A three phase 10kW, 1700rpm, 60Hz, four poles, Y connected induction motor has a no-load speed...

A three phase 10kW, 1700rpm, 60Hz, four poles, Y connected induction motor has a no-load speed of 1750rpm. The rotational mechanical losses are constant and equal to 500W. The core losses are constant and equal to 300W. The copper losses in the stator equal to the copper losses in the rotor at full load. If the rotor resistance per phase is 0.25?, calculate the following:
a.The frequency of the induced current in the rotor circuit at full load.
b.The percentage speed regulation of the motor.
c.The efficiency of the motor at full load.
d.The power transferred in the air gap at full load.
e.If the starting torque of the motor is five times the full load torque, calculate the starting currentin the rotor circuit.

Expert Solution

Manojponduru answered 3 years ago

•The rotor impedance at standstill of a three-phase, Y-connected, 208-V, 60Hz, 8-pole, wound-rotor induction motor is...

•The rotor impedance at standstill of a three-phase, Y-connected, 208-V, 60Hz, 8-pole, wound-rotor induction motor is 0.1 + j0.5 Ω/phase. •Determine the breakdown slip, (0.2) the breakdown (maximum) torque, (458.37 Nm) and the power developed by the motor at maximum torque (34.6kW). •What is the starting torque of this motor? (176.3 Nm) •Determine the resistance that must be inserted in series with the rotor circuit so that the starting torque is 50% of the maximum torque. (0.034Ω)

The full load speed of a three-phase four-pole 50Hz, 160kW induction motor is 1,475rpm. The starting...

The full load speed of a three-phase four-pole 50Hz, 160kW induction motor is 1,475rpm. The starting torque is 170%, the yield torque is 280% of the rated torque, and the moment of inertia of the rotor is 2.5kg-m ^ 2. The torque of the load converted to the motor shaft is 800 N-m at full load speed and the moment of inertia is 20 kg-m ^ 2. a) Find the starting time when the load torque is assumed to be...

A 6-pole and three-phase induction motor has synchronous speed of (1000) RPM. a) Find the no-load...

A 6-pole and three-phase induction motor has synchronous speed of (1000) RPM. a) Find the no-load and full-load operating speed of motor for the cases given, 1. 2.5Hz electrical frequency of rotor for no-load condition. 2. 6.3Hz electrical frequency of rotor for full-load condition. b) Find the speed regulation of motor by using parameters found above. c) Determine the electrical frequency of rotor under full-load condition so that speed regulation would be equal to 5%? (Electrical frequency of rotor for...

For full load operation of 60Hz, 380V, 4 pole 30kW induction motor, the speed is 1746rpm,...

For full load operation of 60Hz, 380V, 4 pole 30kW induction motor, the speed is 1746rpm, input current 56.2A power factor 90%. In no load operation, input current 17.3A, power factor 13.5%. In full load operation, assume that the mechanical loss is 25% of the total loss and no other losses. a) Iron loss load efficiency b) Find a rotor copper loss under full load c) Iron loss d) Find a fixed automatic hand under full load e) Find the...

An induction machine has four poles and is powered by two three-phase sources. The first feeds...

An induction machine has four poles and is powered by two three-phase sources. The first feeds the stator at 60 Hz and the second feeds the rotor at 180 Hz. Knowing that the rotor rotates in the same direction as the stator field, we ask: a) Does the machine work as a brake, motor or generator? b) What is the slip value? c) What is the angular speed of the rotating field of the rotor in relation to the stator?...

A three-phase, 11.2-kW, 1750-rpm, 460-V, 60-Hz, four-pole, Y-connected induction motor has the following parameters: Rs =...

A three-phase, 11.2-kW, 1750-rpm, 460-V, 60-Hz, four-pole, Y-connected induction motor has the following parameters: Rs = 0.53 Ω, R’r = 0.38 Ω, Xs = 1.23 Ω, X’r = 1.45 Ω, and Xm = 25.2 Ω. The motor is controlled by varying both the voltage and frequency. The volts/hertz ratio, which corresponds to the rated voltage and rated frequency, is maintained constant. a) Calculate the maximum torque, Tm and the corresponding speed, ꞷm for 60 Hz and 30 Hz. b) Repeat...

An unbalanced three-phase wye-connected and grounded load is connected to a balanced three-phase four-wire source. The...

An unbalanced three-phase wye-connected and grounded load is connected to a balanced three-phase four-wire source. The load impedances are Za = 14+j3 Ω , Zb = 5-j24Ω and Zc =1+j14 Ω and the phase a line voltage has an effective value of 18 Kv: use line-to-neutral voltage of phase A as a reference. Find the line and neutral current, also find the reactive power delivered to load and power factor.

Q3) A three-phase, Y-connected, 220 V, 13 kW, 60 Hz, six-pole induction motor has the following...

Q3) A three-phase, Y-connected, 220 V, 13 kW, 60 Hz, six-pole induction motor has the following parameter values in Ω/phase referred to the stator: R1 = 0.3 Ω. R2' = 0.15 Ω X1 = 0.5 Ω. X2'= 0.21 Ω Xm = 13.25 Ω The total rotational losses are 450 W. The core loss is lumped in with the rotational losses. For a slip of 0.02, and based on approximate equivalent circuit, determine: (i) The rotor speed. (ii) The stator current....

Three balanced three-phase loads are connected in parallel. Load 1 is Y-connected with an impedance of...

Three balanced three-phase loads are connected in parallel. Load 1 is Y-connected with an impedance of 420+300i Ω/ϕ ; load 2 is Δ-connected with an impedance of 2400-1780i Ω/ϕ ; and load 3 is 170.1+2201i kVA . The loads are fed from a distribution line with an impedance of 2+17i Ω/ϕ . The magnitude of the line-to-neutral voltage at the load end of the line is 23√3 kV. Part A: Calculate the total complex power at the sending end of...

A three-phase, 460-V, 60-Hz, six-pole Y-connected induction motor has Rs = 0.32 Ω, R′ r =...

A three-phase, 460-V, 60-Hz, six-pole Y-connected induction motor has Rs = 0.32 Ω, R′ r = 0.18 Ω, Xs = 1.04 Ω, X′ r = 1.6 Ω, and Xm = 18.8 Ω. The no-load loss, Pno load, is negligible. The load torque, which is proportional to speed squared, is 180 N#m at 1180 rpm. If the motor speed is 850 rpm, determine (a) the load torque demand TL; (b) the rotor current I′ r; (c) the stator supply voltage Va;...

Question