摘  要：针对单纯PI控制无法实现无静差的缺点，对分布式并网发电中逆变器的控制进行改进，提出一种基于PI控制和改进的重复控制相结合的新型复合控制策略。PI控制则使系统具有快速的动态响应能力；改进的重复控制可以有效地改善系统的稳态输出波形质量。仿真表明，新的控制策略可有效改善并网电流波形，基本实现并网电流无差跟踪，同时能保证逆变器输出电流与电网电压同频同相。
关键词：分布式发电；并网；改进的重复控制；复合控制

Abstract: Aiming at solving the disadvantages that traditional PI control can not realize tracking without steady-state error. This paper engaged in improving the control of distributed generation grid-connected inverter, presented a novel composite control strategy which combines PI control with improved repetitive control. The PI control made the inverter achieve fast dynamic response.By the improved repetitive control output waveform of steady current of converter was improved greatly. The simulation results show that the novel control strategy has obviously improved the grid-connected current waveform and realized tracking with zero-error. Also, it can guarantee the wave of grid-connected current has the same frequency and phase as the utility voltage.
Key words: distributed generation; grid-connected; modified repetitive control; composite control