Vorrichtung zur Steuerung eines elektrischen Motors

摘要

A motor driving apparatus which makes it possible to continue a suppressed power supply to an electric motor even when a detected value (Id) of a current flowing to an H-bridge circuit indicates abnormality, to thereby prevent occurrence of shock in a system in which the motor is employed as a drive source. The apparatus includes a current detecting means (12) for detecting an electric current (I) flowing to an H-bridge circuit (1), and a control means (20) which includes an abnormality decision means (24) for determining abnormality of the detected current value (Id) outputted from the current detecting means (12). When the detected current value (Id) indicates abnormality, both of the ones (Q1; Q4) of the transistors (Q1; Q2 and Q3; Q4) inserted at the side of the power supply source (3) and the ground (GND), respectively, are driven under the PWM control.