AS TET ESTEL

TET Estel provides advanced rectifier and inverter systems for traction substations in both mainline railway and urban transport applications.

Our solutions are designed for high reliability, long service life, and stable operation under demanding railway conditions. Natural and forced cooling technologies are applied to ensure efficient heat dissipation, high overload capability, and maintenance-free operation.

Rectifier systems are available in 6-pulse and 12-pulse configurations and can be adapted to various topologies, including single or double bridge designs and reverse star configurations with current-balancing reactors. The design incorporates optimized busbar arrangements and shared heatsink solutions to minimize losses and reduce the number of electrical connections.

A key feature of our systems is the use of custom-designed clamping mechanisms, allowing fast and safe replacement of diodes without dismantling the equipment or using special tools.

Each semiconductor device is equipped with a conductivity monitoring circuit, enabling continuous diagnostics and ensuring high operational reliability. The systems are integrated with TET Estel’s proprietary microprocessor-based control units, featuring advanced protection, real-time monitoring, and data logging capabilities.

Measured parameters such as current, voltage, temperature, and waveform characteristics are continuously recorded and can be analysed for predictive maintenance and system optimization. Operator interfaces include intuitive control panels with LCD displays.

Inverter systems are designed with robust thyristor assemblies, flexible busbar connections to compensate thermal expansion, and precise control based on real-time measurements using Hall effect sensors.

All solutions are developed in compliance with RoHS and REACH requirements.

TET Estel develops and supplies power conversion systems for electric and diesel locomotives, ensuring efficient traction control, energy savings, and long-term operational reliability.

Our rectifier-inverter units are widely used in mainline electric locomotives, including high-power platforms. These systems enable contactless traction control, significantly increasing equipment lifetime and reducing mechanical wear.

The application of our converter solutions allows:

• up to 12% increase in locomotive traction performance
• up to 15% reduction in energy consumption
• improved overall efficiency and operational stability

For diesel locomotives, TET Estel offers rectifier systems designed to convert generator AC into controlled DC power with independent voltage regulation for each traction motor. This ensures precise control of traction modes and enhances locomotive performance under varying load conditions.

The systems also support electrical braking in generator mode, controlled by a microprocessor-based system. An emergency operating mode is allowing the converter to function as an uncontrolled diode rectifier and enabling the locomotive to continue operation until maintenance can be performed.

All solutions are based on TET Estel’s proprietary control systems and are designed to comply with RoHS and REACH requirements.

TET Estel offers complete turn-key solutions for traction substations and railway power supply systems, covering all stages from design and equipment supply to installation and commissioning.

Our integrated approach ensures full compatibility of all system components, optimized performance, and reduced implementation time.

A typical solution may include:

• Diode rectifier units (6-pulse or 12-pulse) with control systems
• Rectifier transformers and auxiliary transformers
• AC switchgear (6 kV / 10 kV)
• DC switchgear (e.g. 600 V)
• Auxiliary power supply systems
• Control and telemetry cabinets
• Spare parts kits

Depending on project requirements, the solution can also include:

• Heating, ventilation, and air conditioning systems
• Security and fire alarm systems
• Containerized solutions for equipment installation
• Power and signal cables

TET Estel also provides installation, supervision, and commissioning services, ensuring reliable system start-up and long-term operation.

Our turn-key solutions are designed to meet the highest industry standards and can be tailored to specific customer requirements and project conditions.

TET Estel designs and manufactures a wide range of power semiconductor devices, including thyristors and diodes in disc, stud, and module designs for high-power and demanding applications.

Our devices are developed for use in railway systems, traction substations, industrial converters, and other heavy-duty power applications where reliability and performance are critical.

The product portfolio includes:

• Phase control and fast thyristors
• Rectifier, fast recovery, and avalanche diodes
• Devices optimized for high current and high voltage operation

TET Estel semiconductors are engineered to deliver stable performance under real operating conditions, including high thermal and electrical loads. Special attention is paid to minimizing losses, improving thermal management, and ensuring long service life.

Our devices support parallel and series connection and are designed for applications requiring high surge current capability, resistance to electrical and thermal cycling, and stable switching characteristics.

We also develop application-specific solutions, including devices with unique combinations of parameters tailored to customer requirements and replacement of components from other manufacturers.