变频牵引电机定子绕组内部电压分布特性的研究

分析PWM逆变器驱动的变频牵引电机定子绕组内部电压分布特性,对研究定子绕组绝缘失效和进行绝缘结构设计有重要意义。文章依据变频牵引电机定子绕组结构形式,建立绕组的分布参数电路模型,采用有限差分方法求解得出绕组内部电压分布情况,然后用实际测试结果验证模型的有效性,基于该模型讨论脉冲上升沿时间和电缆对绕组内部电压分布特性的影响。研究结果表明:上升沿时间越短,绕组内部电压分布越不均匀,线圈和匝电压幅值越大,而电缆长度对绕组内部电压分布影响较小,但绕组内部电压幅值增加了约40%。

Study on Voltage Distribution in Windings of Inverter-fed Traction Motor

Analyzing voltage distribution characteristic in windings of inverter-fed traction motor is significant while studying failure mechanism of traction motor insulation and designing insulation structure.Thus,a distribution parameter model has been developed based on winding structure of inverter-fed traction motor.According to the model,finite element differential method is used to get voltage distribution characteristic.Also,simulation results are compared with actual voltage distribution.Then,influences of rise time of pulse and cable is discussed.The results show that the shorter the pulse rise time is,the more uneven the voltage distribution is.Cable length has little influence on voltage distribution characteristic,but has an amplitude increase of 40 percent in coils and turns.