Intelligent Surge Arrester Monitoring: Trends, Challenges & Future Outlook

1. Current Status and Shortcomings of Online Monitors

Currently, online monitors are the most commonly used tools for surge arrester monitoring. While they can detect potential defects, they have significant limitations: manual on - site data recording is required, precluding real - time monitoring; and post - collection data analysis adds to operational complexity. IoT - based intelligent monitoring overcomes these issues—collected data is uploaded via the IoT to processing platforms, and combined with big data analysis, it identifies hidden dangers and provides early warnings, effectively reducing the difficulty of power operation and maintenance.

1.1 Defects of Current - stage Online Monitors

As a core monitoring method for surge arresters, online monitors expose multiple problems in application:

• Poor Environmental Adaptability: Most surge arresters are installed outdoors, and long - term exposure leaves monitors prone to dial aging and seal failure, causing device damage and failure to observe data.

• Mechanical Component Failures: Ammeters mostly use mechanical pointers—thermal deformation or mechanical jamming can cause needle sticking, misdisplaying leakage current. Action counters with mechanical structures also easily jam, affecting counting accuracy.

• Manual - Dependent Operation and Maintenance: On - site recording of discharge times and leakage current by operation and maintenance personnel is required; special scenarios (inaccessible areas) need telescopes or drones, reducing efficiency.

• Difficult Data Identification: Limited by monitor quality, operation and maintenance personnel struggle to effectively judge equipment status from displayed data.

2. Development Trends of Intelligent Monitoring for Surge Arresters

To address online monitor issues, leveraging the Internet of Things and intelligent manufacturing, intelligent monitoring will upgrade in three directions:

2.1 Transmission Method: Wired → Wireless

Current intelligent monitoring mostly relies on RS485 wired connections, suitable only for specific scenarios like substations. For lines and remote areas, transmission distance is a constraint. Wireless technologies such as LoRa, NB - IoT (Narrow - Band Internet of Things), and GPRS offer wide coverage and low power consumption. Especially LoRa and NB - IoT, as emerging IoT technologies, will see broader future applications.

2.2 Power Supply Method: Active → Passive

Currently, intelligent monitoring depends on external DC power. In the future, it will evolve toward passive power supply for green and low - consumption operation. Energy harvesting via surge arrester leakage current, solar panels, or built - in batteries is feasible—using leakage current for energy storage is most advantageous, avoiding issues like insufficient solar radiation and frequent battery replacement.

2.3 Installation Method: External → Internal

Current intelligent monitoring is mainly external—while not limited by size and easy to replace, it is vulnerable to environmental influences. Internal installation requires integration into the surge arrester cavity, demanding smaller sizes and facing technical barriers. However, it eliminates external environmental impacts, ensuring better long - term stability.

3. Expanded Monitoring Directions for Surge Arresters

Based on fault modes and mechanisms, intelligent monitoring units will focus on four dimensions:

3.1 Pressure Monitoring

For 35kV and above porcelain - housed surge arresters, helium mass spectrometry leak detection and high - purity nitrogen filling (micro - positive pressure technology) are used during manufacturing to prevent moisture intrusion and improve insulation. However, long - term operation causes seal aging, nitrogen leakage, and moisture ingress, potentially leading to explosions. Intelligent monitoring units monitor internal pressure in real - time; data upload and platform analysis enable early warnings for timely replacement and repair.

3.2 Temperature and Humidity Monitoring

For surge arresters with insulating tubes/porcelain housings and internal air, assembly requires strict temperature and humidity control. Intelligent units monitor internal conditions, upload data regularly, and trigger alarms when limits are exceeded, enabling proactive operation and maintenance.

3.3 Leakage Current and Resistive Current Monitoring

These currents are core indicators of surge arrester performance. Long - term operation, external environments, and insulator pollution cause resistor aging and seal failure, increasing currents. Monitoring current trends helps detect hidden dangers and prevent accidents.

3.4 Impulse Discharge Current Monitoring

Collecting discharge times, current magnitudes, and action times supports operation and maintenance planning and fault analysis.

4. Technical Breakthrough Directions for Intelligent Monitoring

External intelligent monitoring is emerging (unconstrained by space, highly compatible), but internal monitoring is in its infancy, facing three technical challenges:

4.1 Energy Harvesting Optimization

Internal monitoring relies on surge arrester leakage current for energy, but small currents hinder real - time transmission. Combining leakage current harvesting with built - in batteries shortens data transmission cycles, balancing energy supply and data transfer.

4.2 Signal Transmission Enhancement

Internal integration exposes monitors to signal attenuation/shielding from arresters and components; high - voltage electric fields also interfere. Signals must be optimized for better penetration and anti - electromagnetic interference.

4.3 Lifetime Verification and Reliability

Internal monitoring is hard to replace; surge arresters require 30 - year design lifetimes (over 20 years in practice). Monitoring unit lifetimes must match, and heat from arrester actions must not affect module reliability.

5. Current - stage Applications of Intelligent Monitoring

Intelligent monitoring remains in pilot stages, mainly applied in power and railway demonstration projects (e.g., the intelligent traction substation in Xiongan, 750kV Yan'an Smart Substation, and UHV DC converter stations). Pilots verify technical feasibility, with intelligent - monitored arresters meeting performance expectations.

6. Conclusion

Intelligent monitoring enables real - time online status tracking, improving risk identification accuracy and reducing operation and maintenance difficulty. Despite remaining technical challenges, aligned with intelligent, green, and environmentally friendly trends, it will gradually replace traditional online monitors. Widespread adoption in power and railway systems will strengthen grid safety and support sustainable energy development.