5 MVA Traction Power Transformer-22/6.6 kV | South Africa 2025

Maximize Your Drive Train Efficiency. Start with the Traction Transformer.

01 General

1.1 Project Description

5 MVA traction power transformer was delivered to Canada in 2025. The rated power of the transformer is 5000 kVA with ONAN cooling. The primary voltage is 22 kV with ±2*2.5% tapping range (NLTC), the secondary voltage is 6.6 kV, they formed a vector group of Dyn11.

In response to the lightning conditions (12 ground flashes per square kilometer per year) and severe salt spray and industrial soot pollution in South Africa, its design fully considers insulation protection and corrosion resistance. The fuel tank is made of steel plates with a thickness of ≥6mm, and the bottom plate thickness reaches 16mm. The coating thickness in heavily polluted areas is 125 microns. Moreover, the fuel tank and radiator adopt a matching welding design to ensure structural strength and sealing performance.

In terms of core functional configuration, the traction power transformer is equipped with an NLTC no-load tap-changer, supporting a voltage regulation range of ±2×2.5% and featuring padlockable functionality to ensure accurate and safe voltage regulation. The low-voltage winding can withstand a total voltage harmonic distortion of up to 27%, adapting to complex power grid environments. The winding has sufficient mechanical strength to resist fault currents, and the live part has a ground clearance of 3500mm, complying with high-voltage safe operation standards. Meanwhile, the equipment is equipped with multiple protection devices, including a single-float gas relay (with alarm and trip contacts), an overload thermal relay (with ambient temperature compensation, trip temperature set at 115℃), a dial-type oil surface thermometer (adjustable contact set at 90℃), and a pressure relief valve, which can monitor the operating status in real time and respond to abnormalities quickly.

1.2 Technical Specification

5000kVA traction power transformer specifications type and data sheet

1.3 Drawings

5000 kVA traction power transformer diagram drawing and size.

02 Manufacturing

2.1 Core

The transformer core is the central magnetic circuit of a traction transformer. Constructed from high-permeability silicon steel laminations, it efficiently channels alternating magnetic flux with minimal energy loss. This is critical for reliable power conversion and stable operation under the demanding conditions of railway transportation.

2.2 Winding

The continuous disc winding is a key coil type in traction transformers. It is formed by winding rectangular conductors in a series of radial discs without soldered joints between turns. This robust mechanical structure provides exceptional short-circuit strength and efficient heat dissipation, which are vital for reliable operation under frequent load fluctuations.

2.3 Tank

The tank serves as the protective enclosure and integral cooling system for the traction transformer. It is mechanically robust to withstand vibrations and impacts, while its design optimizes heat dissipation to ensure the core and windings operate within safe temperatures, guaranteeing reliability under demanding service conditions.

2.4 Final Assembly

Final assembly is the critical process of integrating the core, windings, and tank into a complete and reliable traction transformer. It ensures precise mechanical alignment, electrical integrity, and oil-tight sealing, resulting in a robust unit capable of delivering specified performance under the demanding conditions of railway operation.

03 Testing

This traction power transformer has undergone a comprehensive series of routine, type and special tests to validate its electrical integrity, operational efficiency, and long-term reliability. The rigorous testing regimen, covering dielectric strength, losses, ratio, insulation, and gas-in-oil analysis, confirms the unit’s full compliance with performance specifications and its readiness for demanding railway service.

04 Packing and Shipping

4.1 Packing

The packaging of the traction transformer is engineered for maximum protection during transit and storage. Utilizing a robust, weatherproof framework with customized bracing, it ensures the integrity of the unit against mechanical shocks, vibrations, and environmental factors, guaranteeing safe arrival at the installation site.

4.2 Shipping

The shipment of this traction power transformer is executed under CIF (Cost, Insurance, and Freight) terms, providing a comprehensive port-to-port logistics solution. Our responsibility encompasses the entire process of delivering the unit safely to the Port of Durban, South Africa. This includes managing export customs clearance, securing the core ocean freight service, and arranging full cargo insurance, with all associated costs covered. This approach offers the client significant certainty and risk mitigation, ensuring that the critical equipment is professionally managed by us throughout the international sea transit until its discharge at the destination port.

05 Site And Summary

At the core of the power world, stability and efficiency are eternal pursuits. Our traction transformers are not only precise devices that convert electrical energy into powerful force, but also the cornerstone that carries safety, punctuality and trust. From the initial design concept to the final strict testing, our relentless pursuit of excellence in every detail is solely to ensure that in every start-up and every journey, we can provide silent yet powerful support.

Choosing our products means you have selected a trustworthy long-term partner. We promise to drive the future of modern transportation together with you through outstanding technology, reliable quality and all-round services, making every connection full of power.