高频脉冲对变频电机匝间绝缘起始放电及耐电晕寿命影响机制研究

变频电机是工业生产的核心设备，也是驱动高速铁路、新能源汽车和未来电动飞机等重要负载的心脏。宽禁带电力电子器件替代传统硅基器件是提升变频电机功率密度和能量转换灵活性的必然选择，而宽禁带电力电子器件下的绝缘评估技术是解决变频电机绝缘系统可靠性问题的关键。本项目拟在高频脉冲下，研究脉宽调制关键参数及环境因素对匝间绝缘起始放电产生、耐电晕寿命的影响规律和机制。采用匝间绝缘起始放电光电倍增及特高频测试技术，结合初始电子累积概率分析和放电发展过程仿真，探明脉冲电压下起始放电产生和转变机制、环境因素影响机理，提出变频电机匝间绝缘起始放电通用预测方法，以期为变频电机绝缘性能评估提供新手段。利用高频脉冲下耐电晕测试平台和表面电荷光电测试技术，结合绝缘破坏宏观表征及微观理论，揭示高频脉冲及环境因素对绝缘破坏影响机制，构建宽禁带电力电子器件下变频电机匝间绝缘寿命评估模型，有望为变频电机绝缘寿命预测提供新思路。

Inverter-fed motors are the core equipment for industrial production and the heart of important loads such as high-speed railway, new energy vehicles, and future electric aircraft. The replacement of conventional silicon-based devices by wide band gap power electronic devices is an inevitable choice to improve the power density and energy conversion flexibility of inverter-fed motors. The insulation evaluation technology under wide band gap power electronic devices is the key to solve the reliability problems of inverter motor insulation systems. This project intends to study the influence and mechanism of the key parameters of pulse width modulation and environmental factors on the initial discharge and corona resistance performance of the turn-turn insulation under high-frequency impulses. The influence of impulsive voltage and environmental factors on initial discharge generation and transformation mechanism will be investigated by using the turn-turn insulation initial discharge photomultiplier, ultra-high frequency test technology, initial electron accumulation probability analysis and discharge development process simulation. A general discharge inception voltage prediction method for turn-turn insulation will be proposed to provide a new methodology for the insulation evaluation of inverter-fed motors. Resorting to the corona resistance test platform and surface charge photoelectric test technology under high frequency pulse, combined with the macroscopic characterization and microscopic theory of dielectric breakdown, the influence of mechanism of high frequency impulses and environmental factors on insulation aging will be revealed to set up an endurance prediction model that is expected to be used for insulation systems of inverter-fed motors driven by wide band gap power electronic device.