In general all transformer vector groups with a wye on the secondary side are acceptable for the use in combination with trio inverters, while in particular the primarydeltasecondarywye arrangements with vector group dyn11, dyn5 or dyn1 are those that most commonly have been specified for our applications. Significance of vector group of transformer on the nameplate of threephase transformer vector group is printed as yy 0, dd 1 etc. Transformer vector group transformer voltage scribd. 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.
Rphase hv and rphase lv shorted for all vector group of transformer. But after the winding connection is made it is necessary to check if the desired vector group has been achieved. 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. It is likely that the voltage in the tertiary winding is lv, hence d11 not d11. A three phase transformer is one of the vital apparatus in the power systems.
Vector group of 3phase transformer electrical concepts. When we energized the transformer its tripped suddenly due both earth point close circuits. The vector group designation indicates the windings configurations and the difference in phase angle between them. 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 test of transformerthe vector group of transformer is an essential property for successful parallel operation of transformers.
The connection of all the windings in a threephase transformer is indicated by a vector group symbol. So it is utmost necessary to know how the inter connections to be made to form a particular vector group. The vector group of transformer is the phase difference between the primary and the secondary sides. The three phase transformer windings can be connected several ways. Aim of vector group test is at site is to check if their is any damage in the windings during transportation and erection. There is no technical difference between the one vector groups i. 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.
Based on the windings connection, the vector group of the transformer. We have transformer of dyn11, if we change the phase sequence can transformer vector group change. You can only upload files of type 3gp, 3gpp, mp4, mov, avi, mpg, mpeg or rm. Vector group test of transformer the vector group of transformer is an essential property for successful parallel operation of transformers.
Will it make any difference as far as the vector group is concerned if instead of phase a and c, phase b and c were swapped on both ends of the transformer. Vector groups pdf transformer electric power scribd. Vector group is punched on the name plate based on the user requirement by the manufacture. Transformer nameplates carry a vector group reference such at yy0, yd1, dyn11 etc. All transformers are subjected to various tests at the manufacturer. For each vector group need diffrent type of voltage combination to conform. Applicationnote how to determine transformer vector group. Yes, the name plate vector group of a transformer is only valid for a standard phase rotation abc. One procedure of vector group testing of transformer is explained as. Based from this, we can say that this transformer connection belongs to the vector group ynd11. Understand significance of vector groups interpret the vector group notations used on transformer name plates content.
Vector group test of transformer is done for detecting the vector group. The transformer vector group show the phase difference between the primary and secondary sides of the transformer. Based on the windings connection, the vector group of the transformer is determined. Vector group is an essential characteristics of 3 phase 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. Primary and secondary must be star, with zero vector group phase shift, because there is no other way to use auto transformers on 3 phase. Transformer vector group free download as powerpoint presentation. Three phase transformer vector grouping significance. Transformer vector group the vector group test is importent test in the transformer testing. How do you design vector group of transformer answers.
Transformer vector group free download as word doc. For q1, there is no way to determine the vector group on a oneline diagram except when explicitly labled. For the love of physics walter lewin may 16, 2011 duration. Vector group test of power transformer electrical study. 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. 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. With the wye side as the reference vector at 12 oclock, we can draw the delta side vector at 11 oclock. The vector group transformer test is important for connecting two power transformer in parallel. For example, a wye hv winding and delta lv winding with a. Pdf transformer vector group test conditions k pandian.
Two of them are in range of normal skewness value i. Vector group test of power transformer electrical mastar. Transformer connections from the same group can be. Autotransformer vector group cr4 discussion thread. Here yy 0 will mean its both the windings are starconnected and phase displacement between primary and secondary emfs is zero degree. The transformer vector group is indicated on the name plate of transformer by the manufacturer. Transformers connected in parallel must have the same vector group. Export graph images to pdf, jpeg, eps, and more origin. Measure the voltages in various combination on both side of the transformer hv lv. Every transformer contains its own vector group as shown below figure. Transformer vector group connections are made based on the winding polarity. 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.
It means lv winding,which is star connected written in small letters means lv. A user friendly simulation for transformer vector group. Contents hide 1 basic idea about transformer vector group 1. This video outlines the vector groups that you will come across on a typical transformer and explains the principles of phase shift, and is a. This symbol indicates the winding connections and their relative phase displacement by means of a numerical index e. The clock method is used to produce the numerical index of the vector group.
In electrical engineering, a vector group is the international electrotechnical commission iec. What is meant by vector group for transformers and why is. The real time examples for phasor groups of transformer are given here. The action of a transformer is a particular case of the principle of mutual inductance, and a transformer consists essentially of two windings, the primary and secondary on a common magnetic core. Vector group of transformers free download as powerpoint presentation. Vector group test of power transformer electrical4u. How to draw transformer vector group connectionelectrical. In addition to the voltage ratios and kva ratings, one of the most important specifications is the transformer vector group. In other words, the vector group gives information about the connection of the tertiary winding. Importance and elimination of third harmonics application and selection of vector group of transformer. Please note that u cannot have two different vector group on a single transformer,i. 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. 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. Transformer vector group what is yd11 etc easy explanation.
These tests are done when the tap of transformer is nominal. It also determines the high voltage and low voltage windings arrangement of three phase transformers. Transformer what is the meaning of dyn11 in a transformer. A vector group is a method of specifying a threephase transformer or transformer bank method of connection and its angular displacement. Pdf to jpg online converter convert pdfs to jpg images for free. What is the meaning of transformer vector group yna0d1. Easily convert pdf to jpg with this free online converter. Transformer vector groups can be a difficult concept to understand. Note that when determining the angle between h1 and x1, the rotation must be clockwise. On the name plate of a three phase transformer, the vector group.