The Equivalent And Impact Of Connecting Accessory In Enclosure EMC Analysis

Electronic system is increasingly becoming complex and enormous with the development of science and technology. Due to that connectors and cables are employed to link the subsystems in independent shielded enclosure. Since the connectors and cables are the main Electromagnetic interference(EMI) coupling path, They become the significant factor which produce radiated interference in a well shielded enclosure. Therefore complexity of simulation model, damage of shielding effectiveness, electromagnetic susceptibility of inner electronic system are caused. This paper concentrated on the model of connecting accessory in electromagnetic simulation model and the EMS problem of inner electronic system.Considering the conventional simplified method can’t deal with connectors and cables for they effect the electromagnetic field distribution by radiation. The author proposed the equivalent dipole simplification method that adopt the dipole radiation source to substitute the radiation effect of connectors an cables, That make the electromagnetic model more reliable. Then partial element equivalent circuit method(PEEC) and analytic formula are applied to calculate the dipole moment.After that base on the idea that divide the shielded enclosure into main part of enclosure and connecting accessory, A shielding effectiveness simulation process that combine the equivalent dipole method and existing simplification theory is put forward. In this method the main part of enclosure is handled by the conventional method however the connectors and cables are modeled with the proposed method. Then three numerical examples are presented to certificate the proposed modeling process can efficiently reduce the computer resource consumption.A testing experiment of multi-pin connector is conducted that prove the PEEC model of multi-pin connector is modeled accurately. Shielding effectiveness of an enclosure is also tested in a 5m microwave darkroom. The result validated the proposed method is correct.Aiming at the inner electronic system EMS Problem induced by the EMI energycoupling of cables. The application of conventional MOM-MNA hybrid is restricted in the high frequency band for MNA is used only in low frequency band. Then a replacement of MNA by PEEC is proposed in this paper. That improve the calculation precision of MOM-MNA in high frequency band.