A 220V direct current system operation state real-time monitoring method

Abstract

The present application relates to the technical field of direct current system monitoring, in particular to a 220V direct current system operation state real-time monitoring method. The method comprises: obtaining the ripple degree characteristic value of the current output direct current voltage window and the historical output direct current voltage window, and obtaining the distortion degree characteristic value of the current input voltage window and the historical input voltage window according to the harmonics in the frequency spectrum signal of the input voltage window; obtaining the performance coefficient at the current moment according to the ripple degree characteristic value and the distortion degree characteristic value, and obtaining the target abnormality degree index value at the current moment according to the mean value difference between the current temperature window and the historical temperature window and the performance coefficient at the current moment; monitoring the operation state of the rectifier module at the current moment according to the target abnormality degree index value at the current moment; and the present application can improve the accuracy and reliability of monitoring the operation state of the rectifier module in the 220V direct current system.

Description

A method for real-time monitoring of the operating status of a 220V DC system Technical Field

[0001] This invention relates to the field of DC system monitoring technology, specifically to a method for real-time monitoring of the operating status of a 220V DC system. Background Technology

[0002] The 220V DC system is a critical control power source in power infrastructure such as power plants and substations. This system typically converts three-phase AC power into 220V DC power via a rectifier module, providing a stable power supply to various loads in the distribution system. When a 220V DC system malfunctions, it not only affects the system's stability but also leads to damage to electrical equipment, increased safety risks, and a series of other problems. Therefore, monitoring the operating status of the 220V DC system is crucial. Currently, monitoring the operating status of the DC system primarily focuses on the rectifier module. In other words, monitoring the operating status of the rectifier module is a direct component of the overall 220V DC system operation status monitoring, as the rectifier module is a core component of the DC system.

[0003] In existing technologies, the operating status of rectifier modules is generally monitored based on the real-time monitored DC output voltage. However, this monitoring method, which only focuses on the output DC voltage, can lead to inaccurate and unreliable monitoring results. For example, aging or other abnormalities of the electronic components inside the rectifier module may not directly cause the output DC voltage to be outside the specified range, but may cause changes in the stability or ripple of the output DC voltage. Therefore, how to improve the accuracy and reliability of monitoring the operating status of rectifier modules, thereby ensuring the accuracy and reliability of monitoring the operating status of 220V DC systems, has become an urgent problem to be solved. Summary of the Invention

[0004] To address the above problems, this invention provides a method for real-time monitoring of the operating status of a 220V DC system, the specific technical solution of which is as follows:

[0005] One embodiment of the present invention provides a method for real-time monitoring of the operating status of a 220V DC system, comprising the following steps:

[0006] Obtain the current output DC voltage window, current input voltage window, current temperature window, historical output DC voltage window, historical input voltage window, and historical temperature window of the rectifier module in the 220V DC system at the current moment;

[0007] Based on the deviation between the output DC voltage in the output DC voltage window and the theoretical output DC voltage, the ripple characterization values ​​of the current output DC voltage window and the historical output DC voltage window are obtained. Based on the harmonics in the spectrum signal of the input voltage window, the distortion characterization values ​​of the current input voltage window and the historical input voltage window are obtained.

[0008] Based on the ripple degree characterization value and the distortion degree characterization value, the performance coefficient at the current moment is obtained, and based on the mean difference between the current temperature window and the historical temperature window and the performance coefficient at the current moment, the target anomaly degree index value at the current moment is obtained.

[0009] The operating status of the rectifier module is monitored based on the target anomaly index value at the current moment.

[0010] Beneficial Effects: This invention first obtains the current output DC voltage window, current input voltage window, current temperature window, historical output DC voltage window, historical input voltage window, and historical temperature window of the rectifier module in a 220V DC system at the current moment. Then, based on the deviation between the output DC voltage in the output DC voltage window and the theoretical output DC voltage, it obtains the ripple level characterization values ​​of the current output DC voltage window and the historical output DC voltage window. Based on the harmonics in the spectrum signal of the input voltage window, it obtains the distortion level characterization values ​​of the current input voltage window and the historical input voltage window. Finally, based on the ripple level characterization values ​​and the distortion level characterization values, it obtains the performance coefficient at the current moment, and based on the mean difference between the current temperature window and the historical temperature window... The present invention obtains the target anomaly index value at the current moment by combining the performance coefficient at the current moment with the target anomaly index value at the current moment; finally, it monitors the operating status of the rectifier module at the current moment based on the target anomaly index value at the current moment; and the present invention, by combining the target anomaly index value obtained by combining the ripple degree, distortion degree and temperature, can accurately and reliably monitor whether the rectifier module is in an abnormal operating state or whether there is a trend of abnormal operation, thereby improving the accuracy and reliability of monitoring the operating status of the rectifier module in the 220V DC system. In other words, the present invention improves the accuracy and reliability of monitoring the operating status of the rectifier module in the 220V DC system by improving the accuracy and reliability of monitoring the operating status of the rectifier module in the 220V DC system. Attached Figure Description

[0011] To more clearly illustrate the technical solutions and advantages in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0012] Figure 1 is a flowchart of a method for real-time monitoring of the operating status of a 220V DC system according to the present invention. Detailed Implementation

[0013] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention are within the protection scope of the embodiments of the present invention.

[0014] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art.

[0015] This embodiment provides a method for real-time monitoring of the operating status of a 220V DC system, detailed as follows:

[0016] As shown in Figure 1, the real-time monitoring method for the operating status of this 220V DC system includes the following steps:

[0017] Step S001: Obtain the current output DC voltage window, current input voltage window, current temperature window, historical output DC voltage window, historical input voltage window, and historical temperature window of the rectifier module in the 220V DC system at the current moment.

[0018] The main objective of this embodiment is to improve the accuracy and reliability of monitoring the operating status of the rectifier module, thereby ensuring the accuracy and reliability of monitoring the operating status of the 220V DC system.

[0019] Since the input voltage, output DC voltage, and temperature of the rectifier module reflect its operating status, monitoring its operating status requires collecting these parameters. Furthermore, for ease of analysis and understanding, this embodiment will subsequently monitor the operating status of a rectifier module within any 220V DC system to achieve the goal of monitoring the operating status of that 220V DC system. Therefore, it can be seen that the data collected in this embodiment all pertain to the same rectifier module. That is, to monitor the operating status of the rectifier module, this embodiment needs to collect the input voltage, output DC voltage, and temperature of the rectifier module in real time. Moreover, this embodiment requires that the input voltage, output DC voltage, and temperature of the rectifier module be collected synchronously. At each acquisition moment, the input voltage, output DC voltage, and temperature of the rectifier module need to be acquired. In this embodiment, the input voltage of the rectifier module refers to the external power supply voltage supplied to the rectifier module; the temperature of the rectifier module is the surface temperature of the rectifier module casing; and the output DC voltage of the rectifier module refers to the DC voltage with constant direction but fluctuating amplitude after converting AC power. In addition, the frequency for acquiring the input voltage, output DC voltage, and temperature of the rectifier module generally needs to be determined based on the highest frequency component of the signal, the accuracy of the monitoring target, and other actual conditions. For example, in this embodiment, the acquisition frequency can be set to 1 Hz or 100 Hz. Generally, the input voltage, output DC voltage, and temperature of the rectifier module are acquired by a multi-channel synchronous sampling ADC.

[0020] Therefore, this embodiment can obtain the input voltage, output DC voltage, and temperature of the rectifier module at each acquisition moment through the above process. After obtaining the input voltage, output DC voltage, and temperature of the rectifier module at each acquisition moment, this embodiment next needs to obtain the data window, which is the basis for subsequent monitoring of the rectifier module's operating status. The specific process for obtaining the data window is as follows:

[0021] First, a preset sliding time window is constructed. In specific applications, the implementer needs to set the length of the preset sliding time window according to actual conditions such as the acquisition frequency. For example, in this embodiment, the length of the preset sliding time window is set to 1 minute. Then, the rightmost end of the preset sliding time window is placed at the current moment, and the time window that has been placed but has not yet been slid is taken as the current time window. That is, the current time window consists of the current moment and one minute before the current moment. In this embodiment, the current moment is the current acquisition moment. Then, the current time window is slid to the left to obtain the historical time window under each slide. The sliding stops when the window contains the starting acquisition moment of data acquisition from the rectifier module. In this way, multiple time windows can be obtained, and the obtained time windows include the current time window and multiple historical time windows. In addition, in this embodiment, the implementer can set the sliding step size according to actual conditions such as the accuracy requirements for subsequent monitoring of the rectifier module's operating status. For example, in this embodiment, the sliding step size of the window can be set to be consistent with the data acquisition time interval of the rectifier module. So, if the frequency of acquiring the input voltage, output DC voltage, and temperature of the rectifier module in this embodiment is 1 Hz, the sliding step size of the window is 1 second.

[0022] After obtaining the time window, a data window is obtained based on the data in each time window. Specifically, for any time window: the data window constructed by collecting the input voltages of all rectifier modules within the time window in the order of acquisition is recorded as the input voltage window corresponding to that time window; the data window constructed by collecting the temperatures of all rectifier modules within the time window in the order of acquisition is recorded as the temperature window corresponding to that time window; and the data window constructed by collecting the output DC voltages of all rectifier modules within the time window in the order of acquisition is recorded as the output DC voltage window corresponding to that time window. Then, the input voltage window, temperature window, and output DC voltage window corresponding to the current time window are all recorded as the current output DC voltage window, current input voltage window, and current temperature window of the rectifier module in the 220V DC system at the current moment. The input voltage window, temperature window, and output DC voltage window corresponding to the historical time window are all recorded as the historical output DC voltage window, historical input voltage window, and historical temperature window of the rectifier module in the 220V DC system at the current moment.

[0023] Therefore, this embodiment obtains the current output DC voltage window, current input voltage window, current temperature window, historical output DC voltage window, historical input voltage window, and historical temperature window of the rectifier module in the 220V DC system at the current moment through the above process.

[0024] Step S002: Based on the deviation between the output DC voltage in the output DC voltage window and the theoretical output DC voltage, obtain the ripple characterization value of the current output DC voltage window and the historical output DC voltage window; based on the harmonics in the spectrum signal of the input voltage window, obtain the distortion characterization value of the current input voltage window and the historical input voltage window.

[0025] Since the ripple level characterization value of the output DC voltage window and the distortion level characterization value of the input voltage window can reflect the performance or operating status of the rectifier module, this embodiment will first obtain the ripple level characterization value of the current output DC voltage window and the historical output DC voltage window based on the deviation between the output DC voltage in the output DC voltage window and the theoretical output DC voltage, and then obtain the distortion level characterization value of the current input voltage window and the historical input voltage window based on the fundamental amplitude value in the spectrum signal of the input voltage window. Furthermore, the specific process for obtaining the ripple level characterization value of the current output DC voltage window and the historical output DC voltage window in this embodiment is as follows: For the current output DC voltage window:

[0026] First, the theoretical output DC voltage is obtained. In this embodiment, the theoretical output DC voltage is 220V. Then, based on the deviation between the current output DC voltage and the theoretical output DC voltage, the deviation window corresponding to the current output DC voltage window is obtained. The a-th deviation in the deviation window corresponding to the current output DC voltage window is the absolute value of the difference between the a-th output DC voltage in the current output DC voltage window and the theoretical output DC voltage. The deviation between the output DC voltage and the theoretical output DC voltage can reflect the operating status or performance of the rectifier module. Then, the maximum deviation in the deviation window corresponding to the current output DC voltage window is obtained, and the average value of all deviations in the deviation window corresponding to the current output DC voltage window is obtained and recorded as the average deviation of the corresponding deviation window. The ripple level of the current output DC voltage window is determined by multiplying the maximum deviation within the corresponding deviation window by the average deviation within the same window. This product is then used as the ripple level characterization value. A larger ripple level characterization value indicates a higher degree of DC ripple in the output DC voltage window, meaning a larger maximum deviation and a larger average deviation within the corresponding deviation window. Conversely, a smaller ripple level characterization value indicates a higher degree of DC ripple in the output DC voltage window. The DC ripple level reflects the performance of the rectifier module. Furthermore, due to technological limitations, reduced filter capacitor capacity, or performance degradation of the rectifier circuit, the DC output of the rectifier module may contain AC components of a certain frequency and amplitude. This impure voltage fluctuation is called DC ripple.

[0027] Furthermore, the method for obtaining the ripple level characterization value of the historical output DC voltage window in this embodiment is the same as the method for obtaining the ripple level characterization value of the current output DC voltage window, so this embodiment will not describe it in detail.

[0028] In this embodiment, the specific process of obtaining the distortion characterization values ​​of the current input voltage window and the historical input voltage window is as follows: For the current output DC voltage window:

[0029] First, a Fast Fourier Transform (FFT) is performed on the current input voltage window to obtain its spectral signal. Then, the sum of the amplitudes corresponding to all frequencies in the spectral signal of the current input voltage window is calculated and recorded as the total spectral amplitude. Next, the amplitude of the frequency value in the spectral signal of the current input voltage window that equals the fundamental frequency is obtained and recorded as the fundamental amplitude, which is the amplitude at the fundamental frequency. The fundamental frequency is the amplitude at the frequency point corresponding to the fundamental voltage waveform, such as the fundamental frequency of alternating current, which is generally 50 Hz. Then, the ratio of the total spectral amplitude to the fundamental amplitude is calculated and recorded as the distortion characterization value of the current input voltage window. Furthermore, when the total spectral amplitude is equal to the fundamental amplitude... A larger amplitude ratio, meaning a larger distortion value for the current input voltage window, indicates a greater degree of distortion or higher frequency harmonic content in the input voltage waveform within that window. Conversely, a smaller distortion value indicates a smaller degree of distortion. In other words, the more high-frequency harmonic components the input voltage contains in the current window, the greater the distortion or higher the frequency harmonic content. Furthermore, since the method for obtaining the distortion value of historical input voltage windows is the same as that for the current input voltage window, it will not be described in detail in this embodiment.

[0030] When the input power supply contains a significant amount of high-frequency harmonics, these harmonics may be superimposed on the rectified voltage through the rectifier circuit, increasing the output voltage fluctuation and consequently increasing the DC output ripple. Simultaneously, harmonics may also affect the efficiency of internal filtering components (such as filter capacitors and inductors) within the rectifier module, reducing their ability to suppress AC components and making the output DC more unstable. Therefore, there is a certain correlation between the input power supply quality and the output DC ripple level. Furthermore, the correlation between input power supply quality and output DC ripple level can reflect the operating status or performance of the rectifier module; that is, a comprehensive analysis of the ripple level and the distortion of the input voltage window can reflect the operating status or performance of the rectifier module.

[0031] Therefore, this embodiment obtains the ripple characterization values ​​of the current output DC voltage window and the historical output DC voltage window, as well as the distortion characterization values ​​of the current input voltage window and the historical input voltage window through the above process.

[0032] Step S003: Based on the ripple degree characterization value and the distortion degree characterization value, obtain the performance coefficient at the current moment, and based on the mean difference between the current temperature window and the historical temperature window and the performance coefficient at the current moment, obtain the target anomaly degree index value at the current moment.

[0033] When the rectifier module's performance is relatively stable, or when its operating state is good, not only will the rectifier module perform better in rectifying AC power, but also, when the harmonic level in the input current increases, the change in the output current ripple level will be smaller. That is, when the distortion level of the input voltage window increases while the ripple level of the output DC voltage decreases, or when the change in the distortion level of the input voltage window and the change in the ripple level of the output DC voltage are not in the same direction, it indicates that the change in the output DC voltage ripple level of the rectifier module is less affected by the change in the distortion level of the input voltage, which also indicates that the rectifier module's operating state or performance is good. Therefore, after obtaining the ripple level characterization value of the output DC voltage window and the distortion level of the input voltage window, this embodiment will next obtain the performance coefficient at the current moment based on the ripple level characterization value and the distortion level characterization value. The performance coefficient reflects the performance of the rectifier module. The specific process for obtaining the performance coefficient at the current moment is as follows:

[0034] First, a predetermined first number of historical output DC voltage windows closest to the current output DC voltage window are obtained and denoted as the nearest historical output DC voltage windows corresponding to the current output DC voltage window. Similarly, a predetermined first number of historical input voltage windows closest to the current input voltage window are obtained and denoted as the nearest input DC voltage windows corresponding to the current input voltage window. Then, the time series consisting of the ripple level characterization value of the current output DC voltage window and the ripple level characterization values ​​of all the nearest historical output DC voltage windows corresponding to the current output DC voltage window is denoted as the first sequence to be analyzed corresponding to the current output DC voltage window. The time series consisting of the distortion degree characterization value of the current input voltage window and the distortion degree characterization values ​​of all the nearest historical input voltage windows corresponding to the current input voltage window is denoted as the second analysis sequence corresponding to the current input voltage window. Then, the Spearman rank correlation coefficient between the first analysis sequence corresponding to the current output DC voltage window and the second analysis sequence corresponding to the current input voltage window is calculated. The Spearman rank correlation coefficient is added to a preset second constant, and the result of negative correlation mapping is denoted as the first index value, which is exp(-(R0+c2)), where exp is an exponential function with base e. 0 represents the Spearman rank correlation coefficient, and c2 is a preset second constant. This preset second constant is to prevent the value from being less than 0 during negative mapping. Since the Spearman rank correlation coefficient ranges from -1 to 1, a larger value indicates a stronger correlation between the changes in the first and second sequences being analyzed. Therefore, this embodiment requires c2 to be greater than or equal to 1; for example, it can be set to 2. Then, the mean of all ripple level characterization values ​​in the first sequence being analyzed is recorded as the mean of the first sequence being analyzed, and the mean of all distortion level characterization values ​​in the second sequence being analyzed is recorded as the mean of the second sequence being analyzed. Next, the ratio of the mean of the second sequence being analyzed to the mean of the first sequence being analyzed is calculated and recorded as the second index value. If the mean of the second sequence being analyzed is 0, then... As the second indicator value, c1 is a preset first constant, the purpose of which is to prevent the denominator from being 0. N1 is the mean of the first sequence to be analyzed, and N2 is the mean of the second sequence to be analyzed. Finally, the product of the first indicator value and the second indicator value is used as the performance coefficient at the current moment. In specific applications, the implementer needs to set the preset first number of values ​​according to the actual situation. For example, in this embodiment, the preset first number of values ​​can be set to 3.

[0035] Furthermore, the specific formula for calculating the performance coefficient at the current moment is as follows:

[0036]

[0037] Where W is the performance coefficient at the current moment, and exp is an exponential function with base e, the purpose of which is to... Perform a negative-positive correlation mapping, where P is the value of the second indicator; and when The larger the value of P, the less interference the change in the degree of distortion of the local input voltage has on the change in the degree of ripple of the output DC voltage of the rectifier module. In this case, the rectifier module's operating state may be more stable and its performance better. When P is larger, it indicates that the rectifier module's filtering capability is better and its operating state or performance is better. Therefore, when W is larger, it indicates that the rectifier module's performance or operating state may be better.

[0038] Therefore, this embodiment obtains the performance coefficient at the current moment through the above process. However, the performance of electronic components in the rectifier module may be affected by temperature, resulting in performance drift. For example, temperature changes can cause changes in the resistance value of the internal circuits of electronic components, thus making the reliability of the coefficients calculated above reflecting the performance of the rectifier module less reliable. In order to further improve the monitoring of the operating status of the rectifier module, this embodiment, after obtaining the performance coefficient at the current moment, combines the module's temperature data to obtain an anomaly index value. That is, this embodiment will then obtain the target anomaly index value at the current moment based on the mean difference between the current temperature window and the historical temperature window and the performance coefficient at the current moment; and the specific process of obtaining the target anomaly index value at the current moment is as follows:

[0039] First, the average value of all temperatures within the temperature window is calculated and recorded as the average temperature value of the corresponding temperature window. Then, a preset second number of historical temperature windows closest to the current temperature window are obtained and recorded as the nearest historical temperature windows corresponding to the current temperature window. Next, the temperature characteristic value corresponding to the current moment is obtained based on the difference between the average temperature value of the current temperature window and the average temperature value of the nearest historical temperature windows corresponding to the current temperature window. Immediately afterwards, a preset second number of historical acquisition times closest to the current moment are obtained and recorded as the nearest historical times of the current moment. Then, the performance coefficients of each nearest historical time are obtained, and the process of obtaining the performance coefficients of the nearest historical times is the same as that of the current moment, so it will not be described in detail in this embodiment. In specific applications, the implementer can set the value of the preset second number according to the actual situation. For example, in this embodiment, the value of the preset second number can be set to 7. Then, the performance characteristic value corresponding to the current moment is obtained based on the difference between the performance coefficient of the current moment and the performance coefficient of the nearest historical times of the current moment, and the temperature characteristic value and performance characteristic value corresponding to each nearest historical time of the current moment are obtained.

[0040] After obtaining the temperature and performance characteristic values ​​corresponding to the current moment and the nearest historical moments, this embodiment records the sequence of temperature characteristic values ​​corresponding to all the nearest historical moments as the historical temperature characteristic value sequence at the current moment, and the sequence of performance characteristic values ​​corresponding to all the nearest historical moments as the historical performance characteristic value sequence at the current moment. Then, based on the temperature and performance characteristic values, the historical temperature and performance characteristic value sequences, the initial anomaly index value at the current moment is obtained. After obtaining the initial anomaly index value at the current moment, the initial anomaly index values ​​at all the nearest historical moments are obtained. Then, based on the initial anomaly index value at the current moment and the initial anomaly index values ​​at all the nearest historical moments, the target anomaly index value at the current moment is obtained. The larger the target anomaly index value at the current moment, the greater the likelihood that the rectifier module is in an abnormal operating state or has a tendency to operate abnormally.

[0041] In this embodiment, the specific process for obtaining the temperature feature value is as follows: For the current moment, the sequence of temperature averages of the second number of historical temperature windows closest to the current temperature window is denoted as the historical temperature average sequence. A temperature average difference sequence is obtained, and the result of negatively correlated mapping of the mean of the temperature average difference sequence is used as the temperature feature value corresponding to the current moment. The b-th temperature average difference in the temperature average difference sequence is the absolute value of the difference between the temperature average of the current temperature window and the b-th temperature average in the historical temperature average sequence. Furthermore, the method for obtaining the temperature feature value corresponding to the nearest historical moment of the current moment is the same as the method for obtaining the temperature feature value corresponding to the current moment, and therefore will not be described in detail. Additionally, the calculation expression for obtaining the temperature feature value corresponding to the current moment is: Where exp() is an exponential function with base e, B is the number of temperature mean values ​​in the historical temperature mean series, and T0 is the temperature mean value of the current temperature window. It is the b-th temperature mean in the historical temperature mean sequence, and the temperature feature value is mainly used to obtain the subsequent initial anomaly degree index value.

[0042] In this embodiment, the specific process for obtaining the performance feature value is as follows: For the current moment, the sequence of performance coefficients formed by all the performance coefficients of the nearest historical moments is recorded as the historical performance coefficient sequence. The performance coefficient difference sequence is obtained, and the result of negatively correlated mapping of the mean of the performance coefficient difference sequence is used as the performance feature value corresponding to the current moment. The performance feature value corresponding to the current moment is... Nt is the mean of the performance coefficient difference sequence, and the c-th performance coefficient difference in the performance coefficient difference sequence is the absolute value of the difference between the performance coefficient at the current time and the c-th historical performance coefficient in the historical performance coefficient sequence. Since the method for obtaining the performance feature value corresponding to the nearest historical time of the current time in this embodiment is the same as the method for obtaining the performance feature value corresponding to the current time, it will not be described in detail. The performance feature value is mainly used for obtaining the initial anomaly index value in the subsequent process.

[0043] In this embodiment, the specific process of obtaining the initial anomaly index value at the current moment based on the temperature characteristic value and performance characteristic value corresponding to the current moment, the historical temperature characteristic value sequence, and the historical performance characteristic value sequence is as follows:

[0044] First, based on the differences between the current temperature feature value and each temperature feature value in the historical temperature feature value sequence, and the differences between the current performance feature value and each performance feature value in the historical performance feature value sequence, the current feature coefficient is obtained. Then, based on the differences between each historical temperature feature value in the historical temperature feature value sequence and other historical temperature feature values ​​(excluding the corresponding historical temperature feature value), the unprocessed comprehensive difference corresponding to each historical temperature feature value in the historical temperature feature value sequence is obtained. Finally, based on the differences between each historical performance feature value in the historical performance feature value sequence and other historical performance feature values ​​(excluding the corresponding historical performance feature value), the unprocessed comprehensive difference is obtained. The process begins by calculating the unprocessed comprehensive difference corresponding to each historical performance feature value in the historical performance feature value sequence. Next, the mean of the unprocessed comprehensive differences corresponding to all historical temperature feature values ​​in the historical temperature feature value sequence is calculated and recorded as the first historical feature mean. The mean of the unprocessed comprehensive differences corresponding to all historical performance feature values ​​in the historical performance feature value sequence is then calculated and recorded as the second historical feature mean. The ratio of the first historical feature mean to the second historical feature mean is calculated and recorded as the nearest neighbor historical feature coefficient. Finally, the absolute value of the difference between the nearest neighbor historical feature coefficient and the current feature coefficient is calculated and used as the initial anomaly index value at the current time. In other words, the initial anomaly index value at the current time is [value missing]. Where S0 is the nearest neighbor historical characteristic coefficient and S1 is the current characteristic coefficient; in addition, since the nearest neighbor historical characteristic coefficient and the current characteristic coefficient are relatively close when the rectifier module is operating normally, the greater the difference between the nearest neighbor historical characteristic coefficient and the current characteristic coefficient, the greater the possibility that the rectifier module is in an abnormal operating state or has a tendency to operate abnormally. On the other hand, the smaller the difference between the nearest neighbor historical characteristic coefficient and the current characteristic coefficient, the greater the possibility that the rectifier module is in a normal operating state.

[0045] In this embodiment, the specific process for obtaining the current feature coefficient is as follows: First, a first difference sequence is obtained based on the difference between the temperature feature value corresponding to the current time and each temperature feature value in the historical temperature feature value sequence. The d-th first difference in the first difference sequence is the absolute value of the difference between the temperature feature value corresponding to the current time and the d-th historical temperature feature value in the historical temperature feature value sequence. Then, the cumulative result of all first differences in the first difference sequence is calculated and used as the first comprehensive difference. Next, a second difference sequence is obtained based on the difference between the performance feature value corresponding to the current time and each performance feature value in the historical performance feature value sequence. The f-th second difference in the second difference sequence is the absolute value of the difference between the performance feature value corresponding to the current time and the f-th historical performance feature value in the historical performance feature value sequence. The cumulative result of all second differences in the second difference sequence is calculated and used as the second comprehensive difference. Finally, the ratio of the first comprehensive difference to the second comprehensive difference is calculated and recorded as the current feature coefficient at the current time. The calculation expression for the current feature coefficient at the current time is:

[0046]

[0047] Where S0 is the current feature coefficient at the current moment, K1 is the total number of historical temperature feature values ​​in the historical temperature feature value sequence, K2 is the total number of historical performance feature values ​​in the historical performance feature value sequence, M0 is the temperature feature value corresponding to the current moment, and U0 is the performance feature value corresponding to the current moment. This represents the d-th historical temperature feature value in the historical temperature feature value sequence. It is the f-th historical performance feature value in the historical performance feature value sequence.

[0048] In this embodiment, the specific process for obtaining the comprehensive difference to be processed is as follows: For the h-th historical temperature feature value in the historical temperature feature value sequence: First, obtain the sequence constructed from the remaining historical temperature feature values ​​excluding the h-th historical temperature feature value in the historical temperature feature value sequence, and denot it as the feature subsequence of the h-th historical temperature feature value; then, based on the h-th historical temperature feature value and the feature subsequence of the h-th historical temperature feature value, obtain the difference sequence to be processed corresponding to the h-th historical temperature feature value, and the j-th difference to be processed in the difference sequence to be processed is the h-th historical temperature feature value. The absolute value of the difference between the h-th historical temperature feature value and the j-th historical temperature feature value in the feature subsequence of the h-th historical temperature feature value is calculated. Then, the cumulative result of all the unprocessed differences in the unprocessed difference sequence is calculated and used as the unprocessed comprehensive difference value corresponding to the h-th historical temperature feature value. In addition, the methods for obtaining the unprocessed comprehensive difference values ​​corresponding to other historical temperature feature values ​​in the historical temperature feature value sequence and the unprocessed comprehensive difference values ​​corresponding to each performance feature value in the historical performance feature value sequence are the same as the methods for obtaining the unprocessed comprehensive difference value corresponding to the h-th historical temperature feature value, so they will not be described in detail.

[0049] In this embodiment, the specific process of obtaining the target anomaly index value at the current moment based on the initial anomaly index value at the current moment and the initial anomaly index values ​​at all neighboring historical moments is as follows: Calculate the mean of the initial anomaly index values ​​at all neighboring historical moments at the current moment, and record it as the neighboring historical mean; calculate the ratio of the initial anomaly index value at the current moment to the neighboring historical mean, and use this ratio as the target anomaly index value at the current moment. That is, the target anomaly index value at the current moment is... Where Y0 is the initial anomaly index value at the current moment, and Y1 is the average of the initial anomaly index values ​​at all neighboring historical moments at the current moment. The larger the target anomaly index value at the current moment, the greater the growth trend of the anomaly at the current moment compared to the previous moment. When the anomaly at the current moment has a greater growth trend compared to the previous moment, it also indicates that the rectifier module is in an abnormal operating state or has a greater possibility of an abnormal operating trend.

[0050] Therefore, this embodiment can obtain the target anomaly index value at the current moment through the above process.

[0051] Step S004: Monitor the operating status of the rectifier module at the current moment based on the target anomaly index value at the current moment.

[0052] Since the target anomaly level index value at the current moment can reflect the abnormal operation of the rectifier module or the trend of abnormal operation, this embodiment will monitor the operating status of the rectifier module at the current moment based on the target anomaly level index value at the current moment. The specific process is as follows: First, it is determined whether the target anomaly level index value at the current moment is greater than the preset anomaly threshold. If it is, it indicates that the rectifier module is in an abnormal operating state or has a trend of abnormal operation. In this case, it is necessary to immediately issue an alarm for the rectifier module and switch to backup DC power supply to power the corresponding equipment, thereby realizing the monitoring of the operating status of the 220V DC system. If it is determined that the target anomaly level index value at the current moment is less than or equal to the preset anomaly threshold, it indicates that the rectifier module is in an abnormal operating state or has a trend of abnormal operation. In normal operation, no alarm will be triggered for the rectifier module. In specific applications, implementers need to set a preset anomaly threshold based on the target anomaly index value range, experimental statistics, and other actual conditions. Since the target anomaly index value at the current moment is the ratio of the initial anomaly index value at the current moment to the average of the initial anomaly index values ​​at the nearest historical moments, a ratio greater than 1 indicates that the anomaly level at the current moment is increasing compared to the previous moment. When the anomaly level at the current moment is increasing compared to the previous moment, it indicates that the rectifier module is in an abnormal operating state or is likely to have an abnormal operating trend. Therefore, this embodiment requires the preset anomaly threshold to be greater than 1. For example, in this embodiment, the preset anomaly threshold can be set to 1.2.

[0053] Thus, this embodiment has completed the monitoring of the operating status of the rectifier module in the 220V DC system through the above process, thereby ensuring the accuracy and reliability of the monitoring of the operating status of the 220V DC system.

[0054] In summary, this embodiment first obtains the current output DC voltage window, current input voltage window, current temperature window, historical output DC voltage window, historical input voltage window, and historical temperature window of the rectifier module in the 220V DC system at the current moment. Then, based on the deviation between the output DC voltage in the output DC voltage window and the theoretical output DC voltage, it obtains the ripple level characterization values ​​of the current output DC voltage window and the historical output DC voltage window. Based on the harmonics in the spectrum signal of the input voltage window, it obtains the distortion level characterization values ​​of the current input voltage window and the historical input voltage window. Finally, based on the ripple level characterization values ​​and the distortion level characterization values, it obtains the performance coefficient at the current moment, and based on the average value between the current temperature window and the historical temperature window... The difference and the performance coefficient at the current moment are used to obtain the target anomaly index value at the current moment; finally, the operating status of the rectifier module at the current moment is monitored based on the target anomaly index value at the current moment; and this embodiment, by combining the target anomaly index value obtained from ripple degree, distortion degree and temperature, can accurately monitor whether the rectifier module is in an abnormal operating state or whether there is a trend of abnormal operation, thereby improving the accuracy and reliability of monitoring the operating status of the rectifier module in the 220V DC system. That is, this embodiment improves the accuracy and reliability of monitoring the operating status of the rectifier module in the 220V DC system by improving the accuracy and reliability of monitoring the operating status of the rectifier module in the 220V DC system.

[0055] The above-described embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.

Claims

1. A method for real-time monitoring of the operating status of a 220V DC system, characterized in that, The method includes the following steps: obtaining the current output DC voltage window, current input voltage window, current temperature window, historical output DC voltage window, historical input voltage window, and historical temperature window of the rectifier module in the 220V DC system at the current moment; obtaining the ripple characterization values ​​of the current output DC voltage window and the historical output DC voltage window based on the deviation between the output DC voltage in the output DC voltage window and the theoretical output DC voltage; and obtaining the distortion characterization values ​​of the current input voltage window and the historical input voltage window based on the harmonics in the spectrum signal of the input voltage window. Based on the ripple degree characterization value and the distortion degree characterization value, the performance coefficient at the current moment is obtained, and based on the mean difference between the current temperature window and the historical temperature window and the performance coefficient at the current moment, the target anomaly degree index value at the current moment is obtained. The operating status of the rectifier module is monitored based on the target anomaly index value at the current moment. The method for obtaining the performance coefficient at the current moment includes: recording the sequence formed by the ripple degree characterization value of the current output DC voltage window and the ripple degree characterization values ​​of the nearest preset first number of historical output DC voltage windows as the first analysis sequence; recording the sequence formed by the distortion degree characterization value of the current input voltage window and the distortion degree characterization values ​​of the nearest preset first number of historical input voltage windows as the second analysis sequence; calculating the Spearman rank correlation coefficient between the first analysis sequence and the second analysis sequence; recording the result of adding the Spearman rank correlation coefficient to a preset second constant and then performing a negative correlation mapping as the first index value; recording the ratio of the mean of the second analysis sequence to the mean of the first analysis sequence as the second index value; and recording the product of the first index value and the second index value as the performance coefficient at the current moment. The method for obtaining the target anomaly index value at the current moment includes: based on the temperature mean of the current temperature window and the temperature mean of the nearest preset second number of historical temperature windows... The difference between the mean values ​​of temperature and performance is used to obtain the temperature characteristic value corresponding to the current moment. A second set of nearest-neighbor historical moments are obtained, and the performance coefficients at these nearest-neighbor historical moments are obtained. The difference between the performance coefficient at the current moment and the performance coefficients at the nearest-neighbor historical moments is used to obtain the performance characteristic value corresponding to the current moment. The temperature characteristic value and performance characteristic value corresponding to the nearest-neighbor historical moments are obtained. A sequence of temperature characteristic values ​​corresponding to all nearest-neighbor historical moments at the current moment is recorded as the historical temperature characteristic value sequence, and a sequence of performance characteristic values ​​corresponding to all nearest-neighbor historical moments at the current moment is recorded as the historical performance characteristic value sequence. Based on the temperature characteristic value and performance characteristic value corresponding to the current moment, the historical temperature characteristic value sequence, and the historical performance characteristic value sequence, the initial anomaly index value at the current moment is obtained. The initial anomaly index value at the nearest-neighbor historical moments is obtained, and the mean of the initial anomaly index values ​​at all nearest-neighbor historical moments is recorded as the nearest-neighbor historical mean. The ratio of the initial anomaly index value at the current moment to the nearest-neighbor historical mean is used as the target anomaly index value at the current moment.

2. The method for real-time monitoring of the operating status of a 220V DC system as described in claim 1, characterized in that, The method for obtaining the ripple level characterization value includes: for the current output DC voltage window, obtaining a deviation window corresponding to the current output DC voltage window based on the deviation between the output DC voltage in the current output DC voltage window and the theoretical output DC voltage, wherein the a-th deviation in the deviation window is the absolute value of the difference between the a-th output DC voltage in the current output DC voltage window and the theoretical output DC voltage, and taking the product of the maximum deviation in the deviation window and the average deviation of the deviation window as the ripple level characterization value of the current output DC voltage window; the method for obtaining the ripple level characterization value of the historical output DC voltage window is the same as the method for obtaining the ripple level characterization value of the current output DC voltage window.

3. The method for real-time monitoring of the operating status of a 220V DC system as described in claim 1, characterized in that, The method for obtaining the distortion degree characterization value includes: for the current output DC voltage window, the summation result of the amplitudes corresponding to all frequencies in the spectrum signal of the current input voltage window is recorded as the total spectrum amplitude, the amplitude of the fundamental frequency in the spectrum signal of the current input voltage window is recorded as the fundamental amplitude, and the ratio of the total spectrum amplitude to the fundamental amplitude is recorded as the distortion degree characterization value of the current input voltage window; the method for obtaining the distortion degree characterization value of the historical input voltage window is the same as the method for obtaining the distortion degree characterization value of the current input voltage window.

4. The method for real-time monitoring of the operating status of a 220V DC system as described in claim 1, characterized in that, The method for obtaining the temperature characteristic value and performance characteristic value corresponding to the current moment includes: recording a sequence of temperature averages from a preset second number of historical temperature windows closest to the current temperature window as a historical temperature average sequence; obtaining a temperature average difference sequence, and using the result of negatively correlated mapping of the mean of the temperature average difference sequence as the temperature characteristic value corresponding to the current moment, wherein the b-th temperature average difference in the temperature average difference sequence is the absolute value of the difference between the temperature average of the current temperature window and the b-th temperature average in the historical temperature average sequence; recording a sequence of performance performance coefficients from all nearest historical moments as a historical performance performance coefficient sequence; obtaining a performance performance coefficient difference sequence, and using the result of negatively correlated mapping of the mean of the performance performance coefficient difference sequence as the performance characteristic value corresponding to the current moment, wherein the c-th performance performance coefficient difference in the performance performance coefficient difference sequence is the absolute value of the difference between the performance performance coefficient at the current moment and the c-th historical performance performance coefficient in the historical performance performance coefficient sequence.

5. The method for real-time monitoring of the operating status of a 220V DC system as described in claim 1, characterized in that, The method for obtaining the initial anomaly level index value at the current moment includes: obtaining the current feature coefficient based on the differences between the temperature feature value corresponding to the current moment and each temperature feature value in the historical temperature feature value sequence, and the differences between the performance feature value corresponding to the current moment and each performance feature value in the historical performance feature value sequence; obtaining the unprocessed comprehensive difference value corresponding to each historical temperature feature value in the historical temperature feature value sequence based on the differences between each historical temperature feature value in the historical temperature feature value sequence and other historical temperature feature values ​​excluding the corresponding historical temperature feature value; obtaining the unprocessed comprehensive difference value corresponding to each historical performance feature value in the historical performance feature value sequence based on the differences between each historical performance feature value in the historical performance feature value sequence and other historical performance feature values ​​excluding the corresponding historical performance feature value; recording the ratio between the mean of the unprocessed comprehensive difference values ​​corresponding to all historical temperature feature values ​​in the historical temperature feature value sequence and the mean of the unprocessed comprehensive difference values ​​corresponding to all historical performance feature values ​​in the historical performance feature value sequence as the nearest neighbor historical feature coefficient; and using the absolute value of the difference between the nearest neighbor historical feature coefficient and the current feature coefficient as the initial anomaly level index value at the current moment.

6. The method for real-time monitoring of the operating status of a 220V DC system as described in claim 5, characterized in that, The method for obtaining the current feature coefficient includes: obtaining a first difference sequence, wherein the d-th first difference in the first difference sequence is the absolute value of the difference between the temperature feature value corresponding to the current time and the d-th historical temperature feature value in the historical temperature feature value sequence, and the sum of all the first differences in the first difference sequence is taken as the first comprehensive difference; obtaining a second difference sequence, wherein the f-th second difference in the second difference sequence is the absolute value of the difference between the performance feature value corresponding to the current time and the f-th historical performance feature value in the historical performance feature value sequence, and the sum of all the second differences in the second difference sequence is taken as the second comprehensive difference, and the ratio of the first comprehensive difference to the second comprehensive difference is recorded as the current feature coefficient at the current time.

7. The method for real-time monitoring of the operating status of a 220V DC system as described in claim 6, characterized in that, The method for processing the comprehensive difference includes: for the h-th historical temperature feature value in the historical temperature feature value sequence, constructing a sequence of the remaining historical temperature feature values ​​excluding the h-th historical temperature feature value in the historical temperature feature value sequence as a feature subsequence, obtaining the difference sequence to be processed corresponding to the h-th historical temperature feature value, wherein the j-th difference to be processed in the difference sequence to be processed is the absolute value of the difference between the h-th historical temperature feature value and the j-th historical temperature feature value in the feature subsequence, and taking the sum of all differences to be processed in the difference sequence to be processed as the comprehensive difference to be processed corresponding to the h-th historical temperature feature value; the method for obtaining the comprehensive difference to be processed corresponding to the historical performance feature value in the historical performance feature value sequence is the same as the method for obtaining the comprehensive difference to be processed corresponding to the h-th historical temperature feature value.

8. The method for real-time monitoring of the operating status of a 220V DC system as described in claim 1, characterized in that, The method for monitoring the operating status of the rectifier module at the current moment based on the target anomaly index value at the current moment includes: determining whether the target anomaly index value is greater than a preset anomaly threshold; if so, issuing an alarm for an operational anomaly of the rectifier module.

Images