Transformer and Induction Motor Tests and Analysis

Chapter 3.2
a)
The foloowing data has given.
OPEN CIRCUIT VOLTGE 11000V, 70W, 21.8Ma
SHORT CIRCUIT VOLTAGE 310V, 80W, 0.9A
Determine the power factor.
Determine the magnetization current.
Determine the watt full component current.
Determine the shunt branch parameter.
SHORT CICRCUIT CALCULATION:
Determine the series parameter of transformer.
The equivalent circuit diagram has shown in figure 3-2.

b)
The phasor diagram for transformer has shown in below figure 3-2b.
Determine the primary rated current.
Determine the voltage required to apply to primary winding when transformer supply.
c)
Determine the regulation of the transformer when supply rated KVA at 0.8 pf lagging.
Chapter-4
a)
The following were taking during open circuit test and short circuit test on a three phase,
10MVA, 13.8 Kv, 50Hz synchronous genrator driven at rated speed.
OPEN CICUIT TEST
Field Current 150A 180A 200A 250A 300A 350A
Line voltage 11.2kv 12.0kv 12.5kv 13.5kv 14.3kv 14.8kv
SHORT CIRCUIT TEST
Field Current 150A 180A
Short Circuit Current 400A 480A
Determine the following open circuit and short cicuit characteristics on the same graph
has shown in figure 1.
Determine the saturated synchronous ractance of the genrator.

b)
Determine the exitation voltage E and Load angle at rated KVA and 0.8 pf lagging.
GIVEN DATA:
Calculate excitation E.
C)
If field excitation is reduce to 80% the load torque angle should not increase more than
, therefore alternator become unstable, if current reduce more than rated flux, hence
alternator unstable, because power real power is unchanged(constant).
Chapter 5
The three phase induction motor 220v, 50hz, 4 pole delta connected. The following
results were obtained from open circuit (no load) and short circuit.
Applied Stator voltage stator Line current Total input power
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
The short circuit data:
Applied Stator voltage Stator Line current total input power
72 14 674
a)
Determine the machine friction and windage loss.
Determine shunt parameter of induction motor.
Determine power factor.

Determine the watt full comment of induction motor.
Determine the magnetization current of induction motor.
Determine R01and X01
BLOCKED ROTOR TEST
Determine series parameter of the induction motor.
The equivalent circuit of the machine has shown figure 5-a.