Bearing currents and their relationship to PWM drives

Author

Busse, Doyle ; Erdman, Jay ; Kerkman, Russel J. ; Schlegel, Dave ; Skibinski, Gary

Author_Institution

Rockwell Autom-Allen Bradley Co., Mequon, WI, USA

Volume

12

Issue

2

fYear

1997

fDate

3/1/1997 12:00:00 AM

Firstpage

243

Lastpage

252

Abstract

This paper examines AC motor shaft voltages and the resulting bearing currents when operated under pulse width modulation (PWM) voltage source inverters. The paper reviews the mechanical and electrical characteristics of the bearings and motor in relation to shaft voltages and bearing currents. A brief review of previous work is addressed, including the system model and experimental results. The theory of electric discharge machining (EDM) is presented, including component calculations of the system elements. The effect of system elements on shaft voltages and bearing currents are evaluated experimentally and the results compared to theory. A design calculation is proposed that provides the relative potential for EDM. Finally, the paper presents quantitative results on one solution to the shaft voltage and bearing current problem

Keywords

PWM invertors; induction motor drives; machine bearings; AC motor shaft voltages; PWM drives; PWM voltage source inverters; bearing capacitance; bearing current density; bearing currents; bearing threshold voltage; component calculations; electric discharge machining; electrical characteristics; electrostatic shielded induction motor; mechanical characteristics; pulse width modulation; rotor; stator; system model; AC motors; Current density; Insulated gate bipolar transistors; Machining; Petroleum; Pulse width modulation; Pulse width modulation inverters; Rotors; Shafts; Voltage;

fLanguage

English

Journal_Title

Power Electronics, IEEE Transactions on

Publisher

ieee

ISSN

0885-8993

Type

jour

DOI

10.1109/63.558735

Filename

558735