Patent ID: 8988029
Filing Date: 2015-03-24
Classification: H02P

Abstract:
1. A motor driving device comprising: an AC/DC converter that converts alternating current power, which is supplied from an alternating current power supply, into direct current power; a motor driving unit that operates based on the direct current power supplied from the AC/DC converter and outputs a driving signal to a motor; and a start-up auxiliary circuit that is arranged on a path connecting the AC/DC converter and the motor driving unit, wherein the start-up auxiliary circuit: delays an output of the driving signal from the motor driving unit for a first predetermined time period after the supply of the alternating current power from the alternating current power supply to the AC/DC converter starts; and gradually increases a driving voltage of the motor driving unit so that current flowing in a driving coil of the motor is limited to a predetermined value or smaller for a second predetermined time period after the output of the driving signal from the motor driving unit starts; and wherein the start-up auxiliary circuit comprises: a start-up delay circuit that delays the output of the driving signal from the motor driving unit for the first predetermined time period; and a current limiting circuit that limits the current flowing in the driving coil of the motor for the second predetermined time period, wherein the start-up delay circuit comprises: a delay time setting circuit that sets the first predetermined time period; and a switch circuit that sets the direct current power to be supplied from the AC/DC converter to the motor driving unit after the first predetermined time period set by the delay time setting circuit elapses, and wherein the current limiting circuit comprises: a current detection circuit that detects a current value of the direct current power; and an over-current feedback circuit that controls an operation of the switch circuit in response to the current value detected by the current detection circuit.