Numerical Calculation Of There-dimensional Electric Field And Optimal Design For 1100kV Class B Earthing Switch

In places of high-voltage electrical appliances,complex space electromagnetic fields can generate extremely high induced voltages on conductors,even if isolating live parts using isolated switches,The voltage and current generated by conductor induction on the equipment being repaired is also enough to cause harm to the maintenance personnel.Therefore,the grounding switch must be used to reliably ground the repaired parts.In modern power systems,in order to reduce line corridors to reduce the cost,more and more transmission lines use double or multiple lines on the same tower.In the case of a long line,the coupling between the two lines will be very serious,so that when a line is charged with another line with a grounding switch to open and close the ground,you need to open and close a relatively large inductive voltage and induced current.The grounding switch with high opening and closing parameters is called a Class B grounding switch.In practical projects,Class B grounding switches are widely used in 220-800 kV voltage systems.Both research and use are relatively mature.In this paper,The 1100 kV Class B grounding switch of Chengde UHV series stringers studied is the first in the world.It is the first product developed at home and abroad without any ready-made experience.Therefore,it is necessary to simulate and calculate the electric field with related software to guide the development and optimization of the prototype.In this paper,the three-dimensional electric field of the 1100 kV grounding switch is numerically calculated for various types of breakdown phenomena that occur in the type test of the outdoor UHV AC grounding switch of the JW-1100 type,and Various optimization design schemes is proposed for multiple switch parts that are prone to generate corona discharges.The optimized switch is again numerical calculated until finally the electric field values at various parts of the switch surface are controlled within a safe range.These numerical calculation results have theoretical guiding significance for the development and research of switches.This article first introduces the research background,research objectives,research methods,and research status of the subject.Second,this paper systematically and comprehensively summarized the related theoretical knowledge of the isolated switch and grounding switch;then introduced the electric field theory involved in the calculation of the electric field of the grounding switch and the ANSYS software;then detailly introduced the establishment process of the the grounding switch model in SolidWorks software and the use of APDL in ANSYS for model simplification,model processing,and electric field calculation,and then analyzed the calculation results of the surface electric field of each part of the grounding switch;and it is found that multiple parts of the grounding switch beyond control Field strength because of the influence of the main circuit high voltage.Since the moving contact is close to the high voltage side of the switch,the high voltage electric field has a great influence on it,while the high voltage side equalizing ring has a weaker shielding effect,Therefore,the electric field at the moving contact end face is extremely large.Finally,an optimized design is performed for reducing the field strength of the various parts of the switch,mainly from adjusting the pipe diameter,ring diameter,disk diameter,shell wall thickness,the distance of the fracture of the grounding switch,the distance between the main circuit and the auxiliary circuit,and the position of the control field.These aspects of the structure itself.So that the switch surface field strength can work properly under extreme conditions and normal conditions.The research results have certain guidance and reference value for the prototype development and optimization of the megavoltage grounding switch.