A method and a detection system for detecting the leakage risk of an electric vehicle charging pile

Abstract

The present invention relates to the field of charging pile monitoring technology, and specifically to a leakage risk detection method and detection system for automobile charging piles, the method comprising: obtaining current data of the charging pile at a target time and within a preset neighborhood; determining the current imbalance of the charging pile at each time using the current data; determining the target leakage risk of the target charging pile and the reference leakage risk of the reference charging pile in the same charging network as the target charging pile using the current imbalance; determining the multi-pile cascade leakage risk of the target charging pile at the target time using the target leakage risk and the reference leakage risk; outputting corresponding early warning information or protection mechanism using the multi-pile cascade leakage risk. The present invention amplifies weak leakage signals through the linkage current characteristics of multiple charging piles, improves the accuracy of leakage risk assessment, and ensures that abnormal fluctuations of the current signal can be accurately captured at the early stage of leakage, thereby triggering safety protection and alarm mechanisms in a timely manner.

Description

Technical Field

[0001] The present invention relates to the technical field of charging pile monitoring, and particularly relates to a leakage risk detection method and detection system for an electric vehicle charging pile. Background Art

[0002] As an important infrastructure for electric vehicle charging, the construction speed and application scope of charging piles are constantly expanding. In the application of high-power AC-DC conversion and high-frequency switching technology, charging piles are prone to leakage due to insulation aging, poor contact or installation defects. This not only causes safety accidents such as electric shock and fire, but may also lead to equipment damage and grid cascading failures, seriously affecting charging safety and system stability. Currently, generally, by monitoring the phase current signals in the charging pile circuit, analyzing and processing them, and judging whether there is a leakage risk according to a preset threshold. When a leakage risk is detected, an alarm signal is triggered, and the power supply of the charging pile can be cut off to prevent the further expansion of the leakage accident.

[0003] However, the initial leakage signals of charging piles are usually very weak and are easily submerged by electromagnetic interference, etc., resulting in possible missed detection of weak abnormal signals in the initial stage, thus increasing safety risks. Summary of the Invention

[0004] In order to solve the technical problem that the initial leakage signals of charging piles are relatively weak and are prone to missed detection due to abnormal signals, leading to safety risks, the purpose of the present invention is to provide a leakage risk detection method and detection system for an electric vehicle charging pile. The specific technical solutions adopted are as follows:

[0005] The present invention provides a leakage risk detection method for an electric vehicle charging pile, and the method includes:

[0006] Obtain the current data of the charging pile at the target moment and within its preset neighborhood range;

[0007] Use the current data to determine the current imbalance of the charging pile at each moment;

[0008] Use the current imbalance to determine the target leakage risk degree of the target charging pile and the reference leakage risk degree of the reference charging pile in the same charging network as the target charging pile;

[0009] Use the target leakage risk degree and the reference leakage risk degree to determine the multi-pile cascading leakage risk degree of the target charging pile at the target moment;

[0010] Use the multi-pile cascading leakage risk degree to output the corresponding warning information or protection mechanism.

[0011] Further, the obtaining the current data of the charging pile at the target moment and within its preset neighborhood range includes:

[0012] Obtain the input current and output current of the charging pile at the target moment and within its preset neighborhood range;

[0013] Among them, the input current represents the current entering the charging pile from the power grid or power source, and the output current represents the current transmitted from the charging pile to the electric vehicle.

[0014] Further, the determining of the current imbalance of the charging pile at each moment by using the current data includes:

[0015] Take the absolute current difference between the input current and the output current of the charging pile at each moment as the current imbalance.

[0016] Further, the determining of the target leakage risk degree of the target charging pile by using the current imbalance includes:

[0017] Use the current imbalance to determine the cumulative trend of the current imbalance of the charging pile at the target moment;

[0018] Use the cumulative trend of the current imbalance and the fluctuation degree of the high-frequency current component within the preset neighborhood range to determine the target leakage risk degree of the target charging pile.

[0019] Further, the determining of the cumulative trend of the current imbalance of the charging pile at the target moment by using the current imbalance includes:

[0020] Use the neighborhood current imbalances at each moment within its preset neighborhood range at the target moment to determine the average value of the change trend of the current imbalance within the preset neighborhood range;

[0021] Use the average value of the change trend of the current imbalance and the target current imbalance at the target moment to calculate the cumulative trend of the current imbalance of the charging pile at the target moment.

[0022] Further, the determining of the multi-pile cascade leakage risk degree of the target charging pile at the target moment by using the target leakage risk degree and the reference leakage risk degree includes:

[0023] Use the reference leakage risk degree to determine the leakage cascade transitivity of the reference charging pile at the target moment;

[0024] Use the leakage cascade transitivity to determine the leakage linkage characteristics of the target charging pile at the target moment;

[0025] Use the target leakage risk degree and the leakage linkage characteristics to calculate the multi-pile cascade leakage risk degree of the target charging pile at the target moment.

[0026] Further, the determining of the leakage cascade transitivity of the reference charging pile at the target moment by using the reference leakage risk degree includes:

[0027] Determine the average value of the leakage risk degree within the preset neighborhood range of the reference charging pile at the target moment;

[0028] Using the reference leakage risk degree and the average value of the leakage risk degree, calculate the reference current transient characteristic of the reference charging pile at the target moment;

[0029] Using the reference current transient characteristic of the reference charging pile at the target moment, determine the leakage cascade transitivity of the reference charging pile at the target moment.

[0030] Further, the determining the leakage cascade transitivity of the reference charging pile at the target moment by using the reference current transient characteristic of the reference charging pile at the target moment includes:

[0031] Determine each intermediate charging pile between the target charging pile and the reference charging pile and each distal charging pile of the reference charging pile far from the target charging pile;

[0032] Determine the intermediate current transient characteristic and the distal current transient characteristic of the intermediate charging pile and the distal charging pile at the target moment respectively;

[0033] Using the reference current transient characteristic, the intermediate current transient characteristic and the distal current transient characteristic, calculate the leakage cascade transitivity of the reference charging pile at the target moment.

[0034] Further, the determining the leakage linkage characteristic of the target charging pile at the target moment by using the leakage cascade transitivity includes:

[0035] Using the leakage cascade transitivity and the reference current transient characteristic, calculate the current common-mode interference amount of the reference charging pile at the target moment;

[0036] Using the current common-mode interference amount and the distance between the target charging pile and the reference charging pile, calculate the leakage linkage characteristic of the target charging pile at the target moment.

[0037] The present invention also provides a leakage risk detection system for an electric vehicle charging pile, and the system is used to implement the leakage risk detection method for an electric vehicle charging pile as described in any one of the above; the system includes:

[0038] A current detection module, configured to obtain current data of the charging pile at the target moment and within its preset neighborhood range;

[0039] A risk assessment module, configured to determine the current imbalance amount of the charging pile at each moment by using the current data; determine the target leakage risk degree of the target charging pile and the reference leakage risk degree of the reference charging pile in the same charging network as the target charging pile by using the current imbalance amount; determine the multi-pile cascade leakage risk degree of the target charging pile at the target moment by using the target leakage risk degree and the reference leakage risk degree;

[0040] The leakage protection module is used to utilize the multi-pile cascade leakage risk to output corresponding warning information or protection mechanism.

[0041] The present invention has the following beneficial effects:

[0042] In the process of judging the leakage risk by monitoring the current signal of the charging pile, since the leakage is weak in the early stage, the general sampling frequency may not be able to capture the current anomaly, and the leakage risk of the charging pile may quickly evolve into a serious safety hazard. Therefore, the present invention judges the possibility of leakage risk by analyzing the initial leakage state of the automobile charging pile and the cascade current performance of the adjacent charging piles. When the detection system recognizes that the charging pile may have weak leakage, the linkage current characteristics of multiple charging piles are used to analyze the linkage current data of multiple charging piles, amplify the weak leakage signal, and improve the accuracy of leakage risk assessment through multi-pile collaborative analysis, accurately capture the initial abnormal signal, and ensure that the abnormal fluctuation of the current signal can be accurately captured at the early stage of leakage, thereby timely triggering the safety protection and alarm mechanism to prevent the leakage risk from rapidly evolving into a serious safety hazard. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] In order to more clearly illustrate the technical solutions and advantages in the embodiments of the present invention or the prior art, the drawings required for use in the embodiments or the prior art descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0044] Figure 1 A flowchart of a method for detecting leakage risk of a vehicle charging pile provided by an embodiment of the present invention;

[0045] Figure 2 A detailed flow chart of step S3 in a method for detecting leakage risk of a vehicle charging pile provided by an embodiment of the present invention;

[0046] Figure 3 A detailed flow chart of step S4 in a method for detecting leakage risk of a vehicle charging pile provided by an embodiment of the present invention;

[0047] Figure 4 A detailed flow chart of step S41 in a method for detecting leakage risk of a vehicle charging pile provided by one embodiment of the present invention;

[0048] Figure 5 It is a structural schematic diagram of the hardware operating environment of the leakage risk detection device of the automobile charging pile involved in the embodiment of the present invention;

[0049] Figure 6Schematic diagram of the framework structure of the leakage risk detection system for an electric vehicle charging pile according to the embodiment of the present invention;

[0050] Figure 7 Schematic diagram of the cascaded operation of multiple charging piles in the same charging network according to the embodiment of the present invention;

[0051] Figure 8 Schematic diagram of the change of the reference leakage risk degree of the reference charging pile according to the embodiment of the present invention. Detailed implementation manners

[0052] In order to further elaborate on the technical means and effects adopted by the present invention to achieve the intended invention purpose, the following describes in detail a method for detecting the leakage risk of an electric vehicle charging pile proposed according to the present invention, its specific implementation manners, structures, features and effects, in conjunction with the accompanying drawings and preferred embodiments. 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.

[0053] 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.

[0054] The following specifically describes the specific solution of a method for detecting the leakage risk of an electric vehicle charging pile provided by the present invention with reference to the accompanying drawings.

[0055] Embodiment 1:

[0056] For the method for detecting the leakage risk of an electric vehicle charging pile provided by the present invention, please refer to Figure 1 , which shows the flowchart of the steps of the method for detecting the leakage risk of an electric vehicle charging pile provided by an embodiment of the present invention.

[0057] The method includes:

[0058] Step S1, obtaining the current data of the charging pile at the target moment and within its preset neighborhood range;

[0059] Specifically, step S1 includes:

[0060] Obtaining the input current and output current of the charging pile at the target moment and within its preset neighborhood range;

[0061] Among them, the input current represents the current entering the charging pile from the power grid or power source, and the output current represents the current transmitted from the charging pile to the electric vehicle.

[0062] In this embodiment, the charging pile refers to an electric vehicle charging pile. Please refer to Figure 7 , Figure 7This is a schematic diagram of cascaded operation of multiple charging piles within the same charging network involved in the embodiment solution of the present invention. As shown in the figure, the power supply end of a general vehicle charging pile is connected to the power grid (or energy storage device), and the discharging end is connected to an electric vehicle to charge the electric vehicle. At the same time, there are generally multiple charging piles within the same charging network, and they usually share the same grounding or neutral line.

[0063] The current data of the charging pile at each moment can be collected through a current sensor and preprocessed. Among them, the target moment can be any moment, and its preset neighborhood range refers to a period of time before the target moment, which can be determined and adjusted according to actual needs. For example, the current data within the preset neighborhood range can include 7 data points, that is, 7 input currents and corresponding 7 output currents.

[0064] For the collection and preprocessing of current data, the following implementation methods can be specifically adopted:

[0065] Use a high-precision current sensor (Hall sensor) to collect the input current and output current. At the positive and negative poles of the DC bus of the vehicle charging pile, a clip-on Hall sensor is adopted, and the analog output of each Hall sensor is connected to a multi-channel high-resolution ADC (Analog-to-Digital Converter) module through a signal conditioning circuit to ensure that each channel can collect data synchronously.

[0066] A digital low-pass filter can be further used to remove high-frequency noise. At the same time, Kalman filtering is used to further smooth the data and extract the real current signal. Zero calibration is performed on the collected data to eliminate the zero drift and bias of the current sensor, ensuring that the output is close to zero when there is no load. By synchronously sampling the data of each channel and adopting moving average processing, the data continuity and stability are ensured, which is convenient for subsequent current balance analysis and leakage risk judgment.

[0067] Step S2, determine the current imbalance of the charging pile at each moment by using the current data;

[0068] Specifically, the step S2 includes:

[0069] Take the absolute current difference between the input current and the output current of the charging pile at each moment as the current imbalance.

[0070] The leakage risk of car charging piles will bring huge safety hazards, and real-time leakage detection is required. During the normal operation of DC car charging piles, the input current and output current should basically remain balanced during the conversion process. If insulation aging, poor contact or internal circuit failure occurs, part of the current may leak through abnormal paths (such as flowing to the device housing or ground wire), causing the output current to be lower than the input current. When the leakage current exceeds the preset safety threshold, the system will determine that there is a leakage risk. However, in the early stage of leakage, the difference between the input and output currents is weak and may not be captured for early warning. Once the leakage risk is not detected in time, it may expand rapidly and generate a larger leakage current, thereby causing serious safety hazards such as electric shock and fire, bringing unpredictable risks to equipment and personnel. Therefore, it is necessary to analyze the current data of the charging pile in real time and capture the suspected leakage state for subsequent analysis.

[0071] According to the charging pile current data, obtain the suspected leakage status:

[0072] When a car charging pile has a leakage risk, part of the current leaks to the ground or the device casing through an unexpected path, resulting in a small but continuous difference between the input and output currents. This current imbalance phenomenon is a direct manifestation of the leakage risk. If the leakage risk is not detected and the power supply is not cut off in time, it may cause electric shock accidents or even electrical fires. Detecting and accurately quantifying tiny current differences in advance can provide early warning at the early stage of the fault.

[0073] When the charging pile is working normally, the input current (i.e. the current entering the charging pile from the power grid or power supply) and the output current (the current transmitted from the charging pile to the electric vehicle through the charging interface) should be equal to form a closed energy transmission loop. However, the risk of leakage will cause the current to pass through an unexpected path, resulting in a difference between the input current and the output current, which is manifested as a current imbalance state. According to the input current and output current of the charging pile, the current imbalance is obtained:

[0074]

[0075] Indicates The first charging pile (as the target charging pile) The current unbalance at a certain moment (target moment); Indicates The first charging station Output current value at each moment; Indicates The first charging station Input current value at a given moment. Indicates The first charging station The absolute difference between the input current and the output current at a certain moment represents the current imbalance.

[0076] Step S3: Determine the target leakage risk degree of the target charging pile and the reference leakage risk degree of the reference charging pile in the same charging network as the target charging pile by using the current imbalance amount;

[0077] Specifically, please refer to Figure 2 , and the step S3 includes:

[0078] Step S31: Determine the cumulative trend of the current imbalance amount of the charging pile at the target moment by using the current imbalance amount;

[0079] More specifically, the step S31 includes:

[0080] Determine the average value of the change trend of the current imbalance amount within the preset neighborhood range by using the neighborhood current imbalance amounts at each moment within the preset neighborhood range of the target moment;

[0081] Calculate the cumulative trend of the current imbalance amount of the charging pile at the target moment by using the average value of the change trend of the current imbalance amount and the target current imbalance amount at the target moment.

[0082] During the operation of the charging pile, tiny leakage signals will accumulate to form a gradually increasing energy loss, which exists in the form of low-amplitude and continuous accumulation. The cumulative effect of the differential current generated by the leakage of the charging pile usually shows a continuously rising trend. Obtain the cumulative trend of the current imbalance amount of the charging pile according to the current imbalance amount obtained from short-term continuous monitoring:

[0083]

[0084] represents the cumulative trend of the current imbalance amount at the -th moment of the -th charging pile; represents the slope of the current imbalance amount at the -th moment of the -th charging pile, representing the current change trend of the current imbalance amount; represents the number of neighborhood current data points (the preset neighborhood range can include the first 7 current data points of the target moment, which can be adjusted specifically); represents the -th moment of the -th charging pile, and the -th moment of the current imbalance amount within the current neighborhood; represents the -th moment of the -th charging pile, and the -th moment of the current imbalance amount within the current neighborhood. represents the -th charging pile, and the The mean value of the change trend of the current imbalance within the current neighborhood at a certain moment represents the overall change of the current imbalance. The larger this formula is, the more the leakage current accumulates and the greater the accumulation trend of the current imbalance; Indicates the th consistency of the change trend of the current imbalance between the is the exponential function with the natural constant as the base.

[0085] In step S32, the target leakage risk degree of the target charging pile is determined by using the accumulation trend of the current imbalance and the fluctuation degree of the high-frequency component of the current within the preset neighborhood range.

[0086] By continuously monitoring and analyzing the small imbalance phenomena in the charging pile current data, the leakage current accumulation trend can be detected in time; at the same time, the leakage current often contains high-frequency components (such as ground leakage noise or harmonic interference). By extracting the high-frequency components in the current data, the characteristics of the leakage current signal can be identified.

[0087] The Fourier transform (FFT) is used to calculate the frequency spectrum distribution of the current signal, and the signal amplitude in the high-frequency range (above 10 kHz) is obtained as the high-frequency component. According to the accumulation trend of the charging pile current imbalance and the high-frequency component in the current data, the leakage risk degree of the charging pile is initially obtained:

[0088]

[0089] Indicates the th target leakage risk degree at the Indicates the th accumulation trend of the current imbalance at the Indicates the th fluctuation degree (current high-frequency component fluctuation degree) of the high-frequency component of the current within the preset neighborhood range at the

[0090] In step S4, the multi-pile cascade leakage risk degree of the target charging pile at the target moment is determined by using the target leakage risk degree and the reference leakage risk degree;

[0091] Specifically, please refer to Figure 3 In step S4, it includes:

[0092] In step S41, the leakage cascade transitivity of the reference charging pile at the target moment is determined by using the reference leakage risk degree;

[0093] More specifically, please refer to Figure 4 , and the step S41 includes:

[0094] Step S410, determining the mean value of the leakage risk degree within the preset neighborhood range of the reference charging pile at the target moment;

[0095] Step S411, calculating the reference current transient characteristics of the reference charging pile at the target moment by using the reference leakage risk degree and the mean value of the leakage risk degree;

[0096] When the initial leakage signal of a charging pile is very weak, it is often difficult to trigger the protection mechanism by analyzing its current data alone because its leakage current may be much lower than the set safety threshold. However, in a charging network, multiple charging piles usually share the same grounding or neutral line. When a charging pile has a weak leakage, its leakage current will affect adjacent charging piles through the grid coupling effect, and the linkage effect will form a global current anomaly in the overall charging network. By comprehensively analyzing the linkage current data of the vehicle charging piles in the same charging network, the small anomalies of a single device can be quantified and amplified, so as to more accurately judge whether there is a leakage risk in the whole area.

[0097] Analyzing the current data of multiple charging piles in linkage to evaluate the leakage risk:

[0098] In the same charging network, multiple charging piles share a common power supply line and a grounding system. Therefore, when a certain charging pile has a leakage, its leakage current may be coupled to other charging piles through the grounding wire or the power supply line, resulting in transient changes in the current signals of adjacent charging piles, manifested as a sudden increase in the leakage risk degree, which is actually caused by the influence of the leaking charging pile.

[0099] Please refer to Figure 8 , Figure 8 It is a schematic diagram of the change of the reference leakage risk degree of the reference charging pile involved in the solution of the embodiment of the present invention. Among them, the horizontal axis is time, with the unit of second, and the vertical axis is the normalized value of the leakage risk degree. As shown in the figure, it reflects the change of the leakage risk degree of a certain charging pile (reference charging pile) outside the target charging pile under the same charging network. During normal operation, when a certain charging pile leaks, it interferes with the reference charging pile through the same charging network, resulting in current imbalance and an increase in the leakage risk degree at the same time.

[0100] Obtaining the current transient characteristics of other charging piles (reference charging piles) in the same charging network according to the leakage risk degree of the charging pile at the same moment:

[0101]

[0102] Denote the The current transient characteristics of the th charging pile (reference charging pile) in the same charging network at the th moment; Indicates the th charging pile's reference leakage risk degree at the th moment in the same charging network; Indicates the average leakage risk degree of the th charging pile within its preset neighborhood range (here the preset neighborhood range can be 10 data points before the target moment, which can be adjusted specifically) at the th moment in the same charging network; th charging pile; Indicates the difference in leakage risk between the th charging pile at the th moment in the same charging network and the leakage risk within the neighborhood range, representing the associated influence on the th charging pile in the same charging network caused by the th charging pile. When this formula value is larger, it indicates that when the th charging pile has a leakage risk, the th charging pile is affected by the ground wire network leakage and has a greater instantaneous change in current imbalance. th charging pile; th charging pile.

[0103] Step S412: Use the reference current transient characteristics of the reference charging pile at the target moment to determine the leakage cascade transitivity of the reference charging pile at the target moment.

[0104] For the step S412, it specifically includes:

[0105] Determine each intermediate charging pile between the target charging pile and the reference charging pile, and each distal charging pile of the reference charging pile far from the target charging pile;

[0106] Determine the intermediate current transient characteristics and distal current transient characteristics of the intermediate charging pile and the distal charging pile at the target moment respectively;

[0107] Use the reference current transient characteristics, intermediate current transient characteristics, and distal current transient characteristics to calculate the leakage cascade transitivity of the reference charging pile at the target moment.

[0108] Continue to refer to Figure 7, since each charging pile usually shares the same ground or neutral wire, when a faulty charging pile with leakage occurs, its leakage current will be transmitted along the common connection to neighboring charging piles. The physical distance between different charging piles determines the attenuation degree of the leakage signal at each node: charging piles closer to the faulty one are more significantly affected, showing higher transient current amplitudes and longer durations, while charging piles farther away will show weaker transient current signals. By comparing the current transient characteristics of different charging piles according to their distances from the faulty charging pile, the cascading transmission effect of the leakage signal can be quantified.

[0109] As Figure 7 shown, when the o-th charging pile has a leakage risk, according to the direction of the arrow, the degree of influence on other charging piles gradually decreases, showing the transmissibility of the leakage effect.

[0110] According to the distances of other charging piles from the faulty charging pile in the same charging network, by comparing the current transient characteristics, the cascading transmissibility of leakage for other charging piles can be obtained:

[0111]

[0112] represents the cascading transmissibility of leakage at the -th moment of the -th charging pile in the same charging network as the -th charging pile; represents the number of charging piles between the -th charging pile position and the -th charging pile in the same charging network (here referring to the intermediate charging piles, which can be arranged in order according to the distance); represents the current transient characteristic at the -th moment of the -th intermediate charging pile in the same charging network as the -th charging pile; represents the reference current transient characteristic at the -th moment of the -th charging pile in the same charging network as the -th charging pile; represents the number of charging piles far from the -th charging pile in the same charging network as the -th charging pile (here referring to the remote charging piles); represents the current transient characteristic at the -th moment of the -th remote charging pile in the same charging network as the -th charging pile. represents the charging piles between the -th charging pile position and the -th charging pile in the same charging network and the The difference in the current transient characteristics of a charging pile represents the transmissibility of the leakage effect. The closer a charging pile is to the leaking charging pile, the greater the impact it receives, and thus the greater the current transient characteristics. It represents the th charging pile in the same charging network that is far from the th charging pile and the difference in the current transient characteristics between the th charging pile and the is a linear normalization function.

[0113] Step S42: Using the leakage cascade transmissibility, determine the leakage linkage characteristics of the target charging pile at the target moment;

[0114] Specifically, step S42 includes:

[0115] Using the leakage cascade transmissibility and the reference current transient characteristics, calculate the current common-mode interference amount of the reference charging pile at the target moment;

[0116] Using the current common-mode interference amount and the distance between the target charging pile and the reference charging pile, calculate the leakage linkage characteristics of the target charging pile at the target moment.

[0117] When a single charging pile leaks, its weak abnormal signal may be difficult to independently trigger the protection mechanism. However, due to the electrical coupling between charging piles in the network, the leakage signal will accumulate in the common grounding system, thus forming current transient characteristics on other charging piles. By monitoring and comparing the current data of multiple charging piles, it is possible to determine whether the current imbalance is global, showing a consistent upward trend or a mutation phenomenon, thereby providing a more accurate early warning basis for the leakage risk.

[0118] Since multiple charging piles share a common ground or neutral line, when a leakage risk occurs in one charging pile, its leakage signal will be transmitted to other charging piles through the grid coupling effect. When other reference charging piles simultaneously exhibit current transient characteristics and leakage cascade transmissibility, the reference charging pile is affected by the common-mode interference of the leaking charging pile. According to the current transient characteristics and leakage cascade transmissibility of the reference charging piles belonging to the same charging network, obtain the current common-mode interference of the reference charging piles affected by the leaking charging pile:

[0119]

[0120] represents the th charging pile and the current common-mode interference amount received by the th charging pile in the same charging network at the th moment; represents the th charging pile and the current common-mode interference amount received by the th charging pile in the same charging network at the Reference current transient characteristics at a certain moment; Indicating the th charging pile's leakage cascade transitivity at the th moment within the same charging network. Leakage cascade transitivity at the

[0121] The leakage of a single charging pile not only manifests as a weak current imbalance in its own circuit, but may also transmit interference to adjacent devices through a common ground or neutral line. Depending on the distance, the degree of common-mode interference received is different. When there is a leakage risk, all surrounding charging piles are affected by the common-mode interference, and even there is a trend change in the degree of interference according to the distance. Then, it can be preliminarily determined that there is a leakage linkage phenomenon. According to the degree of current common-mode interference of multiple charging piles by the leaking charging pile, the leakage linkage characteristics of the charging pile are obtained:

[0122]

[0123] Indicating the th charging pile's leakage linkage characteristics at the Indicating the number of charging piles within the same charging network; Indicating the th charging pile's distance from the th charging pile within the same charging network; Indicating the th charging pile's th moment's received current common-mode interference amount within the same charging network. Indicating the th charging pile's distance from the th charging pile within the same charging network as the weight of the leakage cascade effect. The smaller the distance, the greater the influence of the leakage cascade effect; Indicating that according to the distance between the th charging pile and the th charging pile, the current common-mode interference received by the reference charging pile within the same charging network is weighted and averaged. The closer the distance, the greater the interference, and the greater the leakage linkage characteristics; is the sigmoid function; it should be noted that to ensure the meaningfulness of the calculation results, in the embodiments of the present invention, when performing fractional operations and encountering the case where the denominator is 0, a tuning parameter factor greater than 0 needs to be added to the denominator to prevent the denominator from being 0. The value of the tuning parameter factor is set by the implementer according to the actual situation, and this application does not make special restrictions. is the sigmoid function; it should be noted that to ensure the meaningfulness of the calculation results, in the embodiments of the present invention, when performing fractional operations and encountering the case where the denominator is 0, a tuning parameter factor greater than 0 needs to be added to the denominator to prevent the denominator from being 0. The value of the tuning parameter factor is set by the implementer according to the actual situation, and this application does not make special restrictions.

[0124] Step S43: Calculate the multi-pile cascade leakage risk degree of the target charging pile at the target moment by using the target leakage risk degree and the leakage linkage feature.

[0125] When a charging pile has a leakage risk, since other charging piles are in the same charging network, their current data will inevitably be affected. When multiple charging piles show a leakage cascade response, the weak initial leakage signal of a single charging pile can be amplified to obtain a more accurate leakage risk assessment. According to the leakage linkage feature and the leakage risk degree of the charging pile, the multi-pile cascade leakage risk of the charging pile is obtained:

[0126]

[0127] Denote the multi-pile cascade leakage risk degree of the th charging pile at the th moment; Denote the leakage linkage feature of the th charging pile at the th moment; Denote the target leakage risk degree of the th charging pile at the th moment.

[0128] Step S5: Output the corresponding warning information or protection mechanism by using the multi-pile cascade leakage risk degree.

[0129] After obtaining the multi-pile cascade leakage risk degree of the charging pile, the system can take corresponding warning and protection measures according to the risk level. When the multi-pile cascade leakage risk of the charging pile is within the first risk range (such as 0 - 0.3), the system can prompt the maintenance personnel to pay attention and regularly check the grounding situation; when the leakage risk is within the second risk range (such as 0.3 - 0.6), the system can issue a yellow warning and notify the maintenance personnel to detect the circuit condition of the charging pile in detail; if the leakage risk reaches the third risk range (such as exceeding 0.6), the system can immediately trigger the open-circuit protection mechanism to cut off the power supply of the charging pile to prevent safety accidents. By dynamically adjusting the sampling frequency to extract the current detail features, the leakage detection is made more accurate and reliable, and timely warning can be achieved in the early stage of the leakage risk, effectively ensuring the safety of the charging pile and the surrounding environment.

[0130] Embodiment 2:

[0131] The embodiment of the present invention also proposes a leakage risk detection device for an electric vehicle charging pile. The leakage risk detection device for the electric vehicle charging pile can be a data calculation and processing device such as a charging pile, a computer, a server, or a combination of multiple devices.

[0132] As Figure 5 shown, Figure 5It is a schematic structural diagram of the hardware operating environment of the leakage risk detection device for an electric vehicle charging pile involved in the embodiment of the present invention.

[0133] As shown in Figure 5 , the leakage risk detection device for the electric vehicle charging pile may include: a processor 1001, such as a CPU, a network interface 1004, a user interface 1003, a memory 1005, and a communication bus 1002. Among them, the communication bus 1002 is used to realize the connection and communication between these components. The user interface 1003 may include a display (Display) and an input unit such as a control panel. Optionally, the user interface 1003 may further include a standard wired interface and a wireless interface. The network interface 1004 may optionally include a standard wired interface and a wireless interface (such as a WIFI interface). The memory 1005 may be a high-speed RAM memory or a stable memory (non-volatile memory), such as a disk memory. Optionally, the memory 1005 may also be a storage device independent of the foregoing processor 1001. The memory 1005, as a computer storage medium, may include a leakage risk detection program.

[0134] Those skilled in the art can understand that Figure 5 the hardware structure shown in

[0135] does not constitute a limitation to the device, and may include more or fewer components than shown in the figure, or combine some components, or have different component arrangements. Figure 5 , Figure 5 the memory 1005, as a computer-readable storage medium, may include an operating system, a user interface module, a network communication module, and a leakage risk detection program.

[0136] In Figure 5 , the network communication module is mainly used to connect to the server and can communicate with the server for data; while the processor 1001 can call the leakage risk detection program stored in the memory 1005 and execute the steps in each of the above embodiments.

[0137] Based on the above hardware structure of the leakage risk detection device for the electric vehicle charging pile, each embodiment for implementing the leakage risk detection method for the electric vehicle charging pile of the present invention is realized.

[0138] In addition, the present invention further provides a leakage risk detection system for an electric vehicle charging pile. Please refer to Figure 6 , the leakage risk detection system for the electric vehicle charging pile includes:

[0139] a current detection module A10, configured to obtain current data of the charging pile at a target moment and within its preset neighborhood range;

[0140] A risk assessment module A20 is used to determine the current imbalance of the charging pile at each moment by using current data; determine the target leakage risk degree of the target charging pile and the reference leakage risk degree of the reference charging pile in the same charging network as the target charging pile by using the current imbalance; and determine the multi-pile cascade leakage risk degree of the target charging pile at the target moment by using the target leakage risk degree and the reference leakage risk degree.

[0141] A leakage protection module A30 is used to output corresponding warning information or protection mechanisms by using the multi-pile cascade leakage risk degree.

[0142] Further, the current detection module A10 is further used for:

[0143] Obtain the input current and output current of the charging pile at the target moment and within its preset neighborhood range;

[0144] Wherein, the input current represents the current entering the charging pile from the power grid or power source, and the output current represents the current transmitted from the charging pile to the electric vehicle.

[0145] Further, the risk assessment module A20 is further used for:

[0146] Take the absolute current difference between the input current and the output current of the charging pile at each moment as the current imbalance.

[0147] Further, the risk assessment module A20 is further used for:

[0148] Determine the cumulative trend of the current imbalance of the charging pile at the target moment by using the current imbalance;

[0149] Determine the target leakage risk degree of the target charging pile by using the cumulative trend of the current imbalance and the fluctuation degree of the high-frequency current component within the preset neighborhood range.

[0150] Further, the risk assessment module A20 is further used for:

[0151] Determine the average change trend of the current imbalance within the preset neighborhood range by using the neighborhood current imbalance at each moment within the preset neighborhood range of the target moment;

[0152] Calculate the cumulative trend of the current imbalance of the charging pile at the target moment by using the average change trend of the current imbalance and the target current imbalance at the target moment.

[0153] Further, the risk assessment module A20 is further used for:

[0154] Determine the leakage cascade transitivity of the reference charging pile at the target moment by using the reference leakage risk degree;

[0155] Determine the leakage linkage characteristics of the target charging pile at the target moment by using the leakage cascade transitivity;

[0156] Calculate the multi-pile cascade leakage risk degree of the target charging pile at the target moment by using the target leakage risk degree and the leakage linkage characteristics.

[0157] Furthermore, the risk assessment module A20 is further configured to:

[0158] Determine the average value of the leakage risk degrees within the preset neighborhood range of the reference charging pile at the target moment;

[0159] Calculate the reference current transient characteristics of the reference charging pile at the target moment by using the reference leakage risk degree and the average value of the leakage risk degrees;

[0160] Determine the leakage cascade transitivity of the reference charging pile at the target moment by using the reference current transient characteristics of the reference charging pile at the target moment.

[0161] Furthermore, the risk assessment module A20 is further configured to:

[0162] Determine each intermediate charging pile between the target charging pile and the reference charging pile and each distal charging pile of the reference charging pile far from the target charging pile;

[0163] Determine the intermediate current transient characteristics and the distal current transient characteristics of the intermediate charging pile and the distal charging pile at the target moment respectively;

[0164] Calculate the leakage cascade transitivity of the reference charging pile at the target moment by using the reference current transient characteristics, the intermediate current transient characteristics and the distal current transient characteristics.

[0165] Furthermore, the risk assessment module A20 is further configured to:

[0166] Calculate the current common-mode interference amount of the reference charging pile at the target moment by using the leakage cascade transitivity and the reference current transient characteristics;

[0167] Calculate the leakage linkage characteristics of the target charging pile at the target moment by using the current common-mode interference amount and the distance between the target charging pile and the reference charging pile.

[0168] The specific implementation manners of the leakage risk detection system of the vehicle charging pile of the present invention are basically the same as those of the embodiments of the above-mentioned leakage risk detection method of the vehicle charging pile, and will not be elaborated herein.

[0169] In addition, the present invention further provides a computer-readable storage medium. A leakage risk detection program is stored on the computer-readable storage medium of the present invention. When the leakage risk detection program is executed by a processor, the steps of the above-mentioned leakage risk detection method of the vehicle charging pile are implemented.

[0170] Among them, the method implemented when the leakage risk detection program is executed can refer to the various embodiments of the leakage risk detection method of the vehicle charging pile of the present invention, which will not be elaborated here.

[0171] It should be noted that: the above-mentioned 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.

[0172] Each embodiment in this specification is described in a progressive manner. For the same or similar parts among the embodiments, reference can be made to each other. Each embodiment focuses on the differences from the reference embodiment.

[0173] Those skilled in the art should understand that the embodiments of the present invention can be provided as a method, a system, or a computer program product. Therefore, the present invention can take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present invention can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0174] The above are only the preferred embodiments of the present invention, and do not limit the protection scope of the present invention accordingly. Any equivalent structure / method transformation made by using the specification and drawings of the present invention under the inventive concept of the present invention, or any direct / indirect application in the relevant technical fields is included in the protection scope of the present invention.

Claims

1. A method for detecting the leakage risk of an electric vehicle charging pile, characterized in that The method includes: Obtaining current data of a charging pile at a target moment and within its preset neighborhood range; Determining the current imbalance of the charging pile at each moment by using the current data; Determining the target leakage risk degree of the target charging pile and the reference leakage risk degree of a reference charging pile within the same charging network as the target charging pile by using the current imbalance; Determining the multi-pile cascade leakage risk degree of the target charging pile at the target moment by using the target leakage risk degree and the reference leakage risk degree; Outputting corresponding warning information or protection mechanism by using the multi-pile cascade leakage risk degree; The determining the multi-pile cascade leakage risk degree of the target charging pile at the target moment by using the target leakage risk degree and the reference leakage risk degree includes: Determining the leakage cascade transitivity of the reference charging pile at the target moment by using the reference leakage risk degree; Determining the leakage linkage characteristics of the target charging pile at the target moment by using the leakage cascade transitivity; Calculating the multi-pile cascade leakage risk degree of the target charging pile at the target moment by using the target leakage risk degree and the leakage linkage characteristics; The determining the leakage cascade transitivity of the reference charging pile at the target moment by using the reference leakage risk degree includes: Determining the mean value of the leakage risk degree within the preset neighborhood range of the reference charging pile at the target moment; Calculating the reference current transient characteristics of the reference charging pile at the target moment by using the reference leakage risk degree and the mean value of the leakage risk degree; Determining the leakage cascade transitivity of the reference charging pile at the target moment by using the reference current transient characteristics of the reference charging pile at the target moment; The determining the leakage cascade transitivity of the reference charging pile at the target moment by using the reference current transient characteristics of the reference charging pile at the target moment includes: Determining each intermediate charging pile between the target charging pile and the reference charging pile and each distal charging pile of the reference charging pile far from the target charging pile; Determining the intermediate current transient characteristics and the distal current transient characteristics of the intermediate charging pile and the distal charging pile at the target moment respectively; Calculating the leakage cascade transitivity of the reference charging pile at the target moment by using the reference current transient characteristics, the intermediate current transient characteristics and the distal current transient characteristics; The determining the leakage linkage characteristics of the target charging pile at the target moment by using the leakage cascade transitivity includes: Calculating the current common-mode interference amount of the reference charging pile at the target moment by using the leakage cascade transitivity and the reference current transient characteristics; Calculating the leakage linkage characteristics of the target charging pile at the target moment by using the current common-mode interference amount and the distance between the target charging pile and the reference charging pile.

2. The method for detecting the leakage risk of an electric vehicle charging pile according to claim 1, wherein, The obtaining current data of a charging pile at a target moment and within its preset neighborhood range includes: Obtaining the input current and the output current of the charging pile at the target moment and within its preset neighborhood range; Wherein, the input current represents the current entering the charging pile from the power grid or power source, and the output current represents the current transmitted from the charging pile to the electric vehicle.

3. The method for detecting the leakage risk of an electric vehicle charger according to claim 2, wherein The determining the current imbalance of the charging pile at each moment by using the current data includes: Taking the absolute current difference between the input current and the output current of the charging pile at each moment as the current imbalance.

4. The method for detecting the leakage risk of an electric vehicle charging pile according to claim 1, characterized in that, The determining the target leakage risk degree of the target charging pile by using the current imbalance includes: Determine the cumulative trend of the current imbalance of the charging pile at the target moment using the current imbalance amount; Determine the target leakage risk degree of the target charging pile using the cumulative trend of the current imbalance amount and the fluctuation degree of the high-frequency current components within the preset neighborhood range.

5. The method for detecting the leakage risk of an electric vehicle charging pile according to claim 4, characterized in that, The determining the cumulative trend of the current imbalance of the charging pile at the target moment using the current imbalance amount includes: Determine the average value of the change trend of the current imbalance amount within the preset neighborhood range using the neighborhood current imbalance amounts at each moment within the preset neighborhood range of the target moment; Calculate the cumulative trend of the current imbalance amount of the charging pile at the target moment using the average value of the change trend of the current imbalance amount and the target current imbalance amount at the target moment.

6. A leakage risk detection system for an electric vehicle charging pile, characterized in that, The system is used to implement the leakage risk detection method of the vehicle charging pile according to any one of claims 1 to 5; the system includes: A current detection module, configured to obtain the current data of the charging pile at the target moment and within its preset neighborhood range; A risk assessment module, configured to determine the current imbalance amount of the charging pile at each moment using the current data; determine the target leakage risk degree of the target charging pile and the reference leakage risk degree of the reference charging pile in the same charging network as the target charging pile using the current imbalance amount; determine the multi-pile cascade leakage risk degree of the target charging pile at the target moment using the target leakage risk degree and the reference leakage risk degree; A leakage protection module, configured to output corresponding warning information or protection mechanisms using the multi-pile cascade leakage risk degree.

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