The primary and secondary windings of the transformer may be connected in either by wye y or delta. If a threephase set of voltages is applied to a y y transformer, the voltages in any phase will obe 120 apart from the voltages in any other phase. This knowledge is required for connecting the poly phase transformers in parallel. May, 2012 a user friendly simulation for transformer vector group abstract. The three phase transformer is connected in various ways. All transformers are subjected to various tests at the manufacturer. Understanding transformer vector groups transformer vector groups can be a difficult concept to understand. In addition to the voltage ratios and kva ratings, one of the most important specifications is the transformer vector group. Measure the voltages in various combination on both side of the transformer hv lv. In light of the windings association, the vector gathering of the transformer is resolved.
Performing transformer vector group test prepared by ir kamarul ariffin yahya uptp27 lead electrical engineer p27 amt supervisor. The transformer vector group is indicated on the name plate of. Understand significance of vector groups interpret the vector group notations used on transformer name plates content. The connection of all the windings in a threephase transformer is indicated by a vector group symbol. It also determines the high voltage and low voltage windings arrangement of three phase transformers. This relatively simple nomenclature provides important information about the way in which three phase windings are connected and any phase displacement that occurs. The vector group indicates the phase difference between the primary and secondary sides, introduced due to that particular configuration of transformer windings connection.
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 vector group designation indicates the windings configurations and the difference in phase angle between them. The transformer vector group is indicated on the name plate of transformer. Vector group test of power transformer electrical mastar. Vector groups identify the winding connections and polarities of the primary and secondary. 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. Contents hide 1 basic idea about transformer vector group 1. The vector diagrams are given in the name plate details of the transformer.
Understanding vector group of transformer part 1 the primary windings are connected in one of several ways. The transformer vector group is indicated on the name plate of transformer by the manufacturer. For q2, transformer vector group is very important especially when your system will eventually be connected another system in parallel at any point. But after the winding connection is made it is necessary to check if the desired vector group has been achieved. Vector groups the connection of all the windings in a threephase transformer is indicated by a vector group symbol. For each vector group need diffrent type of voltage combination to conform the vector group refer drawings. Applicationnote how to determine transformer vector group. Oct 14, 2018 the real time examples for phasor groups of transformer are given here. Draw out the diagrams and thoroughly understand it for yourself. Transformer, voltage ratio, vector group, impedance, shortwhat is vector group.
Transformer nameplates carry a vector group reference such at yy0, yd1, dyn11 etc. The connection of all the windings in a three phase transformer is indicated by a vector group symbol. The vector group of transformer is an essential property for successful parallel operation of transformers. 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. The naming convention popularly known as vector group of transformer was established by the international electrotechnical commission iec through iec 600761. But after the winding connection is made it is necessary to check if the desired vector group. Based on a previous discussion with a manufacturer, he said that the structure dyn11 is also simple in comparison with some other vector groups.
How to confirm the phase shifting transformer vector group relation, as below zny11. Significance of vector group of transformer on the nameplate of threephase transformer vector group is printed as yy 0, dd 1 etc. The three stage transformer windings can be joined a few ways. Transformer vector group free download as powerpoint presentation. Vector group test of power transformer electrical4u. How to draw vector group of transformer from winding. Transformer windings can be connected in several ways. The vector group also defines differences in phase angles between them. Sep 26, 2017 the vector group transformer test is important for connecting two power transformer in parallel. The transformer vector group show the phase difference between the primary and secondary sides of the transformer.
A three phase transformer is one of the vital apparatus in the power systems. In a current transformer, if we double the turns in the primary, what happens to the secondary current. With regards to the protection circuit, you will need the vector group information in order to decide how you will wire the current transformers or if you are using numerical relays, what compensation will you need to apply. If two transformers of different vector groups are connected in parallel then phase. Vector grouping of three phase transformer part 1 duration. The three phase transformer windings can be connected several ways. How to determine transformer vector group a vector group is the international electrotechnical commission iec method of defining high voltage hv and low voltage lv winding configurations of threephase transformers. If two transformers of different vector groups are connected in parallel then. 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. To understand the designation of these groups one has to know the assumptions. 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. This symbol indicates the winding connections and their relative phase displacement by means of a numerical index e.
Threephase transformer connections and vector groups for. Vector groups pdf transformer electric power free 30. Why do we need to define a vector group in a transformer. Vector grouping of a three phase transformer part1. In a 3 phase transformer, if the primary high voltage and secondary low voltage side windings are connected in delta star, the phase. The determination of vector group of transformers is very important before connecting two or more transformers in parallel. What is meant by vector group for transformers and why is. Transformer is the most important unit in an electrical distribution network. What is the meaning of transformer vector group yna0d1. A user friendly simulation for transformer vector group. Significance of vector group of transformer your electrical. 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.
Transformer vector group what is yd11 etc easy explanation. Importance and elimination of third harmonics application and selection of vector group of transformer. Understanding transformer vector groups valence electrical. From a vector group one can determine the phaseshift between primary and secondary. 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. What is meant by vector group for transformers and why is it. Vector groups are the iec method of categorizing the primary and secondary winding configurations of 3phase transformers. Every transformer contains its own vector group as shown below figure. 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. Dv power smart test instruments for reliable electrical.
Liggett group llc founded in 1873, liggett group llc is the fourthlargest cigarette manufacturer in the u. The nameplate shows what the factory thought as the most probable vector group, but any dy or yd transformer can have any of the odd numbered vector groups. Why vector group of distribution transformer is dyn11. Dv power qualified engineers will gladly assist you during measurements or answer your technical questions from different areas of the electrical power market.
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