永磁同步电机改进无差拍电流预测控制

摘要

In permanent magnet synchronous motor（PMSM） digital control system,the predictive current control algorithm has fast dynamic response and constant switching frequency and is suitable for digital implementation.The deadbeat predictive control algorithm based on Lagrange interpolation formula,is sensitive to motor inductance mismatch.So a constraint relaxing deadbeat predictive control algorithm is proposed.The current offset constraint and output voltage prediction method are modified.The relationship between algorithm stability and motor inductance mismatch is analyzed using root locus method.In case if the inductance mismatch occurs,the system remains stable.The actual motor current could follow the reference current and the closed-loop control is achieved.The robustness of the algorithm is improved.Simulation and experimental results are presented to verify the feasibility and effectiveness of the proposed algorithm.%永磁同步电机数字控制系统的电流预测控制,具有动态响应快、开关频率恒定、适于数字实现等特点。基于拉格朗日插值的无差拍预测控制算法,对电机电感参数失配比较敏感。为此,提出一种改进无差拍预测控制算法,修改了电流偏差约束条件和输出电压预测方法。利用根轨迹法分析了算法鲁棒性与电感参数失配的关系。在电机电感参数发生失配情况下,能够维持系统稳定,实现电机电流的闭环控制,使实际电流跟随给定,提高了算法的鲁棒性。仿真和实验结果验证了分析设计的可行性和有效性。