So nomally star delta starter is used for induction motor. 20 kV to the local transformer which has a delta primary and wye / star secondary. General Electric power transformer nameplate (50 MVA Substation Power Transformer with Load Tap Changer). Figure 1 - Transformer Connection - Star-Delta. Electrical Tutorial about the Three Phase Transformer Connections and Basics, Three Phase Transformer Windings including Star and Delta Configurations.


Author: Natasha Howe
Country: Gambia
Language: English
Genre: Education
Published: 27 November 2016
Pages: 136
PDF File Size: 42.98 Mb
ePub File Size: 45.59 Mb
ISBN: 929-6-21776-904-1
Downloads: 8604
Price: Free
Uploader: Natasha Howe

Download Now

Figure 1 — Transformer Connection — Star-Delta The voltages on primary and secondary sides can be represented on the phasor diagram as shown in the Figure 2 below.

Delta-wye transformer - Wikipedia

Hence fewer numbers of turns are required. This makes the connection economical for large high voltage step down power transformers. The neutral available on the primary can be earthed to avoid distortion. This can star delta connection transformer problems when paralleling 3-phase transformers since transformers secondary voltages must be in-phase to be paralleled.

Star-Delta Transformer Connection Overview

Therefore, we must pay attention to these shifts. If secondary of this transformer should be paralleled with secondary of another transformer without phase shift, there would be a problem Application: It is commonly employed for power supply transformers.

This type of connection is commonly employed at the substation end of the transmission line. Star delta connection transformer advantages I've seen are usually related star delta connection transformer how you want the phases referenced to something else.

One advantage of Y is that you get a way to symmetrically reference all three phases to the same voltage usually earth. This feature enables proper coordination of protective devices and is a very important design consideration.

The neutral of the Y grounded is sometimes referred to as a grounding bank, because it provides a local source of ground current at the secondary that is isolated from the primary circuit. The magnetizing current must contain odd harmonics for the induced voltages to be sinusoidal and the third star delta connection transformer is the dominant harmonic component.


In a three-phase system the third harmonic currents of all three phases are in phase with each other because they are zero-sequence currents. In the Y-Y transformer connectionthe only path for third harmonic current is through the neutral.

Delta-Star Transformer Connection Overview

The same thing is true for the other zero-sequence harmonics. It can be a single three-phase transformer, or built from three independent single-phase units.

The nuetral available on the primary can be earthed to avoid distortion.

The neutral point allows both types of loads single phase or three phases to be met.

Related Posts ...