Efficient and Low-Cost Operation & Maintenance Solution for Electronic Voltage Transformers (EVTs)
1. Current Challenges and Opportunities
Traditional electromagnetic voltage transformers (VTs) face issues such as accuracy susceptible to load variation, ferroresonance risks, high maintenance costs, and difficulty in timely detection of latent faults. EVTs, utilizing capacitive voltage division or optical principles combined with signal processing technology, provide the technical foundation to break through the bottlenecks of traditional O&M models.
2. Core Solutions for Efficient and Low-Cost O&M
- 2.1 Paradigm Shift: From "Time-Based Maintenance" to "Condition-Based Maintenance (CBM)"
- Technical Support: EVTs feature built-in self-diagnostic modules and comprehensive state parameters (e.g., environmental parameters, operating voltage/current, component temperatures, communication status), enabling "panoramic awareness".
- Intelligent Diagnostic Platform: Deploy edge gateways and cloud-based analytical platforms (AI-driven) to analyze state data in real-time, accurately identifying potential degradation trends (e.g., capacitor aging, abnormal power supply fluctuations).
- Condition-Driven Maintenance: Trigger maintenance work orders based on condition assessment results, completely replacing the inflexible "one-size-fits-all" periodic outage overhaul model.
- 2.2 Active Defense: Eliminating Latent Faults, Mitigating Major Risks
- Early Fault Warning: The system automatically identifies and alerts on early-stage risks like declining insulation performance, abnormal temperatures, or power supply anomalies, enabling intervention before equipment failure.
- Prevent Protection Misoperation/Refusal: High reliability ensures continuous and accurate voltage signals are provided to protection relays, avoiding protection system failures caused by VT faults and safeguarding grid stability.
- Eliminate Metering Disputes: Maintains excellent accuracy (better than ±0.2%) and long-term stability (<0.1%/year) across the full temperature range, reducing billing disputes arising from metering deviations.
- 2.3 Lean Management: Digitalization Empowers Spare Parts Inventory Optimization
- Predictive Stocking: Forecast the lifespan of critical components and spare parts demand based on equipment condition assessments and historical data analysis, enabling precise procurement planning.
- Intelligent Inventory Management: Establish digital ledgers for real-time visibility of spare parts status (in-use, in-stock, remaining life), reducing slow-moving inventory and unlocking tied-up capital.
- 2.4 Efficiency Leap: Smart O&M Tools Boost Efficiency and Reliability
- Mobile O&M: Use a mobile App to receive work orders, view real-time/historical status, access documentation, and guide maintenance operations.
- Full Lifecycle Asset Management: Build electronic equipment records integrating factory data, historical status reports, and maintenance logs, providing complete data support for decision-making.
- Enhanced System Reliability: The proactive maintenance strategy significantly reduces unplanned outages caused by sudden equipment failures, improving overall grid reliability.
3. Quantified Core Advantages
|
Effect |
Approach |
Outcome |
|
Reduced O&M Costs |
Replacing time-based with condition-based maintenance / Lower failure rates |
O&M costs reduced **≥ 40%**, significantly cutting labor, material, and outage loss costs |
|
Mitigated Safety Risks |
Real-time latent fault warnings / High-reliability assurance |
Elimination of protection misoperations/refusals or metering disputes caused by VT latent faults |
|
Optimized Spare Parts Mgt |
Predictive stocking / Intelligent inventory management |
Spare parts inventory turnover rate increased 30%+, slow-moving inventory reduced **≥ 50%** |
|
Improved Efficiency & Rel. |
Mobile O&M / Proactive maintenance strategy |
O&M efficiency improved 50%, system availability rate increased to **≥ 99.9%** |
4. Implementation Path Recommendations
- Pilot Projects First: Deploy EVTs and associated condition monitoring systems at critical sites or in new projects to validate the solution's effectiveness.
- Platform Integration: Seamlessly integrate EVT condition data into existing production management systems (MIS/PMS) or new smart platforms.
- Process Reengineering: Optimize equipment inspection, testing, maintenance standards/procedures, and work order dispatch processes based on CBM requirements.
- Personnel Enablement: Conduct new skill training programs focused on condition-based maintenance, cultivating multi-skilled O&M personnel with data analysis capabilities.
- Continuous Improvement: Regularly evaluate O&M effectiveness, iteratively refine analysis models and strategies, and continuously enhance lean management levels.
