Research On Insulator Image Acquisition Terminal Based On Enhanced Algorithm

With the development of digital image processing technology and the continuous advancement of the construction of "strong and smart grid",the detection and fault diagnosis of transmission lines are moving towards intelligence.Among them,the image-based insulator detection system can realize the detection of insulator hydrophobicity,contamination,cracks,etc.,and provide a basis for the analysis of the operation status of transmission line insulators.The detection system is mainly composed of a front-end video monitoring device,a data communication network and a back-end monitoring center.The insulator works outdoors.Due to weather,light and other factors,the quality of the collected images is poor,which makes it difficult to achieve accurate results in the subsequent detection algorithm processing.The existing solution is to perform enhancement preprocessing on the mass of collected images in computer software.This process is time-consuming.Researchers reduce the enhancement time by studying enhancement algorithms.This method has limited effects and is difficult to meet the requirements of real-time processing.The existing solution is to perform enhancement preprocessing on the mass of collected images in computer software.This process is time-consuming.Researchers reduce the enhancement time by studying enhancement algorithms.This method has limited effects and is difficult to meet the requirements of real-time processing.This paper improves the front end of the detection system,designs an FPGA-based insulator image acquisition terminal,proposes an improved histogram equalization algorithm,uses hardware to achieve acceleration,completes real-time acquisition and enhancement processing,and improves system detection efficiency.First,the FPGA-based insulator image acquisition terminal system is researched and designed.The hardware includes four modules,image acquisition module,image display module,FPGA core module,and Gigabit Ethernet transmission module.The software part uses Quatus Ⅱ software to complete the design of image acquisition,display and sending modules,and each module is designed as Avalon_ST interface custom IP,and the SOPC system construction is completed by calling the IP in the Platform Designer.Secondly,in-depth research on enhancement algorithms,theoretical research on enhancement algorithms commonly used in computer software(Retinex algorithm and histogram equalization algorithm),and then perform enhancement algorithm simulation on insulator images collected outdoors,and use image enhancement effect evaluation indicators for images before and after enhancement.On this basis,an improved histogram equalization algorithm is proposed,the design of the enhanced algorithm IP is completed,and the IP is called in Platform Designer to complete the design of the entire SOPC system.Finally,the design is powered on and tested,the logic analyzer is used to collect and analyze the waveforms of each module,the collected waveforms are compared with Modelsim simulation,and the image evaluation indicators are used to objectively evaluate the quality of the enhanced image.Through the analysis of experimental data,it is shown that the insulator image collection terminal designed in this paper has a good enhancement effect on the collected images,and can communicate with the PC through Gigabit Ethernet.For a resolution of 640x480 and a frame rate of 30fps,the enhancement processing time per frame of the video data stream is about 3.074570ms,so this design is very helpful to improve the efficiency of the insulator detection system.