ABB’s TEC system optimises power transformer performance and extends service life

ABB’s new TEC (Trafostar Electronic Control) system is designed to help utilities maximise the return on their investment in power transformers by keeping them operating at peak performance over a long service life. In addition to providing the detailed real-time knowledge of a transformer’s ‘state of health’ essential for condition-based maintenance programmes the TEC system can also intervene operationally. In effect, TEC creates an intelligent Industrial-IT enabled transformer capable of making decisions and recommendations based on available data, to control its cooling system for example or to adjust the tap-changer voltage.

As utilities place an ever increasing focus on ‘asset management’ and ‘remaining life management’ there has been a corresponding trend to equip transformers with monitoring devices. However, conventional systems are essentially passive in that they are not capable of controlling the transformer. Instead, they require engineers to spend a great deal of time sorting and interpreting the information they receive. The strength of the TEC system is that it collects all the data it requires for transformer control from just a few multi-purpose sensors and transmits a constant stream of information over a single fibre-optic link back to the substation control room.

To achieve the goal of making power transformers intelligent and maintenance free, ABB has created a common electronic interface which exchanges information with key systems including: the monitoring and diagnostic devices of the transformer and components; the transformer control cabinet; the tap-changer motor-drive; the voltage regulation system; the overall protection system. Through this interface, TEC provides exact status information to enable utilities to extend transformer lifetime and save costs by reducing maintenance and increasing availability.

Transformer model
TEC works by generating a computer model of the transformer and its working conditions and then comparing the measured parameters with the simulated values. Discrepancies are detected and potential malfunctions and/or normal wear in the transformer and its ancillaries are indicated. The availability of real-time information also opens up new possibilities for optimising operation and maintenance. For example, TEC can direct the cooling system to ensure different fans are used in rotation, switching coolers to manage usage, wear and efficiency. It can also control and adjust tap-changer voltage.

TEC is now being delivered with all new ABB power transformers.