Closed loop control system for a heliostat field
Publication Type:Conference Paper
Source:Proceedings of IEEE International Conference on Technological Advancements in Power and Energy, TAP Energy 2015, Institute of Electrical and Electronics Engineers Inc., p.272-277 (2015)
Keywords:Central receivers, Closed loop control systems, Closed-loop control, Control systems, energy policy, Heliostats (instruments), IMU, Mechanical actuators, Optical sensors, Piezoelectric actuators, Power towers, Renewable energy resources, Solar energy, Solar thermal energy, Units of measurement, Vibrations (mechanical)
The alarming energy crisis, heightened by the continuing depletion of fossil fuels, accentuates the need for the development of renewable energy technology, knowledge, and infrastructure. A Central Receiver (Power Tower) Solar Energy system uses heliostats (motorized planar reflectors) to continuously reflect direct radiation from the sun onto a central receiver. This paper discusses a novel closed loop control system for a heliostat field. In this system, rough adjustment of the heliostat is performed using an Inertial Measurement Unit (IMU). Precision adjustment of the heliostat is performed by inducing a small mechanical vibration in the heliostat's reflective surface, using a piezoelectric actuator. This vibration creates time-dependent changes in the light waves reflected from the heliostat, which can be detected by photo-sensors surrounding the thermal receiver target. The position of misaligned heliostats can be corrected once they are identified by FFT analysis of the light waves received by the photo-sensors. This technique can, in principle, control thousands of heliostats simultaneously. The control system is coded using MATLAB. © 2015 IEEE.
cited By 0; Conference of IEEE International Conference on Technological Advancements in Power and Energy, TAP Energy 2015 ; Conference Date: 24 June 2015 Through 26 June 2015; Conference Code:115653