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SUMMER TRAINING PROJECT REPORT CONTENTS 1. ACKNOWLEDGEMENT 2. ABOUT THE ORGANIZATION: i. ABOUT NORTH DELHI POWER LTD. ii. POLICY
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SUMMER TRAINING PROJECT REPORT

CONTENTS

1. ACKNOWLEDGEMENT

2. ABOUT THE ORGANIZATION:

i. ABOUT NORTH DELHI POWER LTD.

ii. POLICY

iii. SUSTAINABILITY

iv. AWARDS AND RECOGNITION

3. TRAINING LESSONS:

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i. INTRODUCTION

ii. CHAPTER 1: DISTRIBUTION TRANSFORMERS

iii. CHAPTER 2: POWER TRANSFORMERS

iv. CHAPTER 3: TIPS FOR SAVING ENERGY

v. CHAPTER 4: FAQs

vi. CHAPTER 5: ENERGY AWARENESS

.

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ABOUT THE ORGANIZATION

NORTH DELHI POWER LIMITED

North Delhi Power Limited (NDPL) is a joint venture between Tata Power Company and the Government of NCT of Delhi with the majority stake being held by Tata Power. It distributes electricity in North & North West parts of Delhi and serves a populace of 50 lakh . The company started operations on July 1, 2002 post the unbundling of erstwhile Delhi Vidyut Board. With a registered consumer base of around 10 lakh and a peak load of around 1180 MW, the company’s operations span across an area of 510 sq kms.  NDPL has been the frontrunner in implementing power distribution reforms in the capital city and is acknowledged for its consumer friendly practices. Since privatisation, the Aggregate Technical & Commercial (AT&C) losses in NDPL areas have shown a record decline. Today they stand at 15% which is an unprecedented reduction of over 73% from an opening loss level of 53%.

On the power supply front too, NDPL areas have shown remarkable improvement. The company has embarked upon an ambitious plan to implement high-tech automated systems for its entire distribution network. Systems such as SCADA, GIS and OTS are the cornerstone of the company’s distribution automation project. To fight the menace of power theft, modern techniques like High Voltage Distribution (HVDS) System and LT Arial Bunch Conductor have been adopted.

NDPL has to its credit several firsts in Delhi: SCADA controlled Grid Stations, Automatic Meter Reading, GSM based Street Lighting system and SMS based Fault Management System. To ensure complete transparency, the company has provided online information on billing and payment to all its 1 million consumers. This happened in the first year of operations itself. NDPL believes in providing more value than just electricity and is even rewarding its consumers for timely payment.    

NDPL is the first power distribution utility from India to have won the prestigious Edison Award in the international category. The prestigious award is given annually by the Edison Electric Institute (EEI) to honour both international and U.S. electric companies for outstanding contributions to the advancement of the Power industry.

NDPL was also conferred the ‘Asian Utility of the Year 2008’ award by Asian Power and is also the winner of Palladium Balanced Scorecard Hall of Fame Award.

NDPL has the distinction of being the youngest company and the first power utility in India to receive the prestigious CII EXIM Award for ‘Strong Commitment to Excel’. It is also the only distribution utility to receive the ISO 9001, ISO 14001 and OHSAS 18001 certification. NDPL has also been conferred the ‘National Award for Meritorious Performance’ by the President of India.

BUSINESS GROUP DEVELOPMENT

With a view to leverage on NDPL’s domain expertise and with an objective of providing end to end solutions to power utilities, NDPL Business Development Group has been constituted. The Group draws experience from some of the best known names in the Indian Power Sector fraternity, who have played a major role in their respective fields, contributing to NDPL’s success.

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Our core competence lies in conceptualizing workable solutions and delivering immediate to long term sustainable results.

Projects Undertaken so far during few years:

Consultancy Services for Loss Reduction for Public Electricity Corporation, Republic of Yemen Ministry of Electricity and Energy. Under execution

Establishing Monitoring & Evaluation framework for agricultural consumption in Haryana  for Haryana Distribution Companies (DHBVN & UHBVN) - Under execution

Diagnostic study of DHBVN, Haryana with reference to Energy Audit and Load Management Practices (World Bank Funded) – currently in execution in association with TCS

Development of Call Center and Consumer Care Centre, Paschimanchal Vidyut Vitran Nigam Limited (PVVNL – Noida Circle)

Advisory Support for restructuring of Transmission & Distribution Function for Central Electricity Board (CEB), Mauritius

Implementation of the Corporate Restructuring of Nigeria Electricity Power Authority (NEPA), now PHCN (Power Holding Company of Nigeria)

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NDPL has been empanelled as IT Consultant with Power Finance Corporation for R-APDRP

NDPL has been also empanelled as IT Implementation agency with Power Finance Corporation for R-APDRP for all the four (4) roles (System Integrator, GIS Service Provider, Network Service Provider and Meter Data Acquisition

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POLICY FRAMEWORK AND POLICIES

Electricity as a subject is in the concurrent list of constitution of India. It means that both the Union and the State Governments can formulate policies and laws on the subject but the responsibility of implementation rests with the states. Distribution of electricity in particular comes in the domain of the states.

In India, Legal provisions to support and regulate the sector were put in place through the Indian Electricity Act, 1910. Shortly after independence, a second Act - The Electricity (Supply) Act, 1948 was formulated, paving the way for establishing Electricity Boards in the states of the Union. The third act in place was Electricity Regulatory Commission Act, 1998 which had established the regulatory commissions which continued under the new act called Electricity Act 2003.

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SUSTAINABILITY

Community welfare is central to the core values of NDPL and  serves as one of the major purposes of our existence. The concern for bringing  about a positive change in people’s lives drives us as a company. Our motto  ‘Power to the people’ not only translates to offering business services, but  attempts to empower the society at large as well.

Our commitment to the community’s welfare is exemplified through  a part of our Mission statement - ‘to enrich quality of life in the society that  we operate in’ and this is the foundation of the Company’s operations. NDPL  believes believe that serving the community helps us achieve a higher corporate  purpose.  As responsible corporate  citizens we:

  Devise  strategies that aim at deploying technology, products and services

to help  generate sustainable livelihoods for the underprivileged   Voluntarily  serve communities around us better the lives of people here.  Employ the  physically challenged and make them a part of our workforce

and ensure a congenial  work environment for them.   Endeavour to  offer solutions to the challenges of globalization by

becoming a signatory to  the Global Compact (from Sept ’05).   Empower  deprived children with education and initiate adult literacy

programmes.

NDPL  is also a signatory to the UN Global Compact Charter and is now part of an  elite group of 1200 organisations the world over. These organisations have  committed themselves to the areas of human rights, labour, environment and anti  corruption, as outlined in the charter.  

In order to assure humane workplaces for employees and associates engaged by its business associates, NDPL also initiated the implementation of SA 8000-2008 in October -08 and the certification and assessment is expected by July/August 2009.

The SA-8000 standard and verification system is a credible, comprehensive and efficient tool for assuring humane workplaces. It includes: workplace management systems requirements; independent, expert verification of compliance; involvement by all stakeholders; and public reporting. SA8000 is based on international workplace norms, including 12 International Labour Organization (ILO) conventions and the United Nations’ Universal Declaration of Human Rights, the Convention on the Rights of the Child and the Convention to Eliminate All Forms of Discrimination against Women.

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AWARDS AND RECOGNITION

1. NDPL Wins  Best Revenue Assurance Initiative (Metering Award)  for 2008.

NDPL bagged ‘Best Revenue Assurance Initiative’ (Metering Award) for 2008 organized by Utility Planning Network Global AMI Utility Peer Group. NDPL has been awarded for its Revenue Generation Initiative.

Utility Planning Network (UPN) is a unique peer groups which networks professionals who manage energy decision in large commercial and industrial corporations. It is a unique award as the awardees are selected based on judging by utility peers across the world. The winners for the awards were selected amongst utilities from Europe, Asia, Africa, Australia, The United States and Canada.

2. National Award to NDPL for Meritorious Performance in Power Distribution

NDPL has been awarded the prestigious ‘National Award for Meritorious Performance’ in Power Distribution by the Hon’ble President of India Smt Pratibha Devisingh Patil. The award, instituted by the Ministry of Power, Government of India, was conferred in recognition of NDPL’s outstanding performance in power distribution.

3. Enertia Awards 2008

NDPL won Enertia Awards 2008- Best Urban Utility for Adoption of Best Performance-Consumer Friendly Practices and e-governance.

4. Amity Leadership Award for Sectoral Excellence in Energy Sector

NDPL has been awarded the ‘Amity Leadership Award 2008’ for Sectoral Excellence in the Energy Sector. The award was conferred on 17th October, 2008 during the 4th Global Leadership Submit at Amity University Campus at NOIDA, by Shri Digvijay Singh, Ex- Chief Minister – Madhya Pradesh and Dr. Ashok K. Chauhan, founder President, Amity University.

5. NDPL Wins 'India Power Awards 2008' - Adjudged winner in recognition for 'Overall Utility Performance in Distribution'

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North Delhi Power Limited (NDPL) won 'India Power Awards 2008' in recognition for Overall Utility Performance in Distribution.

6. NDPL Wins 'Asian Utility of the Year Award 2008' at Asian Power Awards

NDPL has won the 'Asian Utility of the Year 2008' award at the recently held 'Asian Power Awards 2008'. Mr. Sunil Wadhwa, Chief Executive Officer, NDPL, has been conferred the prestigious 'Most Inspirational CEO of the Year' award.

7. NDPL wins International Balanced Scorecard (BSC) Hall of Fame Award 2008

NDPL has won the international Palladium Balanced Scorecard Hall of Fame award- 2008. The award puts NDPL in a select and elite group of 106 companies worldwide who have won the award. NDPL deployed the Balanced Scorecard (BSC) as a tool for strategy execution and used it to transform itself to a consumer centric entity with a performance-driven culture.

8 . NDPL Wins 'SAP ACE Award 2008'

NDPL won SAP ACE Award 2008 in the category "Best Utilities Sector Implementation - Large Enterprises". In its third edition, the SAP ACE awards 2008 celebrates breakthrough IT deployment catalyzing business transformation.

9. NDPL Wins Prestigious Honour- The Edison Award by Edison Electric Institute (EEI), USA.

North Delhi Power Limited has become the first power distribution utility from India to have received the prestigious honor in the international category by winning the Edison Award.

The award was presented to NDPL, in recognition of its operational excellence in the electric industry, for innovatively utilizing and integrating its Geographical Information System (GIS) with other applications for network planning, operations, commercial and asset management.

The prestigious award is given annually by the Edison Electric Institute (EEI) to honour both international and U.S. electric companies for outstanding contributions to the advancement of the Power industry. A panel of academics and past and current EEI Chairmen select the finalists and ultimate winners.

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10. 'Excellence in Cost Management 2007' Award by ICWAI.

NDPL won the 'National Award for Excellence in Cost management' in the category of "Service Sector with turnover of more than 1000 Crores" by the Institute of Cost & Works Accountants of India (ICWAI). This is for the first time in India that any electricity distribution company has been conferred an award for cost management initiatives.

NDPL has been acknowledged for its sincere efforts in increasing revenue through reduction in AT&C losses over a period of more than 5 years through constant endeavor of cost management practices in all spheres in a regulatory regime.

11. 'Power Utility of the Year' Award at Asian Power Awards 2007

North Delhi Power Limited (NDPL) has won the 'Power Utility of the Year' award at 'Asian Power Awards 2007'. Asian Power Awards are the industry's leading awards independently judging the best in the power industry in entire Asia. There are total of 25 awards of which ten go to power plants and the rest to companies and projects. The awards are aimed at recognizing the broad spectrum of Asia's power supply industry and acknowledging the vital input from all elements of this industry.

12. 'Most Admired Organization in the Joint Sector/Private Sector' award

North Delhi Power Limited (NDPL) has been presented the Power Line 'Expert Choice Awards' for the 'Most Admired Organization in the Joint Sector/ Private Sector'. The awards were given by Mr Sushil Kumar Shinde, Union Minister of Power.The awards are based on a first of its kind 'Eminent Expert Opinion Survey' by Power Line, a premier magazine for the Indian power sector, in which sector specialists were asked to give their opinion on various criteria pertaining to Power sector.

13.Asian Power Award 2006 for Excellence in Service Enhancement

NDPL has won Asian Power Awards 2006 for Excellence in Service Enhancement. Asian Power Awards are the industry's leading awards independently judging the best in the power industry in entire Asia. There are total of 25 awards of which ten go to power plants and the rest to companies and projects. The awards are aimed at recognizing the broad spectrum of Asia's power supply industry and acknowledging the vital input from all elements of this industry. The award conferred on NDPL is in recognition to its outstanding achievement throughout the year and fortifies it status as a leader in the power industry.

14.Achievers Award for settling 10,000 cases in record time

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NDPL has successfully settled 10,000 cases in PLAs, Special Lok Adalats under the aegis of DLSA during the period October 2003- July 2006. The award was presented to NDPL by the Hon'ble Chief Justice Delhi High Court for this landmark achievement. It is record in the history of Alternate Disputes Resolution (ADR) Mechanism (under the Legal Services Authority Act, 1987).

15.TBEM Score Band 551-650

It is a matter of joy and pride that in TBEM External Assessment 2008, NDPL has moved from previous score band of 451-550 to the upper band of 551-650, which distinguishes us as 'Emerging Industry Leader'. The TBEM Excellence framework is practiced in almost all TATA organization and is based on the renowned Malcolm Baldridge Award Instituted in the United States.

16. CII EXIM AWARD for Strong Commitment to Excel

NDPL is the youngest and only Power Distribution utility in India to have been bestowed with this prestigious award for exhibiting strong commitment to excel.

17. ISO 9001, ISO 14001 and OHSAS 18001

NDPL is a certified ISO 9001, ISO 14001 and OHSAS 18001 company which bears testimony to its commitment to Quality, Environment Management & Safety related aspects of Power Distribution.

18.NABL Accreditation for NDPL's Meter Testing Lab

NDPL became the 1st power utility in Northern India to receive accreditation for it's state-of-the art meter testing lab from NABL (National Accreditation Board for Testing and Calibration Laboratories). NABL is an autonomous body established under the aegis of Department of Science & Technology, Government of India. The accreditation signifies that the applied testing results of NDPL's Lab are legally valid and at par with test results of any laboratory across the globe.

19. Intelligent Enterprise Award

NDPL's billing system and other consumer friendly IT interventions have made us achieve the Intelligent Enterprise Award instituted by the Indian Express Group two years in succession.

20.Annual Bhagidari Award for 'Outstanding Work in Promoting Bhagidari Initiative' for the year 2006-07

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NDPL won the Annual Bhagidari Award for 'Outstanding Work in Promoting Bhagidari Initiative' for the year 2006-07. Smt.Sheila Dikshit, Hon'ble Chief Minister of Government of Delhi, presented the award to Team NDPL at the awards ceremony in the 'Bhagidari Utsav 2007' organized at Pragati Maidan on February 2nd & 3rd, 2007 by the Government of Delhi.

21.National Award to NDPL for Meritorious Performance in Power Distribution

NDPL was awarded the prestigious silver 'National Award for Meritorious Performance for 2004-2005 & 2005-2006' in Power Distribution by the Hon'ble Prime Minister of India Dr. Man Mohan Singh.

The award, instituted by Ministry of Power, Government of India, was conferred in recognition of NDPL's outstanding performance in power distribution.

22. 'PCQuest Best Information Technology (IT) Implementation Award 2007'

NDPL won the PC Quest Best IT Implementation Award for successful implementation of GIS (Graphical Information System) in its distribution network of North & North West Delhi. NDPL was awarded the most challenging project award.

The usage of GIS by NDPL has been touted as an innovative use of IT wherein it has created a GIS map of North Delhi and has captured every detail down to the last street along with each and every piece of electrical equipment including grids, transformers, wires etc in it's electricity distribution area.

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INTRODUCTION TO TRANSFORMERS

Transformer

A transformer is a device that transfers electrical energy from one circuit to another through inductively coupled conductors — the transformer's coils. A varying current in the first or primary winding creates a varying magnetic field through the secondary winding. This varying magnetic field induces a varying electromotive force (EMF) or "voltage" in the "secondary" winding. This effect is called mutual induction.

If a load is connected to the secondary, an electric current will flow in the secondary winding and electrical energy will be transferred from the primary circuit through the transformer to the load. In an ideal transformer, the induced voltage in the secondary winding (VS) is in proportion to the primary voltage (VP), and is given by the ratio of the number of turns in the secondary (NS) to the number of turns in the primary (NP) as follows:

By appropriate selection of the ratio of turns, a transformer thus allows an alternating current (AC) voltage to be "stepped up" by making NS greater than NP, or "stepped down" by making NS less than NP.

In the vast majority of transformers, the coils are wound around a ferromagnetic core, air-core transformers being a notable exception.

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Transformers come in a range of sizes from a thumbnail-sized coupling transformer hidden inside a stage microphone to huge units weighing hundreds of tons used to interconnect portions of national power grids. All operate with the same basic principles, although the range of designs is wide. While new technologies have eliminated the need for transformers in some electronic circuits, transformers are still found in nearly all electronic devices designed for household ("mains") voltage. Transformers are essential for high voltage power transmission, which makes long distance transmission economically practical.

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CHAPTER: 1

DISTRIBUTION TRANSFORMERS

Distribution transformers are pole-type transformers that supply relatively small amounts of power to residences. They are used at the end of an electrical utility’s delivery system. Both single-phase and three-phase products are available. Performance specifications for distribution transformers include primary frequency and maximum primary voltage rating. The primary frequency is measured in Hertz (Hz) and indicates the frequency of incoming voltage signals to primaries. Choices include 50 Hz, 60 Hz, 50 and 60 Hz, and 400 Hz. Typically, 400 Hz distribution transformers are designed for aerospace and military applications. Products with other frequency options may also be available. The maximum primary voltage rating is measured in volts (V) and represents a maximum value for devices that use several nominal voltages.

For distribution transformers with a single-phase primary configuration, size and cost increases with the number of leads. Devices with only one winding in the primary side can accept one nominal voltage. Conversely, devices with two primary-side windings can accept two nominal voltages. Single-phase distribution transformers that use the quad (2+2) configuration have dual windings in the primary side where each winding has a tap that can accept two nominal voltages. Devices with 5-lead voltage selectors can accept five possible nominal voltages. Distribution transformers with a ladder configuration consist of windings in a cascade, and a series of inductances connected between adjacent windings. As a rule, a ladder is the least economical primary configuration.

Three-phase distribution transformers are connected in delta or wye configurations. A wye - delta distribution transformer has a primary winding connected in a wye (Y) and a secondary winding connected in a delta. A delta - wye distribution transformer has a primary winding connected in a delta and a secondary winding connected in a wye. Choices for three-phase distribution transformers include delta - delta, delta - wye, wye - wye, wye - delta, wye - single phase, delta - single phase, and international. International transformers are fully compliant with both U.S. and international standards from organization such as the International Electrotechnical Commission (IEC) and the National Electrical Manufacturer’s Association (NEMA). International distribution transformers can be used in the U.S or in any country that supports their voltage and frequency requirements.

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CHAPTER : 2

POWER TRANSFORMERS

Power transformers

Laminated core

This is the most common type of transformer, widely used in appliances to convert mains voltage to low voltage to power electronics

Widely available in power ratings ranging from mW to MW Insulated laminations minimize eddy current losses Small appliance and electronic transformers may use a split bobbin, giving a high

level of insulation between the windings Rectangular core Core laminate stampings are usually in EI shape pairs. Other shape pairs are

sometimes used. Mumetal shields can be fitted to reduce EMI (electromagnetic interference) A screen winding is occasionally used between the 2 power windings Small appliance and electronics transformers may have a thermal cut out built in Occasionally seen in low profile format for use in restricted spaces laminated core made with silicon steel with high permeability

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Toroidal

Doughnut shaped toroidal transformers are used to save space compared to EI cores, and sometimes to reduce external magnetic field. These use a ring shaped core, copper windings wrapped round this ring (and thus threaded through the ring during winding), and tape for insulation.

Toroidals compared to EI core transformers:

Lower external magnetic field Smaller for a given power rating Higher cost in most cases, as winding requires more complex & slower equipment Less robust Central fixing is either

o bolt, large metal washers & rubber padso bolt & potting resin

Overtightening the central fixing bolt may short the windings greater inrush current at switch-on. Autotransformer

Autotransformer

An autotransformer has only a single winding, which is tapped at some point along the winding. AC or pulsed voltage is applied across a portion of the winding, and a higher (or lower) voltage is produced across another portion of the same winding. The higher voltage will be connected to the ends of the winding, and the lower voltage from one end to a tap. For example, a transformer with a tap at the center of the winding can be used with 230 volts across the entire winding, and 115 volts between one end and the tap. It can be connected to a 230-volt supply to drive 115-volt equipment, or reversed to drive 230-volt equipment from 115 volts. Since the current in the windings is lower, the transformer is smaller, lighter cheaper and more efficient. For voltage ratios not

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exceeding about 3:1, an autotransformer is cheaper, lighter, smaller and more efficient than an isolating (two-winding) transformer of the same rating. Large three-phase autotransformers are used in electric power distribution systems, for example, to interconnect 33 kV and 66 kV sub-transmission networks.

In practice, transformer losses mean that autotransformers are not perfectly reversible; one designed for stepping down a voltage will deliver slightly less voltage than required if used to step up. The difference is usually slight enough to allow reversal where the actual voltage level is not critical. This is true of isolated winding transformers too.

Variac

By exposing part of the winding coils of an autotransformer, and making the secondary connection through a sliding carbon brush, an autotransformer with a near-continuously variable turns ratio can be obtained, allowing for wide voltage adjustment in very small increments.

Stray field transformer

A Stray field transformer has a significant stray field or a (sometimes adjustable) magnetic bypass in its core. It can act as a transformer with inherent current limitation due to its lower tight coupling between the primary and the secondary winding, which is unwanted in much other cases. The output and input currents are low enough to prevent thermal overload under each load condition - even if the secondary is shortened.

Stray field transformers are used for arc welding and high voltage discharge lamps (cold cathode fluorescent lamps, series connected up to 7,5 kV AC working voltage). It acts both as voltage transformer and magnetic ballast.

Polyphase transformers

For three-phase power, three separate single-phase transformers can be used, or all three phases can be connected to a single polyphase transformer. The three primary windings are connected together and the three secondary windings are connected together. The most common connections are Y-Delta, Delta-Y, Delta-Delta and Y-Y. A vector group indicates the configuration of the windings and the phase angle difference between them. If a winding is connected to earth (grounded), the earth connection point is usually the center point of a Y winding. If the secondary is a Delta winding, the ground may be connected to a center tap on one winding (high leg delta) or one phase may be grounded (corner grounded delta). A special purpose polyphase transformer is the zigzag transformer. There are many possible configurations that may involve more or fewer than six windings and various tap connections.

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Example of Y Y Connection

Resonant transformers

A 25 kV flyback transformer being used to generate an arc.

A resonant transformer operates at the resonant frequency of one or more of its coils and (usually) an external capacitor. The resonant coil, usually the secondary, acts as an inductor, and is connected in series with a capacitor. When the primary coil is driven by a periodic source of alternating current, such as a square or sawtooth wave at the resonant frequency, each pulse of current helps to build up an oscillation in the secondary coil. Due to resonance, a very high voltage can develop across the secondary, until it is limited by some process such as electrical breakdown. These devices are used to generate high alternating voltages, and the current available can be much larger than that from electrostatic machines such as the Van de Graaff generator or Wimshurst machine.

Examples:

Tesla coil Oudin coil (or Oudin resonator; named after its inventor Paul Oudin) D'Arsonval apparatus Ignition coil or induction coil used in the ignition system of a petrol engine Flyback transformer of a CRT television set or video monitor. Electrical breakdown and insulation testing of high voltage equipment and cables.

In the latter case, the transformer's secondary is resonated with the cable's capacitance.

Other applications of resonant transformers are as coupling between stages of a superheterodyne receiver, where the selectivity of the receiver is provided by the tuned transformers of the intermediate-frequency amplifiers.

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Constant voltage transformer

By arranging particular magnetic properties of a transformer core, and installing a ferro-resonant tank circuit (a capacitor and an additional winding), a transformer can be arranged to automatically keep the secondary winding voltage relatively constant for varying primary supply without additional circuitry or manual adjustment. CVA transformers run hotter than standard power transformers, because regulating action depends on core saturation, which reduces efficiency somewhat. The output waveform is heavily distorted unless careful measures are taken to prevent this. Saturating transformers provide a simple rugged method to stabilize an AC power supply.

Ferrite Core

Ferrite core power transformers are widely used in switched mode power supplies (SMPSUs). The powder core enables high frequency operation, and hence much smaller size to power ratio than laminated iron transformers.

Ferrite transformers are not usable as power transformers at mains frequency.

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CHAPTER : 3

TIPS FOR SAVING ENERGY

1. Turn off your home office equipment when not in use. A computer that runs 24 hours a day, for instance, uses - more power than an energy-efficient refrigerator.

2. If your computer must be left on, turn off the monitor; this device alone uses more than half the system's energy.

3. Setting computers, monitors, and copiers to use sleep-mode when not in use helps cut energy costs by approximately 40%.

4. Battery chargers, such as those for laptops, cell phones and digital cameras, draw power whenever they are plugged in and are very inefficient. Pull the plug and save

5. Screen savers save computer screens, not energy. Start-ups and shutdowns do not use any extra energy, nor are they hard on your computer components. In fact, shutting computers down when you are finished using them actually reduces system wear - and saves energy.

6. One of the best energy-saving devices is the light switch. Turn off lights when not required.

7. Dirty tube lights and bulbs less light and can absorb 50 percent of the light; dust your tube lights and lamps regularly.

8. Fluorescent tube lights and CFLs convert electricity to visible light up to 5 times more efficiently than ordinary bulbs and thus save about 70% of electricity for the same lighting levels.

9. Ninety percent of the energy consumed by an ordinary bulb (incandescent lamp) is given off as heat rather than visible light.

10.A 15-watt compact fluorescent bulb produces the same amount of light as a 60-watt incandescent bulb

11.By reducing the temperature setting of water heater from 60 degrees to 50 degrees C, one could save over 18 percent of the energy used at the higher setting.

12.To help reduce heat loss, always insulate hot water pipes, especially where they run through unheated areas. Never insulate plastic pipes.

13.Use an electric kettle to heat water. It's more energy efficient than using an electric cook top element.

14.Iron your clothes and linen all in one go. Do not keep a hot iron which is switched in an upright position for long period since more heat will be lost

15.Avoid storing hot / warm food in the refrigerator

16.Use of white or light colours for interior walls, ceilings, curtains, drapes and furniture reflects more light within the building and therefore further reduces the cost of lighting.

17.Do not set the temperature regulator of the refrigerator at high if the quantity of the food within is small. Also, stack food items inside to allow air circulation.

18.By locating doors and windows to admit more sunlight through them you can avoid using electricity for lighting your home or office during the day.

19.Orientation of the house and surrounding landscape has a large effect on energy consumption. Planting trees on the south and west will reflect natural light through the windows resulting in less use of heating appliances like room heaters etc. in winters and would provide ample light.

20.Auto defrost refrigerators consume more electricity. Larger the refrigerator, higher will be the usage of electricity

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CHAPTER:4

FREQUENTLY ASKED QUESTIONS

Q. Does internal wiring needs to be checked on installation of new electronic meter?

A. All consumers where NDPL has already installed new Electronic Meters are advised to get their wiring checked for Earth Leakage and Intermixing of wiring (phase, neutrals) between two or more metered connections.

NDPL would hereinafter check wiring status for any intermixing, earth leakage and connected load, before replacement and installation of new electronic meters and inform consumers the status on the date of checking. It is however essential that the consumers maintain the internal wiring in good and correct condition at all times for their own safety. The Indian Electricity Rules 1956 also require that no electrical installation work (including additions, alternations, repairs and adjustments to existing installation), except replacements of lamps, fans, fuses, switches, low voltage domestic appliances and fitting do not alter the capacity and the character of the installations carried out upon the premises on behalf of any consumer or owner for the purposes of supply, except by qualified personnel. NDPL has trained such of the neighborhood electricians who volunteered themselves and the list, contact details of such electricians is placed on NDPL web site.

Q. Is it important to install Earth Leakage Circuit Breaker?

A. Yes, With a view to protecting the internal wiring within consumer premises as also for safety of inmates, appliances, NDPL recommends use of Earth Leakage Circuit Breakers (ELCB) as main switch immediately after the Meter. This is designed to protect internal wiring as also securitize for all times against any Earth Leakage or Wiring errors, wrong interconnections, leakages that may arise within consumer premises. Use of ELCB's is also statutory for premises with loads equal to above 5 KW.

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CHAPTER : 5

ENERGY AWARENESS

In times as now, when the world is moving towards an impending energy crisis, promoting public understanding and awareness about different kinds of energy generation, dissemination and their consumption has become important. While the nation’s appetite for electricity consumption is growing at a steady rate, the resources are getting scarce every day. In the wake of this crisis, it becomes essential to educate consumers about energy and its rightful usage, and the necessary steps that consumers should take to reduce their demand for electricity as well as their sky-high energy bills.

Because of the limited amount of nonrenewable energy sources on Earth, it is important to conserve our current supply or to use renewable sources so that our natural resources will be available for future generations. Energy conservation is also important because consumption of nonrenewable sources impacts the environment. Specifically, our use of fossil fuels contributes to air and water pollution. For example, carbon dioxide is produced when oil, coal, and gas combust in power stations, heating systems, and car engines. Carbon dioxide in the atmosphere acts as a transparent blanket that contributes to the global warming of the earth, or 'greenhouse effect.' It is possible that this warming trend could significantly alter the climate. Possible impacts include a threat to human health, environmental impacts such as rising sea levels that can damage coastal areas, and major changes in vegetation growth patterns that could cause some plant and animal species to become extinct.

Indian Electricity Sector provides enormous opportunities for energy service companies and also for those who manufacture energy efficient equipments, gadgets and devices. It has been established that energy efficiency projects, when appropriately implemented, could lead to a saving of as much as 23% of energy consumption.