基于无源化方法的双馈感应风力发电机功率控制

POWER CONTROL FOR DOUBLE-FED INDUCTION WIND GENERATOR USING PASSIVITY METHOD

针对目前感应电机无源性控制方法的不足,提出一种基于无源化方法的双馈感应风力发电机功率控制方案。该方案从功率控制的角度考虑,设计新的状态期望值计算方法。根据定子端有、无功功率目标值直接计算出定子电流的期望值,从而实现有功功率和无功功率的独立控制;然后结合定子电压方程计算出转子电流参考值。此计算方法无需给定定子磁链,从而可避免给定定子磁链不准确而引起定、转子电流及定子磁链跟踪误差的问题;设计定子电流反馈控制器,不仅可改善系统的无源性,且可提高定子电流和定子磁链的跟踪性能。仿真结果表明所提控制策略是有效的。

Passivity control for induction generator has become a research hotspot in the past few years. Aiming at shortage of existing methods, a power control strategy for double-fed induction wind generator （DFIG） using passivity was presented in this paper. In the control scheme, a new computing method for state expected values was introduced based on the perspective of power control. According to the target of active power, reactive power, the expected values of stator currents were obtained, so that the independent control of active power and reactive power was achieved; and then the expected values of stator current were calculated combining with the stator voltage equation. As a result of this method without given stator flux expectations, the problems of stator and rotor current error caused by the inaccurate given stator flux could be avoided; a stator current feedback controller was designed, which could improve the system passivity and the tracking performances of stator current and stator flux. The simulation results show that the proposed control strategy is effective.