Improvement and Application of the Test Device for Surge Arrester Online Monitor

Edwiin

07/30/2025

1 Significance of Surge Arrester Online Monitors
1.1 Enhance Power System Safety, Reduce Lightning Damage

During lightning strikes, surge arresters play a core role in discharging overvoltage. Online monitors ensure arrester stability, detect potential faults in real - time, and trigger alarms for timely intervention—effectively reducing lightning - induced damage to power equipment and systems, and maintaining stable operation.

1.2 Real - Time Status Monitoring, Improve Maintenance Efficiency

Monitors track key parameters (e.g., leakage current) continuously. By identifying early faults and avoiding secondary accidents, they optimize maintenance scheduling, minimize unnecessary outages, and ensure reliable power supply—critical for system safety and efficiency.

2 Principles of Online Monitor Test Devices
2.1 Signal Acquisition

Monitors collect signals via arrester connections. Under normal operation, arresters remain stable; during overvoltage events (lightning/switching), they activate to discharge energy. Monitors use sensors to capture two key parameters:

Leakage Current: Current transformers convert leakage current into measurable electrical signals;
Operation Count: Discharge events are detected via specific signals generated during arrester activation.

2.2 Signal Processing & Analysis

Collected signals are processed through three key modules:

Amplifier: Boosts weak signals for subsequent processing;
Filter: Removes noise/interference, improving signal quality;
ADC (Analog - to - Digital Converter): Converts analog signals to digital format for precise analysis.

Processed digital signals are analyzed by microprocessors/chips, focusing on:

Insulation Assessment: Calculates leakage current magnitude/phase to evaluate insulation performance. Excessive leakage indicates degraded insulation and rising fault risks;
Operation Statistics: Tracks activation frequency, reflecting lightning activity levels or arrester degradation (over - frequent operations may signal intense lightning or performance decline).

3 Deficiencies of Traditional Test Devices
3.1 Low Testing Precision

Analog - based signal processing is vulnerable to interference (e.g., noise masking small leakage current changes). Sensor accuracy and signal conditioning circuits further impact precision, reducing data reliability.

3.2 Limited Functionality

Traditional devices only test basic parameters (leakage current, operation count) but lack advanced features (fault diagnosis, data analytics), making it hard to detect hidden risks comprehensively.

3.3 Complex Operations

Testing requires cumbersome wiring (e.g., sensor installation, signal connections) and unfriendly interfaces, increasing user error risks and operational difficulty.

3.4 Poor Reliability

Mechanical components (e.g., switches prone to wear, poor contact) and analog circuits (sensitive to temperature/humidity) cause frequent failures. Maintenance demands specialized skills, raising costs and complexity.

Traditional device structures and defects can be visualized in Figure 1.

4 Improvement Measures for Surge Arrester Online Monitor Test Devices
4.1 Adopt Digital Signal Processing Technology

Digital signal processing technology boasts advantages such as strong anti - interference capability, high precision, and good stability. Applying it to the surge arrester online monitor test device can effectively enhance test accuracy and stability. For example, digital filtering technology can accurately remove noise interference in signals, significantly optimizing signal quality; digital signal processing algorithms can precisely calculate key parameters like leakage current and operation times, further improving test precision.

4.2 Add Functional Modules

To meet users’ demands for advanced functions of surge arrester online monitor test devices, the improved device adds functional modules such as fault diagnosis and data analysis. By analyzing parameters like leakage current and operation times, potential fault hazards of surge arresters can be accurately identified; statistical analysis of historical data helps clearly grasp the operation trend of arresters, providing reliable basis for preventive maintenance.

4.3 Optimize the Operation Interface

To improve the convenience of operating the surge arrester online monitor test device, the operation interface is optimized. For instance, touch - screen technology is introduced, allowing users to complete operations and parameter settings directly via touch; a graphical interface enables users to intuitively understand test results and device status, enhancing the operation experience.

4.4 Enhance Reliability

4.4.1 Modular Design

Adopt a modular design approach, dividing the test device into multiple independent modules. Each module can work separately, greatly reducing maintenance and repair difficulties and improving the device’s maintainability.

4.4.2 High - Quality Components and Materials

Select high - quality components and materials to ensure the stability and reliability of the test device at the hardware level, reducing issues caused by hardware failures.

4.4.3 Strict Quality Control

Implement strict quality control and testing procedures to comprehensively inspect the performance and quality of the test device, ensuring it meets design and usage requirements and laying a solid foundation for stable device operation.

The schematic diagram of the improved surge arrester online monitor test device is shown in Figure 2.

5 Case Analysis
5.1 Case Introduction

A set of surge arresters in a substation was selected as the test object. The improved test device was used to conduct comprehensive tests, including measuring parameters such as leakage current, operation count, and resistive current, as well as verifying functions like fault diagnosis and data analysis.

5.2 Test Process and Results

5.2.1 Leakage Current Test

The improved device measured the arrester’s leakage current, which remained stable within the normal range with no significant deviation from historical data. This indicates good insulation performance, with no abnormal increase in leakage current.

5.2.2 Operation Count Test

By simulating arrester operations, the improved device accurately recorded operation counts, matching actual actions. This confirms the device’s capability to provide reliable data for operation and maintenance.

5.2.3 Resistive Current Test

Resistive current measurements (via the improved device) stayed within normal ranges, consistent with historical data. This reflects normal resistive components, with no signs of aging or damage.

5.2.4 Fault Diagnosis Verification

By simulating faults (e.g., sensor malfunctions, signal conditioning circuit issues), the improved device accurately detected fault points and provided clear alerts. This verifies the reliability of its fault diagnosis function for timely defect identification.

5.2.5 Data Analysis Verification

Analyzing historical arrester data, the improved device generated trend charts for parameters (leakage current, operation count) and detailed reports. This demonstrates robust data analysis capabilities, supporting scientific operation and maintenance decisions.

5.3 Result Analysis

The improved test device features high precision, comprehensive functions, user - friendly operation, and strong reliability—fully meeting testing requirements for surge arrester online monitors.

Its fault diagnosis and data analysis capabilities enable proactive identification of potential issues, enhancing equipment reliability and safety. Overall, the device improves testing efficiency and accuracy, safeguarding the stable operation of power systems.

6 Conclusion

As power systems evolve, demands for accuracy and reliability of surge arrester online monitors continue to rise. This paper introduces improvements to test devices—optimizing signal acquisition, processing, control, display, and power modules—to enhance stability and precision.

Field tests validate the device’s effectiveness, providing a reliable basis for quality inspection of online arrester monitors. Future efforts should focus on advancing power equipment detection technologies, continuously refining test devices to further ensure the safe and stable operation of power systems.

Topics

High Voltage Electrical Apparatus Arrester and Fuse Applications and Trends

Edwiin

Hello，I'm Wdwiin. A decade of hands-on experience in electrical engineering, specializing in high-voltage systems, smart grids, and renewable energy technologies. Passionate about technical exchange and knowledge sharing, committed to interpreting industry trends with professional insights to empower peers. Connection creates value—let’s explore the boundless possibilities of the electrical world together!