基于矢量作用时间的永磁同步电机预测电流控制

针对以电压源逆变器(VSI)馈电的永磁同步电机(PMSM)驱动系统,提出一种基于矢量作用时间的预测电流控制策略。从拓展有限控制集和改变最优电压矢量选择方式的角度出发来改善系统的稳态性能。首先通过加入虚拟电压矢量的方式拓展有限控制集,并依据在每个扇区内各矢量对d轴电流增、减作用的不同来优化有限控制集。其次令下一时刻的预测电流值等于其期望值,从而可获得每个矢量作用时到达d、q轴电流期望值的矢量作用时间。利用各矢量的作用时间来衡量其对d、q轴电流的作用效果,以此代替传统预测电流控制中的电流预测环节。并依靠矢量作用时间来选择最优电压矢量,这样可以有效解决占空比调制环节难以有效发挥作用的问题。最后通过实验对所提算法的可行性与有效性进行了验证。

Predictive Current Control for Permanent Magnet Synchronous Motor Based on Operating Time of Vector

In this paper,a predictive current control based on the operating time of vector is proposed for voltage source inverter(VSI)-permanent magnet synchronous motor(PMSM) drive system.The steady state performance of the system is improved by extending the finite control set and changing the selection method of the optimal voltage vector.Firstly,the finite control set(FCS) is extended by adding the virtual voltage vectors and optimized according to the different increasing and decreasing effects of vectors on the d-axis current in each sector.Then,in order to obtain the d,q-axis operating time of each vector,making the predictive d,q-axis current values of next time equals to their expected values.The d,q-axis operating time of each vector are used to evaluate the action effects on d,q-axis current,which replaces the predictive current part in the traditional model predictive current control.Meanwhile,depending on the operating time of vector to select the optimal voltage vector,the proposed method can solve the problem that the duty cycle doesn't work effectively in the predictive current control with duty cycle modulation.Finally,the feasibility and effectiveness of the proposed approach are verified by experiments.