基于改进鲁棒重复控制与QPR的光伏电流控制策略

Microgrid photovoltaic current control strategy based on improved robust repetitive control and QPR

为提高微电网中光伏逆变器的功率控制性能,改善光伏发电的并网电流质量,首先建立光储微电网中光伏主电路的状态空间模型,基于此模型,提出一种"嵌入式"的鲁棒重复控制模型,改进传统重复控制中的内模结构,并加入鲁棒补偿器,通过线性矩阵不等式法求得最优配置,以提高控制系统的稳定性能和跟踪精度。然后结合准比例谐振(QPR)控制良好的滤波效果,提出一种基于改进鲁棒重复控制与QPR并联的光伏电流控制策略。最后在RTDS仿真平台上对所提策略进行验证,仿真结果表明,该策略可以有效地提高光伏逆变器的电流跟踪性能和谐波抑制能力,从而验证该策略的有效性和工程应用价值。

In order to improve the power control performance of photovoltaic inverter in microgrid and improve the grid-connected current quality of photovoltaic power generation, the state space model of photovoltaic main circuit in microgrid with PV-ESS is established in this paper. Based on this model, the detailed design process of improved repetitive control and improved robust compensator are given to improve the structure of traditional repetitive control. In order to improve the stability and tracking accuracy of the control system, the robust compensator is added and the optimal configuration is obtained by the linear matrix inequality method. Then, combined with QPR, a photovoltaic current control strategy based on the improved robust repetitive control and paralleling QPR is proposed. Finally, the strategy verification on the RTDS simulation platform shows that this strategy can effectively improve the tracking performance of current and harmonic suppression capability of the photovoltaic inverter, and the effectiveness of the strategy and engineering application value are verified.