Research On Controlsystem Of Single-phase Grid-connected Photovoltaic Inverter

Energy shortage and environmental pollution problem has become the theme of theglobal problems. It becomes greatly necessary to take measures to develop the techonlogyof the renewable energy generation. In recent yeas, new energy, just as nuclear energy,solar, wind, geothermal drew great attention. With the advantage of extensive, clean andrenewable, the solar energy becomes one of the most utilization prospect of renewableenergy.One of the main utilization of solar energy is the photovoltaic grid-connected system.In this paper, single-phase full-bridge inverter is the object of sutdy, and we mainly analysisthe control strategies. The paper firstly analyzed and compared the structures of the inverter,and seted up the mathematical model of the inverter. Then the paper choose double closedloop control, and completed the MATLAB simulation. Finally, the paper analyzes themodel and the output characteristics of solar cells, and the metheod of IncrementalConductance is adopted to complete the maximum power point tracking control. In addition,the paper also introduce the islanding effect and methods of anti-islanding.The system uses the TMS320F2812to complete the single acquisition and processing,which includes the samping of the grid voltage and grid current, the pruduction of SPWM,the detection of grid-voltage’s. The key task is to finish the phase-locked and feedbackcontrol. The paper realized the frequency-locked control and phase-locked control.