A method for assessing and monitoring the risk of deep charging of satellite internal dielectrics

Abstract

The present invention provides an assessment and monitoring method for the deep charging risk of satellite internal medium. The high-energy electron spectrum parameters are estimated by measuring the electron flux and the commonly used standard energy value. The 24-hour time is divided into a number of predetermined moments. The energy of high-energy electrons of two different energy channels at the predetermined moments is obtained and the surface electron flux is calculated. The shielding thickness of the internal medium is obtained. The lower energy limit E of the deposition is calculated according to the statistical relationship between the maximum range and energy of the electron. min , and the critical thickness of the internal medium for electron deposition is calculated. The energy upper limit E for deposition is calculated through the inequality between the critical thickness and the energy upper limit condition. max , obtain the satellite circuit board area S and the internal medium resistance R, according to the area S, resistance R, energy lower limit E min and energy limit E max The voltage value and voltage value formula are used to calculate the voltage value U at the predetermined level. This enables effective assessment and continuous monitoring of satellite deep charging risks, making the assessment more accurate and efficient.

Description

Technical Field

[0001] The present invention relates to the technical field of satellite internal medium charging, and in particular to a method for assessing and monitoring the risk of deep-layer charging of satellite internal medium. Background Art

[0002] There are a large number of application satellites in orbit in the Earth's space. Since they are always in the outer radiation belt, high-energy electrons in space not only cause radiation dose effects on satellites, but also penetrate the satellite skin and deposit in the satellite's internal insulating materials or non-grounded conductors to cause charging, that is, deep charging of satellites. Satellite deep charging is like ground static electricity. When it exceeds a certain tolerance value, it will produce discharge, just like ground static electricity discharge. During the discharge, a large amount of charge and electromagnetic waves will be released in a short time. This type of static electricity discharge will directly or indirectly couple into the electronic system and cause harm. Satellites affected by deep charging may experience abnormal phenomena such as jumps, and even in severe cases, the entire satellite may fail. The detection results of the Fengyun-4 satellite show that the KV-level events simulated in the early theory will not occur in the circuit board material, but the higher voltage may interfere with the operation of a single machine, and a new evaluation method is needed.

[0003] The assessment of deep charging of satellite internal media in the existing technology usually cannot effectively assess the severe situation of charging of satellite internal media, and it is easy to cause excessive or insufficient assessment of the harm of deep charging to the satellite, and it is also impossible to achieve continuous monitoring and assessment of deep charging risks. Summary of the invention

[0004] In view of the above-mentioned shortcomings of the prior art, the purpose of the present invention is to provide a method for evaluating and monitoring the deep charging risk of the satellite internal medium. The method of the present invention can effectively evaluate the deep charging voltage of the satellite internal medium, and can realize continuous monitoring and evaluation of the deep charging risk of the satellite internal medium. The technical solution adopted by the method of the present invention is as follows:

[0005] The present invention provides a method for assessing and monitoring the risk of deep-layer charging of satellite internal media, the method comprising the following steps:

[0006] Obtain the surface electron fluxes F1 and F2 of the two energy channels of the internal medium of the satellite to be measured, and substitute the surface electron fluxes F1, F2 and the commonly used standard energy values ​​E1 = 0.8 MeV and E2 = 2 MeV into the high-energy electron differential energy spectrum formula: F = AE B , the high energy electron spectrum parameters A and B are calculated;

[0007] Divide 24 hours into a number of predetermined moments on average, and use a satellite high-energy electron detector to obtain the energies E3 and E4 of high-energy electrons of two different energy channels incident on the satellite internal medium at the predetermined moments;

[0008] Get the shielding thickness r of the satellite's internal medium o , according to the statistical relationship between the maximum range L of the electron and the electron energy E and the statistical relationship between the critical thickness a of the protective layer where the electron flux attenuates and the electron energy E: The internal medium is calculated to be within the shielding thickness r o The lower energy limit of electron deposition is E min and the critical thickness a of the protective layer where the electron flux decays, where r o The unit of L and a is g / cm 2 , the unit of E is MeV;

[0009] Obtain the shielding distance x between the inspection layer inside the circuit board and the outer surface of the satellite, according to the energy upper limit condition inequality: x <L(E max ) and the energy lower limit inequality: x≥L(E min )-a(E min ), the upper limit of the energy for deposition E is calculated max , where x is in g / cm 2 , L(E max )、L(E min ) are the maximum range of electrons when the electron deposition energy reaches the upper and lower limits, respectively, a(E min ) is the critical thickness when the electron deposition energy reaches the lower limit;

[0010] Obtain the circuit board area S of the satellite and the resistance R of the internal medium, and convert the circuit board area S, the resistance R, and the energy upper limit E max and the energy lower limit E min Substitute the following formula to calculate the voltage value of the predetermined level:

[0011] The predetermined voltage range is divided into four risk levels: no risk, low risk, medium risk and high risk. The risk level is evaluated according to the voltage value, and chart data is generated based on the voltage value obtained at each predetermined time and the evaluated risk level.

[0012] Further, using a satellite high-energy electron detector to obtain the energies E3 and E4 of high-energy electrons of two different energy channels incident on the satellite internal medium at the predetermined time includes:

[0013] Dividing the energy spectrum of the high-energy electrons into two energy intervals with different energy values ​​according to the detection energy of the satellite high-energy electron detector;

[0014] The median of the electron energy in each energy interval is taken as the energies E3 and E4 of the high-energy electrons in the energy channel.

[0015] Further, the shielding thickness r of the satellite internal medium is obtained o , according to the statistical relationship between the maximum range L of the electron and the electron energy E and the statistical relationship between the critical thickness a of the protective layer where the electron flux attenuates and the electron energy E: The internal medium is calculated to be within the shielding thickness r o The lower energy limit of electron deposition is E min The critical thickness a of the protective layer where the electron flux attenuates includes:

[0016] Calculate the electron flux change rate of each energy channel of high-energy electrons passing through the satellite shield with a thickness of r0 The unit of r0 is g / cm 2 .

[0017] Further, the shielding thickness r of the satellite internal medium is obtained o , according to the statistical relationship between the maximum range L of the electron and the electron energy E and the statistical relationship between the critical thickness a of the protective layer where the electron flux attenuates and the electron energy E: The internal medium is calculated to be within the shielding thickness r o The lower energy limit of electron deposition is E min and the critical thickness a of the protective layer at which the electron flux attenuates, further comprising the following steps:

[0018] The electron flux f1, F2 of each energy channel is calculated by the surface electron flux F1, F2 and the electron flux change rate ratio. : :f1=F1×ratio and f 2: :f2=F2×ratio;

[0019] The total electron flux F reaching the surface of the satellite's internal medium is calculated as: F = f1 + f2;

[0020] Substitute the total electron flux F into the high-energy electron differential energy spectrum formula: F = AE B , calculate the corrected electron energy E′, and then use the electron energy E′ to calculate the voltage value.

[0021] Furthermore, the method further includes continuously monitoring the charging voltage of the satellite's internal medium. Furthermore, the method further includes continuously monitoring the charging voltage of the satellite's internal medium, including the following steps:

[0022] Obtaining an initial voltage U1 of the satellite internal medium;

[0023] Calculate the voltage change du of the satellite internal medium, du = (SFQ E -Ut / R) / C;

[0024] Obtain the charging voltage U of the satellite internal medium at the observation time t t ;

[0025] According to the charging voltage U at the observation time t t Calculate the charging voltage U of the satellite internal medium at the next observation time t+1 t+1 , U t+1 =U t +du;

[0026] Where S is the detection area of ​​the satellite's internal medium, in cm 2 ;Q E is the electron charge, C is the capacitance of the satellite's internal medium; F t is the total electron flux at the above observation time t.

[0027] Furthermore, the method further comprises the following steps:

[0028] If the high-energy electron monitoring data and / or high-energy electron model operation process is continuous, the calculation is performed continuously and the deep charging file is generated regularly;

[0029] If the high-energy electron spectrum data is interrupted, the calculation of the charging voltage is interrupted.

[0030] Furthermore, the method further comprises the following steps:

[0031] When the calculation of the charging voltage is interrupted, a deep charging file is generated and pushed out.

[0032] Furthermore, the method further comprises the following steps:

[0033] Generate files regularly and push said files out to the deep charge files.

[0034] As described above, the method for assessing and monitoring the risk of deep charging of satellite internal medium provided by the present invention has at least the following beneficial technical effects:

[0035] The method of the present invention can calculate the deep charging voltage of the satellite's internal medium based on the electron flux reaching the surface of the medium, thereby evaluating the deep charging voltage of the satellite's internal medium. If the deep charging voltage exceeds the equipment safety prefabrication, the materials of the satellite's internal medium can be screened or shielding measures can be optimized in a targeted manner, thereby finely ensuring the safe operation of the equipment. Compared with related technologies, it realizes effective assessment and continuous monitoring of the deep charging risk of the satellite's internal medium, with more accurate assessment results, higher assessment efficiency, and more convenient risk monitoring, which improves the user experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 is a flow chart of a method for assessing and monitoring deep charging risk of satellite internal medium provided according to an embodiment of the present invention;

[0037] Figure 2 The present invention provides a flowchart of a method for assessing and monitoring the risk of deep charging of satellite internal media according to an embodiment of the present invention. DETAILED DESCRIPTION

[0038] The following describes the embodiments of the present invention through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention.

[0039] It should be noted that the illustrations provided in this embodiment only illustrate the basic concept of the present invention in a schematic manner. Although the illustrations only show components related to the present invention rather than being drawn according to the number, shape and size of components in actual implementation, the form, quantity, positional relationship and proportion of each component in actual implementation can be changed at will under the premise of realizing the technical solution of this party, and the component layout form may also be more complicated.

[0040] Embodiment 1

[0041] This embodiment provides a method for assessing and monitoring the risk of deep-layer charging of satellite internal media. Figure 1 and Figure 2 , the method comprises the following steps:

[0042] Step S10, obtaining the surface electron fluxes F1 and F2 of the two energy channels of the internal medium of the satellite to be tested, and respectively substituting the surface electron fluxes F1, F2 and the commonly used standard energy values ​​E1=0.8MeV and E2=2MeV into the high-energy electron differential energy spectrum formula: F=AE B (1), the high-energy electron spectrum parameters A and B are calculated.

[0043] Specifically, the high-energy electron differential energy spectrum formula: F = AE B (1) F is the high-energy electron flux with energy E in the orbit, in cm -2 s -1 sr -1 MeV -1 , the unit of E is MeV, A and B are constants.

[0044] Generally speaking, standard high-energy electron data usually give integrated fluxes with energies greater than 0.8MeV and greater than 2MeV. The characteristic parameters A and B of the energy spectrum can be calculated and derived from the above two given integrated fluxes.

[0045] In the specific implementation process, the high-energy electron integrated fluxes of E>0.8MeV and E>2MeV are set as F1 and F2 respectively, and the surface electron fluxes F1 and F2 of the two energy channels of the internal medium of the satellite to be measured, as well as E1=0.8MeV and E2=2MeV, are substituted into the energy spectrum parameter formula: get Substitute B into the formula: A = -F1 × (B + 1) / E1 B+1 (4), and A is calculated.

[0046] Step S20, 24 hours are evenly divided into a number of predetermined moments, and the satellite high-energy electron detector is used to obtain the energies E3 and E4 of high-energy electrons of two different energy channels incident on the internal medium of the satellite at the predetermined moments.

[0047] In a preferred embodiment of the present invention, the 24 hours are evenly divided into 144 predetermined moments, that is, the incident high-energy electrons are acquired and their energy is measured every ten minutes, so as to realize continuous observation and measurement of satellite high-energy electron incidence.

[0048] In the specific implementation process, for example, the energy spectrum of the high-energy electrons can be divided into two energy intervals with different energy values ​​according to the detection energy of the satellite high-energy electron detector, and the median of the electron energy in each energy interval is used as the energies E3 and E4 of the high-energy electrons in the energy channel; or, using high-energy electrons with a specific energy spectrum, the energy spectrum can be divided according to the different energy channels of the satellite high-energy electron detector to obtain two energy intervals with different energy values, and the median of each energy interval is used as the energies E3 and E4 of the high-energy electrons in the energy channel.

[0049] Step S30: Obtain the shielding thickness r of the satellite internal medium o , according to the statistical relationship between the maximum range L of the electron and the electron energy E and the statistical relationship between the critical thickness a of the protective layer where the electron flux attenuates and the electron energy E: a=0.283E(6), and the internal medium is calculated to be within the shielding thickness r o The lower energy limit of electron deposition is E min and the critical thickness a of the protective layer where the electron flux decays, where r o The unit of L and a is g / cm 2 , the unit of E is MeV.

[0050] Step S40, obtaining the shielding distance x between the inner surface of the circuit board and the outer surface of the satellite, according to the energy upper limit condition inequality: x <L(E max )(7) and the energy lower limit inequality: x≥L(Emin )-a(E min )(8), calculate the upper limit of the energy for deposition E max , where x is in g / cm 2 , L(E max )、L(E min ) are the maximum range of electrons when the electron deposition energy reaches the upper and lower limits, respectively, a(E min ) is the critical thickness when the electron deposition energy reaches the lower limit.

[0051] Step S50: Obtain the circuit board area S of the satellite and the resistance R of the internal medium, and convert the circuit board area S, the resistance R, and the energy upper limit E max and the energy lower limit E min Substitute the following formula to calculate the voltage value of the predetermined level:

[0052] Specifically, based on the relationship between the charging voltage and electron flux of the satellite's internal medium and the area and resistance of the charging detector, the deep charging voltage of the satellite's internal medium can be evaluated. The deep charging voltage U of the satellite's internal medium can be obtained by formula (9), where S is the detection area of ​​the deep charging medium, R is the resistance of the deep charging medium, and Q is E is the charge of a single electron, which is 1.6×10 -19 Kulun.

[0053] In the specific implementation process, the flux change rate after the electron flux passes through the protective layer with a thickness of r0 can be expressed as: The unit of r0 in formula (10) is g / cm2. When the charge on a certain layer on the circuit board reaches dynamic equilibrium, the number of electrons deposited on this layer is equal to the number of electrons discharged through the current, that is, The left side of formula (11) is the discharge current deposited on a certain level, U is the voltage of the level, and R is the resistance of the level. Formula (1) gives the high-energy electron flux Φ passing through a certain level, so the electrons deposited on the level can be expressed as It can be seen that the deposition energy is related to the energy of the external incident electrons.

[0054] Furthermore, let the shielding distance from the inner surface of the circuit board to the outer surface of the satellite be x, in g / cm 2 , in order to deposit charge at this level, the lower limit of energy that the electron needs to reach must satisfy: x ≥ L (E min )-a(E min )(8), at the same time, when x exceeds L, the electrons cannot reach and cannot form effective electron deposition. Therefore, the condition for the maximum energy is: x <L(E max)(7), the calculation formula of deposited electrons is:

[0055] Since reasonable assumptions are used in the approximate solution process, substituting into formula (1) and formula (13) can be written as The voltage formed by high-energy electron deposition at a specific level can be calculated by the following formula: Right now Where S is the circuit board area in cm 2 .

[0056] Step S60, dividing the predetermined voltage range into four risk levels of no risk, low risk, medium risk and high risk, performing risk level assessment according to the voltage value, and generating chart data of the voltage value obtained at each predetermined time and the assessed risk level.

[0057] In this embodiment, by calculating the flux change rate, the electron flux incident on the satellite's internal medium can be accurately obtained, and the maximum voltage of the satellite's internal medium, that is, the deep charging voltage, can be accurately obtained through the electron flux, thereby evaluating the deep charging voltage of the satellite's internal medium. If the deep charging voltage exceeds the danger threshold, the material of the satellite's internal medium can be screened or the shielding measures can be optimized in a targeted manner, thereby ensuring the safe operation of the equipment in a refined manner.

[0058] In the preferred embodiment, the high-energy electron detection data of the Fengyun-4 satellite is used as an example to simulate the above calculation process. The instrument used by Fengyun-4 to detect deep charging voltage is made of the same material as most circuit boards inside the satellite. The area of ​​the probe is 5cm 2 , the resistance is 1×1010Ω.

[0059] Taking the detection data at 3:00 UT on January 9, 2017 as an example, the high-energy electron flux at that time was: F1 = 5.6×105cm -2 sr -1 s -1 , F2=8.4×102cm -2 sr -1 s -1 ;

[0060] Substituting into formula (3): The high-energy electron spectrum constant B = -8.15 was obtained;

[0061] Substitute the values ​​of F1 and B into formula (4): A = -F1×(B+1) / E1 B+1 , we get A = 8.12 × 105 cm -2 sr -1 s-1 MeV -1 .

[0062] The shield thickness of the Fengyun-4 deep-charge detector was evaluated to be 0.8 mm aluminum, or 0.236 g / cm 2 . Using the approximation method, from formula (5): Calculate E min =0.594MeV; From formulas (5), (6), (7): a=min(0.283E,L),x <L(E max ), the energy upper limit E of deposition is calculated by the stepwise approximation method. max =1.33MeV.

[0063] Deep charge voltage calculation, E min and E max , and the resistance of the medium are substituted into formula (15): The voltage value of this layer can be calculated to be U = 1.583 V. The reading of the deep charge detector at this moment is 1.52 V.

[0064] In a preferred exemplary embodiment, the Fengyun-4 satellite on April 2, 2017 is taken as an example, and the energy spectrum characteristic parameters of the extraterrestrial high-energy electron flux at 12 time points on the hour are derived using the methods and steps in the implementation scheme, as well as the voltage value of the deep charging detector at that moment calculated based on these parameters and the given method, and compared with the measured values.

[0065] Table 1 shows the calculated results and measured values ​​of deep charge voltage at several time points on April 2, 2017. The parameters of the sedimentation area are the same as those given in the previous section, i.e., E min =0.594MeV, E max =1.33MeV, the calculation results are shown in Table 1:

[0066]

[0067] Table 1

[0068] By comparing the test calculation results, we can see that the trend of the detector voltage calculated by the method given in the embodiment of the present invention is basically consistent with the measured data. Therefore, the method for calculating the deep charging voltage described in the embodiment of the present invention can evaluate the hazards of deep charging in events with high high-energy electrons, and can be fully used to evaluate the risk level of the deep charging voltage of the satellite's internal medium, that is, the above method can be fully used to evaluate the deep charging extreme value that the internal medium of the satellite may reach in the future under the worst high-energy electron environment, and then carry out targeted satellite internal medium material screening and shielding optimization measures. At the same time, the method provided by the embodiment of the present invention has the characteristics of clear process, concise method, fast calculation, and easy-to-understand results, and is suitable for use in satellite design and on-orbit support.

[0069] It can be seen that the satellite internal medium deep charging monitoring method described in the present invention can more effectively evaluate and continuously monitor the deep charging risks of satellite internal media compared with related technologies. The evaluation results are more accurate, the evaluation efficiency is higher, the risk monitoring is more convenient, and the user experience is improved.

[0070] In a preferred embodiment, using a satellite high-energy electron detector to obtain the energies E3 and E4 of high-energy electrons of two different energy channels incident on the satellite internal medium at the predetermined time includes:

[0071] Dividing the energy spectrum of the high-energy electrons into two energy intervals with different energy values ​​according to the detection energy of the satellite high-energy electron detector;

[0072] The median of the electron energy in each energy interval is taken as the energies E3 and E4 of the high-energy electrons in the energy channel.

[0073] In a preferred embodiment, the shielding thickness r of the satellite internal medium is obtained. o , according to the statistical relationship between the maximum range L of the electron and the electron energy E and the statistical relationship between the critical thickness a of the protective layer where the electron flux attenuates and the electron energy E: a=0.283E, and the shielding thickness r of the internal medium is calculated. o The lower energy limit of electron deposition is E min The critical thickness a of the protective layer where the electron flux attenuates includes:

[0074] Calculate the electron flux change rate ratio of each energy channel high-energy electrons passing through the satellite protection layer with a thickness of r0: The unit of r0 is g / cm 2 .

[0075] Preferably, the shielding thickness r of the satellite internal medium is obtained o, according to the statistical relationship between the maximum range L of the electron and the electron energy E and the statistical relationship between the critical thickness a of the protective layer where the electron flux attenuates and the electron energy E: a=0.283E, and the shielding thickness r of the internal medium is calculated. o The lower energy limit of electron deposition is E min and the critical thickness a of the protective layer at which the electron flux attenuates, further comprising the following steps:

[0076] The electron flux f1, F2 of each energy channel is calculated by the surface electron flux F1, F2 and the electron flux change rate ratio. : :f1=F1×ratio(16) and f 2: :f2=F2×ratio(17);

[0077] The total electron flux F reaching the surface of the satellite's internal medium is calculated as: F = f1 + f2 (18);

[0078] Substitute the total electron flux F into the high-energy electron differential energy spectrum formula: F = AE B , calculate the corrected electron energy E′, and then use the electron energy E′ to calculate the voltage value.

[0079] In the embodiment of the present invention, the electron flux change rate under different protective layer thicknesses is calculated based on the relationship between the thickness r0 of the satellite protective layer passed by high-energy electrons and the electron flux change rate ratio, thereby calculating the total electron flux passing through the protective layer under different protective layer thicknesses, and further calculating the corrected electron energy E′, and then calculating the voltage value based on the electron energy E′, thereby improving the accuracy of the electron voltage value calculation and making the evaluation result more accurate.

[0080] It can be seen that the satellite internal medium deep charging monitoring method described in the present invention can more effectively evaluate and continuously monitor the deep charging risks of satellite internal media compared with related technologies. The evaluation results are more accurate, the evaluation efficiency is higher, the risk monitoring is more convenient, and the user experience is improved.

[0081] Embodiment 2

[0082] Based on the above-mentioned embodiment 1, an embodiment of the present invention provides another method for assessing and monitoring the risk of deep charging of the internal medium of a satellite. The method of this embodiment first adopts the same method as the method of embodiment 1 to assess the risk of deep charging of the internal medium of the satellite, and the specific process will not be repeated.

[0083] In the implementation process, it should be noted that when the total electron flux F incident on the satellite internal medium at the first observation time is obtained, the initial charging voltage U1=U0 of the satellite internal medium is given. A large number of experiments have shown that after a certain period of time, the actual charging voltage is only related to the incident electron flux, so the initial voltage can be within a reasonable range.

[0084] In a preferred embodiment, the method further includes continuously monitoring the charging voltage of the internal medium of the satellite.

[0085] Preferably, continuously monitoring the charging voltage of the satellite internal medium comprises the following steps:

[0086] Obtaining an initial voltage U1 of the satellite internal medium;

[0087] Calculate the voltage change du of the satellite internal medium, du = (SFQ E -U t / R) / C(19);

[0088] Obtain the charging voltage U of the satellite internal medium at the observation time t t ;

[0089] According to the charging voltage U at the observation time t t Calculate the charging voltage U of the satellite internal medium at the next observation time t+1 t+1 , U t+1 =U t +du(20);

[0090] Where S is the detection area of ​​the satellite's internal medium, in cm 2 ;Q E is the electron charge, C is the capacitance of the satellite's internal medium; F t is the total electron flux at the above observation time t.

[0091] Specifically, the charge formed by high-energy electrons in the medium mainly includes the voltage formed by the deposition of high-energy electrons. At the same time, since the resistivity of the medium is not infinite, the current caused by the weak electric field formed in the medium causes the loss of charge. Therefore, according to the change in charge in the medium and the capacitance of the medium inside the satellite, the change in voltage du of the medium inside the satellite during the charging process can be calculated. The calculation formula for du is as follows:

[0092] du=(SFtQ E -U t / R) / C(19),

[0093] Where S is the detection area of ​​the satellite's internal medium, in cm 2 ;Q Eis the electron charge, C is the capacitance of the satellite's internal medium; F t is the total electron flux at the above observation time t.

[0094] After obtaining the above charging voltage variation du, the continuous charging voltage value of the satellite internal medium at continuous observation time can be obtained by the following formula:

[0095] U t+1 =U t +du(20).

[0096] The above formula (20) can be used to continuously monitor the charging voltage of the satellite internal medium.

[0097] Generally, the high-energy electron detection data is continuous, and the high-energy electron model runs without interruption. At this time, the high-energy electron flux data is continuously input, providing a continuous high-energy electron energy spectrum, so that the charging voltage of the satellite internal medium can be continuously calculated. At this time, the deep charging file can be generated and launched regularly according to the calculation results.

[0098] When the high-energy electron detection data is abnormal or the high-energy electron model operation is interrupted, resulting in an interruption in the electron flux data, the calculation is interrupted, and a calculation file is generated and a deep charging file is derived based on the calculation results.

[0099] In the preferred embodiment of this embodiment, the Fengyun-4 satellite is also taken as an example to simulate the continuous monitoring of the satellite internal medium charging voltage. In this preferred embodiment, the daily variation of the deep charging voltage of the Fengyun-4 satellite is calculated by taking April 2, 2017 as an example. The relevant parameters of the deep charging detector of the Fengyun-4 satellite are the same as those in the first embodiment, specifically: the satellite protective layer is 0.8 mm thick aluminum; the resistance of the deep charging detector is 1.75×10 12 Ohm; area is 28.3cm 2 The capacitance of the deep charge detector is 4.5 pf. In this preferred embodiment, according to the distribution characteristics of the deep charge voltage of FY-4 (-5.0 V to -0.1 V), the initial voltage U0 of the satellite internal medium is set to -1.0 V.

[0100] First, the electron energy spectrum file of April 2, 2017 was extracted. Based on the electron flux information of the electron energy spectrum file, the total electron flux F incident on the satellite internal medium at each observation time was calculated. t ; The electron flux F t The calculation method of refers to the method in Example 1.

[0101] Then, the charge voltage change du of the satellite internal medium is calculated according to formula (19). Based on the voltage change, the charge voltage U at the observation time t is calculated in turn using formula (20): tand the charging voltage U at the next observation time t+1 t+1 . Until the charging voltage at all observation times is calculated.

[0102] The relative deviation between the calculated value and the measured value of the above charging voltage is calculated by the following formula: Where N is the number of observation moments. The relative deviation between the two is calculated to be 10.9%. This method uses the satellite-measured high-energy electron energy spectrum as input for the first time, and the results obtained are close to the measured deep charging data. Under the premise that the satellite carries high-energy electron detection equipment or the high-energy electron environment model has appropriate accuracy, it can be used to evaluate the deep charging degree of the satellite's internal dielectric materials in real time.

[0103] As described above, the method for assessing and monitoring the risk of deep charging of satellite internal medium provided by the present invention has at least the following beneficial technical effects:

[0104] The method of the present invention can calculate the flux change rate of monoenergetic electrons after passing through the satellite protective layer, calculate the electron flux of a single energy channel according to the flux change rate, and then integrate to obtain the electron flux reaching the surface of the medium. The deep charging voltage of the satellite's internal medium can be calculated according to the electron flux reaching the surface of the medium, thereby evaluating the deep charging voltage of the satellite's internal medium. If the deep charging voltage exceeds the equipment safety prefabrication, the material of the satellite's internal medium can be screened or the shielding measures can be optimized in a targeted manner, thereby finely ensuring the safe operation of the satellite equipment.

[0105] Furthermore, the above method of the present invention can also calculate the change of the charging voltage inside the medium based on the electron flux reaching the medium surface obtained by integration, and calculate the charging voltage at time t+1 based on the charging voltage at time t and the flux of high-energy electrons injected into the medium. By analogy, the continuous change process of the charging voltage deep inside the satellite medium is obtained, thereby realizing continuous monitoring and evaluation of the deep charging risk of the satellite medium, and having strong practicality.

[0106] The relative deviation between the calculated value of the charging voltage and the measured value of the charging voltage according to the above method of the present invention is 10.9%, which is highly practical under the current existing conditions.

[0107] It can be seen that the satellite internal medium deep charging monitoring method described in the present invention can more effectively evaluate and continuously monitor the deep charging risks of satellite internal media compared with related technologies. The evaluation results are more accurate, the evaluation efficiency is higher, the risk monitoring is more convenient, and the user experience is improved.

[0108] In a preferred embodiment, the following steps are also included:

[0109] If the high-energy electron monitoring data and / or high-energy electron model operation process is continuous, the calculation is performed continuously and the deep charging file is generated regularly;

[0110] If the high-energy electron spectrum data is interrupted, the calculation of the charging voltage is interrupted.

[0111] Specifically, when the high-energy electron spectrum data is interrupted to generate discontinuous data, the calculation result is inaccurate. Therefore, interrupting the calculation of the charging voltage can avoid errors in the calculation result and improve the accuracy of risk assessment and monitoring.

[0112] Preferably, the method further comprises the following step: when the calculation of the charging voltage is interrupted, generating and deriving a deep charging file.

[0113] In a preferred embodiment, the following steps are also included: generating files regularly and pushing the files out of deep charging files.

[0114] The above description is only a preferred embodiment of the present invention, and does not limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made by using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A method for assessing and monitoring the risk of deep charging of satellite internal media, characterized in that: include: Obtain the surface electron fluxes F1 and F2 of the two energy channels of the internal medium of the satellite to be tested, and respectively compare the surface electron fluxes F1 and F2 with the commonly used standard energy value E1 = 0.8M e V and E2 = 2M e Substitute V into the high-energy electron differential energy spectrum formula: F = AE B , the high energy electron spectrum parameters A and B are calculated; Divide 24 hours into a number of predetermined moments on average, and use a satellite high-energy electron detector to obtain the energies E3 and E4 of high-energy electrons of two different energy channels incident on the internal medium of the satellite at the predetermined moments; The shielding thickness r0 of the satellite internal medium is obtained according to the statistical relationship between the maximum range L of the electron and the electron energy E and the statistical relationship between the critical thickness a of the protective layer at which the electron flux attenuates and the electron energy E: a=0.283E, and the lower limit of energy E of electron deposition in the internal medium under the condition of shielding thickness r0 is calculated. min The critical thickness a of the protective layer at which the electron flux attenuates, where r0, L and a are in g / cm 2 , the unit of E is M e V; Obtain the shielding distance x between the inspection layer inside the circuit board and the outer surface of the satellite, according to the energy upper limit condition inequality: x <L(E max ) and the energy lower limit inequality: x≥L(E min )-a(E min ), the upper limit of the energy for deposition E is calculated max , where x is in g / cm 2 , L(E max )、L(E min ) are the maximum range of electrons when the electron deposition energy reaches the upper and lower limits, respectively, a(E min ) is the critical thickness when the electron deposition energy reaches the lower limit; Obtain the circuit board area S of the satellite and the resistance R of the internal medium, and convert the circuit board area S, the resistance R, and the energy upper limit E max and the energy lower limit E min Substitute the following formula to calculate the voltage value U of the predetermined level: Divide the predetermined voltage range into four risk levels of no risk, low risk, medium risk and high risk, evaluate the risk level according to the voltage value, and generate chart data of the voltage value obtained at each predetermined time and the evaluated risk level; The method of obtaining the energies E3 and E4 of the high-energy electrons of two different energy channels incident on the internal medium of the satellite at the predetermined time by using the satellite high-energy electron detector comprises: Dividing the energy spectrum of the high-energy electrons into two energy intervals with different energy values ​​according to the detection energy of the satellite high-energy electron detector; The median value of the electron energy in each energy interval is used as the energy E3 and E4 of the high-energy electrons of the energy channel; The shielding thickness r0 of the satellite internal medium is obtained according to the statistical relationship between the maximum range L of the electron and the electron energy E and the statistical relationship between the critical thickness a of the protective layer at which the electron flux attenuates and the electron energy E: a=0.283E, and the lower limit of energy E of electron deposition in the internal medium under the condition of shielding thickness r0 is calculated. min The critical thickness a of the protective layer where the electron flux attenuates includes: Calculate the electron flux change rate ratio of each energy channel high-energy electrons passing through the satellite protection layer with a thickness of r0: The unit of r0 is g / cm 2 ; The shielding thickness r0 of the satellite internal medium is obtained according to the statistical relationship between the maximum range L of the electron and the electron energy E and the statistical relationship between the critical thickness a of the protective layer at which the electron flux attenuates and the electron energy E: a=0.283E, and the lower limit of energy E of electron deposition in the internal medium under the condition of shielding thickness r0 is calculated. min and the critical thickness a of the protective layer at which the electron flux attenuates, further comprising the following steps: The electron flux f1 of each energy channel is calculated by the surface electron flux F1, F2 and the electron flux change rate ratio: f1 = F1 × ratio and f2 = F2 × ratio; The total electron flux F reaching the surface of the satellite's internal medium is calculated as: F = f1 + f2; Substitute the total electron flux F into the high-energy electron differential energy spectrum formula: F = AE B , calculate the corrected electron energy E′, and then use the electron energy E′ to calculate the voltage value.

2. The method for assessing and monitoring the risk of deep charging of satellite internal medium as claimed in claim 1, characterized in that: It also includes continuously monitoring the charging voltage of the satellite's internal medium.

3. The method for assessing and monitoring the risk of deep-layer charging of satellite internal medium as claimed in claim 2, characterized in that: Continuously monitoring the charging voltage of the satellite internal medium comprises the following steps: Obtaining an initial voltage U1 of the satellite internal medium; Calculate the voltage change du of the satellite internal medium, du = (SFQ e -U t / R) / C; Obtain the charging voltage U of the satellite internal medium at the observation time t t ; According to the charging voltage U at the observation time t t Calculate the charging voltage U of the satellite internal medium at the next observation time t+1 t+1 , U t+1 =U t +du; Where S is the detection area of ​​the satellite's internal medium, in cm 2 ;Q e is the electron charge, C is the capacitance of the satellite's internal medium; F t is the total electron flux at the above observation time t.

4. The method for assessing and monitoring the risk of deep-layer charging of satellite internal medium as claimed in claim 3, characterized in that: The following steps are also included: If the high-energy electron monitoring data and / or high-energy electron model operation process is continuous, the calculation is performed continuously and the deep charging file is generated regularly; If the high-energy electron spectrum data is interrupted, the calculation of the charging voltage is interrupted.

5. The method for assessing and monitoring the risk of deep-layer charging of satellite internal medium as claimed in claim 4, characterized in that: The following steps are also included: When the calculation of the charging voltage is interrupted, a deep charging file is generated and pushed out.

6. The method for assessing and monitoring the risk of deep-layer charging of satellite internal medium as claimed in claim 5, characterized in that: The following steps are also included: Generate files regularly and push said files out to the deep charge files.

Images