ASSIGNMENT # 02 Part B: BEE-15ABC
EE-260 Electrical Machines
CLO1
Submission Date: 5 Oct, 2025
Instructions:
(i)
Please attempt both the questions on paper. Compile your neat work in a single pdf file and
upload on lms
(ii)
Use the following format for the file name.
reg number. complete name (i.e. 380046.Muhammad Bilal Khan)
Q1. A 2-kVA, 240/24-V, 50-Hz single phase transformer was tested in laboratory to determine
its excitation branch components, its series impedances, and its voltage regulation. The
following test data have been taken from the high voltage side of the transformer:
Open-circuit test
Short-circuit test
VOC = 240 V
VSC = 2.5 V
IOC = 0.125 A
ISC = 8 A
POC = 3 W
PSC = 10 W
(a) What are the rated primary and secondary currents of the transformer? [5]
(b) Determine the series and excitation branch impedances of the transformer?[5]
(c) Sketch the equivalent circuit of the transformer referred to the low-voltage side.
Clearly indicate values of the series and excitation branch impedances. [5]
Q2. A 20-KVA, 220/20-V conventional transformer is to be used to supply power from a 240V source to a 220-V load. Considering the transformer to be ideal, do the following:
(a) Sketch the transformer connection that will do the required job. [2]
(b) Find the KVA rating of the transformer in the configuration sketched in (a). [4]
(c) Find the maximum primary and secondary currents under the stated conditions.[4]