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CPM Scheduling,
Basic Engineering,
and Project Approach for Typical Substation EPC
Substation Power Transformers
The substation power transformers transform one nominal level system voltage to
another. The power transformers must carry the system power flow under various
operating conditions and contingencies. Power transformers are the largest, heaviest,
and very costly piece of equipment used in substations. There are two types of power
transformers, autotransformer and multiwinding conventional transformers. A three-
phase power transformer installation can be a three-phase unit or three single-phase
units.
Figure 3-1, 3-2, and 3-3 shows the power transformer, three-phase transformer with
tertiary and three-phase Auto-Transformer.
Figure 3-1: Power Transformer
(Shown with Load Tap Changer on Low-Voltage Side)
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Dewan Jamir EMGT 835, Spring 2006
Figure 3-2: Three-Phase Transformer with Tertiary
Figure 3-3: Three-Phase Auto-Transformer