Performance and Analysis of Direct Torque Control of Permanent Magnet Synchronous Motor

Direct torque control (DTC) is a method to control machine with utilizing torque and flux of motor controlled. In recent years Permanent Magnet synchronous motors (PMSMs) are used in many applications that require rapid torque response and high-performance operation. PMSM has no damper windings and excitation is provided by a permanent magnet instead of a field winding. The elimination of field coil, dc supply and slip rings reduce the motor loss and complexity. It is mathematically proven that the increase of electromagnetic torque in a permanent magnet motor is proportional to the increase of the angle between the stator and rotor flux linkages, and, therefore, the fast torque response can be obtained by adjusting the rotating speed of the stator flux linkage as fast as possible. This is achieved by using direct torque control (DTC) technique and results are analyzed under three different conditions. This paper presents the MATLAB/SIMULINK-based simulation model by adopting the classical double closed loops of speed, current and vector control method and introduces the principle of space vector pulse width modulation (SVPWM) ,and closed loop speed control technique namely Direct Torque Control for Permanent Magnet Synchronous Motor Drive.