无刷双馈电动机的无编码器控制

Encoderless Control Method of Brushless Doubly Fed Machines

无刷双馈电机继承了常规双馈电机的优点,如逆变器容量小,整个系统的效率高、成本低等,又省去了滑环电刷,从而提高了可靠性。从绕线转子无刷双馈电机的基本原理出发,推导了其转矩公式,画出矢量图。通过对矢量图和转矩公式的分析,提出一种无编码器的无刷双馈电动机调速控制算法。该算法可以平滑穿越同步转速点,实现控制绕组的零频率控制。对该算法的稳定性问题进行分析,并进行了大量的仿真和实验研究。仿真和实验结果验证了所提出的无刷双馈电动机无编码器控制方法的有效性。

The brushless doubly fed machines （BDFMs） have no slip ring and electric brush which are essential in doubly fed machines, so its reliability can be improved. In this paper, the torque formula of BDFMs was derived and its vector diagram was drawn according to the basic voltage and flux equation. Based on the analysis of vector diagram and torque formula, an encoderless speed control algorithm for BDFMs was presented in this paper. By using the proposed algorithm, the BDFMs can pass through the synchronous speed, which means the control winding can work under the condition of zero frequency. The stability of the algorithm was analyzed. The simulations and experiments were carded out. The simulation and experimental results were presented to demonstrate the effectiveness of the proposed encoderless control method.