Robust power transmission is crucial for sustaining the growth of the power sector. Asset management strategies are imperative to ensure operational efficiency, reliability and the overall smooth functioning of the power system. In recent years, the sector has witnessed a surge in innovative solutions and technological advancements aimed at extending an asset’s useful life through condition assessment, refurbishment and maintenance management. Regular operations and maintenance (O&M), along with the upgradation and replacement of assets, also plays a key role in managing transmission assets.
A look at the key trends and best practices being adopted for asset management…
Reliability-centred maintenance
Reliability-centred maintenance (RCM) is a cornerstone of effective asset management and crucial for addressing network complexities, handling ageing infrastructure, and ensuring cost optimisation and reliability.
RCM tailors maintenance plans for each asset based on its criticality and significance to grid operations. It typically integrates the health model, degradation model and impact model to provide valuable insights. The health model computes the asset health index using current data on the asset, while the degradation model evaluates failure probabilities based on historical data on asset failures. The impact model further assesses the potential impact of failure on the grid, and combines this with failure probabilities to arrive at a risk index. This entire process enables real-time health indexing along with risk-impact mapping. As a result, it leads to numerous benefits, including extended equipment life, reduced preventive maintenance, lower maintenance costs, optimisation of inventory, improved resource planning and data-driven decision-making. Notably, RCM can facilitate a reduction in man-hour requirements, with transmission line patrolling decreasing by 23 per cent and substation maintenance by 35 per cent.
RCM is being rapidly transformed by advancements in technology, such as sensors and data analytics, along with rising stakeholder expectations for higher service levels and sustainability. Standardising resilience and business continuity plans can further enhance benefits. Leveraging digital tools and data analytics for disaster prevention, such as cyclone preparedness, can also enable more proactive responses to emergency situations.
Best practices
GPS-enabled apps and high-resolution ground cameras are extensively being utilised for the maintenance of transmission lines, along with aerial inspections using helicopters, drones and GIS mapping. Similarly, substation maintenance encompasses asset management practices ranging from condition monitoring to asset health indexing for transformers and reactors.
Hotline maintenance utilises insulated buckets to ensure the safety and uninterrupted upkeep of the transmission system, including repairing damaged equipment. This method provides numerous benefits, such as reducing technical losses, preventing costly outages, facilitating operation without disruption, and ensuring safety while performing critical maintenance tasks on live transmission lines. This is further complemented by the emergency restoration system, which is used for the quick, safe and efficient restoration of power during interruptions caused by natural disasters, sabotage
or vandalism.
Utilities are also investing in new technologies such as advanced tower designs, high-temperature low-sag conductors and transmission line arresters, enhancing system reliability. For substations, the adoption of resin-impregnated paper bushings in transformers provides improved insulation and reliability.
Notably, the implementation of ester-based transformer fluids offers superior fire safety characteristics and biodegradability compared to conventional mineral oil-based fluids. Being a vegetable seed-based fluid derived from agricultural seed crops, natural ester offers a safe and green solution for high equipment performance. Additionally, for early-stage detection of degradation in transformer insulation, innovations such as alcohol-based ageing markers provide many advantages. Compared to furans, these offer a higher recovery rate after degassing old units, as well as higher detectability at temperatures exceeding
100 °C. Further, internet of things-based automation of valve hall inspection using wireless thermovision scanning can be beneficial for safely monitoring critical equipment and high-risk assets.
Utility initiatives
As the world’s largest transmission utility to achieve the ISO 55001 certificate, on June 6, 2024, Power Grid Corporation of India Limited (Powergrid) is committed to the effective management of its transmission assets throughout their life cycle. Powergrid’s strategic asset management plan covers all aspects of Powergrid’s transmission asset management domain, including the technical management of assets such as towers, conductors, transformers, reactors and switchyard equipment. From digital transformation, re-engineering processes, technology upgradation and human capital deployment, Powergrid is adopting various initiatives to enhance asset overview, foster innovation, optimise business performance and enable smarter operations.
It has digitalised processes by converting all analogue processes into digital forms by utilising SAP technology for enterprise asset management and QR code-based data entry of test results.
Powergrid Digital Application for Routine Patrolling and Assessment of Network (PG-DARPAN) is being used for app-based defect detection in transmission lines. Further, it has established the National Transmission Asset Management Centre (NTAMC), which is a centralised facility for the remote operation and monitoring of all Powergrid substations, as well as for the centralised real-time monitoring of relays and optimisation of human resources by eliminating shift operations at substations. As of December 2024, around 281 substations were under remote operation from the NTAMC.
Powergrid is also leveraging digitalised tools to optimise work processes through technologies such as drone-based patrolling and predictive outage management. Additionally, its artificial intelligence-driven defect identification system, called Asset Management through Artificial Intelligence in Transmission (AMRIT), is an image-processing-based solution for identifying defects in transmission lines. The system can identify over 40 types of defects with a processing speed of 100 photographs per minute and an accuracy rate of more than 70 per cent. Further, real-time health assessment of assets using the Powergrid Asset Management System aids in risk-based severity indexing of transformers and reactors, and provides a dashboard for monitoring critical equipment.
Another asset management highlight is the use of dynamic line loading (DLL). DLL has the ability to adjust the capacity of an overhead line in real time, based on varying climatic conditions (temperature, radiation, wind speed and direction). DLL implementation is being carried out in the 400 kV D/C Madurai-Tuticorin line.
Another key initiative is the implementation of e-vegetation management across six transmission lines (high vegetation-prone) in the north-eastern region. This aims to assist inspection and maintenance teams in mapping transmission lines.
Apart from this, the Unified Digital Assessment of Asset Network platform integrates all digital data sources and asset registers. It offers various benefits, such as a geospatial view of assets and facilitates the monitoring of key performance indicators, critical asset identification, inventory analytics, equipment health analysis and outage management tools.
Meanwhile, 3D printing is being utilised for the manufacture and repair of key components, resulting in substantial cost savings. Powergrid has also successfully introduced the concept of digital workers through the incorporation of augmented reality-based digital headgear and tablet-based intelligent inspection to facilitate O&M. The headgear enables remote virtual supervision and assistance, thereby reducing chances of human error during maintenance tasks. Tablet-based intelligent inspection allows for end-to-end asset management with QR code-based asset tracking, ensuring the efficient, paperless execution of O&M tasks.
Powergrid is also engaged in various capacity-building initiatives through skill enhancement of its employees. Best practices are documented on its e-learning platform, PRAGYAN, and learnings are shared at various national and international forums.
Conclusion
The power transmission sector is undergoing a transformative shift, driven by a surge in innovative asset management solutions. By leveraging advanced technologies, the sector is enhancing operational efficiency, optimising operations, minimising equipment failure, and ensuring high system availability and reduced tripping. Collectively, this not only factors into a more reliable and efficient grid, but also paves the way for renewable energy integration, which is essential for meeting the ever-growing demand for energy.