Deadbeat Direct Torque and Flux Control (DB-DTFC) Algorithm Evaluation and Optimization for Automotive Traction Applications

Abstract

This research project studies the application of Deadbeat Direct Torque and Flux Control (DB-DTFC) for its implementation with Interior Permanent Magnet Synchronous Machines (IPMSMs) in traction applications. DB-DTFC is a discrete control method that can achieve the desired torque and flux commands in one sampling instant. The voltage command generation process and the controller nature have great potential for providing a more efficient and effective control strategy particularly around the voltage limit and for high speed operation First, the state of the art was considered and the operation of DB-DTFC in the MTPA and MTPF regions was studied. Particularly, the Square Root Condition (SRC) method applied to the DB-DTFC algorithm was proven to be a viable MTPF strategy with better performance than classic Current Vector Control (CVC) approaches. Second, the capabilities of the already implemented systems presented. For the development of this project a testbench was available that provided opportunities for better analysis of the behaviour of the drive. Finally, the concept of overmodulation is studied for its application to DB-DTFC. Multiple reference adaptation methods were tested, as well as classic Direct Torque Control (DTC) strategies and a new algorithm for six-step voltage selection emerging from the DB-DTFC insights was introduced.