The previous study of the optimization research of electromagnetic repulsion efficiency is mainly focused on the structural optimization and parameter matching of such key elements as repulsion disks and coils

as well as the optimization analysis of the voltage and capacitance of precharged capacitors. While the analysis and study on the influence of auxiliary support structure of switch on efficiency is less. Auxiliary supporting structural parts of different materials and sizes have a non-negligible effect on the efficiency of the repulsion disk. In this paper

the fast switching support plate is taken as the analysis and research object. It is proposed under the premise of not changing structure of the prototype to reduce the eddy current loss of the support plate and improve the electromagnetic repulsion efficiency by designing the magnetic conductive plate and slotting the support plate. Finally

based on the simulation results

the improvement design of a 110 kV double-break fast switch prototype is made on the basis of the simulation result. The test results show that

in the case of keeping capacitance unchanged

addition of the magnetic conductive plate or the slot of the supporting plate can effectively reduce the precharged voltage of the capacitor and improve efficiency of the repulsion mechanism.