Bahçeşehir University
Faculty of Engineering
Name & Surname:
Electrical and Electronics Engineering Department
ID:
Electromechanical Energy Conversion Laboratory
Date:
Experiment 1
Single-phase Transformer
PRELIMINARY STUDIES
In this section you should read your lecture notes and answer following questions before coming to the laboratory. There
may be a quiz concerning these questions.
Q1.List types of transformers and explain where they are used in one sentence.
Q2.Draw a simple electrical equivalent circuit for single-phase transformer.
Q3. What is the relation between inductance and reactance, how do we calculate them?
Q4.What is the turns ratio and how do we use it?
a)Write ratio of voltages
b)Write ratio of currents
c)Write ratio of resistances
d)Write ratio of inductances
e)Write ratio of reactances
Prepared by F.Kemal BAYAT
Page 1 of 4
Bahçeşehir University
Faculty of Engineering
Electrical and Electronics Engineering Department
Electromechanical Energy Conversion Laboratory
EXPERIMENT
Part.1.Identification of Turns Ratios
In this section you are supposed to observe turns ratios of single-phase transformer and autotransformer by using two
voltmeters; one for measuring primary voltage and other one for measuring secondary voltage.
Q5.Define the real and approximate turns ratios of the single-phase transformer.
Q6.Define the operation range of autotransformer.
Part.2.DC Test
Using digital multimeter, measure resistances of the single transformer and record your readings below.
R1
R2a
R2b
=
=
=
___________________
___________________
___________________
Part.3.Open-Circuit Test
With the help of the given circuit diagram below, connect single-phase AC supply to the primary side (0-220V) of the
transformer using an ammeter, a voltmeter, and a wattmeter. Record your readings below :
Voc
Ioc
Poc
=
=
=
___________________
___________________
___________________
Q7.Using the formulas given below calculate following parameters.
Prepared by F.Kemal BAYAT
Page 2 of 4
Bahçeşehir University
Faculty of Engineering
Electrical and Electronics Engineering Department
Electromechanical Energy Conversion Laboratory
Rc
Xm
=
=
___________________
___________________
Part.4.Short-Circuit Test
In this test, you should use autotransformer as the single phase power supply. Remaining connections are identical with
the previous test. Short-circuit test requires a bit more attention, thus wait for laboratory instructor to check your
connections. Record your readings below :
Vsc
Isc
Psc
=
=
=
___________________
___________________
___________________
Q8.Using the formulas given below calculate following parameters.
Zeq
= ___________________
Req
= ___________________
Xeq
= ___________________
X1 = X2 = Xeq / 2 = ____________
Q9.Draw the electrical equivalent circuit referred to primary side (the side that you have done the measurements) and
write resistance and reactance values on the diagram.
Q10.Draw two-sided electrical equivalent circuit and write resistance and reactance values on the diagram.
Prepared by F.Kemal BAYAT
Page 3 of 4
Bahçeşehir University
Faculty of Engineering
Electrical and Electronics Engineering Department
Electromechanical Energy Conversion Laboratory
Q11.Draw the electrical equivalent circuit referred to secondary side and write resistance and reactance values on the
diagram.
Part.5.Simulation
In this part you are to repeat open and short circuit tests in Simulink. The simulation configuration is given in the figure
below. Do not forget to enter the parameters that you determined and used in Q9.
Q12.Compare your measurement results with simulation results. Do they coincide?
Prepared by F.Kemal BAYAT
Page 4 of 4