基于模糊自适应PI的并网逆变器相位补偿控制策略

Phase Compensation Control Strategy of Grid-Connected Inverter Based on Fuzzy Adaptive PI

为了解决LCL谐振和模糊自适应PI控制的稳定裕度在高阻抗情况时无法满足系统要求的问题,采用电容电流反馈有源阻尼,即在电容侧并联虚拟阻抗来抑制谐振尖峰,并在模糊自适应PI控制的基础上,引入超前补偿控制策略,提高逆变器在高网络阻抗情况下输出阻抗的相位裕度,保证模糊自适应PI控制的稳定性。仿真结果表明:该方法提高了逆变器等效输出阻抗的相位裕度,保证了系统在高网络阻抗时也能够稳定运行。

In order to solve the problem that the stability margin of LCL resonance and fuzzy adaptive PI control cannot meet the system requirements in the case of high impedance,the capacitor current feedback active damping is adopted,that is,the virtual impedance is connected in parallel on the capacitor side to suppress the resonance spike,and on the basis of fuzzy adaptive PI control,the advanced compensation control strategy is introduced to improve the phase margin of the output impedance of the inverter under the condition of high network impedance,which ensure the stability of fuzzy adaptive PI control.The simulation results show that this method improves the phase margin of the equivalent output impedance of the inverter and ensures the stable operation of the system at high network impedance.