PWM脉冲电压下变频电机匝间绝缘研究

Study on Inter-turn Insulation of Inverter-Fed Motor under PWM Impluse Voltage

定子绕组匝间绝缘失效是导致变频电机损坏的主要原因。以湘电1 650 V变频电机匝间绝缘结构为研究对象,对匝间绝缘用FMB-40线对和耐电晕FCRMB-40线对进行高频方波脉冲老化试验,分析两者老化前后介质损耗与局部放电的变化。结果表明:施加幅值2.0 k V、频率20 k Hz的方波脉冲电压老化1 000 h后,两种结构都通过了老化试验。其中耐电晕FCRMB-40线对的表现较优,用于1 650 V变频电机匝间绝缘具有更佳的电气可靠性。

The main damage reason of inverter-fed traction motor is the failure of inter-turn insulation. Us- ing the inter-turn insulation of 1 650 V inverter-fed traction motor from XEMC as research object, we con- ducted ageing experiment on the FMB-40 enameled wire and anti-corona FCRMB-40 enameled wire un- der high frequency square wave pluse, and their dielectric loss and partial discharge before and after age- ing were analyzed. The results show that two types of structure all pass the ageing test for 1 000 h un- der square wave impulse voltage with voltage amplitude of 2.0 kV and frequency of 20 kHz. The dielec- tric loss, partial discharge intensity and residual breakdown voltage of the anti-corona FCRMB-40 show better than that of the FMB-40, and the anti-corona FCRMB-40 used in 1 650 V inverter-fed traction mo- tor would have more electrical reliability.