Introduction to Electric Circuits

206 Two-port networks V 1 -- ZllI1 + z1212 (9.1) V2 = Z21 I, + Z2212 (9.2) In matrix form these may be written EVil Zll z12] [11 ...

9.2 The impedance or z-parameters 207 Example 9.1 Determine the z-parameters of the T-circuit shown in Fig. 9.3. Figure 9.3 11 Z ...

208 Two-port networks 9.3 THE ADMITTANCE OR y-PARAMETERS Set 2: If V~ and V2 are the independent variables then the dependent va ...

9.2 The admittance or y-parameters 209 Example 9.2 Determine the admittance parameters for the T-circuit shown in Fig. 9.3. Solu ...

210 Two-port networks Finally, from Equation (9.14), Y22 = I2/V2 with V~ = 0. We have seen that with V1 = O, 12- 15V2/125 = 3V2/ ...

9.5 The inverse hybrid or g-parameters 211 transistors where an additional subscript 'e', 'b' or 'c' is used, depending upon the ...

212 Two-port networks " g22 is the output impedance (go) and is measured in ohms as V2/12 with V 1 : O: g22- (V2/I2)lv,=o (9.28) ...

9.6 The transmission or ABCD-parameters 213 Therefore h21-~. 12/1, = -Z3/(Z2 + Z3) Putting in the impedance values, h21 = -5/10 ...

214 Two-port networks O v, T O Figure 9.7 1~! I2 2-port network ! I2 O+ O- and are also particularly useful for the analysis of ...

7 The inverse transmission parameters 215 V 2 = A'V 1 + B'I 1 (9.40) I2 = C'V~ + D'I~ (9.41) In matrix form we have A' B' Ic A ...

216 Two-port networks To find B and D we short circuit the output port to make V2 = 0. Then V1 = IzZ and I~ = I2. From Equation ...

7 The inverse transmission parameters 217 The receiving-end current is given by I2 = 500 kVA/2 kV = 250 A Because the receivin ...

218 Two-port networks Therefore I,/(1 + ZY)= V1/Z Also, we saw above that 12 B = V,/I2 = Z In matrix form = I,/(1 + ZY) so that ...

9.8 Cascaded two-port networks 219 9.8 CASCADED TWO-PORT NETWORKS +O vl --O Figure 9.11 I~! , ,------Iu Network 1 + 11o = 12i + ...

220 Two-port networks We saw in Example 9.7 that for a shunt admittance A = 1, B = 0, C = Y and D = 1. Also, from Example 9.4 we ...

9.8 Cascaded two-port networks 221 +C I1 ~ 0 0 [ --~y Figure 9.14 Z I2 ] 0 0 Y -0 0 0 0 0 1 2 3 O+ V2 --O- For sections 1 and 3, ...

222 Two-port networks The ABCD-parameters of a T-network T-networks arc commonly used for LC filters and for attenuation section ...

9.8 Cascaded two-port networks 223 Nominai-T representation of 'medium length' power transmission lines In power transmission li ...

224 Two-port networks V1 0 [Ii1=[~ X,/nl[~ 2] (9.61) Example 9.12 Obtain the ABCD-parameters for a practical transformer. Soluti ...

9.9 Characteristic impedance (Zo) 225 9.9 CHARACTERISTIC IMPEDANCE (2'0) The characteristic impedance of a symmetrical two-port ...