Efficient operations and maintenance (O&M) of equipment and systems is one of the top priorities of utilities globally. Keeping transmission assets in good health is essential for ensuring uninterrupted power supply and maintaining a congestion-free network. Moreover, proper asset management reduces outages and equipment downtime, and extends the usable life of assets. With the emergence of advanced technologies and digital solutions, utilities are increasingly upgrading their O&M practices and asset management strategies by deploying internet of things and data analytics, as well as various new-age monitoring solutions such as drones and high resolution cameras to monitor assets.
Asset life cycle management broadly involves three aspects. The first is the deployment of assets, which entails identification of the requirements of the utility, deciding on equipment specifications and design, and undertaking equipment procurement. The second is the O&M of assets, including installation, commissioning, operations and monitoring. The third is upgradation/replacement of assets, which involves maintaining, refurbishing, disposing of and replacing assets.
An asset is selected based on the requirements of the utility, keeping in mind its design specification. Post installation and commissioning, the asset initially runs at its highest efficiency, thus optimising costs. With constant O&M, it can achieve its highest total productivity, but in the process, it may sustain wear and tear and require refurbishment or even partial replacement. Over long periods of use, its marginal productivity will decline steadily, eventually leading to it being replaced or disposed of.
Asset management system and strategies
Digital transformation: Digitalisation is transforming asset management with the rise of IoT-based solutions. The digitisation of processes and systems begins with the integration of online sensors at the equipment level. It involves changing work processes through the use of digitised data and the adoption of solutions such as automatic fault analysis systems and predictive outage management systems, as well as the development of business dashboards. This facilitates complete digital transformation of a utility, giving it the capability to operate its assets entirely through IoT. There are numerous benefits of digital transformation. Digitalised controls and software-based asset management allow utilities to monitor assets from the remotest locations in real time. Coupled with the cloud, this helps utilities store large amounts of data for future reference and analytics. From inferential studies performed on data, utilities can devise strategies for preventive maintenance and create operation models that optimise performance.
The Power Grid Corporation of India (Powergrid) has developed the Powergrid Digital Application for Routine Patrolling and Assessment of Network (PG-DARPAN) – an in-house-developed model and application for transmission line patrolling activities. It helps improve real-time monitoring and patrolling efficiency, and assists in complete geographical asset mapping. It provides automated management information system and legacy reports along with a defect catalogue, as well as rectification record monitoring services.
Powergrid has also developed its own Powergrid Asset Life Management System (PALMS). PALMS is a web-based portal, developed in-house, for real-time health assessment of about 3,600 transformers/reactors. It categorises critical equipment based on operational experience and the latest international standards, and constantly performs risk-based severity indexing of transformers and reactors, and age assessment for integration. It also performs dynamic AMP scheduling based on severity. Further, Powergrid has created an asset management dashboard called UDAAN, which is a Qlik-based dashboard for monitoring the integration of data from various digital sources. It provides a geospatial view of assets, daily operational history and maloperation details. It also monitors key performance indicators and undertakes inventory and equipment health analysis. It provides outage management tools and weather forecast models. The transco has also developed portals such as the AI-based AMRIT for defect identification in transmission lines, and DISHA (Digital Self-Help Assistant), which is a natural language processing-based chatbot for addressing queries related to asset management.
Process re-engineering: With the data that is being gathered and processed through the digitisation of systems, utilities are undertaking data analytics and drawing inferences to change their processes and improve the design of their existing systems. Re-engineering of processes and systems such as patrolling, maintenance, warning systems and asset health monitoring is being undertaken to enhance the performance of utilities.
Powergrid has re-engineered its patrolling system with the deployment of an advanced technology solution. The transco is undertaking vulnerability-based patrolling by deploying high zoom cameras and switching to app-based ground patrolling. It is also undertaking drone-based aerial patrolling on a trial basis, and deploying AI- and machine learning-based solutions for defect identification.
In order to become self-reliant in the O&M of assets, Powergrid aims to resolve its O&M issues without assistance from original equipment manufacturers. The transco set up its first repair site for 765 kV reactors in 2020, at Aurangabad. It is also undertaking repairs of gas-insulated switchgear (GIS) modules at various substations, and has fabricated parts of thyristor-controlled series capacitor modules using 3D printing. Powergrid has formulated an effective strategy for protecting lines and assets from cyclones, which has helped the utility endure eight cyclones without much damage to its assets. To this end, the utility undertakes identification of critical transmission elements using satellite imagery, 24×7 control rooms for monitoring, and adequate resource planning. It also undertakes special patrolling and defect liquidation for critical elements.
Technology upgradation: Utilities are increasingly adopting state-of-the-art technology to enhance their operational performance and efficiency, and enhancing the sustainability of their operations.
Powergrid commissioned the world’s first 400 kV reactor with natural ester oil in August 2021 at the Maithon substation in West Bengal. Natural ester fluid is a vegetable seed-based fluid derived from renewable agricultural seed crops. The application of ester fluids at higher voltage levels provides utilities with a safe and green solution for high equipment performance. Besides, natural ester oil is biodegradable and has a minimal environmental footprint as well as higher fire resistance than mineral insulating oil. Powergrid also commissioned the world’s first 400 kV digital substation based on an IEC 61850 process bus at Malerkotla, Punjab, in December 2020 by retrofitting an old substation. Moreover, Powergrid has become the fourth utility in the world to establish a facility for alcohol-based testing of ageing markers (set up at Manesar in 2022). It offers several advantages, such as detecting early stage ageing of paper, easily differentiating between normal ageing and localised overheating, a higher recovery rate than furans after degassing of old units, and higher detectability at temperatures above 100 ºCelsius than furans.
The significant efforts undertaken by Powergrid to upgrade O&M and asset management strategies have increased its system efficiency to 99.83 per cent and reduced line tripping to an all-time low of 0.33 per cent, bringing it on par with international players. The failure rate of its transformers has decreased to 0.66 per cent, and the failure rate of GIS equipment and transmission has also declined drastically.
Going forward, in order to upgrade O&M and enhance asset management, Powergrid plans to use robots for substation inspection. The transco aims to deploy digital twins for vegetation management by creating digital twins of physical transmission line networks and mapping vegetation data (such as vegetation type and growth rate) to schedule patrolling and right-of-way management based on the anticipated rate of growth. Furthermore, the transco aims to transition to agile and paperless transmission asset maintenance through the use of augmented reality glasses to connect with remote experts and data systems, QR code-based equipment identification, digitisation of maintenance task lists, and auto-logging of records from the field to a central data repository.
To conclude, digitalisation and IoT-based interfaces have the potential to significantly revolutionise O&M and asset management for transcos. In order to realise the full benefits of digital solutions, it is essential to devise a roadmap for the digital transformation of utility operations. Implementing digital solutions in silos will fail to deliver the desired results. It is essential to ensure that digital solutions are interconnected, and that they operate in tandem. Apart from this, a crucial yet often missed step in building robust asset management systems is upgrading the most important intangible asset, namely, human capital. Capacity development through skill-building, that is, providing working knowledge and documented learning, can bring about a big change in the efficiency of daily operations, which will eventually improve all performance parameters.
Based on the presentation by Powergrid, at a recent Power Line conference