基于模糊PR和PI控制的三相逆变器并网研究

Research on Grid-connected Three-phase Inverter Based on Fuzzy PR Control and PI Control

针对传统PI控制的局限及谐振控制参数固定等问题,提出模糊PR控制,并与PI以并联方式在αβ坐标系下控制三相逆变器并网,从而提高稳态电流质量。模糊PR控制技术,在谐振频率处有无穷大增益,可以无误差跟踪交流量,并根据误差大小和变化率对PR控制的比例参数和谐振系数在线调整。同时利用PI控制具有较大范围的增益和抑制谐波能力,使系统满足最优性能要求。详细分析了PR控制器参数的设计,最后通过仿真实验,将新控制策略和PI控制以及PR和PI控制相比较,证实所提方法的可行性。

According to the limitations of traditional PI control and the fixed parameters of PR control,a new strategy was proposed,which was fuzzy PR control. It controlled grid-connected three-phase inverter combined with PI control in parallel in the two-phase static coordinate. And the strategy can effectively improve the accuracy of compensation of the system and the quality of steady current. The fuzzy PR control,which had an infinite gain at the resonant frequency,could adjust the PR proportional coefficient and resonant coefficient online according to error anderror rate and track the AC control variables without error. In order to help the system meet the requirements of optimal performance,PI control was added which had a large range of gain and harmonic suppression capacity. And the structure and parameters design of PR controller was described in detail. In the end,compared with the PI control,PI and PR control and the new strategy through the simulation experiment,then the proposed method is confirmed as a feasible strategy.