These two windings are magnetically coupled and electrically isolated. Vector group test of transformer testing of transformer. Vector group of 3phase transformer electrical concepts. Significance of vector group of transformer on the nameplate of threephase transformer vector group is printed as yy 0, dd 1 etc. In other words the vector group of a transformer cannot aid in eliminating the harmonic content in its inrush current. This vector group test is done to confirm whether the vector group provided in the name plate is correct or not and also to confirm that the winding has not been damaged during transport. According to iec764, the value of vector group can be 0,1,2,4,5,6,7,8,10,11.
Understanding vector group of transformer part 1 the primary windings are connected in one of several ways. The phase sequence or the order in which the phases. Through vector group of a transformer we can know that the winding configuration of a transformer. A transformer threephase vector diagram is required for determining the fault calculation of an electrical power system. Practically, almost every electrical power system deals with three phase power. The method of comparing the vector couple voltages also allows measuring the angle phase slip between vectors at the same time 2. The standard test usually links the a and a terminals then applies a suitable safe test voltage to the hv winding, and the resulting voltages between terminals prove the vector group. Performing transformer vector group test prepared by ir kamarul ariffin yahya uptp27 lead electrical engineer p27 amt supervisor.
Transformer routine test measurement of voltage ratio. Transformer vector group determinationelectrical engineering. Autotransformer vector group cr4 discussion thread. The connection of all the windings in a threephase transformer is indicated by a vector group symbol. Practically, almost every electrical power system deals with three phase power threephase vector diagrams are commonly used to represent 3 phase transformers are known as transformer vector diagrams the voltages of a three phase. Vector group test of transformerthe vector group of transformer is. The determination of vector group of transformers is very important before connecting two or more transformers in parallel. In light of the windings association, the vector gathering of the transformer is resolved.
The phase sequence or the order in which the phases reach their maximum. Vector group of transformer electrical engineering portal. Hence every electrical power transformer must undergo through vector group test of transformer at factory site for ensuring the customer specified vector group of transformer. Transformer vector group connections are made based on the winding polarity. Why is a vector group test of transformer performed. From your question above, i presume that ur understanding of the transformer is not complete. Importance and elimination of third harmonics application and selection of vector group of transformer. Liggett group llc tobacco and new valley llc real estate, including douglas elliman. Dec 12, 20 if you are replacing a transformer, use the same vector group for the new transformer, otherwise the existing vts and cts used for protection and metering will not work properly. Note that when determining the angle between h1 and x1, the rotation must be clockwise. A vector group is a method of specifying a threephase transformer or transformer bank method of connection and its angular displacement. The three stage transformer windings can be joined a few ways. From a vector group one can determine the phaseshift between primary and secondary. The two most common configurations are the delta, in which the polarity end of one winding is connected to the nonpolarity end of the next, and the star, in which all three nonpolarities or polarity ends are connected together.
Transformer vector group the vector group test is importent test in the transformer testing. Transformer vector group test conditions transformer. Dec 22, 2017 description of vector group testing of vector group bangla tutorial for power point slide go to eee practical knowledge. Basic idea about transformer vector group in theory of a threephase transformer works like three equal and separated singlephase transformers working separately with three phase system with. Windings can be connected as delta, star, or interconnec. Oct 14, 2018 the real time examples for phasor groups of transformer are given here. Pdf transformer testing type test and routine test of. Every transformer contains its own vector group as shown below figure. Contents hide 1 basic idea about transformer vector group 1. The clock method is used to produce the numerical index of the vector group. This was done in order to create a notation for threephase transformer winding configuration. Here yy 0 will mean its both the windings are starconnected and phase displacement between primary and secondary emfs is zero degree. Vector group of 3 winding transformer cr4 discussion thread. Howard lorber has served as the companys president and chief executive officer since 1994.
May 23, 2012 the vector group indicates the phase difference between the primary and secondary sides, introduced due to that particular configuration of transformer windings connection. Introduction to vector group the vector group marks the circuitry of windings and their phase position to each other. Procedure of vector group test of transformer lets have a ynd11 transformer. How to draw transformer vector group connectionelectrical. Group 4 has phase displacement of 30 degree lead, i. A transformer of group 3 can be connected in parallel with that of group 4 by cross connecting any two of the three external connections on hv side, without any other changes. An unbalanced group of two or more forces is a group whose vector sum is not zero. Transformer testing type test and routine test of transformer electrical4u.
Pdf transformer vector group test conditions k pandian. These phasor groups can be better understand by the following examples. The real time examples for phasor groups of transformer are given here. Vector group test of power transformer electrical study app.
Liggett group llc founded in 1873, liggett group llc is the fourthlargest cigarette manufacturer in the u. Jun 18, 2012 from a vector group one can determine the phaseshift between primary and secondary. Transformer vector group determinationelectrical engineering electrical technology duration. Ms excel spreadsheet eep electrical engineering portal. Ratio and vector group test for trafo electric power. Codefree, selfmaintaining browser tests w datadog synthetics. Department of electrical and electronics engineering. Type tests are done mainly in a prototype unit not in all manufactured units in a lot. Only ynyn0, ynyn6, dyn1 and dyn11 transformers have been shown as example. Three phase transformer vector grouping significance. In electrical engineering, a vector group is the international electrotechnical commission iec method of categorizing the high voltage hv windings and low voltage lv winding configurations of threephase transformers. Threephase vector diagrams are commonly used to represent 3 phase transformers are known as transformer vector diagrams. This ms excel spreadsheet is actually detailed instruction for each procedure necessary for correct testing of power transformer.
Power transformer vector group testing by voltage method. An ordinary transformer consists of two windings called primary winding and secondary winding. If two transformers of different vector groups are connected in parallel then. It also determines the high voltage and low voltage windings arrangement of three phase transformers. Understand significance of vector groups interpret the vector group notations used on transformer name plates content. Aim of vector group test is at site is to check if their is any damage in the windings during transportation and erection. Training on vector groups of transformer presented by. Why vector group of distribution transformer is dyn11. Dec 12, 2017 vector group test, check the voltage phase shift of two or more transformer. Get access to premium hvmvlv technical articles, electrical engineering guides, research studies and much more. Whenever we connect two transformers in parallel, we need to make sure that the phase difference bw secondaries of both the transformer are identical.
This symbol indicates the winding connections and their relative phase displacement by means of a numerical index e. How do i draw vector group of transformer from winding connection. Vector group of transformers transformer electric power. Vector groups identify the winding connections and polarities of the primary and secondary. Transformer vector group free download as powerpoint presentation. Mar 23, 2019 a transformer threephase vector diagram is required for determining the fault calculation of an electrical power system. Vector group is an essential characteristics of 3 phase transformer. Hence every electrical power transformer must undergo through vector group test of. In electrical engineering, a vector group is the international electrotechnical commission iec. The clock method is used to produce the numerical index of the vector group, with each hour representing 30. Please note that u cannot have two different vector group on a single transformer,i. The vector group of transformer is an essential property for successful parallel operation of transformers.
Why are the u1 of hv and u2 of the lv side of a transformer in the dyn11 vector group test. Threephase transformer connections and vector groups for. Vector group test of power transformer electrical study. The three phase transformer is connected in various ways. Transformer tx is a very costly unit in an electrical distribution network. Hence every electrical power transformer must undergo through vector group test of transformer at factory site for ensuring the customer specified vector group of transformer the phase sequence or the order in which the phases. But after the winding connection is made it is necessary to check if the desired vector group has been achieved. How do you test yyn0 vector group of transformer answers.
Rphase hv and rphase lv shorted for all vector group of transformer. Oct 02, 2018 transformer vector group connections are made based on the winding polarity. The naming convention popularly known as vector group of transformer was established by the international electrotechnical commission iec through iec 600761. It means lv winding,which is star connected written in small letters means lv side and vice versais 30 degrees lagging by hv winding which is delta connected. Transformer vector group test procedure lfqx419apgo 2. How can you test the vector group of power transformers.
Depending on the type of the transformer, the input and output windings of a multiphase transformer are connected either as star y or delta d or zigzag z. Vector group test of power transformer electrical mastar. So it is utmost necessary to know how the inter connections to be made to. The vector diagrams are given in the name plate details of the transformer. Mainly, the type of transformer connections are divided in 4 below groups. What is the test procedure of vector group of a transformer. Sep 26, 2017 the vector group transformer test is important for connecting two power transformer in parallel. Description of vector group testing of vector group bangla tutorial for power point slide go to eee practical knowledge. In video we have shown the procedure to determine vector group of a transformer. Transformers connected in parallel must have the same vector group. P department of electrical and electronics engineering loyola institute of technology and science loyola nagar, thovalai, tamilnadu629302, india abstract transformer is the most important unit in an electrical distribution network.
It consists of a capital and small letter plus a code number. Transformer connections from the same group can be. Vector groups are the iec method of categorizing the primary and secondary winding configurations of 3phase transformers. Vector group is punched on the name plate based on the user requirement by the manufacture. How to draw vector group of transformer from winding. Going counterclockwise between h1 and x1 can give wrong phase angle, and therefore wrong phase displacement number, which leads to wrong vector group and possibly to wrong test results. Vector group test of power transformer electrical4u. Transformer vector group depends upon removing harmonics. Constructional features of three phase transformers three phase. Applicationnote how to determine transformer vector group. The transformer vector group show the phase difference between the primary and secondary sides of the transformer. Hence every electrical power transformer must undergo through vector group test of transformer at factory site for ensuring the customer specified vector group of transformer the phase sequence or the order in which the phases reach their maximum.
The capital letter a, b, c refers to the hv winding and the lower case a, b, c to the lv winding with a, b. Because generating transformer are ynd1 for neutralizing the load angle between 11 and 1. Significance of vector group of transformer your electrical. If we want to connect two transformer in parallel then their phase shift should be same, otherwise there will be a. The vector group transformer test is important for connecting two power transformer in parallel. But after the winding connection is made it is necessary to check if the desired vector group. Normally, dyn11 vector group using at distribution system. But the transformer in which a part of windings is common to both primary and secondary is called auto transformer. The vector group indicates the phase difference between the primary and secondary sides, introduced due to that particular configuration of transformer windings connection. Asked in electrical engineering how do you test yyn0 vector group of transformer. Dy connection y winding nullifies 3rd harmonics, preventing it to be reflected on delta side.
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