低气压方波电压下多电飞机电机绝缘局部放电研究  

Research on Partial Discharge of More Electric Aircraft Propulsion Motor Insulation Under Low Pressure and Square Wave Voltage

作　　者：孙浩 王亚林[1,2] 范路[1,2] 丁毅[1,2] 朱昕阳 尹毅 SUN Hao;WANG Yalin;FAN Lu;DING Yi;ZHU Xinyang;YIN Yi(Department of Electrical Engineering,Shanghai Jiao Tong University,Shanghai 200240,China;Key Laboratory of Control of Power Transmission and Conversion,Shanghai Jiao Tong University,Shanghai 200240,China)

机构地区：[1]上海交通大学电气工程系,上海200240 [2]上海交通大学电力传输与功率变换控制教育部重点实验室,上海200240

出　　处：《高电压技术》2023年第2期565-576,共12页High Voltage Engineering

基　　金：国家自然科学基金(52007114)。

摘　　要：随着宽禁带电力电子器件与电机技术的发展,推进电机的比功率密度与容量大大提高,能够更好的满足多电飞机推进的需求,但极端环境条件(低气压、高温)与具有高d U/dt(快速上升、下降时间)的高频方波电应力更加容易引发局部放电(partialdischarge,PD),加速电机绕组绝缘材料的老化,导致电机系统失效。局部放电检测是衡量绝缘可靠性的重要手段,但与正弦电压下局部放电检测方法不同,具有高d U/dt的方波电压在上升沿和下降沿会引发强烈电磁干扰,极大地影响局部放电检测。为了解决此问题并研究低气压下多电飞机电机绝缘局放特性,提出基于特高频下混频技术和硅光电倍增技术的多电飞机推进电机绝缘局部放电联合检测方法,有效解决了高d U/dt方波下的电磁干扰问题。针对飞机实际运行工况,利用所提出的检测方法测量了不同气压下(低至20 kPa),施加方波电压时电机绝缘试样的局部放电特性,并与施加正弦电压的情况进行对比。分析了电机绝缘气–固复合绝缘的界面电荷弛豫过程,发现重复方波电压下界面弛豫电荷与局放残余电荷对瞬态电场的存在拮抗作用。提出了不同气压高d U/dt方波下局部放电起始电压的改进Paschen公式,并分析了低气压对快速方波下电机绝缘局放特性的影响规律,为多电飞机推进电机绝缘性能评估和优化设计提供参考。Due to the development of wide-bandgap power electronic devices and motor technology,the specific power density and capacity of electric aircraft motors have been greatly improved,which can better satisfy the needs of more electric aircraft propulsion.However,extreme environmental conditions(low pressure,high temperature)and high-frequency square wave electrical stress with high d U/dt(fast rising/falling time)are more easily to cause partial discharge,which may accelerate the aging of insulating materials and lead to failure.PD detection is an important approach to evaluate the insulation reliability,whereas,unlike the PD detection under sinusoidal voltage,the square wave voltage source with fast rise time can cause strong electromagnetic interference,which greatly interferes with PD detection.In order to solve this problem,this paper introduces a combined detection method for partial discharge of more electric aircraft propulsion motor insulation based on UHF down-mixing method and silicon photomultiplier photoelectric method,which has strong anti-electromagnetic interference ability.To test the actual operating conditions of the aircraft,the proposed method is used to measure the partial discharge of the motor insulation sample when a square wave voltage is applied under different air pressures(down to 20 kPa).The interfacial charge relaxation process of solid-gas composite insulation of motor insulation is analyzed,and the antagonistic effect of interfacial relaxation charge and local residual charge on transient electric field under repeated square wave voltage is proposed.The improved Paschen formula of partial discharge initial voltage under fast square wave with different air pressure is obtained,and the influence law of low air pressure on local discharge characteristics under fast square wave is analyzed,which provides reference for insulation performance evaluation and optimization design of propulsion motor for more electric aircraft.

关 键 词：局部放电 多电飞机 特高频 下混频 硅光电倍增 

分 类 号：V272[航空宇航科学与技术—飞行器设计]