Join 60,000+ competitive exam aspirants
or with email
Your Cart
SubtotalтВ╣0
TotalтВ╣0
Examoogle тАв User тАв info@examoogle.com тАв EE-2024-8821
Chapter 1 of 12 тАв Page 1 of 248ЁЯФТ Protected PDF тАв Watermarked
Join 60,000+ competitive exam aspirants
The value of ABCD constants for short transmission line are respectively
Z, 0, 1 and 1
0, 1, 1 and Z
1, Z, 0 and 1
1, 1, Z and 0
1, Z, 0 and 1
For a short transmission line, the shunt admittance is assumed to be zero due to its small length and voltage. The ABCD constants are derived from the simple series impedance model where the sending end voltage and current are related to receiving end values as VSтАЛ=VRтАЛ+IRтАЛZ and ISтАЛ=IRтАЛ.
For a short transmission line, the shunt admittance is assumed to be zero due to its small length and voltage. The ABCD constants are derived from the simple series impedance model where the sending end voltage and current are related to receiving end values as VSтАЛ=VRтАЛ+IRтАЛZ and ISтАЛ=IRтАЛ.
VSтАЛ=VRтАЛ+IRтАЛZ
ISтАЛ=IRтАЛ
[VSтАЛISтАЛтАЛ]=[10тАЛZ1тАЛ][VRтАЛIRтАЛтАЛ]
In a short transmission line (length < 80 km), the shunt capacitance effect is neglected. By applying Kirchhoff's Voltage and Current Laws to a series impedance Z=R+jXLтАЛ representing the line, we obtain the transmission line equations: VSтАЛ=AVRтАЛ+BIRтАЛ and ISтАЛ=CVRтАЛ+DIRтАЛ. Comparing these with VSтАЛ=1тЛЕVRтАЛ+ZтЛЕIRтАЛ and ISтАЛ=0тЛЕVRтАЛ+1тЛЕIRтАЛ, we identify the parameters as A=1,B=Z,C=0,D=1.
Short transmission lines have a length typically less than 80 km.
The shunt capacitance C is ignored because it is negligible for short distances.
The line is represented as a pure series impedance Z=R+j╧ЙL.
The transmission matrix satisfies the reciprocal property ADтИТBC=1.
Simplicity in calculation and modeling.
Efficient for preliminary voltage drop analysis.
Not suitable for long transmission lines due to neglect of shunt effects.
Accuracy decreases as frequency or line length increases.
Distribution line analysis.
Short-distance rural electrification.
The matrix for a short transmission line is [10тАЛZ1тАЛ].
Option A is incorrect as it swaps the constants, and Option B and D represent invalid configurations for this model.
C is correct тАФ The transmission (ABCD) constants for a short transmission line are defined as A=1, B=Z, C=0, and D=1.
Always remember that for reciprocal networks, ADтИТBC=1. Short lines always satisfy this, where (1)(1)тИТ(Z)(0)=1.