Space arc fault detection method, system and storage medium

Abstract

The present invention discloses a method, system and medium for detecting spatial arc faults. The method includes: obtaining the output voltage V of the solar array in the system to be measured SA , and comparing V SA with a preset comparator threshold Thsa; if V SA is greater than the comparator threshold Thsa, then read the value of the current differential signal V CT on the cable of the system to be measured within a preset time period after triggering the arc; perform time-domain feature analysis and frequency-spectrum feature analysis on the value of the current differential signal V CT on the cable of the system to be measured within a preset time period after triggering the arc to obtain time-frequency domain feature values; according to the current working mode of the shunt regulator of the system to be measured, compare the time-frequency domain feature values with the time-frequency domain feature thresholds corresponding to the working modes in the normal working stage of the system to be measured preset, and determine whether an arc fault occurs in the system to be measured. Compared with the prior art, the present invention can detect and eliminate arc faults in time to ensure the safe operation of the system.

Description

Technical Field

[0001] The present invention relates to the field of space arc fault detection and arc extinguishing technology, and in particular to a space arc fault detection method, system and storage medium. Background Art

[0002] Components in the space power system that directly face the space plasma environment are easily damaged by the charging and discharging effects, increasing the risk of vacuum arc discharge and threatening the safety of the space power system.

[0003] At present, the main arc fault detection methods include remote monitoring methods based on electromagnetic and thermal radiation signals; time domain and frequency domain analysis methods based on current and voltage signals; detection methods based on intelligent learning algorithms, etc. Remote detection is easily interfered by space factors; single time domain or frequency domain feature detection has the disadvantages of low detection rate and high false detection rate; and complex algorithms such as artificial intelligence have problems such as large amount of calculation, long detection time and uninterruptibility, making it difficult to use in space practice. Space arc hazards are high risk and difficult to predict and control. Their destructiveness depends on the duration. In addition, the space power supply operation mode is complex, which interferes with detection. Therefore, more reliable power supply detection and arc extinguishing technology are needed to detect and eliminate arc faults in time to ensure the safe operation of the system. Summary of the invention

[0004] The main purpose of the present invention is to provide a space arc fault detection method, system and storage medium, aiming to detect and eliminate arc faults in a timely manner and ensure the safe operation of the system.

[0005] To achieve the above object, the present invention provides a space arc fault detection method, the method comprising the following steps:

[0006] Step S10, obtaining the output voltage V of the solar cell array in the system to be tested SA and the output voltage V SA Compared with the preset comparator threshold Thsa;

[0007] Step S20: If the output voltage V SA If the current differential signal V on the cable of the system to be tested is greater than the comparator threshold Thsa, the current differential signal V on the cable of the system to be tested within a preset time period after the arc is triggered is read. CT value;

[0008] Step S30, the current differential signal V on the cable of the system to be tested within a preset time period after the arc is triggered CT The time domain characteristic analysis and spectrum characteristic analysis are performed on the values ​​to obtain the time-frequency domain characteristic values;

[0009] Step S40, according to the current working mode of the shunt regulator of the system under test, the time-frequency domain characteristic value is compared with the preset time-frequency domain characteristic threshold value under the working mode corresponding to the normal working stage of the system under test, to determine whether an arc fault occurs in the system under test, wherein the working mode includes a regulation mode, a bus power supply mode and a shunt mode.

[0010] A further technical solution of the present invention is that, in step S40, according to the current working mode of the shunt regulator of the system to be tested, the time-frequency domain characteristic value is compared with a preset time-frequency domain characteristic threshold value of the shunt regulator corresponding to the working mode in the normal working stage of the system to be tested, and the step of determining whether an arc fault occurs in the system to be tested comprises:

[0011] Step S401, calculating the current differential signal V on the cable of the system to be tested within a first preset time period after the arc is triggered CT The variance of the value σ 2 and peak-to-peak V p-p , and the FFT spectrum integral values ​​W1 to Wn of n equally spaced frequency bands within the arc spectrum distribution range;

[0012] Step S402, determining the current differential signal V on the cable of the system to be tested within a preset time period after the arc is triggered according to the current working mode of the shunt regulator of the system to be tested CT The variance of the value σ 2 and peak-to-peak V p-p ;

[0013] Step S403, if the preset conditions are met, determine whether 80% or more of the FFT spectrum integral values ​​W1 to Wn of the n equally spaced frequency bands within the arc spectrum distribution range meet a preset upper threshold value of the FFT spectrum integral value of the shunt regulator in the corresponding working mode during the normal working stage of the system under test, and are greater than a lower threshold value;

[0014] If yes, it is determined that an arc fault occurs in the system to be tested;

[0015] If not, the process returns to step S10.

[0016] A further technical solution of the present invention is that the preset condition in step S402 is:

[0017] If the current working mode of the shunt regulator of the system to be tested is the shunt mode or the bus power supply mode, the current differential signal V on the cable of the system to be tested within the preset time period after the arc is triggered CT The variance of the value σ 2is greater than a preset lower limit threshold value Thal of the variance of the shunt regulator in the shunt mode or bus power supply mode during the normal working phase of the system under test, and the current differential signal V on the cable of the system under test within a preset time period after the arc is triggered CT Peak-to-peak value V p-p is greater than a preset peak-to-peak value lower limit threshold Thpl of the shunt regulator in the shunt mode or the bus power supply mode during the normal working phase of the system to be tested;

[0018] If the current operating mode of the shunt regulator of the system to be tested is the regulation mode, the variance σ of the current differential signal VCT value on the cable of the system to be tested within the preset time period after the arc is triggered is 2 is smaller than a preset upper threshold value Thah of the variance of the shunt regulator in the regulation mode during the normal working phase of the system under test, and the current differential signal V on the cable of the system under test within a preset time period after the arc is triggered CT Peak-to-peak value V p-p is smaller than a preset peak-to-peak value upper limit threshold Thph of the shunt regulator in the regulation mode during the normal operation phase of the system to be tested.

[0019] A further technical solution of the present invention is that the first preset time period is 2ms.

[0020] A further technical solution of the present invention is that, in step S10, the output voltage V of the solar cell array in the system to be tested is obtained. SA and the output voltage V SA The step of comparing with the preset comparator threshold Thsa includes:

[0021] The solar array output voltage V SA ;

[0022] The output voltage V of the solar cell array during the normal working stage of the system to be tested is determined in a preset manner. SA Determine the operating mode of the shunt regulator of the system under test.

[0023] A further technical solution of the present invention is that the output voltage V of the solar cell array during the normal working stage of the system to be tested is preset in a preset manner. SA The step of determining the working mode of the shunt regulator of the system to be tested comprises:

[0024] Calculate the output voltage V of the solar array within 5ms SA The average value Vavg and peak-to-peak value Vpp;

[0025] If the peak-to-peak value Vpp is greater than half of the bus voltage Vbus of the system to be tested, it is determined that the working mode of the shunt regulator of the system to be tested is a regulation mode;

[0026] If the peak-to-peak value Vpp is not greater than half of the bus voltage Vbus of the system to be tested, and the solar array output voltage V SA If the average value Vavg of the measured value is greater than half of the bus voltage Vbus of the system to be tested, it is determined that the working mode of the shunt regulator of the system to be tested is the bus power supply mode;

[0027] If the peak-to-peak value Vpp is not greater than half of the bus voltage Vbus of the system to be tested, and the solar array output voltage V SA If the average value Vavg of the bus voltage Vbus of the system to be tested is not greater than half of the bus voltage Vbus of the system to be tested, it is determined that the operating mode of the shunt regulator of the system to be tested is the shunt mode.

[0028] A further technical solution of the present invention is that, in step S10, the output voltage V of the solar cell array in the system to be tested is obtained. SA and the output voltage V SA The step of comparing with the preset comparator threshold value Thsa also includes:

[0029] Read the current differential signal V on the cable during the normal working phase of the system under test within 2ms CT value;

[0030] The current differential signal V CT The value is band-pass filtered and the processed current differential signal V CT The time domain and frequency domain calculations are performed on the values, and the arc judgment threshold corresponding to the working mode is preset, wherein the time domain analysis characteristic parameters at least include variance and peak-to-peak value, the frequency domain analysis characteristic parameters are the FFT spectrum integral values ​​W1 to Wn of n equally spaced frequency bands within the arc spectrum distribution range, and the arc judgment threshold includes the variance lower limit threshold Thal, the peak-to-peak lower limit threshold Thpl, the upper limit threshold Thfh of the FFT spectrum integral value, and the lower limit threshold Thfl of the FFT spectrum integral value in the shunt mode and the bus power supply mode, and the variance upper limit threshold Thah, the peak-to-peak upper limit threshold Thph, the upper limit threshold Thfh of the FFT spectrum integral value, and the lower limit threshold Thfl of the FFT spectrum integral value in the regulation mode.

[0031] A further technical solution of the present invention is that, in step S40, according to the current working mode of the shunt regulator of the system to be tested, the time-frequency domain characteristic value is compared with a preset time-frequency domain characteristic threshold value in the corresponding working mode of the normal working stage of the system to be tested, and after the step of determining whether an arc fault occurs in the system to be tested, the step further includes:

[0032] If an arc fault occurs in the system to be tested, arc extinguishing processing is performed on the system to be tested.

[0033] To achieve the above objectives, the present invention also proposes a space arc fault detection system, which includes a memory, a processor, and a space arc fault detection program stored on the processor, and the space arc fault detection program executes the steps of the method described above when run by the processor.

[0034] To achieve the above objective, the present invention further proposes a computer-readable storage medium, wherein the computer-readable storage medium stores a space arc fault detection program, and the space arc fault detection program executes the steps of the above method when executed by a processor.

[0035] The beneficial effects of the space arc fault detection method, system and storage medium of the present invention are:

[0036] 1: Perform pre-detection during the normal working stage of the system to be tested to obtain the system's real-time working state parameters and timely frequency domain characteristic values, so as to set the dynamic threshold, make the detection applicable to power supply systems with a wider range of power levels, and further improve the detection accuracy and anti-interference ability of the detection device;

[0037] 2: The spectrum energy of signals in different frequency bands in the selected arc characteristic frequency domain is integrated. The spectrum energy value obtained by integration is more reliable than that of a single frequency. By comparing the integrated value of signals in multiple frequency bands with the set threshold, the reliability of detection can be improved and the influence of a fixed interference frequency can be eliminated;

[0038] 3: Combining time domain signal parameters and frequency domain signal parameters, and comprehensively comparing multiple characteristic parameters can effectively eliminate the interference of working mode conversion on the detection results, effectively extract arc characteristics, and thus improve the arc fault detection rate, reduce the false detection rate, and improve the reliability of the arc fault detection device;

[0039] 4: The arc detection method combining time domain and frequency domain is also applicable to arc faults occurring in many other electrical systems, such as inverters, relays, sockets, power supplies, etc.;

[0040] 5: The spatial arc fault detection method proposed in this invention is also applicable to other photovoltaic systems. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0042] Figure 1 It is a flow chart of a preferred embodiment of the space arc fault detection method of the present invention;

[0043] Figure 2 It is a hardware framework diagram for the operation of the space arc fault detection method of the present invention.

[0044] Figure 3 It is a schematic diagram of the overall process of the space arc fault detection method of the present invention.

[0045] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0046] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0047] Please refer to Figure 1 The present invention proposes a space arc fault detection method. A preferred embodiment of the space arc fault detection method of the present invention comprises the following steps:

[0048] Step S10, obtaining the output voltage V of the solar cell array in the system to be tested SA and the output voltage V SA Compared with the preset comparator threshold Thsa.

[0049] Step S20: If the output voltage V SA If the current differential signal V on the cable of the system to be tested is greater than the comparator threshold Thsa, the current differential signal V on the cable of the system to be tested within a preset time period after the arc is triggered is read. CT value.

[0050] Step S30, the current differential signal V on the cable of the system to be tested within a preset time period after the arc is triggered CT The time domain characteristic analysis and spectrum characteristic analysis are performed on the values ​​to obtain the time-frequency domain characteristic values.

[0051] Step S40, according to the current working mode of the shunt regulator of the system under test, the time-frequency domain characteristic value is compared with the preset time-frequency domain characteristic threshold value under the working mode corresponding to the normal working stage of the system under test, to determine whether an arc fault occurs in the system under test, wherein the working mode includes a regulation mode, a bus power supply mode and a shunt mode.

[0052] Wherein, the step S40, according to the current working mode of the shunt regulator of the system to be tested, compares the time-frequency domain characteristic value with the preset time-frequency domain characteristic threshold value of the shunt regulator corresponding to the working mode in the normal working stage of the system to be tested, and determines whether an arc fault occurs in the system to be tested, comprises:

[0053] Step S401, calculating the current differential signal V on the cable of the system to be tested within a first preset time period after the arc is triggered CT The variance of the value σ 2 and peak-to-peak V p-p , and the FFT spectrum integral values ​​W1 to Wn of n equally spaced frequency bands within the arc spectrum distribution range.

[0054] Step S402, determining the current differential signal V on the cable of the system to be tested within a preset time period after the arc is triggered according to the current working mode of the shunt regulator of the system to be tested CT The variance of the value σ 2 and peak-to-peak V p-p .

[0055] Step S403, if the preset conditions are met, determine whether 80% or more of the FFT spectrum integral values ​​W1 to Wn of the n equally spaced frequency bands within the arc spectrum distribution range meet the preset upper limit threshold of the FFT spectrum integral value of the shunt regulator in the corresponding working mode during the normal working stage of the system under test, and are greater than the lower limit threshold.

[0056] If so, it is determined that an arc fault occurs in the system to be tested.

[0057] If not, the process returns to step S10.

[0058] The preset conditions in step S402 are:

[0059] If the current working mode of the shunt regulator of the system to be tested is the shunt mode or the bus power supply mode, the current differential signal V on the cable of the system to be tested within the preset time period after the arc is triggered CT The variance of the value σ 2is greater than a preset lower limit threshold value Thal of the variance of the shunt regulator in the shunt mode or bus power supply mode during the normal working phase of the system under test, and the current differential signal V on the cable of the system under test within a preset time period after the arc is triggered CT Peak-to-peak value V p-p Greater than a preset peak-to-peak value lower limit threshold Thpl of the shunt regulator in the shunt mode or the bus power supply mode during the normal operation phase of the system to be tested.

[0060] If the current operating mode of the shunt regulator of the system to be tested is the regulation mode, the variance σ of the current differential signal VCT value on the cable of the system to be tested within the preset time period after the arc is triggered is 2 is smaller than a preset upper threshold value Thah of the variance of the shunt regulator in the regulation mode during the normal working phase of the system under test, and the current differential signal V on the cable of the system under test within a preset time period after the arc is triggered CT Peak-to-peak value V p-p is smaller than a preset peak-to-peak value upper limit threshold Thph of the shunt regulator in the regulation mode during the normal operation phase of the system to be tested.

[0061] In this embodiment, the first preset time period is 2 ms.

[0062] In this embodiment, the step S10 is to obtain the output voltage V of the solar cell array in the system to be tested. SA and the output voltage V SA The step of comparing with the preset comparator threshold Thsa includes:

[0063] The solar array output voltage V SA .

[0064] The output voltage V of the solar cell array during the normal working stage of the system to be tested is determined in a preset manner. SA Determine the operating mode of the shunt regulator of the system under test.

[0065] In this embodiment, the output voltage V of the solar cell array during the normal working stage of the system to be tested is determined in a preset manner. SA The step of determining the working mode of the shunt regulator of the system to be tested includes:

[0066] Calculate the output voltage V of the solar array within 5ms SA The average value Vavg and peak-to-peak value Vpp.

[0067] If the peak-to-peak value Vpp is greater than half of the bus voltage Vbus of the system under test, it is determined that the operating mode of the shunt regulator of the system under test is the regulation mode.

[0068] If the peak-to-peak value Vpp is not greater than half of the bus voltage Vbus of the system to be tested, and the solar array output voltage V SA If the average value Vavg of the measured value is greater than half of the bus voltage Vbus of the measured system, it is determined that the working mode of the shunt regulator of the measured system is the bus power supply mode.

[0069] If the peak-to-peak value Vpp is not greater than half of the bus voltage Vbus of the system to be tested, and the solar array output voltage V SA If the average value Vavg of the bus voltage Vbus of the system to be tested is not greater than half of the bus voltage Vbus of the system to be tested, it is determined that the operating mode of the shunt regulator of the system to be tested is the shunt mode.

[0070] In this embodiment, the step S10 is to obtain the output voltage V of the solar cell array in the system to be tested. SA and the output voltage V SA The step of comparing with the preset comparator threshold value Thsa also includes:

[0071] Read the current differential signal V on the cable during the normal working phase of the system under test within 2ms CT value.

[0072] The current differential signal V CT The value is band-pass filtered and the processed current differential signal V CT The time domain and frequency domain values ​​are calculated, and the arc judgment threshold corresponding to the working mode is preset (that is, the time-frequency domain characteristic threshold), wherein the time domain analysis characteristic parameters at least include variance and peak-to-peak value, and the frequency domain analysis characteristic parameters are the FFT spectrum integral values ​​W1 to Wn of n equally spaced frequency bands within the arc spectrum distribution range, and the arc judgment threshold includes the variance lower limit threshold Thal, the peak-to-peak value lower limit threshold Thpl, the upper limit threshold Thfh of the FFT spectrum integral value, and the lower limit threshold Thfl of the FFT spectrum integral value in the shunt mode and the bus power supply mode, and the variance upper limit threshold Thah, the peak-to-peak value upper limit threshold Thph, the upper limit threshold Thfh of the FFT spectrum integral value, and the lower limit threshold Thfl of the FFT spectrum integral value in the regulation mode.

[0073] In this embodiment, the step S40, according to the current working mode of the shunt regulator of the system to be tested, compares the time-frequency domain characteristic value with the preset time-frequency domain characteristic threshold value in the working mode corresponding to the normal working stage of the system to be tested, and determines whether an arc fault occurs in the system to be tested, further includes:

[0074] If an arc fault occurs in the system to be tested, arc extinguishing processing is performed on the system to be tested.

[0075] The following combination Figure 2 and Figure 3 The space arc fault detection method of the present invention is further elaborated in detail.

[0076] like Figure 2 As shown, Figure 2 This is a hardware framework diagram for the space arc fault detection method of the present invention. The hardware framework for the space arc fault detection method of the present invention includes a system to be tested, a signal sampling link, a filtering link, a data processing link, a logic judgment link, and an arc extinguishing link. Among them, the system to be tested is a space power supply system, including a solar cell array, components that may generate space arc discharge, a shunt regulator, etc.; the data processing link includes two parts: pre-detection and arc characteristic analysis; the arc extinguishing link includes a power switch and an impedance.

[0077] The signal sampling link is used to detect the output voltage V of the solar cell array in the system to be tested. SA and the current differential signal V on the cable CT The data processing stage first passes through V SA The working modes of the shunt regulator are determined to be regulation mode, bus power supply mode and shunt mode. CT Perform time domain and frequency domain calculations and preset the arc judgment threshold for the corresponding working mode. The time domain analysis characteristic parameters mainly include variance, peak-to-peak value, etc.; while the frequency domain analysis characteristic parameters are the FFT spectrum integral of equally spaced frequency bands within the arc spectrum distribution range (generally 10kHz-100kHz). After the data processing link is completed, wait for the arc fault to cause V SA rises, thus triggering the arc characteristic analysis link through the comparator circuit, and judging the arc fault after the triggering V CT The data is analyzed in the time and frequency domains, and the corresponding eigenvalues ​​are calculated. In the logic judgment link, the eigenvalues ​​obtained in the arc characteristic analysis link are compared with the thresholds pre-set in the pre-detection link. The interference caused by the conversion of the working mode of the shunt regulator is first eliminated by the time domain eigenvalues, and then the frequency domain eigenvalues ​​are used to finally determine whether an arc occurs in the system to be tested. The device of the present invention sets the threshold of each detection parameter according to the configuration parameters of the electrical system and the safety level of the arc fault. If an arc is detected in the system to be tested, the arc extinguishing link is started to extinguish the arc in the system to be tested, so as to ensure the safe and reliable operation of the system and avoid damage to the system caused by the arc fault. The arc extinguishing method is to drive the power switch K from position 1 to position 2, connect the impedance Zcut to the line, and move the working point of the solar array to the open circuit voltage working point, so that the output current is reduced to 0 and the arc is extinguished.

[0078] The present invention takes into account the complexity of the working modes of the space power supply system, and the mutual conversion between the three working modes will cause greater interference to the judgment results of a single time domain or frequency domain, resulting in a higher probability of misjudgment. Therefore, the present invention combines the two, pre-determines the working mode during the normal working stage of the system to be tested, and sets the dynamic thresholds in the time and frequency domains according to the characteristic parameters of the actual operation. In the arc characteristic analysis link, the interference caused by the conversion of the working mode is first eliminated through the time domain characteristic parameters, and then the frequency domain is used to further determine whether an arc fault has occurred. When processing the frequency domain signal, the present invention selects the spectrum energy of different frequency bands for integration, and comprehensively compares multiple integration results to reduce the influence of a fixed interference frequency in the system. The present invention combines multiple parameters of time domain and frequency domain signals at the same time, thereby improving the reliability of the arc fault detection device.

[0079] Please refer to Figure 3 , the implementation process of the space arc fault detection method of the present invention is as follows:

[0080] Step 1: The output voltage V of the solar array in the system under test SA and the cable current differential signal V CT Conduct real-time sampling;

[0081] Step 2: Detect the current differential signal V CT Perform bandpass filtering;

[0082] Step 3: Perform a pre-test on the system under test during its normal working phase;

[0083] Step 31: Use the voltage data V collected during normal operation SA Determine the current operating mode of the shunt regulator;

[0084] Step 32: Use the filtered current differential data V CT Calculate the time-frequency domain characteristic values ​​under the corresponding working mode, and set the arc determination dynamic threshold value of each characteristic parameter on this basis;

[0085] Step 4: If the real-time solar array output voltage V SA When it rises and reaches the comparator threshold Thsa, the arc characteristic analysis link is triggered.

[0086] Step 5: Calculate the time-frequency domain characteristic values ​​of the data after the trigger arc characteristic analysis link.

[0087] Step 6: Compare the characteristic value calculated in the previous step with the preset threshold to determine whether an arc fault occurs in the system.

[0088] Step 7: According to the judgment result of the arc fault, if an arc fault occurs in the detection system, the arc extinguishing link is started to extinguish the arc in the detection system to protect the system under test.

[0089] The beneficial effects of the space arc fault detection method of the present invention are:

[0090] 1: Perform pre-detection during the normal working stage of the system to be tested to obtain the system's real-time working state parameters and timely frequency domain characteristic values, so as to set the dynamic threshold, make the detection applicable to power supply systems with a wider range of power levels, and further improve the detection accuracy and anti-interference ability of the detection device;

[0091] 2: The spectrum energy of signals in different frequency bands in the selected arc characteristic frequency domain is integrated. The spectrum energy value obtained by integration is more reliable than that of a single frequency. By comparing the integrated value of signals in multiple frequency bands with the set threshold, the reliability of detection can be improved and the influence of a fixed interference frequency can be eliminated;

[0092] 3: Combining time domain signal parameters and frequency domain signal parameters, and comprehensively comparing multiple characteristic parameters can effectively eliminate the interference of working mode conversion on the detection results, effectively extract arc characteristics, and thus improve the arc fault detection rate, reduce the false detection rate, and improve the reliability of the arc fault detection device;

[0093] 4: The arc detection method combining time domain and frequency domain is also applicable to arc faults occurring in many other electrical systems, such as inverters, relays, sockets, power supplies, etc.;

[0094] 5: The spatial arc fault detection method proposed in this invention is also applicable to other photovoltaic systems.

[0095] To achieve the above objectives, the present invention also proposes a space arc fault detection system, which includes a memory, a processor, and a space arc fault detection program stored on the processor. When the space arc fault detection program is run by the processor, the steps of the method described in the above embodiment are executed, which will not be repeated here.

[0096] To achieve the above objectives, the present invention further proposes a computer-readable storage medium, which stores a space arc fault detection program. When the space arc fault detection program is executed by a processor, the steps of the method described in the above embodiment are executed, which will not be repeated here.

[0097] The above description is only a preferred embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A space arc fault detection method, characterized in that: The method comprises the following steps: Step S10, obtaining the output voltage V of the solar cell array in the system to be tested SA and the output voltage V SA Compared with the preset comparator threshold Thsa; Step S20: If the output voltage V SA If the current differential signal V on the cable of the system to be tested is greater than the comparator threshold Thsa, the current differential signal V on the cable of the system to be tested within a preset time period after the arc is triggered is read. CT value; Step S30, the current differential signal V on the cable of the system to be tested within a preset time period after the arc is triggered CT The time domain characteristic analysis and spectrum characteristic analysis are performed on the values ​​to obtain the time-frequency domain characteristic values; Step S40, according to the current working mode of the shunt regulator of the system to be tested, comparing the time-frequency domain characteristic value with a preset time-frequency domain characteristic threshold value in a corresponding working mode during the normal working phase of the system to be tested, to determine whether an arc fault occurs in the system to be tested, wherein the working mode includes a regulation mode, a bus power supply mode and a shunt mode; The step S40, according to the current working mode of the shunt regulator of the system to be tested, compares the time-frequency domain characteristic value with the preset time-frequency domain characteristic threshold value of the shunt regulator corresponding to the working mode in the normal working stage of the system to be tested, and determines whether an arc fault occurs in the system to be tested, comprises: Step S401, calculating the current differential signal V on the cable of the system to be tested within a first preset time period after the arc is triggered CT The variance of the value σ 2 and peak-to-peak V p-p , and the FFT spectrum integral values ​​W1 to Wn of n equally spaced frequency bands within the arc spectrum distribution range; Step S402, determining the current differential signal V on the cable of the system to be tested within a preset time period after the arc is triggered according to the current working mode of the shunt regulator of the system to be tested CT The variance of the value σ 2 and peak-to-peak V p-p ; Step S403, if the preset conditions are met, determine whether 80% or more of the FFT spectrum integral values ​​W1 to Wn of the n equally spaced frequency bands within the arc spectrum distribution range meet a preset upper threshold value of the FFT spectrum integral value of the shunt regulator in the corresponding working mode during the normal working stage of the system under test, and are greater than a lower threshold value; If yes, it is determined that an arc fault occurs in the system to be tested; If not, the process returns to step S10.

2. The space arc fault detection method according to claim 1, characterized in that: The preset conditions in step S402 are: If the current working mode of the shunt regulator of the system to be tested is the shunt mode or the bus power supply mode, the current differential signal V on the cable of the system to be tested within the preset time period after the arc is triggered CT The variance of the value σ 2 is greater than a preset lower limit threshold value Thal of the variance of the shunt regulator in the shunt mode or bus power supply mode during the normal working phase of the system under test, and the current differential signal V on the cable of the system under test within a preset time period after the arc is triggered CT Peak-to-peak value V p-p is greater than a preset peak-to-peak value lower limit threshold Thpl of the shunt regulator in the shunt mode or the bus power supply mode during the normal working phase of the system to be tested; If the current operating mode of the shunt regulator of the system to be tested is the regulation mode, the variance σ of the current differential signal VCT value on the cable of the system to be tested within the preset time period after the arc is triggered is 2 is smaller than a preset upper threshold value Thah of the variance of the shunt regulator in the regulation mode during the normal working phase of the system under test, and the current differential signal V on the cable of the system under test within a preset time period after the arc is triggered CT Peak-to-peak value V p-p is smaller than a preset peak-to-peak value upper limit threshold Thph of the shunt regulator in the regulation mode during the normal operation phase of the system to be tested.

3. The space arc fault detection method according to claim 1, characterized in that: The first preset time period is 2 ms.

4. The space arc fault detection method according to claim 1, characterized in that: The step S10 is to obtain the output voltage V of the solar cell array in the system to be tested. SA and the output voltage V SA The step of comparing with the preset comparator threshold Thsa includes: The solar array output voltage V SA ; The output voltage V of the solar cell array during the normal working stage of the system to be tested is determined in a preset manner. SA Determine the operating mode of the shunt regulator of the system under test.

5. The method for detecting space arc faults according to claim 4, characterized in that: The output voltage V of the solar cell array during the normal working stage of the system to be tested is determined in a preset manner. SA The step of determining the working mode of the shunt regulator of the system to be tested comprises: Calculate the output voltage V of the solar array within 5ms SA The average value Vavg and peak-to-peak value Vpp; If the peak-to-peak value Vpp is greater than half of the bus voltage Vbus of the system to be tested, it is determined that the working mode of the shunt regulator of the system to be tested is a regulation mode; If the peak-to-peak value Vpp is not greater than half of the bus voltage Vbus of the system to be tested, and the solar array output voltage V SA If the average value Vavg of the measured value is greater than half of the bus voltage Vbus of the system to be tested, it is determined that the working mode of the shunt regulator of the system to be tested is the bus power supply mode; If the peak-to-peak value Vpp is not greater than half of the bus voltage Vbus of the system to be tested, and the solar array output voltage V SA If the average value Vavg of the bus voltage Vbus of the system to be tested is not greater than half of the bus voltage Vbus of the system to be tested, it is determined that the operating mode of the shunt regulator of the system to be tested is the shunt mode.

6. The method for detecting space arc faults according to claim 5, characterized in that: The step S10 is to obtain the output voltage V of the solar cell array in the system to be tested. SA and the output voltage V SA The step of comparing with the preset comparator threshold value Thsa also includes: Read the current differential signal V on the cable during the normal working phase of the system under test within 2ms CT value; The current differential signal V CT The value is band-pass filtered and the processed current differential signal V CT The time domain and frequency domain calculations are performed on the values, and the arc judgment threshold corresponding to the working mode is preset, wherein the time domain analysis characteristic parameters at least include variance and peak-to-peak value, the frequency domain analysis characteristic parameters are the FFT spectrum integral values ​​W1 to Wn of n equally spaced frequency bands within the arc spectrum distribution range, and the arc judgment threshold includes the variance lower limit threshold Thal, the peak-to-peak lower limit threshold Thpl, the upper limit threshold Thfh of the FFT spectrum integral value, and the lower limit threshold Thfl of the FFT spectrum integral value in the shunt mode and the bus power supply mode, and the variance upper limit threshold Thah, the peak-to-peak upper limit threshold Thph, the upper limit threshold Thfh of the FFT spectrum integral value, and the lower limit threshold Thfl of the FFT spectrum integral value in the regulation mode.

7. The space arc fault detection method according to any one of claims 1 to 6, characterized in that: After the step S40 of comparing the time-frequency domain characteristic value with a preset time-frequency domain characteristic threshold value in a corresponding working mode in a normal working phase of the system under test according to the current working mode of the shunt regulator of the system under test, and determining whether an arc fault occurs in the system under test, the step further includes: If an arc fault occurs in the system to be tested, arc extinguishing processing is performed on the system to be tested.

8. A space arc fault detection system, characterized in that: The system comprises a memory, a processor, and a space arc fault detection program stored on the processor. When the space arc fault detection program is executed by the processor, the steps of the method according to any one of claims 1 to 7 are performed.

9. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a space arc fault detection program, and the space arc fault detection program is executed by a processor to perform the steps of the method according to any one of claims 1 to 7.

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