This document discusses Y or admittance parameters, which describe the behavior of linear two-port electrical systems using equations that relate currents and voltages. The Y parameters - Y11, Y12, Y21, and Y22 - are short circuit admittances that can be used to find the currents at each port if the voltages are known and one port is short circuited. Y parameters are useful for analyzing two-port networks and assessing the small signal stability of electrical systems.

1. Y- parameter
presented by-
Bhupendra Kumar

2. 
 Y parameters of two port networks are known as short
circuit admittance parameters.
 Y parameters are used to describe the behavior of linear
electrical systems.
Y parameters

3. 
Short circuit admittance
or (y) parameters
I1=Y11V1+Y12V2 ……………… 1
I2=Y21V1+Y22V2 ………………. 2

4. 
 The constants Y 11, Y 12, Y 21, and Y 22 are called the
admittance or Y-parameters of the two-port network.
 Equations (1) and (2) are called the standard
equation or defining equations of the Y-parameters.

5. Now if V 1 = 0 the input port is short circuit
and
if V2 = 0 the output port is short circuit

6. Y 11 and Y 22 are driving-point admittance at port 1 and port
2.
Y 12 and Y 21 are known as transfer admittance.
Y 11 is known as short circuit input admittance.
Y 12 is known as short circuit reverse transfer admittance.
Y 21 is known as short circuit forward transfer admittance.
Similarly, Y 22 is known as short circuit output admittance.

7. 
Find the Y parameters for the
two-port network shown

9. 
 The admittance parameters describe the currents in
terms of the voltages
 Admittance parameters are short circuit parameters.
 They are also used to find small signal stability of a
system.
summary