POWER CONVERTER CONTROLLING APPARATUS AND METHOD PROVIDING RIDE THROUGH CAPABILITY DURING POWER INTERRUPTION IN A MOTOR DRIVE SYSTEM

摘要

A method of controlling a power converter ( 20 ) of a motor drive system ( 10 )controls the power converter ( 20 ) during a first operating mode by applying a current control scheme, which sets power converter commands to control torque current flowing from the power converter ( 20 ) to the motor ( 30 ) to achieve desired motor speed; and initiates a second operating mode when power supply to the power converter ( 20 ) is interrupted. The second operating mode includes controlling negative torque current between the power converter ( 20 ) and the motor ( 30 ) so that mechanical energy from the motor ( 30 ) charges an element ( 58 ) on a power supply side of the power converter ( 20 ). The first operating mode is resumed when the input power recovers. Torque current between the power converter ( 20 ) and the motor ( 30 ) is also controlled to limit a maximum transient DC bus voltage.