Question

In: Electrical Engineering

Tests were carried out on a three-phase 220 V, 50 Hz, 4-pole delta-connected induction motor. The...

Tests were carried out on a three-phase 220 V, 50 Hz, 4-pole delta-connected induction motor. The following results were obtained from open circuit (no-load) and short circuit tests.

Open Circuit (no-load) Test

Applied Stator Voltage VLine (V)	Stator Line Current ILine (A)	Total Input Power Pin (W)
240	9.6	536
220	7.2	420
200	5.4	352
180	4.3	304
160	3.5	276
140	3.0	248
120	2.5	224

Short Circuit (locked rotor) Test

Applied Stator Voltage

VLine (V)

Stator Line Current

ILine (A)

Total Input Power

Pin (W)

72

14

674

A dc resistance test indicates that the stator resistance per phase is 1.165 W.

a) Estimate the machine’s friction and windage loss and determine the parameters of the full equivalent circuit of the machine.

Using an appropriate form of the machine equivalent circuit:

b) Calculate the losses in the machine and draw a power flow diagram which illustrates the flow of power through the machine when it runs on-load with a slip of 0.06

c) Determine the starting torque, and also the torque when running with a slip of 0.06.

Expert Solution

Manojponduru answered 1 year ago

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