DRIVE SYSTEM FOR PERMANENT-MAGNET SYNCHRONOUS MOTOR AND TEST METHOD THEREFOR

摘要

PPROBLEM TO BE SOLVED: To prevent increase in the leakage current of a PM motor in a drive system which operates the PM motor at variable speed by an inverter. PSOLUTION: In the drive system which operates the PM motor 1 at variable speed by the inverter 4, when the inductance measured between a terminal in any one phase of the three-phase terminals of the PM motor 1 and ground and earth capacitance resonate with each other, the motor capacitance is increased, resulting in increase of the leakage. To cope with this, the resonance frequency of the PM motor 1 and the carrier frequency of the inverter 4 are staggered. For example, the resonance frequency is controlled to a value 2SP1/2/SPtimes or more the carrier frequency. As a result, the occurrence of resonance is prevented. Thus, increase in the motor capacitance is prevented, and increase in the leakage current is suppressed. PCOPYRIGHT: (C)2003,JPO