基于比例复数积分+重复控制的三相LC并网逆变器控制策略研究

摘要

According to the limitation of traditional PI control,a new control strategy to control three-phase inverter was proposed,which was formed by proportional complex integral (PCI) control and repetitive control in parallel.Proportional complex integral (PCI) control could eliminate the steady-state error in a given condition;repetitive control could suppress the harmonics of grid-connected current and improved the accuracy of steady state control.The new control strategy could be used to control the AC signal and could be directly applied to the threephase abc coordinate system.Without coordinate change,it could save the cost of the inverter control system.On the basis of MATLAB/Simulink platform,a model of grid-connected inverter with LC filter was established and the results of simulation were analyzed to verify feasibility of the strategy.%针对传统PI控制的局限性,采用基于复数域的比例复数积分(PCI)控制与重复控制并联的新型控制策略,其中PCI控制可以在给定条件下消除交流稳态误差,重复控制能够抑制并网电流谐波,提高稳态控制精度.该新型控制策略可以较好地控制交流信号,能直接应用于三相abc坐标系,省去坐标变化环节,节约逆变器控制系统成本.最后通过MATLAB/Simulink仿真平台,建立LC型滤波器的逆变器并网模型,仿真分析证明了该控制策略的可行性.