Special transformers — traction, 12–36-pulse rectifier, furnace, unit, booster and railway autotransformers up to 66 kV, 100 MVA

Description

Special transformers are built for specific applications using liquid-filled (oil) technology. The range covers unit transformers for industrial plants and petrochemical works, rectifier transformers for traction systems with 12-, 24- and 36-pulse schemes, and traction power supply transformers. It also includes autotransformers, notably for railway autotransformer feeding systems, trackside booster transformers, furnace transformers, system inter-tie transformers and transformers with two secondary windings.

The voltage class is up to 66 kV and the through rating is up to 100 MVA. The design is inherited from the power transformers of the same manufacturer. Efficiency meets the Tier 2 level under EU Regulation 548. For environmentally sensitive and urban sites, alternative liquids Midel and FR3 are available. Low-noise core stacking and variable-speed fans reduce noise, and the insulation has minimal partial discharge.

Cooling ranges from natural to directed oil circulation and forced air. Voltage is regulated by an OLTC (externally mounted or built in) or an off-circuit tap changer with remote control panels. For monitoring there are fibre-optic temperature sensors and gas analysis. Manufacture follows ENATS, IEC, ANSI, Shell DEP, Aramco and railway specifications, adapted to customer requirements. The design is agreed with the site conditions. The compact design reduces the substation footprint and civil works costs. The company has many years of experience supplying such versions, and design solutions are carried over from its main range of power transformers.

For DC traction systems, high-speed DC circuit breakers (Lightning, PowerBond) are supplied alongside rectifier transformers, which makes it easier to assemble a traction substation. Applications include railway, metro and tram traction substations, petrochemicals and oil and gas, metallurgy and industrial drives. Installation, commissioning and lifecycle service are carried out by certified engineers, including a round-the-clock service.

Transformers are fully assembled and tested at the factory in Loughborough (United Kingdom). The test facility, which complies with IEC (BS EN) and ENA, performs routine and type tests up to 170 kV, including impulse, temperature rise, SFRA, and measurement of partial discharge, losses and noise level.

Technical specifications

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