Comparison between direct torque control and vector control of a permanent magnet synchronous motor drive

This paper presents a comprehensive comparison between two speed control techniques for permanent magnet synchronous machine using vector control (VC) and direct torque control (DTC). The main characteristics of vector control and direct torque control are studied by simulation emphasizing their advantages and disadvantages. The performances of the two control techniques are evaluated in terms of torque and current ripples, and transient responses to load toque variation. The simulation results show that the two control schemes provide in their basic configuration, comparable performances regarding the torque control, however the choice for the DTC appears advantageous in many respects, and presents a low cost solution for applications where low torque ripple is not a major issue.