Department of Electrical Engineering and Computer Science
EEL6208 Advanced Electric Machinery
Homework Set No. 3
Problem 15.
Use MatLab symbolic toolbox to derive equations in notes “dq Theory for Synchronous
Machine with Damper”.
Problem 16.
We have studied 3 phase rectifier in class. For a 5 phase rectifier, find the relationship
between phase voltage and output DC voltage.
Confirm your results using SimuLink.
Problem 17.
Using embedded MatLab to build a model for a 200 KW synchronous generator system
which consists of a main machine and an exciter. Assume the generator speed is 12 krpm
(fixed). The DC bus voltage after rectification should be regulated to be 270 V DC
through a controller. After building the model, plot figures like those in my Topic 16b
notes. Neglect damper when you build models. Key parameters are:
For the main machine (10 pole):
Rs  0.008
R f  0.2
Lls  8.5μH
Lmd  90μH
Lmq  40μH
Llf  0.65mH
Lmf  7mH
Lsf  0.6mH
For the exciter (6 pole):
Rs  0.035
R f  0.012
Lls  7.5μH
Lmd  80μH
Lmq  35μH
Llf  10μH
Lmf  0.1mH
Lsf  75μH
Problem 18.
Build Simulink models for the induction machine (without controller) designed in course
example. Estimate inductances. Then connect your model to a 60 Hz, 3 phase, 460 V
(line to line) sinusoidal AC source. Plot abc currents, torque and dq current versus time
until the motor goes to steady state. Compare your dq currents when you use different
reference frames (stationary, rotor and synchronous) in Simulink.
More problems are going to be added.