Patent ID: 8324850
Filing Date: 2012-12-04
Classification: H02P

Abstract:
1. A motor driver comprising: an energizing unit including a plurality of switching elements and supplying a drive voltage and a drive current to a motor including a moving body and a three-phase coil, such that the motor is driven by the drive voltage and the drive current; a speed-position detector detecting a drive speed of the motor and detecting a position of the moving body of the motor, so as to output a speed-position signal including drive-speed information corresponding to the drive speed and position information corresponding to the position of the moving body; a reference signal generator outputting a reference signal as a reference for the drive speed; a phase signal generator outputting a phase signal indicating a phase of the drive voltage supplied to the three-phase coil of the motor, the phase signal being output based on the speed-position signal output by the speed-position detector, the reference signal output by the reference signal generator, and a set signal indicating an optional value; and a waveforms generator using the position information included in the speed-position signal output by the speed-position detector and the phase signal output by the phase signal generator to output a control signal to the switching elements of the energizing unit, wherein the phase signal corresponds to a phase difference between a phase indicated by the position information of the speed-position signal and the phase of the drive voltage, wherein the phase signal generator generates a first phase signal in proportion to the drive speed, generates a second phase signal by proportioning the first phase signal with a value of the set signal, and outputs the second phase signal as the phase signal indicating the phase of the drive voltage, wherein the value of the set signal is set in correspondence with the specification of the motor, such that the motor achieves a highest efficiency, and wherein the drive voltage is supplied to the three-phase coil, such that the phase of the drive voltage is proportional to the drive speed in a degree of proportion matching the specification of the motor.