25-09-2014, 03:02 PM
Abstracts: In this project we are doing single phase induction motor speed control by using Triac. The complete control circuitry depends on only one parameter i.e, Voltage. We know that torque developed is proportional to square of the voltage. Thus the applied voltage to induction motor stator terminals is controlled by triac and its gate pulses. When pulses to the gate are delayed then reduced voltage is applied to the induction motor stator terminals and thus as voltage and torques are proportional to each other, torque decrease and simultaneously speed of the motor gets reduced. The control circuitry consists of the following. 1. Triggering circuit 2. Triac circuit and 3. Power supply circuit. The power supply circuit will provide DC supply 5v and 12v to the electronic devices which require the biasing voltage.The triggering circuit will generate the pulses and are given to triac as gate pulses for triggering purpose. And finally triac circuit acts as intermediate part between supply and induction motor.