Design And Optimization Of The Concentrating Photovoltaic Sun-tracking Control System

Compared with the traditional solar panels, Concentrating Photovoltaic focus large areas of sunshine to a small area by optical element. After concentration the sunlight can be converted into electric energy by high-efficiency photovoltaic cell. How to track more precisely during sun-tracking process is an important measure to raise the utilization ratio of sunlight. In actual operation, the weak part wouldn’t be replaced more frequently or it will work out. How to track the sun to make the overall system performance best is a real problem.In this dissertation, control system of sun-tracking CPV is designed after studying overseas and domestic research status and actual requirements. Different tracing program is adopt according to different circumstance to achieve the maximum overall system performance.According to regulation scheme, STM32F207 is chosen as the main chip of the control module. Peripheral circuit includes switch input and output circuit, analog input circuit, ethernet interface circuit. The switch input circuit can collects signal from limit switch. Switch output circuit is used for sending signal to transmission mechanism. The analog input circuit collects signals from light module. Ethernet interface circuit can communicate with Ethernet. The hardware circuit of debugging module contains nixie tube, LED, LCD.Some experimental data is acquired from IPC, on the base of the experiment, data is fitted. This Paper acquires history DNI data from automatic weather station. And then get different changing times and relative efficiency of DNI receiving by different steps. At last, a conclusion is drawn: When the sunshine is adequate, the device can debug in 3 steps, on September 15,the changing times reduce by 29% and the DNI recived is 99.1% compared to real-time status, when the sunshine is inadequate, the device can run in 5 steps, on December 15, the changing times reduce by 55% and the DNI recived is 98.24% compared to real-time status.The software design of control module realizes function of self-motion, manual operation, correcting, zero returning at night, returning to urgency position, failure warning and communication. Nixie tube is used for showing time and debugging angle, LED is used for PV array, LCD is used for showing real time data,real-time waveform, parameter setting, working condition, fault message, version information. The debugging module realizing key pressing, interface display, Serial communication. At last the control system realized all the function.In this thesis hardware and software of control and debug module are tested. On the base of test, two system’s joint test is completed including control module and debug module, as well as control module and remote PC. At last the tracking precision error is ±0.1°, which is equal to original PLC system, but the overall system performance increased for the control strategy used.