基于D-S证据融合的双馈风力发电机转子匝间短路故障诊断

Fault diagnosis of rotor turn-to-turn short circuit for doubly-fed wind turbine based on D-S evidence fusion

针对双馈风力发电机转子匝间短路因信息单一引起的诊断偏差问题,将D-S证据理论应用到转子匝间短路故障诊断中。根据双馈风力发电机故障前后特征量的变化,选择定子A相电流的(1~2s)f谐波幅值、转子U相电压和电磁转矩的2sf谐波幅值作为证据体。依据D-S证据理论,将以上3种证据体进行信息融合,得到最终的诊断结果;同时,进行双馈风力发电机故障仿真,将信息融合后的诊断结果与单一信息进行比较,验证基于D-S证据融合的双馈风力发电机转子匝间短路故障诊断的高置信度。仿真结果表明,该方法降低了单一特征量不确定性的影响,提高了故障诊断的准确度。

Aiming at the diagnosis deviation caused by single information factor,the D-S evidence theory is applied to the fault diagnosis of rotor turn-to-turn short circuit for doubly-fed wind turbine.According to the change of the characteristic quantities before and after the failure of the doubly-fed wind turbine,the harmonic amplitude of the stator A phase current,the rotor U phase voltage and the harmonic amplitude of the electromagnetic torque are selected as evidences.Based on the theory of D-S evidence,the above three evidences are fused to obtain the final diagnosis results.At the same time,the fault simulation of doubly-fed motor is performed,and the diagnosis results after information fusion are compared with single information to verify the high confidence of the fault diagnosis of rotor inter-turn short circuit of doubly-fed wind turbine based on D-S evidence fusion.The simulation results show that this method reduces the influence of uncertainty of single feature quantity and improves the accuracy of fault diagnosis.