Abstract |
This paper proposes active braking schemes for both low and high power induction machines, without using external braking resistors or bi-directional converters as the front end. By dynamically manipulating losses using deadbeat-direct torque and flux control (DB-DTFC), kinetic energy can be dissipated rapidly within induction motors while maintaining accurate torque control. Loss spatial distribution can also be manipulated for thermal balancing. When scaled to high power induction machines, in which the rated efficiency becomes much higher, it is more challenging to induce equivalent maximum per unit braking torque compared to a low power counterpart. In addition to dynamically varying stator flux linkage, DB-DTFC-based braking method using flux injection is proposed to increase total losses for medium voltage high power drives. |