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...MINISTRY OF POWER AND MINERAL RESOURCES OF THE REPUBLIC OF KAZAKHSTAN APPROVED by Prikaz No 189 of the Minister of Power and Mineral Resources of the Republic of Kazakhstan, as of August 26, 2004.) REGULATIONS ON ELECTRICAL INSTALLATIONS OF THE REPUBLIC OF KAZAKHSTAN (PUE) Astana, 2003 TABLE OF CONTENTS SECTION 1: GENERAL REGULATIONS 10 CHAPTER 1.1: GENERAL 10 SCOPE, TERMS AND DEFINITIONS 10 GENERAL REGULATIONS FOR INSTALLATION OF ELECTRICAL EQUIPMENT 11 CONNECTION OF ELECTRICAL INSTALLATIONS TO THE POWER STATIONS 13 COMMISSIONING OF ELECTRICAL INSTALLATIONS 14 CHAPTER 1.2 POWER SUPPLY AND POWER SYSTEMS 14 SCOPE, DEFINITIONS 14 GENERAL REQUIREMENTS 14 CATEGORIES OF POWER CONSUMING DEVICES AND RELIABILITY OF POWER SUPPLY 15 VOLTAGE LEVELS AND CONTROLS, REACTIVE POWER COMPENSATION 16 CHAPTER 1.3 SELECTION OF CONDUCTORS: HEATING, CURRENT DENSITY AND CORONA DISCHARGE CONDITIONS 16 SCOPE 16 SELECTION OF CROSS-SECTION OF CONDUCTORS: HEATING 17 MAXUIMUM CONTINUOUS CURRENTS FOR WIRES, CORDS AND CABLES IN RUBBER OR PLASTIC INSULATION 18 MAXIMUM CONTINUOUS CURRENTS FOR CABLES IN IMPREGNATED PAPER INSULATION 22 MAXIMUM CONTINUOUS CURRENTS FOR BARE......
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...CHAPTER-1 Dhaka Electric Supply Company Limited (DESCO) overview After the creation of an independent Bangladesh, in 1972, the first Government of Bangladesh, in an effort to speed up the investment in the sector issued an Ordinance creating the Bangladesh Power Development Board (BPDB) as the successor organization of the power side of EWAPDA. The Ordinance recognized the divergence of energy related issues in development. During 1972 to 1995, BPDB has increased the generating capacity in the country to 2818 MW, and the length of its 230 and 132 KV transmission networks to 419 KM and 2469 KM. For the first time in December 1982, the eastern and western halves of the country were electrically connected through the commissioning of double circuit 230 KV transmission line across the Jamuna riever energized at 132 KV between Ishurdi and Tongi called the first East-West Interconnector. Generation sources were diversified to include a 230 MW hydropower station at Kaptai on the Karnaphuli river and natural gas and imported fuel based, open and combined cycle power plants at different locations of Eastern and Western part of the country. The distribution networks of all major towns and cities had been linked through 230 KV and 132 KV inter-ties. In 1990, government issued an ordinance, which was subsequently enacted as an Act transferring the 132 kv, 33 kv Transmission and distribution system in the Greater Dhaka Area including the Metropolitan City to a newly created......
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...Over the next decade, the most vibrant Wireless Power Transmission (WPT) markets will involve the contactless charging of portable and mobile equipment, in particular consumer electronics and electric vehicles. Today, development teams worldwide are stretching the boundaries of physics using available components to create systems that are able to compete with the efficiencies of wired solutions while offering the conveniences of wire free connections. In the 1890's famous scientist and engineer Nikola Tesla dreamt of wireless transfer of power. He envisioned a world, in which all electricity is transferred wirelessly, but the idea was more or less abandoned and highly efficient copper cables became the basis for modern electricity infrastructure. Then, a few years ago, Marin Soljačić, an assistant professor of physics at MIT, was dragged out of bed by the insistent beeping of a cell phone. In his exhausted state, he wished the phone would just begin charging itself as soon as it was brought into the house. So, Soljačić started searching for ways to transmit power wirelessly. Soljačić found magnetic resonance a promising means of electricity transfer because magnetic fields travel freely through air yet have little effect on the environment or, at the appropriate frequencies, on living beings. Working with MIT physics professors John Joannopoulos and Peter Fisher and three students, he devised a simple setup that wirelessly powered a 60-watt light bulb. The MIT work has......
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...because of the fact that it is an electric field that goes directly into the light and doesn't use the electrodes; even burned-out florescent lights will glow. The significant part of our proposed plan is that power is transferred wirelessly. The field produced is without any radiations and hence is harmless to human beings. I. Introduction Nikola Tesla invented the Tesla Coil, a type of air-cored resonant transformer, which is used to generate high voltage and high frequency electrical currents. Tesla coils are used to produce high-voltage, low-current, and high-frequency alternating-current. It can produce higher voltages than other artificial sources of high-voltage discharges and electrostatic machines. It takes the output from a 230vAC to several kilovolt transformer & driver circuit and steps it up to an extremely high voltage. II. Basic Scheme of Tesla Coil A Tesla coil is a resonant transformer containing a primary and a secondary LC circuit. The two LC circuits are loosely coupled together. Power is supplied to the primary circuit through a transformer, which charges a capacitor. If the voltage in the capacitor is extremely high, the air resistance between the spark gap drops quickly and now the spark gap becomes a good conductor. The capacitor will discharge through...
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... Using Superposition Theorem, 3V source is removed to calculate the contribution of the 8 V supply. Similarly, 8V source is removed to calculate currents due to 3V supply. a) Voltage across the 18 ohm resistor is 4.6872 volts and current across is 0.2604 amperes; b)Current in the 8V generator is 1.667 amperes; c) Current in the 3V generator is 0.656 amperes. (John, 2003) Question 1.3 a) Transformers are electrical devices that play a very vital and key role in electrical power distribution and transmission systems. They are static devices, that is, they do not have any moving components. Transformers utilize one of the most basic forces in nature, the electromagnetic force to convert alternating electrical energy of one power rating to another power rating, but do not change the frequency of the primary electrical energy. Voltage transformers are used to lower or raise the magnitude of the incoming voltage and accordingly current increases or decreases. Electromagnetic induction is used to perform this conversion, more specifically mutual induction. In a simple voltage transformer, two coils are present that have common magnetic flux in between them but are electrically isolated. This path of magnetic flux has some magnetic reluctance that actually helps in power conversion. The core constitutes of laminated sheets around which the incoming voltage coils, also called the primary windings, and the outgoing voltage coils, also known as, secondary windings are wound. The......
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...LARGE POWER TRANSFORMERS AND THE U.S. ELECTRIC GRID Infrastructure Security and Energy Restoration Office of Electricity Delivery and Energy Reliability U.S. Department of Energy April 2014 Update Large Power Transformers and the U.S. Electric Grid This page intentionally left blank. DOE / OE / ISER April 2014 ii Large Power Transformers and the U.S. Electric Grid FOR FURTHER INFORMATION This report was prepared by the Office of Electricity Delivery and Energy Reliability under the direction of Patricia Hoffman, Assistant Secretary, and William Bryan, Deputy Assistant Secretary. Specific questions about information in this report may be directed to Dr. Kenneth Friedman, Senior Policy Advisor (kenneth.friedman@hq.doe.gov). Tiffany Y. Choi of ICF International contributed to this report. The U.S. Department of Energy would like to acknowledge the following reviewers for their contribution to this report: ABB American Transmission Company Bartley, William H., Hartford Steam Boiler Inspection and Insurance Company, A member of the Munich Reinsurance Company North American Electrical Reliability Corporation Ontario Power Generation Scott, Daniel U.S. Department of Commerce U.S. Department of Homeland Security U.S. Federal Energy Regulatory Commission Cover photo sources: Large power transformer photo: Siemens.com High-voltage transmission lines photo: Utilities-me.com DOE / OE / ISER April 2014 iii Large Power......
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...uninterrupted Power supply. NEHU Grid substation is connected to 4 Grid Substations namely Umiam Grid s/s by Umiam Feeder, Mawlai Grid S/s by Mawlai Feeder, NEIGRIHMS Grid S/s by NEIGRIHMS Feeder and Khliehriat S/s by Khliehriat Feeder which are further interconnected to other S/s and Power stations of the state of Meghalaya. The transmitting voltage is 132 KV. The Power received at NEHU S/s at 132 KV voltage level is transfer to the 33 KV Bus after the voltage is stepped down from 132 KV to 33 KV by 2 nos. 20 MVA transformer located in the 132 KV switchyard of the S/s. These two Transformers operate in parallel. From the 33 KV Bus the power is transfer to the different 33/11 KV sub-stations by the 33 KV Feeders viz, Happy Valley Feeder, Meter factory feeder, SE Falls Feeder, Umiam feeder and NEHU-Mawiong Feeder. There is also one 33 KV Tie-Line namely 33 KV Tie-Line-2 which connects the NEHU Grid S/s and Mawlai Grid S/s. This line facilitates the transformers at both Sub-stations to operate in parallel when the CBs and isolators of the line are closed at both ends. Some of the power received at NEHU S/s is consumed as energy in the Sub-station itself as station service for lighting, supply to the charging motors, Battery charger, cooling fans. etc. For this there is one 33/...
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...UNIT 2 D.C MACHINES 1. Give methods adopted to reduce the effect of armature reaction in a DC machine. i) By increasing the length of air gap at pole tips ii) By increasing the reluctance at pole tips iii) Providing compensating winding and interpoles. 2. List the advantages of lap winding in a DC machine. i) Reduction of weight of armature core ii) Cost of armature and field conductors iii) Overall length and diameter of machine. 3. State the relationship between number of armature coils and number of commutator segments in a dc machine. The relationship between number of armature coils and number of commutator segments in a dc machine is where - commutator segment pitch C- no. of coils D- diameter of commutator 4. State different losses in a dc generator. a) Copper losses: (i) armature copper loss (Ia2 Ra) ii) field copper loss (I2snRsh, I2seRse) b) Magnetic losses ( iron or core loss): i) hysteresis loss (Whα B1.6maxf) ii) eddy current loss(Weα B2maxf) iii) mechanical losses 5. What are the main dimensions of a rotating machine? The main dimensions of a rotating machine are armature diameter and stator core length. 6. Define specific magnetic loading. It is defined as the average flux density over the air gap of the machine. Specific magnetic loading = 7. Define specific electric loading. It is defined as the no of armature conductors per meter of armature periphery at the air gap. Specific electric loading = 8. What is output......
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...CHAPTER 2 BOOST CONVERTER 2.1 GENERAL A power converter with an output DC voltage greater than its input DC voltage is A step-up converter(boost converter). A class of SMPS(switching-mode power supply) containing semiconductor switches (a diode and a transistor). Filters made of capacitors to reduce output voltage ripple are normally added to the output of the converter . Fig. 2.1 Basic circuit of a boost converter using switch is typically a MOSFET, IGBT.[1] Power can also come from batteries, solar panels, rectifiers and DC generators. DC to DC conversion is a process that changes one DC voltage to a different DC voltage. A boost converter is called a step-up converter when it “steps up” the source voltage. power (P = VI) must be conserved so that output current is lower than the source current. 2.2 CIRCUIT ANALYSIS 2.2.1 Operating Principle: Fig 2.2.a illustrates the circuit action during the initial high period of the high frequency square wave applied to the MOSFET gate at start up. During this time MOSFET conducts, placing a short circuit from the right hand side of L1 to the negative input supply terminal. Therefore a current flows between the positive and negative supply terminals through L1, which stores energy in its magnetic field. There is virtually no current flowing in the remainder of the circuit as the combination of D1, C1 and the load represent a much higher impedance than the path directly through the heavily conducting MOSFET. Fig. 2.2 Boost......
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...Research Report 2005-27 Double Side Control of Wound Rotor Induction Machine for Wind Energy Application Employing Half Controlled Converters D. Panda, T. A. Lipo* Rockwell Automation Advanced Technology Lab, Richmond Heights, Ohio 44143, USA, dpanda@ieee. org *Department of Electrical and Computer Engineering University of Wisconsin, Madison, WI 53706, USA, lipo@engr.wisc.edu isconsin lectric achines & ower lectronics onsortium University of Wisconsin-Madison College of Engineering Wisconsin Power Electronics Research Center 2559D Engineering Hall 1415 Engineering Drive Madison WI 53706-1691 © 2005 Confidential Double side control of wound rotor induction machine for wind energy application employing half controlled converters Debiprasad Panda 1, Thomas .A.Lipo 2 Rockwell Automation Advanced Technology Lab, Richmond Heights, Ohio 44143, USA, dpanda@ieee.org 2 Department of Electrical and Computer Engineering University of Wisconsin, Madison, WI 53706, USA, lipo@engr.wisc.edu 1 Abstract – A double side converter fed wound rotor induction machine control for a wind energy application is proposed in this paper. In order to reduce the cost of a wind generator system, a new configuration using half controlled converters for both the stator and rotor circuit as well as for the line side is proposed. The proposed controller reduces the required KVA rating of both machine side and line side converters, improves the efficiency of the wind generator, helps......
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...Differentiating between market structures. Tiara Bingham ECO/365 11/26/2014 Al Gourrier Differentiating between market structures. There are certain factors that apply to all organizations. These factors are type of market structure, competitive strategies, customer base, and strengths and weaknesses. The success of a company depends upon these factors and if they format their business strategy to work within the different types of markets, if they can build upon their strengths and minimize their weaknesses, and provide the consumers with what they want. Market structures change depending on the condition of the market and the competition, in order for an organization to be successful, it has to be able to transform it business strategy to conform to market demands. Business strategies are decided after analyzing the market the company will compete in, competitors within that market and the consumer base. The organization that I chose to discuss is NV Energy. I will discuss the type of market that NV Energy operates in, why this market was chosen, How this company might work with other competitors in this market, and competitive strategies that could be used. NV Energy Nv Energy is the local power company established in Las Vegas Nevada. The type of market structure that Nv Energy operates in is called a Monopoly,in the case of NV Energy it is a public utility which is overseen by the government and allowed to operate as a monopoly. In a monopoly market......
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...Soitage ~GY ~OVU)~P December 18, 2008 Appendix A The 325kW (ac) solar photovoltaic (PV) power system located at Pilgrim Furniture City, 1755 Boston Post Road, Milford CT is interconnected to the local electrical distribution grid using a ‘behind the meter’ 480V 3 phase interconnection. As such, electricity that is generated by the solar PV system is used by the Pilgrim Furniture facility, effectively reducing the demand on the local electricity distribution grid. During periods when the solar PV system produces more electricity than is needed by the Pilgrim Furniture facility, the excess electricity is delivered back to the distribution grid via the utility company’s transformer. The solar PV system electrical layout and interconnection arrangement are detailed in the attached drawings. There are two solar PV inverters that control the electrical interconnection between the solar PV system and the local distribution grid. These are a Satcon 225kW inverter (model AE-225-60-PV-A) and a Satcon 100kW inverter (model AE-1 00-60-P V-A). These inverters are designed, manufactured and certified in full accordance with UL 1741. lnverter cutsheets are attached. The electricity production from the Solar PV system is measured by means of a revenuegrade metering system, this incorporating the following primary components: • Two “Shark 100” revenue-grade meters (manufactured by Electro Industries), with each meter measuring the electricity output from one of the......
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...Chapter 01 1.1 Introduction: A storage device may be used to store energy from renewable energy source in DC form which can be converted to AC power by using power inverter. Pulse Width Modulated (PWM) technique may be used to control output rms voltage of the inverter. As the load is variable, the power consumed by the load (PL) may be smaller than the power generated from the renewable energy source (PR). Therefore a Flexible AC Transmission System (FACTS) Controller may be used to supply the additional power (PR – PL) from the renewable energy source to the grid. On the other hand if the power consumed by the load (PL) is greater than the power generated from the renewable energy source (PR) therefore the same FACTS controller may be used to absorb the additional power (PR – PL) from the grid to the load. In this case the FACTS controller must allow bi-directional power flow. If all the active houses are connected to the grid in the same way (proposed way), the active houses that generate more power than the load can be supplied to the active houses that generate less power than the load. Therefore a suitable FACTS controller should be designed in such a way that it can control the power flow in both directions. The idea is illustrated in the following figure. 1.2 Objectives: • Study on different FACTS controllers • Study on different renewable energy sources • Study on......
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...TERM PAPER ON POWER FLOW MODEL OF SATCOM SUBMITTED TO- SUBMITTED BY- Md. Ibrahim bhat 11010038 INTRODUCTION In power engineering, the power flow study, also known as load-flow study, is an important tool involving numerical analysis applied to a power system. A power flow study usually uses simplified notation such as a one-line diagram and per-unit system, and focuses on various forms of AC power (i.e.: voltages, voltage angles, real power and reactive power). It analyzes the power systems in normal steady-state operation. A number of software implementations of power flow studies exist. In addition to a power flow study, sometimes called the base case, many software implementations perform other types of analysis, such as short-circuit fault analysis, stability studies (transient & steady-state), unit commitment and economic load dispatch analysis. In particular, some programs use linear programming to find the optimal power flow, the conditions which give the lowest cost per kilowatthour delivered. Power flow or load-flow studies are important for planning future expansion of power systems as well as in determining the best operation of existing systems. The principal information obtained from the......
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...MODERN PRACTICAL GUIDE ON ELECTRICAL MACHINES G.A.N BRIGHT REPORT PRESENTATION 1. Title 2. Aim 3. Apparatus/Equipments 4. Procedure/Method 5. Theory/Results 6. Safety Precaution 7. Conclusion N/B: Safety Precaution must be minimum of four PART 1 SYNCHRONOUS MACHINE 1.1 INTRODUCTION A synchronous machine is an a.c machine in which the rotor moves at a speed which bears a constant relationship to the frequency of currents, in the armature winding. A synchronous machine is one of the important type of electric machines. Large a.c networks operating at constant frequency of 50Hz rely almost exclusively on synchronous generators, also called the alternators, for the supply of electrical energy. Private, stand-by and peak load plants with diesel or gas-turbine prime movers also have synchronous generators. Synchronous motors provide constant speed industrial drives with the possibility of power factor correction. Synchronous machine are generally constructed in larger sizes. Small size alternators are not economical. The modern trend is to build alternators of very large size capable of generating 500MVA or even more. The synchronous motor is rarely built in small sizes owing to superior performance characteristics and economical construction of induction motors. 1.2 OPERATING PRINCIPLE The operating principle of a synchronous machine is fundamentally the same as that of a d.c machine, but,......
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