1. An evaluation of the electrostatic shielded induction motor: a solution for rotor shaft voltage buildup and bearing current
- Author
-
Busse, Doyle F., Erdman, Jay M., Kerkman, Russel J., Schlegel, David W., and Skibinski, Gary L.
- Subjects
Induction electric motors -- Evaluation ,Electrostatic separators -- Research ,Bearings (Machinery) -- Design and construction ,Rotors -- Dynamics ,Electrical machinery -- Equipment and supplies ,Business ,Computers ,Electronics ,Electronics and electrical industries - Abstract
This paper evaluates a new induction motor, the electrostatic shielded induction motor (ESIM). An ESIM reduces rotor shaft voltages to levels below the bearing lubricant's electric field intensity breakdown level and offers one solution to accelerated bearing wear caused by fluting induced by pulsewidth modulated (PWM) inverters. The paper begins by reviewing shaft voltages and the resulting bearing currents when operated on PWM voltage source inverters. An example of bearing fluting is shown, and system models are presented and discussed. The construction details and test results for several ESIM's are presented. Experimental results show the ESIM solves the electrostatically induced rotor shaft voltage and bearing problem without degrading the electromagnetic performance of the motor. Index Terms - Bearing capacitance, bearing current, bearing current density, bearing voltage ratio, electric discharge machining, electrostatic shielded induction motor, rotor-shaft-to-ground voltage, stator-to-rotor capacitance.
- Published
- 1997