A 250 W, 120 V, 60 Hz capacitor-start single-phase induction motor has the following constants for the main and auxiliary windings at starting:
ZM = 4.5 + j 4.7 ohm, ZA = 3.8 + j 3.6 ohm.
i-What are the values of the added capacitor and resistance such that the main and auxiliary currents at starting are equal and shifted by 90 degree?
ii-What is the ratio of the starting torque with the added components to that without them?

The
problem has been solved by using approximate circuit. The answer
provided is close to exact solution
A 250 W, 120 V, 60 Hz capacitor-start single-phase induction motor has the following constants for...
Q3. A single-phase, 120 V, 60 Hz, four-pole, split-phase induction motor has the following equivalent circuit parameters: Stator parameters: The Main winding (R =1.512, X=2.522), and the auxiliary winding (R=2.512, X=2.52), Rotor parameters referred to the stator side: (R=1N, X=1.592). The magnetizing reactance is equal to 4082. (a)Determine the standstill impedances of both windings. (b)Determine the starting torque and the starting current of the motor if it is started from rated voltage mains as a split phase induction motor. (c)Determine...
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a four pole 60-Hz, 440-V three phase induction motor is supplied by a variable voltage variable frequency source. the motor has negible stator resistance and a rotor resistance of 0.1 ohm. the total inductance is 2 x 10 ^-3 H. a)find lowest possible frequency and voltage of proper operation. b) determine the starting torque, the speed at maximum torque, and the router's applied voltage when supply frequency is 8 hz, 40 hz and 60 hz
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1. A 15 hp, 4 pole, 208 V, 60 Hz, Y-connected, three-phase squirrel cage induction motor has the following parameters in Ω/phase referred to the stator: R,-0.220, Xi = 0.430, X,-15.0, R2 0.130 and X2-0.430. Mechanical and core losses amount to 300 W and 200 W respectively for rated voltage. (a) The motor is fed with a 60 Hz, 208 V voltage. It runs with a slip of 4.5 %. Find the speed, shaft torque and power, efficiency and power...
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A three-phase, 2.2 kV, 60 Hz,
Y-connected induction motor has the following parameters: R1 = 0.2
Ω R2` = 0.4 Ω X1 + X2` = 1.5 Ω The motor’s full load speed is 580
rpm. Ignore the rotational losses and calculate: a. Full load
torque b. Output power rating c. Starting current d. Starting
torque
No poles were provided
A three-phase, 2.2 kV, 60 Hz, Y-connected induction motor has the following parameters: The motor's full load speed is 580 rpm....
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