Failure mechanism of variable frequency drives in ungrounded distribution systems
This work investigates an actual violent failure of a number of variable frequency drives that were supplied by an ungrounded power source. It was noted that when a phase-to-ground fault was manifested in one of the motors, all the VFDs were destroyed except the one that is connected to the motor where the fault occurs. Circuit analysis and simulations using PSpice was carried out in an effort to explain the cause of such destruction. It is found that the inverters used in this facility were not designed for ungrounded power supplies, and the cause of such failure is the presence of an EMI capacitor filter that is placed between the DC link midpoint and ground.
Capacitors; Electromagnetic interference; Failure analysis; Fault location; Invertors; Motor drives; Power distribution faults; Power distribution reliability; Power filters; Power supply quality; Power system simulation; Underground distribution systems
Computer Engineering | Electrical and Computer Engineering | Engineering
Use Find in Your Library, contact the author, or interlibrary loan to garner a copy of the item. Publisher policy does not allow archiving the final published version. If a post-print (author's peer-reviewed manuscript) is allowed and available, or publisher policy changes, the item will be deposited.
Venkateswaran, M. M.,
Failure mechanism of variable frequency drives in ungrounded distribution systems.
2004 11th International Conference on Harmonics and Quality of Power