Hitachi Astemo Ltd.

Kyoshiro Itakura

Daisuke Goto

Toshiyuki Ajima

Kenichiro Matsubara

Takahiro Ito

Makoto Matsuura

Takafumi Hara

Takahiro Araki

A motor control device connected to a power converter that performs power conversion from DC power to AC power and controls driving of an AC motor that is driven by using the AC power includes a voltage command generation unit that generates a three-phase voltage command; and a gate signal generation unit that performs pulse width modulation on the three-phase voltage command and generates a gate signal for controlling an operation of the power converter, in which the voltage command generation unit adjusts the three-phase voltage command by using a zero-phase voltage based on a power factor of the AC power in an overmodulation region in which a modulation factor according to a voltage amplitude ratio between the DC power and the AC power exceeds a predetermined threshold value, and the gate signal generation unit generates the gate signal by performing pulse width modulation on the adjusted three-phase voltage command.

Motor control device, electromechanical integrated unit, boost converter system, electric vehicle system, and motor control method

There are provided a brake control device and a brake control method capable of estimating a rigidity change due to a temperature change, uneven wear of a brake pad, an inclination of a brake disc, or the like with a low memory load and with high accuracy up to a region with larger thrust than a measurement range. A brake control device controls a braking unit including a friction member pushed on a braking target member, a piston that abuts on the friction member and moves in a linear motion direction by rotation of an electric motor, and a thrust detection unit that detects thrust of the friction member to the braking target member. The brake control device estimates a relation between a piston position being rigidity of the braking unit, and the thrust, based on a first piston range that is a thrust change as a first inclination with respect to the piston position, and a second piston range that is a thrust change as a second inclination different from the first inclination, with respect to the piston position.

Brake control device and brake control method

An object of the present invention is to appropriately control a clearance amount by correcting an estimation error of a contact position caused by a delay time difference between output signals of sensors, and to establish both improvement of fuel efficiency due to prevention of drag of a brake pad during non-braking and reduction in response time during braking. A brake system includes a brake disc, a brake pad, a piston, a drive mechanism, a position sensor that detects a position of the piston, a thrust sensor that detects a thrust by which the brake pad presses the brake disc, and a brake control unit that adjusts a braking force by controlling the drive mechanism. The brake control unit includes a contact position computation unit that computes a contact position at which the brake pad and the brake disc come in contact with each other based on output signals of the position sensor and the thrust sensor, a position error computation unit that computes a position error of the contact position based on a delay time difference between the output signals of the position sensor and the thrust sensor, and a contact position correction unit that corrects the contact position obtained by the contact position computation unit by using the position error.

Brake system

An object of the present invention is to provide a brake control device and a brake system capable of braking with a shortened braking response when shifting from non-braking to braking. A brake control deviceincludes a command value calculation unitthat calculates an operation command value required to make a pressing force by which a brake padis pressed against a brake discreach a target thrust value. The command value calculation unitincludes: a clearance command calculation unitthat calculates a command value required for contact between the brake padand the brake disc; and a thrust command calculation unitthat calculates a command value required for reaching the target thrust from a state where the brake padand the brake discare in contact with each other. When calculating the operation command value from a state where the brake padand the brake discare separated, the command value calculation unitcalculates the operation command value by integrating the command value calculated from the clearance command calculation unitand the command value calculated from the thrust command calculation unit

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Tokyo, Japan

Kyoshiro Itakura