TRANSMISSION LINES DESIGN and ELECTRICAL ENGINEERING HUB

Grounding Transformers, also called Earthing Transformers, or Neutral Couplers are used to create a neutral point in a three phase system which provides possibility for neutral earthing. Grounding Transformers are used to provide a relatively low impedance path to ground. They also limit the magnitude of transient over voltages when re-striking ground faults occur. Grounding Transformers likewise provide a source of ground fault current during line to ground faults which. It permit the connection of phase to neutral loads is desired. Grounding Transformers can either be a transformer with just one winding that is zig zag connected, or a star/ delta connected winding. Grounding Transformer Specifications usually consist of the following paramaters: Primary Voltage - the system voltage to which the grounded winding is to be connected. Rated KVA - the grounding transformer must be sized to carry the rated continuous primary phase current without exceeding its temperature limit Conti...

The world's largest Nuclear Power Plant in terms of generated and rated capacity is Kashiwazaki-Kariwa power plant. It has a rated capacity of 8,212 megawatts, which provides more than 5 percent of Japan's total electricity. Kashiwazaki-Kariwa Power Plant Kashiwazaki-Kariwa is located in Japan and is and is owned by Tokyo Electric Power Company. It has a total area of is 4.2 kilometres square . It also includes land in the towns of Kashiwazaki and Kariwa in the Niigata Prefecture, Japan on the coast of the Sea of Japan, from where it gets cooling water. Kashiwazaki-KariwaIn was hit by an earthquake in 2007. This caused some damage and allowed a leak of a radioactive substance into the air and the water. The plant was subsequently closed and safety checks were completed. The plant was re-opened in May 2009. Other Information Regarding the Largest Nuclear Power Plant in the World Kashiwazaki-Kariwa Kashiwazaki-KariwaIn Nuclear Power Plant Built in Earthquake Fault Line The worl...

Nuclear power is energy that us produced thru controlled nuclear reaction, may it be nuclear fission or fusion. As of the moment, commercial and utility plants use nuclear fission reactions to heat water to produce steam, which is then used to generate electricity. Nuclear power and the operation of nuclear power plants work similarly with fossil fuel-burning stations, except that a "chain reaction" inside a nuclear reactor makes the heat instead. What's the Difference between Nuclear Fusion and Nuclear Fission Nuclear fusion and nuclear fission are two different types of energy-releasing reactions in which energy is released from high-powered atomic bonds between the particles within the nucleus. The main difference between these two processes is that fission is the splitting of an atom into two or more smaller ones while fusion is the fusing of two or more smaller atoms into a larger one. Continue Reading... Nuclear Power for Electrical Generation Nuclear power plant...

About Power Factor Low power factor is expensive and inefficient. Many utility companies charge you an additional fee if your power factor is less than 0.95. Low power factor also reduces your electrical system’s distribution capacity by increasing current flow and causing voltage drops. This fact sheet describes power factor and explains how you can improve your power factor to reduce electric bills and enhance your electrical system’s capacity. REDUCING POWER FACTOR COST To understand power factor, visualize a horse pulling a railroad car down a railroad track. Because the railroad ties are uneven, the horse must pull the car from the side of the track. The horse is pulling the railroad car at an angle to the direction of the car’s travel. The power required to move the car down the track is the working (real) power. The effort of the horse is the total (apparent) power. Because of the angle of the horse’s pull, not all of the horse’s effort is used to move the car down the track. Th...

Ungrounded or Isolated Neutral In an isolated neutral system, the neutral has no intentional connection to ground: the system is connected to ground through the line-to-ground capacitances. Single line-to-ground faults shift the system-neutral voltage but leave the phase-to-phase voltage triangle intact. For these systems, two major ground fault current magnitude-limiting factors are the zero sequence line-to-ground capacitance and fault resistance. Because the voltage triangle is relatively undisturbed, these systems can remain operational during sustained, low-magnitude faults. Self-extinction of ground faults in overhead-ungrounded lines is possible for low values of ground fault current. At higher magnitudes of fault current, faults are less likely to self extinguish at the fault current natural zero-crossing because of the high transient recovery voltage. Effective or Solid Grounding Effective, or solid, grounding is popular in the United States...

The X/R ratio is important because it determines the peak asymmetrical fault current. The asymmetrical fault current can be much larger than the symmetrical fault current.   In some short circuit studies, the X/R ratio is ignored when comparing the short circuit rating of the equipment to the available fault current at the equipment. What is not always realized is that when low voltage gear is tested, it is tested at a certain X/R ratio. Purpose of a Short Circuit Study The purpose of a short circuit study is to determine whether or not electrical equipment is rated properly for the maximum available fault current that the equipment may see. There are essentially four types of faults: three-phase single line-to-ground double line-to-ground line-to-line Each of these types of faults can result in different magnitudes of fault current. In all types, however, there is a common element: an abnormally low-impedance path for current to flow. Such a condition can lead to extremely high cu...

Power system harmonics are integer multiples of the fundamental power system frequency created by non-linear devices connected to the power system. High levels of power system harmonics can create voltage distortion and power quality problems. Harmonics in power systems result in increased heating in the equipment and conductors, misfiring in variable speed drives, and torque pulsations in motors. 1. The Effect of Harmonics on Electric Metering Power system harmonics distort the shape of the perfect voltage and current sinusoidal waveforms ideal to the power grid, and are multiples of the fundamental grid frequencies of 50 or 60 hertz found throughout the world. Problems caused by harmonics include overloaded circuits and higher system losses that can lead to premature equipment failure in utility and customer systems. Low utility power factor is generally associated with harmonics in electric metering. Read more on this link  http://www.ehow.com/about_6676198_effect-harm...

Practical Grounding, Bonding, Shielding and Surge Protection is a practical engineer's guide to the areas of grounding, shielding and surge protection designed to deliver reliable equipment and communications systems that comply with international and national codes. Practical Grounding, Bonding, Shielding and Surge Protection unlike many books on grounding and shielding, provides straight-forward, practical solutions to commonly encountered real-world situations and enables one to better understand proper ground methods and to quickly recognize and solve existing grounding issues in a facility. Also, it covers not only low voltage grounding techniques but also power system grounding, which is generally not well covered in literature. There are some very good examples illustrating how motor start-ups can induce a noise signal in signal cables through capacitive coupling into the conduit supplying the power to the motor. There are also many cases showing how ground loops ...

Electrical Power Cable Engineering, Second Edition remains the foremost reference on universally used low- and medium-voltage electrical power cables, cataloging technical characteristics and assuring success for cable manufacture, installation, operation, and maintenance. While segments on electrical cable insulation and field assessment have been revamped to reflect industry transformations, new chapters tackle distinctive topics like the location of underground system faults and the thermal resistivity of concrete, proving that this expanded edition lays the soundest foundation for engineering decisions. Electrical Power Cable Engineering, Second Edition meets its complex subject in a readable fashion, especially for those with limited background and experience…sufficient detail is provided for those with greater need in evaluating different cables for specific applications. Electrical Power Cable Engineering, Second Edition remains the foremost reference on universally use...

Electrical Engineering Dictionary CRCnetBASE 2000 provides workable definitions for practicing engineers, serves as a reference and research tool for students, and offers practical information for scientists and engineers in other disciplines. Areas examined include applied electrical engineering, microwave engineering, control engineering, power engineering,digital systems engineering, and device electronics. CRCnetBASE provides handbooks as living, evolving documents - expanding as knowledge expands, growing as technology advances, and reaching to meet your information needs instantly. If you don't seed you're going to confuse an anode and cathode when it really matters most. Download link http://www.keepandshare.com/doc/2291528/electrical-engineering-dictionary-7-0-meg?da=y

Upon completion of Basics of Electricity you will be able to: •  Explain the difference between conductors and insulators •  Use Ohm’s law to calculate current, voltage, and resistance •  Calculate equivalent resistance for series, parallel, or series-parallel circuits •  Calculate voltage drop across a resistor •  Calculate power given other basic values •  Identify factors that determine the strength and polarity of a current-carrying coil’s magnetic field •  Determine peak, instantaneous, and effective values of an AC sine wave •  Identify factors that effect inductive reactance and capacitive reactance in an AC circuit •  Calculate total impedance of an AC circuit •  Explain the difference between real power and apparent power in an AC circuit •  Calculate primary and secondary voltages of single-phase and three-phase transformers •  Calculate the required apparent power for a transformer This knowledge will ...

Electrical Power Equipment Maintenance and Testing 2nd Edition is a definitive text that covers all aspects of testing and maintenance of the equipment found in electrical power systems serving industrial, commercial, utility substations, and generating plants. It addresses practical aspects of routing testing and maintenance and presents both the methodologies and engineering basics needed to carry out these tasks. It is an essential reference for engineers and technicians responsible for the operation, maintenance, and testing of power system equipment. Comprehensive coverage includes dielectric theory, dissolved gas analysis, cable fault locating, ground resistance measurements, and power factor, dissipation factor, DC, breaker, and relay testing methods. This practical guide provides comprehensive and up-to-date information on the testing and maintenance of electrical power systems equipment and apparatus found in utility, industrial, commercial, and institutional facili...

The book covers all aspects of distribution engineering from basic system planning and concepts through distribution system protection and reliability. The author brings to the table years of experience and, using this as a foundation, demonstrates how to design, analyze, and perform modern distribution system engineering. He takes special care to cover industry terms and symbols, providing a glossary and clearly defining each term when it is introduced. The discussion of distribution planning and design considerations goes beyond the usual analytical and qualitative analysis and emphasizes the economical explication and overall impact of the distribution design considerations discussed. See what’s new in the Second Edition: ·         Topics such as automation of distribution systems, advanced SCADA systems, computer applications, substation grounding, lightning protection, and insulators ·         Chapter on electric power quality · ...

This book is a practical treatment of power system design within the oil, gas, petrochemical and offshore industries. These have significantly different characteristics to large-scale power generation and long distance public utility industries. Developed from a series of lectures on electrical power systems given to oil company staff and university students, Sheldrake's work provides a careful balance between sufficient mathematical theory and comprehensive practical application knowledge. Features of the text include: -Comprehensive handbook detailing the application of electrical engineering to the oil, gas and petrochemical industries -Practical guidance to the electrical systems equipment used on off-shore production platforms, drilling rigs, pipelines, refineries and chemical plants -Summaries of the necessary theories behind the design together with practical guidance on selecting the correct electrical equipment and systems required -Presents numerous 'rule of ...

The ANSI Standard Device Numbers denote what features a protective device supports (such as a relay or circuit breaker). These types of devices protect electrical systems and components from damage when an unwanted event occurs, such as an electrical fault. ANSI Standard Device Numbers are defined by ANSI (American National Standard Institute). 1 - Master Element 2 - Time Delay Starting or Closing Relay 3 - Checking or Interlocking Relay 4 - Master Contactor 5 - Stopping Device 6 - Starting Circuit Breaker 7 - Anode Circuit Breaker 8 - Control Power Disconnecting Device 9 - Reversing Device 10 - Unit Sequence Switch 11 - Reserved for future application 12 - Overspeed Device 13 - Synchronous-speed Device 14 - Underspeed Device 15 - Speed - or Frequency-Matching Device 16 - Reserved for future application 17 - Shunting or Discharge Switch 18 - Accelerating or Decelerating Device 19 - Starting to Running Transition Contactor 20 - Elect. operated valve (solenoid val...

Overcurrent Circuit protection would be unnecessary if overloads and short circuits could be eliminated. Unfortunately, overloads and short circuits do occur. To protect a circuit against these currents, a protective device must determine when a fault condition develops and automatically disconnect the electrical equipment from the voltage source. An overcurrent protection device must be able to recognize the difference between overcurrents and short circuits and respond in the proper way. Slight overcurrents can be allowed to continue for some period of time, but as the current magnitude increases, the protection device must open faster. Short circuits must be interrupted instantly. Several devices are available to accomplish this. Fuse A fuse is a one-shot device. The heat produced by overcurrent causes the current carrying element to melt open, disconnecting the load from the source voltage. Non time-Delay Fuse Non time-delay fuses provide excellent ...

In order to analyze the electric characteristics of the UHV double circuit transmission line system , a simulation model is built on the Real Time Digital Simulator (RTDS) based on the design parameters of the very first UHV double circuit transmission line system in China .To study and master the electric characteristics of the UHV double circuit transmission line system thoroughly special compare between the UHV double circuit transmission line system and the UHV single line system and the compare between the UHV and EHV double circuit transmission line system model are made . It can be concluded the double circuit transmission line system has the following features: The ingredient of the  harmonics in the fault current and voltage are redundant .There are large DC components included in the fault current and the decaying process are very slow. The amplitude of the recovery voltage are quite high ,and the bea...

Most engineers have some familiarity with two commonly known delta connections that give either a +30 0  or - 30 0  phase shift of positive sequence voltages and currents, and just these two configurations seem to cause extensive confusion. There are actually many other ways to configure a wye or delta that give other phase shifts, and to further complicate matters, there is the occasional zigzag winding application and the additional confusion over what occurs when CTs are connected in delta. These alternate transformer winding configurations are sometimes referred to by terms such as Dy# or Yy#, or Yd#, Dz#, and Yz#, and where the # can be, seemingly, almost any hour of the clock, hence the term “around the clock” phase shifting is sometimes heard. The paper will review the variety of possible winding configuration and give examples of the nomenclature that is used with them and how these various phase shifts are  created. The p...

 Vibration Dampers are used to absorb Aolian Vibrations of conductor of Transmission Lines, as well as ground wire, OPGW, and ADSS. It is mostly composed of the following; Weights – made up of cast iron, Clamp – made up of Aluminum Alloy, Nuts and Bolts made up of galvanized or stainless steel and Messenger cable made up of Galvanized Steel.   Vibration Dampers are used in areas of severe vibration. Dampers act to decrease aolian vibration amplitudes thereby reduce the dynamic bending stress at hardware location and extend conductor life. These fatigues stresses have maxima at suspension and dead end attachments. They can also occur at mass discontinuities and may lead to failures of individual strands. In composite conductors (ACSR, ACCR, etc. ) it may eventually lead to failure of all aluminum layers. How Vibration Damper Works When a vibration wave passes the damper location, the clamp of a suspension type damper oscillates up and down, causing flexure of the damper cab...

 Aolian Vibrations, also called Karman Vibration is the result of wind forces acting transversely on the conductor which causes alternating excitations in the vertical direction. Aeolian vibrations occur almost on any transmission line, for low to moderate steady winds. They are characterised by small amplitudes of vibration (one conductor diameter) with frequency between 5 and 100 Hz, depending on the conductor size and tensile load. This steady wind will create air vortices or eddies on the lee side of the conductor. These vortices on the other hand will detach at regular intervals from the top and bottom area if the conductor, creating a force in the conductor that is alternately impressed from above and below. Aeolian vibrations cause an alternate bending strain of the conductor at the suspension clamp (where bending stiffness is no more negligible) and, depending on the strain level, may cause fatigue failures of the cable strands. These effects on the conducto...

XLPE is acronym for Cross-Linked Polyethelene. It is used as one of the major parts of power cable, particularly in its insulation. The other parts are the conductor and jacket. It is made up of Polyethylene or polythene with bonds that link one polymer chain to another. XLPE was first patented in 1959 by Dr. Frank Percopio.It was not widely used then due to the high cost of its production until the 1980's. Its superior allowable emergency temperatures made them the choice for power feeder cables in commercial and industrial applications. XLPE did not melt and flow as did the HMWPE material. Advantages of XLPE Cables over Other Insulation Types             Low Permittivity             Low Dielectric Losses             High Initial Dielectric Strength          ...

Surge Arresters are used to limit voltage surges on an electrical system to level that it can be controlled. It is designed and connected between a conductor of an electrical system and ground to limit the magnitude of transient over voltages on equipment. Surge Arresters Surge Arresters are the most commonly used add-on equipment for over voltage protection. It very helpful in limiting over voltage on equipment by discharging or bypassing surge current, prevent continued flow of follow current to ground, and is capable of repeating these functions as specified. WHAT EXACTLY DOES A SURGE ARRESTER DO? 1.       Surge Arresters does not absorb the lightning. 2.       Surge Arresters does not stop the lightning. 3.       Surge Arresters divert the lightning to ground. 4.       Surge Arresters clamp (limit) the voltage produced by lightning. 5.     ...

As the voice of the U.S. standards and conformity assessment system, the American National Standards Institute (ANSI) empowers its members and constituents to strengthen the U.S. marketplace position in the global economy while helping to assure the safety and health of consumers and the protection of the environment. The Institute oversees the creation, promulgation and use of thousands of norms and guidelines that directly impact businesses in nearly every sector: from acoustical devices to construction equipment, from dairy and livestock production to energy distribution, and many more. ANSI is also actively engaged in accrediting programs that assess conformance to standards – including globally-recognized cross-sector programs such as the ISO 9000 (quality) and ISO 14000 (environmental) management systems. Mission To enhance both the global competitiveness of U.S. business and the U.S. quality of life by promoting and facilitating voluntary consensus standards and conformity a...

 Armor Rods are intended to protect against bending, compression, abrasion, and arc-over, and to provide repair. The degree of protection needed on a specific line depends upon a number of factors such as line design, temperature, tension, exposure to wind flow, and vibration history on similar construction in the same area. Armor rods are recommended as minimum protection for clamp type supports or suspensions. Line Guards on the other hand are recommended as minimum protection for hand tied spans. Armor rods may be used to restore full conductance and strength to ACSR and aluminum conductors where damage does not exceed approximately 50% of the outer strand layer. Tapping over applied aluminum Armor Rods is permissible. Where it is known that tapping clamps will be installed over Armor rods, it is recommended that the conductor be thoroughly wire brushed clean, then an inhibitor be applied.