Vector group is punched on the name plate based on the user requirement by the manufacture. The clock method is used to produce the numerical index of the vector group. The vector group indicates the phase difference between the primary and secondary sides, introduced due to that particular configuration of transformer windings connection. When setting the vector group, a number between 1 and 24 two winding transformer. Hi, all the transformers in a subtransmission network are dyn11, in another part of the network a transformer with the vector group of ynd1 is going to be used for an industrial complex. Importance and elimination of third harmonics application and selection of vector group of transformer. Dy connection y winding nullifies 3rd harmonics, preventing it to be reflected on delta side. Through vector group of a transformer we can know that the winding configuration of a transformer. Vector group test of transformerthe vector group of transformer is an essential property for successful parallel operation of transformers. Transformer vecttransformer vector group test conditionsor group.
Dec 12, 2017 vector group test, check the voltage phase shift of two or more transformer. Transformer vector group depends upon removing harmonics. 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. Vector group test, check the voltage phase shift of two or more transformer. Department of electrical and electronics engineering. Vector group of 3 winding transformer cr4 discussion thread. 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. Significance of vector group of transformer your electrical. The transformer vector group is indicated on the name plate of transformer by the manufacturer. If your instruments have inaccurate measurements maybe it is time to contact us to calibrate them. Transformer, voltage ratio, vector group, impedance, short circuit impedance, load losses.
In other words the vector group of a transformer cannot aid in eliminating the harmonic content in its inrush current. 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. The vector group provides a simple way of indicating how the internal connections of a transformer are arranged. Note that when determining the angle between h1 and x1, the rotation must be clockwise. Transformer, voltage ratio, vector group, impedance, shortwhat is vector group.
These two windings are magnetically coupled and electrically isolated. The vector group test is importent test in the transformer testing. An ordinary transformer consists of two windings called primary winding and secondary winding. From a vector group one can determine the phaseshift between primary and secondary. Vector group test of transformer is done for detecting the vector group. Dv power qualified engineers will gladly assist you during measurements or answer your technical questions from different areas of the electrical power market. Measure the voltages in various combination on both side of the transformer hv lv. Vector group of 3phase transformer electrical concepts.
It should be noted that it is not possible to generate a zero phase shift between primary and secondary with a combination of delta and star windings. Here yy 0 will mean its both the windings are starconnected and phase displacement between primary and secondary emfs is zero degree. 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. In this format half of each secondary is wound on a different leg of the transformer. But after the winding connection is made it is necessary to check if the desired vector group has been achieved. Measure the voltage between the primary and the secondary terminals. If two transformers of different vector groups are connected in parallel then. First, connect the test power supply to high voltage winding. Test results on two coaxially wound transformers with different tube geometries, designed for 50 kw, 50 khz, primary voltage of 200 v, and secondary voltage of v two windings, are presented. Without earthing the winding neutral points, interconnect one phase of hv winding say 1u to the corresponding phase of lv winding 2u and apply a balanced 3 phase low voltage to the hv winding.
The vector group of transformer is an essential property for successful parallel operation of transformers. In this way you can measure the vector group of any 3 phase transformer. Applicationnote how to determine transformer vector group. Transformer vector group free download as powerpoint presentation. A vector group is a method of specifying a threephase transformer or transformer bank method of connection and its angular displacement. This symbol indicates the winding connections and their relative phase displacement by means of a numerical index e. One procedure of vector group testing of transformer is explained as below. This webinar brought to you by the relion product family. Why are ynd1ynd11 the most common vector groups for power. Pdf transformer vector group test conditions k pandian. The determination of vector group of transformers is very important before connecting two or more transformers in parallel. Rphase hv and rphase lv shorted for all vector group of transformer. Dec 22, 2017 description of vector group testing of vector group bangla tutorial for power point slide go to eee practical knowledge. The transformer vector group show the phase difference between the primary and secondary sides of the transformer.
Vector group test of transformer testing of transformer. The letters indicate the winding configuration as follows. Why isnt the primary winding deltaconnected that way. Jun 18, 2012 from a vector group one can determine the phaseshift between primary and secondary. Vector group test of power transformer electrical study app. Vector group can be used as basis in setting the phase compensator factor for numerical transformer differential relays, i. The power transformer connection type, the vector group and the subtraction of zero sequence currents onoff are setting parameters from these the differential protection calculates offline the matrix coefficients, which are then used in the online calculations. The vector group provides a simple way of indicating how the connections of a transformer are arranged. There is no technical difference between the one vector groups i. From your question above, i presume that ur understanding of the transformer is not complete. 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.
Vector group of transformers transformer electric power. A 3ph transformer is wired internally in different ways to. Transformer vector groups can be a difficult concept to understand. Understanding vector group of transformer part 1 the primary windings are connected in one of several ways. Transformers built to ansi standards usually do not have the vector group shown on their nameplate and instead a vector diagram is given to show the relationship between the primary and other windings. I was lucky because the transformer ratio test set i used for the first couple of years in my career allowed me to make threephase connections, but it was really a singlephase tester and i had to change the connections one phase at time. But the transformer in which a part of windings is common to both primary and secondary is called auto transformer. Transformer vector group connections are made based on the winding polarity. The three phase transformer is connected in various ways. Vector group test of power transformer electrical study. What is the meaning of transformer vector group yna0d1.
The following requirements shall be fulfilled depending on the vector group of the transformers. It also determines the high voltage and low voltage windings arrangement of three phase transformers. Some basic connections of a 3phase transformer along with the idea of vector grouping is introduced. Transformer connections from the same group can be. These tests are done when the tap of transformer is nominal. Nov 05, 20 connections for dy11 and dy1 transformers and the corresponding vector groupings are given in figure. The vector group indicates the phase difference between the primary and secondary sides, introduced due to that particular configuration. 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. Vector group test of power transformer electrical mastar. Description of vector group testing of vector group bangla tutorial for power point slide go to eee practical knowledge. Nov 05, 20 vector group test is done in order to know the phase displacement between the high voltage and low voltage winding. What is the meaning of transformer vector group yna0d1 answers. The connection of all the windings in a threephase transformer is indicated by a vector group symbol.
The vector group transformer test is important for connecting two power transformer in parallel. Understanding transformer vector groups valence electrical. Vector groups are the iec method of categorizing the primary and secondary winding configurations of 3phase transformers. Please note that u cannot have two different vector group on a single transformer,i. Dv power smart test instruments for reliable electrical. What is the test procedure of vector group of a transformer. On the name plate of a three phase transformer, the vector group is written as. Vector group of transformers free download as powerpoint presentation. In the system adopted by the iec, the vector group is indicated by a code consisting of two or three letters, followed by one or two numeric digits. Performing transformer vector group test prepared by ir kamarul ariffin yahya uptp27 lead electrical engineer p27 amt supervisor. Vector group test of power transformer electrical4u.
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