Phase current estimation device of motor and magnetic pole position estimation device of motor

摘要

A phase current estimation device (10) of a motor (11) includes: an inverter (13) which uses a pulse width modulation signal to sequentially oommutate an electric flow to a motor (11) of a three-phase alternating current; a pulse width modulation signal generation unit (25) generating the pulse width modulation signal from a carrier signal; a control unit (24) performing a startup control and a self control of the motor (11) using the inverter (13); a direct current sensor (31) detecting a direct current of the inverter (13); and a phase current estimation unit (23) estimating a phase current based on the direct current detected by the direct current sensor (31).