Fit at 50: Keeping aging transformers healthy for longer with ABB TrafoAsset Management

THOMAS WESTMAN, PIERRE LORIN, PAUL A. AMMANN – Keeping fit and “staying young” are goals for many – including power transformers. Many of the world’s transformers are reaching an age where these goals are becoming critical for their survival, and for the survival of the operating companies. The consequences of a transformer failure can be catastrophic. This is why operators demand high availability and a rapid recovery time after an outage. With an aging fleet of transformers and tight maintenance budgets, transformers remain in service well past their optimal life spans. The assumption that all are fi t for an extended working life can be a dangerous gamble. When it comes to transformer asset management, an operator’s main objectives are to reduce the risk of a failure and minimize the impact if a failure does occur. ABB’s TrafoAsset ManagementTM provides just the support operators need to make intelligent maintenance decisions to face these challenges.

Power transformers, which are often the most valuable asset in a substation or plant, are indispensable components of high-voltage equipment for power generation plants, transmission systems and large industrial plants. Unexpected failures cause major disturbances to operating systems, resulting in unscheduled outages and power delivery problems. Such failures can be the result of poor maintenance, poor operation, poor protection, undetected faults, or even severe lightning or short circuits 1,2. Outages affect revenue, incur penalties and can cost a company its reputation and its customers. The Institute of Nuclear Power Operations stated in 2002 that more than 70 events had been associated with large, main auxiliary or step-up power transformers (since 1996) [1]. Significant station impact occurred during several events and in addition over 30 reactor scrams (ie, emergency reactor shutdowns) as well as plant shutdowns and reductions in power delivery were associated with transformer events. The result: in many cases, lost production and expensive repairs. The enormous costs of power transformer failures provide ample incentive for electric companies to ensure reliability and availability throughout the life cycle of these key assets. Transformers cost anywhere from $2 million to $4 million, and on the rare occasions they do fail, the financial impact can be even more significant – in extreme cases, they can leave a company facing financial ruin 3. In addition, as most countries have strict laws in place that control and regulate power supply, non-delivery penalties can be as high as 100 times the price of the energy itself.