8/8/2019 ENEE 474 Fall 2010 Homeworks

http://slidepdf.com/reader/full/enee-474-fall-2010-homeworks 1/4

ENEE474 Fall 2010 Homework 

ENEE 474 Page 1

Due: October 19th

(at the beginning of class)

For all problems, please provide relevant explanations of your work and show all steps. Just providing

the answer will get you no credit for the problem.

1)  What is the general structure of Power Systems? Please provide a complete overview.

2)  Derive from the terminal relationships [ , ,

] the phasor

relationships [ , , ].

3)  Draw phasor diagrams and provide explanations for the following circuits:

a ) b )

4)  Use the phasor diagram to derive the equation:  

5)  Prove the following:

a)  

b)  

6)  There are four unmarked wires: 3 phases and 1 neutral. Using a voltmeter and makingonly two measurements, describe how you would determine which one of the four wires

is the neutral wire. Please provide both a diagram and a complete explanation.

7)  Shown in the figure below is a Delta-Delta connection.

Given: Find:  

Please show all steps and provide relevant explanations.

C

L R

C1 

LR

C2 

 

b’

   

a’

c’

Z’a 

Z’b 

Z’c   

 

 

Zcb 

ZbaZac

a

bc

8/8/2019 ENEE 474 Fall 2010 Homeworks

http://slidepdf.com/reader/full/enee-474-fall-2010-homeworks 2/4

ENEE474 Fall 2010 Homework 

ENEE 474 Page 2

8)  Prove that p(t) - instantaneous power is constant for balanced load.

9)  Analyze the circuit below. Show all 4 steps and provide relevant explanations.

10) Analyze the circuit below. Show all 4 steps and provide relevant explanations.

11) Prove that  

12) Prove that and  

13) Prove that  

14) Prove that  , where   

O’ 

O 

’

a’

b’

8/8/2019 ENEE 474 Fall 2010 Homeworks

http://slidepdf.com/reader/full/enee-474-fall-2010-homeworks 3/4

ENEE474 Fall 2010 Homework 

ENEE 474 Page 3

15) Derive generic sequence network for the following circuit using all four steps, as described in

class and provide detailed explanations of each step. Finish derivations of any parts that were

not fully derived in class.

16) Using the generic sequence network of the circuit from problem 15, do a complete analysis of 

the Single Line-to-Ground (SLG) Fault. Make sure to provide relevant explanations.

a)  Find  

b)  Find all currents

17) Using the generic sequence network of the circuit from problem 15, do a complete analysis of 

the Double Line-to-Ground (DLG) Fault. Make sure to provide relevant explanations.

a)  Find  

b)  Find and  

c) 

Find and all currents

18) Using the generic sequence network of the circuit from problem 15, do a complete analysis of 

the Line-to-Line (LL) Fault. Make sure to provide relevant explanations.

a)  Find  

b)  Find and  

c)  Find and all currents

19) Do the complete analysis for the SLG Fault as in Problem 16 but without o’ grounded.

8/8/2019 ENEE 474 Fall 2010 Homeworks

http://slidepdf.com/reader/full/enee-474-fall-2010-homeworks 4/4

ENEE474 Fall 2010 Homework 

ENEE 474 Page 4

20) Do the complete analysis for the DLG Fault as in Problem 17 but without o’ grounded.

21) Do the complete analysis for the LL Fault as in Problem 18 but without o’ grounded.