Kabushiki Kaisha Toshiba

Junichiro Hagura

Sari Maekawa

Toshimitsu Aizawa

Naoki Oomura

Sadao Ikeda

Shinichi Kominato

A motor control integrated circuit according to embodiments outputs predetermined PWM signals to an inverter circuit that drives a synchronous motor and is configured to perform on-off control on a plurality of three-phase bridge connected switching elements in accordance with the PWM signals to convert direct current into three-phase alternating current, and includes: a PWM generation unit configured to generate the signals based on a received speed command value and output the PWM signals; and a current detection unit configured to detect differential values of phase currents at a predetermined time point that is fixed within a period of a carrier wave used for PWM control, based on the carrier wave and a signal generated by a current detector for detecting current conducted to the synchronous motor, wherein the PWM generation unit calculates a speed of the synchronous motor based on the differential values and then, based on the speed, generates the PWM signals to be applied to the synchronous motor.

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Minato-ku, Japan

Junichiro Hagura