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1172 ⏐⏐⏐ SYSTEM ANALYSIS: AN INTRODUCTION
Short circuited
1
E 1 = 0
and y12 ��Y2 (26.37)
The network employed for y21 appears in Fig. 26.42. In this case, Y3 is short circuited, resulting in
IY2 � I2 and IY2 � I2 ��E1Y2 with y 21 �
1′
I 1
I 2
� E1
E 2 � 0
and y21 ��Y2 (26.38)
E 1
+
–
I 1
1
1′
Y 1
Y 1
I Y2
Y 2
FIG. 26.41
Determining y 12.
Y 2
I Y2
Y 3
FIG. 26.42
Determining y 21.
I 2
Y 3
2′
2
2
2′
E 2 = 0
I 2
+
–
E 2
Short circuited
Note that for the p configuration, y 12 � y 21, which was expected
since the impedance parameters for the T network were such that z 12 �
z 21. A T network can be converted directly to a p network using the
Y-D transformation.
The determining network for y 22 appears in Fig. 26.43, and
Short circuited
1
I 1
IY2 I2 Y2 2
E1 = 0 Y1 Y3 E 2
1′
FIG. 26.43
Determining y 22.
2′
+
–