Keeping the Lights On: Building Transformer Resiliency with Condition Monitoring
Recent supply chain disruptions have led to a shortage of raw materials needed for transformer production and repair. A lack of working transformer units puts the nation’s electric infrastructure in jeopardy. The severity of this led President Biden to sign an executive order in June 2022, to fast-track the domestic production of transformers and other clean energy technologies to modernize and strengthen the power grid. As the industry undergoes this rebuilding phase, it’s critical to maintain the quality of these assets from production to the end of its lifecycle.
Nature’s Attack on Power Grids
While the older power grids are weakening and breaking down, the presence of extreme weather is affecting even the newer transformers. This severe weather, combined with other natural disasters like earthquakes and floods, continue to pose a threat to power grids. This weather is unavoidable; climate change has and will continue to exacerbate these events, and the power grid needs to be prepared. Building a more resilient power grid is important, but maintaining the transformers we already have is essential. Over 50% of transformer failures are caused by external factors such as weather-related events. If the unit is already weak and overly stressed, there’s a greater chance that the presence of these elements will cause the unit to fail. Condition monitoring tools detect issues early to help better prepare these units for unexpected events.
Microgrids: The New Way Forward for Renewable Energy
Transformers are the backbone of the power grid, but the recent gradual shift to microgrids has the utilities world excited. Microgrids are smaller, interoperable with the electric grid, and overall easier to construct and maintain. That’s not to say transformers will be making a permanent exit, but microgrids are an excellent way to integrate more manageable grids into the electrical landscape. Their recovery is much faster after a large weather-related incident, and their repairs much easier. Microgrids are a great renewable option as the world focuses on mitigating climate change. The quick acting grids operate independently to conserve energy and reduce transmission losses, but can also connect to the larger grids to provide additional support when needed.
Starting Fresh and Built to Last
The need for new and improved transformers presents the opportunity to start with a clean slate; why build something that isn’t made to last? Current times call for durable, updated transformers, which is why it’s crucial to properly evaluate the design and specifications of each asset carefully.
But it’s just as important and efficient to optimize the health of the assets we have in the field today. Older transformers are starting to age and deteriorate, making them more susceptible to failure as well as severe weather and storm-related damage and the need for new units is more important than ever. With the increased availability of new materials, it’s crucial to ensure new transformers are being built for the long haul. Following IEEE standards, conducting formal design reviews and factory witness tests are important steps to ensure that the manufacturer is constructing the transformer for its intended application and technical specifications. Testing a transformer’s magnetic circuit, windings and insulation, impedance and loss, interoperability, thermal performance and short circuit resistance are particularly important for renewable transformers and those specific to microgrids where the harmonics impact may be more severe than typical T&D units.
No matter where a transformer is in its lifecycle, proactive maintenance and condition monitoring tools should also be implemented to optimize its health. The Calisto® platform provides a wide range of options for testing and analysis. With the Calisto T1, engineers have the ability to test the functionality of bushings to ensure they’re working efficiently to reduce noise and vibration, while providing insulation to high voltages passing through. The T1 also contains a partial discharge guard that helps eliminate PD, working to prevent the aging of insulating material and avoiding electrical breakdown. The careful preservation of materials is important when monitoring a transformer. Using a partial discharge detector, such as the T1, to maintain a transformer will make the power grid that much more resilient.
The brand-new Calisto R9 Dissolved Gas Analysis (DGA) monitor provides critical DGA readings of all key transformer fault gases with no consumable gases and self-calibrates with water for accurate readings for the long haul. Other tools, like the Calisto H1, continuously sample the oil in transformers to accurately detect high levels of hydrogen, which may be indicative of an electrical fault. Constant testing is key to avoiding a fault, which could lead to an entire grid outage. Grid outages can impact the service of natural gas, posing health and environmental concerns and setting off a dangerous chain reaction. Utilizing the right set of condition monitoring tools to construct transformers and using these tools regularly to monitor the new grids is important to transformer health and will help to maintain their resiliency over time.
Whether electricity is coming from the traditional power grid or a smaller microgrid, one thing is for certain: transformer breakdown and failure will occur if the units aren’t preserved properly. The availability of materials shored up by President Biden’s executive act will ensure new grids can be constructed. From that point, they’ll need to be properly maintained to extend the life of the transformer, and that’s where condition monitoring tools play a vital role. A healthy, functioning transformer is prepared for unexpected events and makes for a stronger, more resilient power grid.