Conductance,Susceptance,Admittance

[walters]

calculation of susceptance in series

Explain what it does to the current and voltage:

Conductance means- to pass current and voltage through the component
easy.
The abilty of a component to allow current

Resistances means- opposition to current through the component

Admittance means- permits current
its a special kind of impendace

Impendance means- the total opposition to AC current

susceptance means-

reactance means- is the property of resisting or impeding the flow of ac current or ac voltage in inductors and capacitors

Capacitive Reactance:
When ac voltage flows through a capacitance an opposing change in the initial voltage occurs, this opposition or impedance to a change in voltage is measured in terms of capacitive reactance.

Capacitive Susceptance means:


Inductive Reactance
When ac current flows through an inductance a back emf or voltage develops opposing any change in the initial current. This opposition or impedance to a change in current flow is measured in terms of inductive reactance.

Inductive Susceptance means:

 

[walters]

adding susceptance value in series

Conductance= DC Conductance
susceptance= frequency conductance
admittance = AC conductance


resistance= DC Opposition
reactance= frequency opposition
impedance= AC opposition

 

[checkmate]

whatis mean by susceptance

I guess you are pretty familiar with impedence, but you aint sure why you need its reciprocal admittance, am I right?
Just to set the record straight,impedence is just the ratio of voltage against current. Don't think too complicated. So it's just a value that describes the V-I characteristics of an element or a circuit. For linear elements, it is complex in general, and probably a function of frequency. You can always find the DC impedence (ie resistance) by substituting freq=0.
Well, it's easy to compute net impedence of elements in series. You simply add them togather.
Correspondingly, it's easy to compute admittance of elements in parallel. You simply add them togather!
And since you know that impedence and admittance are reciprocally related, you can easily convert from one form to the other, and that gives you an easy method to compute net impedence/admittance of a more complicated circuit.
The net impedence of HF circuits use this concept, with the aid of the smith chart, to allow easy addition/multiplication/reciprocation of phasors.
Resistance/Conductance/Reactance/Susceptance are just the real and imaginary parts. You shouldn't bother much about those, and concentrate on the the more important impedence/admittance values as these are the generalized versions.

 

[VVV]

z impedance l inductance suspetance

You are too concerned with the names and their physical significance. They do not need to have any physical significance. They were introduced because for components connected in parallel, they make it easier to calculate the combination: it is easier to add than to multiplyand divide.

Thus, conductance, for example, the inverse of the resistance, simply tells you that the element in the circuit is a pure resistor and the inverse of its value is G. If you have a few of them in parallel, just add them together and you get the inverse of the result. It's just another way of saying:

1/Re=1/R1+1/R2+1/R3+...

Call all of these conductances and write:
G=G1+G2+G3+...

Now you just need to add. Then just do the inverse of the result. It's a lot easier than taking 2 terms at a time and writing: R12=(R1*R2)/(R1+R2)
Then R123=(R12*R3)/(R12+R3) and so on.

Similarly, the other terms were invented. Admittance is the inverse of an impedance. That tells you right away that you are not dealing with a pure resistor, but a combination of resistive and reactive elements.

That is basically it. Just learn the terms, what they mean, how to use them and do not look for a physical significance.
(What is the physical significance of an idea? It does not matter, when you have a good idea).

 

[walters]

how to calculate capacitance from susceptance

I guess you are pretty familiar with impedence, but you aint sure why you need its reciprocal admittance, am I right?
Yes

physical significance of Conductance? what would it be?
Physcial significance of Susceptance? what would it be?
Physcial significance of admittance? what would it be?


Most books and electronic classes forus only on looking at a circuit design
and Analyze it like this

resistance= DC Opposition
reactance= frequency opposition
impedance= AC opposition


But in EE design classes they focus on this

Conductance= DC Conductance
susceptance= frequency conductance
admittance = AC conductance

I don't know how to look at a circuit,network or design like this how do i do this
and analyze the circuit,network or design looking at it like this?

 

[checkmate]

capacitive susceptance

I think you are confusing yourself when you want to know what the physical meanings of those terms are.

Let's start with the simplest, resistance. As I said, it's simply a V-I characteristic of elements called resistors. Nowhere in Ohm's Law does it explain what causes resistance. It's just very simply V/I, because it was DEFINED to be so.

Now, impedence is simply Z=V/I, with its real part termed as resistance and imaginary part termed as reactance. If you take its reciprocal, ie admittance Y=1/Z. The real part of admittance is termed conductance, and the imaginary part termed susceptance. All these are merely definitions and terminology. They only state the V-I characteristics of an element, but offers no description or explaination for them.

In science, we always aim to find the most general laws. Same with electronics. AC is more general than DC, where DC is just a special case of AC with zero frequency. Same with complex numbers being more general than real numbers. You don't really have to place too much emphasis on the real/imaginary parts of impedence/admittance. They are merely terminology. The reactance of an element is not very useful in general if its impedence value is not provided.