开关磁阻电机有限控制集预测转矩控制

Finite control set predictive torque control method for switched reluctance motor drives

针对开关磁阻电机传统直接转矩控制方法转矩脉动大和铜损耗大,并需要设定磁链参考值的问题,提出一种开关磁阻电机有限控制集预测转矩控制方法。首先建立开关磁阻电机离散预测模型,预测转矩未来值;其次提出一种转子扇区划分算法,有效减少了当前时刻候选开关矢量,降低了计算负担;最后通过目标函数在线评估直接选择最小化目标函的最优开关矢量作为控制输出。相对于直接转矩控制,该方法可以有效抑制转矩脉动,减小铜耗,并且该方法仅有一个转矩闭环,无需控制磁链,降低了算法复杂度,更易于硬件实现。与直接转矩控制的对比仿真和实验结果表明,所提出的有限控制集预测转矩控制相比直接转矩控制具有更好的转矩脉动抑制效果和更低的铜损耗。

In order to solve the problem of high torque ripples,copper losses and fixed flux linkage of traditional direct torque control for SRM drive,this paper presents a finite control set predictive torque control method. Firstly,a discrete predictive model of SRM was established and then the future value of electromagnetic torque of the SRM was predicted using this predictive model. Secondly,a sector partition method of rotor position was developed to simplify the finite set of voltage vectors.As a result,the computational burden was sharply decreased. Finally,all torque prediction values were evaluated by a cost function,and consequently,the voltage vector with minimum cost function was selected as the control output. In this way,the proposed FCS-PTC method can minimize the torque ripple and copper losses, and eliminate the closed loop of flux linkage,which is easier to be implemented in practice.Comparative studies were carried out between the proposed FCS-PTC and traditional DTC,and the results show that the proposed control scheme has a better performance for torque ripples suppression and minimization copper losses.