SISO amplitude-phase impedance calculation method and system for single-phase grid-connected inverter in polar coordinate system

The invention discloses an SISO amplitude-phase impedance calculation method and system for asingle-phase grid-connected inverter ina polar coordinate system. An amplitude-phase admittance model of the single-phase grid-connected inverter in the rotating polar coordinate system is firstly built by considering the influence of a current inner loop, a phase-locked loop, time delay and power grid impedance of the single-phase grid-connected inverter, then, an amplitude-phase impedance model in an SISO form is deduced through matrix transformation, and the accuracy of the established model is verified through simulation and experiments. 本发明公开了一种极坐标系下单相并网逆变器SISO幅相阻抗计算方法及系统，考虑单相并网逆变器电流内环、锁相环、延时以及电网阻抗的影响，首先在旋转极坐标系下建立单相并网逆变器的幅相导纳模型，然后通过矩阵变换推导出SISO形式的幅相阻抗模型，并通过仿真与实验验证了所建模型的准确性。