Sinusoidal Pulse Width Modulation for Speed Regulation of a Three-Phase Induction Motor under Load

Adjustable industrial speed drives require closed-loop speed control. Three-phase voltage source inverters (VSI) need adjustable voltage and frequency. Sinusoidal pulse width modulation (SPWM) is used to regulate the speed of an induction motor (IM) powered by a three-phase VSI. PI controllers reduce steady-state speed inaccuracies. In MATLAB-Simulink, the performance of the closed-loop speed control system is evaluated. The motor's speed decreases as the load torque increases, but it quickly recovers with minimal undershoot during a short settling time. Simulations demonstrate that the speed controller has enhanced dynamic response, allowing it to adjust the induction motor's speed and torque. The simple, costeffective Volts/Hertz (v/f) control method for a three-phase induction motor is widely used; however, its dynamic performance is limited. A closed-loop system with an appropriate controller effectively regulates speed. An accurate mathematical model of the system is essential for the Proportional-Integral (PI) controller, which is commonly employed. Therefore, a robust controller may impact the simplicity of the v/f control system.