一种改进型永磁同步电机模型预测电流控制方法

An Improved Model Predictive Current Control Method of PermanentMagnet Synchronous Motor

传统永磁同步电机(PMSM)模型预测电流控制(MPCC)的稳态控制性能与开关频率之间存在矛盾问题,因此在传统MPCC的基础上,提出了一种改进措施。通过将一个电压矢量的电流预测轨迹推广到两个控制周期,并采用不同时刻的电流预测值构建新的成本函数,来评估两个周期内的最优电压矢量,使相邻周期最优电压矢量尽量相同,从而降低逆变器的开关频率。仿真结果表明,相比于传统MPCC,所提方法在相同的控制频率下,可以有效降低开关频率。此外,在开关频率近似相等的情况下,所提方法可以有效改善电流控制性能。

The traditional model predictive current control(MPCC)of permanent magnet synchronous motor(PMSM)has a contradiction between the steady-state control performance and the switching frequency.Therefore,an improved method is proposed based on the traditional MPCC.By extending the current prediction trajectory of one voltage vector to two control cycles,and using the current prediction values at different times to construct a new cost function,the optimal voltage vectors in two cycles are evaluated,so that the optimal voltage vectors in adjacent cycles are as same as possible,thus reducing the switching frequency of the inverter.Simulation results show that compared with traditional MPCC,the proposed method can effectively reduce the switching frequency at the same control frequency.In addition,when the switching frequency is approximately equal,the proposed method can effectively improve the current control performance.