The Ideal Transformer

Jesus M. Martinez, Jr, Mapua University, School of Electrical, Electronics, and Computer Engineering
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Summary

This teaching activity shows how to input phasor values (voltage, current, impedance, power) as demonstrated in an ideal transformer model. It shows how to perform voltage, current, and power calculations. The activity also shows how to plot the instantaneous values (voltage, current and power), phasor diagrams (voltage and current, impedance diagram, and power diagram.


Learning Goals

After performing this activity, students should be able to:
(1) Plot the instantaneous values of ac voltage, current and power.
(2) Plot the phasor diagram of ac voltage and current.
(3) Plot the impedance diagram of a transformer load.
(4) Plot the real power, reactive power, and apparent power.
(5) Label plots using LaTeX typeset.
(6) Perform circuit calculations on an ideal transformer model.

Context for Use

This is a classroom activity for undergraduate electrical engineering students taking up a course in ac transformer.

This activity can be performed in one period (1 hour) during or after discussing transformer basic principles.

The activity (easy) requires basic knowledge of inputting complex number in Matlab, performing complex arithmetic operations, plotting. Some basic knowledge of LaTeX typesetting is also needed.

Students must have a basic knowledge of complex number arithmetic, basic circuit and ac transformer principles before performing this activity.

Description and Teaching Materials

Please download the required materials as shown below. Follow the instructions provided in the file IdealTransformerTemplate.docx

(1) idealtransformer.mlx - This Live Script file contains the discussion and codes needed in performing this activity.

(2) phasorarrow.m - This user defined Matlab function will be needed in plotting the phasor diagram.

(3) IdealTransformerTemplate.docx - This is the datasheet template for this activity.


Matlab Live Script for The Ideal Transformer activity (MATLAB Live Script 2.4MB Dec1 21)
User-Defined Matlab function for Plotting a phasor (Matlab File 1kB Dec1 21)
Ideal Transformer Datasheet Template (Microsoft Word 2007 (.docx) 621kB Dec1 21)

Teaching Notes and Tips

The teacher should first discuss how to create Matlab Live Script and what type of data can be included in the Live Script file. Next, the teacher should also discuss the supplementary user-defined function phasorarrow.m and how it can be used to plot the phasor diagram. Finally, the teacher should also have a separate discussion on LaTeX typesetting in Matlab.

Assessment

Points will be given separately for the table and figure (results and plotting commands).
The tables of results will be graded based on its completeness and correctness of data.
Figures will be graded based the correctness of the commands used and the resulting figure.
Aside from the datasheet submission, students will also be graded based on his/her submission of the edited Live Script file.

Students must reach or exceed the minimum passing score to pass this activity.

References and Resources

(1) Transformer Wikipedia Page - https://en.wikipedia.org/wiki/Transformer

(2) Writing Mathematical Equations in LaTeX - https://www.docx2latex.com/tutorials/Mathematical-equations-LaTeX.html/