无刷双馈电机直接转矩控制转矩脉动最小化

Torque ripple minimization strategy for the direct torque control of brushless doubly-fed machines

针对无刷双馈电机直接转矩控制系统转矩脉动大的问题,依据模糊控制理论,研究了基于模糊控制的无刷双馈电机直接转矩控制系统。将转矩误差、磁链误差、扇区作为模糊控制器的输入,采用模糊控制器自动合理地选择电压空间矢量,取代传统的开关矢量表,同时将磁链圆划分为24个扇区。Matlab环境下的仿真结果表明,与传统的无刷双馈电机直接转矩控制系统相比,有效地减小了稳态时的转矩脉动,并且改善了定子磁链波形,使定子电流波形更接近于正弦。系统在启动、负载扰动等情况下仍然保持了良好的动态性能。在DSP控制系统中实现时,可经相应的离散化后通过查表运算实现模糊控制,实现算法简单,且具有良好的实时性。

To deal with the large torque ripple of the direct torque control for Brushless Doubly-fed Machines （BDFM） control system, an application of the direct torque control for BDFM based on fuzzy logic is proposed. The control system is set up with the fuzzy controller to replace the conventional switching table of inverter voltage vectors. In this control system, the input signals of fuzzy controller are torque error, control winding stator flux error and the rotor position. This fuzzy controller can be able to select the switching table of inverter voltage vectors more reasonably according to the theory of fuzzy logic. The simulation results indicate that this control system compared with conventional direct torque control system can efficiently reduce the torque ripple and improve the waveforms of stator current and stator flux. This control system also has high dynamic and static performance in different operation conditions. In the DSP control system, fuzzy logic control algorithm can be easily realized by the corresponding discrete fuzzy logic looking-up tables. This control algorithm is simple and can promote the real-time capability.