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.