Finding h parameters when capacitors and inductors involved with resistors

[sns]

Homework Statement

Find the h parameters of the following systems:-

---L---------C--
:
:
R
:
:
----------------​

L= j5 ohm
C=-j5 ohm
R=1 ohm

Homework Equations

The above questions has to be solved manually as well as simulated (Matlab-simulink).
If anybody can please give a detailed solution explaining all the steps used I will be very grateful.
I only need the manual solution then obviously I can simulate the circuit. Also please explain the significance of giving L and C in ohms without specifying the frequency of supply to be used. Is this circuit only for an a.c. source? Can h parameters vary with time?

Thanks.

 

[Su3liminal]

Well, first write the h-parameters equations:

V1 = h11*I1 + h12*V2
I2 = h12*I1 + h22*V2

And to find the parameters follow the formal procedure:

First, by shorting V2 (that is, making V2 = 0), you can find:
h11 = V1/I1
h12 = I2/I1

Then, by opening the first port (that is, making I1 = 0), you can find:
h12 = V1/V2
h22 = I2/V2

And then after writing the equations, things going to be clear to you. Of course, I would like to help and solve all the project for you, but this isn't how it supposed to be. You have to work out the rest by yourself

 

[sns]

Well, first write the h-parameters equations:

V1 = h11*I1 + h12*V2
I2 = h12*I1 + h22*V2

And to find the parameters follow the formal procedure:

First, by shorting V2 (that is, making V2 = 0), you can find:
h11 = V1/I1
h12 = I2/I1

Then, by opening the first port (that is, making I1 = 0), you can find:
h12 = V1/V2
h22 = I2/V2

And then after writing the equations, things going to be clear to you. Of course, I would like to help and solve all the project for you, but this isn't how it supposed to be. You have to work out the rest by yourself

Well I had done the same and when I do it I start getting the same problems all over again.. Firstly please clear my concepts:
Can h parameters vary with time? Because if we supply voltage V1 ie sinusoidal then currents flowing will not be constant.. thus ratios wouldn't be constant.. Am I correct? Thus will h-parameter be an equation eh?
But if supply d.c. voltage and wait for circuit to be stable... then capacitor ultimately blocks current and inductor just passes current through.. then definitely h-parameters are constant. It'll just be a resistor circuit finally? Is this evaluation correct?

Please help..

 

[rude man]

Well I had done the same and when I do it I start getting the same problems all over again.. Firstly please clear my concepts:
Can h parameters vary with time? Because if we supply voltage V1 ie sinusoidal then currents flowing will not be constant.. thus ratios wouldn't be constant.. Am I correct? Thus will h-parameter be an equation eh?
But if supply d.c. voltage and wait for circuit to be stable... then capacitor ultimately blocks current and inductor just passes current through.. then definitely h-parameters are constant. It'll just be a resistor circuit finally? Is this evaluation correct?

Please help..

1. Your h parameters are not time-variant. They are defined solely by your component values, which are presumably constant. Almost by definition, 2-ports are restricted to ac signals.

2. I'm not going to try to solve the h parameter equations as suggested by su3liminal. That's because they may lead to singularities (& I'm too lazy to find out). In which case what you need to do is rewrite the 2-port equations in terms of a different parameter set. Try the z and the y parameters. Then get a table that gives you the h parameters given the z or y parameters.