The paper introduces the principle of on-line monitoring of the dielectric loss factor of capacitive equipment and the composition of the monitoring system. It explains the software-based mathematical analysis method and harmonic analysis method, and uses DSP for digital filtering. At the same time, the paper establishes an intelligent auxiliary monitoring terminal in the substation, uses the equipment ADP+ equipment protocol library to dynamically connect to various auxiliary monitoring equipment, uses signal frequency conversion sampling, alarm recording and other acquisition strategies to extract key equipment operation information, and hierarchically redundant storage data. Improve the real-time monitoring level of operating equipment and reduce the cost of operation and maintenance.

The insulator has an ice flashover failure. To reduce the calculation error of the equivalent icing thickness of transmission lines due to the insufficient number of sensors, a new online monitoring device for wire icing based on 3 sets of force sensors and inclination sensors was designed. The device integrates multiple monitoring functions such as micro-meteorology, wire temperature, distributed multi-rod tension, and images. The study found that the main reason for the ice flash of insulators is that the ice bridging the insulation on the string skirt. The high conductivity of melting ice water causes the ice flash voltage to be too low. A water curtain that blocks the melted ice water with high conductivity from forming a flashover channel. It is a basic measure to improve the ice-coated insulation and the flashover voltage of the ice string.

The gap between overhead ground wire insulators is changed by external force or subjected to overvoltage, intermittent breakdown will occur, and continuous arcing will occur in severe cases. Real-time monitoring of the current change on the ground wire is of significance to the reliable operation of the overhead ground wire major. The article proposes a method to detect the surface contamination of composite insulators by measuring the ground current of the insulator. The ground current characteristics of composite insulators are studied, and the test loops of composite insulator ground current, body leakage current and surface leakage current are established respectively. The above three currents of the insulator were measured and compared and analysed. At the same time, the article focuses on the design and development of the hardware system of the DC grounding system insulation resistance tester with digital display and multi-channel inspection function based on the microcontroller.

This article uses an image processing method to study the hydrophobicity of transformer composite insulators, and then determine the surface aging performance of transformer composite insulators. In order to meet the requirements of the randomness and ambiguity of the hydrophobic image, this paper uses a series of algorithms to process the hydrophobic image of the composite insulator: the enhancement of the hydrophobic image based on adaptive histogram equalization, the hydrophobic image based on wavelet transform Filtering and segmentation of the hydrophobic grade classification of composite insulators. Taking characteristic parameters such as the largest water droplet shape factor and area ratio as input, and the surface insulation aging performance of composite insulators as output, the relationship between insulation parameters and insulation aging performance is established. The simulation results show that the method can judge the surface insulation aging performance of composite insulators into three states: good, normal, and bad. Especially when the maximum water drop area ratio is input, the classification accuracy rate reaches 933%.

This paper introduces the items and principles of transmission line parameter test, finds out the interference factors through the detailed analysis of the field test results, and puts forward the relevant precautions.