Research On 24kV Switchgear Cabinet Strength Simulation And Optimization Based On Internal Arc Fault Test

24kV switchgear is a kind of power equipment with a very wide range of applications,and it plays a very important role in the power system.However,due to differences in the design level,manufacturing process,and installation methods,the quality of the products is uneven,and many problems have been exposed during the operation.The internal arc fault of the switchgear is an inevitable and destructive fault.Once it occurs,it will bring great harm to personal safety and electrical equipment.Using simulation and experiments to study and analyze the internal arc fault and cabinet strength of the switchgear can effectively reduce the occurrence of arc faults and improve the safety of the switchgear.This paper takes XGN102-24(Z)/T630-2524 kV switchgear of Xiamen Huadian Switchgear Co.,Ltd.as the object.Based on the pressure relief value obtained in the inflation experiment,ANSYS is used to carry out finite element simulation and optimization of the strength of the switchgear cabinet.Research,so as to provide a theoretical basis and reference for the design and optimization of high-performance switchgear cabinet structure.The main work of the thesis is as follows:(1)Use Solidworks to establish the geometric model of the switchgear,and use ANSYS Workbench to perform finite element simulation on the gas chamber and cable room of the switchgear,analyze the strain change rule when the pressure is relieved,and obtain the pressure relief simulation value of the switchgear.The results show that the strain distribution of the switchgear gas chamber and cable room is consistent with the actual situation when subjected to static load,and with the increase of the pressure in the cabinet,the deformation of each part also increases.When the pressure in the air chamber and cable chamber reaches 0.09 MPa,0.1MPa,the pressure relief plate will be flushed to release the pressure.And through the pressure relief valve deformation measurement experiment and the inflation experiment,the simulation method and simulation value of the pressure relief value of the switchgear are verified.(2)Since the product itself is designed with a timely pressure relief structure,the maximum pressure generated by the internal arc fault of the switchgear will not exceed twice its pressure relief value.Therefore,the finite element model of the switchgear is established using ANSYS Workbench,and the cabinet strength simulation analysis of the switchgear is carried out with the double pressure relief value as the static load.The simulation results show that the deformation of the finite element model under pressure is consistent with the roof measurement experiment,the principal stress distribution is consistent with the water pressure experiment,and the switchgear cabinet can withstand twice the pressure relief value.In addition,the strength of the switchgear cabinet is checked and calculated using the first strength theory.The check results proved that the cabinet strength of the switchgear meets the requirements and can withstand the huge impact caused by the internal arc fault of the switchgear.(3)Carry out the corresponding internal arc fault test in the test station,and measure the maximum pressure value of the arc fault in the cable room and gas chamber of the switch cabinet during the test.The test results show that the maximum pressure of arc faults in the cable room and gas room of the switchgear is 0.16 MPa,which is less than twice the pressure relief value.After the test,the indicators around the cable room and gas room are intact and the test is qualified.This test verifies the correctness of the intensity simulation of the switchgear cabinet.(4)Finally,the strength of the gas chamber is optimized according to the impact force on the part of the air chamber during the simulation of the strength of the switchgear cabinet.By changing the fillet radius of the left and right side panels,the length of the left and right side panel stiffeners,and the number of top panel stiffeners,we compare and analyze the impact force received by different air chambers in the cabinet strength simulation process,and finally choose the left and right side panel fillet radius 35 mm,The length of the ribs on the left and right side plates is shortened by 20 mm,and the number of ribs on the top plate is one air chamber,which minimizes the impact force on the cabinet body and achieves the optimization effect.