面向单相并网逆变器的改进型二阶广义积分器锁相环控制方法研究OA

With the increasing demand for renewable energy integration,the synchronization accuracy and power quality of grid-connected inverters have a significant impact on grid stability.To improve the comprehensive performance of single-phase grid-connected inverters,the control scheme of the second-order generalized integrator phase-locked loop(SOGI-PLL)is studied.An APF-SOGI-PLL structure combined with an all-pass filter(APF)and a frequency-locked loop(FLL)is proposed to improve anti-interference ability and frequency tracking performance.Proportional odd-harmonic repetitive control is adopted to enhance harmonic suppression capability.A passive damping method is used to suppress resonant peaks and improve system stability.A simulation model of a 1 kW grid-connected inverter is built in Simulink.Simulation results show that the proposed APF-SOGI-PLL can effectively suppress DC offset and achieve fast frequency synchronization under grid frequency fluctuations.The total harmonic distortion(THD)of the grid-connected current is lower than 0.70％,and the comprehensive performance is superior to that of the comparison methods.