Speed control of asynchronous motor by different methods

This study, speed control was made by using different methods of three-phase asynchronous motor with different models. Asynchronous motor control are performed by Voltage/frequency (V/f) constant ratio and Field Orientation method. Advantages and disadvantages was demonstrated by comparison of these two methods. In this study, Matlab/ Simulink program was preferred. Frequency, voltage and rotor rotation speed graphs were examined in V/f constant ratio control method and field orientation control method. Deviation amounts are discussed and the effect of the methods are discussed. According to the results obtained from both control methods discussed in this study, Field Orientation Method are more sensitive control method than V/f constant ratio method for asynchronous motors. The main reason for this result is continuous correction of frequency and voltage with feedback PI control system and the rapid elimination of the error in the Field Orientation method. However, as the Field Orientation method is very complex and difficult to apply to asynchronous motors, therefore the most widely used control method in the industry is the V/f constant ratio control method.