Effects of Load and Speed Variations in a Modified Closed Loop V/F Induction Motor Drive
This paper investigates the eects of load and reference speed variations in a modied closed loopv=f induction motor drive. A modied approach, involving the addition of a low frequency boostvoltage, is developed and adopted as an enhancement to the conventional closed loop v=f speedcontrol of a three phase squirrel cage induction motor modelled in the stationary qd referenceframe using six-step voltage source inverter waveform. The results obtained show a superiordynamic and steady state performance in the two basic mechanical characteristics: motor speedand electromechanical torque under load variation. The performance of this scheme is simulatedin MATLAB/SIMULINK.
Keywords: induction motor, stationary reference frame, Volts/Hertz v=f control, reference speed, load torque