低电压穿越条件光伏逆变器模型预测控制研究

低电压穿越条件下要求光伏逆变器能够正常并网,传统并网控制方法难以满足快速性以及低谐波、低漏电流要求。为此,提出一种改进型有限集模型预测控制方法,实现低电压穿越条件下电流快速跟踪控制和漏电流抑制。首先建立电网不平衡条件下准确模型,然后提出改进型有限集模型预测控制,实现并网电流谐波和漏电流的抑制。提出方法能够同时实现漏电流、谐波抑制以及低电压穿越情况电流快速跟踪。仿真结果验证了所提出的算法正确性。

Research on Model Predictive Control of PV Inverter Under Low Voltage Ride Through Condition

Under the condition of low-voltage ride-through,the photovoltaic inverter can be connected to the grid normally.The traditional grid-connected control method cannot meet the rapidity,low harmonics,and low leakage current requirements.Therefore,an improved finite set model predictive control method was proposed to achieve fast current tracking control and leakage current suppression under low voltage ride through conditions.Firstly,the accurate model under the unbalanced condition of the power grid was established,and then the improved finite set model predictive control was proposed to realize the suppression of current harmonics and leakage current in the grid.The proposed method could simultaneously realize leakage current,harmonic suppression,and fast current tracking in low-voltage ride-through conditions.The simulation verified the correctness of the proposed algorithm.