Transformer intelligence taken to the next level
Published: 03 March, 2016
ABB’s smart, sensor-based Transformer Intelligence technology enables utility and industrial customers to optimise and manage power transformers. The solution based on ABB’s CoreTec online monitoring and CoreSense sensors provides real-time monitoring of mission-critical functions for transformers rated from 11 kV to 400 kV.
The CoreTec online monitoring system keeps a close watch on a transformer’s mission-critical functions and performs a complete evaluation of its operating conditions. Through advanced algorithms, online data can be simulated and forecasted to provide information on how transformer usage can impact on transformer lifetime, enabling predictive maintenance.
The CoreTec system is modular and expandable to suit the transformer operator’s current and future requirements. It is also maintenance free for up to 15 years, thanks to robust and proven components.
With its compact size and minimised cabling, ABB says CoreTec is easy and fast to install
on both new and retrofit applications since only a few sensors are required, and can be installed on any type and brand of transformer. The unit is easy to operate and displays a large number of operational parameters via a user-friendly and secure web interface.
CoreTec offers the capability to include over 30 parameters including: Load and peak load, top and bottom oil temperature, gas and moisture in the transformer
oil, tap changer position. It also provides DNP3 as well as IEC 61850 communication.
A particular advantage of CoreTec, explains ABB, is the predictive loading capacity that offers improved control and greater assurance of the load capability of the transformer. If the overload capacity function is used then it is possible to safely operate an air cooled transformer at an overload of between 10-30% for a defined period of time.
Traditional transformer condition analysis techniques such as laboratory Dissolved Gas Analysis (DGA) is a very effective method for detecting incipient transformer faults.
The drawback is that it can only provide intermittent information relating to the time that the oil sample was taken. That is why ABB has developed the new CoreSense sensor to provide real time transformer intelligence, online and all the time.
CoreSense continuously monitors hydrogen levels in transformer oil to provide an early warning for most incipient transformer faults. In addition to hydrogen, it can also continuously monitor moisture levels. Moisture can compromise the insulating properties of oil and accelerate the aging of transformers. ABB has vast transformer experience to recommend corrective actions based on hydrogen and moisture readings obtained from CoreSense.
CoreSense is easy to install and use. Thanks to its thermal pump design that uses no moving parts it can be connected to the transformer at any location including the drain valve. The thermal pump induces a convection flow by heating the oil, thus causing fresh oil to be pulled in. This solution eliminates the need of having any moving parts, such as a mechanical pump that can be prone to failure. The sensor can be installed on any transformer – new or old, regardless of brand, type or location.
It is designed for 15 years of maintenance free operation. This is the result of its heavy duty industrial grade design with an all metal enclosure and no moving parts, so there is less maintenance, no consumables and many years of trouble free operation.
A complement to laboratory analysis
CoreSense is not intended to replace offline laboratory transformer oil analysis, but
rather to complement it. ABB works with a leading test laboratory to provide TCA
(Transformer Condition Assessment) that offers a comprehensive assessment of
the dielectric and mechanical state of the transformer including:
• Routine tests for moisture, acidity and dielectric breakdown
• PCB levels
• DGA (Dissolved Gas Analysis)
• Furan analysis
CoreTec and CoreSense are designed to be connected to ABB Asset Condition intelligence Solutions (ACi) that provide a fleet condition dashboard with asset reliability and associated recommendations to mitigate risks.
For further information please visit: www.abb.com
