Direct Torque Control Strategies for Permanent Magnet Synchronous Machines

Abstract

In this research, the application of Model Predictive Direct Torque Control (MPDTC) and conventional Direct Torque Control (DTC) techniques to Permanent Magnet Synchronous Machines (PMSMs) is compared. DTC is a prevalent control strategy that directly controls the electromagnetic torque and stator flux by choosing appropriate voltage vectors in response to real-time error signals from hysteresis controllers. For high-performance applications, DTC must be improved since it is vulnerable to torque and flux ripples because it relies on hysteresis controllers and a predetermined switching table. It also has a variable switching frequency which can lead to increased power losses and Electromagnetic interference. Hence, Model Predictive Direct Torque Control (MPDTC) is also researched in this investigation in the hopes of addressing these limitations. By predicting future states of the the machine, it is possible to minimise those ripples.