Patent ID: 6525497
Filing Date: 2003-02-25
Classification: H02P

Abstract:
A phase distortion compensating apparatus for reducing a torque ripple in a 3-phase motor, comprising:a rectifier unit for rectifying an input AC voltage into a DC voltage; upper and lower DC link capacitors connected in parallel to the rectifier unit, each of the DC link capacitors serving to conduct charge and discharge operations for the DC voltage; an inverter connected in parallel to the capacitors and adapted to generate a 3-phase voltage adapted to rotate the 3-phase motor, based on voltages respectively discharged from the capacitors along with a switching signal, and a voltage command generator for calculating compensation components for respective switching operations of switching elements included in the inverter, which are connected to A and B phases of the motor, based on a voltage difference between the capacitors, a difference between an actual rotating speed of the motor and a command speed, and a rotor position of the motor, and providing respective switching times including the calculated compensation components, thereby controlling a rotating speed of the motor, wherein an operational one phase of the 3-phase motor is connected to a connection node between the upper and lower DC link capacitors.