Comparative analysis of total harmonic distortion on the current waveform by PWM fed and Vector Controlled Permanent magnet synchronous motors

This paper involves analysis, control and modeling of PMSM and It involves the use of Permanent magnet synchronous motors. It also observes its effects on Total current harmonic distortion by making use of PWM generator and Vector control method . By making use of Park’s transformation ,one can convert three phase system to two phase and then convert it to stationery two axes system (d, q) and finally to synchronously rotating reference frame system By varying both the vectors of flux and torque,(one on quadrature and other on direct axis) one can control the rotor current and therefore, speed of the motor and then THD for current and voltage can be calculated. Adjustable speed drive are becoming a important load component for power distribution Harmonics are lesser in amplitude and more in frequency as compared to the fundamental. Vector control and direct torque control are employed in variable-speed ac drive systems, particularly for induction machine drives. In order to generate PWM signals, an error value is calculated by comparing the current reference and actual current, and it is used as an input for hysteresis control. Then, the voltage vector is obtained, and the motor is driven by using the inverter to follow current reference values