Abstract

The main intention of this project is to develop an induction motor speed control system which is helpful to control the speed ofan induction motor using TRIAC. In this project, the zero-crossing point of the voltage waveform is detected by a comparator whose outputis then fed to the microcontroller. And microcontroller also interfaced to Bluetooth it takes signal from the android app. As signal comefrom android app the speed of induction motor will decreases or increases Then, it provides the required delayed triggering pulses to a pairof SCRs through an opto-isolator connected to this circuit. Finally, power is applied to the load through the SCRs. 2 push-button switchesare interfaced to the controller for increasing and decreasing the AC power to the load. In this project, a lamp is used in the place ofinduction motor demonstration purposes. The motor speed variation depends on the power reduction. This project in future can be enhancedby using 2 such units in any 3-phase supply for 3phase induction motor. “Android” the world’s most popular mobile platform which is toolfor creating application that look great and take advantage of hardware capabilities. The advantage of android is that it is an open sourceoperating system is used in terms of mobile application that is smart phone which will act as a remote controller. Here the proposed systemis designed to controlling the speed of induction motor using android application where the remotely controlling speed of induction motoris achieved. Android mobile act as a transmitter and the received by Bluetooth receiver interfaced to AVR microcontroller of 8051 family.AVR is an advanced version of 8051 microcontroller. Each time data is sent by android application as per code written is executed by AVRto deliver supply signal to triac through optical isolation. Hence the power to load connected in series with triac is controlled based onreceived signal and speed control of induction motor is achieved