Modelling and Control of an Asynchronous Machine

Asynchronous Machine is the most widely used industrial due to its reliability and high robustness, low cost and good efficiency. Field oriented control technique (FOC) of AC machines facilitates the dynamic control of asynchronous motor. The Field Oriented Control improves the dynamic performance of an induction motor and is commonly used method for speed and torque control applications. In this book, the basic concepts and equivalent circuit model of an asynchronous motor are explained. A mathematical model is developed for squirrel cage induction motor. The three-phase inverter, which supplies desired voltage/current to the stator winding is designed based on Pulse Width Modulation (PWM). The space vector PWM technique is implemented for controlling the three-phase inverter switches, which is simulated using Matlab/Simulink. We present also a modeling of the direct torque control to improve the whole inconvenient by a system with discrete events, which is used to control asynchronous machines. The computer simulations are used to show the efficacy of the proposed algorithm.