Research On Partial Discharge Fault Inspection System Of Switchgear Room Based On UHF Detection Method

The switch cabinet is an important equipment for breaking,isolating and extinguishing arc in the power system,and its safety and stability is of great significance to the power grid.The main faults of switch cabinet include insulation discharge,misoperation and overheating.Partial discharge is not only an important cause of switch cabinet fault,but also a typical symptom.Therefore,multiple and accurate measurement of partial discharge signal of switch cabinet can judge the insulation condition of switch cabinet in advance and ensure the operation safety of switch cabinet.At present,the detection of partial discharge fault of switch cabinet is becoming more and more normalized.If it has been manual detection as the main way,it needs to invest a lot of manpower and resources,so the use of inspection robot is more and more.But at present,the detection content of inspection robot is mainly light,temperature,sound,gas and so on,and the detection of partial discharge is less.Based on UHF detection method,this paper designs a partial discharge fault inspection system for switchgear room.Firstly,this paper introduces the significance and background of the research on partial discharge inspection technology of switchgear,and analyzes the related work of inspection robot and partial discharge detection technology.Finally,it explains the research content and structure arrangement of this paper.Secondly,according to the theory of antenna receiving and the principle of log periodic antenna structure,the PD UHF sensor is designed.The simulation model is established,the relevant excitation and boundary conditions are set,and the log periodic antenna is optimized by analyzing the simulation results under different structural parameters.Thirdly,the on-board detection board of partial discharge is designed.Due to the high frequency of the signal collected by the sensor,it is difficult to sample directly.Using the detection unit to envelope the signal,the envelope signal with relatively mild change can be obtained,which can effectively reduce the sampling pressure.According to the parameters and frequency characteristics of each component,the filtering,amplification,acquisition and transmission links are designed.The UHF sensor is used to test the detection board to verify the feasibility of the detection scheme.Fourth,the partial discharge signal recognition method is studied.As the uploaded PD signals are too complex to be recognized directly,different types of PD data are very different on the whole.Therefore,the returned amplitude and phase signals are calculated and counted as three kinds of spectrums which reflect the distribution characteristics of the signal.The features are extracted from these three kinds of spectrums,and the recognition is carried out by BP neural network and BP neural network optimized by genetic algorithm.The recognition effect of the system is analyzed by specific data.Finally,the mapping and path planning of the inspection robot under the ROS system are studied,and the whole system is installed.TTL is used to transfer USB to make the ROS system communicate with the detection board,and control the opening of the detection board when reaching the detection location.Verify the effectiveness and stability of the navigation system in different environments,and verify the patrol performance of the system in the actual switch cabinet room.In conclusion,based on the partial discharge UHF detection technology,this paper designs the partial discharge inspection system for switchgear room,which provides a certain reference for the field of partial discharge inspection robot technology.