针对电网电压扰动的Vienna整流器复合控制方法

摘要

In this paper, an improved current tracking method is established which is used in the three-phase-four-wire Vienna rectifier.It aims at solving the back-ground harmonic and collapse voltage problems brought by the power grid.Meanwhile, considering the perish current tracking performance and precision in the conventional PI control strategy,a novel control strategy combined PI control strategy with the repetitive control strategy is put forward.In this paper,it makes qualitative analysis on the novel current tracking method,and it also does enough analysis and com-parison about repetitive controller design.The superiority of the novel control method can be shown through contrast of two methods on harmonic suppression characteristics, and finally, an experimental prototype of 3 kW is built.The simulation and experimental results have proved the feasibility and effectiveness of the novel strategy.It has high tracking precision and it can also improve the wave quality of the input current effectively.When the distortion rate of grid current is reduced,the fluctuation of the output voltage is also slighter.So it can maintain perfect output charac-teristics.%针对电网中存在的背景谐波以及电压塌陷等问题,基于三相四线制Vienna整流器,引入了一种改进的电流跟踪方法.同时针对传统PI控制精度不高,电流跟踪效果不好的问题,提出了PI控制与重复控制相结合的新型控制策略.文章对于改进型电流跟踪方法进行了定性分析,并对重复控制器设计进行了充分的分析与比较验证,通过对比得到了复合控制方法在谐波抑制特性方面的优势,最终搭建了3 kW实验平台.仿真与实验结果验证了复合控制方法的可行性和有效性.该方法跟踪精度高,可有效改善网侧电流波形质量.减小网侧电流畸变程度的同时,也减小了直流侧电压的波动,维持良好的输出特性.