Study On Surface And Internal Charge And Discharge Effects Of GEO Satellite

The solar activity seriously affects the plasma environment of the geosynchronous orbit(GEO)height and a large number of satellites are clustered in this area.When the satellites are running in this orbit,they will interact with the space plasma and high-energy electronics environment to generate surface and internal charging and discharging phenomena,which will cause satellite failure.This paper will study the surface and internal charging and discharging effects of GEO satellites against this background.The charging effect of satellite surface is divided into absolute charging and unequal charging.Absolute charging refers to the charging phenomenon of the whole variation of the satellite’s potential,while unequal charging refers to the charging phenomenon of different potentials in different parts of the satellite.A more detailed charging and discharging process on the satellite surface is unequal charging compared to absolute charging.Based on the size and material of different parts of the actual satellite,a three-dimensional geometric model is constructed.Particle-In-Cell(PIC)algorithm is used to simulate the unequal charging and discharging of satellite surface in the calm and active phase of solar activity.At the same time,the selected satellite components are solar panels with small spacing between each other.The potential of each satellite solar panels during the quiet and active periods of solar activity and the change of the potential difference between the panels are mainly calculated and analyzed.When a high-energy electron beam is incident on the surface of GEO satellite,a large amount of charge accumulates inside the dielectric material and isolated conductor of the satellite,resulting in deep dielectric charging and discharging in the electric field.For the factors that affect the deep charging and discharging degree of the dielectric,this paper calculates the maximum electric field in the dielectric to reflect the degree of influence,and focuses on the influence of the incident angle of high-energy electron beam on the maximum electric field in the dielectric.The effects of shielding layer and dielectric thickness,electron beam energy and shielding layer material on the model are also considered.The Monte-Carlo(MC)method and corresponding software package are used to build the deep charging and discharging model of the shield-media three-dimensional planar plate,and the back of the plate is grounded.With or without the shield layer protection,the deposition state of charges in the media under different angles and different energy incidence of high-energy electron beam is analyzed,and the maximum electric field in the media under different conditions is calculated.At the same time,change the shielding layer material to explore the protection effect of different materials on the media.The first part simulates the unequal charging and discharging process on the surface of GEO satellite.The results show that the lower charge balance potential of solar panels and the smaller charge difference between the panels do not affect the normal operation of the satellite in the plasma environment during the calm period of the sun.However,in the plasma environment during the active phase of the sun,the satellite solar panels are subject to very strong interference,the charge balance is destroyed,and the potential at the irradiated area drops rapidly and there is a large potential difference between adjacent structures.It is easy to cause electrostatic discharge to harm the normal operation of the satellite.The results of the second part on the deep charging and discharging effects of satellite media show that,with or without shielding layer,the number of deposited charges in the media increases first and then decreases with the increase of depth,and at the same time,with the increase of the angle of electron incidence,the maximum charge deposition increases in turn and the maximum deposited position shifts to the ungrounded end.For the 0.1MeV-1MeV electron beam with the largest proportion of high energy electrons in space,the maximum electric field value increases with the increase of the angle of incidence of electrons when there is no shield layer,and decreases with the increase of the angle of incidence of electrons when there is a shield layer.In the presence of shielding layer,with the increase of the energy of the incoming electrons,the value of the maximum electric field in the medium increases first and then decreases,and the higher the angle,the higher the energy value reaches the peak of the maximum electric field.It is more appropriate to use materials with high atomic number as shielding layer.