Hadi Saadat
Professor of Electrical Engineering
Milwaukee School of Engineering
Milwaukee, Wisconsin
McGraw-Hill, Inc.
,
, CONTENTS
1 THE POWER SYSTEM: AN OVERVIEW 1
2 BASIC PRINCIPLES 5
3 GENERATOR AND TRANSFORMER MODELS;
THE PER-UNIT SYSTEM 25
4 TRANSMISSION LINE PARAMETERS 52
5 LINE MODEL AND PERFORMANCE 68
6 POWER FLOW ANALYSIS 107
7 OPTIMAL DISPATCH OF GENERATION 147
8 SYNCHRONOUS MACHINE TRANSIENT ANALYSIS 170
9 BALANCED FAULT 181
10 SYMMETRICAL COMPONENTS AND UNBALANCED FAULT 208
11 STABILITY 244
12 POWER SYSTEM CONTROL 263
i
, CHAPTER 1 PROBLEMS
1.1 The demand estimation is the starting point for planning the future electric
power supply. The consistency of demand growth over the years has led to numer-
ous attempts to fit mathematical curves to this trend. One of the simplest curves
is
P = P0 ea(t−t0 )
where a is the average per unit growth rate, P is the demand in year t, and P0 is
the given demand at year t0 .
Assume the peak power demand in the United States in 1984 is 480 GW with
an average growth rate of 3.4 percent. Using MATLAB, plot the predicated peak
demand in GW from 1984 to 1999. Estimate the peak power demand for the year
1999.
We use the following commands to plot the demand growth
t0 = 84; P0 = 480;
a =.034;
t =(84:1:99)’;
P =P0*exp(a*(t-t0));
disp(’Predicted Peak Demand - GW’)
disp([t, P])
plot(t, P), grid
xlabel(’Year’), ylabel(’Peak power demand GW’)
P99 =P0*exp(a*(99 - t0))
The result is
1