| High voltage electroscope is a tool that can test whether the conductor carries high voltage,which is of great significance to ensure the safety of workers and the safe and stable operation of power system.However,the most commonly uses contacting high-voltage electroscope generally requires battery power supply,and the voltage polarity and voltage level distinction are too obvious,which makes the electroscope extremely inconvenient to use.In addition,because the internal electronic components of the non-contact high-voltage electroscope are susceptible to overvoltage,the reliability of the electroscope is low.With the continuous expansion of the power grid,the amount of electrical inspection operations has increased dramatically.It is of great significance for the operation and maintenance costs of the power system to research and develop a convenient,low-cost,and highly reliable highvoltage electroscope.Aiming at the shortcomings of the current electroscope,a charged rotating high voltage charged indicator based on the thrust effect of corona discharge is designed.The indicator includes a vertical fixed bracket,a thimble with limit,a light stainless steel rotating electrode with an extremely fine needle tip,and a stainless steel reflective sheet.When the indicator is fixed on or in contact with the high-voltage conductor by the fixed support,the freely rotating fine stainless steel electrode tip on the thimble generates corona,and the fine stainless-steel electrode continues to rotate under the action of corona thrust,thereby indicating whether the is measured conductor carries a dangerous high voltage.Firstly,a two-dimensional axisymmetric needle tip model and a three-dimensional model of transmission line and rotating indicator under different erection modes are constructed by AutoCAD.The COMSOL Multiphysics simulation software is used to calculate and analyze the particle density distribution law at the front end of the needle tip,indicating that the rotating thrust of the high-voltage conductor charged rotating indicator comes from the space charge generated at the front end of the needle tip during corona discharge.The influence of the environmental electric field on the electric field of the rotating indicator after the rotating indicator is installed on the transmission line is examined to test the feasibility of the installation of the indicator.In addition,the influence of the rotating indicator on the environmental electric field after the rotating indicator is installed on the transmission line is also examined to test whether the intervention of the indicator has dangerous distortion to the environmental electric field and ensure the safety of the electric inspection operation.Numerical calculations show that after the rotating indicator intervenes in the environmental electric field,the electric field at the tip of the rotating indicator and the overall electric field distribution of the environment are extremely distorted.Secondly,in order to ensure that the high-voltage charged rotating indicator can be reliably started at 10 k V and above voltage levels,COMSOL Multiphysics software is used to simulate and calculate the influence of various factors on the torque of the rotating indicator under different erection methods.According to the simulation results and engineering practice,the actual parameters of the needle tip specification of 0.20 mm,the torsion arm length of 60 mm,and the rotation height of 35 mm are selected.Finally,a high-voltage charged rotating indicator for verification is made and an electrical test is carried out.The response rules under different voltages,different needle tip specifications,different torsion arm lengths and other parameters are examined.Compared with the simulation results,the comparison results show that the two are in good agreement,and the starting voltage of the rotating indicator of the semi-circular curved blade is lower.The designed high-voltage charged rotating indicator has the advantages of AC and DC universal,no battery power supply,low cost,light weight,and can reliably indicate whether the 10 k V and above overhead transmission lines are charged.It can provide live warning for high-voltage power maintenance personnel in time,and has high practical value. |
