Patent ID: 7088067
Filing Date: 2006-08-08
Classification: H02P

Abstract:
1. A motor driving apparatus for driving a multiphase motor by controlling energization to star-connected motor driving coils of multiple phases, the apparatus comprising: a rotor position detector section for obtaining rotor position information by detecting back electromotive voltages induced in a motor driving coil of a non-energized phase; a half bridge circuit group including a pair of high-potential-side driving transistors and low-potential-side driving transistors respectively connected to one side of terminals of the motor driving coils and the other side of the terminals which is a neutral point of the motor driving coils; a torque command signal generator section for generating torque command signals for motor driving in accordance with original torque command signals input from the outside and output signals of the rotor position detector section; a pulse modulation control signal generator section for generating pulse modulation control signals for driving each phase coil in accordance with the command signals generated by the torque command signal generator section; and an energization control section which is supplied with the pulse modulation control signals and controls the energization of the motor driving coils of the multiple phases at a predetermined cycle in accordance with the supplied pulse modulation control signals, wherein the energization control section sets an non-energized period during which only one motor driving coil of the motor driving coils of the multiple phases is set to an non-energized state and the energization control section performs the energization to the neutral point in the non-energized period, so that the motor driving is performed in a manner such that a total of coil currents of the multiple phases is not zero in the non-energized period.