The vector group provides a simple way of indicating how the internal connections of a transformer are arranged. 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. Jun 29, 2018 understanding transformer vector group transformer is magnetically coupled circuit its primary and secondary voltages either in phase or out of phase to say them in phase or out of phase will all depend upon polarity considerations before to discussing polarity we will see something about notational basics of electricity 3. Rphase hv and rphase lv shorted for all vector group of transformer. The vector group designation indicates the windings configurations and the difference in phase angle between them. This cannot be avoided by selecting a tansformer with a particular vector group. Separate singlephase transformers can be used and externally interconnected to yield the same results as a 3phase unit. The vector group provides a simple way of indicating how the connections of a transformer are arranged. Vector group test of transformer the vector group of transformer is an essential property for successful parallel operation of transformers. You can also choose from single, three vector group transformer there are 97 suppliers who sells vector group transformer on, mainly located in asia. What is an interleaved connection of a transformer winding. Electrical technology and industrial practice 7,342 views 15. A vector group is the international electrotechnical commission iec method of categorizing the high voltage hv windings and low voltage lv. Vector group test of transformerthe vector group of transformer is an essential property for successful parallel operation of transformers.
Transformer, voltage ratio, vector group, impedance, shortwhat is vector group. What is the significance of vector grouping in power. How to determine transformer vector group dv power. But the transformer in which a part of windings is common to. A transformer vector group is required to be known from the angle of parallel operation of two similar transformers. These phasor groups can be better understand by the following examples. This was done in order to create a notation for threephase transformer winding configuration. Friends, i have a question about vector group ynd11. The three phase transformer windings can be connected.
Dec 30, 2017 transformer vector group determinationelectrical engineeringelectrical technology duration. Significance of vector group of transformer your electrical. Vector groups for transformers in according to en61558 vde0570. May 9, 2012 9 comments 7 auto transformer connection. Vector group test of power transformer electrical mastar. Performing transformer vector group test prepared by ir kamarul ariffin yahya uptp27 lead electrical engineer p27 amt supervisor. In electrical engineering, a vector group is the international electrotechnical commission iec. Explanation and vectorgroups to applicate 1 phase and 3 phase autotransformers autotransformers do not provide galvanic isolation. Description of vector group testing of vector group bangla tutorial for power point slide go to eee practical knowledge. An ordinary transformer consists of two windings called primary winding and secondary winding. The vector diagrams are given in the name plate details of the transformer. Vector group test of power transformer electrical4u. Every transformer contains its own vector group as shown below figure. Vector group of transformer technology for volt and current.
In a transformer, when we increase the load on the secondary side, how does the impedance of the primary winding decrease to increase the curr. All transformers are subjected to various tests at the manufacturer. Department of electrical and electronics engineering. 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. It also determines the high voltage and low voltage windings arrangement of three phase transformers. The first letter d refers to the primary configuration being a delta connection the y refers to the secondary configuration being a star connection. The secondary side of a distribution transformer must be yn or zn to provide the neutral connection, and usually the primary side connection is delta to avoid 3rd harmonics to inject to the.
The vector group designation indicates the windings configurations. The vector group transformer test is important for connecting two power transformer in parallel. I was lucky because the transformer ratio testset 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. The transformer vector group show the phase difference between the primary and secondary sides of the transformer. 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. Understanding transformer vector group transformer is magnetically coupled circuit its primary and secondary voltages either in phase or out of phase to say them in phase or out of phase will all depend upon polarity considerations before to discussing polarity we will see something about notational basics of electricity 3. Understanding vector group of transformer part 1 the primary windings are connected in one of several ways. The harmonics in a transformer are present only in the transformer inrush current predominantly 2 nd harmonic content. If the two transformers of different vector groups are connected in parallel then phase difference exist between the secondary of the transformers and large circulating current flows between the two transformers which is very damaging. Vector groups identify the winding connections and polarities of the primary and secondary. How to draw vector group of transformer from winding. Basically this vector group arrangement will define the physical displacement of the generator shaft and the electrical phase of.
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 transformervector groupis indicated on the name plate of transformer by the manufacturer. Transformer check of vector group the purpose of this series of tests is to check the polarity and the phase relationship of the multiple windings in a transformer. The transformer vector group is indicated on the name plate of transformer by the manufacturer. Dy connection y winding nullifies 3rd harmonics, preventing it to be reflected on delta side.
Explanation and vector groups to applicate 1 phase and 3 phase autotransformers autotransformers do not provide galvanic isolation. Three phase transformer consists of three sets of primary windings, one for each phase, and three sets of secondary windings wound on the same iron core. The phase sequence or the order in which the phases reach their maximum. The phase sequence or the order in which the phases reach their. The test is carried out simultaneously with the transformer turns ratio test when using a turns ratio test set. Jun 18, 2012 the transformer vector group is indicated on the name plate of transformer by the manufacturer. The vector group of transformer is an essential property for successful parallel operation of transformers. Explanation and vectorgroups schmidbauer transformers. Vector group of transformer auto transformer connection. The following will tell you the suggestions with reasons. In other words the vector group of a transformer cannot aid in eliminating the harmonic content in its inrush current. 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. These two windings are magnetically coupled and electrically isolated.
Here yy 0 will mean its both the windings are starconnected and phase displacement between primary and secondary emfs is zero. The naming convention popularly known as vector group of transformer was established by the international electrotechnical commission iec through iec 600761. What is meant by vector group for transformers and why is it. The vector group determines the phase displacement between the primary and the secondary winding. The real time examples for phasor groups of transformer are given here.
Why vector group of distribution transformer is dyn11. Here yy 0 will mean its both the windings are starconnected and phase displacement between primary and secondary emfs is zero degree. What is meant by vector group for transformers and why is. The three phase transformer is connected in various ways. Significance of vector group of transformer on the nameplate of threephase transformer vector group is printed as yy 0, dd 1 etc. Transformers connected in parallel must have the same vector group. Three phase transformer vector grouping significance. Vector group is punched on the name plate based on the user requirement by the manufacture. The letters indicate the winding configuration as follows. The determination of vector group of transformers is very important before. By far the most common vector configuration of three phase transformers we manufacture is the dyn11 vector group. 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.
The vector group indicates the phase difference between the primary and secondary sides, introduced due to that particular configuration. One system for multiple tests on power transformers. The clock method is used to produce the numerical index of. Vector group of 3 winding transformer cr4 discussion thread. Understanding transformer vector group linkedin slideshare. A wide variety of vector group transformer options are available to you, such as power, electronic, and high frequency. According to iec764, the value of vector group can be 0,1,2,4,5,6,7,8,10,11.
Transformer is the most important unit in an electrical distribution network. The determination of vector group of transformers is very important before connecting two or more transformers in parallel. Mainly, the type of transformer connections are divided in 4 below groups. There is no technical difference between the one vector groups i. From a vector group one can determine the phaseshift between primary and secondary. This symbol indicates the winding connections and their relative phase displacement by means of a numerical index e. The vector group indicates the phase difference between the primary and secondary sides, introduced due to that particular configuration of transformer windings connection. Based on the windings connection, the vector group of the transformer is determined. Understanding transformer vector groups valence electrical.
Sep 26, 2017 the vector group transformer test is important for connecting two power transformer in parallel. Based on the windings connection, the vector group of the transformer. The vector group of transformer is the phase difference between the primary and the secondary sides. Contents hide 1 basic idea about transformer vector group 1. Transformer vector group determinationelectrical engineeringelectrical technology duration. A user friendly simulation for transformer vector group. 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.
The vector group of a transformer defines the connection of the hv and lv windings. 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 shared limbs. Pdf performing transformer vector group test kamarul. What is meant by vector group for transformers and why is it important.
Heat run test iec 600762 excitation current measurement. The clock method is used to produce the numerical index of the vector group. Vector group test of power transformer electrical study. Understanding transformer vector groups transformer vector groups can be a difficult concept to understand. Vector group of 3phase transformer electrical concepts. The connection of all the windings in a threephase transformer is indicated by a vector group symbol. They have electroconductive connection between input and output winding. Dec 22, 2017 description of vector group testing of vector group bangla tutorial for power point slide go to eee practical knowledge. 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. Dec 12, 20 the transformer vector group is indicated on the name plate of transformer by the manufacturer. Aim of vector group test is at site is to check if their is any damage in the windings during transportation and erection. The three phase transformer windings can be connected several ways. The primary windings are connected in one of several.