Predictive Control Operating at Fixed Switching Frequency of an Induction Machine Fed by a Voltage Source Inverter

Predictive torque control (PTC) has been established as one of the viable solutions for variable-speed motor drive control, particularly where a fast response for torque and flux control is required. The main reason for its adoption is the exible architecture and good performance attained with a predictive control scheme. One of the main issues with this approach is the variable switching frequency. Therefore this paper presents an implementation of PTC to overcome this issue. The method consists on the application of two active plus zero voltage vectors to generate a fixed number of switching commutations in the inverter legs during each sampling period. The dwell time for each of the voltage vectors are calculated in the optimization process of the predictive control. The scheme is validated simulation results, demonstrating the constant switching frequency operation whilst keeping the high dynamic torque and ux response.