### Electrical Circuit Network Theorems Definitions and Key Facts

**Definition Terms of a Network Theorems and key facts**

**Active network **

A Network containing one or more sources of electro motive force ( e.m.f) is known as an active network.

**Branch **

A single path containing one simple element which connects one node to any other node is know as branch.

**Bilateral Circuit **

A circuit having identical properties in either direction is know as bilateral circuit. Transmission line is bilateral.

**Circuit **

A circuit is a conducting part through which either an electric current flows or is intended to flow.

**Linear Circuit **

A linear circuit is one whose parameters are constant.. do not change with voltage or current.

**Non-Linear Circuit **

It is that circuit whose parameters change with voltage or current.

**Node**

A point at which two or more elements have a common connection is called a node.

**Parameters**

The various elements of an electric circuit are called its parameters like resistance, inductance and capacitance. These may be lumped or distributed.

**Unilateral Circuit**

It is that circuit whose properties changes with the direction of its operation. A vaccume tube rectifier is a unilateral circuit.

**Key facts on Network Theorems**

- Kirchhoff's law is applicable to ac ( alternation current) as well as DC ( direct current) circuits.
- An ideal current source has zero internal conductance.
- A closed path made of several branches of the network is known a loop.
- An ideal voltage source is that which has zero internal resistance.
- A passive network has neither source of current nor source of e.m.f. ( electro motive force).
- The relationship between voltage and current is same for two opposite directions of current in case of bilateral network.
- A passive network has neither e.m.f ( electro motive force) source nor current source.
- Heater coil is not a non-linear element.
- Milman's theorem enables a number of voltage for current source to be combined directly into a single voltage or current source.
- The thevenin's theorem is applicable to a network of the alternating current and direct current circuit both.
- For open circuited condition of thevenin's theorem, all sources of electromotive force in the network are replaced by their internal impedance.
- Reciprocity theorem is valid for passive network only.
- In compensation theorem a network containing generator can be replaced by its zero internal impedance.
- The most important feature of superposition theorem application is to find direct current level in a network that has both sources.
- Open circuit voltage is the p.d. between two points when the impedance between these points is infinity.
- Norton's theorem reduce a two terminal network to a constant current source and an impedance in parallel.
- The superposition theorem requires as many circuits to be solved as there are sources.
- For a maximum power transfer, according to maximum power transfer theorem, source impedance must be complex conjugate of load impedance.
- In case the delta connected circuit, when one resistor is open, power will be reduced by 1/3.
- The superposition theorem is applicable to linear responses only.

## 3 comments:

Thanks for giving such a nice defination.

i have joined you on

facebook fan pageyour blog is good.

I think you have excellent knowledge on Network Theorems. This is my good luck that I found your post, I was looking for. It is very useful for my assignment.

Post a Comment