Induction motor drive systems fed by cables are widely used in industrial applications. However, high-frequency switching of power devices will cause common-mode（CM） voltages during operation, leading to serious CM ...Induction motor drive systems fed by cables are widely used in industrial applications. However, high-frequency switching of power devices will cause common-mode（CM） voltages during operation, leading to serious CM currents in the motor drive systems. CM currents through the cables and motors in the drive systems can cause electromagnetic interference（EMI） with the surrounding electronic equipment and shorten the life of induction motors. Therefore, it is necessary to analyze the CM currents in motor drive systems. In this paper, high-frequency models of unshielded and shielded power cables are formulated. The frequency-dependent effects and mutual inductances of the cables are taken into account. The power cable parameters are extracted by the finite element method and validated by measurements. High-frequency models of induction motors and inverters are introduced from existing works. The CM currents at the motor and inverter terminals are obtained, and the influence of the cable length and cable type on the CM currents is analyzed. There is a good agreement between the experimental results and the CM currents predicted by the proposed models.展开更多
结合隐患排查,对某发电公司6 k V带式输送机控制回路设计进行梳理,提出该公司6 k V带式输送机控制回路存在交直流共用电缆的设计问题,并以《防止电力生产事故的二十五项重点要求》(国能安全[2014]161号)及保护装置、电力系统二次部分等...结合隐患排查,对某发电公司6 k V带式输送机控制回路设计进行梳理,提出该公司6 k V带式输送机控制回路存在交直流共用电缆的设计问题,并以《防止电力生产事故的二十五项重点要求》(国能安全[2014]161号)及保护装置、电力系统二次部分等相关要求为依据,分析交直流共用电缆的危害,详细阐述控制回路中存在的问题,并论述相关的解决措施,以提高设备运行的稳定性,消除不稳定因素,达到设备升级改造的效果,为安全生产提供保障。展开更多
基金Project supported by the National Natural Science Foundation of China(No.51577172)
文摘Induction motor drive systems fed by cables are widely used in industrial applications. However, high-frequency switching of power devices will cause common-mode（CM） voltages during operation, leading to serious CM currents in the motor drive systems. CM currents through the cables and motors in the drive systems can cause electromagnetic interference（EMI） with the surrounding electronic equipment and shorten the life of induction motors. Therefore, it is necessary to analyze the CM currents in motor drive systems. In this paper, high-frequency models of unshielded and shielded power cables are formulated. The frequency-dependent effects and mutual inductances of the cables are taken into account. The power cable parameters are extracted by the finite element method and validated by measurements. High-frequency models of induction motors and inverters are introduced from existing works. The CM currents at the motor and inverter terminals are obtained, and the influence of the cable length and cable type on the CM currents is analyzed. There is a good agreement between the experimental results and the CM currents predicted by the proposed models.
文摘结合隐患排查,对某发电公司6 k V带式输送机控制回路设计进行梳理,提出该公司6 k V带式输送机控制回路存在交直流共用电缆的设计问题,并以《防止电力生产事故的二十五项重点要求》(国能安全[2014]161号)及保护装置、电力系统二次部分等相关要求为依据,分析交直流共用电缆的危害,详细阐述控制回路中存在的问题,并论述相关的解决措施,以提高设备运行的稳定性,消除不稳定因素,达到设备升级改造的效果,为安全生产提供保障。
