定子匝间短路时双馈异步发电机电磁转矩的研究

Research on Electromagnetic Torque of Doubly-Fed Induction Generators with Stator Winding Inter-Turn Short Circuit

定子绕组匝间短路故障会引起双馈异步发电机气隙磁场的畸变,从而导致电磁转矩的变化,因此电磁转矩可作为故障特征之一。基于能量法分析定子绕组匝间短路故障前后电磁转矩的变化特征,建立了双馈异步发电机的多回路数学模型,并对其正常和不同程度匝间短路时的电磁转矩进行仿真计算。对仿真结果进行频谱分析,得到了定子绕组匝间短路故障前后电磁转矩谐波分量的变化规律,验证了理论分析的正确性。定子绕组匝间短路故障和电磁转矩的关联特征可以作为诊断定子绕组匝间短路故障的依据。

The stator winding inter-turn short circuit fault can cause the air gap magnetic field distortion of doubly-fed induction generators,which leads to the change of electromagnetic torque. The electromagnetic torque the same as electrical parameters can be used as the fault characteristics. The electromagnetic torque change characteristics before and after stator winding inter-turn short circuit fault were analyzed based on the energy method,and the multi-loop mathematical model of doubly-fed induction generators was established to calculate the electromagnetic torque of the normal and different degree of inter-turn short circuit fault. The harmonic variation characteristics of electromagnetic torque before and after the stator winding inter-turn short circuit fault were obtained by the spectrum analysis of the simulation results,which verified the correctness of the theoretical analysis. The correlation characteristics between stator winding inter-turn short circuit fault and electromagnetic torque could be used as the basis for fault diagnosis of doubly fed induction generators.