Hitachi Automotive Systems, Ltd.

Tomio Sakashita

Mitsuo Sasaki

Toshiyuki Ajima

Tomonobu Koseki

Shigehisa Aoyagi

Masao Fujimoto

Keiji Hamada

Hiroshi Aoyagi

Heat radiation base bodythat is adjacent to electric motor unit EM and extends in direction of rotation shaft of electric motor is provided close to rotation shaft of electric motor. Boardof one electronic control unit of redundant system is fixed to heat radiation base body along direction in which heat radiation base bodyextends with thermal conduction to heat radiation base bodyallowed. Boardof the other electronic control unit of redundant system is fixed to heat radiation base body so as to face to boardof one electronic control unit of redundant system, with thermal conduction to heat radiation base bodyallowed. Rotation position detection circuit boardto which neutral terminalsof electric motor for each phase are connected is provided between heat radiation base bodyand motor housing

Electric drive device and electric power steering device

A motor driving device is operable with low current consumption at low cost and can be started up without delay. The motor driving device includes inverter circuits, relay circuits, power supply stabilizing capacitors, pre-charge circuits, and a control unit. The inverter circuits individually drive coil sets of a motor. Each relay circuit is provided between a power supply and a corresponding one of the inverter circuits. Each capacitor is provided between a corresponding one of the relay circuits and a corresponding one of the inverter circuits. The pre-charge circuits, which are provided corresponding individually to the capacitors, each charge a corresponding one of the capacitors before the relay circuits are driven. The control unit controls the pre-charge circuits so that the pre-charge circuits charge the capacitors at mutually different timings or alternately when failure diagnosis is performed on the relay circuits.

Motor driving device, failure diagnosis method for motor driving device, and electric power steering apparatus using motor driving device

Disclosed is a motor driving device for driving a motor having coil sets that includes energization systems each including a drive circuit, the drive circuits being one-to-one connected to the coil sets; first semiconductor switches disposed in the energization systems in a one-to-one correspondence, each first semiconductor switch lying between a power supply and the corresponding one of the drive circuits; and a second semiconductor switch which connects the power supply and each of the first semiconductor switches in series. Each of the first semiconductor switches includes a parasitic diode of which a forward direction is from the corresponding drive circuit to the second semiconductor switch, and the second semiconductor switch includes a parasitic diode of which a forward direction is from the power supply to the first semiconductor switches.

Motor driving device

An electric motor drive control device includes: an inverter circuit that converts DC power inputted via a DC bus to multiphase AC power and outputs the multiphase AC power to an electric motor; a current detector that detects a DC current flowing in the DC bus; a PWM generator that generates PWM signals and outputs the PWM signals to the inverter circuit; a current calculator that calculates a current value for each of phases to be flowed to the electric motor based upon a value of the DC current and the PWM signals; and a current controller that generates a command signal based upon the current value, and outputs the command signal to the PWM generator, wherein: if one of the phases of the AC power has become missing, the current calculator determines which phase is one that has become missing and calculates current values for other phases.

Electric motor drive control device, electrically driven power steering device, electrically driven brake device, and electrically driven pump device

The present invention provides a motor drive control device provided with a shutoff circuit employing semiconductor relays and configured to drive a motor by a duty ratio control of an inverter, which stably drives the motor even in an operation state that drive duty ratio of phases are uneven. In the motor drive control device, output lines of three phases of the inverter circuit are connected to phases of the motor and further connected to a booster circuit, an output boosted by the booster circuit at a time of drive of the motor is distributed to semiconductor relays connected to respective phases of the motor, and furthermore, a switching circuit for stopping actuation of the booster circuit to shut off drive of the motor, is interposed in a line for supplying an electric power to the booster circuit.

Growing community of inventors

Isesaki, Japan

Tomio Sakashita