Chapter 3 Problems Solutions
3.1 Based on the cross product of [3.2] with the vectors B and I separated by 30 , the magnitude of the force is
F = li ( t ) B ( t ) sin ( 30 ) = ( 0.25 ) ( 2cos t ) ( 5cos t ) ( 0.5 )
F = 1.25cos 2 t = 0.625 + 0.625cos ( 2 t
Chapter 7 Problems Solutions
7.1 For any particular value of I f ,
Xs =
VL / 3
IL
where VL is read from the OCC and I L is read from the SCC.
The OCC and SCC data from Fig. 7.16 are used in the following MATLAB program
Xs1.m to calculate and plot X s vs.
Chapter 6 Problems Solutions
6.1 (a) Synchronous speed for 60-Hz excitation is given by [6.12].
ns = 120 f / p = 7200 / p
Specific values for ns are tabulated.
ns
3600
1800
1200
p
2
4
6
The slip at rated shaft speed should be less than 10 percent. The onl
Chapter 5 Problems Solutions
5.1 Based on [3.10], the indicated voltages across the conductor sides of Fig. 5.8 for the case
of a time-varying B-field are given by
v1 = v2 =
d
la Bg ( , t ) r
dt
(
v1 = v2 = la Bg ( , t ) r
)
0< <
dBg ( , t )
d
+ la r
dt
d