基于PI与重复复合控制的并网整流器并网系统研究

Research of Grid-connected Rectifier Based on the PI and Repetitive Control

在详细分析三相三电平桥式并网整流器工作原理的基础上,针对传统电流内环单PI控制策略难以实现对交流信号无误差跟踪且谐波抑制能力较差等问题,提出并采用了PI控制与重复控制相结合的复合策略实现了并网整流器的单位功率因数控制,给出了详细的理论分析与设计方案。为验证文中控制策略的可行性,进一步构建了完整的系统仿真模型与实验平台。实验结果表明:文中设计并采用的控制策略可有效提升系统性能,输入电流THD得到显著改善,该控制策略结构简单,且便于数字化实现,对于并网整流器的设计具有一定参考意义。

On the basis of detail analysis of the working principle of three-phase three-wire grid rectifier,in viewof the problem which the ability of harmonic suppression is poor and it is difficult to tracking the AC signal withouterror when the current inner loop adopts single PI control strategy,the control strategy named PI and repetitivecompound strategy was put forward to achieve the interconnected rectifier unit power factor control.The detailedtheoretical analysis and design were given.To test and verify the feasibility of the control strategy,a complete systemsimulation model and experimental platform were further built,the experimental results show that the design and thecontrol strategy can effectively improve the system performance,the input current THD get improved significantly,thecontrol strategy is simple and easy realized in the digital control,provides an important reference for the design ofgrid-connected rectifier.