基于伏秒的反激式光伏微逆变器的仿真研究

Simulation Study of Flyback Photovoltaic Micro Inverter Based on Volt Seconds

针对传统反激式光伏微逆变器因2倍频电压纹波引起的进网电流畸变的问题,提出了1种用于励磁电感电流断续模式下反激式光伏微逆变器的基于伏秒的控制方法.根据谐波抑制策略,对反激式光伏微逆变器进行小信号建模,利用扫频验证建模的正确性.通过推导变压器参数的设计准则,结合变压器参数与输入电压调节范围和损耗的关系对其进行优化设计并进行仿真.结果证明了所提控制方法的准确性,与传统开闭环电流控制方法相比,输出电流的THD更低,达3.783%.

In response to the problem of grid current distortion caused by double frequency voltage ripple in traditional flyback micro inverters,a volt second based control method for flyback micro inverters in intermittent excitation inductor current mode is proposed.According to the harmonic suppression strategy,small signal modeling is performed on the flyback micro inverter,and the correctness of the modeling is verified using frequency sweep.By deriving design criteria for transformer parameters and considering the relationship between transformer parameters and input voltage regulation range and losses,the optimization design and simulation are carried out.The results demonstrate the accuracy of the proposed control method.Compared with traditional open loop current control methods,the THD of the output current is lower,reaching 3.783%.