Transformer Online Monitoring Systems: The Future Trend of Intelligent Operation for Oil-Immersed Transformers

1. What is a Transformer Online Monitoring System?

A transformer online monitoring system is an intelligent system based on sensor technology, data acquisition, and communication technology. It uses various sensors installed on the transformer body to continuously monitor its key operational parameters and transmits the data in real time to a backend monitoring center or cloud platform. Through intelligent analysis of this data, the system can assess the real-time condition of the transformer and issue timely warnings when abnormalities occur, enabling predictive maintenance.

2. Core Parameters of Transformer Online Monitoring

A comprehensive transformer online monitoring system typically tracks the following key parameters in real time:

1. Dissolved Gas Analysis (DGA) Online Monitoring: This is the most important and effective monitoring method. By analyzing the content and generation rate of key gases (e.g., H₂, CH₄, C₂H₂, C₂H₄, CO) dissolved in the transformer oil, it can accurately determine whether there are latent faults such as overheating or discharge inside the transformer.
2. Partial Discharge (PD) Online Monitoring: Monitors the intensity, frequency, and patterns of partial discharges within the transformer, effectively detecting early signs of insulation degradation.
3. Core Grounding Current Monitoring: Tracks the current in the core grounding circuit to determine whether a multi-point grounding fault has occurred.
4. Temperature and Load Comprehensive Monitoring: Monitors top-oil temperature, winding hotspot temperature, and load current in real time to assess the thermal aging and overload capacity of the transformer.
5. Micro-Water Content Monitoring: Tracks the moisture content in the transformer oil in real time to prevent a reduction in insulation strength due to dampness.

3. Core Value of Online Monitoring Systems

Deploying a transformer online monitoring system brings unprecedented changes to operation and maintenance:

• Enables Predictive Maintenance: Shifts from “time-based maintenance” to “condition-based maintenance,” allowing for planned repairs before failures occur and avoiding unexpected downtime.
• Enhances Safety and Reliability: Provides 24/7 uninterrupted monitoring, significantly reducing the risk of catastrophic failures.
• Optimizes Operational Costs: Reduces unnecessary scheduled downtime, extends maintenance intervals, and rationally allocates maintenance resources, lowering the total lifecycle cost.
• Supports Decision-Making and Management: Provides data support for equipment life assessment, spare parts management, and grid scheduling based on big data analytics.

4. How to Choose and Implement an Online Monitoring System

When selecting a transformer online monitoring system, consider the following factors:

• Monitoring Requirements: Choose the necessary combination of monitoring parameters based on the transformer’s voltage level, capacity, and criticality.
• Technical Maturity: Select sensors with high stability and strong anti-interference capabilities, as well as reliable communication solutions.
• Data Analysis Capabilities: The system’s backend software should have robust data storage, intelligent diagnostics, and clear alarm functions.
• System Integration and Scalability: The system should easily integrate into existing comprehensive automation systems or cloud platforms and support future functional expansions.

5. Conclusion: The Path Toward Intelligent Operation

Transformer online monitoring systems are no longer an optional configuration for large transformers but a standard for achieving digital and intelligent management of power assets. By enabling data-driven decision-making, they fundamentally transform transformer maintenance models, delivering significant safety and economic benefits.

For users seeking to enhance their operational standards and ensure the safety of critical power equipment, investing in a reliable transformer online monitoring system is undoubtedly a strategic choice for moving toward the future of intelligent operation and building a resilient power grid.