Qualification: 
Ph.D
t_sindhu@cb.amrita.edu

Dr. Sindhu Thampatty currently serves as an Associate Professor at the Department of Electrical and Electronics Engineering, School of Engineering, Amrita Vishwa Vidyapeetham, Coimbatore. She joined Amrita in the year 1996 as faculty in the Department of Electrical and Electronics Engineering and was undertaking teaching and projects for B. Tech. and M. Tech. students. She did her B. Tech. in Electrical & Electronics Engineering and M. Tech. in Energetics from NIT Calicut formerly known as Regional Engineering College, Calicut. Her M. Tech. thesis was on Environmentally Constrained Optimum Economic Dispatch.

Dr. Sindhu did her Ph. D. in Power Systems from the National Institute of Technology, Calicut in 2011. Her dissertation was on "A TCSC Based Adaptive SSR Damping Controller Using Real-Time Recurrent Learning Algorithm". She has guided several B. Tech. and M. Tech. research projects.

She has served as a reviewer for research papers in IET Generation, Transmission and Distribution and Electric Power Components and Systems, Taylor and Francis since 2010. She has also served as a technical committee member and reviewer for many conferences.

Research Focus: Electrical Power System Dynamics and Stability Analysis, Flexible AC Transmission Systems, Application of AI Techniques in Power Systems, Stability Issues in Connecting Renewable Sources to Grid, Application of Advanced Controls in Power Systems

In complex electrical power systems consisting of several generators, transmission lines, and loads, the long distance between generating stations and load centers frequently leads to line congestions and overloading. In interconnected power system networks, stability problems are common, and this will increase the complexity of network operation in transmission grids. Currently, I am interested in exploring techniques for the enhancement of power system stability using FACTS technology. Efficient control strategies employed in Flexible AC Transmission system (FACTS) devices can be utilized for the efficient operation and control of power systems. My Doctoral thesis was based on the application of Artificial Intelligence (AI) Techniques in power systems. An adaptive Sub-synchronous Damping Controller (SSDC) based on Recurrent Neural Network (RNN) was developed to control the firing angle of the TCSC. The design of the proposed neuro-controller is based on the Real Time Recurrent Learning (RTRL) algorithm applied to fully connected RNN.

Projects Guided:

  • Undergraduate: 21 Nos
  • Post Graduate:15 Nos

Projects Guided in the Last Four Years:

Undergraduate:

  1. Economic load dispatch using Soft Computing Techniques
  2. Fractional Order Control of a fractional Order System
  3. Design and Implementation of TCSC Controller for Power Flow Enhancement
  4. Design and implementation of a prototype hybrid power supply system for street lighting in Amrita campus
  5. Design and Implementation of PV system for a constant voltage operation
  6. Design and Implementation of fault location identification and isolation in radial feeders

Postgraduate:

  1. Modelling and Implementation of FACTS Controllers for Power System Oscillations Damping
  2. Design, Implementation and Testing of Micro-controller Controlled Static VAR compensator (SVC)
  3. Damping of Power System Oscillations by Series Connected FACTS Devices
  4. Enhancemet of power System Oscillation Damping by coordinate Control of Series Connected Facts
  5. Lookup Table Based Control of Thyristor Controlled Phase Angle Regulator for Power Flow Enhancement
  6. Design and Implementation of a TCSC Controller for Power System Stability Enhancement
  7. Design and Implementation of Feedback Linearisation Control for Unified Power Flow Controller
  8. Detailed Mathematical Modelling of Grid connected SCIG Based Windfarm for subsynchronous Resonance Analysis
  9. Design and implementation of Feedback linearisation controller for power flow enhancement
  10. Parameterization of MATLAB Based IGBT Characterisation

Ph.D. Produced: One:

  1. Analysis, Design and Implementation of Subsynchronous Resonance Damping Controller for DFIG Based Wind Energy Conversion System (Name of Scholar: D. Mahalakshmi, Amrita School of Engineering, Bangaluru)

Ongoing Ph.D. Thesis Supervision :

  1. Design and implementation of a Feedback Linearization controller for UPFC to enhance Power Flow in a transmission system
  2. Enhancement of Grid Stability by Co-ordinated Control of Hybrid Energy Storage in Large Solar PV Generation Portfolio.
  3. Generation Prediction, monitoring and Control of Solar power integrated micro grid using AI techniques

Ongoing Ph.D. Thesis: Co-Supervisor

  1. Renewable Energy integrated Smart DC multi micro-grid.
  2. Design of control system using disturbance
  3. FPGA based fractional order PID controller using PSO
  4. Frequency regulation of power system using electric

Doctoral Thesis:

K.C. Sindhu Thampatty: A TCSC Based Adaptive SSR Damping Controller Using Real-Time Recurrent Learning Algorithm. Dept. of Electrical Engineering, NIT Calicut, 2011. (Guide: Dr. M.P.Nandakumar and Dr. Elizabeth P Cheriyan)

Publications

Publication Type: Journal Article

Year of Publication Title

2020

R. Mahalakshmi and Dr. Sindhu Thampatty K.C., “Detailed Modelling and Development of a Laboratory Prototype for the Analysis of Subsynchronous Resonance in DFIG-based wind Farm”, International Transactions on Electrical Energy Systems, 2020.[Abstract]


The interconnection between the grid and nonconventional energy sources has become more essential due to the huge rise in energy demand. In the case of wind energy, the grid integration undergoes lots of stability issues. The long‐distance transmission lines are preferred since the wind farms are positioned far from the grid. However, this lowers the bulk power transfer ability of the line. The simple solution to enhance the power transfer capacity is the insertion of series capacitor in the line. However, the frightening factor in inserting the series capacitor is subsynchronous resonance (SSR) oscillations which can lead to shaft fatigue between turbine and generator set. This paper focuses on the analysis of SSR in series‐compensated doubly fed induction generator (DFIG)–based wind energy conversion systems (WECSs). The detailed mathematical modelling of DFIG‐based wind turbine generator (WTG) in state space form which is essential for SSR analysis is explained. The proposed model is found to be more accurate as it includes the dynamics of the rotor‐side converter (RSC) and grid‐side converter (GSC). The influence of series capacitive compensation in a WECs is dealt by employing eigenvalue approach. The developed model is embedded with RSC and GSC controllers for analyzing SSR effect for different operating conditions such as wind speed variations and varying compensation levels using MATLAB/SIMULINK. Also, the scaled‐down model of a 2‐MW wind turbine is deployed in laboratory using a grid‐integrated, series‐compensated 1.1‐kW DFIG machine to realize the influence of series capacitive compensation. It is found that the stability of SSR is affected by different wind velocities and capacitive compensation levels.

More »»

2020

R. Mahalakshmi and Dr. Sindhu Thampatty K.C., “Design and implementation of modified RSC controller for the extenuation of sub-synchronous resonance oscillations in series compensated DFIG-based WECS”, International Transactions on Electrical Energy Systems, 2020.[Abstract]


The doubly fed induction generator (DFIG)‐based windfarm is located far away from load points. Hence, the elongated transmission lines are required to transmit the generated power. The high inductive nature of the lengthier transmission line will lessen the transmission power capacity and a very simple solution is to insert the series capacitors along the lines. But this can cause an adverse effect known as sub‐synchronous resonance (SSR) oscillations in the system causing electrical instability and shaft failure. The main motive of this paper is to examine the risk of SSR effect and its damping on series compensated 2 MW DFIG‐based Wind Energy Conversion Systems. The detailed time domain analysis of SSR is carried out using the state space model of the total scheme in MATLAB/SIMULINK and the effective SSR damping control scheme is proposed. Conventionally, an additional sub‐synchronous resonance damping controller is inserted exclusively for damping of SSR oscillations along with the DFIG's own proportional integral (PI)‐based rotor side converter (RSC)‐grid side converter (GSC) controllers. The RSC‐GSC controllers are essential for the control of active‐reactive power and grid synchronization. Insertion of an additional controller in the system leads to controller interactions. In order to avoid the use of an additional SSR damping controller, an efficient fuzzy logic controller (FLC)‐based single controller is developed for RSC. This controller is an effective dual‐purpose controller and is utilized for power control as well as for damping the torque oscillations due to SSR. This work focuses on the design of fuzzy‐based effective controller by modifying DFIG's own converter controllers for the damping SSR oscillations together with its own control responsibilities. Under fast dynamic operating conditions, the conventional PI controllers of the converters are found to be ineffective as they require retuning for the better damping. This proposed fuzzy‐based RSC controller replaces the existing conventional PI‐based RSC controllers. The results are discussed for various wind speeds, compensation levels, etc. The prototype model of series compensated 1.5HP DFIG grid integrated system is developed. The effect of the RSC controller into the series compensated grid connected DFIG is analysed along with the experimental results.

More »»

2019

Dr. Sindhu Thampatty K.C. and T, V., “Model Reference Adaptive Control for DC Servo Motor Positioning System”, International Journal of Industrial Electronics and Electrical Engineering, vol. 7, no. 3, 2019.

2019

Dr. Sindhu Thampatty K.C., Rajiv, A., and Nathan, V., “Detection and Analysis of Rotor Bearing Fault in a Three Phase Induction Motor using MCSA and ANSYS® Maxwell 2D”, i-manager’s Journal on Electrical Engineering, vol. 3, 2019.[Abstract]


Being an integral part of any engineering system, electrical machines are used in all industries. Among all these machines, very common type of machine is induction motors. Motor faults can lead to untimely shutdown of machines and consequently lead to loss of productivity. This can be avoided by the proper detection of fault in the incipient stage itself, which requires a detailed analysis of the fault and clearly understand its effect on the motor. This paper presents a method to analyse the frequently occurring rotor bearing fault on an induction motor. The fault analysis is conducted using two ® parameters: Stator current and voltage by Motor Current Signature Analysis and the motor flux distribution using ANSYS Maxwell 2D.

More »»

2018

Dr. Sindhu Thampatty K.C., S, P., and .N.P.Nambiar, T., “Design of Feedback Linearization Controller for STATCOM for VAR compensation in an Interconnected System”, International Journal of Power and Energy Systems, ACTA Press, 2018.[Abstract]


The bulk power transmission is an interconnected system which gives more attention to the use of flexible AC transmission systems (FACTS). The transmission lines are loaded with a substantial amount of active and reactive power, so the voltage stability is inferior on the load buses. Static compensator (STATCOM) is a shunt connected FACTS device and is extensively used as a remedial measure for voltage instability issues in the power system. The nonlinear behaviour of power systems and switching converters in the STATCOM degrades the performance under dynamic conditions. This paper focussed on a nonlinear MIMO state-space model of STATCOM controlled by a nonlinear feedback linearization controller (FBLC). This paper investigates the effectiveness of two popular approaches of FBLC in a nonlinear system, which are input–output feedback linearization controller (IOFL) and partial feedback linearization controller (PFBLC). A detailed simulation analysis is performed under different operating conditions, and it is validated in the standard IEEE 5 bus system. The in-depth result analysis shows the superiority of PFBLC over the IOFL and PI controller. Furthermore, the PFBLC controller can widen the operating range of STATCOM, fast convergence of the parameters to set values and make absolute decoupling control of the parameters. All performance analyses and simulation studies prove the admirable performance of PFBLC in power system applications.

More »»

2018

M. Rajaram, Deepa, K., and Dr. Sindhu Thampatty K.C., “Analysis of Multi Level Current Source Inverter for Low Torque Applications”, Journal of Green Engineering, vol. 8, pp. 597-620, 2018.[Abstract]


This paper proposes a control strategy for a multi-level Current Source Inverter (CSI) which acts as an interface between renewable energy sources such as wind, solar, fuel cell etc. and grid/loads to satisfy the power demand. The control strategy aims to reduce the number of switches and the number of input sources used in the CSI and obtain an output with least Total Harmonic Distortion (THD) and increased number of levels (13). The proposed system uses seven switches and three current sources to obtain a 13 level output. The new control strategy is tested in different operating conditions in a split phase single phase low torque induction motor. The Simulation model is developed in MATLAB/Simulink. THDs of 13 level outputs from current source inverter is analyzed and compared in detail. A comparative analysis of the proposed CSI with existing CSI topologies is made. It is observed that the proposed topology uses less number of switches and inductors to obtain different levels at the output. The proposed inverter provides better performance with satisfactory results

More »»

2018

S. Reddy Ginugu, SekharKammala, R., Baburajan, H., and Dr. Sindhu Thampatty K.C., “Parameterization of MATLAB based IGBT and results validation”, Journal of Advanced Research in Dynamical and Control Systems, vol. 3-Special Issue, no. Special issue, pp. 965-969, 2018.[Abstract]


Simulation tools are playing prominent roles in the engineering design applications. By using the simulation tool IGBT parameters can be tuned and that can be used in the modelling of inverter. A good IGBT model will help us in calculating the Electric Drive (which consist of battery, inverter, and electric machine along with control) dynamics with better accuracy. To evaluate efficiency of inverter, IGBTs need to be validated as per datasheet specifications. In this study, initially IGBT�s used for modelling are validated, tested in simulation environment and further used for investigation. With math works provided IGBT in fixing the parameters as per data sheet, some parameters which needs to be filled additionally in IGBT block are taken as default for every data sheet which does not provide good response. So, for finding the unknown parameters certain standardized procedure should be followed. Simulink optimization design tool is used for parameterizing the IGBT specifications taken from the data sheet. A standard IGBT test circuit model is developed in Simulink and tested for IGBT characteristics from data sheet. In this paper by using Simulink design optimization tool the results are validated between the simulated characteristics w.r.t the data sheet characteristics.

More »»

2018

R. Mahalakshm, .Deepa, K., and Dr. Sindhu Thampatty K.C., “Current Source Multi Level Inverter for Renewable Energy Integration”, Journal of Green Engineering, 2018.

2016

G. A.S and Dr. Sindhu Thampatty K.C., “Design And Implementation Of Series Connected FACTS Devices For Enhancing Powersystem Oscillation Damping”, International Journal of Advanced Information in Engineering Technology (IJAIET), vol. 3, 2016.[Abstract]


This paper presents a way to increase power transfer capability of the system and improve power oscillation damping by series connected two FACTS devices, Thyristor Controlled Series Capacitor (TCSC) and a Thyristor Controlled Phase Angle Regulator (TCPAR). This paper also describes a practical implementation and analysis of proposed system in laboratory.

More »»

2016

P. Anusri and Dr. Sindhu Thampatty K.C., “Mathematical modeling of the squirrel cage induction generator based wind farm for sub-synchronous resonance analysis”, Indian Journal of Science and Technology, vol. 9, 2016.[Abstract]


Background/Objectives: To analyze the SSR phenomenon in a Squirrel Cage Induction Generator based Wind farm connected to series compensated transmission line at varying operating conditions. Methods/Statistical Analysis: There is a remarkable rise in the renewable energy sector in the current energy demand scenario, but their grid integration leads to various power system stability issues. In the case of wind power, wind farms being located far away from the grid, the integration of large scale wind farms to the utility grid requires high transmission line capacity to transport huge amount of wind power. In order to provide the power transfer capability and to improve the system stability, series compensation is the effective solution. But the series compensation may cause SSR oscillations in the system. Eigen value analysis is the method chosen to perform the Small Signal Stability analysis which examines the potential of SSR in the study system. Findings: The study investigates on the application of series capacitor for series compensation which is required during the grid integration. Series compensation of transmission line causes electro-mechanical oscillations at a sub-synchronous frequency which may finally result in serious damages in the system such as shaft failure. In order to perform the Eigen value analysis, detailed mathematical modeling of the system is developed. The pitch angle control is not taken into account while developing the system, whereas the strength of the transmission line is considered. The interconnection of three sub systems provides the complete model of the study system. The identification of system modes and damping of torsional and network modes are analyzed for various wind speed levels, various series compensation levels and various grid impedance levels. It has been observed that different grid impedance levels have a significant effect on the torsional mode oscillations of the system. Application/Improvements: As the overall system model is linearised, optimal control techniques can be developed as an application to mitigate the SSR oscillations and thereby improve the system stability.

More »»

2015

Dr. Sindhu Thampatty K.C., .T, H., and .S, P., “Look-up Table Based Control of Thyristor Controlled Phase Angle Regulator for Power Flow Enhancement”, International Journal of Applied Engineering Research, vol. 10, pp. 3596 - 3601, 2015.[Abstract]


This paper focuses on the improvement of power flow in a transmission line by using a Flexible Alternating Current Transmission System (FACTS) device i.e., Thyristor Controlled Phase Angle Regulator (TCPAR) in series with the transmission line. Furthermore, the look-up table based control of the same system is also discussed. The simulation, practical implementation and the analysis of results of the proposed system is described in this paper.

More »»

2015

Dr. Sindhu Thampatty K.C. and Raj, P. C. Reghu, “An Adaptive RTRL Based Neurocontroller for Damping Power System Oscillations”, International Journal of Applied Power Engineering (IJAPE) , vol. 4, no. 1, pp. 1-12, 2015.[Abstract]


The main objective of this paper is to present the design of an adaptive neuro-controller for series connected FACTS devices like Thyristor Controlled Series Capacitor (TCSC) and Thyristor controlled Power Angle Regulator (TCPAR). This control scheme is suitable for non-linear system control, in which the exact linearised mathematical model of the system is not required. The proposed controller design is based on Real Time Recurrent Learning (RTRL) algorithm in which the Neural Network (NN) is trained in real time. This control scheme requires two sets of neural networks. The first set is a neuro-identifier and the second set is a neurocontroller which generates the required control signals for the thyristors. Performance of the system is analysed with the proposed controller using standard simulation environments like MATLAB/SIMULINK and it has been observed that the controlleris robust and the response is very fast. Performance of the system with proposed controller is compared with conventional PI controllers and GA based PI controllers. Performace of the proposed controller is extremely good.

More »»

2015

R. .Mahalakshmi and Dr. Sindhu Thampatty K.C., “Grid Connected Three Phase Six Level Inverter for Renewable Energy Applications”, Elsevier, Procedia Technology , vol. 21, pp. 581-588, 2015.[Abstract]


Electrical energy generation from renewable energy sources such as sun, wind etc., are widely adopted due to the increase in electricity consumption. The integration of renewable energy sources with the grid plays an important role in energy utilization. It is difficult to utilize electricity from renewable energy sources directly for the injection of power into the grid. Hence the system needs power electronic converters as an interface between renewable energy sources and grid/load. This paper discusses about the integration of three phase six level voltage source inverter into the grid. Three phase 2000 VA inverter is designed by using three, single phase eight switch six level inverters (in quarter cycle) and each single phase inverter uses three DC voltage sources which can be derived from renewable energy sources such as solar, wind and fuel cell. The pure sinusoidal 415 V three phase voltage is obtained from inverter to inject the power into grid and to the three phase resistive load. The proposed three phase Multi Level Inverter (MLI) is compared with the conventional three phase inverter and the observed THD of the conventional MLI is 31%. THD of the proposed MLI output voltage is analyzed which is 0.13% and found to be very less compared to six and 12 pulse conventional converter topologies. The simulation on the proposed inverter topology is done in MATLAB/Simulink and the results are verified.

More »»

2015

P. S and Dr. Sindhu Thampatty K.C., “Dynamic Modeling and Control of UPFC for Power Flow Control”, Elsevier, Procedia Technology , vol. 21, pp. 581-588, 2015.[Abstract]


Unified Power Flow Controller can control the power system parameters like voltage, line reactance and phase angle to control power flow in the transmission line. The control of power flow in the transmission line done by injecting a suitable voltage with a phase angle. In this paper design a decoupled control scheme for shunt and series converter to track the reference power inputs by using conventional PI controller. Modeling is done by using MATLAB/SIMULINK software. The analysis is done on the system with different power factors and load conditions. The results show that UPFC is able to track the power changes and inject a suitable voltage into the power system so that power flow can be maintai

More »»

2015

R. Mahalakshmi and Dr. Sindhu Thampatty K.C., “Implementation of Grid Connected PV array using Quadratic DC-DC Converter and Single Phase Multi Level Inverter”, Indian Journal of Science and Technology, vol. 8, no. 35, 2015.[Abstract]


Electrical energy generation from solar and wind is increasing day by day and the extraction of good quality electrical energy effectively as well as efficiently is really challenging. This paper focuses on the extraction of electrical energy from solar cells and interconnecting it to the single phase grid through a Quadratic Buck-Boost Converter (QBBC) and Multi Level Inverter (MLI). MLI uses three DC sources, one of which is derived from the solar array through QBBC with Maximum Power Point Tracking (MPPT) controller. In this paper, a new converter topology which accepts wide variations in input voltage has been designed to produce minimum distortion in MLI output with reduced number of switches. The proposed system is designed and implemented in the laboratory and the output is analyzed in different operating conditions

More »»

2015

R. Mahalakshmi and Dr. Sindhu Thampatty K.C., “ Grid Connected Multilevel Inverter for Renewable Energy Applications”, Procedia Technology, vol. 21, pp. 636 - 642, 2015.[Abstract]


Electrical energy generation from renewable energy sources such as sun, wind etc., are widely adopted due to the increase in electricity consumption. The integration of renewable energy sources with the grid plays an important role in energy utilization. It is difficult to utilize electricity from renewable energy sources directly for the injection of power into the grid. Hence the system needs power electronic converters as an interface between renewable energy sources and grid/load. This paper discusses about the integration of three phase six level voltage source inverter into the grid. Three phase 2000 VA inverter is designed by using three, single phase eight switch six level inverters (in quarter cycle) and each single phase inverter uses three DC voltage sources which can be derived from renewable energy sources such as solar, wind and fuel cell. The pure sinusoidal 415V three phase voltage is obtained from inverter to inject the power into grid and to the three phase resistive load. The proposed three phase Multi Level Inverter (MLI) is compared with the conventional three phase inverter and the observed THD of the conventional MLI is 31%. THD of the proposed MLI output voltage is analyzed which is 0.13% and found to be very less compared to six and 12 pulse conventional converter topologies. The simulation on the proposed inverter topology is done in MATLAB/Simulink and the results are verified. More »»

2015

Aa Rajiv, Nathan, Va, Ashwanth, Aa, Rajan, Sa, and Dr. Sindhu Thampatty K.C., “Modelling and analysis of rotor bearing fault in a three phase squirrel cage induction motor using ANSYS® Maxwell 2D”, International Journal of Applied Engineering Research, vol. 10, pp. 3612-3616, 2015.[Abstract]


Industries of all kinds use electrical machines and they also form the integral part of any engineering system. Induction motors are widely used in industrial and domestic applications. There are various faults that occur in an induction motor, like stator inter-turn fault, bearing fault and eccentricity fault. Out of these faults, the rotor bearing fault is very specific in squirrel cage induction machines. This paper presents the design and modelling of a three phase squirrel cage induction motor using the CAD package called “ANSYS® Maxwell 2D” and its analysis under two states of operation: healthy mode of operation and motor operation under the presence of a bearing fault. © Research India Publications.

More »»

2015

R. Mahalakshmi, Manjunath, H. V., and Dr. Sindhu Thampatty K.C., “Design and Implementation of Quadratic Buck-Boost Converter for PV Array”, International Journal of Applied Engineering Research, vol. 10, pp. 1023-1034, 2015.[Abstract]


<p>Due to increase in electric energy demand, energy extraction from solar and wind are much concentrated in power electronic systems. There is a wide variation in the output of solar array and it needs efficient DC-DC converter. This paper discusses about the design and implementation of closed loop control of Quadratic buck boost converter for the variable DC input voltage whose voltage ratio is -D2/(1-D)2.This converter uses a single switch to control output voltage unlike cascaded buck and buck boost converters. Cascaded conventional converter uses two switches for the same voltage ratio of -D2/(1-D)2. They also suffer from duty cycle and switching frequency limitations during wide input voltage variations. These problems can be reduced with the help of quadratic converter. In this paper quadratic closed loop control of buck boost converter is proposed for the variable solar panel output. Simulation of the circuit is done using MATLAB simulink and hardware implementation results are discussed. © Research India Publications.</p>

More »»

2014

M. S., Dr. Sindhu Thampatty K.C., and N., A., “Design and implementation of a look up table based TCSC controller for power system stability enhancement”, International Journal of Applied Engineering Research, vol. 10, no. 55, pp. 2741-2747, 2014.[Abstract]


The demand for electric power is increasing day by day and it is difficult to build new power lines while considering environmental and economical aspects. While increasing the loading of routing lines it may result in the poor damping of power system oscillations. This paper presents the design and hardware implementation of GA based TCSC controller for power system stability enhancement. The effective control is brought by the help of most robust artificial intelligence technique, i.e. Genetic Algorithm. The hardware implementation of this work is completed with the lookup table based control achieved from Arduino. MATLAB/SIMULINK is used to examine the transient stability of the system while incorporating TCSC to the Single machine infinite bus system. Performance analysis of the hardware set up obtained shows that this approach is far better and economical than any other alternatives.

More »»

2013

Dr. Sindhu Thampatty K.C. and Raj, P. C. Reghu, “A Robust Dlqg Controller for Damping of Sub-synchronous Oscillations in a Series Compensated Power System”, International Journal of Research in Engineering and Technology, vol. 02, no. 4, pp. 724-740, 2013.[Abstract]


This paper investigates the use of Discrete Linear Quadratic Gaussian (DLQG) Compensator to damp sub synchronous oscillations in a Thyrisor Controlled Series Capacitor (TCSC) compensated power system. The study is conducted on IEEE First Benchmark Model (FBM) in which, TCSC is modelled as a discrete linear time-invariant modular unit in the synchronously rotating DQ reference frame. This modular TCSC is then integrated with the Linear Time Invariant (LTI) model of the rest of the system. The design of DLQG includes the design of a Kalman filter for full state estimation and a full state feedback for control. Since the order of the controller is as large as the order of the system considered here(27 states), the practical implementation of the controller is difficult. Hence by using Hankels norm approximation technique, the order of the controller is reduced from 27 to 15 without losing the significant system dynamics. The eigen analysis of the system shows that the use of DLQG can damp torsional oscillations as well as the swing mode oscillations simultaneously, which is practically difficult for a conventional sub-synchronous damping controller. The performance of the system with DLQG is appreciable for all operating conditions and it shows the robustness of the controller.

More »»

2011

Dr. Sindhu Thampatty K.C., .P.Nandakumar, M., and P.Cheriyan, E., “Adaptive RTRL based neurocontroller for damping subsynchronous oscillations using TCSC”, Engineering Applications of Artificial Intelligence, vol. 24, no. 1, pp. 60-76, 2011.[Abstract]


Modern interconnected electrical power systems are complex and require perfect planning, design and operation. Hence the recent trends towards restructuring and deregulation of electric power supply has put great emphasis on the system operation and control. Flexible AC transmission system (FACTS) devices such as thyristor controlled series capacitor (TCSC) are capable of controlling power flow, improving transient stability and mitigating subsynchronous resonance (SSR). In this paper an adaptive neurocontroller is designed for controlling the firing angle of TCSC to damp subsynchronous oscillations. This control scheme is suitable for non-linear system control, where the exact linearised mathematical model of the system is not required. The proposed controller design is based on real time recurrent learning (RTRL) algorithm in which the neural network (NN) is trained in real time. This control scheme requires two sets of neural networks. The first set is a recurrent neural network (RNN) which is a fully connected dynamic neural network with all the system outputs fed back to the input through a delay. This neural network acts as a neuroidentifier to provide a dynamic model of the system to evaluate and update the weights connected to the neurons. The second set of neural network is the neurocontroller which is used to generate the required control signals to the thyristors in TCSC. This is a single layer neural network. Performance of the system with proposed neurocontroller is compared with two linearised controllers, a conventional controller and with a discrete linear quadratic Gaussian (DLQG) compensator which is an optimal controller. The linear controllers are designed based on a linearised model of the IEEE first benchmark system for SSR studies in which a modular high bandwidth (six-samples per cycle) linear time-invariant discrete model of TCSC is interfaced with the rest of the system. In the proposed controller, since the response time is highly dependent on the number of states of the system, it is often desirable to approximate the system by its reduced model. By using standard Hankels norm approximation technique, the system order is reduced from 27 to 11th order by retaining the dominant dynamic characteristics of the system. To validate the proposed controller, computer simulation using MATLAB is performed and the simulation studies show that this controller can provide simultaneous damping of swing mode as well as torsional mode oscillations, which is difficult with a conventional controller. Moreover the fast response of the system can be used for real-time applications. The performance of the controller is tested for different operating conditions.

More »»

2010

Dr. Sindhu Thampatty K.C., Nandakumar, M. P., and Cheriyan, E. P., “RTRL Algorithm Based Adaptive Controller for Non-linear Multivariable Systems”, International Journal of Computer Applications, vol. 1, 2010.[Abstract]


The paper presents a new design of adaptive and dynamic neural network-based controller architecture with feedback connection for non-linear multivariable systems. The network is trained on-line at each sampling interval using the desired output trajectory and the training method used is the Real Time Recurrent Learning Algorithm (RTRL). The recurrent network is a fully connected one, with feedback from output layer to the input layer through a delay element. Since the synaptic weights to the neurons are adjusted on-line, this controller has potential applications in real time control also. Moreover, it can be used for both continuous and discrete systems. The simulation results obtained by applying the algorithm to a non-linear multivariable system demonstrate the effectiveness of the proposed method.

More »»

2009

Dr. Sindhu Thampatty K.C., Nandakumar, M. P., and Cheriyan, E. P., “RTRL based Multivariable Neurocontroller for Non-linear Systems”, ISAST Transactions on Computers and Intelligent Systems, vol. 1, no. 2, pp. 67-74, 2009.

2009

Dr. Sindhu Thampatty K.C., Nandakumar, M. P., and Cheriyan, E. P., “A Non-linear Multivariable System Controller Based on Real-Time Recurrent Learning Algorithm”, ISAST Transactions on Electronics and Signal Processing, vol. 4, no. 1, pp. 129-136, 2009.

2008

Dr. Sindhu Thampatty K.C., Cheriyan, E. P., and Nandakumar, M. P., “Sub-synchronous Resonance Phenomenon in Series Compensated Power Systems”, Proc. of National Conference CISCON 2008, 2008.

Publication Type: Conference Paper

Year of Publication Title

2019

Dr. Sindhu Thampatty K.C., “Design of MRAC based TCSC for Damping Sub-Synchronous Oscillations in SCIG Based Wind farm”, in TENCON 2019 - 2019 IEEE Region 10 Conference (TENCON), 2019.

2018

S. S. and Dr. Sindhu Thampatty K.C., “A study on MRAC, LQR and MPC controllers for a Vertical Take-off and Landing System”, in 2018 International Conference on Circuits and Systems in Digital Enterprise Technology (ICCSDET), 2018.[Abstract]


This paper presents the study and analysis of linear, adaptive and predictive controllers for pitch control of Vertical Take-off and Landing System (VTOL). Since VTOL aircraft system is a highly nonlinear system with varying aerodynamic parameters. Adaptive controllers are capable of achieving good performance in the presence of significant parametric uncertainties without the exact knowledge of the plant model. Fixed gain Linear Quadratic Regulator (LQR) controllers are optimal in nature and constrained optimization problems can be easily solved by Model Predictive Controller (MPC). This paper mainly focuses on the modeling of VTOL system and performance analysis of the system with linear, adaptive and predictive controllers.

More »»

2018

P. S, PadmanabhanNambiar, T. N., and Dr. Sindhu Thampatty K.C., “Modelling and Non linear Control of SSSC to enhance Power Flow in IEEE 5 bus system”, in IEEE Power Electronics, Drives and Energy Systems Conference PEDES2018, Indian Institute of Technology Madras in Chennai, Tamilnadu., 2018.

2018

S. S and Dr. Sindhu Thampatty K.C., “A study on MRAC, LQR and MPC controllers for a Vertical Take-o_ and Landing System”, in IEEE International Conference on Circuits and Systems in Digital Enterprise Technology, IEEE ICCSDET 2018, 2018.

2018

P. S, Dr. Sindhu Thampatty K.C., and PadmanabhanNambiar, T. N., “Input- Output Linearization Control of SSSC for Power Flow Enhancement in a Power System Network”, in 2018 15th IEEE India Council International Conference (INDICON).IEEE INDICON 2018 , Amrita VishwaVidyapeetham, Coimbatore, 2018.

2018

P. V. Sunil Nag, Kumar, C. S., Dr. Sindhu Thampatty K.C., and Isha, T. B., “A Modified Approach for Application of Augmented Extended Kalman filter for Stator Interturn fault Diagnosis of a Synchronous Generator”, in Proceedings of the 4th International Conference on Electrical Energy Systems, ICEES 2018, 2018, pp. 465-469.[Abstract]


Stator interturn fault diagnosis of electrical machines has been a very intensely researched area. The synchronous generator (SG) is a very important component of a power system and there are only a few works that deal with the model based approach to fault diagnosis of a wound rotor synchronous generator. This work deals with the application of augmented Extended Kalman Filter (EKF) to obtain the residual signal for an SG. This signal contains the signature of the fault and can distinguish an interturn fault from a load imbalance of similar magnitude.

More »»

2018

K. P. P. Cauvery, Dharanidhar, P., and Dr. Sindhu Thampatty K.C., “Design and implementation of a prototypic hybrid power supply system for street lighting”, in 5th IEEE Region 10 Humanitarian Technology Conference 2017, R10-HTC 2017, 2018, vol. 2018-January, pp. 831-836.[Abstract]


The energy consumption in lighting is increasing day by day. Lot of efforts have been made in order to minimize the energy consumption in lighting. As a part of it, new energy efficient lights, improved lighting design and advanced lighting controls are evolved. Photovoltaic (PV) is the best solution for the energy requirements in the future. This paper proposes a method to maximize the utilization of available solar energy for the efficient street lighting design. This paper presents the design and implementation of a grid-solar hybrid power supply scheme for LED street lighting. The existing street lighting scheme in a part of the University is studied, simulated on DIALux, a lighting analysis software and the problems are analyzed in detail. In order to overcome the problems, a more efficient lighting scheme is proposed. A prototype scaled down model of the proposed lighting scheme is designed and implemented. This scheme utilizes the solar energy in a more efficient way. A control strategy is developed for switching the lamps between solar and grid supply. The control principles and illumination design of the hardware and software are presented. © 2017 IEEE.

More »»

2017

S. Parvathy, Dr. Sindhu Thampatty K.C., and Nambiar, T. N. P. P., “Analysis and modeling of UPFC: A comparison between power injection model and voltage source model”, in 2017 IEEE Region 10 Symposium (TENSYMP), Cochin, India, 2017.[Abstract]


The interconnected systems are equipped with Flexible AC transmission Systems (FACTS) for better control on power transfer capability and stability improvement. The operation of these devices can be explained with different modeling techniques. Unified Power Flow Controller (UPFC) is one of the FACTS device with multivariable control capability. Different load flow models have been investigated to study the impact of UPFC in load flow solution. Power injection model and voltage source based model of UPFC are used for study the effect of UPFC in an interconnected system. So this paper focuses on the performance analysis and comparison of these UPFC models in a standard IEEE 5 bus system.

More »»

2017

A. Parol and Dr. Sindhu Thampatty K.C., “Design of Linear Quadratic Regulator (LQR) controller for the Mathematically Modeled Squirrel Cage Induction Generator based Wind farm for Sub-synchronous Resonance (SSR) Analysis”, in IEEE TENSYMP 2017 Technologies for Smart Cities, Le- Meridian, Cochin , 2017.

2017

Dr. Sindhu Thampatty K.C. and Raj, P. C. R., “RTRL based adaptive neuro-controller for damping SSR oscillations in SCIG based windfarms”, in TENCON 2017 - 2017 IEEE Region 10 Conference, Penang, Malaysia, 2017.[Abstract]


As the global energy consumption is rising dramatically, wind energy is a prominent one among the renewable energy sources. The penetration of wind energy into grid is increasing day by day. In order to carry huge amount of wind power during the grid integration of large scale wind farms, high transmission line capability is demanded. In order to improve the power carrying capability of the transmission line and to improve the stability of the system, series compensation is the best practical solution. Series compensation can result in Sub-Synchronous Resonance (SSR) oscillations in the electrical system which will lead to damages in the system such as shaft failure. In this paper, a novel idea of using the Real Time Recurrent Learning (RTRL) based adaptive neuro controller is proposed for damping SSR oscillations in grid connected windfarms. The controller is trained in real time without a reference model. The effectiveness of the proposed controller is tested under varying series compensation, wind speeds and grid impedance conditions and it has been proved that the proposed controller performs far better than any other linear controllers.

More »»

2017

R. Mahalakshmi and Dr. Sindhu Thampatty K.C., “A fuzzy based adaptive controller for grid connected DFIG based windfarm for damping SSR oscillations”, in TENCON 2017 - 2017 IEEE Region 10 Conference, Penang, Malaysia, 2017.[Abstract]


Grid integrated wind energy conversion system is highly known among all renewable energy sources. Grid integrated wind farm undergoes many technical challenges. Wind farms need long transmission line for the grid integration. As long transmission line exhibits high inductive reactance, capacitive series compensation is required to improve the transmission capacity. Insertion of capacitive compensation in a line causes Sub Synchronous Resonance (SSR) Oscillations in the system. These oscillations may lead to a permanent damage in the turbine-shaft system. This paper proposes a novel fuzzy based adaptive controller for Rotor Side Converter (RSC) and Grid Side Converter (GSC) for damping SSR oscillations in a grid connected DFIG based wind farm. The paper describes the development of a mathematical model of the proposed system in detail and small signal stability for SSR oscillations is analyzed using Eigen value approach. Oscillation. Performance of the proposed controller is tested under varying operating conditions and it has been observed that the fuzzy based controller adopts the changes in the system operating conditions and gives satisfactory performance compared with conventional PI controller.

More »»

2017

S. Parvathy, Dr. Sindhu Thampatty K.C., and NAMBIAR, T. N. P., “Modeling and non linear control of STATCOM for VAR compensation in IEEE 5 bus system”, in 2017 IEEE PES Asia-Pacific Power and Energy Engineering Conference (APPEEC), Bangalore, India, 2017.[Abstract]


The power transmission network and its effective utilization are the recent topic of interest. Flexible AC Transmission Systems (FACTS) devices are equipped in the transmission lines for control of real and reactive power flow. The reactive power compensation can be done with STATic COMpensator (STATCOM). The appropriate amount of reactive power generated by the STATCOM will improve voltage stability in the buses. The Non Linear Controller namely Feedback Linearization Controller (FBLC) is used for controlling the Voltage Source Converter of STATCOM. The closed loop control of STATCOM with FBLC using MATLAB/SIMULINK is described in this paper. The results shows that with the proposed controller, DC link capacitor voltage and AC coupling voltage of STATCOM are attained its desired value. The load flow analysis with STATCOM in IEEE 5 bus system shows that losses in the network are reduced and thus transmission efficiency is improved.

More »»

2017

V. Balacoumarane, Karthik, B., Pranav, K. V. S., Sandeep, S. A., and Dr. Sindhu Thampatty K.C., “Design and implementation of PV system for a constant voltage operation”, in 2017 International Conference On Smart Technologies For Smart Nation (SmartTechCon), Bangalore, India, 2017.[Abstract]


Renewable energy source based distributed power generation systems are gaining popularity because of fast depletion of conventional sources of energy and also the environmental threats they are causing. Interfacing of renewable energy sources with the utility grid is achieved using power electronic converters. Among all the Renewable sources, solar power is the most effective because of the advances in the Photovoltaic industry. Since the solar power is mainly depending on environmental conditions, the large-scale integration of solar PV has a large impact on the system stability issues. In this paper scheme for stabilising the voltage at a constant level in PV connected system. Photovoltaic system to the gird for constant voltage operation is explained. The solar PV system consists of two-stages of conversion. The two stages are, boost converter and inverter. In first stage, controller is built across the boost converter which ensures a constant voltage to the DC-link capacitor. The algorithm is implemented using PIC16F877A microcontroller. Controller reads both input and DC-link voltages to minimise the error so as to maintain a constant output voltage. The second stage involves an inverter which is capable of providing a constant voltage across the load due to the constant DC-link voltage. An IRAM 136-1061a inverter is used and the gating pulses for the inverter is generated using PWM switching operation. The full system including the boost converter, the controller and inverter is tested various irradiances conditions and it has been observed that the system is able to provide constant voltage across the inverter output terminals for all these conditions. In this paper, a system to the integration of the Photovoltaic system to the grid is designed and implemented for a constant voltage operation.

More »»

2017

S. Parvathy, Dr. Sindhu Thampatty K.C., and NAMBIAR, T. N. P., “Response of voltage source model of UPFC in an IEEE 5 bus system for power flow enhancement”, in 2017 International Conference on Technological Advancements in Power and Energy ( TAP Energy), Kollam, India, 2017.[Abstract]


The power system is overwhelmed with the load demand during peak hours. The Flexible AC Transmission Systems (FACTS) have better control on the power flow in an interconnected system. Unified Power Flow Controller (UPFC) is a FACTS device can improve the control of power flow in a transmission system. The IEEE 5 bus network is a benchmark system taken in this paper in order to check the response of UPFC on the power flow enhancement. UPFC is modeled in different ways to analyze power flow and voltage improvement at each bus. In this paper UPFC is modeled as a Voltage Source Model (VSM) and that will generate reference bus voltage and phase angle at different load conditions on the receiving end of UPFC. The variation between the voltage generated by VSM and actual voltage profile in the bus is injected in the line through an injection transformer. The entire system simulation shows that voltage stability of the system is getting improved and power flow through the system with UPFC is enhanced.

More »»

2017

K. K. Kumari and Dr. Sindhu Thampatty K.C., “Analysis of magnetic fields due to transformer coils in plasma formation and fusion applications”, in 2017 International Conference on Technological Advancements in Power and Energy ( TAP Energy), Kollam, India, 2017.[Abstract]


The magnetic null is of greatest significance for plasma formation in any Fusion Reactor device. In Ideal case, the radial and vertical component of the magnetic field produced by the Ohmic transformer coil should be approximately zero at some specific location inside the vacuum vessel. Non-zero radial &amp; vertical component of the magnetic field within the plasma region acts as error field and causes difficulties in the gas breakdown. The error field effect can be compensated by placing the transformer coils in series with the solenoid coil. These coil positions must be estimated precisely for designed plasma current inception. This paper proposes a method to optimize the coil positions in order to obtain the null position at the described location inside the vacuum vessel. After optimal positioning of the coils, the magnetic field and plasma formation are analyzed using ANSYS, EFFI, and Poisson codes. The analysis is conducted at Plasma Research Lab. The results obtained with ANSYS simulation is validated with Analytical calculations.

More »»

2017

Dr. Sindhu Thampatty K.C. and Parol, A., “Design of linear quadratic regulator for SCIG based wind farm to damp SSR oscillations”, in TENSYMP 2017 - IEEE International Symposium on Technologies for Smart Cities, 2017.[Abstract]


As the penetration of wind energy to the grid is increasing drastically, the transmission line must be capable of handling large power which demands the series capacitor compensation for the lines. This can result in Sub-synchronous oscillations in the system. This paper explains the detailed mathematical modeling of a Squirrel Cage Induction Generator (SCIG) based wind farm, which is interconnected to the grid through a series, compensated transmission line. The detailed Sub-synchronous Resonance (SSR) analysis has been conducted under various operating conditions such as varying wind penetration levels, varying series compensation levels and varying grid impedance levels. Damping of different modes of SSR oscillations are analysed using the eigen value method. A Linear Quadratic Regulator has been designed for damping of these oscillations. The performance of the system with the proposed controller is analyzed for different operating conditions and the performance was satisfactory. © 2017 IEEE. More »»

2017

N. Geetha, Parvathy, S., and Dr. Sindhu Thampatty K.C., “Output voltage regulation of controlled rectifiers using feedback linearization control algorithm”, in 2017 IEEE International Conference on Signal Processing, Informatics, Communication and Energy Systems, SPICES 2017, Kollam, India, 2017.[Abstract]


PWM converters are usually controlled using linear control techniques. As the linear control techniques have a disadvantage of requiring tuning from time-to-time, non-linear control techniques were employed for the control. One such non-linear control technique is feedback linearization control (FBLC). A control strategy for controlling the output voltage of three phase PWM converters through a linearization technique is discussed in this paper. Feedback linearization technique allows a few advantages like the decoupled control of the state variables, wide operating region. The performance analysis of the converter control using FBLC is done for varied conditions of load. The results from simulation of the controller and the analysis made on the thus linearised system shows the effectiveness of the Feedback linearization technique on different operating conditions. © 2017 IEEE.

More »»

2017

N. Aarthi, Vijayakumari, A., Dr. Sindhu Thampatty K.C., and Nambiar, T. N. P., “Single stage grid connected solar micro-inverter with two level fuzzy logic MPPT controller”, in Proceedings of IEEE International Conference on Circuit, Power and Computing Technologies, ICCPCT 2017, Kollam, India, 2017.[Abstract]


This paper presents a single stage grid connected three phase micro inverter for transfer of power from a solar array to grid controlled by a two level fuzzy logic controller. The system utilizes a line commutated inverter, thus the need for synchronization modules are eliminated. A fuzzy logic controller is designed and developed to track the maximum power from the PV panel and generate an appropriate control variable which is compatible for the switching of thyristorised converter. A two level logic is chosen for faster convergence with variable correction steps for the fuzzy logic controller. The maximum power point voltage window is identified from the PV array characteristics and the rule base for the two levels is developed. The system is tested for two array ratings of 5.8 kW and 8.7 kW to bring out the generic nature of the proposed fuzzy controller for power tracking. The micro inverter system is executed in MATLAB/Simulink for varying ambient conditions of the PV panel and the power balance is verified as proof of theory. © 2017 IEEE.

More »»

2017

Dr. Sindhu Thampatty K.C. and Raj, P. C. R., “Design and Implementation of RTRL Based Adaptive Controller for TCSC to enhance power system stability”, in IEEE Region 10 Annual International Conference, Proceedings/TENCON, Singapore, Singapore, 2017, pp. 812-817.[Abstract]


The power system complexity is increasing day by day and the requirement of stable, secure and high quality electrical power is mandatory in present scenario. Flexible AC Transmission System (FACTS) devices such as Thyristor Controlled Series Capacitor (TCSC) are commonly used nowadays to improve the power system performance. This paper presents the design and Implementation of non-linear, Adaptive Real Time Recurrent Learning Algorithm (RTRL) based controller for TCSC to damp power system oscillations and enhance the stability of the system. This control scheme requires two sets of neural networks. The first set is a neuro-identifier and the second set is a neuro-controller which generate the required control signals for the thyristors. © 2016 IEEE.

More »»

2017

R. Mahalakshmi and Dr. Sindhu Thampatty K.C., “Sub-Synchronous Resonance analysis on DFIG based windfarm”, in IEEE Region 10 Annual International Conference, Proceedings/TENCON, 2017, pp. 930-935.[Abstract]


The rapidly growing level of wind energy injection into the grid is insisting the modifications in power system. In order to improve power transfer capability, series capacitive compensation in the transmission line is adopted which leads to Sub Synchronous Resonance (SSR) oscillations. The main objective of this paper is to develop a dynamic model of Doubly Fed Induction Generator (DFIG) based wind farm connected into grid through series compensated transmission line for SSR studies. The small signal stability studies are carried out through Eigen value approach. State space representation of the whole system is developed. Different modes of the systems are identified for different wind speeds and for various series compensation levels.

More »»

2016

A. M.J., Parvathy, S., and Dr. Sindhu Thampatty K.C., “Feedback Linearization Control Technique for Unified Power Flow Controller”, in Second International Conference on Power, Circuit and Information Technologyies ICPCIT 2016, Rajarajeswari College of Engineering Bangaluru, Karnataka, May 20-21, 2016.

2016

A. M.J, Parvathy, S., and Dr. Sindhu Thampatty K.C., “Feedback Linearization Control Technique for Uni_ed Power Flow Controller”, in Second International Conference on Power, Circuit and Information Technologyies ICPCIT 2016, Rajarajeswari College of Engineering Bangaluru, Karnataka , 2016.

2016

R. Mahalakshmi and Dr. Sindhu Thampatty K.C., “Damping of Sub-Synchronous Oscillations in DFIG Based Wind farms”, in IEEE International Conference TENCON 2016, Singapore, 2016.

2016

R. Mahalakshmi, Viknesh, J., and,, and Dr. Sindhu Thampatty K.C., “Fuzzy Logic based Rotor Side Converter for constant power control of grid connected DFIG”, in 2016 IEEE International Conference on Power Electronics, Drives and Energy Systems (PEDES), Trivandrum, India, 2016.[Abstract]


Technological advancements has made production of electrical energy more efficient and minimized the consumption of non-renewable sources of energy. Wind energy has been harvested for more than a decade and has been considered to be one of the cleaner methods of producing electricity. This paper focuses on wind electric system connected to the grid. There are different types of wind electric generators such as fixed speed generators (synchronous generators) and variable speed generators which are squirrel cage and slip ring induction generators. Variable speed induction generators are widely chosen in wind electric system. In variable speed induction generators, doubly fed induction generators are mostly used because its rotor transfers the slip power when there is high wind speed velocity, and voltage is injected if the wind velocity is less. This paper proposes a method for controlling the stator power output of DFIG at speeds below synchronous speed using a novel fuzzy logic controller for Rotor Side Converter(RSC). The fuzzy logic rule base is formulated based on wind turbine speed and it controls the amount of rotor/slip power to be injected at appropriate slip frequency by varying the reference signal of the PWM generator, hence maintains the constant power flow from stator to grid. The fuzzy based RSC controller is designed and implemented in the laboratory.

More »»

2016

R. Mahalakshmi, Viknesh, J., and Dr. Sindhu Thampatty K.C., “Mathematical modelling of grid connected Doubly Fed Induction Generator based wind farm”, in 2016 IEEE International Conference on Power Electronics, Drives and Energy Systems (PEDES), Trivandrum, India, 2016.[Abstract]


The day by day increase in electricity demand and depletion of fossil fuels has made the world to think about the renewable energy sources such as solar, wind etc., This paper focuses on the configuration of large Doubly Fed Induction Generator (DFIG) based wind farm connected into the grid. Nowadays DFIGs are more focused in the wind energy conversion systems due to its own advantages. This paper explains the development of a mathematical model of DFIG driven by wind turbine. The turbine generator set is considered as a two mass model and development of the same is discussed. Mathematical modelling of wind turbine, two mass drive train and grid connected DFIG machines are developed by using the dynamic equations. Dynamics of DFIG Rotor Side Converter (RSC) and Grid Side Converter (GSC) are analyzed for further studies with control. The MATLAB simulation results for a 3730W wind farm is explained in this paper, and analyses of various unbalanced conditions on wind farm has been discussed such as rotor short circuit, grid voltage dip and sudden drop in wind speed. Similarly, different rated DFIG machines can be modeled using different machine specifications with the help of developed model.

More »»

2015

Dr. Sindhu Thampatty K.C. and Reghuraj, P. C., “Design and Implementation of RTRL Based Adaptive Controller for TCSC and TCPAR for Stability Enhancement”, in International conference on SMART GRID Technologies ICSGT 2015, Amrita School of Engineering, Coimbatore, Tamilnadu, 2015.

2015

R. Mahalakshmi and Dr. Sindhu Thampatty K.C., “Grid Connected Three Phase Six Level Inverter for Renewable Energy Applications”, in International Conference on SMART GRID Technologies ICSGT 2015, Amrita School of Engineering, Coimbatore, Tamilnadu, Amrita School of Engineering, Coimbatore, Tamil Nadu, 2015.

2015

R. Mahalakshmi, Anuraag, V., Manohar, R., Kumar, A., and Dr. Sindhu Thampatty K.C., “Performance Analysis of DC-DC Quadratic Buck-Boost Converter for solar array”, in IEEE International conference on Technological Advancements in Power and Energy, TAP ENERGY 2015, Amrita School of Engineering, Amritapuri, Kerala, 2015.

2015

, Dr. Sindhu Thampatty K.C., and S., P., “Look-up Table Based Control of Thyristor Controlled Phase Angle Regulator for Power Flow Enhancement”, in International Conference on Advances in Applied Engineering and Technology 2015, ICAAET 2015, Syed Ammal Engineering college, Ramanathapuram, 2015.

2015

M. S., Dr. Sindhu Thampatty K.C., and N., A., “Design and Implementation of a Look up table based TCSC Controller for Power System Stability Enhancement”, in International Conference on Advances in Applied Engineering and Technology 2015, 14-16 May, Syed Ammal Engineering college, Ramanathapuram, 2015.

2015

A. Rajiv, Nathan, V., Ashwanth, A., Rajan, S., and Dr. Sindhu Thampatty K.C., “Modeling and Analysis of Rotor Bearing Fault in a Three Phase Squirrel Cage Induction Motor Using ANSYS R Maxwell 2D”, in International Conference on Advances in Applied Engineering and Technology 2015, ICAAET 2015 , Ramanathapuram, 2015.

2015

Dr. Sindhu Thampatty K.C. and Raj, P. CbReghu, “Adaptive RTRL based hybrid controller for series connected FACTS devices for damping power system oscillations”, in Proceedings of IEEE International Conference on Technological Advancements in Power and Energy, TAP Energy 2015, 2015, pp. 51-56.[Abstract]


This paper presents a novel design of a co-ordinated controller for series connected FACTS devices like Thyristor Controlled Series Capacitor(TCSC) and Thyristor controlled Power Angle Regulator (TCPAR). The scheme can be used for non-linear system control, in which the exact linearized mathematical model of the system is not required, can be used to control many FACTS devices with a single controller. The basis of the proposed design is the Real Time Recurrent Learning (RTRL) algorithm in which the Neural Network (NN) is trained in real time. This requires two sets of neural networks. The first set is a fully connected Recurrent Neural Network (RNN) which acts as a neuro-identifier that provides the dynamic model of the system. The second set of neural network is the neuro-controller, used to generate the required control signals for the thyristors. Simulations results of the system using MATLAB/SIMULINK show that the performance of the system with the proposed controller is better than the conventional PI controllers and GA-based PI controllers. © 2015 IEEE.

More »»

2015

R. Nair, Mahalakshmi, R., and Dr. Sindhu Thampatty K.C., “Performance of three phase 11-level inverter with reduced number of switches using different PWM techniques”, in International Conference on Advancements in Power and Energy (TAP Energy), 2015 , Kollam, 2015.[Abstract]


As compared to conventional inverter topologies like diode clamped and capacitor clamped inverters, the cascaded multilevel inverter has lesser harmonics as well as lower switching stress. The cascaded topology has more number of power switches leading to greater heat losses, larger size, higher cost and more gate drive circuitry. The proposed configuration contains less number of switches and produces lesser harmonics in the output voltage than the cascaded topology. A comparison between four different types of pulse width modulation (PWM) techniques, namely, In-phase disposition (IPD), Anti-phase disposition (APD), Carrier Overlap (CO) and Variable Frequency (VF) PWM methods, has been done. The results have been verified through simulation study in MATLAB/Simulink in order to select the best PWM method that provides minimum THD in the output voltage. An LC filter has been designed to improve the harmonic profile.

More »»

2014

G. A.S. and Dr. Sindhu Thampatty K.C., “Design and Implementation of Series Connected FACTS Devices for Enhancing Power system Oscillation Damping”, in Proc. of the International Conference on Computing, Communication and Energy Systems , 2014.

2010

Dr. Sindhu Thampatty K.C., Nandakumar, M. P., and Cheriyan, E. P., “RTRL Algorithm Based Adaptive Controller for Non-linear Multivariable Systems”, in Proc. of International Conference on Futuristic Computer Applications ICFCA 2010, IISc ,Bangalore, 20-21 March,, 2010.

2009

Dr. Sindhu Thampatty K.C., Nandakumar, M. P., and Cheriyan, E. P., “ANN based adaptive controller tuned by RTRL algorithm for non-linear systems”, in 2009 2nd International Workshop on Nonlinear Dynamics and Synchronization, 2009.[Abstract]


The paper presents artificial neural network (ANN) based adaptive controller for nonlinear systems. A state feedback adaptive control algorithm using fully connected recurrent neural network is employed. The desired trajectory for the on-line training of the neural network is obtained from a reference model. The synaptic weights adaptation of the network is based on real time recurrent learning algorithm (RTRL). Since the synaptic weights are adjusted in real time, this novel method of controller design has potential applications in non-linear systems. Simulation results of the controller applied to a simple non-linear dynamic system demonstrate the effectiveness of the controller.

More »»

2009

Dr. Sindhu Thampatty K.C., Cheriyan, E. P., and Nandakumar, M. P., “Design of a discrete Linear Quadratic Gaussian (DLQG) compensator for SSR damping using a sample invariant discrete model of TCSC”, in TENCON 2009 - 2009 IEEE Region 10 Conference, Singapore, Singapore, 2009.[Abstract]


The paper presents the design of a discrete linear quadratic gaussian (DLQG) compensator for SSR damping which includes a full order Kalman filter to estimate all the states of the system and a full state feedback regulator. The controller is tested on IEEE First Benchmark model for SSR studies. A discrete linear-time invariant (LTI) model of a thyristor-controlled series capacitor (TCSC) in the synchronously rotating DQ reference frame is used in this system in which, the sample invariance is achieved by a simple transformation of the zero sequence variables in the discrete domain. This model of discrete TCSC is then integrated with discretised LTI model of the rest of the system under study. Thyristor firing is based on current synchronised phase-locked loop and the sampling frequency is six times the synchronous frequency. The eigen value analysis is done for this integrated system for different angles of conduction of the thyristor. The modeled system is having 27 state variables including the PLL states. The TCSC model and DLQG compensator design is validated using time domain simulation of the system.

More »»

Publication Type: Conference Proceedings

Year of Publication Title

2019

Dr. Sindhu Thampatty K.C. and Mahalakshmi, R., “Slip Frequency Control Technique for DFIG based Wind Turbine Generators”, International Conference in Advances in Electrical and Computer Technologies 2019, ICAECT 2019. 2019.

2016

Dr. Sindhu Thampatty K.C. and Parol, A., “Mathematical Modelling of Squirrel Cage Induction Generator Based Windfarms for Subsynchronous Resonance Analysis”, JOINT INTERNATIONAL CONFERENCE- ICAIECES-2016 & ICPCIT 2016. 2016.

2015

, Anuraag, V., Manohar, R., and Dr. Sindhu Thampatty K.C., “Performance Analysis of DC-DC Quadratic Buck-Boost Converter for Ssolar Array”, IEEE International conference on Technological Advancements in Power and Energy, TAP ENERGY 2015. 2015.

2014

S. P. Charan, Dr. Sindhu Thampatty K.C., Preethi, P., and T. Balaram, H., “ANN Based Online Bearing Fault Detection System Using Discrete Wavelet Transform”, International Conference on Advances In Engineering And Technology - ICAET 2014. RIT, Roorkee, India, pp. 669 - 677, 2014.[Abstract]


This paper presents neural network based on-line bearing fault detection system using wavelet technique. The presence of fault in a motor can be detected by analyzing its stator current signal which is the basis for the detection of bearing fault in this paper. Discrete Wavelet Transform (DWT) is used to preprocess the stator current signal followed by extraction of features based on calculation of 11 statistical parameters. Artificial Neural Network (ANN) is then trained and tested using the extracted features. The use of ANN as the optimization technique helps in reducing both computation time and error. A system is then built using Virtual Instrumentation consisting of DWT, Feature Extraction and ANN block. The result of the above proposed system is the healthiness of the motor, severity of the fault and type of fault. Various test results and conclusions are presented in this paper.

More »»

2008

Dr. Sindhu Thampatty K.C., P.Cheriyan, E., and Nandakumar, M. P., “Analytical Modeling of Series Compensated Power Systems for SSR Studies”, Proc. of National conference on Emerging Trends and Advances in Electrical Engineering and Renewable Energy, NCEEERE 2008. 2008.

2003

Dr. Sindhu Thampatty K.C. and Sreedharan, S., “Automatic Isolation of Radial Feeders- A Laboratory Model”, Proc. of National conference on Power Conversion and Industrial Controls, PCIC-2003. NSS College of Engineering,Palakkad, India, 2003.

1998

R. S. Kumar and Dr. Sindhu Thampatty K.C., “Environmentally constrained optimum economic dispatch”, Proceedings of EMPD '98. 1998 International Conference on Energy Management and Power Delivery (Cat. No.98EX137)Proceedings of EMPD '98. 1998 International Conference on Energy Management and Power Delivery (Cat. No.98EX137). pp. 265-270, 1998.[Abstract]


This paper presents a general formulation of the optimum economic load dispatch problem in a system with thermal plants taking into account the constraints on emission of sulfur dioxide and oxides of nitrogen. The proposed algorithm is useful to determine the optimum mix-ratio of high sulfur content and low sulfur content fuels, to limit the sulfur dioxide (SO/sub 2/) emission per hour. The emission of oxides of nitrogen (NO/sub x/) is minimised by reducing the output of the generating units with the high ratio of incremental NO/sub x/ emission to incremental fuel cost. The method proposed for considering the pollution constraints is simple, and can easily be incorporated in an existing economic dispatch program. The algorithm is tested on a plant with four generating units, and the results are presented.

More »»

Responsibilities 

  • Coordinated NBA work for the BTech BTech Electrical and Electronics program is accredited for three years
  • NAAC work coordinated in the department
  • Chairman, Board of studies for M Tech, Power Electronics, Embedded systems,Renewable Energy Technologies, Amrita Vishwa Vidyepeetham
  • Member, Board of studies for M Tech Power and Energy, M Tech Control and Instrumentation,B Tech Electrical and Electronics Engineering, Amrita Vishwa Vidyepeetham
  • Reviewer (Int.Journal of Power and Energy Systems-ACTA Press, CSEE Journal of Power and Energy Systems, IEEE Access, Transactions on Electrical Energy Systems-Wiley publications, Int. Journal of Robust and Nonlinear Control - Wiley publications, Int. Journal of Electrical Power components and Systems-Taylor and Francis, IET Int. Journal of Generation, Transmission and Distribution, ASTM Journal of Testing and Evaluation, Int. Journal Renewable Energy-Elsevier, Int. Journal of Electrical Power & Energy Systems-Elsevier, and many international and national conferences)
  • Session Chair in various national and international conferences in India and abroad.
  • Member, Organizing Committee, National Conference on Power Electronics in Sustainable Energy Development (NCPSE 2011), organized by the of Electrical and Electronics Engineering, Amrita Vishwa Vidyepeetham, Ettimadai (December 19-20, 2011).
  • Member, Advisory Committee, International Conference on Smart Grid Technologies, organized by the Electrical and Electronics Engineering, Amrita Vishwa Vidyepeetham, Ettimadai(August 2015).
  • President, International Conference on Embedded Systems (ICES 2014), organized by the Department of Electrical and Electronics Engineering, Amrita Vishwa Vidyepeetham, Ettimadai.
  • Chaired a technical session during the IEEE Region 10 International Conference TENCON 2017, November 6-9, Penang, Malaysia.
  • Chaired a technical session during the IEEE International Conference INDICON December, Amrita Vishwa Vidyapeetham, Ettimadai, Coimbatore, December 16 – 18, 2018, India
  • General co-chair, IEEE International Conference INDICON December, Amrita Vishwa Vidyapeetham, Ettimadai, Coimbatore, India
  • Session chair in different National and International

Best Paper Awards

  1. Aathira .M.J,S. Parvathy, C.Sindhu Thampatty, ”Feedback Linearization Control Technique for Unified Power Flow Controller”, Second International Conference on Power, Circuit and Information Technologies ICPCIT 2016, Rajarajeswari College of Engineering Bengaluru, Karnataka, May 20-21-2016.
  2. N Aarthi, A Vijayakumari, C. Sindhu Thampatty, T. N. Padmanabhan Nambiar, ”Single Stage Grid Connected Solar Micro-Inverter With Two Level Fuzzy Logic MPPT Controller”’, International Conference on Circuit, Power and Computing Technologies, ICCPCT 2017, April 20-21,2017.
  3. Anusri Parol, C.Sindhu Thampatty, Mathematical Modelling of Squirrel Cage Induction Generator Based Wind- farms for Subsynchronous Resonance Analysis, JOINT INTERNATIONAL CONFERENCE – ICAIECES-2016 & ICPCIT 2016, SRM University, Chennai, May 19-21, 2016
  4. C.Sindhu Thampatty, M.P. Nandakumar and Elizabeth.P.Cheriyan. ”RTRL Algorithm Based Adaptive Con- troller for Non-linear Multivariable Systems”, Proc. of International Conference on Futuristic Computer Applications ICFCA 2010, IISc , Bengaluru, March 20-21, 2010.
  5. Sai Charan, P.Preethi, T. Harsha Balaram. K.C.Sindhu Thampatty. ”ANN based Online Bearing Fault Detec-tion System using Discrete Wavelet Transform”, Proc. of the International Conference on Advances in Engineering and Technology (ICAET 2014), Roorkee, India, May 24-25, 2014.