Autotransformer
A transformer with a single winding acting as both primary and secondary, providing voltage conversion through electromagnetic induction and direct electrical connection.
An autotransformer is a type of electrical transformer with a single winding that has at least three taps. Unlike a conventional two-winding transformer, it shares part of its winding between the primary and secondary circuits, resulting in a more compact and cost-effective design for voltage ratios close to 1:1.
Autotransformers are widely used in power transmission for voltage interconnection (e.g., connecting 132kV to 33kV systems), motor starting (reduced-voltage start), and voltage regulation in distribution networks. They offer advantages of lower cost, smaller size, and higher efficiency compared to two-winding transformers of equivalent rating.
However, autotransformers do not provide electrical isolation between primary and secondary, which limits their use in applications where safety isolation is required. QDTB manufactures autotransformers for industrial voltage conversion, motor starting, and grid interconnection applications. See our transformer selection guide for help choosing the right configuration.
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The total power in an AC circuit combining real (active) and reactive power, measured in kilovolt-amperes (kVA).
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A heavy-duty transformer designed to supply power to electric arc furnaces used in steelmaking and metal smelting.
ANSI C57
The American National Standards Institute standard series covering power transformer requirements for the North American market.
Amorphous Alloy Transformer
A distribution transformer using amorphous metal core material achieving 60-70% lower no-load losses than conventional silicon steel cores.
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Amorphous Alloy Transformer
A distribution transformer using amorphous metal core material achieving 60-70% lower no-load losses than conventional silicon steel cores.
Box-Type Substation (Prefabricated)
A factory-assembled compact substation integrating transformer, HV/LV switchgear, and protection in a weatherproof enclosure.
Cast Resin Dry-Type Transformer
A dry-type transformer with windings encapsulated in epoxy resin for fire safety and moisture resistance indoors.
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