Motor control device

Abstract

A motor control device includes a control unit that performs sensorless control of a brushless motor having three phases, and a determination unit that determines presence or absence of step-out of the brushless motor by comparing a deviation hV between a determination voltage Vqj calculated from a rotational speed w of the brushless motor and an estimated q-axis instruction voltage Vqc of the sensorless control with a determination threshold value Hs. The determination unit sets a calculation map Zhs for calculating the determination threshold value Hs to be larger than a characteristic Zes of a first error Es included in the sensorless control in a state in which the brushless motor is not out of step. For example, the determination unit sets the calculation map Zhs such that the determination threshold value Hs is determined to be larger the higher the rotational speed w.

Dependencies are inferred from the claim text.