Research On On-line Monitoring Method And Technology For Strain Clamp Of High Voltage Transmission Line

The strain clamp is an important tool in high voltage transmission lines.The reliability of its work directly affects the safety of high-voltage transmission lines.Under the thermal stress generated by wind load and day and night temperature difference,the strain clamp is prone to fatigue damage,and severe fracture failure may occur,which may affect the safe operation of high-voltage transmission lines and cause large-scale power failures of transmission lines,causing major problems.Production economic losses.Therefore,real-time monitoring of the operating state of the high-voltage transmission line is necessary for the safe operation of the high-voltage transmission line strain clamp and even the transmission line.Since the strain clamp is working in a high voltage environment,manual maintenance is very inconvenient,and it is impossible to grasp the running state of the clamp in real time,and it is impossible to accurately and accurately judge whether the clamp is abnormal.Therefore,the online monitoring system for the strain clamp of the transmission line is developed,the data of the clamp is monitored in real time,the operation status is evaluated,the early warning is given for various abnormalities,and the maintenance and repair are timely,so that the failure of the transmission line is of practical significance.The content of this paper is to design and develop the on-line clamp online monitoring system,using image processing means and multi-sensor data fusion algorithm to evaluate the working condition of the strain clamp,and provide the basis for the maintenance of the clamp.The details are as follows:1.According to the crack of the clamp,the type of monitoring signal(stress,temperature,image)and the position of the sensor are selected.The design and development of the hardware system of the monitoring system consisting of the front-end acquisition system and the back-end server.The front-end acquisition system is installed on the transmission line,realizing real-time communication in different places through the 4G network and the monitoring indoor back-end server.2.Developed embedded software for front-end acquisition system and background server software based on C# language.In the front-end acquisition system software,the AD7606 sample data is read by the analog SPI protocol.The timing restart and automatic calibration function are developed based on RTC,and the communication command is designed.In the background server software,the database and display interface are designed,and the producer consumer mode is used to solve the problem that the data receiving and processing tasks are inconsistent with the database storage tasks and the interface display task rhythm.3.The method of strain clamp?s crack identification based on image processing is studied.The adaptive homomorphic filtering method is used to solve the interference of different illumination conditions on the image signal,and the target region is effectively extracted by combining edge extraction,morphological operation and retaining the maximum connected domain.Through a large number of statistically extracted target area aspect ratios and circularities,the crack determination criteria were determined and experimentally verified.4.Apply the D-S evidence theory to the strain clamp state assessment.The Dickson criterion is used to eliminate the coarse errors in the stress and temperature data.The evidence is collected by hierarchical clustering method,and the proposition space is divided according to the actual situation of the line.The weighted similarity method is used to assign probabilities to different propositions.The result of the clamp state evaluation is given by using the evidence combination rule and the final decision rule.Finally,the fusion algorithm is verified simply.5.The monitoring system was assembled and tested in the laboratory,and installed in the monitoring site.The test results were good.