【摘要】 连续高压双极性脉冲方波电压幅值、频率和工作温度与变频调速牵引电机匝间绝缘的寿命有着密切关系。本文对模拟变频电机匝间绝缘的绞线对试样在不同电压幅值、频率、温度下进行加速老化试验,测试其介质损耗角正切值和试样电容随电压的变化特性。通过介质损耗产生机理分析和方波脉冲作用机理研究,结果表明:老化初期,局部放电起始放电电压随电压升高而升高,基本上不受频率的影响,其与空间电荷积累有关。温度在稍微变化(变大)的情况下对绝缘的影响都是很大的。脉冲方波幅值、频率和外界温度具有协同效应,一种因素的增强和减弱都会改变其他因素对绝缘影响的趋势。更多还原

【Abstract】 It has been shown that the waveforms generated by the power converters play a major role in inverter-fed traction motor insulation degradation. Deeper investigation of aging phenomena caused by supply voltage waveforms is needed, especially regarding the relation between aging factors and stress conditions. Accelerated aging tests under different supply voltage waveforms and temperatures were conducted on twisted pairs simulating inter-turn insulation of inverter-fed traction motor. Tan δ and sample capacity were measured under different testing voltages to investigate influence of tan δ and capacity under different aging additions. Based on analysis of dielectric loss and mechanics of square wave pulses, the experimental results show that PDIV is increasing with the increase of voltage amplitude in the early aging stage. PDIV is affected significantly by space charge accumulation under bipolar waveforms, which is almost independent of frequency among three factors. Small change of temperature has a strong impact on insulation. Impulse amplitude, frequency and temperature have a cooperative effect, which shows that strengthening or weakening of each factor will alter trend of other factors effect on insulation.更多还原