Research On Optimal Sensor Placement Method For 500KV Transmission Tower Condition Monitoring

Transmission towers are prone to collapse accidents under extreme weather or fatigue damage,and it is difficult to conduct manual inspection and maintenance.It is necessary to arrange sensors for state monitoring of transmission towers.However,the structure of transmission towers is complex,there are many nodes and the price of sensors is expensive,so it is impractical to install sensors on all degrees of freedom.The minimum number of sensors should be used to obtain as much structural response information as possible,so it is of great engineering significance to optimize the sensor layout of transmission towers.The research contents of this paper are as follows:(1)The basic principles and optimization steps of the effective independent method(EFI),effective independent driving point residual method(EFI-DPR),effective independent average acceleration amplitude method(EFI-AAA)and particle swarm optimization algorithm are analyzed in detail.And three evaluation criteria for optimal sensor placement are modal guarantee criterion,modal kinetic energy criterion and singular value index.(2)Taking the Xiaowan-Heping 500kV transmission line of Yunnan Power Grid as the background,and taking the cat’s head straight line tower and the dry-type tension tower as the research object,APDL module of AN SYS platform and Beam188 beam element are used to conduct 1:1 equal scale modeling for the two transmission towers in the way of direct modeling.Block Lanczo method is used to analyze the modal of the two transmission towers,and the first 15 order modal parameters are extracted respectively.The modal analysis results show that the transmission tower vibration is mainly concentrated in two horizontal directions(along line and transverse line),so the optimal sensor layout of transmission tower can only consider the modal shapes of the transmission tower along line and transverse line.(3)The 2-norm change rates of the first 15 order modal matrices of the two transmission towers were calculated by the Fisher information matrix 2-norm method,and the first 8 order modal matrices of the transmission towers were selected according to the calculation results to optimize the sensor layout.(4)Taking two transmission towers as the research object,EFI method,EFI-DPR method,EFI-AAA method and improved particle swarm optimization algorithm(PSO)with adaptive inertia weight were respectively used to optimize the sensor layout.The modal guarantee criterion,modal kinetic energy criterion and singular value index were used to analyze and compare the methods.The three evaluation criteria were normalized and analyzed,and the optimal layout results were as follows:25 sensors were used in the cat-head linear tower,and 8 sensors were used in the dry-type tensile tower.