TWO PORT NETWORK PARAMETERS (Y PARAMETERS) ECS LAB

AIM:  To determine “Y” parameters of a given two port passive network.

APPARATUS REQUIRED:

Sl. No.	Name of the Component	Specifications	Quantity
1	Resistors	1 KW	2
		2.2 KW	1
2	R.P.S.	0-30 V	1
3	D. C. Voltmeter	0-50V	1
4	D.C Ammeters	0-50 mA	2
5	Bread board		1

TWO PORT NETWORK PARAMETERS(Z) - ECS LAB (II year II sem)

AIM:  To determine Z parameter of a given two port passive network.

APPARATUS REQUIRED:

Sl. No.	Name of the Component	Specifications	Quantity
1	Resistors	1 KW	2
		2.2 KW	1
2	R.P.S.	0-30 V	1
3	D. C. Voltmeter	0-50V	1
4	D.C Ammeters	0-50 mA	2
5	Bread board		1

RECIPROCITY THEOREM - ECS LAB (II year II sem)

RECIPROCITY THEOREM

AIM: - To verify Reciprocity theorem                                                 

APPARATUS REQUIRED:

Sl. No.	Name of the Component	Specifications	Quantity
1	Resistors	1 KW	2 1
		2.2 KW
2	D.R.P.S.	0-30 v	1
3	Ammeters	0-20 mA	1
4	Bread board		1

SUPERPOSITION THEOREM - ECS LAB (II year II sem)

SUPERPOSITION THEOREM

AIM: - To verify Superposition theorem                                              

APPARATUS REQUIRED:

Sl. No.	Name of the Component	Specifications	Quantity
1	Resistors	1 KW	2 1
		2.2 KW
2	D.R.P.S.	0-30 v	1
3	Ammeters	0-20 mA	1
4	Bread board		1

THEVENIN'S , NORTON'S AND MAXIMUM POWER TRANSFER THEOREM - ECS LAB (II year II Sem)

THEVENIN’S THEOREM

AIM:  To verify Thevenin’s theorem

APPARATUS REQUIRED:

                                                                                                                    

Sl.  No.	Name of the component	Specifications	Quantity
1	Resistors	1 KW	2
		2.2 KW	1
3	Regulated Power Supply (RPS)	0-30 V	1
4	Voltmeter	0-20V	1
5	Ammeter	0-20 mA	1
6	Decade Resistance Box (DRB)	10W-1MW	1
7	Bread Board		1
8	Multi meter		1

Single Three Phase Transformer vs bank of three Single Phase Transformers

It is found that generation, transmission and distribution of electrical power are more economical in three phase system than single phase system. For three phase system three single phase transformers are required. Three phase transformation can be done in two ways, by using single three phase transformer or by using a bank of three single phase transformers. Both are having some advantages over other. Single 3 phase transformer costs around 15% less than bank of three single phase transformers. Again former occupies less space than later. For very big transformer, it is impossible to transport large three phase transformer to the site and it is easier to transport three single phase transformers which is erected separately to form a three phase unit. Another advantage of using bank ofthree single phase transformers is that, if one unit of the bank becomes out of order, then the bank can be run as open delta.

Connection of Three Phase Transformer

A Variety of connection of three phase transformer are possible on each side of both a single 3 phase transformer or a bank of three single phase transformers.

Transformer Insulating Oil and Types of Transformer Oil

Insulating oil in an electrical power transformer is commonly known as Transformer Oil. It is normally obtained by fractional distillation and subsequent treatment of crude petroleum. That is why this oil is also known as Mineral Insulating Oil. Transformer Oil serves mainly two purposes one it is liquid insulation in electrical power transformer and two it dissipates heat of the transformer i.e. acts as coolant. In addition to these, this oil serves other two purposes, it helps to preserve the core and winding as these are fully immersed inside oil and another important purpose of this oil is, it prevents direct contact of atmospheric oxygen with cellulose made paper insulation of windings, which is susceptible to oxidation.

Types of Transformer Oil

Generally there are two types of Transformer Oil used in transformer,

1. Paraffin based Transformer Oil

2. Naphtha based Transformer Oil

Core of Transformer and Design of Transformer Core

In a electrical power transformer there are primary, secondary and may be tertiary windings. The performance of a transformer mainly depends upon the flux linkages between these windings. For efficient flux linking between these winding one low reluctance magnetic path common to all windings, should be provided in the transformer. This low reluctance magnetic path in transformer is known as core of transformer.

Influence of Diameter of Transformer Core

Let us consider, the diameter of transformer core be ′D′

Transformer Cooling System and Methods

The main source of heat generation in transformer is its copper loss or I2R loss. Although there are other factors contribute heat in transformer such as hysteresis & eddy current losses but contribution of I2R loss dominate them. If this heat is not dissipated properly, the temperature of the transformer will rise continually which may cause damages in paper insulation and liquid insulation medium of transformer. So it is essential to control the temperature within permissible limit to ensure the long life of transformer by reducing thermal degradation of its insulation system. In Electrical Power transformer we use external transformer cooling system to accelerate the dissipation rate of heat of transformer.There are different transformer cooling methods available for transformer, we will now explain one.

Parallel operation of Transformers

It is economical to installed numbers of smaller rated transformers in parallel than installing a bigger rated electrical power transformer. This has mainly the following advantages,

1) To maximize electrical power system efficiency: Generally electrical power transformer gives the maximum efficiency at full load. If we run numbers oftransformers in parallel, we can switch on only those transformers which will give the total demand by running nearer to its full load rating for that time. When load increases we can switch no one by one other transformer connected in parallel to fulfill the total demand. In this way we can run the system with maximum efficiency.

2) To maximize electrical power system availability: If numbers of transformers run in parallel we can take shutdown any one of them for maintenance purpose. Other parallel transformers in system will serve the load without total interruption of power.

3) To maximize power system reliability: if nay one of the transformers run in parallel, is tripped due to fault other parallel transformers is the system will share the load hence power supply may not be interrupted if the shared loads do not make other transformers over loaded.

4) To maximize electrical power system flexibility: Always there is a chance of increasing or decreasing future demand of power system. If it is predicted that power demand will be increased in future, there must be a provision of connecting transformers in system in parallel to fulfill the extra demand because it is not economical from business point of view to install a bigger rated single transformer by forecasting the increased future demand as it is unnecessary investment of money. Again if future demand is decreased, transformers running in parallel can be removed from system to balance the capital investment and its return.