低压散绕变频电机绝缘薄弱点定位方法研究  

Study on the location method of insulation weak point for low-voltage random-wound inverter-fed motor

作　　者：郭厚霖 王鹏[1] 林海 罗英露 马世金 Guo Houlin;Wang Peng;Lin Hai;Luo Yinglu;Ma Shijin(College of Electrical Engineering,Sichuan University,Chengdu 610065,China;Xiangyang CRRC Motor Technology Co.,Ltd.,Xiangyang 441047,China)

机构地区：[1]四川大学电气工程学院,成都610065 [2]襄阳中车电机技术有限公司,襄阳441047

出　　处：《仪器仪表学报》2021年第11期140-149,共10页Chinese Journal of Scientific Instrument

基　　金：国家自然科学基金(51977134)项目资助。

摘　　要：根据IEC相关标准,采用重复脉冲和正弦电压测定变频电机绝缘系统PDIV,是评估低压散绕变频电机绝缘性能的关键手段。然而,现行IEC标准难以识别定子绕组绝缘薄弱点。对此,联合重复脉冲和正弦PDIV离线测试技术,提出定位变频电机绝缘薄弱点的"三步法":首先采用重复脉冲电压测定电机匝间绝缘PDIV;然后利用正弦电压测定相间及主绝缘PDIV,并与匝间PDIV对比,确定电机绝缘薄弱点;最后通过测试电机在不同接地方式下的PDIV,可定位绝缘薄弱点是否位于定子绕组首端。另外,通过定子绕组电压分布仿真、3个商用电机薄弱点识别及电机寿命实验,综合验证了上述方法的可行性。此研究可实现变频电机绝缘薄弱点的有效定位,提升电机绝缘潜在风险诊断效率。According to the relevant standards of the international electrotechnical commission(IEC),the utilization of pulse and sinusoidal voltages to determine the partial discharge inception voltage(PDIV)of the inverter motor insulation system is a key method to evaluate the insulation performance of low-voltage random-wound inverter-fed motors.However,the current IEC standard is difficult to identify the stator insulation weakness.To solve this problem,combines the PDIV off-line test technology under the repetitive pulse and the sinusoidal voltage,a three-step method is proposed to locate the weak point of the inverter-fed motor insulation.Firstly,the repeated pulse voltage is used to measure the PDIV of turn-to-turn insulation in the motor.Secondly,the PDIVs of phase-to-phase insulation and main wall insulation are measured by the sinusoidal voltage,which are compared with the turn-to-turn insulation PDIV.In this way,the weak point of the motor insulation can be determined.Finally,through the PDIV test in different grounding modes of the motor,it is possible to locate whether the weak point of insulation is located at the stator winding head.In addition,by simulation of stator voltage distribution,weak point identification of three commercial motors and corona life test of motors,the feasibility of the above method is comprehensively verified.The research can effectively locate the insulation weakness of the inverter-fed motor.And the efficiency of diagnosing potential risks in the motor insulation is improved.

关 键 词：变频电机 局部放电起始电压 绝缘薄弱点 主绝缘 匝间绝缘 相间绝缘 

分 类 号：TH17[机械工程—机械制造及自动化] TM85[电气工程—高电压与绝缘技术]