Predictive torque control of induction motor drive

Abstract

This chapter summarizes the application of Model Predictive Control (MPC) technique to a two-level inverter driven induction motor (IM) drive. There are two types of MPC: continuous control set MPC (CCS-MPC) and finite control set MPC (FCS-MPC). In CCS-MPC, the controller generates a continuous output for a modulator, and the modulator generates the switching signals for the inverter to generate the required voltage. Conversely, in FCS-MPC, the finite number of control actions available in the system - inverter switching states for motor drives - is evaluated against the desired control objectives. The outputs of the controller are discrete and are directly used to switch the power switches on/off in the inverter. The finite-state predictive torque control (FS-PTC) of motor drives is an FCS-MPC strategy. In FS-PTC, torque and stator flux are predicted for the finite number of admissible switching states of a voltage source inverter (VSI). In this study, a two-level VSI (2L-VSI) is considered to produce the necessary voltage vectors. Experimental results illustrate that FS-PTC algorithm yields good performance in terms of torque and flux ripple, stator current THD, robustness against load torque disturbance, step torque response and step speed response.