From High Voltage Engineering and Testing, 2nd Edition

J.A. Lapworth

14.1 Introduction

Transformers are required to transform the power output from electrical generators up to the voltages used in the transmission system (400 and 275 kV in the UK), to interconnect parts of the transmission system and to step down the voltage at bulk supply points and at various points in the distribution network before reaching the consumer. In addition, special transformers are required for AC/DC convertor stations and for transmission control devices such as quadrature boosters and static VAr compensators.

For a utility, large power transformers are major capital items, costing up to 2M, with construction lead times up to 18 months. Although generally very reliable, when problems occur they are often difficult to diagnose and expensive to correct. For example, just to handle the oil from a transformer to allow an internal inspection, which very often can be inconclusive, can cost over 10 000 for a large transformer.

A utility is therefore concerned, as a customer, to ensure that as far as possible every new transformer purchased is capable of performing to requirements and will continue to do so for a service life of at least 40 years, over the specified operating conditions and without being damaged by the inevitable occasional system abnormalities. The user requires a transformer which will be effective, efficient, reliable and also economical. Key activities in ensuring this are the specification for the transformer, quality assurance during manufacture, effective testing of the transformer before it leaves the manufacturer's works, and appropriate maintenance...

Products & Services
Single Phase Transformers
Single-phase transformers output single-phase AC power, typically while stepping-up or stepping-down the voltage between two circuits.
Transformer Repair Services
Transformer repair services offers repair, upgrades, or design modifications for transformers.
Transformer Winding Services
Transformer winding services design transformers and other magnetics products for application-specific and OEM usage in a variety of industrial, medical, military, aerospace, telecommunications, commercial and specialty applications. 
Transformer Test Equipment
Transformer Test Equipment consists of specialized test modules or systems used to test and/or monitor electrical and mechanical parameters of transformers and other related devices.
Board Mount Transformers
Board mount transformers are transformers designed to be embedded in or mounted on computer boards.

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