POWER SYSTEM INTRODUCTION priyank pulkit rads praveer

Presented by:Presented by:

Praveer DubeyPraveer DubeyPriyank JainPriyank JainPulkit KhoslaPulkit KhoslaRadhika SharmaRadhika Sharma

KNOW YOUR KNOW YOUR POWER POWER UNIT 1 & UNIT 2UNIT 1 & UNIT 2

THE NEED FOR THE THE NEED FOR THE PRIMER PRIMER

Electricity to EconomicsElectricity to Economics

Electricity has become the lifeblood of the modern world.

The electricity sector in India supplies the world's 5th largest energy consumer ,accounting for 4.0% of global energy consumption by more than 17% of global population.[11]

Introduction Introduction

All of us use Energy.Variable sources of energy.Various fields use different kind of energy.Most versatile form of commercial energy.

Commercial Energy Non Commercial Energy

Coal Fire wood & cow dung

Oil &Gas Agricultural waste

Nuclear Sunlight(for drying things)

Hydro Animals(for transport)

Solar ,Wind ,Biomass etc. Human activities(farming,weaving)

Total Energy DigTotal Energy Dig

Commercial Energy

Non Commercial Energy

Total Energy

Commercial Energy Supply:Commercial Energy Supply:

Electric energy consumptionElectric energy consumption

Fig:2 Electric energy consumption

Power as infrastructurePower as infrastructure

Power is the Backbone of the Indian economy.

Power sector has a growth rate of 6.79%(2010-2011).[1]

At the time of Independence our generating capacity was 1361(MW). [2.]

Our present generating capacity is 176990.40(MW).[3.]

RevenueRevenue

“India's power sector will generate a revenue of Rs 13 lakh crore (US $ 294 billion) during the 12th five year plan (2012-17)” .

- P. Uma Shankar

Union power secretary[4.]

Features of ElectricityFeatures of Electricity

Today electricity plays key role in society.

It is key to economic growth of the country.

It can be economically transported over long distance.

Easily converted to heat ,light , shaft power, communication or medical equipments.

There is no option but to depend on ELECTRICITY……

Invention of electricityInvention of electricity

1600 AD the history of electricity begins with William Gilbert, a physician, who coined the expression "electrica" in his famous book.

In 1660, Otto von Guericke invented a machine that produced static electricity, this was the first electric generator.

In 1729, Stephen Gray discovered the principle of the conduction of electricity.

Ben Franklin's important discovery was that electricity and lightning were one and the same. Ben Franklin's lightning rod was the first practical application of electricity.

THOMAS EDISON helped change everyone's life -- he perfected his invention -- the electric light bulb.


Michael Faraday invented the electric motor in 1821.

“Communism=Socialism + Electricity”

----Lenin , Soviet Union Architect


Flux in power sector of IndiaFlux in power sector of India

Government in 1991Government in 1991The government in 1991, liberalized the sector

and opened it for foreign and private investments to increase the availability of funds for the power sector.

Around 189 projects, with an expected capacity of 75 GW, were proposed; however, only a few of these projects cleared the approval process.

Enron Case:Enron Case:

Orissa ReformOrissa Reform

Electricity Act 2003Electricity Act 2003

The Electricity Act 2003, which came into effect from June 10, 2003, replaced the earlier laws, acts governing the Indian power sector. The bill sought to provide a legal framework for enabling reforms and restructuring the power sector.

With the enactment of the Electricity Act 2003 and implementation of open access, the market structure in the power sector changed from the old single buyer structure to a multi-buyer model.

UNDERSTANDING THE UNDERSTANDING THE POWER SYSTEMPOWER SYSTEM

ELECTRICITY :ELECTRICITY :

“ An Invention that has changed the quality of Man’s Life”

Some basic questions most of us have in their mind :

Have you ever wondered how electricity generated thousands of miles away reaches you?

Why lightning that strikes at a far off place affects our power supply?

Why erratic monsoons result in a power shortage?

How can excess power generated in one state be used to solve power shortage in the other?

To understand the root of these questions, and to assess and effectively analyze their viability, as power managers, we first would need to understand how a Power System actually works….

BASICS OF ELECTRICITY:BASICS OF ELECTRICITY:

Measuring Electricity :

There are three basic entities in electricity :

1.Voltage:

Potential difference between two points.

SI Unit : Volts

2.Current :

The Current is the flow of electric charge (electrons or ions).

SI Unit : Amperes .

3. Resistance:

‘Resistance’ is obstruction in the flow of current. This is an inherent

property of all materials.

SI Unit : Ohms.

Power system is defined as the network of generating stations, substations and power lines.

Power system may be considered as one of the largest and most expensive system of all manmade systems.

POWER SYSTEM :POWER SYSTEM :

COMPONETS OF POWER SYSTEM :COMPONETS OF POWER SYSTEM :

Generation:

“ Process by which electric power is produced. It may be termed as production stage.”

It can be done in different ways using different fuels: Thermal: Fuels can be coal, gas, oil, and biomass. Hydro Nuclear Wind Solar Geothermal

The power system network and operation can be divided into three broad sections:

COMPONETS OF POWER SYSTEM :COMPONETS OF POWER SYSTEM : Transmission & Distribution:

“The process by which the generated electric power is transmitted and distributed to the end users.”

Distribution is more like the retail stage and operates at much lower voltages.

Transmission is bulk transport and is generally done at high voltages. Generally between power plants and sub stations.

COMPONETS OF POWER SYSTEM :COMPONETS OF POWER SYSTEM : Utilization:

“The process of Utilizing Electricity for various purposes.”

The uses of electricity can be generally classified as :IndustrialDomestic Agricultural.Commercial

“Generation, transmission, distribution and utilization need to work in close coordination for healthy operation of power system.”

Schematic Diagram of a Power SystemSchematic Diagram of a Power System

BASICS OF POWER SYSTEM:BASICS OF POWER SYSTEM:

Understanding Electricity flow – The electric circuit:

“ Circuit is interconnection of wires and devices. It is the path of flow of current.”

Electricity always travels in closed loops .



It states that the current through a conductor between two points is directly proportional to the potential difference or voltage across the two points, and inversely proportional to the resistance between them.The mathematical equation that describes this relationship is:

I = V/R

Ohm’s Law



WHAT IS POWER ?

“Electric power is defined as the rate at which electrical energy is transferred by

an electric circuit.”

POWER = VOLTAGE X CURRENT X COSØ

For dc circuit COSØ=1.

It is measured in watts.

The above equation can be transformed as :

Power = Current x Current x Resistance= (Current)2 X Resistance



WHAT IS UNIT ?

“ The unit is measure of electric energy.”

ENERGY = POWER X TIME

It is measured in kilowatt - hour (KWh).

One unit is the energy consumed when power is 1000W in period of 1 hour.

Units = No. of Hours of operation x Power consumed

“The calculation of power supplied to a consumer is based upon the ‘Units’ of electricity consumed by him.”

WHAT IS DC & WHAT IS AC ?WHAT IS DC & WHAT IS AC ?

DIRECT CURRENT (DC):

“Direct current (DC) is the unidirectional flow of electric charge. It is produced

by sources such as batteries, thermocouples, solar cells, etc.”

In direct current, the electric charges flow in a constant direction,

distinguishing it from alternating current (AC).

Fig3.

WHAT IS DC & WHAT IS AC ?WHAT IS DC & WHAT IS AC ?ALTERNATING CURRENT (AC):

“An alternating current (AC) is an electric current whose direction reverses

cyclically, as opposed to direct current (DC), whose direction remains constant.

The usual waveform of an AC power circuit is a sine wave.”

The AC is generated based on the principle of electromagnetic induction

.

AC V/S DCAC V/S DC

All power systems today operate on AC, because of its

distinct advantages over DC as stated as below:

WHY IT IS NECESSARY TO TRANSFORM VOLTAGE WHY IT IS NECESSARY TO TRANSFORM VOLTAGE ??

In Transmission , Most of the Power is lost in the wires in the

form of heat.

It can be seen that for a fixed value of power , if voltage is increased , current will

be decreased.

“ Power is generated at 11kV or 22 kV but generally transmitted at 132 kV ,400 kV , 765 kV.”

WHAT IS FREQUENCY?WHAT IS FREQUENCY?

FREQUENCY:

“In an AC circuit, the voltage and current oscillate with time. The number of

times the voltage or current wave oscillates in a second is known as frequency.

Measured in Hertz.

In India, the frequency is 50 Hz. That is, the voltage and current oscillate

at 50 times per second.

HOW DOES ELECTRIC POWER FLOW?HOW DOES ELECTRIC POWER FLOW?

“As power is a function of the voltage and current, the flow of electrons in a

circuit guides the flow of Electric power.”

The Power which is capable of doing work is called active

power.

In DC circuits there is only Active power.

An AC circuit has two types of power components--- Active &

Reactive.

REACTIVE POWERREACTIVE POWERAC CIRCUITAC CIRCUITTHREE PHASE SYSTEM THREE PHASE SYSTEM

WHAT IS REACTIVE POWER?WHAT IS REACTIVE POWER?

Two kinds of power flow in an AC circuit –

Active power which does some visible work – like turning a fan or a motor.

Reactive power just goes back and forth in the circuit. But it is quite necessary to have reactive power flowing in an AC circuit to make a motor turn or a fan move.

REACTIVE POWER ANALOGIES

The ‘loft’ in a baseball throw

The ‘lift’ in an airplane

The “loft” analogyThe “loft” analogy

The upward component of the trajectory does not contribute to getting the ball any closer to the hitter, but without it the ball won’t get there.

The aircraft “lift” analogyThe aircraft “lift” analogy

Lift does not get you any closer to your destination, but without it you are driving ,not flying.

WHY WHY DODO WE NEED REACTIVE POWER? WE NEED REACTIVE POWER?

While active power is the energy supplied to run a motor ,heat a home, or illuminate an electric light bulb, reactive power provides the important functions of regulating voltage.

Reactive power is used to provide the voltage levels necessary for active power to do useful work.

Reactive power is essential to move active power through the transmission and distribution system to the customer.

Voltage and reactive Power planning Voltage and reactive Power planning and assessment Practicesand assessment PracticesKey Principles: Reactive power cannot be transmitted over a long distance

or through power transformers due to excessive reactive power losses.

Reactive power supply should be located in close proximity to its consumption.

Sufficient static and dynamic voltage support is needed to maintain voltage levels within an acceptable range.

Sufficient reactive power reserves must be available to regulate voltage at all times.

Transmitting reactive powerTransmitting reactive power

Reactive power cannot be effectively transmitted across long distances or through power transformers due to high heat losses.

Reactive Power locationReactive Power location

Reactive power should be located in close proximity to its consumption.

Power factorPower factor

The average power dissipation given by

is termed the Active Power in the circuit and is measured in watts (W)

The product of the r.m.s. voltage and current VI is termed Apparent Power, S. To avoid confusion this is given the units of volt amperes (VA)

ContiConti……From the above discussion it is clear that

• In other words, the active power is the apparent power times the cosine of the phase angle.

• This cosine is referred to as the Power Factor

• Power Factor =Active power(in watts)/Apparent power (in volt amperes)

• Power factor= P/S=

Facts about power factorFacts about power factor

Power factor is the measure of the degree to which the system is utilizing the power fed in it.

Its value is always between 0 and 1

When there is no reactive power, the p.f. is 1

Lower value of power factor [near to 0] means, the circuit will have more reactive power

Power Factor CorrectionPower Factor Correction

Power factor is particularly important in high-power applications.

Inductive loads have a lagging power factor.Capacitive loads have a leading power factor.Many high-power devices are inductive.◦ A typical AC motor has a power factor of 0.9 lagging◦ The total load on the national grid is 0.8-0.9 lagging◦ This leads to major efficiencies.◦ Power companies therefore penalize industrial users

who introduce a poor power factor.

Power Factor CorrectionPower Factor Correction

The problem of poor power factor is tackled by adding additional components to bring the power factor back closer to unity.

◦ A capacitor of an appropriate size in parallel with a lagging load can ‘cancel out’ the inductive element

◦ This is Power Factor Correction

◦ A capacitor can also be used in series but this is less common (since this alters the load voltage)

Three-Phase systemsThree-Phase systems

So far, our discussion of AC systems has been restricted to single-phase arrangement(As in conventional domestic supplies)

In high-power industrial applications we often use three-phase arrangements.◦ These have three supplies, differing in phase by

120 °◦ Phases are labeled red, yellow and blue (R, Y &

B)

RelationshipRelationship between the phases between the phases

Relationship between the phases in a three-phase arrangement

How Is Power Utilized ?How Is Power Utilized ?

Consumers can be divided into four broad Consumers can be divided into four broad categories:categories:

Power Utilized Percentages [5.]Agriculture: 23%

Industrial: 35.9%

Commercial: 8%

Domestic: 24%

Others: 9%

Utilisation can be viewed from two Utilisation can be viewed from two points of view points of view

Consumer Point Of View

Utility Point Of View

Consumer Point Of ViewConsumer Point Of View

Calculating Power ConsumptionCharge may depend on

Amount of load connected Time of use of electricity Power factor

How Can We Reduce ConsumptionHow Can We Reduce Consumption

Use natural lighting and cooling methods as much as possible.

CFL’s and Tube lights are much more efficient.

Switch off when you don’t need a bulb or fan.

Power down computers, televisions, playstations etc when not in use.

Encourage others to conserve.

Potential to save in offices and Potential to save in offices and factories is much morefactories is much more

Motors should be sized properly.

Unwanted motors should be turned off.

Pipes should be properly insulated.

Energy leakage must be plugged.

Process improvements should be carried out to improve energy efficiency.

Protecting Your InterestsProtecting Your Interests

Prevention of electric shocks.

Protecting electrical equipment.

Keeping track of quality of power.

Electric Shocks Electric Shocks

Equipments should be connected to earth.

Put off main switch while doing repairs.

Ensure wires are not exposed.

Wear rubber footwear while working on equipments.

Plug points should be covered or should be out of reach of children.

Electric ShocksElectric Shocks

Earth leakage Circuit breakers can be employed.

Tall buildings are protected by lightning arrestors.

Equipment ProtectionEquipment Protection

Circuit breakers.Fuses.UPS

Power Supply QualityPower Supply Quality

Voltage variations.

Power interruptions.

Frequency and harmonic components.

Efficiency And StandardsEfficiency And Standards

ISI mark with relevant standard number.

Ex. IS:325- 3 phase induction motors IS:374- ceiling fans IS:2418- Tube lights

IS:418- ordinary bulbs[6.]

Test instruments

Grievances and RedressalGrievances and Redressal

Errors in electricity bill.

Erratic power supply.

Load shedding.

Damage of equipment due to high or low voltages.

Electric shock accidents.

Undue delay in getting a connection.

Utility Point Of ViewUtility Point Of View

Three important issues that utility is concerned with in an area of utilisation.

Load Behavior Quality Issues Safety issues

Load BehaviourLoad Behaviour

Load depends on the kind of equipment consumers use and the value of load.

Load curve

Quality IssuesQuality Issues

Preventive maintenance.Problem handling.

Safety and ProtectionSafety and Protection

Utility has to ensure that power equipments are not damaged by lightning or by short circuit.

Safety of workers repairing the line has to be ensured.

References:References:

[1].[Source – CSO, MOSPI, Government of India][2.][Source-Decide & Confidence http://www.dnb.co.in][3.][Source – Office of Economic Adviser, MOC&I, Govt of India][4.][Source :Times Of India 22Jul 2011][5.][Power Utilisation Percentage][Source: CSO, MOSPI,

Government of India][6] ISI values:[source : Bureau of Indian Standards.Govt of India][Fig3.]Voltage time graph[Source : Wikipedia]Common source for images:[Source : wikipedia.org & Google

images]

[Exhibit2.2Post Reform Framework][Source:D&BIndustry Research Service]

[Box 2.3][Enron Case][Source:D&BIndustry Research Service]

[Box 2.4][Orissa] [Source:D&BIndustry Research Service]

[Exhibit2.1Regulation For power sector][Source: D&BIndustry Research Service]

[Exhibit2.3Segment wise impact of Electricity Act2003][Source:D&BIndustry Research Service]

Book referred : Know Your Power

POWER SYSTEM INTRODUCTION priyank pulkit rads praveer

Education

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