In V/F (Voltage/Frequency) control of a 3-phase induction motor, the ratio of voltage to frequency (V/F) is maintained constant to keep the air gap flux constant. If the voltage is increased by a certain percentage, the frequency must also be increased by the same percentage to maintain the constant V/F ratio.
E∝V
Φ ∝ Bmax ∝ V/f
Flux ∝Im
To maintain magnetizing current constant, if frequency is reduced by 10%, then voltage also to be reduced by 10%.
Torque developed by a motor while running at 1000 rpm is 106 N-m and the shaft torque available is 100 N-m. then the iron and mechanical losses in watts are:
Full load speed of a 400V, 50 Hz, three phase induction motor is 960 rpm. What is its full load slip?
A 4 pole, 50 Hz IM operates at 7% slip. The frequency of EMF induced in the rotor will be ________.
The torque developed in the squirrel cage induction motor with auto-starter is ____________.
The efficiency of a 60 Hz, 6-pole, 1000 rpm 3-phase induction motor is ________.
The rotor resistance and reactance of a 4-pole, 50 Hz, 3-phase slip ring induction motor are 0.4 Ω and 4 Ω per phase, respectively. Calculate the speed at maximum torque.
