With the rapid development of the power industry, the safe operation of power transmission and transformation stations is increasingly valued. Partial discharge, as a key factor affecting the insulation performance of power equipment, has become an important means of ensuring the stable operation of the power grid through online monitoring technology. This article will provide a detailed introduction to the online monitoring technology of partial discharge in the Internet of Things protocol for power transmission and transformation stations, including its monitoring significance, system overview, design basis, functional characteristics, working environment, and monitoring parameters.

1、 Monitoring significance

As a core equipment in the power system, the operation status of transformers directly affects the safety and stability of the entire power grid. In the past, transformers were often regarded as equipment that did not require frequent maintenance or had longer maintenance cycles. However, recently40 years of operational experience have shown that insulation faults are always one of the important factors threatening the reliability of transformers. Especially at high voltage levels, the insulation failure rate shows a gradually increasing trend. Therefore, it is of great significance to accurately detect and judge the internal defect status of transformers before they fail, and make advance predictions to ensure the safe operation of the power grid.

Through the transformer partial discharge online monitoring system, the operating status of the transformer can be understood and grasped in real time, and the performance, service life, and utilization level of the equipment can be evaluated. This not only helps to arrange maintenance strategies reasonably and reduce the workload of on-site inspectors, but also effectively reduces the maintenance cost of transformers. At the same time, the application of this technology can also enhance the refinement level of production management and further improve the efficiency of production operation and maintenance.

2、 System Overview

The IoT protocol partial discharge online monitoring device for power transmission and transformation stations is a new generation of high-performance digital partial discharge online monitoring device that combines years of on-site processing experience in partial discharge measurement, using sensor technology, signal processors, computers, and other technical means and algorithms. The system adopts partial discharge sensors and partial discharge monitoring instruments, which have been tested for a long time in multiple substations and power plants, demonstrating excellent performancelHigh reliability and stability. Some products even discovered discharge faults in the monitored equipment on site, successfully avoiding major accidents.

3、 Design Basis

The design of this system strictly follows a series of national and industry standards, including but not limited to:

·Common technical requirements for high voltage switchgear and control equipment standards DL/T 593

·3.6kV~40.5kV AC metal enclosed switchgear and control equipment DL/T 404, GB 3906

·Partial discharge measurementGB/T 7354

·Guidelines for on-site measurement of partial discharge in power equipment DL/T 417

·Related standards for high voltage testing technology GB/T 16927 series

These standards provide clear technical guidance and requirements for the design, manufacturing, and testing of systems.

4、 Functional Features

The IoT protocol partial discharge online monitoring device for power transmission and transformation stations has various significant functional characteristics:

1. Strong anti-interference ability and accurate monitoring data: The partial discharge monitor adopts a fully sealed multi cavity shielding design, which has strong electromagnetic compatibility and anti-interference ability. At the same time, it is equipped with an analog-to-digital hybrid filtering function, which can achieve online monitoring of partial discharge in strong interference environments.

2. Provide multiple alarm methods: When the authorities exceed the standard, the monitoring device can actively send an alarm signal to the higher-level management equipment through the network and display the alarm information on the monitor.

3. Convenient equipment management: Several monitoring devices within the station can operate independently and record data separately. Meanwhile, multiple devices can also be managed uniformly by a single computer through a data communication bus.

4. Large storage capacity, convenient data backup: data retention period not less thanIn the case of 10 minutes, the data can be continuously saved for no less than 3 months. And data can be uploaded and backed up anytime through the network.

5. Rich data analysis and calculation functions: includingAnalysis and calculation of partial discharge parameters such as MAX discharge capacity, current discharge capacity, and discharge frequency.

6. Graphic interface: It has functions such as trend charts, real-time waveform charts, historical record queries, historical trend chart queries, and alarm record queries for various partial discharge signals.

5、 Working environment and monitoring parameters

This system is suitable for various working environments, and the power supply isAC 85-260V、50Hz/60Hz， The power consumption is 20W. In terms of monitoring parameters, the system has high detection sensitivity and a wide measurement range (10pC~100nC). At the same time, the setting of ultra-high frequency channel and high-frequency channel enables the system to capture partial discharge signals in different frequency ranges. In addition, the system also has multiple independent measurement channels, high sampling accuracy, and sampling rate, ensuring the accuracy and reliability of monitoring data.

In summary, the Internet of Things protocol partial discharge online monitoring technology for power transmission and transformation stations, as an advanced means of monitoring power equipment, plays an important role in ensuring the safe operation of the power grid. Through the application of this system, real-time monitoring and early warning of key equipment such as transformers can be achieved, providing strong support for the stable operation of the power system.