Title :
A Passive EMI Filter for Eliminating Both Bearing Current and Ground Leakage Current From an Inverter-Driven Motor
Author :
Akagi, Hirofumi ; Tamura, Shunsuke
Author_Institution :
Tokyo Inst. of Technol.
Abstract :
This paper presents a practical approach to eliminating both bearing current and ground leakage current from an inverter-driven motor rated at 400 V and 3.7 kW. When the shaft voltage with respect to the motor frame exceeds the dielectric breakdown voltage of thin lubricating grease films in two metal bearings at the drive and non-drive ends, an electrical discharge machining (EDM) current flows through the bearings. A passive electromagnetic interference (EMI) filter can keep the shaft voltage in check, as a result of having eliminated high-frequency common-mode voltage from the motor terminals. Hence, no dielectric breakdown occurs in the grease films, so that no EDM current flows in the bearings. Experimental results verify the viability and effectiveness of the passive EMI filter designed in this paper
Keywords :
AC motor drives; electric breakdown; electrical discharge machining; electromagnetic interference; greases; invertors; machine bearings; passive filters; power filters; shafts; thin films; bearing current elimination; dielectric breakdown voltage; electrical discharge machining current; electromagnetic interference; ground leakage current elimination; high-frequency common-mode voltage elimination; inverter-driven motor; metal bearings; motor terminals; passive EMI filter; thin lubricating grease films; Breakdown voltage; Dielectric breakdown; Dielectric thin films; Electromagnetic interference; Induction motors; Leakage current; Machining; Passive filters; Pulse width modulation inverters; Shafts; Bearing current; common-mode voltage; electromagnetic interference (EMI); ground leakage current; inverters; motor drives; shaft voltage;
Journal_Title :
Power Electronics, IEEE Transactions on
DOI :
10.1109/TPEL.2006.880239
