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

Dr. Sindhu M. R. joined Amrita School of Engineering in 2001. She received her B. Tech. (Electrical and Electronics Engineering) and M. Tech.(Power Systems) degrees from Calicut University, Kerala. She has been awarded her Ph. D. from Amrita Vishwa Vidyapeetham. Dr. Sindhu's Ph. D. work was on Adaptive Shunt Hybrid Filter for Power Quality Improvement. A laboratory model of adaptive shunt hybrid filter – adaptive shunt active and adaptive shunt passive filters – was set up and effectiveness is verified with different nonlinear loads.

Dr. Sindhu is carrying out DST funded project on An Intelligent Controller Based Shunt Hybrid Filter for Harmonic Mitigation in Adjustable Speed Drives. She has published 29 research papers in  international journals and conferences. Dr. Sindhu has guided many B. Tech. and M. Tech. projects. She has reviewed many international journals and conference papers. She has also served as Technical Committee Member in various International / National conferences.

She is guiding Ph. D., M. Tech. and B. Tech. students in the area of Power Quality, Power Electronics Applications to Power Systems, FACTS, and Soft Computing.

Publications

Publication Type: Conference Paper

Year of Publication Title

2019

G. K. John, Dr. Sindhu M. R., and NAMBIAR, T. N. P., “Hybrid VSI Compensator for AC/DC Microgrid”, in Proceedings of Conference TENSYMP 2019, 2019.

2018

S. Sindhu, Dr. Sindhu M. R., and Nambiar, T. N. P., “Comparative study of exponential composition algorithm under dynamic conditions”, in Proceedings of 2017 IEEE International Conference on Technological Advancements in Power and Energy: Exploring Energy Solutions for an Intelligent Power Grid, TAP Energy 2017, 2018, pp. 1-6.[Abstract]


Majority of the industrial and commercial loads such as power converters, variable frequency drives, air conditioners, escalators, elevators, etc. incorporate a large number of power electronic devices. These loads introduce dynamic harmonic current, imbalance in the current and varying reactive power demand in the three phase AC mains supply. This paper presents a comparison of four shunt active filtering algorithms. The control algorithms are simulated and analyzed using the MATLAB/Simulink software under different operating conditions. © 2017 IEEE.

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2017

P. Maya, Keerthy, P., Dr. Sindhu M. R., and Kumar, A. G., “Real time implementation for harmonics and reactive power compensation”, in 2017 International Conference on Technological Advancements in Power and Energy ( TAP Energy), Kollam, India, 2017.[Abstract]


<p>Presence of harmonics in the power grid is a major power quality problem. Various techniques are available to compensate both current and voltage harmonics present in the supply. Conventional schemes are based on filtering technique where fundamental current component is separated from distorted load current. This paper deals with simulation and implementation of Synchronous Reference Frame theory based control scheme for shunt active power filter utilized to compensate for the harmonics drawn by a typical nonlinear load. Simulation is carried out in MATLAB/SIMULINK and hardware implementation is done using dSPACE. Results are presented and discussed to validate the performance of the algorithm in real time.

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2017

P. Keerthy, Maya, P., and Dr. Sindhu M. R., “An adaptive transient tracking harmonic detection method for power quality improvement”, in TENSYMP 2017 - IEEE International Symposium on Technologies for Smart Cities, 2017.[Abstract]


Among various power quality issues, presence of harmonics in voltage/current waveforms is a major one. It becomes prominent in smart grids, where renewable energy sources are integrated through power electronic interfaces. Efficiency of harmonic mitigation techniques depends on accurate estimation of fundamental and non-fundamental parts of the waveform. In this paper, an adaptive harmonic estimation technique based on empirical wavelet transform is proposed. This technique is applied to source current waveform measured from a sample power system with nonlinear load. During transients, the algorithm is found to be capable of tracking the change in the fundamental frequency with good time-frequency localization. Simulation of the algorithm is carried out in MATLAB/Simulink. Results are presented and discussed. © 2017 IEEE.

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2017

K. J. Aparna, Dr. Sindhu M. R., and Jisma, M., “Reactive power management of a grid connected SCIG using STATCOM”, in Proceedings of IEEE International Conference on Circuit, Power and Computing Technologies, ICCPCT 2017, 2017.[Abstract]


Wind energy is a significant and promising form of renewable energy. But the main problem associated with grid connection of wind power is its reactive power demand. Squirrel cage induction generators (SCIG) need reactive power for magnetization, which is taken from the grid. With the increase in wind speed, amount of real power generation and hence reactive power demand from source also varies. In this work, STATCOM helps to meet the reactive power needs of induction generator. STATCOM controlled with Instantaneous Reactive Power Theory [IRPT] control algorithm is used for the reactive power management of grid connected SCIG. System performance is studied by means of simulation using MATLAB/Simulink. © 2017 IEEE.

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2016

Dr. Sindhu M. R., Dr. Manjula G. Nair, and S, S., “Photovoltaic Based Adaptive Shunt Hybrid Filter for Power Quality Enhancement”, in 2016 IEEE International Conference on Power Electronics, Drives and Energy Systems (PEDES), 2016.[Abstract]


Power electronic controller based power system equipment are widely used in industrial, commercial and residential sectors. These controllers help in energy saving, but they introduce different power quality issues such as harmonic distortions in current and voltage, voltage sag/swell etc. These power quality issues cause malfunctioning of associated circuits. This paper presents an adaptive shunt hybrid filter where voltage support for DC link capacitor is provided by solar photovoltaic source which improves the power quality by eliminating current harmonics, and improving the power factor. With the help of suitable control algorithm, the filter achieves capability of real power pumping to the grid in addition to harmonic and reactive compensation. The simulation results are carried out with three phase non-linear loads under balanced and/or unbalanced source/load conditions. The results obtained are satisfactory which depicts the effectiveness of the control algorithm and improvement in the power quality with Solar Photo Voltaic integration

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2016

S. Sindhu, Dr. Sindhu M. R., and Nambiar, T. N. P., “Implementation of photovoltaic integrated unified power conditioner for power quality enhancement”, in IEEE International Conference on Power Electronics, Drives and Energy Systems, PEDES 2016, 2016, vol. 2016-January.[Abstract]


This paper presents a photovoltaic (PV) integrated unified power conditioner (UPC) system that provides power quality enhancement as well as real power sharing. The shunt inverter of the PV integrated UPC system provides compensation for the harmonics present in the source current and reactive power while the series inverter compensates for voltage harmonics, voltage sags and swells. A novel control algorithm is used to operate the inverters of unified power conditioner integrated with photovoltaic generation scheme to improve the power quality at the Point of Common Coupling (PCC). The control scheme for PV integrated UPC is verified using MATLAB/ Simulink and validated experimentally using laboratory prototype. © 2016 IEEE.

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2014

Dr. Sindhu M. R., S, K. P., and Nambiar, T. N. P., “Analysis, Estimation and Mitigation of Source Harmonics, Interharmonics in Low Frequency Inductive Loads”, in Proceedings of InternationalConference on Innovations in Information Embedded and Communication Systems , 2014.

2014

Dr. Sindhu M. R., Aneesh, P., Nair, M. G., and Nambiar, T. N. P., “Dynamic Harmonic and Reactive Power Compensation with an Adaptive Shunt Active Filter for Variable Speed Induction Motor Drive”, in International Journal of Power Electronics and Drive Systems, 2014, vol. 4, p. 508.[Abstract]


Major portion of nonlinear loads in industries are contributed by variable speed drives because of their desirable features such as energy saving, smooth control, flexible operation and fast response. These electric drives introduce large amount of current and voltage harmonic distortions at the point of common coupling. These distortions are propagated throughout the system and affect all other loads connected in the system. Hence these distortions are to be mitigated with suitable harmonic filters installed near to the respective load terminals. This paper presents an effective ANN based digital controller for shunt hybrid harmonic filter to provide instantaneous harmonic and reactive compensation. The performance of the adaptive shunt hybrid filter is verified by simulation and experimental studies under steady state and dynamic conditions. The results show that it is an effective, flexible and low rated hybrid filter configuration More »»

Publication Type: Journal Article

Year of Publication Title

2019

S. Sindhu, Dr. Sindhu M. R., and Nambiar, T. N. P., “Design and implementation of instantaneous power estimation algorithm for unified power conditioner”, Journal of Power Electronics, vol. 19, no. 3, pp. 815-826, 2019.[Abstract]


This paper discusses a simple control approach for a Unified Power Conditioner (UPC) system to achieve power quality compensation at the point of common coupling in distribution systems. The proposed Instantaneous Power Estimation Algorithm (IPEA) for shunt and series active power filters uses a simple mathematical concept that reduces the complexity in the design of the controller. The performance of a UPC is verified with a system subjected to voltage distortions, sags/swells and unbalanced loads using MATLAB/SIMULINK. The simulation study shows that a UPC with the proposed control algorithm can effectively compensate for voltage and current harmonics, unbalance and reactive power. The control algorithm is experimentally implemented using dSPACE DS1104 and its effectiveness has been verified. © 2019 KIPE.

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2018

R. V., Maya, P., and Dr. Sindhu M. R., “Optimal position and minimal rating of SVC for voltage stability in power system”, 10, no. 05-Special Issue, pp. 905-911, 2018.[Abstract]


In the current scenario of power system transmission, the demand for more optimal and profitable operation is very essential. One of the major concerns in utilizing electric power is to maintain steady voltage in the system. Improved utilization of existing power system can be achieved through the application of FACTS devices which improves the transmission quality and efficiency of power transmission by supplying inductive or reactive power to the grid. In this paper, an IEEE 5 bus system is considered for detailed analysis and load flow studies is done using Newton Raphson method. The algorithm named Particle Swarm optimization (PSO) is used to detect the best position and minimum rating for SVC to maintain voltage within the stipulated limits. Modelling of SVC is done using MATLAB software. Fuzzy logic controller (FLC) is used for control of SVC. SVC is placed at optimal location and the voltage stability is verified by varying the loads.

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2016

A. D. Krishna and Dr. Sindhu M. R., “Application of static synchronous compensator (STATCOM) to enhance voltage profile in IEEE standard 5 bus transmission system”, Indian Journal of Science and Technology, vol. 9, no. 30, 2016.[Abstract]


Background/Objectives: This paper presents implementation of Static Synchronous Compensator (STATCOM) which can control reactive power through transmission lines in an IEEE standard 5 bus system to meet constraints on bus voltage magnitude, thermal limits and power factor. Methods/Statistical Analysis: This is made possible by appropriately controlling compensation current of shunt compensator. Findings: Simulation results on performance of STATCOM are studied in MATLAB/SIMULINK and validated the effectiveness of the controller. The results show reduction in losses, improvement in power factor and improvement in bus voltage profile are obtained with STATCOM. Application/Improvements: Power flow through the transmission line had improved from 0.014 p.u. to 0.154 p.u.

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2016

A. Krishna D and Dr. Sindhu M. R., “Application of Static Synchronous Series Compensator to Enhance Power Transfer Capability in IEEE Standard Transmission System”, International Journal of Control Theory and Applications, vol. 8, no. 5, pp. 2029 - 2036, 2016.

2016

Dr. Sindhu M. R. and P., K., “Multiobjective Optimal Design and Control of Auto-tuned Passive Filter using Bacterial Foraging Algorithm to improve Power Quality and to minimize Power Losses”, International Journal of Control Theory and Applications, vol. 8, no. 5, pp. 2013 - 2020, 2016.

2016

Dr. Sindhu M. R., “Simplified Control Algorithm for Power Quality Improvement in Industrial Applications”, International Journal of Control Theory and Applications, vol. 8, no. 5, pp. 2021 - 2028, 2016.

2015

P. Krishnapriya and Dr. Sindhu M. R., “Multi-objective optimal design and control of auto-tuned passive filter using bacterial foraging algorithm to improve power quality and to minimise power losses”, International Journal of Control Theory and Applications, vol. 8, pp. 2013-2020, 2015.[Abstract]


This paper presents a multi-objective optimization algorithm based design and control of harmonic filters in a practical system. The selected system is an interconnected system consisting of nonlinear loads. The harmonics injected by the nonlinear loads are propagated through the system and lead to deteriorated power quality at the terminals of all the connected loads. The proposed methodology is selected such as to minimize total harmonic current and voltage distortion introduced into point of couplings and losses and to improve the source power factor. The optimization of the objectives is achieved with bacterial foraging algorithm. Simulation and experimental results verify the performance of the algorithm. More »»

2015

S. Sindhu, Dananjayan, D., and Dr. Sindhu M. R., “Simplified control algorithm for power quality improvement in industrial applications”, International Journal of Control Theory and Applications, vol. 8, pp. 2021-2028, 2015.[Abstract]


This paper deals with the design and development of a control strategy for improving the power quality in the grid. The proposed control algorithm aims at eliminating the harmonics, compensation of the reactive power and power factor correction thereby enhancing the performance of system. The overall system is designed, developed, operated in MATLAB-SIMULINK and system performance is validated by simulation results. More »»

2015

A. D. Krishna and Dr. Sindhu M. R., “Application of static synchronous series compensator (SSSC) to enhance power transfer capability in IEEE standard transmission system”, International Journal of Control Theory and Applications, vol. 8, pp. 2029-2036, 2015.[Abstract]


This paper presents implementation of Static Synchronous Compensator (SSSC) in an IEEE 5 bus system for real and reactive power flow control, to meet constraints on bus voltage magnitude, stability and thermal limits. This is made possible by appropriately controlling the magnitude and phase angle of injected voltage of series compensator. Simulation results obtained after performance study of SSSC in MATLAB/SIMULINK validate the effectiveness of the controller. The comparative study of the simulation results before and after compensation shows reduction in losses, overloading and improvement in bus voltage profile attained with SSSC compensation. More »»

2015

Dr. Sindhu M. R., Arjun R, S, S., and Nambiar, T. N. P., “Power Quality Compensation for an Induction Motor Drive with UPQC”, International Journal of Applied Engineering Research, vol. 10, pp. 15227-15231, 2015.

2015

Dr. Sindhu M. R., Jos, A., S, S., and Nambiar, T. N. P., “Design and simulation of an improved algorithm for three phase shunt active filter”, International Journal of Applied Engineering Research, vol. 10, pp. 844-849, 2015.

2015

Dr. Sindhu M. R. and Nair, M. G., “An Adaptive Shunt Passive filter for Power Quality Improvement”, International Journal of Applied Engineering Research, vol. 10, no. 1, pp. 615-621, 2015.

2015

Dr. Sindhu M. R., A.Nair, A., .V.Satheesan, A., and Kadirimangalam, P., “Power Quality Improvement using Shunt Active Filters for Three Phase Traction Drive”, International Journal of Applied Engineering Research, vol. 10, pp. 35677-35682, 2015.

2015

Sindhu S., Dr. Sindhu M. R., and Nambiar, T. N. P., “An Exponential Composition Algorithm Based UPQC for Power Quality Enhancement”, Procedia Technology, vol. 21, pp. 415 - 422, 2015.[Abstract]


Abstract Power quality is a major concern nowadays due to extensive use of smart controllers based power system equipment. These controlled load behaves with nonlinear characteristics. It introduces distortions in source voltage and source current at the point of common coupling (PCC). The distortions are propagated throughout the system and affects performance characteristics of all other loads connected to the same point of common coupling. Hence mitigation of power quality issues is essential to maintain good power quality at the point of common coupling. This paper deals with implementation of unified power quality conditioner (UPQC) to compensate for power quality issues voltage sag, voltage harmonics and current harmonics. \{UPQC\} is controlled by an exponential composition algorithm (ECA), which is proposed by the author. The performance of \{UPQC\} is examined with a nonlinear load and simulation studies using MATLAB/Simulink verify the satisfactory performance of UPQC. More »»

2015

Dr. Sindhu M. R., Nair, M. G., and Nambiar, T. N. P., “Three Phase Auto-tuned Shunt Hybrid Filter for Harmonic and Reactive Power Compensation”, Procedia Technology, vol. 21, pp. 482 - 489, 2015.[Abstract]


Abstract Hybrid filters are highly recommended for harmonic and reactive compensation in existing installations. Since current harmonic compensation can limit voltage harmonics also to a great extent, shunt hybrid filters are preferred. The traditional shunt hybrid filter consists of shunt passive and shunt active filter. Here, shunt passive filter provides fixed compensation at all load conditions. Therefore, probably at low load conditions, shunt passive filter acts as major consumer. This embarrassing situation can be avoided by replacing traditional shunt passive filter with the shunt auto-tuned passive filter. The shunt auto-tuned passive filter uses an \{ANN\} based controller to select passive filter components to provide adequate harmonic and reactive compensation under all load conditions. Remaining harmonic and reactive power compensation are provided by \{ANN\} based active filter. The performance of the proposed hybrid filter was tested by simulation and laboratory experiments under various source/load conditions and the results show that the proposed shunt hybrid filter is adaptive to varying source/load conditions. More »»

2014

N. Swarupa, Vishnuvardhini, C., Poongkuzhali, E., and Dr. Sindhu M. R., “Power Quality Analysis Using LabVIEW”, International Journal of Research in Engineering and Technology, vol. 3, no. 3, pp. 322-331, 2014.[Abstract]


In the present scenario the ever increasing existence of non linear loads and the increasing number of distributed generation power systems in electrical grids modify the characteristics of voltage and current waveforms in power systems, which differ from pure sinusoidal wave. The target of this paper is to design an accurate measurement system and display the system parameters under distorted system conditions. Harmonics, Sub Harmonics, and Inter Harmonics are measured and displayed using LabVIEW. The voltage and current are sensed using sensors for various loads, which are then interfaced with the PC using DAQ (Data Acquisition) card and displayed using LabVIEW. The Hardware implementation includes setting up of test systems such as diode bridge rectifier and thyristor based converter with various loads such as resistive, inductive and DC shunt motor. Experimental results obtained for various loads and source conditions are cross verified with theoretical analysis. The response obtained in hardware and simulation proves the effectiveness of the system. More »»

2014

Dr. Manjula G. Nair, Dr. Sindhu M. R., and Nambiar, T. N. P., “Dynamic Power Quality Compensator with an Adaptive Shunt Hybrid Filter”, International Journal of Power Electronics and Drive Systems, vol. 4, no. 4, pp. 508-516, 2014.

2013

Dr. Sindhu M. R., Nair, M. G., and Nambiar, T. N. P., “Development of LabVIEW Based Harmonic Analysis and Mitigation Scheme with Shunt Active Filter for Power Quality Enhancement”, International Journal of Recent Technology and Engineering, vol. 2, no. 5, 2013.[Abstract]


Power quality issues, their modeling and mitigation techniques are became hot research topics soon after the introduction of solid state devices in power system. These nonlinear loads, power electronics based ASDs, UPSs are used in industries in large numbers for smooth operation and control. These equipment also introduce power quality issues such as harmonics, reduction in power factor, voltage unbalance, transients etc. These issues cause malfunction or damage of power system equipments. In this paper, harmonics and reactive power are considered as major issues and shunt active power filter is used for compensation. Three phase thyristor converter fed resistive load is considered as test system in this work. Different methods of harmonic analysis and mitigation techniques are surveyed by the author. In this paper, harmonic analysis of source current at the point of common coupling is done using LabVIEW based harmonic analyser, and the reactive and harmonic components of the source current are separated with the help of LabVIEW based intelligent control software. It also generates the switching signals to control voltage source inverter, used as active filter. Simulation and experimental studies using LabVIEW based control system shows the satisfactory performance More »»

2012

N. Surasmi and Dr. Sindhu M. R., “Optimum Allocation of Active Filters In A 4-Bus System Using Genetic Algorithm”, International Journal of Emerging Technology and Advanced Engineering, vol. 2, 2012.[Abstract]


Active power filters (APF) are employed for harmonic compensation in power systems. In this work genetic algorithms (GA) are used for the selection of optimum location of Active filters in power system. The purpose of the genetic algorithm is to minimize the cost of harmonic filters and, at the same time, to reach the harmonic limitations defined by standard IEEE-519. This algorithm is applied to 4-bus interconnected network for fixed harmonic load conditions. The control strategies selected to develop objective function are total harmonic distortion of voltage and current, telephone interference factor of voltage and current, harmonic transmission line loss and active filter current. More »»

2011

Dr. Sindhu M. R., S, S., Nair, M. G., and John, G. K., “Implementation of shunt hybrid filter using ICOS algorithm”, Asian Power Electronics Journal, vol. 5, pp. 7 - 12, 2011.

2011

S. S, Dr. Sindhu M. R., Nair, M. G., and .K.John, G., “Implementation of Shunt Hybrid Filter Using ICOSF Algorithm”, Asian Power Electronics Journal, vol. 5, no. 1, 2011.

2011

Dr. Sindhu M. R., Dr. Manjula G. Nair, and Nambiar, T. N. P., “An ANN Based Digital Controller with Three-Phase Shunt Active Power Filter for Power Quality Improvement”, International Review of Electrical Engineering, vol. 6, no. 6, pp. 2837–2845, 2011.

Publication Type: Conference Proceedings

Year of Publication Title

2017

A. Sanal, Mohan, V., Dr. Sindhu M. R., and Dr. Sasi K. K., “Real time energy management and bus voltage droop control in solar powered standalone DC microgrid”, IEEE Region 10 Symposium (TENSYMP). IEEE, Cochin, India, 2017.[Abstract]


In this paper, different energy management techniques are investigated in solar powered standalone DC microgrid to 1) mitigate real time power mismatches and 2)improve DC bus voltage profile. If the battery state of charge (SOC) is between the maximum and minimum limits, the bidirectional DC-DC converter (BDC) connected to the battery is controlled to maintain DC bus voltage and power balance. Thus, the DC bus voltage is kept under stringent limits by adaptive droop control of BDC. The DC bus voltage set point is varied within the limits to account for SOC based battery management. If the battery SOC is unfit for charging/discharging, load management is deployed to serve the purpose. The boost converter connected to the solar panel (PV converter) is either used for optimal power point tracking (OPPT) or for voltage control in the absence of battery. The methods are investigated on the basis of bus voltage profile and utilization of solar PV source for different ranges of generation and loads using simulation and hardware.

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2014

Dr. Sindhu M. R., R, A., and Nambiar, T. N. P., “Modeling and Control of a three phase Traction Drive and Analysis of Harmonic distortion in Indian Railway Electric Supply System”, Proceedings of International Conference on Innovations in Information Embedded and Communication Systems . pp. 218-222, 2014.

2014

Dr. Sindhu M. R., P, N. T. N., and Balamurugan S, “Development of a Laboratory Model to Teach Power System to Undergraduate Students”, Proceedings of Second National Conference on Power Electronics in Sustainable Energy Development (NCPSE - 2014). 2014.

Faculty Research Interest: