Traction Transformers – "Tractronic®"

The perfect transformer for every vehicle

Siemens Energy designs and manufactures Tractronic® traction transformers for rail operators and train manufacturers worldwide, that increase train efficiency and performance, handle maximum ratings in a minimum of space, serve local content demands for worldwide applications, and ensure maximum reliability and flexibility.

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With over a century of experience in transformer technology, Siemens Energy is one of the world’s leading suppliers for customized, state-of-the-art railway transformers. The secret to Siemens Energy stellar track record is a refined system of global logistics, internationally binding quality standards, highly trained skilled workers and specialization.

Compact, light and efficient

Siemens Energy develops and produces traction transformers for rolling stock applications of all relevant ratings and voltage levels. The focus is on maximum reliability, economic efficiency and safety – and ensuring that the transformers are perfectly in line with the customer’s requirements.

Siemens Energy offers single-phase and multi-phase units in all capacity ranges up to 15 MVA and – upon customer request – even above. Units can be mounted in machine rooms, under-floor and low-floor applications, and for on-roof installation.

Siemens Energy builds traction transformers with frequencies from 16 ⅔ to 60 Hz and rated power up to 15 MVA. Operating voltages include 1.5 kV DC, 3 kV DC, 12 kV, 15 kV, 25 kV as well as special voltage levels.

Siemens Energy can design and customize the cooling unit to suit customer preferences, either integrated in the transformer in the full frame or as a separate component, entirely in accordance with the specific space requirements. Flexibility is also the order of the day when it comes to selecting cooling fluids. We have solutions for all capacity ranges that use oil, silicon, or an ester-based fluid (e.g. MIDEL 7131) that is very kind on the environment.

For its traction transformers, Siemens Energy offers integrated smoothing and filter reactors; auxiliary and heating windings, depending on customer specifications; and traction windings as network filter reactors.

Leveraging data for maximum transformer performance

Siemens Energy transformers offers the opportunity to track the transformers in operation. Operators can not only monitor but optimize transformer performance. Monitoring and data analysis are the important factors for digitalization of traction transformer for rollingstock applications.

A modular multisensory system continuously monitors the “health” status of the transformer and modifies operation behavior according to the results of an onboard optimization algorithm. The Siemens Energy monitoring system leverages a new generation of sensors. These sensors transmit data to a local, remote or cloud-based control system. After data processing, the actors will – if necessary – receive commands for correcting the operation behavior.

Economical and technical information of each traction transformer is updated online and collected to optimize all similar transformers in operation. Our real-time monitoring system optimizes cost of operation cost and maintenance intervals, increasing energy and economic efficiency.

Rely on Siemens Energy Transformers – anywhere, anytime

Siemens Energy traction transformers operates a worldwide manufacturing and service network to serve customers all over the world. Our manufacturing sites worldwide adhere to European quality and sustainability standards – regardless of the manufacturing location.

  • trustful and responsible partner with solid installed base worldwide,
  • state-of-the art transformers technology,
  • tailored solutions for customer’s requirements,
  • comprehensive service offering directly on-site

This ensures that customers can rely on Siemens Energy traction transformer, components and services, anywhere, anytime.

Developed, tested and certified

Siemens Energy traction transformers are setting standards of quality and versatility around the world. Close cooperations with international standards committees guarantee the compliance with the specific requirements and standards.

Our railway components comply with all the relevant standards, for example: DIN, EN, IEC, IEEE, ISO, EAC / GOST and ANSI, as well as the current fire protection standard EN 45545. With our certified components, we actively support the worldwide vehicle approval process; hence our traction transformers comply with all relevant standards, for example:

  • ISO 9001
  • ISO 14001
  • ISO 45001
  • ISO 22163 (IRIS)
  • Welding qualification EN 15085-2

Tests for maximum reliability and customer satisfaction

Siemens Energy uses the most advanced and comprehensive routine tests, type evaluations and special tests for maximized product reliability and customer satisfaction. Siemens Energy traction transformers are tested essentially in the same way as power transformers to ensure maximum safety and quality. Upon request, tests may be performed at an accredited third-party laboratory.

• Routine tests on each traction transformer acc. to EN 60310

• Type tests acc. to EN 60310

• Finite element method (FEM) of eigenfrequencies and stiffness

• Shock and vibration test for traction transformer acc. to IEC 61373

• Short circuit test acc. to DIN EN/ IEC 60076-5

• Measurement noises acc. to EN 60076-10

• EMV investigation and special tests

Turning energy into speed

On-board Tractronic® traction transformers turn energy into speed that moves passengers and freight. As part of the traction chain, they are crucial to the performance of train and operator services. Siemens Energy designs and builds Tractronic® traction transformers in different specification profiles: Frequency, rating and voltage; Required dimensions and weights; Losses and impedance voltage characteristics; Operational cycles and frequency response behavior; Environmental requirements.

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Make use of our services

For your convenience, we have gathered relevant downloads in one spot. If your question is still unanswered, please feel free to contact our Energy Support Team.    

Brochure downloads

Tractonic: Traction Transformers
PDF (4 MB)

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Siemens Energy complies with the laws and regulations affecting traction transformers

Siemens Energy is closely monitoring the development of transformer regulations worldwide e.g. European Eco Design Directive and US DOE rules. Siemens Energy adheres to the rules and regulations communicated e.g. in US and Europe and complies with all relevant requirements for every transformer product delivered. As a trustful and responsible partner Siemens Energy understands the importance of these regulations and will continue to monitor potential future requirements. We will continue to adapt and comply with all relevant regulatory changes.