Abstract:
Wound rotor induction motors have been popular for decades in the cement and mining industry for starting and driving large grinding mill. A wound rotor induction motor is large ac motor that controlled starting characteristics and adjustable speed capability. Slip power recovery wound rotor induction motor drives are used in high power, limited speed range applications where control of slip power provides the variable speed drive system. Traditional method of speed control of slip ring induction motor is variable resistance method but losses occurs are more. So, in this paper rotor resistance method and slip power recovery system is used for the speed control of slip-ring induction motor and analysis of speed and power loss is carried out. MATLAB/Simulink is used to simulate this both method for slip-ring induction motor and prove that in rotor resistance method speed control is possible but the system loss is increase whereas in slip power recovery system by change in firing angle of inverter we can change speed of motor and save power which is loss in resistance.

Keywords: Slip power, MATLAB/Simulink, Firing angle, Slip Power Recovery System