表贴式永磁同步电机有限集模型预测转矩控制成本函数研究

针对表贴式永磁同步电机模型预测转矩控制系统,提出了一种均衡磁链控制和转矩控制的权重系数设计方法,将磁链控制和转矩控制转换为相对误差率的成本函数,从而无需权重系数设计。仿真结果验证以上2种成本函数运行效果良好,但前者对电机参数依赖性较强。由于上述2种成本函数均不含磁链约束项,转矩动态下磁链出现较大的脉动。因此提出了一种含磁链控制约束的成本函数,仿真结果表明,可有效消除磁链脉动。同时,还设计了使用磁链约束项代替磁链控制项的成本函数,但仿真结果表明,虽也可有效消除磁链脉动,但控制效果不及前3种成本函数。

Cost Function of Finite Control Set Model Predictive Torque Control ofSurface Permanent Magnet Synchronous Motor

For finite control set model predictive torque control of surface permanent magnet synchronous motor, a weight coefficient design method which balanced flux linkage control and torque control was proposed. A cost function without weight coefficient was given, which used relative error rates instead of errors to realize flux linkage and torque control. Simulation results showed that the system worked properly by using these two proposed cost functions, but the former strongly depended on motor parameters. As these two functions did not contain flux linkage constraint item, high stator flux ripple would occur under dynamic torque change. Therefore, the third cost function including flux linkage constraint item was proposed. Simulation results showed that it could decrease the stator flux ripple effectively. The fourth cost function was also proposed, which replaced the flux linkage control item with the flux linkage constraint item. Simulation results showed that the fourth cost function could also decrease the stator flux ripple, but the control performances was not as good as the above three cost functions.