Analysis Method Of Large Scale Space Shielding Effectiveness And Research On HVDC Hall Shielding Technology

Supported by National Natural Science Foundation of China under grant NO.50777017, the research on shielding effectiveness of large scale space and HVDC hall is mainly studied in this paper. Firstly,electromagnetic field numerical calculation method(FEM,FDTD,FIT,MoM),principle of electromagnetic shielding(E-field,M-field and EM shielding),influencing factors of shielding effectiveness,numerical method of Aperture coupling,calculation program of antenna based on MoM are analysed separately and the feasibility of using MoM method to analyze the shielding effectiveness(SE) of the large scale shielding body is researched. Secondly,through the establishment of large space shielding model,MoM method is used to calculate the SE of shielding body with different apertures,different slots,different lap structures and different shielding material. SE distribution is analysed in the large scale shielding space owing to its large characteristic. Then the numerical and experimental method both are used to verify the correctness and the accuracy of the method used in this paper.Based on the analysis above,the HVDC hall model is established according to structure parameter of one actual HVDC converter station.The SE of shielding gate,lapjoint and wall bushing are calculated mainly and contrasted with measuring data,and the hall model is confirmed correctly. Finally,some improved measures for the SE of the large scale shielding body and HVDC hall are presented based on the previous calculation and analysis.