A method, device and system for detecting the voltage of a terminal

Abstract

The present invention relates to the technical field of electrical performance detection of electrical equipment, and specifically relates to a method, device and system for detecting the voltage of a terminal block, including: obtaining the voltage stability of each voltage data point according to the voltage data at both ends of the terminal block, obtaining the voltage-current change law characteristics according to the voltage drop and current at the same voltage data point, so as to obtain the voltage abnormality of each voltage data point, obtaining a correction coefficient according to the difference between the transient overvoltage dynamic change characteristics of the same voltage data point at both ends of the terminal block, so as to correct the voltage abnormality, and performing fault detection on the terminal block according to the corrected voltage abnormality, which helps to identify the influence of transient overvoltage on voltage fluctuation, can effectively distinguish the pseudo-abnormality of voltage from the real voltage fluctuation, improve the accuracy of fault detection of the terminal block, and thus improve the safety and stability of the operation of the power system.

Description

Technical Field

[0001] The present invention relates to the technical field of electrical performance detection of electrical equipment, and particularly to a method, device and system for detecting the voltage of a terminal block. Background Art

[0002] The terminal block is a key component for electrical connection, and its reliability and stability are crucial. In actual use, the terminal block may cause potential safety hazards due to poor contact, wear, temperature rise, etc. By detecting the voltage of the terminal block, the safety and stability of the electrical system can be ensured. The existing methods for detecting the voltage of the terminal block mainly rely on traditional voltmeter measurement. Although it can reflect the instantaneous state of the voltage, it cannot capture the transient changes and dynamic processes in real time, and the detection accuracy is relatively low. Therefore, a sensor is used to monitor the voltage of the terminal block in real time, and by analyzing and processing the change characteristics of the voltage data, high-precision and real-time voltage detection can be achieved.

[0003] In the prior art, in the voltage monitoring of the terminal block, a sensor is usually used to monitor the voltage across the terminal block in real time. By analyzing the abnormal fluctuations of the voltage data, it is possible to preliminarily judge whether there is an abnormality in the voltage, and thus infer the working state of the terminal block. However, in the actual application of the terminal block, the voltage detection is easily affected by factors such as load current, environmental factors (such as temperature, humidity), and electromagnetic interference, which may cause the generation of pseudo-abnormal fluctuations; in addition, the terminal block may also experience transient overvoltage phenomena during operation, which will cause rapid fluctuations in voltage and current. Simply analyzing the voltage data is not sufficient to accurately reflect the true voltage state, and thus it is impossible to accurately detect the faults of the terminal block. Summary of the Invention

[0004] In order to solve the technical problem of the low accuracy of the existing methods for detecting the faults of the terminal block, the object of the present invention is to provide a method, device and system for detecting the voltage of the terminal block, and the specific technical solutions adopted are as follows:

[0005] In the first aspect of the present invention, a method for detecting the voltage of a terminal block is provided, including:

[0006] Obtaining voltage data and current data across the terminal block;

[0007] Obtaining the voltage stability of each voltage data point according to the voltage data;

[0008] Obtaining the voltage-current change law characteristics according to the voltage drop across the same voltage data point at both ends of the terminal block in the voltage data and the current corresponding to the same voltage data point in the current data;

[0009] Based on the voltage-current change law characteristics and the voltage stability of each voltage data point, the voltage abnormality of each voltage data point is obtained;

[0010] Based on the differences between the transient overvoltage dynamic change characteristics of the same voltage data point at both ends of the terminal block, the transient overvoltage manifestation degree of each voltage data point is obtained;

[0011] The voltage abnormality is corrected according to the transient overvoltage manifestation degree to obtain the target voltage abnormality;

[0012] Based on the target voltage abnormality of each voltage data point, the terminal block is subjected to fault detection.

[0013] In an exemplary embodiment, obtaining the voltage stability of each voltage data point according to the voltage data includes:

[0014] The voltage data at both ends of the terminal block are segmented according to the same segmentation rule to obtain a plurality of voltage data segments corresponding to each end of the terminal block;

[0015] The difference distance between the voltage data segment and the reference voltage data segment is obtained, and the difference in the voltage change degree between each voltage data point in the voltage data segment and the voltage data point at the corresponding position in the reference voltage data segment is obtained;

[0016] Based on the difference distance and the difference in the voltage change degree, the trend deviation degree of the voltage data point is obtained; the trend deviation degree is proportional to the difference distance and the difference in the voltage change degree;

[0017] Based on the trend deviation degrees of the corresponding voltage data points at both ends of the terminal block, the voltage stability of the voltage data point is obtained; the voltage stability is inversely proportional to the trend deviation degrees of the corresponding voltage data points at both ends of the terminal block.

[0018] In an exemplary embodiment, obtaining the voltage-current change law characteristics according to the voltage drop of the same voltage data point at both ends of the terminal block in the voltage data and the current corresponding to the same voltage data point in the current data includes:

[0019] The ratio of the voltage drop corresponding to each voltage data point to the current value corresponding to the voltage data point is obtained as the voltage-current change relationship of the corresponding voltage data point; the voltage drop is the difference in the voltage values of the same voltage data point at both ends of the terminal block;

[0020] Based on the voltage-current change relationships of any two adjacent voltage data points, the voltage-current change law characteristics are obtained.

[0021] In an exemplary embodiment, according to the voltage-current change relationship between any two adjacent voltage data points, a voltage-current change law feature is obtained, including:

[0022] Calculate the difference in the voltage-current change relationship between any two adjacent voltage data points;

[0023] Fuse the differences in the voltage-current change relationships between any two adjacent voltage data points to obtain an overall difference in the voltage-current change relationship;

[0024] According to the overall difference in the voltage-current change relationship, a voltage-current change law feature is obtained, and the voltage-current change law feature is inversely proportional to the overall difference in the voltage-current change relationship.

[0025] In an exemplary embodiment, according to the voltage-current change law feature and the voltage stability of each voltage data point, the voltage abnormality of each voltage data point is obtained, including:

[0026] Obtain the difference between the voltage-current change law feature and a preset reference voltage-current change law feature to obtain a voltage-current change law feature difference;

[0027] According to the voltage-current change law feature difference and the voltage stability of each voltage data point, the voltage abnormality of each voltage data point is obtained; the voltage abnormality is directly proportional to the voltage-current change law feature difference and inversely proportional to the voltage stability.

[0028] In an exemplary embodiment, according to the difference between the transient overvoltage dynamic change features of the same voltage data point at both ends of the wiring terminal, the transient overvoltage manifestation degree of each voltage data point is obtained, including:

[0029] According to the voltage range of the voltage data segment where each voltage data point is located and the voltage change degree of each voltage data point, the transient overvoltage dynamic change feature of each voltage data point is obtained; the transient overvoltage dynamic change feature is directly proportional to the voltage range and the voltage change degree;

[0030] Obtain the difference between the transient overvoltage dynamic change features of the same voltage data point at both ends of the wiring terminal;

[0031] According to the difference between the transient overvoltage dynamic change features, the transient overvoltage manifestation degree is obtained; the transient overvoltage manifestation degree is inversely proportional to the difference between the transient overvoltage dynamic change features.

[0032] In an exemplary embodiment, according to the transient overvoltage manifestation degree, the voltage abnormality is corrected to obtain a target voltage abnormality, including:

[0033] The correction factor for each voltage data point is obtained based on the transient overvoltage manifestation degree of each voltage data point, and the correction factor is inversely proportional to the transient overvoltage manifestation degree;

[0034] Multiply the correction factor of each voltage data point by the voltage abnormality of each voltage data point, and the product obtained is the target voltage abnormality of each voltage data point.

[0035] In an exemplary embodiment, according to the target voltage abnormality of each voltage data point, fault detection is performed on the terminal block, including:

[0036] Compare the target voltage abnormality of each voltage data point with a preset voltage abnormality threshold;

[0037] If there are a preset number of target voltage abnormalities greater than or equal to the preset voltage abnormality threshold, it is determined that the terminal block has a fault.

[0038] In a second aspect of the present invention, a terminal block voltage detection device is provided. The terminal block voltage detection device includes a unit for executing the above terminal block voltage detection method.

[0039] In a third aspect of the present invention, a terminal block voltage detection system is provided, including: a memory and a processor; the memory is connected to the processor; the memory is used to store program instructions; the processor is used to implement the above terminal block voltage detection method when the program instructions are executed.

[0040] The present invention has the following beneficial effects: The present invention first obtains the voltage stability of each voltage data point, and then obtains the voltage-current change law characteristics according to the voltage drop of the same voltage data point at both ends of the terminal block and the current corresponding to the same voltage data point. Combining the relationship between the current of the terminal block and the voltage drops on both sides can effectively eliminate the influence of interference factors on the voltage detection result and ensure the reliability of the data; thus, according to the voltage-current change law characteristics and the voltage stability of each voltage data point, the voltage abnormality of each voltage data point is obtained, and according to the difference between the transient overvoltage dynamic change characteristics of the same voltage data point at both ends of the terminal block, the transient overvoltage manifestation degree of each voltage data point is obtained. The voltage abnormality is corrected according to the transient overvoltage manifestation degree to obtain the target voltage abnormality, which helps to identify the influence of transient overvoltage on voltage fluctuation, can effectively distinguish the pseudo-abnormality of voltage from the real voltage fluctuation, and thus perform fault detection on the terminal block according to the target voltage abnormality of each voltage data point, which can improve the accuracy of fault detection of the terminal block, thereby improving the safety and stability of the operation of the power system. Description of the Drawings

[0041] Figure 1It is a flowchart of a method for detecting the voltage of a terminal provided by an embodiment of the present invention;

[0042] Figure 2 It is a normal sine wave voltage waveform diagram provided by an embodiment of the present invention;

[0043] Figure 3 It is a sine wave voltage waveform diagram with a spike voltage signal provided by an embodiment of the present invention;

[0044] Figure 4 It is a flowchart for obtaining the voltage stability provided by an embodiment of the present invention;

[0045] Figure 5 It is a flowchart for obtaining the characteristics of the voltage and current change law provided by an embodiment of the present invention;

[0046] Figure 6 It is a flowchart of step S32 provided by an embodiment of the present invention;

[0047] Figure 7 It is a flowchart for obtaining the voltage abnormality provided by an embodiment of the present invention;

[0048] Figure 8 It is a flowchart for obtaining the transient overvoltage manifestation degree provided by an embodiment of the present invention;

[0049] Figure 9 It is a flowchart for obtaining the target voltage abnormality provided by an embodiment of the present invention;

[0050] Figure 10 It is a flowchart for performing fault detection on the terminal provided by an embodiment of the present invention. Detailed implementation manners

[0051] In order to further elaborate on the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the following, in conjunction with the accompanying drawings and preferred embodiments, details the specific implementation manners, structures, features, and effects of the present invention. In the following description, different "one embodiment" or "another embodiment" do not necessarily refer to the same embodiment. In addition, the specific features, structures, or characteristics in one or more embodiments can be combined in any suitable form.

[0052] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which the present invention belongs.

[0053] This embodiment provides a method for detecting the voltage of a terminal block for fault detection of the terminal block. First, a detection device needs to be constructed, including a voltage sensor and a current sensor. The number of voltage sensors is 2. One voltage sensor is set at one end of the terminal block, and the other voltage sensor is set at the other end of the terminal block for detecting the voltages at both ends of the terminal block respectively. According to the current characteristics, the currents at both ends of the terminal block are the same. Therefore, only one current sensor is needed, which is set at one end of the terminal block for detecting the current flowing through the terminal block.

[0054] In this embodiment, the voltage connected to the terminal block is an alternating voltage, that is, the output detection voltage is an alternating voltage, namely a sine wave voltage. Correspondingly, the voltage sensor and the current sensor are an alternating voltage sensor and an alternating current sensor respectively. The specific selection of the voltage sensor and the current sensor is set according to actual needs and is not limited in this embodiment.

[0055] It should be understood that the terminal block can be detected during actual application or during the preliminary experiment stage. If it is detected during the preliminary experiment stage, then both ends of the terminal block are connected to an alternating voltage source, and the alternating voltage source is used to output a detection voltage to the terminal block. The implementer can make a choice according to the actual situation, which is not limited in this embodiment.

[0056] The voltage sensor and the current sensor output voltage signals and current signals in real time. In an exemplary embodiment, the analog signal can be converted into a digital signal by an analog-to-digital converter (ADC, Analog to digital converter) and input into a data processing system for further digital signal processing. The data processing process executed in the data processing system is a method for detecting the voltage of a terminal block provided by this embodiment.

[0057] The method for detecting the voltage of a terminal block provided by this embodiment can detect the voltage of the terminal block, which helps to timely discover voltage abnormalities, ensure the safe and stable operation of the terminal block, and avoid potential faults and damages. During the voltage detection process, the real-time monitored voltage data is analyzed, and potential voltage problems of the terminal block are identified through the change trend of the voltage data, so as to realize the fault detection of the terminal block.

[0058] As Figure 1 shown, the method for detecting the voltage of a terminal block provided by this embodiment includes:

[0059] Step S1: Obtain the voltage data and current data at both ends of the terminal block.

[0060] The data sampling frequencies of the voltage sensor and the current sensor are the same. Moreover, the voltage sensor and the current sensor collect data synchronously, so that at a certain sampling moment, the voltage at one end of the terminal block and the voltage at the other end of the terminal block, as well as the current flowing through the terminal block, can be obtained respectively.

[0061] The voltage data is collected by two voltage sensors respectively arranged at both ends of the terminal block, including the voltage data at one end of the terminal block and the voltage data at the other end of the terminal block. The current data is collected by the current sensor arranged at the terminal block.

[0062] In an exemplary embodiment, the collected voltage and current data can also be preprocessed, such as through filtering, amplification, denoising, etc., to ensure the accuracy and reliability of the measurement results.

[0063] Since the voltage is an alternating voltage, during normal operation of the terminal block, the voltage remains stable, without obvious sudden changes or abnormal fluctuations, and shows periodic changes. Therefore, the normal voltage data should be sinusoidal voltage data, and the waveform is as Figure 2 shown. It is composed of multiple sine waves, and each sine wave is a cycle. Correspondingly, the current data is also a sine wave. When there is an instantaneous spike in the voltage, there will be a spike voltage signal in the sine wave voltage waveform curve, as Figure 3 shown.

[0064] It should be understood that the detection duration of the terminal block is set according to actual needs. In order to ensure the detection accuracy, it can be set appropriately longer. Therefore, the voltage data and the current data include multiple sine wave cycles.

[0065] The voltage data at both ends of the terminal block is time-series data, including the voltages at multiple sampling moments at both ends of the terminal block; the current data of the terminal block is also time-series data, including the currents at multiple sampling moments of the terminal block.

[0066] Step S2: Obtain the voltage stability of each voltage data point according to the voltage data.

[0067] Through the voltage data of the terminal block, the voltage stability of each voltage data point in the voltage data can be obtained. In an exemplary embodiment, as Figure 4 shown, the process of obtaining the voltage stability includes:

[0068] Step S21: Segment the voltage data at both ends of the terminal block according to the same segmentation rule to obtain multiple voltage data segments corresponding to each end of the terminal block.

[0069] In an exemplary embodiment, since the voltage data is waveform data with periodicity, then segment the voltage data according to the waveform cycle.

[0070] In order to improve the accuracy of data processing, in this embodiment, the voltage data is composed of voltage sine waves of several complete cycles; the current data is composed of current sine waves of several complete cycles. If the data at the start and end positions in the initially acquired voltage data and current data are sine waves of incomplete cycles, then these sine waves of incomplete cycles need to be cut off and discarded, so as to obtain voltage data composed of voltage sine waves of several complete cycles and current data composed of current sine waves of several complete cycles. Alternatively, during data acquisition, start collecting from the starting moment of a certain cycle and then end collecting at the ending moment of a certain cycle to obtain data information of multiple complete cycles.

[0071] For the convenience of description, the voltage data at one end of the terminal is defined as the first voltage data, and the voltage data at the other end of the terminal is defined as the second voltage data.

[0072] Segment the first voltage data according to the voltage cycle to obtain multiple voltage data segments corresponding to the first voltage data. Among them, the voltage cycle is a known value. As other implementation manners, Fourier transform can also be used to convert the voltage data from the time domain to the frequency domain. The main frequency component in the spectrum corresponds to the main periodic change of the voltage data, and the period of the voltage data is obtained. Similarly, segment the second voltage data according to the voltage cycle to obtain multiple voltage data segments corresponding to the second voltage data. Since the periods of the voltage data and the current data are the same and there is a corresponding relationship, segment the current data according to the voltage cycle to obtain multiple current data segments corresponding to the current data. Then, each voltage data segment is a voltage sine wave of a complete cycle, and each current data segment is a current sine wave of a complete cycle.

[0073] Since there is a corresponding relationship in time sequence between the first voltage data and the second voltage data, then there is also a one-to-one corresponding relationship between the voltage data segments corresponding to the first voltage data and the voltage data segments corresponding to the second voltage data. That is, the i-th voltage data segment of the first voltage data and the i-th voltage data segment of the second voltage data are corresponding voltage data segments. Moreover, the number of voltage data points included in the i-th voltage data segment of the first voltage data and the i-th voltage data segment of the second voltage data is the same, and the voltage data points at the same position have a corresponding relationship, that is, the q-th voltage data point in the i-th voltage data segment of the first voltage data and the q-th voltage data point in the i-th voltage data segment of the second voltage data are a pair of voltage data points with a corresponding relationship.

[0074] Moreover, the i-th voltage data segment of the first voltage data corresponds to the i-th current data segment of the current data. Moreover, the number of data points included in the i-th voltage data segment of the first voltage data is the same as that of the i-th current data segment of the current data, and the data points at the same positions have a corresponding relationship, that is, the q-th voltage data point in the i-th voltage data segment of the first voltage data corresponds to the q-th current data point in the i-th current data segment of the current data.

[0075] Step S22: Obtain the difference distance between the voltage data segment and the reference voltage data segment, and obtain the difference in the degree of voltage change between each voltage data point in the voltage data segment and the voltage data point at the corresponding position in the reference voltage data segment.

[0076] To facilitate obtaining the differences between each voltage data segment and the normal situation, in this embodiment, a reference voltage data segment is preset. The reference voltage data segment represents the voltage data segment with normal voltage, that is, in the current scenario, the wiring terminal belongs to the voltage sine wave data of a complete cycle in a normal voltage state, that is, a complete cycle of voltage sine wave data collected under the condition of ensuring normal voltage.

[0077] In an exemplary embodiment, the similarity between any two voltage data segments can be obtained, and the calculation formula is as follows:

[0078] ;

[0079] Wherein, represents the DTW distance between the i-th voltage data segment and the j-th voltage data segment; represents the voltage value sequence of the i-th voltage data segment; represents the voltage value sequence of the j-th voltage data segment. represents the DTW distance between the i-th voltage data segment and the j-th voltage data segment, representing the similarity measure between the waveforms of these two voltage data segments. The larger this value is, the smaller the similarity between the waveforms of these two voltage data segments.

[0080] According to the DTW distance between any two voltage data segments, the voltage data segments are clustered using the K-means algorithm, where K in the K-means algorithm is 2, that is, two clusters are obtained. The larger the DTW distance, the less likely it is to be clustered into one category.

[0081] Since voltage abnormal fluctuations are rare cases, while voltage stability is the performance when the terminal works normally, so find the cluster with a larger number of voltage data segments containing voltage data from the two clusters. This cluster represents the voltage data segments under normal voltage conditions and is the normal cluster. Then, calculate the average value of the voltage data points at each position in the voltage data segments of the normal cluster, and form a voltage data waveform based on the average values of the voltage data points at each position. This voltage data waveform is used as the reference voltage data segment.

[0082] For any voltage data segment, the greater the difference distance between it and the reference voltage data segment, the more abnormal the voltage data segment indicates. Obtain the difference distance between this voltage data segment and the reference voltage data segment. The difference distance can specifically be the DTW distance. The larger the DTW distance, the greater the difference between this voltage data segment and the reference voltage data segment. The DTW algorithm is an existing algorithm and will not be elaborated here. As other implementation manners, it is also possible to obtain the similarity between this voltage data segment and the reference voltage data segment, such as cosine similarity, Pearson correlation coefficient, etc., and then perform negative correlation to obtain the difference distance.

[0083] Then, obtain the difference in the voltage change degree between each voltage data point in this voltage data segment and the voltage data point at the corresponding position in the reference voltage data segment. The voltage change degree is the speed of voltage change of the voltage data point. In an exemplary embodiment, the voltage change degree is characterized by the slope at the corresponding voltage data point in the voltage curve corresponding to the voltage data segment. The greater the slope, the greater the voltage change degree. Then, obtain the difference in the slope between each voltage data point in this voltage data segment and the voltage data point at the corresponding position in the reference voltage data segment. The greater the slope difference, the greater the difference between this voltage data segment and the reference voltage data segment, and the more abnormal this voltage data segment is.

[0084] Step S23: Obtain the trend deviation degree of the voltage data point according to the difference distance and the difference in the voltage change degree.

[0085] The trend deviation degree of the voltage data point characterizes the deviation degree between the voltage data point and the normal data, that is, the abnormal degree of the voltage data point. Through the above analysis, it can be seen that the greater the difference distance, the greater the trend deviation degree of the voltage data point, and the greater the difference in the voltage change degree, the greater the trend deviation degree of the voltage data point. Therefore, the trend deviation degree is proportional to the difference distance and the difference in the voltage change degree.

[0086] In an exemplary embodiment, a calculation formula for the trend deviation degree is given as follows:

[0087] ;

[0088] Wherein, represents the The trend deviation degree at a voltage data point; It represents the difference distance between the i-th voltage data segment in the first voltage data and the reference voltage data segment, representing the change similarity. The larger this value is, the smaller the similarity, and the greater the deviation from the voltage change in the normal working condition; It represents the slope at the th voltage data point in the i-th voltage data segment of the first voltage data; slope at the

[0089] It represents the th voltage data point in the i-th voltage data segment of the first voltage data; The slope difference between the slope at the

[0090] th voltage data point in the reference voltage data segment.

[0091] Therefore, the trend deviation degree represents the degree of consistency of the change trend. The larger the trend deviation degree, the more inconsistent the change trend, and the more abnormal the corresponding voltage data point.

[0092] Step S24: Obtain the voltage stability of the voltage data point according to the trend deviation degree of the corresponding voltage data points at both ends of the terminal.

[0093] During the actual detection of the voltage data of the terminal, it is easily affected by the environment and other factors, manifested as abnormal waveforms in the collected voltage data, and as a larger trend deviation degree in the above analysis. To distinguish the influence of interference factors on the voltage, by analyzing the dynamic changes of the current and voltage on both sides of the terminal, the interference is excluded; at the same time, during the operation of the terminal, there will be a phenomenon of transient overvoltage, which will affect both the current and voltage of the terminal. It is necessary to further analyze the current and voltage changes caused by the transient overvoltage, so as to make the voltage detection result more accurate.

[0094] When current passes through the terminal, the terminal serves as an electrical connection point and usually carries the current flow. Resistance is generated between its material and the contact point, and a voltage difference is formed at both ends. If there is an abnormal voltage phenomenon in the terminal, the voltages at both ends should show an abnormal change trend simultaneously. By observing the change trend of the voltages on both sides of the terminal, the voltage stability can be obtained. Therefore, based on the trend deviation degree of the corresponding voltage data points at both ends of the terminal, the voltage stability of the voltage data points is obtained, and the voltage stability is inversely proportional to the trend deviation degree of the corresponding voltage data points at both ends of the terminal.

[0095] In an exemplary embodiment, a calculation formula for voltage stability is given as follows:

[0096] ;

[0097] Wherein, represents the voltage stability of the th voltage data point in the i-th voltage data segment; represents the trend deviation degree at the th voltage data point in the i-th voltage data segment of the second voltage data. represents the negative correlation normalization of , and represents the exponential function with the natural constant e as the base.

[0098] represents the overall situation of the trend deviation degree of the th voltage data point in the i-th voltage data segment at both ends of the terminal. The larger this value is, the smaller the voltage stability of the th voltage data point in the i-th voltage data segment.

[0099] Step S3: According to the voltage drop of the same voltage data point at both ends of the terminal in the voltage data and the current corresponding to the same voltage data point in the current data, obtain the voltage-current change law characteristics.

[0100] Transient overvoltage is a transient voltage fluctuation caused by a rapidly changing current, usually resulting from electrical equipment switching, electromagnetic interference, and load changes. When the current fluctuates significantly, the terminal may be affected and the voltage difference generation may be aggravated. To analyze the specific changes brought by transient overvoltage, the voltage drop needs to be obtained. The voltage drop refers to the difference in the voltage values of the same voltage data point at both ends of the terminal, and the difference is specifically the absolute value of the difference.

[0101] In an exemplary embodiment, the following calculation formula is used to obtain the voltage drop:

[0102] ;

[0103] Wherein, represents the voltage drop of the th voltage data point in the i-th voltage data segment; represents one side of the terminal, that is, the voltage value of the th voltage data point in the i-th voltage data segment of the first voltage data, represents the other side of the terminal, that is, the voltage value of the th voltage data point in the i-th voltage data segment of the second voltage data; represents the voltage difference between the th voltage data points in the i-th voltage data segment on both sides of the terminal, that is, the voltage drop.

[0104] In an exemplary embodiment, as Figure 5 shown, a specific obtaining process of the voltage-current change law characteristics is given as follows:

[0105] Step S31: Obtain the ratio of the voltage drop corresponding to each voltage data point to the current value corresponding to the voltage data point as the voltage-current change relationship corresponding to the voltage data point.

[0106] In an exemplary embodiment, the calculation formula of the voltage-current change relationship is as follows:

[0107] ;

[0108] Wherein, represents the voltage-current change relationship of the th voltage data point in the i-th voltage data segment, represents the current value of the th current data point in the i-th current data segment. Among them, the th current data point in the i-th current data segment corresponds to the th voltage data point in the i-th voltage data segment, and can be understood as the same data point.

[0109] Then, the voltage-current change relationship can be characterized as the relevant characteristics of the resistance of the terminal corresponding to the th voltage data point in the i-th voltage data segment.

[0110] Step S32: Obtain the voltage-current change law characteristics according to the voltage-current change relationships of any two adjacent voltage data points.

[0111] In an exemplary embodiment, as Figure 6 shown, a specific implementation process of Step S32 is given as follows, including:

[0112] Step S321: Calculate the difference in the voltage-current change relationship between any two adjacent voltage data points. The difference here is the absolute value of the difference in the voltage-current change relationship between any two adjacent voltage data points.

[0113] Step S322: Integrate the differences in the voltage-current change relationship between any two adjacent voltage data points to obtain the overall difference in the voltage-current change relationship. The specific integration method here is to take the average.

[0114] Step S323: Obtain the voltage-current change law characteristics based on the overall difference in the voltage-current change relationship.

[0115] The overall difference in the voltage-current change relationship characterizes the consistency of the change relationship between voltage and current. The greater the overall difference in the voltage-current change relationship, the more inconsistent the change between voltage and current. Therefore, the lower the voltage-current change law characteristics. Thus, the voltage-current change law characteristics are inversely proportional to the overall difference in the voltage-current change relationship.

[0116] In an exemplary embodiment, the following gives the calculation formula for the voltage-current change law characteristics:

[0117] ;

[0118] ;

[0119] ;

[0120] where represents the voltage drop of the th voltage data point in the i-th voltage data segment, represents one side of the terminal, that is, the voltage value of the th voltage data point in the i-th voltage data segment of the first voltage data, represents the other side of the terminal, that is, the voltage value of the th voltage data point in the i-th voltage data segment of the second voltage data.

[0121] represents the voltage-current change relationship of the th voltage data point in the i-th voltage data segment, represents the current of the th current data point in the i-th current data segment, where the th current data point in the i-th current data segment corresponds to the th voltage data point in the i-th voltage data segment and can be understood as the same data point.

[0122] represents the The difference between the voltage-current variation relationship of the j-th voltage data point and the voltage-current variation relationship of the j-th voltage data point in the i-th voltage data segment. represents the number of voltage data points in the i-th voltage data segment.

[0123] represents the average value of the differences between the voltage-current variation relationships of any two adjacent voltage data points in the i-th voltage data segment, which is the overall difference in the voltage-current variation relationship. The smaller the overall difference in the voltage-current variation relationship, the greater the consistency in the change trends of voltage and current.

[0124] represents the characteristic of the voltage-current variation law in the i-th voltage data segment, that is, the degree of consistency in the change trends of voltage and current.

[0125] Step S4: Obtain the voltage abnormality of each voltage data point based on the characteristic of the voltage-current variation law and the voltage stability of each voltage data point.

[0126] According to the change law of the terminal current and the voltage at both ends, combined with the voltage stability at both ends, the influence of most interference factors can be excluded. When the corresponding change law remains unchanged, the voltage detection result of the terminal is normal at this time; if it changes, there is a problem with the voltage data at this time. Then, obtain the voltage abnormality of each voltage data point based on the characteristic of the voltage-current variation law and the voltage stability of each voltage data point.

[0127] In an exemplary embodiment, as Figure 7 shown, a specific obtaining process of voltage abnormality is given as follows, including:

[0128] Step S41: Obtain the difference between the characteristic of the voltage-current variation law and the preset reference voltage-current variation law characteristic to obtain the difference in the characteristic of the voltage-current variation law.

[0129] Preset a reference voltage-current variation law characteristic. The purpose of this preset reference voltage-current variation law characteristic is to compare it with the voltage-current variation law characteristic obtained in step 3 to obtain the difference between the two. The greater the difference, the greater the abnormality. This preset reference voltage-current variation law characteristic can be characterized as the voltage-current variation law characteristic under normal voltage and current conditions in general. Therefore, this preset reference voltage-current variation law characteristic can be a pre-set known data. As other implementation manners, it can also be the average value of the voltage-current variation law characteristics of all voltage data segments, and the average value is used to characterize the overall situation of the voltage-current variation law characteristic.

[0130] ​Obtain the difference between the characteristics of the voltage and current variation law and the characteristics of the preset reference voltage and current variation law, and obtain the difference in the characteristics of the voltage and current variation law. The greater the difference in the characteristics of the voltage and current variation law, the more abnormal the characteristics of the voltage and current variation law.

[0131] Step S42: Obtain the voltage abnormality of each voltage data point according to the difference in the characteristics of the voltage and current variation law and the voltage stability of each voltage data point.

[0132] The voltage abnormality characterizes the voltage abnormal situation, that is, the abnormal situation. Therefore, the greater the difference in the characteristics of the voltage and current variation law, the greater the voltage abnormality, and the smaller the voltage stability, the greater the voltage abnormality. Then, the voltage abnormality is proportional to the difference in the characteristics of the voltage and current variation law and inversely proportional to the voltage stability.

[0133] In an exemplary embodiment, the following gives the calculation formula for voltage abnormality:

[0134] ;

[0135] Wherein, represents the voltage abnormality of the th voltage data point in the i-th voltage data segment; represents the characteristics of the preset reference voltage and current variation law.

[0136] Step S5: Obtain the transient overvoltage manifestation degree of each voltage data point according to the difference between the transient overvoltage dynamic change characteristics of the same voltage data point at both ends of the terminal block.

[0137] In an exemplary embodiment, as Figure 8 shown, the following gives a specific acquisition process of the transient overvoltage manifestation degree, including:

[0138] Step S51: Obtain the transient overvoltage dynamic change characteristics of each voltage data point according to the voltage range of the voltage data segment where each voltage data point is located and the degree of voltage change of each voltage data point.

[0139] At the moment when a transient overvoltage occurs, the voltage drop across the terminal usually increases rapidly because the instantaneous increase in current causes a greater voltage loss across the resistance and contact resistance of the terminal. This is manifested as a spike in the voltage drop across the terminal during the duration of the overvoltage. As the current returns to the normal value, the voltage drop gradually returns to the normal level. After a transient overvoltage, the voltage drop across the terminal gradually returns to the normal level as the current decays. In the case of a transient overvoltage, there is a spike phenomenon in both the current and the voltage drop simultaneously. By analyzing the data changes, the dynamic change characteristics of the transient overvoltage of the voltage data can be obtained. According to the dynamic change characteristics of the transient overvoltage of the terminal voltage, during the voltage detection process, this transient change is temporary and recoverable, and the detected voltage change is within the normal range. Therefore, based on the dynamic characteristics of the transient overvoltage, the true detection state of the voltage data can be obtained.

[0140] Obtain the voltage range of each voltage data segment where the voltage data points are located. The voltage range is the difference between the maximum voltage value and the minimum voltage value in the corresponding voltage data segment.

[0141] Based on the voltage range of each voltage data segment where the voltage data points are located and the degree of voltage change of each voltage data point, the dynamic change characteristics of the transient overvoltage of each voltage data point are obtained. The dynamic change characteristics of the transient overvoltage characterize the degree of change of the transient overvoltage. Then, the greater the voltage range, the greater the dynamic change characteristics of the transient overvoltage, and the greater the degree of voltage change, the greater the dynamic change characteristics of the transient overvoltage. Therefore, the dynamic change characteristics of the transient overvoltage are proportional to the voltage range and the degree of voltage change.

[0142] In an exemplary embodiment, a specific calculation formula for the dynamic change characteristics of the transient overvoltage is given as follows:

[0143] ;

[0144] Where, represents one end of the terminal, that is, the dynamic change characteristics of the transient overvoltage of the th voltage data point in the i-th voltage data segment of the first voltage data; represents the difference between the maximum voltage value and the minimum voltage value in the i-th voltage data segment of the first voltage data, that is, the voltage range.

[0145] The larger the , the more in line with the characteristics of the transient overvoltage with a sharp increase instantaneously. The larger the , the greater the possibility that the th voltage data point in the i-th voltage data segment of the first voltage data is a spike caused by the transient voltage.

[0146] Step S52: Obtain the difference between the transient overvoltage dynamic change characteristics of the same voltage data points at both ends of the terminal block.

[0147] The difference between the transient overvoltage dynamic change characteristics of the same voltage data points at both ends of the terminal block is specifically the absolute value of the difference.

[0148] Step S53: Obtain the transient overvoltage manifestation degree based on the difference between the transient overvoltage dynamic change characteristics.

[0149] According to the dynamic change characteristics of the current and voltage of the terminal block, if the current and voltage conform to the dynamic change trend caused by the transient overvoltage phenomenon, it indicates that the voltage data showing abnormal fluctuations is a normal change.

[0150] Then, the smaller the difference between the transient overvoltage dynamic change characteristics, the more it belongs to the normal transient overvoltage phenomenon, and the higher the transient overvoltage manifestation degree. Therefore, the transient overvoltage manifestation degree is inversely proportional to the difference between the transient overvoltage dynamic change characteristics.

[0151] In an exemplary embodiment, a specific calculation formula for the transient overvoltage manifestation degree is given as follows:

[0152] ;

[0153] Wherein, represents the transient overvoltage manifestation degree of the th voltage data point in the i-th voltage data segment; represents the transient overvoltage dynamic change characteristic of the th voltage data point in the i-th voltage data segment at the other end of the terminal block, that is, in the second voltage data.

[0154] represents the difference between the transient overvoltage dynamic change characteristics of the th voltage data point in the i-th voltage data segment at both ends of the terminal block.

[0155] Step S6: Correct the voltage abnormality according to the transient overvoltage manifestation degree to obtain the target voltage abnormality.

[0156] For the voltage data showing abnormal fluctuations at the terminal block, if a transient overvoltage occurs, it is necessary to adjust the voltage abnormality of the corresponding voltage data point to obtain a more accurate voltage detection result. Moreover, the more it belongs to the normal transient overvoltage situation, the more necessary it is to eliminate the influence caused by the transient overvoltage.

[0157] In an exemplary embodiment, as Figure 9 shown, a specific obtaining process of the target voltage abnormality is given as follows, including:

[0158] Step S61: Obtain the correction factor for each voltage data point according to the transient overvoltage manifestation degree of each voltage data point. Among them, the correction factor is inversely proportional to the transient overvoltage manifestation degree.

[0159] Step S62: Multiply the correction factor of each voltage data point by the voltage abnormality of each voltage data point, and the product obtained is the target voltage abnormality of each voltage data point.

[0160] In an exemplary embodiment, a specific calculation formula for the target voltage abnormality is given as follows:

[0161] ;

[0162] Wherein, represents the target voltage abnormality of the th voltage data point in the i-th voltage data segment. is the correction factor of the th voltage data point in the i-th voltage data segment.

[0163] By adopting the above process, the target voltage abnormality of each voltage data point in each voltage data segment is obtained. The target voltage abnormality is the voltage detection result after removing the interference of transient overvoltage.

[0164] Step S7: Perform fault detection on the wiring terminal according to the target voltage abnormality of each voltage data point.

[0165] By analyzing the voltage abnormality situation of the wiring terminal that may be caused by transient overvoltage, generating a short voltage spike or drop, the corrected voltage abnormality is obtained.

[0166] In an exemplary embodiment, as Figure 10 shown, a specific acquisition process for performing fault detection on the wiring terminal is given as follows, including:

[0167] Step S71: Compare the target voltage abnormality of each voltage data point with the preset voltage abnormality threshold;

[0168] Step S72: If there are a preset number of target voltage abnormalities greater than or equal to the preset voltage abnormality threshold, it is determined that the wiring terminal has a fault.

[0169] A preset voltage anomaly threshold is set, which is used to compare with the target voltage anomaly of each voltage data point. Among them, for the target voltage anomaly greater than this preset voltage anomaly threshold, the influence of transient overvoltage is excluded, indicating that the actual voltage fluctuation of the corresponding voltage data point exceeds the normal range, there is an abnormality in the detection result, and there may be problems such as faults in the terminal block. The numerical range of this preset voltage anomaly threshold is 0 - 1, and the specific value is determined according to actual judgment needs. In this embodiment, 0.7 is taken as an example.

[0170] Compare the target voltage anomaly of each voltage data point with the preset voltage anomaly threshold. If there are a preset number of target voltage anomalies greater than or equal to the preset voltage anomaly threshold, it is determined that there is a fault in the terminal block. The preset number is set according to actual needs, which can be 1, or a positive number greater than 1, such as 5. Then, if there are a preset number of target voltage anomalies greater than or equal to the preset voltage anomaly threshold, it is determined that there is a fault in the terminal block, and immediate repair is required to ensure the safe and stable operation of the electrical system. Subsequently, an alarm signal can be output to promptly remind the staff to pay attention.

[0171] This embodiment also provides a terminal block voltage detection device, which includes a unit for executing the above terminal block voltage detection method. Each unit can be a software unit corresponding to each method step, or a hardware circuit for executing each method step. This embodiment does not make a limitation.

[0172] This embodiment also provides a terminal block voltage detection system, including: a memory and a processor; the memory is connected to the processor, and the memory is used to store program instructions; the processor is used to implement the steps in the above terminal block voltage detection method embodiment when the program instructions are executed.

[0173] In an exemplary embodiment, the present invention provides a computer-readable storage medium storing a computer program, which implements the steps in the above terminal block voltage detection method embodiment when executed by a processor.

[0174] It should be noted that: the above sequence of the embodiments of the present invention is only for description and does not represent the superiority or inferiority of the embodiments. The processes depicted in the drawings do not necessarily require the specific order or continuous order shown to achieve the desired result. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0175] Each embodiment in this specification is described in a progressive manner, and the same or similar parts between each embodiment can be referred to each other. The key point of each embodiment is to illustrate the differences from other embodiments.

Claims

1. A method for detecting voltage at a terminal, characterized in that: include: Obtain voltage data and current data at both ends of the terminal; According to the voltage data, obtaining the voltage stability of each voltage data point; Obtaining voltage and current variation regularity characteristics according to a voltage drop of a same voltage data point at both ends of the wiring terminals in the voltage data and a current corresponding to the same voltage data point in the current data; According to the voltage and current variation law characteristics and the voltage stability of each voltage data point, the voltage anomaly of each voltage data point is obtained; According to the difference between the transient overvoltage dynamic change characteristics of the same voltage data point at both ends of the wiring terminal, the transient overvoltage performance degree of each voltage data point is obtained; Correcting the voltage anomaly according to the transient overvoltage performance to obtain a target voltage anomaly; performing fault detection on the wiring terminal according to target voltage anomalies of each voltage data point; According to the voltage and current variation law characteristics and the voltage stability of each voltage data point, the voltage anomaly of each voltage data point is obtained, including: Obtaining a difference between the voltage and current variation law characteristic and a preset reference voltage and current variation law characteristic to obtain a voltage and current variation law characteristic difference; According to the characteristic difference of the voltage and current variation law and the voltage stability of each voltage data point, the voltage anomaly of each voltage data point is obtained; the voltage anomaly is proportional to the characteristic difference of the voltage and current variation law and inversely proportional to the voltage stability; The calculation formula of voltage anomaly is given as follows: ； in, Indicates the first voltage data segment Voltage anomaly of each voltage data point; Indicates the characteristics of the change rules of the preset reference voltage and current; According to the difference between the transient overvoltage dynamic change characteristics of the same voltage data point at both ends of the terminal, the transient overvoltage performance of each voltage data point is obtained, including: According to the voltage extreme difference of the voltage data segment where each voltage data point is located and the voltage change degree of each voltage data point, the transient overvoltage dynamic change characteristics of each voltage data point are obtained; the transient overvoltage dynamic change characteristics are proportional to the voltage extreme difference and the voltage change degree; Obtain the difference between the transient overvoltage dynamic change characteristics of the same voltage data point at both ends of the terminal; According to the difference between the transient overvoltage dynamic change characteristics, a transient overvoltage performance degree is obtained; the transient overvoltage performance degree is inversely proportional to the difference between the transient overvoltage dynamic change characteristics; The calculation formula for transient overvoltage performance is given as follows: ； in, Indicates the first voltage data segment Transient overvoltage performance of each voltage data point; Indicates one end of the wiring terminal, that is, the first voltage data in the i-th voltage data segment The transient overvoltage dynamic change characteristics of each voltage data point; Indicates the other end of the wiring terminal, that is, the first voltage data segment in the second voltage data The transient overvoltage dynamic change characteristics of each voltage data point; The voltage anomaly is corrected according to the transient overvoltage manifestation to obtain a target voltage anomaly, including: Obtaining a correction coefficient for each voltage data point according to the transient overvoltage performance degree of each voltage data point, wherein the correction coefficient is inversely proportional to the transient overvoltage performance degree; Multiplying the correction coefficient of each voltage data point by the voltage anomaly of each voltage data point, and the obtained product is the target voltage anomaly of each voltage data point; The calculation formula of target voltage abnormality is given as follows: ； in, Indicates the first voltage data segment Target voltage anomaly for each voltage data point; is the first voltage data segment in the i-th voltage data segment. Correction factor for each voltage data point; According to the target voltage anomaly of each voltage data point, fault detection is performed on the wiring terminal, including: comparing the target voltage abnormality of each voltage data point with a preset voltage abnormality threshold; If there are a preset number of target voltage abnormalities that are greater than or equal to a preset voltage abnormality threshold, it is determined that there is a fault in the connection terminal.

2. A method for detecting voltage at a connection terminal as claimed in claim 1, characterized in that: According to the voltage data, the voltage stability of each voltage data point is obtained, including: Segmenting the voltage data at both ends of the wiring terminal according to the same segmentation rule to obtain a plurality of voltage data segments corresponding to each end of the wiring terminal; Obtaining a difference distance between the voltage data segment and a reference voltage data segment, and obtaining a difference in voltage change degree between each voltage data point in the voltage data segment and a voltage data point at a corresponding position in the reference voltage data segment; According to the difference between the difference distance and the voltage change degree, a trend deviation of the voltage data point is obtained; the trend deviation is proportional to the difference between the difference distance and the voltage change degree; The voltage stability of the voltage data points is obtained according to the trend deviation of the voltage data points corresponding to the two ends of the wiring terminals; the voltage stability is inversely proportional to the trend deviation of the voltage data points corresponding to the two ends of the wiring terminals.

3. A method for detecting voltage at a connection terminal as claimed in claim 2, characterized in that: According to the voltage drop of the same voltage data point at both ends of the wiring terminal in the voltage data, and the current corresponding to the same voltage data point in the current data, the voltage and current variation law characteristics are obtained, including: Obtaining a ratio of a voltage drop corresponding to each voltage data point to a current value corresponding to the voltage data point as a voltage-current variation relationship of the corresponding voltage data point; the voltage drop is a difference in voltage values ​​of the same voltage data point at both ends of the wiring terminal; According to the voltage-current variation relationship between any two adjacent voltage data points, the voltage-current variation regularity characteristics are obtained.

4. A method for detecting voltage at a connection terminal as claimed in claim 3, characterized in that: According to the voltage-current change relationship between any two adjacent voltage data points, the voltage-current change law characteristics are obtained, including: Calculate the difference in the voltage-current variation relationship between any two adjacent voltage data points; The difference between the voltage-current variation relationship of any two adjacent voltage data points is integrated to obtain the overall difference between the voltage-current variation relationship; According to the overall difference of the voltage-current variation relationship, a voltage-current variation law characteristic is obtained, and the voltage-current variation law characteristic is inversely proportional to the overall difference of the voltage-current variation relationship.

5. A terminal voltage detection device, characterized in that: The terminal voltage detection device comprises a unit for executing the terminal voltage detection method according to any one of claims 1 to 4.

6. A terminal voltage detection system, comprising: Memory and processor; The memory is connected to the processor; The memory is used to store program instructions; The processor is used to implement the terminal voltage detection method according to any one of claims 1 to 4 when the program instructions are executed.

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