Comparison of regenerative braking controllers for permanent magnet synchronous machines

Since most electric machine applications involve accelerating and decelerating mechanical loads, there is a potential to recover stored kinetic energy during braking events. However, this potential cannot be fully realized without proper design of the braking controller, since electric machine braking may be either regenerative or non-regenerative. This paper develops a novel method for designing regenerative braking controllers for permanent-magnet synchronous machines, based on the concept of using speed feedback to apply a fraction of the electromagnetically induced voltage at the machine terminals.