| 摘要 |
PROBLEM TO BE SOLVED: To allow noise to be suppressed while sufficiently securing an SN ratio of magnetic pole position estimation.SOLUTION: A magnetic pole position estimation device of a motor includes: current detectors 11a, 11b and 11c being connected to a motor 7 driven by an inverter section 9 converting a DC into a three-phase AC in accordance with a PWM signal pattern and detecting a current value of each phase; a PWM generating section 8 generating the PWM signal pattern shifted with a generation phase of a pulse of a three-phase PWM signal such that a high-frequency current amplitude of each phase of the motor 7 is generated; a phase current detection section 12 obtaining a difference value between twice detection values in each voltage vector period on the basis of a detection value of a phase current detected by the current detectors 11a, 11b and 11c for each phase twice in two kinds of voltage vector periods in a carrier period of the PWM signal pattern; and a magnetic pole position estimation section 5 estimating a magnetic pole position of the motor 7 on the basis of the difference value in three phases or two phases obtained by the phase current detection section 12. |
