CN116466129A - Small-signal direct current leakage detection method and system - Google Patents
Small-signal direct current leakage detection method and system Download PDFInfo
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Abstract
The invention discloses a small-signal direct-current leakage detection method and a small-signal direct-current leakage detection system, which relate to the technical field of leakage detection, and are characterized in that firstly, alternating-current and direct-current mixed signals are collected and preprocessed; separating the alternating current mixing interference signal and the direct current leakage signal from the preprocessed data; finally, carrying out alternating current filtering quantization on the alternating current mixing interference signal to obtain an alternating current mixing interference standard signal, and carrying out direct current filtering quantization on the direct current leakage signal to obtain a direct current leakage standard signal; the scheme realizes the acquisition of alternating current-direct current mixed signals based on a fluxgate technology, then respectively extracts the tested alternating current-direct current signals by utilizing a digital filtering technology, and finally converts the extracted direct current pulse width signals into analog voltage signals through a DAC (digital-to-analog converter) conversion circuit to output the analog voltage signals, thereby realizing the leakage detection of mA-stage direct current small signals.
Description
Technical Field
The invention relates to the technical field of leakage current detection, in particular to a small-signal direct current leakage current detection method and system.
Background
The current mA-class direct current leakage signal detection technology in the market is more, the general signal bandwidth can only be about 2kHz, when A-class alternating current harmonic interference signals exist on a signal line, the accuracy of direct current leakage detection is greatly reduced, and finally the direct current leakage detection system is misreported.
Disclosure of Invention
The technical problems to be solved by the invention are as follows: the direct current leakage current signal detection is inaccurate due to the on-site alternating current mixing current signal interference, and the signal bandwidth is limited; the invention aims to provide a small-signal direct-current leakage detection method and system, which are used for realizing alternating-current and direct-current mixing signal acquisition based on a fluxgate technology, respectively extracting tested alternating-current and direct-current signals by utilizing a digital filtering technology, and finally converting the extracted direct-current pulse width signals into analog voltage signals through a DAC (digital-to-analog converter) conversion circuit to output the analog voltage signals so as to realize mA-stage direct-current small-signal leakage detection.
The invention is realized by the following technical scheme:
the scheme provides a small-signal direct current leakage detection method, which comprises the following steps:
step one: collecting an alternating current-direct current mixing signal and preprocessing; the alternating current-direct current mixing signal is an alternating current mixing interference current signal and a direct current leakage current signal;
step two: separating the alternating current mixing interference signal and the direct current leakage signal from the preprocessed data;
step three: and carrying out alternating current filtering quantization treatment on the alternating current mixing interference signal to obtain an alternating current mixing interference standard signal, and carrying out direct current filtering quantization treatment on the direct current leakage signal to obtain a direct current leakage standard signal.
The working principle of the scheme is as follows: the direct current leakage current signal detection is inaccurate due to the on-site alternating current mixing current signal interference, and the signal bandwidth is limited; the invention aims to provide a small-signal direct-current leakage detection method and system, which are used for realizing alternating-current and direct-current mixing signal acquisition based on a fluxgate technology, respectively extracting tested alternating-current and direct-current signals by utilizing a digital filtering technology, and finally converting the extracted direct-current pulse width signals into analog voltage signals through a DAC (digital-to-analog converter) conversion circuit to output the analog voltage signals so as to realize mA-level direct-current small-signal leakage detection.
The scheme utilizes a fluxgate technology to collect and output alternating current-direct current mixed voltage signals, the alternating current-direct current mixed voltage signals are sampled at a high speed through an ADC (analog-to-digital converter) core in the CPU, the sampled raw data are subjected to spectrum leakage compensation and then enter an IIR elliptic filter for digital filtering, and then respectively enter a direct current shunt and an alternating current shunt for processing to obtain direct current leakage standard signals and alternating current mixed interference standard signals.
In order to eliminate the interference of the on-site alternating current mixing current signals and improve the detection accuracy of the direct current leakage current signals, the acquisition equipment adopts a fluxgate technology to acquire alternating current-direct current mixing signals, then a digital filtering technology is used for respectively extracting the tested alternating current-direct current signals, and finally the extracted direct current pulse width signals are converted into analog voltage signals through a DAC (digital-to-analog converter) conversion circuit to be output. And the inspector obtains the direct current leakage, namely the alternating current mixing interference according to the direct current leakage standard signal and the alternating current mixing interference standard signal.
The traditional direct current leakage detection method cannot realize detection of wider bandwidth (such as 25 kHz), and the scheme provides a new technical concept: the detection of the bandwidth above 25kHz is realized through high-speed sampling and AC/DC separation treatment, and a foundation is laid for a small-signal DC leakage detection method.
The further optimization scheme is that the acquisition of the alternating current-direct current mixing signals is realized based on a fluxgate technology. Whether leakage current exists in the circuit is sensed through an electromagnetic induction technology, a detection device is not required to be applied to a running circuit, and convenience is provided for detection work.
In a further optimized scheme, the preprocessing comprises the following steps:
high-speed sampling is carried out on the alternating current-direct current mixed signal to obtain original data;
and (3) performing spectrum leakage compensation on the original data, and inputting the compensated original data into an IIR elliptic filter for digital filtering.
The further optimization scheme is that the direct current leakage standard signal and the alternating current mixing interference standard signal are both analog voltage signals of 0-5V.
The further optimization scheme is that the system samples a high-speed CORTEX-M7 kernel CPU, and the ADC adopts a CPU internal high-speed ADC.
The further optimization scheme is that the direct current filtering quantization processing comprises the following steps:
t1, sequentially performing Sinc4 filter filtering, 1 st RC low-pass filtering, 2 nd elliptic filter filtering and 2 nd RC low-pass filtering on the direct current signal to obtain a direct current signal L; the Sinc4 filter can obtain signals required by a direct current channel under the condition of complex mixed signal input; RC low pass filtering is performed 1 st time to remove high frequency noise from the modulator output.
And T2, carrying out per unit processing on the direct current signal L to obtain a direct current leakage standard signal.
The further optimization scheme is that the filtering in the step T1 follows:
y[k]＝a×(y[k-1]-x[k])+x[k]
a is a filtered coefficient, k is a filtered position point, x k is an original value of an input signal, y k is a filtered output value, and y k-1 is a last filtered output value.
The further optimization scheme is that the alternating current filtering quantization processing comprises the following steps:
for alternating current mixing interference signalsThe fundamental wave value and the harmonic value are separated by FFT base 4 calculation processing: after FFT calculation processing, get
Wherein,,
k represents the harmonic order, N represents the number of sampling points of a periodic signal,representing the DC component of the signal, a k Representing the real part calculation formula of the radix 4-FFT complex number, b k Representing the basis 4-FFT complex imaginary calculation formula, u representing the signal phase.
Calculating an alternating current signal amplitude based on the fundamental wave value and the harmonic wave value:
and carrying out per unit processing on the amplitude of the alternating current mixing interference signal to obtain an alternating current mixing interference standard signal.
The further optimization scheme is that the alternating current mixing interference standard signal output is as follows:
PWM_I AC ＝(I AC_SAMPLE -I AC_CALIB_ZERO )*10000/(I AC_CALIB_FULL -I AC_CALIB_ZERO )
wherein:
PWM_I AC representing the output value of alternating current mixing interference current, and the resolution is one ten thousandth;
I AC_SAMPLE representing the real-time sampling per unit value of alternating current mixing interference current;
I AC_CALIB_FULL representing a positive full value calibration value of an alternating current mixing interference current signal;
I AC_CALIB_ZERO representing zero calibration value of alternating current mixing interference current signals;
the output of the direct current leakage standard signal is as follows:
PWM_I DC ＝(I DC_SAMPLE -I DC_CALIB_ZERO )*10000/(I DC_CALIB_FULL -I DC_CALIB_ZERO )
wherein:
PWM_I DC output value of DC leakage current, resolution is one ten thousandth;
I DC_SAMPLE sampling per unit value of direct current leakage current in real time;
I DC_CALIB_FULL direct current leakage current signal positive full value calibration value;
I DC_CALIB_ZERO zero calibration value of direct current leakage current signal.
The scheme also provides a small-signal direct current leakage detection system, which is used for realizing the small-signal direct current leakage detection method according to the scheme, and comprises the following steps:
the acquisition module acquires the alternating current-direct current mixing signal and performs pretreatment; the alternating current-direct current mixing signal is an alternating current mixing interference current signal and a direct current leakage current signal; the acquisition module is a fluxgate acquisition device;
the preprocessing module is used for separating alternating current mixing interference signals and direct current leakage signals from the preprocessed data;
and the detection module is used for carrying out alternating current filtering quantization processing on the alternating current mixing interference signal to obtain an alternating current mixing interference standard signal, and carrying out direct current filtering quantization processing on the direct current leakage signal to obtain a direct current leakage standard signal.
Compared with the prior art, the invention has the following advantages and beneficial effects:
the invention provides a small-signal direct-current leakage detection method and a system, which are used for realizing alternating-current and direct-current mixed signal acquisition based on a fluxgate technology, respectively extracting tested alternating-current and direct-current signals by utilizing a digital filtering technology, and finally converting the extracted direct-current pulse width signals into analog voltage signals through a DAC (digital-to-analog converter) conversion circuit to output the analog voltage signals so as to realize mA-level direct-current small-signal leakage detection; the traditional direct current leakage detection method cannot realize detection of wider bandwidth (such as 25 kHz), and the scheme provides a new technical concept: the detection of the bandwidth above 25kHz is realized through high-speed sampling and AC/DC separation treatment, and a foundation is laid for a small-signal DC leakage detection method.
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In order to more clearly illustrate the technical solutions of the exemplary embodiments of the present invention, the drawings that are needed in the examples will be briefly described below, it being understood that the following drawings only illustrate some examples of the present invention and therefore should not be considered as limiting the scope, and that other related drawings may be obtained from these drawings without inventive effort for a person skilled in the art.
In the drawings:
FIG. 1 is a schematic flow chart of a small signal DC leakage detection method;
FIG. 2 is a block diagram of the overall scheme of a small signal DC leakage detection system;
FIG. 3 is a digital filtering scheme;
FIG. 4 is a high-speed sampling scheme of a small-signal DC leakage detection system;
FIG. 5 is an analog interference signal waveform;
fig. 6 is a simulated output waveform.
Detailed Description
For the purpose of making apparent the objects, technical solutions and advantages of the present invention, the present invention will be further described in detail with reference to the following examples and the accompanying drawings, wherein the exemplary embodiments of the present invention and the descriptions thereof are for illustrating the present invention only and are not to be construed as limiting the present invention.
The direct current leakage current signal detection is inaccurate due to the on-site alternating current mixing current signal interference, and the signal bandwidth is limited; in order to eliminate the interference of the on-site alternating current mixing current signal and improve the detection accuracy of the direct current leakage current signal, the invention provides the following embodiments:
the sensor adopts a fluxgate technology to realize the acquisition of alternating current-direct current mixed signals, then utilizes a digital filtering technology to respectively extract the measured alternating current-direct current signals, and finally converts the extracted direct current pulse width signals into analog voltage signals through a DAC (digital-to-analog converter) conversion circuit to output.
Example 1
The embodiment provides a small-signal direct current leakage detection method, as shown in fig. 1, including:
step one: collecting an alternating current-direct current mixing signal and preprocessing;
step two: separating the alternating current mixing interference signal and the direct current leakage signal from the preprocessed data;
step three: and carrying out alternating current filtering quantization treatment on the alternating current mixing interference signal to obtain an alternating current mixing interference standard signal, and carrying out direct current filtering quantization treatment on the direct current leakage signal to obtain a direct current leakage standard signal.
The acquisition of the alternating current-direct current mixing signal is realized based on a fluxgate technology.
The pretreatment comprises the following steps:
high-speed sampling is carried out on the alternating current-direct current mixed signal to obtain original data;
and (3) performing spectrum leakage compensation on the original data, and inputting the compensated original data into an IIR elliptic filter for digital filtering.
The direct current leakage standard signal and the alternating current mixing interference standard signal are both analog voltage signals of 0-5V.
The system samples a high-speed CORTEX-M7 kernel CPU, and the ADC adopts a CPU internal high-speed ADC.
The DC filtering quantization process comprises the following steps:
t1, sequentially performing Sinc4 filter filtering, 1 st RC low-pass filtering, 2 nd elliptic filter filtering and 2 nd RC low-pass filtering on the direct current signal to obtain a direct current signal L;
and T2, carrying out per unit processing on the direct current signal L to obtain a direct current leakage standard signal.
The filtering in step T1 follows:
y[k]＝a×(y[k-1]-x[k])+x[k]
a is a filtered coefficient, k is a filtered position point, x k is an original value of an input signal, y k is a filtered output value, and y k-1 is a last filtered output value.
The alternating current filtering quantization process comprises the following steps:
for alternating current mixing interference signalsThe fundamental wave value and the harmonic value are separated by FFT base 4 calculation processing: after FFT calculation processing, get
Wherein,,
k represents the harmonic order, N represents the number of sampling points of a periodic signal,representing the DC component of the signal, a k Representing the real part calculation formula of the radix 4-FFT complex number, b k Representing the basis 4-FFT complex imaginary calculation formula, u representing the signal phase.
Calculating an alternating current signal amplitude based on the fundamental wave value and the harmonic wave value:
and carrying out per unit processing on the amplitude of the alternating current mixing interference signal to obtain an alternating current mixing interference standard signal.
The alternating current mixing interference standard signal output is as follows:
PWM_I AC ＝(I AC_SAMPLE -I AC_CALIB_ZERO )*10000/(I AC_CALIB_FULL -I AC_CALIB_ZERO )
wherein:
PWM_I AC the resolution ratio is one ten thousandth of the output value of alternating current mixing interference current;
I AC_SAMPLE sampling per unit value for alternating current mixing interference current in real time;
I AC_CALIB_FULL the method comprises the steps of (1) calibrating a forward full value of an alternating-current mixing interference current signal;
I AC_CALIB_ZERO zero calibration value of alternating-current mixing interference current signals;
the output of the direct current leakage standard signal is as follows:
PWM_I DC ＝(I DC_SAMPLE -I DC_CALIB_ZERO )*10000/(I DC_CALIB_FULL -I DC_CALIB_ZERO )；
wherein:
PWM_I DC DC leakage current outputValue, resolution one ten thousandth;
I DC_SAMPLE sampling per unit value of direct current leakage current in real time;
I DC_CALIB_FULL direct current leakage current signal positive full value calibration value;
I DC_CALIB_ZERO zero calibration value of direct current leakage current signal.
Firstly, collecting an alternating current-direct current mixing signal and preprocessing the alternating current-direct current mixing signal; separating the alternating current mixing interference signal and the direct current leakage signal from the preprocessed data; finally, carrying out alternating current filtering quantization on the alternating current mixing interference signal to obtain an alternating current mixing interference standard signal, and carrying out direct current filtering quantization on the direct current leakage signal to obtain a direct current leakage standard signal; the scheme realizes the acquisition of alternating current-direct current mixed signals based on a fluxgate technology, then respectively extracts the tested alternating current-direct current signals by utilizing a digital filtering technology, and finally converts the extracted direct current pulse width signals into analog voltage signals through a DAC (digital-to-analog converter) conversion circuit to output the analog voltage signals, thereby realizing the leakage detection of mA-stage direct current small signals.
Example 2
The embodiment provides a small-signal direct current leakage detection system, which is used for implementing the small-signal direct current leakage detection method described in embodiment 1, and includes:
the acquisition module is used for acquiring the alternating current-direct current mixing signals and preprocessing the alternating current-direct current mixing signals; the acquisition module is a fluxgate acquisition device;
the preprocessing module is used for separating alternating current mixing interference signals and direct current leakage signals from the preprocessed data;
and the detection module is used for carrying out alternating current filtering quantization processing on the alternating current mixing interference signal to obtain an alternating current mixing interference standard signal, and carrying out direct current filtering quantization processing on the direct current leakage signal to obtain a direct current leakage standard signal. The workflow of the small signal dc leakage detection system is shown in fig. 2. In order to eliminate the interference of on-site alternating current mixing current signals and improve the detection accuracy of direct current leakage current signals, the sensor adopts a fluxgate technology to acquire alternating current-direct current mixing signals, then a digital filtering technology is used for respectively extracting tested alternating current-direct current signals, and finally a DAC (digital-to-analog converter) conversion circuit is used for converting the extracted direct current pulse width signals into analog voltage signals to be output.
The single extraction of the alternating current-direct current mixing signals is realized by adopting a digital filtering technology, as shown in fig. 3, the output alternating current-direct current mixing voltage signals are collected by utilizing a fluxgate technology, are sampled at a high speed through an internal ADC (analog to digital converter) (> 50 kHz), the adopted original data are subjected to frequency spectrum leakage compensation, then enter an IIR elliptic filter for digital filtering, and respectively enter a direct current shunt and an alternating current shunt for processing.
The system samples the high-speed CORTEX-M7 kernel CPU, the ADC adopts the CPU internal high-speed ADC to realize 25kHz bandwidth, as shown in figure 4, the sampling frequency of the ADC is 50 x 1024=51.2 kHz based on the 16-bit high-speed AD high-speed sampling original signal (16 bit ADC:3.6 MSPS), the noise of the sampled data is reduced, each original data realizes 256 times of oversampling, and 1024 original data (alternating current mixing interference signals and direct current leakage signals) are obtained according to the sampling period of the original signal.
Direct current shunt:
after the original data (direct current signal) is subjected to IIR data filtering, the filtered data is filtered by a Sinc4 filter, a signal required by a direct current channel can be obtained under the condition of complex mixed signal input, then the data is subjected to 1 st RC low-pass filtering so as to remove high-frequency noise output by a modulator, then the data is subjected to 2 nd elliptical filter filtering, then the data is subjected to 2 nd RC low-pass filtering so as to obtain a DC signal, the obtained data is subjected to per unit processing, and finally PWM output is performed.
LPC filtering formula:
y[k]＝a×(y[k-1]-x[k])+x[k]。
an alternating current shunt: after the original data is subjected to IIR data filtering, FFT base 4 (1024 points) calculation processing is carried out on the filtered data, the fundamental wave value and the harmonic wave value of the signals are separated, calculation processing is carried out, the obtained data are subjected to per unit processing, and finally PWM output is carried out. By adopting the technology of the scheme, the accurate detection of the small signal direct current leakage under the condition of the A-level alternating current mixing interference with the signal bandwidth of 25kHz and 512 times can be realized.
An alternating current shunt:
the in-situ mixing disturbance current signal can be expressed as:
the signal is sampled at high speed by an ADC, and the original data (alternating current signal) can be expressed as:
wherein,,alternating current mixing interference signal amplitude:
and finally, the output direct current leakage standard signal and the alternating current mixing interference standard signal are both analog voltage signals of 0-5V.
Example 4
In the embodiment, MATLAB is adopted to simulate an original signal DC 150mA, an alternating-current mixing interference signal is fundamental wave 1000mA, the content of each subharmonic is 100mA, and the frequency point of the original signal is as follows: units of data in TABLE: hz. The design distribution of the interference signal frequency points is as follows:
TABLE＝[50，100,150,200,250,300,350,400,450,500,550,600,650,700,
4000,4050,4100,4150,4200,4250,4300,4350,4400,4450,4500,4550,4600,4650,4700,4750,4800,4850,4900,4950,5000,5050]
the analog generated ac mixed interference signal waveform is shown in fig. 5, which approximates the field interference waveform.
The digitally filtered waveform is shown in fig. 6, with an output of approximately 146.4mA and an actual error of less than 3%.
It will be appreciated by those skilled in the art that embodiments of the present application may be provided as a method, system, or computer program product. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein. Those of ordinary skill in the art will appreciate that implementing all or part of the above facts and methods may be accomplished by a program to instruct related hardware, the program involved or the program may be stored in a computer readable storage medium, the program when executed comprising the steps of: the corresponding method steps are introduced at this time, and the storage medium may be a ROM/RAM, a magnetic disk, an optical disk, or the like.
These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.
The foregoing description of the embodiments has been provided for the purpose of illustrating the general principles of the invention, and is not meant to limit the scope of the invention, but to limit the invention to the particular embodiments, and any modifications, equivalents, improvements, etc. that fall within the spirit and principles of the invention are intended to be included within the scope of the invention.
Claims (10)
1. The small-signal direct current leakage detection method is characterized by comprising the following steps of:
step one: collecting an alternating current-direct current mixing signal and preprocessing; the alternating current-direct current mixing signal is an alternating current mixing interference current signal and a direct current leakage current signal;
step two: separating the alternating current mixing interference signal and the direct current leakage signal from the preprocessed data;
step three: and carrying out alternating current filtering quantization treatment on the alternating current mixing interference signal to obtain an alternating current mixing interference standard signal, and carrying out direct current filtering quantization treatment on the direct current leakage signal to obtain a direct current leakage standard signal.
2. The method for detecting small-signal direct current leakage according to claim 1, wherein the collection of the alternating current-direct current mixed signal is realized based on a fluxgate technology.
3. The small signal direct current leakage detection method according to claim 1, wherein the preprocessing comprises the steps of:
high-speed sampling is carried out on the alternating current-direct current mixed signal to obtain original data;
and (3) performing spectrum leakage compensation on the original data, and inputting the compensated original data into an IIR elliptic filter for digital filtering.
4. The small-signal direct-current leakage detection method according to claim 1, wherein the direct-current leakage standard signal and the alternating-current mixing interference signal output analog voltage signals with the voltage of 0-5V.
5. A small signal dc leakage detection method according to claim 3, wherein the system samples a high speed core CPU, and the ADC is a CPU internal high speed ADC.
6. A small-signal direct current leakage detection method according to claim 3, wherein said direct current filtering quantization process comprises the steps of:
t1, sequentially performing Sinc4 filter filtering, 1 st RC low-pass filtering, 2 nd elliptic filter filtering and 2 nd RC low-pass filtering on the direct current signal to obtain a direct current signal L;
and T2, carrying out per unit processing on the direct current signal L to obtain a direct current leakage standard signal.
7. The method for small-signal dc leakage detection according to claim 6, wherein the filtering in T1 follows:
y[k]＝a×(y[k-1]-x[k])+x[k]
a is a filtered coefficient, k is a filtered position point, x k is an original value of an input signal, y k is a filtered output value, and y k-1 is a last filtered output value.
8. A small-signal direct current leakage detection method according to claim 3, wherein said alternating current filtering quantization process comprises the steps of:
for alternating current mixing interference signalsThe fundamental wave value and the harmonic value are separated by FFT base 4 calculation processing: after FFT calculation processing, get
Wherein,,
k represents the harmonic order, N represents the number of sampling points of a periodic signal,representing the DC component of the signal, a k Representing the real part calculation formula of the radix 4-FFT complex number, b k Representing a base 4-FFT complex imaginary part calculation formula, u representing a signal phase;
calculating an alternating current signal amplitude based on the fundamental wave value and the harmonic wave value:
and carrying out per unit processing on the amplitude of the alternating current mixing interference signal to obtain an alternating current mixing interference standard signal.
9. The method for detecting small-signal direct current leakage according to claim 1, wherein the alternating current mixing interference signal output is:
PWM_I AC ＝(I AC_SAMPLE -I AC_CALIB_ZERO )*10000/(I AC_CALIB_FULL -I AC_CALIB_ZERO )
wherein: PWM_I AC The resolution ratio is one ten thousandth of the output value of alternating current mixing interference current;
I AC_SAMPLE sampling per unit value for alternating current mixing interference current in real time;
I AC_CALIB_FULL the method comprises the steps of (1) calibrating a forward full value of an alternating-current mixing interference current signal;
I AC_CALIB_ZERO zero calibration value of alternating-current mixing interference current signals;
the output of the direct current leakage standard signal is as follows:
PWM_I DC ＝(I DC_SAMPLE -I DC_CALIB_ZERO )*10000/(I DC_CALIB_FULL -I DC_CALIB_ZERO ).
wherein: PWM_I DC Output value of DC leakage current, resolution is one ten thousandth;
I DC_SAMPLE sampling per unit value of direct current leakage current in real time;
I DC_CALIB_FULL direct current leakage current signal positive full value calibration value;
I DC_CALIB_ZERO zero calibration value of direct current leakage current signal.
10. A small-signal direct current leakage detection system, characterized in that it is configured to implement the small-signal direct current leakage detection method according to any one of claims 1 to 9, comprising:
the acquisition module is used for acquiring the alternating current-direct current mixing signals and preprocessing the alternating current-direct current mixing signals; the alternating current-direct current mixing signal is an alternating current mixing interference current signal and a direct current leakage current signal; the acquisition module is a fluxgate acquisition device;
the preprocessing module is used for separating alternating current mixing interference signals and direct current leakage signals from the preprocessed data;
and the detection module is used for carrying out alternating current filtering quantization processing on the alternating current mixing interference signal to obtain an alternating current mixing interference standard signal, and carrying out direct current filtering quantization processing on the direct current leakage signal to obtain a direct current leakage standard signal.
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| CN116660793A (en) * | 2023-07-25 | 2023-08-29 | 青岛鼎信通讯股份有限公司 | AC/DC leakage detection method based on flexible DC voltage regulating device |
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2023
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116660793A (en) * | 2023-07-25 | 2023-08-29 | 青岛鼎信通讯股份有限公司 | AC/DC leakage detection method based on flexible DC voltage regulating device |
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