The motor is one of the most common machines. It is a device that converts electromagnetic energy into machine energy. It is widely used in various scales. In the process of energy conversion of high-power motors, some simple and huge factors may cause the motor Shaft currents occur at different levels, especially high-power motors, high-voltage motors and ordinary motors. Sometimes due to the shaft current, the bearings of the variable-frequency motor will burn out.
The necessary conditions for current generation are voltage and closed circuit. To eliminate the shaft current, from a theoretical point of view, one method is to control or even eliminate the shaft voltage, and the other is to cut off the closed circuit; in actual production, different motor manufacturers In view of the different operating conditions, the adopted methods are endlessly communicated. According to the method of cutting the circuit, the method of recycling the insulated bearing sleeve, the insulated end cover, the insulated bearing, or the insulation of the bearing position.
In order to reduce the hazard of shaft current from the foundation, the fairness of the motor design plan of the high-power motor manufacturer and the suitability of the manufacturing process are all necessary for the design. The design plan and the lean control of the process manufacturing are more than the various methods in the later period. Economical and reliable.