Vector control of voltage source inverter fed induction motor drive using space vector PWM technique

Induction motors are widely used in industrial applications due to their relatively low cost, high reliability and almost free maintenance. It is rugged, lower cost and weight, reliable and almost free maintenance when compared to DC motor. There are a number of ways of controlling induction motors. Among these, V/f control is the most traditional method. As induction motor requires a coordinated control of stator current magnitude, frequency and phase, which is not possible in V/f control of induction motor drives, this method gives a low dynamic performance. Vector control, also known as Field-Oriented Control (FOC) is an alternative. Vector control involves decoupled control of flux and torque. This is achieved through the four control loops which are controlled using PI controllers. PI controllers under saturation give delayed response. This can be overcome by implementing an Anti-windup PI controller, which keeps track of the output under saturation. IGBT based Voltage Source Inverter (VSI) feeds the Induction Motor Drive. Space Vector PWM (SVPWM) technique is used for generating gating pulses. Vector control is a popular control method, but the design seems to be a complicated task. The paper aims at a detailed design of vector control in a simple manner.