Patent ID: 7719217
Filing Date: 2010-05-18
Classification: G01R,H02P

Abstract:
1. A drive device for a brushless motor, comprising: a plurality of drive circuits that are connected to a plurality of motor terminals of the brushless motor, respectively, each drive circuit having a pair of switching elements that connects a power supply fine of a DC power supply and a ground line to the motor terminals, respectively; a plurality of terminal voltage detecting means that detects terminal voltages of the respective motor terminals, respectively; and abnormality diagnosing means that executes abnormality diagnosis of a motor side circuit after turning off all of the switching elements in the plurality of drive circuits, wherein the abnormality diagnosing means applies a voltage to one of the motor terminals after turning off the switching elements by turning on the switch element on a power supply line side that is disposed in one of the plurality of drive circuits, and takes in the terminal voltages of the respective motor terminals from the respective terminal voltage detecting means as high or low level signals, thereby executing the abnormality diagnosis based on a signal level of the taken terminal voltages.