Uncertainty Analysis Of Electromagnetic Coupling Effect Of Interconnection Cables In Shielded Electronic Equipment

The primary function of electronic equipment enclosure is to provide mechanical protection and electromagnetic shielding for sensitive components.However,with the intelligent and integrated functions of electronic equipment,the density of internal components and interconnecting cables has increased dramatically,resulting in an increasingly serious problem of electromagnetic interference in enclosure.Previous researches mainly focus on the electromagnetic coupling in enclosure with deterministic input parameters.In fact,there are great uncertainties in the geometric structure and material properties of cables as well as the nature of interference field in enclosure.Therefore,field-to-wire coupling problem in enclosure,crosstalk and field-to-wire coupling problem in enclosure under uncertain conditions are studied in this paper.Corresponding calculation models are proposed,which provide a theoretical basis for the suppression of electromagnetic interference in electronic equipment enclosure.Specifically,the main research contents are as follows:(1)Calculation method for field-to-wire coupling in enclosureTo handle the problem of field-to-wire coupling in enclosure,the eigenmode solution method is used to calculate the electric field distribution in enclosure under the excitation of the Hertzian dipole and the symmetrical dipole.The field-to-wire coupling models of two-conductor transmission lines and multi-conductor transmission lines in enclosure are established respectively by means of transmission line theory.A calculation method that can accurately predict the electromagnetic coupling effect of cables in enclosure is proposed.The validity and accuracy of the analytical method are verified using the electromagnetic simulation software FEKO.(2)Uncertainty analysis method for crosstalk effect of cables in enclosureIn order to deal with the crosstalk problem between cables under uncertain conditions,a surrogate model is established based on the polynomial chaos method,which analyzes the crosstalk problems of multi-conductor transmission lines under uncertain conditions.The results are in good agreement with the numerical results calculated by Monte Carlo approach.It turns out that the surrogate model can effectively simplify the original model,whose efficiency is greatly improved on the premise of ensuring accuracy.(3)Uncertainty analysis method for coupling effect of cables in enclosureIn order to handle the field-to-wire coupling problem of cables in enclosure under uncertain conditions in enclosure,stochastic field-to-wire coupling models of twoconductor transmission lines and multi-conductor transmission lines are established respectively with geometrical parameters of cables being random variables.The stochastic models are based on the field-to-wire coupling theory and polynomial chaos method,and Monte Carlo approach is used to validate the models.Compared with Monte Carlo approach,the computational efficiency of the proposed method for statistical analysis of the field-to-wire coupling effect of two-conductor transmission lines can be increased by about 2 times,and the efficiency of multi-conductor transmission lines can be increased by more than 500 times.As the complexity of the field-to-wire coupling problem increases,the proposed method is expected to achieve greater efficiency advantages.