基波电压线性化的永磁同步电动机控制策略

Control strategy for permanent magnet synchronous motor in fundamental voltage linearization

针对轨道交通永磁同步牵引系统全速度范围内的调速性能,在低速区采用异步调制模式,在中高速区采用不同分频的同步调制模式;为了满足各种模式之间的平滑过渡,提出了对基波电压进行线性化处理的策略,并将所提方法与恒转矩区的最大转矩电流控制、恒功率区的弱磁控制相结合,实现了轨道交通永磁同步牵引系统全速度范围内的调速。在充分利用开关频率的同时,提高了直流电压的利用率,可以保证三相电流和线电压波形的对称性,减少谐波含量,降低尖峰电流;同时对基波电压进行线性化处理后,各个模式之间的切换及负载突变时,系统稳定、抖动小。通过仿真及地面试验,验证了本文提出方案的有效性。

For the permanent magnet synchronous traction rail traffic system, to improve the speed regulation performance during full speed range, asynchronous and synchronous modulation mode were respectively applied in low speed and high - middle speed regions. To ensure a smooth switch between different modes, a strategy of linearization of the fundamental voltage was proposed. Moreover, by combining with other control strategies, that is Maximum torque current control method in constant torque region and Weakening control method in constant power region, it can realize successfully the speed regulation dur- ing full speed rang for the permanent magnet synchronous traction rail traffic system. The advantages of the proposed method include： the utilization of switching frequency and DC voltage is further improved. The symmetry of three - phase current and line voltage waves was realized. Harmonic content and peak current were reduced. Furthermore, the system is more stable when modes switch or load mutation by using linearization of the fundamental voltage. The simulations and actual tests verify the effectiveness of the proposed scheme.