Denso Corporation

Nagoya Institute of Technology

Jiro Hayashi

Nobuhiko Makino

Makoto Iwasaki

Nobuyuki Matsui

Norio Tsuchida

Takafumi Satou

Yoshifumi Morita

Hiroyuki Ukai

Akihiko Sawada

Yuya Yamamoto

A first inverter circuit and a second inverter circuit are provided for a first winding set and a second winding set of a motor, respectively, and switch over power supply to the winding sets. A control unit controls operations of the inverter circuits. The control unit detects abnormality in the inverter circuits. The control unit calculates a first value with respect to each drive system based on phase currents of the inverter circuit in each system, calculates a second value based on two values selected from a plurality of first values calculated for each drive system, and detects abnormality of the inverter circuits, which corresponds to the selected first value, when the second value deviates from a predetermined range.

Control apparatus for multi-phase rotary machine and electric power steering system using the same

A power transducer failure detection device detects a failure on a power transducer, making a power transducer control device stop driving the power transducer. A first switching control device turns off a first power supply relay of a power supply source switching device and turns on a second power supply relay of the power supply source switching device. While the power transducer stops driving, a motor may rotate due to an external force to generate a regenerative voltage. The regenerative voltage is then regenerated in a battery through a route from the power transducer via the second power supply relay being turned on and a parasitic diode of the first power supply relay. This can protect elements such as switching elements and a smoothing capacitor of the power transducer against a regenerative voltage and prevent the elements from being destroyed or reducing the useful life due to overvoltage.

Motor drive apparatus

There is provided a control apparatus that controls a motor of an electric power steering system to assist a steering effort of an operator. The control apparatus includes a sensor, a parameter computer, a difference computer, a target torque computer, and a motor driver. The parameter computer computes a current value of one of physical parameters of one of constituents of the electric power steering system based on a steering parameter determined by the sensor referring to an equation of motion. The difference computer computes a difference between the current value of the one of the physical parameters computed by the parameter computer and a predetermined value of the one of the physical parameters. The target torque computer computes a target torque of the motor which compensates for the difference between the current value and the predetermined value of the one of the physical parameters.

Control apparatus for electric power steering system

A motor-assisted power steering apparatus includes a DC motor which is fixed to a heat conductive frame, a torque sensor for detecting steering torque and a control circuit for controlling current supplied to the motor. The control circuit includes a first unit disposed in a space defined by the frame and a commutator of the motor and a second unit disposed outside the motor. The first unit includes multiple switching elements connected to the motor, and the second unit includes a microprocessor for setting motor current, a current detecting unit for detecting current supplied to the motor, a current control unit for providing duty ratio signals and a gate driving circuit for driving the switching elements according to the duty ratio signals.

Motor-assisted power steering apparatus

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Jiro Hayashi