Research On The Coupling Effect Of High Power Electromagnetic Pulses On Spaceborne Solar Cells

With the rapid development of military science and technology,the possibility of space satellite spacecraft facing the threat of high power electromagnetic pulse is becoming more and more.As an essential power supply system unit for satellite spacecraft,solar cells are bound to become the focus of the attack.Therefore,it is necessary to research the electromagnetic pulse coupling effect of solar cells on the basis of clarifying the mechanism of electromagnetic pulse coupling.Starting from the electromagnetic pulse coupling mechanism and the material structure characteristics of solar cells,this paper combines theoretical analysis and numerical simulation,and conducts research and analysis from three perspectives:time-domain frequency-domain coupling,cell frequency response characteristics,and multiphysics field effects.The research results provide a certain reference for the electromagnetic damage experiment of solar cells and the design of high-power electromagnetic protection.In this paper,the transient coupling field distribution and the coupling voltage between electrodes are analyzed from the perspective of time domain,and qualitatively judged the sensitive parts of the solar cell.It can be seen from the results that the transient coupling field inside the solar cell can reach 10~6V/m and the coupling voltage between the electrodes can reach more than 150V under the excitation of the electromagnetic pulse with the amplitude of 50kV,which may cause dielectric electrical breakdown.In addition,the coupling field is mainly distributed at the edge of the battery.Then,according to the time domain coupling results,the frequency domain field probes are set at typical positions,and the frequency domain coupling characteristics are analyzed by combining the structure of the solar cell and the corner effect.The simulation results show that the solar cell is more sensitive when the polarization direction of the electromagnetic pulse is perpendicular to the gate line,and the shielding property at the same position is about 20d B different from that when the polarization direction is parallel to the gate line.In addition,the coupling fields at the edges and corners of solar cells are similar.Then,based on the principle of plane absorbing cell structure,the frequency response characteristics of solar cell structure to electromagnetic wave in 0-10GHz broadband band were analyzed.Through theoretical analysis and simulation,the reflection and transmission characteristics of the infinite grid structure of the same size as the solar cell grid line are analyzed,and the similarity between the reflection and transmission of the solar cell grid line unit and the infinite grid structure is compared.The excitation of the solar cell and the reflection and absorption resonance characteristics of the solar cell are analyzed by the two polarized electromagnetic waves of TE and TM at the absorption peak frequency.It can be seen from the results that the absorption of electromagnetic waves by solar cells is polarization-selective.The TE polarization electromagnetic waves are mainly concentrated in the low frequency band of 0-2GHz,while the absorption of TM-polarization electromagnetic waves is in the periodic form of point frequency in the wide band.In addition,the solar cell is excited by the spatial electromagnetic wave at the resonance frequency of the two polarized electromagnetic wave absorption,forming a strong coupling current at the edges on both sides and radiating electric field outwards,causing the electromagnetic wave antinode on the incident wave side to shift to a traveling standing wave distribution.Afterwards,the influence of the structural parameters of solar energy on electromagnetic wave absorption was studied.It can be seen from the results that reducing the grid line density,using a high dielectric constant anti-reflection film and reducing the thickness of the anti-reflection film can all reduce the absorption of electromagnetic waves by the solar cell.Finally,COMSOL is used to analyze the electric-thermal-deformation multi-physics coupling effect of solar cells under electromagnetic pulse irradiation.The results show that the high power electromagnetic pulse will produce a certain thermal effect on the solar cell and cause a certain degree of deformation of the grid line layer of the solar cell.On this basis,the influence of electromagnetic pulses with different polarizations and excitation parameters on the temperature field distribution of the solar cell and the temperature change of each layer structure is analyzed.The results show that the thermal effect of electromagnetic pulses perpendicular to the polarization direction of the grid line,high frequency and long pulse width is more obvious.Afterwards,the electrothermal coupling of repetitive frequency pulses under the same environment was studied.The results show that the amount of electrothermal coupling generated under the excitation of the repetitive pulse is much greater than that of a single pulse.In the case of limited heat dissipation,the temperature curve will gradually increase and eventually reach the melting point of the metal grid line,causing the grid line to fuse thermally.