A solar panels automatic tracking system based on OMRON PLC

Aiming at low density of solar energy, intermittent of solar ray, changing light intensity and direction with time, the paper studies maximum power point of photovoltaic module based on OMRON PLC. The system designed the hardware and software, and the hardware included PLC I/O configuration, the signal processing unit, the comparison circuit of photosensitive resistance for detecting ray strength, photovoltaic modules and switch power supply; and the software included PLC programs for monitoring, and PC programs for monitoring and handling data. The photovoltaic module in the system can track the sun simultaneously, then the maximum sun energy will be obtained, which has effectively improved the utilization ratio of solar energy and efficiency of photovoltaic power generation system, and has reduced the cost of grid-connected PV power generation with significances of theories research and application values of applications promotion.