Design and implementation of a minimum-time torque control for IPM motor drives

Emerging applications, like electrical test benches for automotive, require extremely fast large-signal torque responses. Conventional, low-complexity PID-Iike controllers are inadequate for the task, especially when associated to internal permanent magnet (IPM) synchronous motor drives. Conversely, as shown in this paper, time optimal control (TOC) assures the fastest torque response after any large demanded variation of the torque reference. The innovative technique self-recognises the best final state, for given starting point and desired torque level. The paper reports the mathematical and algorithm details, as well as a complete batch of comparative measurements, carried out on a working prototype.