Fault Clearing Method for Permanent Magnet Machines

Abstract

A permanent magnet machine (PMM) has a kinetic portion electrically coupled to a power conversion portion. Motive power is provided to the kinetic portion by a torque applied to a motive shaft coupled to a prime mover, such as an aircraft engine or an automobile engine. Generated power is transmitted through a plurality of electrically isolated output feeder cables. When a fault is detected, a switch is opened stopping the flow of current through the feeder cable associated with the faulty circuit. The fault condition is then rendered safe while the prime mover may continue normal operation.

1 . A control circuit for a permanent magnet machine (PMM) having a kinetic portion electrically coupled to a power conversion portion, said control circuit comprising:
 a switch disposed between said kinetic portion and output feeder cables of said power conversion portion; and   a sensor effective to detect a fault condition in one of said feeder cables and in said power conversion portion, said sensor being effective to open said switch when a fault condition is detected.   
     
     
         2 . The control circuit of  claim 1  wherein there are a plurality of said output feeder cables and each said output feeder cable is electrically isolated from other ones of said output feeder cables. 
     
     
         3 . The control circuit of  claim 2  wherein said switch, when open, effectively stops the flow of current through a feeder cable associated with a faulty circuit. 
     
     
         4 . The control circuit of  claim 3  wherein said switch, when open, does not affect the flow of current through other feeder cables not associated with said faulty circuit.