Agentic AI is the Future of Condition-Based Maintenance for Power Transformers

June 25, 2025
By Marc Antoine
19 min read

The traditional approach of time-based maintenance for high-voltage power transformers is giving way to condition-based maintenance (CBM) strategies enabled by Agentic AI

The Future of Condition-Based Maintenance for Power Transformers with Agentic AI

The traditional approach of time-based maintenance for high-voltage power transformers is giving way to condition-based maintenance (CBM) strategies enabled by advanced digital technologies.

In CBM, transformer health is monitored continuously through sensors and diagnostics, so that maintenance is performed as needed rather than on a fixed schedule.

This proactive method can catch developing faults (like insulation breakdown or mechanical wear) long before catastrophic failures. Modern CBM relies on data from diverse sources – dissolved gas analysis (DGA) of insulating oil, partial discharge (PD) detection, temperature and vibration sensors, moisture and dissolved solid measurements, etc. – to assess transformer condition. Importantly, these multiple diagnostics must be fused intelligently: each technique alone provides only a partial view.

Experts agree that combining online sensor data, offline tests, and expert assessments is necessary to form a reliable health index for a transformer.

Figure: Conceptual workflow of condition-based monitoring (CBM) for power transformers (adapted). Sensor data (online measurements), offline tests, and expert inputs are fused to compute a health state metric. The diagram illustrates how data acquisition and transformation feed into an aggregated condition assessment.

This fusion yields a single transformer health index – a quantitative measure of overall condition that utilities can track across their fleet. Leading standards bodies like CIGRE and IEEE endorse such health-index approaches. For example, CIGRE Working Group A2.49 advocates for health- and risk-based maintenance strategies that transition from calendar-based to condition-based decisions. In practice, utilities use algorithms (sometimes AI-based) to assign scores to each type of condition data and sum them into an index. This index identifies “bad actor” transformers – units with high failure risk – so resources can be focused where they yield the most reliability benefit.

Condition-based programs have shown real benefits. Studies and field experience demonstrate CBM can reduce unplanned outages and extend transformer life by detecting faults early. For example, a North American utility found that most transformer outages were triggered by specific component failures (bushings, tap changers, cooling system issues) that are detectable via targeted monitoring. By tracking those indicators, the utility gained advanced warning of problems and avoided several failures. CBM also cuts costs: maintenance is done only when needed, avoiding unnecessary overhauls of healthy units. In short, condition-based strategies optimize transformer life-cycle cost and grid reliability simultaneously.

From Time-Based to Condition-Based Maintenance

Traditional maintenance for large power transformers has been time-driven: routine overhauls or oil changes are scheduled at fixed intervals (for example, every 5 or 10 years) regardless of actual condition. While this approach addresses age-related wear, it often misses sudden faults that occur in between intervals. Statistics show many transformers fail unpredictably due to latent defects or unforeseen stresses. Conversely, uniform time-based work can lead to unnecessary downtime on healthy units. Today’s advanced CBM flip this paradigm. Instead of relying on elapsed time, CBM uses real-time condition data (oil tests, sensor readings) to decide when and what maintenance is needed.

Key CBM techniques include Dissolved Gas Analysis (DGA), often called the “blood test” for transformers, which measures gases (like hydrogen, methane, ethylene, etc.) dissolved in insulating oil. Elevated levels or changing trends in these gases indicate internal thermal or electrical faults. Partial Discharge (PD) monitoring detects localized arcing inside the winding or insulation – a critical early warning of insulation breakdown. Other tools include frequency response analysis (FRA) for mechanical deformation, dielectric tests, and moisture-in-oil tests for insulation health. Modern CBM systems also track transformer loading, temperature, and even environmental factors. All this data is aggregated to maintain an up-to-date health profile for each transformer.

Implementing CBM requires sensors and data infrastructure. For instance, many utilities now install online DGA monitors on transmission transformers, sending continuous oil gas readings to control rooms. The Dominion Energy case study shows how moving from manual to online DGA yielded faster fault detection with comparable accuracy. Similarly, online PD monitors and fiber-optic temperature gauges are increasingly common.

The core benefit is reliability: by catching anomalies early, CBM helps prevent failures. Industry reports note that utilities with comprehensive monitoring have substantially lower failure rates. A recent power industry whitepaper explains that CBM allows servicing transformers “as-needed” to prevent failures, and utilities moving towards CBM/predictive programs see fewer forced outages. In fact, one CIGRE survey found utilities embracing condition-based or predictive maintenance (using online monitoring) achieved significant reductions in major transformer events.

The Role of AI and Agentic Agents

Advanced analytics, especially artificial intelligence (AI), are taking CBM to the next level. Basic machine-learning models have long been used to detect anomalies in sensor data (e.g. unusual DGA trends). Today, generative AI (like GPT-style models) is being applied to digest maintenance logs, manuals, and past data to suggest diagnoses or work plans. The new frontier, however, is agentic AI – autonomous AI agents that can manage maintenance workflows with minimal human prompting.

Agentic AI refers to AI systems that operate as independent “agents” within defined boundaries. They continuously analyze streaming data and orchestrate maintenance tasks automatically. For example, an agentic AI platform connected to a transformer’s SCADA and Asset Management system could detect a rising DGA hydrogen level, cross-reference historical failures, and automatically generate a maintenance work order in the CMMS – even ordering needed parts through ERP integration – all before a human engineer is alerted. Unlike simple alerts, agentic AI can decide and act on maintenance needs within safe limits, essentially performing predictive and prescriptive maintenance at grid scale.

The architecture for agentic AI in maintenance typically has layers: data acquisition (gathering SCADA, sensor, GIS, and manual data), knowledge processing (applying domain logic and standards), decision intelligence (recommendation engine for actions), and action execution (automating CMMS updates and orders). Throughout, human oversight ensures safety – the AI agent suggests or takes actions only under operator authorization, and all actions are logged.

By using agentic AI, utilities aim to move from reactive maintenance to autonomous proactive maintenance. Instead of waiting for alarms or planning tasks, the AI continuously optimizes schedules and interventions. In reliability terms, one AWS presentation notes that agentic AI “transforms maintenance practices by enabling autonomous, data-driven decision-making at scale” – the system not only predicts failures but also executes corrective actions in real time. The US and European grid is already seeing early versions: for example, IBM’s CBM project with a Swedish brewery showed that coupling AI with CBM unlocked much more efficient maintenance. While that example was manufacturing, similar approaches are being piloted in utilities, as evidenced by emerging industry reports.

Agentic AI also interacts with Asset Performance Management (APM) software. APM platforms (like IBM Maximo, SAP EAM, ABB Asset Suite, etc.) are what utilities use to track asset data and work orders. An agentic CBM system connects to the APM database, feeding it real-time health analytics and automatically updating maintenance plans. This integration ensures that the APM always has the latest condition data for decision support.

Asset Performance Management Software and Data Integration

Asset Performance Management (APM) software is the backbone of modern transformer maintenance programs. APM systems aggregate data (sensor readings, test results, nameplate specifications, and maintenance history) and provide analytics dashboards for asset health. They can incorporate condition-based rules and health indices, thus linking CBM data to maintenance workflows. For instance, when an APM identifies a transformer’s health index dropping below a threshold, it can trigger a work order for inspection or repair.

In practice, utilities often start with enterprise CMMS/EAM (Computerized Maintenance Management System / Enterprise Asset Management) such as IBM Maximo or SAP PM. These systems schedule routine tasks and record events. An APM strategy enhances that by layering in advanced analytics. For example, DNV explains that modern APM “uses timely and relevant data about equipment health and performance” so utilities make “well-informed decisions” and realize measurable savings. Part of this is shifting from calendar-based to condition-based scheduling: one whitepaper notes that utilities improve APM by developing health-index ratings and prioritizing “bad actors” for maintenance.

Software solutions are available specifically for transformer CBM. Big vendors (GE Vernova, Hitachi ABB, Schneider Electric) offer APM or asset analytics suites tailored for power grids, often including modules for transformer condition monitoring. For example, Hitachi Energy’s APM Edge combines transformer expertise with analytics to deliver predictive insights. Similarly, GE’s APM software offers dashboards for equipment health and risk metrics. These platforms typically pull data from SCADA/RTU (remote terminal units), GIS (geographic info), and DGA/PD sensors. An agentic AI solution, by integration, would sit on top of these systems, using their data feeds and taking actions within the APM.

A key challenge is data standards and interoperability. Transformer data comes in varied formats (IEC 61850 from protection relays, proprietary DGA formats, IEC 60870/104 SCADA protocols, etc.). Utilities and vendors rely on standards like IEC 60076 series for transformer characteristics, IEC 61850 for substation communication, IEEE 802.15.4/ISA100 for wireless sensors, and IEC 62443 for cybersecurity. A modern CBM platform must map all this: for instance, IEC 60076-3 and C57.12 standards define the nameplate data fields (rated power, tap range, cooling class) which are useful baseline inputs for analytics. While specific nameplate data (transformer model, rating, impedance, winding ratios) typically come from manufacturer manuals (Siemens, Hitachi, GE), the critical parameters are captured in the enterprise asset database. These parameters set the expected operating limits (e.g., maximum temperature) that APM algorithms use to normalize sensor readings.

Similarly, oil test data must be integrated. IEEE Std C57.104-2019 (“Guide for the Interpretation of Gases Generated in Oil-Immersed Transformers”) and IEC 60599 provide interpretation tables and alarm levels for DGA. A CBM system uses these as rules: for example, IEEE defines multiple methods (e.g. Key Gas, Doernenburg, IEC ratio methods) and threshold levels. Software can automatically apply these rules to real-time DGA results. Transformer manuals from OEMs often recommend specific test procedures (like sampling intervals and acceptance limits for dielectric strength or moisture content), and a digital maintenance system encodes these schedules. By centralizing this information, APM software ensures that no test result is overlooked, and that AI models have access to the full context (age, design, past faults).

Global Case Studies and Deployment

North America (USA & Canada): Several utilities have adopted CBM with AI analytics. For example, Dominion Energy (US) implemented an online DGA monitoring system to evaluate transformer health daily. Engineers there found that continuous DGA matched lab results with less human effort, enabling faster decisions. In another case, large generators in the U.S. collaborate with research groups (EPRI, IEEE task forces) on “Asset Health Indices” combining offline tests (e.g. power factor, dissipation factor, oil furan) with online data. Many North American grid operators are now discussing “digital twins” for transformers, using machine learning to predict aging. Although fully autonomous agentic AI is not yet widespread, pilots are emerging – often with vendor partnerships (Siemens, ABB, Schneider) or startups like PowerGrids AI (see sidebar above).

Europe: European grid operators similarly emphasize CBM. The Doble case study from a European Independent Power Producer (IPP) illustrates a best practice: the IPP installed advanced online monitors (PD sensors, DGA, moisture) after experiencing failures. Integrating these with an asset risk management system enabled them to correlate PD events with tap-changer activity and generator operations, scheduling interventions before full failures. Scandinavian utilities, in particular, are leaders in substation digitalization and have trialed AI-based condition assessment. EU initiatives (like CENELEC standards revision and CIGRE Task Forces) encourage implementing IEC 60076 diagnostics and sharing data across utilities. European Renewable mandates (like the EU’s 2030 climate goals) also push networks to minimize outages, indirectly driving CBM adoption.

Asia-Pacific: In countries like China, India, and Japan, rapidly expanding grids and aging equipment have spurred analytics. Several Chinese utilities are developing AI models for transformer asset health, often within broader “smart grid” or “smart substation” programs. Academic institutions (Tsinghua University, IITs) publish research on ML for DGA and PD diagnosis. In India, the Central Electricity Authority and regulators encourage utilities to adopt APM tools (some Tata Power substations now use real-time monitoring with AI analytics). Japan’s TSO (TEPCO) has also piloted digital twins for large transformers. Government initiatives for grid modernization (due to high renewable penetration) are aligning with transformer CBM research.

GCC and Middle East: The Gulf region is in earlier stages, but signs of interest are growing. Countries like UAE and Saudi Arabia are heavily investing in grid resilience and smart infrastructure as part of national decarbonization goals. Some utilities (e.g. Abu Dhabi’s ADNOC, Dubai’s DEWA) have begun deploying smart sensors on critical equipment, including transformers, and partnering with tech providers for analytics. For instance, regional power companies are exploring IoT and AI platforms for predictive maintenance under initiatives such as “Masdar City Smart Grid.” Specific published case studies are scarce, but consulting firms report pilot projects using DGA and thermal monitoring on Gulf grid transformers. Given the harsh environment (dust, heat), condition monitoring can be especially valuable. Regulatory frameworks in the Middle East (like Saudi’s Vision 2030 or UAE’s National Energy Strategy) emphasize reliability and low losses, which CBM directly supports.

Cost-Benefit Analyses: The economics of CBM with agentic AI is compelling when scaled. Traditional maintenance often causes unplanned outages costing millions per event. For example, a single 500 MVA transformer failure can entail $10–30 million in downtime and replacement. Studies estimate that even preventing one catastrophic failure per year can justify the cost of monitoring hundreds of transformers. An internal analysis by a U.S. utility found that adding online monitors and analytics led to a ~20% reduction in maintenance costs over five years, mainly by avoiding wasted routine servicing. Sophisticated AI agents also boost efficiency: one pilot calculated that automating work-order generation through AI saved an engineering team about 30% of their time on diagnostics and scheduling. Meanwhile, some vendors claim ROI within 1–2 years due to extended transformer life and deferred capital replacements.

Deployment costs include sensors ($5k–$20k per transformer for DGA/PD monitors), software licensing, and integration. Many utilities offset this by phased rollouts on highest-risk assets. Complexity of integration (especially with legacy SCADA or old transformers lacking connectivity) remains a barrier. However, recent advances in wireless sensors (Zigbee, LoRaWAN) and inexpensive data loggers have made retrofitting older units feasible. Cloud-based analytics platforms also reduce upfront IT costs, enabling even smaller utilities to trial CBM and AI.

Technical Performance and AI Advances

Agentic AI systems enhance technical performance of CBM by constantly learning and optimizing. ML models can detect subtle patterns: for instance, a neural network may recognize that a slight increase in acetylene gas together with small vibration change predicts impending bushing failure, even if individual alarms aren’t triggered. Research on ML for transformers shows promising accuracy: one study using support-vector machines on SFRA and DGA data achieved over 90% correct fault identification. AI also helps interpret complex inputs like FRA or PD spectra faster than human experts.

Furthermore, AI can run “what-if” simulations. For example, a generative model might simulate aging scenarios (overloads, harmonic currents, ambient variations) on a digital twin of the transformer. The agentic system uses these simulations to refine maintenance schedules. Such predictive simulation is valuable under new grid conditions: IEEE Spectrum reported a system called “DigiGrid” that used machine learning on GIS and sensor data to predict switchgear failures; principles like this apply equally to transformers. The power of agentic AI is in tying together diverse data: it can learn the correlation between a transformer's load profile, ambient humidity, and oil aging rate, improving life-expectancy forecasts.

Another key metric is reliability improvement: utilities track metrics like Mean Time Between Failures (MTBF) and outage frequency. While long-term studies are still forthcoming, early adopters report significant gains. For instance, after deploying an AI-enhanced CBM program, one North American transmission provider saw a >50% reduction in load-loss due to transformer faults over 3 years (internal company report). Independent research on asset health indices also supports that maintaining assets by condition statistically reduces failure rates.

Finally, we note ease of deployment: modern platforms aim for plug-and-play. Many companies now offer transformer monitoring kits with preconfigured analytics. These can integrate with standard APM software or even cloud dashboards. Agentic AI modules can be added as a service layer on top of existing CBM setups. Open standards like IEC 61360 for asset description and ISO 55000 (asset management) frameworks ensure that new systems can join the enterprise ecosystem. In short, while big data and AI introduce complexity, tools are emerging to simplify implementation (many vendors now tout “AI-as-a-Service” for utilities).

Policy, Reliability Mandates, and Economic Impact

Current global trends make improved transformer maintenance a high priority. Reliability mandates from regulators (such as NERC in North America or EU Grid Codes) increasingly demand quantifiable asset performance. For example, North America’s latest Long-Term Reliability Assessment highlights the need for enhanced grid resilience as more renewables connect. Although transformers are not specifically singled out, the implication is clear: grid operators must ensure critical assets do not become single points of failure. In this environment, utilities justify CBM as part of compliance – demonstrating to regulators and stakeholders that they are actively managing asset risk.

Carbon and decarbonization goals indirectly support CBM. More reliable and efficient transformers reduce energy losses (since aging transformers waste more energy) and enable integration of renewables. For instance, IEEE PES is preparing a guide on transformer carbon footprint, linking proper asset life management to CO₂ reductions. The smarter an asset is managed, the less frequently it needs replacement (manufacturing new transformers has a carbon cost). Moreover, as grids incorporate more distributed renewables, large transformers will see varied loading patterns; maintaining them in top condition avoids unplanned outages that might otherwise force use of fossil backups.

Economically, investing in CBM with AI can be justified by avoided costs and optimized asset replacement. Financial models show that extending an asset’s service life by even a few years (via better health monitoring) yields large net savings, considering the capital cost of a new 500 kV transformer (tens of millions USD). Some regulators now allow utilities to recover investments in smart grid technologies through rate adjustments, recognizing that improved reliability is a public benefit. As one IEEE Spectrum analysis noted, operators show a willingness to pay for components that report their real condition. This willingness is likely to grow as decarbonized grids and electrification make outages ever more costly to society.

FAQs: Agentic AI and Transformer CBM

  • What is Agentic AI and how does it differ from traditional AI?
    Agentic AI refers to AI “agents” that autonomously perform complex tasks within defined rules, rather than just generating insights on request. In transformer maintenance, an agentic system continuously monitors data, makes decisions (like scheduling inspections or ordering parts), and can even execute actions in connected systems (CMMS, ERP) with human oversight. Unlike standard predictive models, agentic AI does not wait for a user to query; it actively manages the workflow.

  • Why are multiple monitoring techniques needed for a single transformer?
    Power transformers are complex machines. Oil tests (DGA, moisture, interfacial tension) detect internal aging and faults. Partial discharge sensors detect insulation breakdown. Frequency domain tests find mechanical shifts. Each test covers different failure modes. No single method detects all issues, so experts recommend fusing all available evidence. An integrated health index synthesizes these measures for a complete picture.

  • How does APM software support CBM?
    Asset Performance Management systems collect and analyze all equipment data in one place. They can automatically flag when a transformer’s health metric crosses a threshold and generate maintenance plans. Essentially, APM ties the technical condition data to business processes (budgets, crew schedules), ensuring maintenance is prioritized rationally. For example, DNV notes that APM platforms help “make well-informed decisions, realizing measurable savings” by using data-driven insights.

  • Are there real-world examples of AI improving transformer maintenance?
    Yes. Industry deployments – even if not always publicized – include utilities using ML for fault prediction. The IEEE Spectrum article on predictive maintenance showed a prototype (“DigiGrid”) that predicted switchgear failures from sensor and GIS data. While focused on switchgear, the concept applies to transformers: researchers estimate operators value assets that report their condition, a fundamental enabler for AI-based maintenance. Also, vendors and startups (as in the case of the Swedish brewery) have demonstrated reducing maintenance lead times with AI diagnosis. These point to tangible improvements even before full agentic autonomy is realized.

  • What are the main challenges in adopting agentic AI for transformers?
    Data integration is a big hurdle: many older transformers lack sensors or digital connections, and utilities must manage data silos. Cybersecurity is also critical when AI agents act on core systems. Standardization is ongoing (IEC 61850, etc.) to ease integration. There are also organizational hurdles: engineers must trust AI recommendations, which requires careful validation and explainability. Finally, capital cost and workforce training can slow adoption, though pilots suggest rapid ROI when significant failure risks are reduced.

  • How do standards support this evolution?
    Standards like IEEE C57.104 (oil testing), IEC 60076 series (transformer design and testing), and CIGRE guides define the diagnostic tests and criteria. Emerging standards may cover data sharing and AI ethics. Notably, IEC 60076 parts and IEEE guides provide the underlying “language” (e.g. DGA gas definitions, dielectric limits) that AI systems use. Frameworks like ISO 55000 (asset management) also support shifting to condition-based practices. As agents mature, we expect formal guidelines on AI in asset management (similar to ISO/IEC 42001 on AI management) to arise.

  • What is the economic impact forecast?
    Analysts predict substantial savings. McKinsey (for example) estimates that digitalizing maintenance can reduce overall maintenance costs by 10–20% across industries, which for utilities means tens of millions of dollars annually. Given transformers’ high replacement costs, even small reliability gains yield big benefits. Moreover, avoiding a single major substation outage can save upwards of $50M (avoided customer interruption costs, regulatory fines, etc.). On a global scale, smart maintenance could save utilities billions by deferring capital replacements and reducing losses. These economic drivers, coupled with regulatory incentives for grid resilience and efficiency, make investment in agentic AI-driven CBM increasingly compelling.

In summary, the convergence of advanced monitoring, AI analytics, and asset management software is reshaping transformer maintenance. By moving from calendar-based schedules to intelligent, agent-driven CBM, utilities around the world can achieve higher reliability, longer asset life, and lower costs. Case studies from North America to Europe demonstrate the technical viability, while emerging policies on reliability and carbon reduction provide further impetus. As one industry executive put it, integrating intelligent AI agents into transformer asset management is becoming “critical for modern grids” – and the results promise a more resilient, efficient electric infrastructure.

References: Key concepts and findings are supported by industry and academic sources (see footnotes). Detailed case studies and standards (IEC 60076, IEEE C57, CIGRE technical brochures) underpin these insights.

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