power systems loss

Typical Loss for Amorphous-Metal Core Distribution Transformers. The losses shown in the table are the typical values of a amorphous-metal cored distribution transformers. Core loss and Winding loss (watts) varies relatively as with the increase of the distribution transformer's kVA capacity. Also shown are he respective kilo-watthour loss in annual basis for different transformer capacity in 30% and 40% load factor. Annual kwh are based on peak transformer kW loading equal to kVA size.

Typical Loss for Silicon-Core Distribution Transformers The losses shown in the table are the typical values of silicon-cored distribution transformers. Core loss and Winding loss (watts) varies relatively as with the increase of the distribution transformer's kVA capacity. Also shown are he respective kilo-watthour loss in annual basis for different transformer capacity in 30% and 40% load factor. Annual kwh are based on peak transformer kW loading equal to kVA size.

PARALLELING TRANSFORMER’S LOADING CONSIDERATIONS Paralleling transformers has been practiced mostly in commercial and industrial facilities along with electric utilities where reliability and the quality of power is the main objective. For many years, it has been a practice that transformers installed for paralleling have the same kVA, turns ratio and impedances which served also as a reason why most of the engineers today is having a hard time understanding load sharing and circulating currents. Often times during transformer replacement or upgrades, they tend to not know the impact of paralleling transformers with different parameters and could later result to transformer failures. Simple transformer paralleling with the same kVA, turns ratio and impedance is not enough in practicing this kind of activity. An engineer must consider all possible scenarios and simulate the effects of his decisions. The most appropriate type of transformers that should be use in paralleling must have t

SPOTLIGHT ON MODERN TRANSFORMER DESIGN BOOK DOWNLOAD Increasing competition in the global transformer market has put tremendous responsibilities on the industry to increase reliability while reducing cost. Spotlight on Modern Transformer Design introduces a novel approach to transformer design using artificial intelligence (AI) techniques in combination with finite element method (FEM). Today, AI is widely used for modeling nonlinear and large-scale systems, especially when explicit mathematical models are difficult to obtain or completely lacking. Moreover, AI is computationally efficient in solving hard optimization problems. On the other hand, FEM is particularly capable of dealing with complex geometries, and also yields stable and accurate solutions. Many numerical examples throughout the book illustrate the application of the techniques discussed to a variety of real-life transformer design problems, including: • problems relating to the prediction of no-load losses; • winding

TRANSFORMER HANDBOOK: ABB This Transformer Handbook prepared by ABB contains a wide range of power and distribution transformers that aims to serve as a guide in understanding, selection, ordering, operation and maintenance of this transformers. The construction of this devices follows standards to the likings of the customers including but not limited to IEC, CENELEC, and ANSI/IEEE. This Handbook although focuses on ABB products, does not significantly differs to the common practice in specifying transformers and ABB based this handbook on their knowledge and experience. Listed below are the main topics that were discussed in this handbook: Every point found in the list are carefully considered. Also, a portion of this handbook tackles all the available standards that are relevant to transformer information. Transformer Types and their Application Quality, Internal Control, Sustainability Loss Capitalization and Optimum Transformer Design Information Required with Enquiry and Ord

TRANSFORMER CATALOGUE: A SAMPLE FROM MANUFACTURER Transformers are one of the primary components for the transmission and distribution of electrical energy. Their design results mainly from the range of application, the construction, the rated power and the voltage level. The scope of transformer types starts with generator transformers and ends with distribution transformers. Transformers which are directly connected to the generator of the power station are called generator transformers. Their power range goes up to far above 1000 MVA. Their voltage range extends to approx.1500 kV. The connection between the different highvoltage system levels is made via network transformers (network interconnecting transformers). Their power range exceeds 1000 MVA. The voltage range exceeds 1500 kV. Distribution transformers are within the range from 50 to 2500 kVA and max. 36 kV. In the last step, they distribute the electrical energy to the consumers by feeding from the high-voltage into the low-

J & P TRANSFORMER BOOK DOWNLOAD By:Martin J. Heathcote Maintaining appropriate power systems and equipment expertise is necessary for a utility to support the reliability, availability, and quality of service goals demanded by energy consumers now and into the future. However, transformer talent is at a premium today, and all aspects of the power industry are suffering a diminishing of the supply of knowledgeable and experienced engineers. Now in print for over 80 years since initial publication in 1925 by Johnson & Phillips Ltd, the J & P Transformer Book continues to withstand the test of time as a key body of reference material for students, teachers, and all whose careers are involved in the engineering processes associated with power delivery, and particularly with transformer design, manufacture, testing, procurement, application, operation, maintenance, condition assessment and life extension. Current experience and knowledge have been brought into this thirteenth

TRANSFORMERS BOOK By: Bharat Heavy Electricals Limited CHECK OUT THIS BOOK!

IEEE STANDARD FOR TRANSFORMERS TABLE OF CONTENTS Listed below are some of the IEEE subscription for Power, Distribution and Regulating Transformers. Unapproved drafts are proposed IEEE standards. As such, these documents are subject to change. So, take a precautionary actions in using this standards. Because these drafts are unapproved, they must not be utilized for any conformance/compliance purposes. 1-2000 (R2005) IEEE Recommended Prasctice--General Principles for Temperature Limits in the Rating of Electric Equipment and for the Evaluation of Electrical Insulation 62-1995 (R2005) IEEE Guide for Diagnostic Field Testing of Electric Power Apparatus--Part 1: Oil Filled Power Transformers, Regulators, and Reactors 259-1999 (R2004)    IEEE Standard Test Procedure for Evaluation of Systems of Insulation for Dry-Type Specialty and General Purpose Transformers 315-1975 (R1993) IEEE Graphic Symbols for Electrical and Electronics Diagrams (Including Reference Designation Letters) Bound

LOAD LOSS IN POWER TRANSFORMER LOAD LOSS also known as winding loss is similar to the analysis of a transmission line represented by the I squared R formula. Load loss is called this way because the losses here vary with the square of the load current. Higher load means higher loss and lower load means lower loss. In the past, load loss is referred to as copper loss but later this has been corrected since modern transformers now use aluminium windings in substitute for copper. Losses occurring in transformers are mostly load losses, so the maximization of the transformer use with respect to losses is a very vital form of analysis.  

load losses: Those losses that are incident to the carrying of a specified load. Load losses include I 2 R loss in the current carrying parts (windings, leads, busbars, bushings), eddy losses in conductors due to eddy currents and circulating currents (if any) in parallel windings or in parallel winding strands, and stray lossinduced by leakage flux in the tank, core clamps, or other structural parts. In equation form:  PLL = I 2 R+PEC+PSL where PLL is the load loss (W) I 2 R is the loss due to current and resistance (W) PEC is the eddy current loss (W) PSL is the stray loss (W). See also: no-load (excitation) losses.

POWER AND DISTRIBUTION TRANSFORMER TERMS DEFINITION 1 accessories: Devices that perform a secondary or minor duty as an adjunct or refinement to the primary or major duty of a unit of equipment. alternating current: A periodic current the average value of which over a period is zero. ambient temperature: The temperature of the medium such as air, water, or earth into which the heat of the equipment is dissipated. ampacity: Current-carrying capacity expressed in amperes, of a wire or cable under stated thermal conditions. autotransformer: A transformer in which at least two windings have a common section.

BASIC TRANSFORMER PRINCIPLES Transformer has been one of the most significant inventions of human kind in relation to electricity. Its construction became a breakthrough to all other discoveries that has elevated man kind's way of living. At present, it is almost unimaginable to think if transformers have not even been around. Two key principles has been the main reason for its existence; that a magnetic field can be produced from electric current termed as electromagnetism and the other one is that voltage can be induced at the ends of a coil whenver a changing magnetic field within a coil of wire also termed as electromagnetic induction. Today, various forms of transformers exist at our disposal, from the smallest size to the gigantic forms also known as power transformers all for the purpose of serving man's needs. Before we discuss the losses that exist in the transformers found in our power system, let us first have the time to review its basic principles of operation. W

HISTORY-EARLY TRANSFORMERS 1895-1920  A tour of the three generations of transformers that helped make possible early power transmission. These step up transformers sent power 22 miles to Sacramento with a 10% loss. The first transformers at Folsom(1895) were air cooled and made by William Stanley - pioneer of the transformer. The second generation was made by Westinghouse, and the third by Alice Calmers (1920).

Beside Transmission Lines , the distribution of electrical power from one place to another would be impossible without the use of transformers. It would be very impractical if not impossible to transmit a usable voltage level say 240V over a long distance transmission. With the help of transformers, power transmission in the modern era has been very successful. Various forms of transformers exist today each with its own purpose and function. The development of this human invention, the transformer, has come a long way from the day of its inception. One may see the evolution that occurred which makes it a very fascinating device that has help human kind since time immemorial.

  Typical Outdoor type Power Transformer  For students who are not familiar with the physical appearance of a Power Transformer, this is how it looks like. I want to share this since back when I was in college I was not familiar with it too.  Power Transformer without attached conductors There are many aspects to consider with in specifying a Power Transformer that should be used in a system. The preferences of the project engineer is always in challenge. For more information regarding transformer specification, you can visit this  LINK

How to compute for the losses found in transformers? We mention in the previous articles the different types of internel energy dissipation of transformers . Here we will be showing you some basic formulas used in computing for the said losses ;

KNOWN TRANSFORMER LOSSES(This is worth reading) ( Taken from Wikipedia) An ideal transformer would have no energy losses, and would be 100% efficient. In practical transformers energy is dissipated in the windings, core, and surrounding structures. Larger transformers are generally more efficient, and those rated for electricity distribution usually perform better than 98%. Experimental transformers using superconducting windings achieve efficiencies of 99.85%. The increase in efficiency can save considerable energy, and hence money, in a large heavily-loaded transformer; the trade-off is in the additional initial and running cost of the superconducting design. Losses in transformers (excluding associated circuitry) vary with load current, and may be expressed as "no-load" or "full-load" loss. Winding resistance dominates load losses, whereas hysteresis and eddy currents losses contribute to over 99% of the no-load loss. The no-load loss can be signifi

 Schematic of an Ideal Transformer Beside the conductors in the network, the second most contributors to the power loss in the Power System are the transformers. Two known types of losses that go with this device are the copper or also known as the winding loss and the core loss. While the core loss can still broken down into two components namely, the eddy current loss and the hysteresis loss. We all know from our academics that an ideal transformer must have an incoming power equals the outgoing. In reality however, the electrical nature of the transformers components still prevails. Since its winding and the core is all made up of earthly materials, they are also subjected to resistance and reactance. A small amount of power is still dissipated in these materials during operation and this is what we generally consider as the transformer loss. Like any other device, transformers are also categorized to many types. Different types of connection and construction makes t

Ask a kid what he thinks about a tranformer and he will tell you "Optimus Prime". Most of us don’t know well the importance of transformer in any electrical system. Contrary to popular belief of which one considers a transformer as just another type of electrical device, transformers especially power transformers plays a significant role in keeping the power system in order. Distant transmission of power would be very impossible in the absence of a transformer and utilizing enough amount of voltage in our homes would also be just unimaginable.  A transformer does not only transform one voltage level to another but it also ensures that the energy is transferred from one circuit to another during the process effectively.  The discovery and understanding of a transformer and the principles behind is broad enough for us to no longer discuss it. It is the duty of a college professor to enlighten you with the basics of transformer operation. What I am trying to show you here a