Denso Corporation

Hiroshi Amano

Tomoyuki Sumi

Koji Sakai

Hideji Yoshida

Yasuaki Aoki

An electric compressor, wherein an inverter device, which controls the operation of an electric motor by commands from an external control unit, is provided with a drive IC which computes drive signals of the electric motor based on the same, a switching circuit which converts the drive signals to rotation control signals of the electric motor, and an output signal control IC which cuts off input of the drive signals to the switching circuit at the time of an abnormality and wherein, furthermore, the drive IC is provided with a comparator which compares drive signals which are input to the switching circuit and computed values of the drive signals at a control unit inside the drive IC and, when the drive signals and the computed values do not match, the comparator makes the output signal control IC cut off input of the drive signals to the switching circuit.

Electric compressor

An inverter circuit for a motor outputs three-phase AC currents, which are outputted from common connection points to stator coils, based on output voltage of a DC power source and a power supply capacitor by a switching operation of transistors. An inverter control circuit determines that a system main relay is turned off, upon receiving a main relay-off signal from an electronic control unit. The inverter control circuit turns on the low-side transistors, while turning off the high-side transistors. A discharge current flows from the positive electrode to the negative electrode of the power supply capacitor through the stator coil and the low-side transistors, so that electric charge stored in the power supply capacitor is discharged.

Driving apparatus for a vehicle-mounted electric motor

An apparatus is provided for controlling a synchronous motor. The apparatus comprises a first calculator calculating a voltage characteristic showing a characteristic of voltages to be applied to armature coils of a stator and a producer producing a command signal to provide the armature coils with the phase currents on the basis of the voltage characteristic. The apparatus still comprises a current detector detecting a signal depending on an amplitude of at least one of the phase currents, a second calculator calculating a rate of changes in a current amount indicating amplitudes of the phase currents, by using the signal from the current detector, and a feed-back member feed-backing the rate of changes in the current amount into the calculation of the voltage characteristic.

Growing community of inventors

Nishio, Japan

Hiroshi Amano