DAVID S COLSON
Radio and Television Technicians in Wakefield, MA
License number
Massachusetts 52793
Expiration Date
Dec 31, 2014
Type
Registered Technician
Address
Address
Wakefield, MA 01880
Professional information
Dynamic Braking For Electric Motors
US Patent:
8154228, Apr 10, 2012
Filed:
Jun 10, 2009
Appl. No.:
12/481925
Inventors:
George B. Yundt - Andover MA, US
David S. Colson - Wakefield MA, US
David S. Colson - Wakefield MA, US
Assignee:
Kollmorgen Corporation - Radford VA
International Classification:
H02P 3/00
US Classification:
318375, 318432
Abstract:
A system and method are provided for improved dynamic braking in AC motors with an electronic drive, and more particularly to using a current regulation circuit to control the current supplied to the motor to be in phase with the internal EMF voltage of the motor such that the braking torque of the current is maximized per ampere of dynamic braking current when needed to stop the motor in case of a control failure or emergency. A current regulator produces a voltage command to the motor based on the current command input. The motor is still controlled by a d-q current regulator and the q-axis (torque axis) voltage is driven to zero while the d-axis (non-torque axis) is left in current control with a zero current command. This way the motor internal voltage drives a current in the terminals of the motor but the current is in phase with the internal voltage of the motor. Since the current loops are still active, current limiting may be implemented and the dynamic brake current amplitude can be well controlled and entirely goes into stopping the motor.