INVERTER AND MOTOR DRIVE DEVICE WITH FAILURE DETECTION FUNCTION OF POWER LINE

摘要

PROBLEM TO BE SOLVED: To provide a motor drive device capable of detecting the failure that current does not normally flow through a motor and locating the location of the failure.SOLUTION: A motor drive device according to an embodiment comprises: a three-phase inverter which includes a plurality of switching elements and converts DC current to AC current; a plurality of current detection circuits which detect current flowing through a power line of each phase; a current abnormality detection unit which detects whether an abnormality exists on the basis of the detected current; a failure diagnosis start unit which outputs a failure diagnosis start signal on the basis of the abnormality detection results; an inverter switching command unit which outputs a command which executes a plurality of types of switching patterns for selectively switching a plurality of switching elements so that current flows between the selected two phases; a current analysis unit which analyzes the current detected by the current detection circuit; and a failure location determination unit which determines a faulty location on the basis of the current analysis results and the switching patterns.