National Conference on Innovative Trends in Science and Engineering (NC-ITSE'16) ISSN: 2321-8169 Volume: 4 Issue: 7 29 - 31 ______________________________________________________________________________________ 29 IJRITCC | July 2016, Available @ http://www.ijritcc.org (Conference Issue) _______________________________________________________________________________________ Speed Control of Induction Motor by using V/F Control Method in Matlab Simulink Prof. Piyush. S. Dorale Department of Electrical Engineering, MGICOET Shegaon. piyush.dorale@gmail.com Mr. Mohammad. Zubair Student M.E (EPS) MGICOET Shegaon. muhd.zubair2016@gmail.com Prof. Kavishwar. K. Rajput Department of Electrical Engineering, MGICOET Shegaon. kkrajput2702@gmail.com Prof. Vaibhav. A. Ghodeswar Department of Electrical Engineering. MGICOET Shegaon. ghodeswarvaibhav@gmail.com Prof. Aishwarya. S. Kakad Department of Electrical Engineering, MGICOET Shegaon. aishkakad@gmail.com Abstract— As the power supply which is available at the utility side is mostly AC supply. Therefore, the motors used in industries and in domestic appliances are Induction Motors. Hence researchers are attracted towards the speed control issues of Induction Motor. The speed control method of Induction Motor includes the variable stator voltage, variation in supply frequency, vector control, slip recovery and V/F control method. In this paper we are focusing only on the V/F control method, in this method we are maintaining the V/F ratio constant. The electrical areas which are mostly required to control Induction Motor are Control, Power Electronics, and Electrical Machines. Thus, by using Power Electronics devices such as MOSFET’s or IGBT’s we can easily control the speed of Induction Motor. This technique of speed control we are going to represent with help of MATLAB Simulation. Keywords- SVPWM, VSI, V/F & Induction motor. __________________________________________________*****_________________________________________________ I. INTRODUCTION Electrical Energy has the contribution more than 40 % of all energy sources usage on Earth. In the upcoming years the percentage contribution of Electrical Energy will be increase. More utilization of Electrical Energy is to convert the Electrical Energy into Mechanical Energy via different kinds of electric motors like DC Motors, Induction Motors and Synchronous Motors. From the economic point of view Induction Motor are cheap compared to DC and Synchronous Motors. Induction Motors are most popular and widely used drives in industries as well as for domestic applications. It is very important to control the speed of induction motors in industrial and domestic applications. Speed control techniques of induction motors can be broadly classified into two types – scalar control and vector control. By using scalar control method we can control the magnitude of voltage or frequency of the induction motor. To maintain torque of the motor closer to the rated torque at any frequency, the air gap flux, φag is maintained constant. Any change in the supply frequency i.e. reduction in supply frequency without changing the supply voltage will increase the air gap flux and the motor may go to saturation. This will increase the magnetizing current and increases the core losses and copper losses, due to which system becomes noisy. So to avoid these problems we are changing the supply voltage as well as supply frequency [3]. II. CONVENTIONAL METHODS OF SPEED CONTROL 1. Pole Changing 2. Variable Supply Frequency Control 3. Variable Supply Voltage Control 4. Variable Rotor Resistance Control 5. V/f Control 6. Slip Recovery 7. Vector Control III. SELECTION OF V/F CONTROL METHOD V/f Control method is mostly used rather than the other conventional methods of speed control, due to its ease of implementation and having various advantages as given below- 1. It provides wide range of speed. 2. It has low starting current requirement. 3. The acceleration can be controlled by controlling the rate of Change of supply frequency. 4. It is economical and easy to implement. 5. It gives good running and transient performance. 6. Voltage and frequencies reach rated values at base speed. IV. SPEED CONTROL USING ELECTRONICS DEVICES As we are using electronics devices for the speed control of Induction Motor first we have to convert the ac supply into dc supply by using rectifier and then fed to the inverter via the DC bus filter. Inverter circuit is having switching devices such as MOSFET or IGBT. The output of inverter is connected to the Induction Motor whose speed is to be control as shown in the figure 1. The DC bus filter is used to take out the ripples from the dc supply which is coming out from the rectifier [1].