Why motor shaft current will produce?

The shaft of the motor-bearing seat-base the current in the circuit is called shaft current.The cause of shaft current:(1) the asymmetry of magnetic field;(2) in the power supply current harmonic;(3) the manufacture, the installment is not good, caused by rotor eccentric air-gap uneven;(4) acmotortrading.blogspot.com the detachable stator core has a gap between two semicircle;(5) with fan-shaped lay in the number of the spell of the stator core piece choose not appropriate.Hazard:Make motor or ball bearing surface erosion, shape process, microporous worsen bearing operation performance, the friction loss and heat increase, resulting in Bearing burn out.Prevention:(1) eliminating pulsating pumps magnetic flux and power harmonic (as in the inverter output side reactor with communication);(2) the motor design, insulation, the ac alternators 220v sliding bearing housings and base of the rolling bearing outer ring and end cover insulation.