Constant power angle control strategy of doubly-fed brushless machine with reluctance rotor

The control strategy has an important effect on the performance and cost of a doubly-fed brushless machine (DFBM) adjustable speed drive system. Therefore, it is necessary to study the key control technique of the DFBM system. Based on the operation principle and mathematical model of a DFBM, a constant power angle control strategy is proposed in this paper. The control system realizes not only soft-starting and speed control over a wide range below and above the synchronous speed, but also adjusts the active and passive power bi-directionally. The system structure, operation principal, control strategy and implementation are introduced. The simulation results of the system performance are also presented in the paper.