Method for testing electrical performance of copper bar energy storage connector

Abstract

The invention relates to the technical field of electrical variable measurement, in particular to a copper bar energy storage connector electrical performance test method, which comprises the following steps: acquiring temperature data of a copper bar energy storage connector under different currents; determining temperature abnormal parameters of the copper bar energy storage connector under the current; determining initial abnormal parameters of the copper bar energy storage connector; determining a first abnormal characteristic of the copper bar energy storage connector before the temperature abnormity occurs for the first time; starting from the current when the abnormality occurs for the first time, arranging the following currents according to the magnitude sequence to obtain a current sequence, and taking the temperature data of each current in the current sequence at the last moment as the temperature data of the copper bar energy storage connector under each current to obtain a temperature sequence corresponding to the current sequence; determining the possibility that the abnormal temperature of the copper bar energy storage connector is insufficient in current-carrying capacity; and determining the current-carrying performance of the copper bar energy storage connector. According to the invention, the evaluation accuracy of the current-carrying performance of the copper bar energy storage connector is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of electrical variable measurement, and particularly relates to a method for testing the electrical performance of a copper bus energy storage connector. Background Art

[0002] A copper bus energy storage connector is an electrical connector used to connect energy storage devices such as battery packs, supercapacitors, etc. It uses a copper bus as the main conductive medium to ensure the efficient, stable and safe flow of current between different energy storage units or between energy storage devices and external circuits.

[0003] In some scenarios, the produced copper bus energy storage connectors may have electrical performance problems such as poor conductivity, poor insulation, poor contact, and poor current-carrying performance. The impacts caused by different performance problems are not exactly the same. For example, when the contact resistance increases or the current-carrying capacity is insufficient, the conductivity will be poor, resulting in too high a temperature, affecting the charge and discharge speed, and affecting the overall use efficiency. Among them, for the current-carrying performance of copper bus energy storage connectors, the traditional direct measurement method is to measure the current and temperature parameters to determine the current-carrying performance of copper bus energy storage connectors, and evaluate the electrical performance of copper bus energy storage connectors through the current-carrying performance. However, the test results of current and temperature are affected by the poor contact between the machine and the test equipment, resulting in a low accuracy of evaluating the current-carrying performance of copper bus energy storage connectors. Summary of the Invention

[0004] In order to solve the technical problem of low accuracy in evaluating the current-carrying performance of copper bus energy storage connectors, the purpose of the present invention is to provide a method for testing the electrical performance of copper bus energy storage connectors, and the specific technical solutions adopted are as follows: In a first aspect, an embodiment of the present invention provides a method for testing the electrical performance of a copper bus energy storage connector, including: obtaining temperature data of the copper bus energy storage connector at different currents; determining the temperature anomaly parameter of the copper bus energy storage connector at a current according to the total duration of the temperature change of the copper bus energy storage connector at the current and the temperature data at each moment of the current; determining the initial anomaly parameter of the copper bus energy storage connector according to the temperature anomaly parameter and the temperature data of the current copper bus energy storage connector and other copper bus energy storage connectors at the last moment; determining the first anomaly feature before the first temperature anomaly of the copper bus energy storage connector according to the initial anomaly parameter; starting from the current when the first anomaly occurs, arranging the currents sorted after it in ascending order to obtain a current sequence, and taking the temperature data at the last moment of each current in the current sequence as the temperature data of the copper bus energy storage connector at each current to obtain a temperature sequence corresponding to the current sequence; determining the possibility that the temperature anomaly of the copper bus energy storage connector is caused by insufficient current-carrying capacity according to the first anomaly feature, the temperature sequence and the current sequence; and determining the current-carrying performance of the copper bus energy storage connector according to the possibility.

[0005] Optionally, determining the current-carrying performance of the copper busbar energy storage connector according to the possibility includes: when the possibility is greater than the first threshold, determining that the current-carrying performance of the copper busbar energy storage connector is insufficient; when the possibility is less than or equal to the first threshold, determining that the current-carrying performance of the copper busbar energy storage connector is normal; determining the copper busbar energy storage connector with normal current-carrying performance as the target copper busbar energy storage connector, starting from the current magnitude at the first temperature anomaly of the target copper busbar energy storage connector, increasing the current by a predetermined value of the rated current each time, and measuring the first average value of the temperature data at the last moment during the temperature change time after each current increase; calculating the first difference between the first average value of each target copper busbar energy storage connector and the temperature limit, marking the first difference greater than or equal to the second threshold as the first value, and marking the first difference less than the second threshold as the second value; arranging and numbering the first values and the second values in chronological order to obtain a numerical sequence; determining the current-carrying performance parameters of the target copper busbar energy storage connector according to the target current data at the first temperature anomaly of the target copper busbar energy storage connector, the number of the first first value in the numerical sequence, the number of the first values, and the possibility of the target copper busbar energy storage connector; determining the current-carrying performance of the target copper busbar energy storage connector according to the current-carrying performance parameters.

[0006] Optionally, determining the current-carrying performance parameters of the target copper busbar energy storage connector according to the target current data at the first temperature anomaly of the target copper busbar energy storage connector, the number of the first first value in the numerical sequence, the number of the first values, and the possibility of the target copper busbar energy storage connector includes: calculating the first product between the possibility of the target copper busbar energy storage connector and the number of the first values, and performing inverse proportional normalization processing on the first product to obtain a normalized product; calculating the second product between the target current data, the number of the first first value, and the normalized product; performing normalization processing on the second product to obtain the current-carrying performance parameters of the target copper busbar energy storage connector.

[0007] Optionally, determining the temperature anomaly parameters of the copper busbar energy storage connector under the current according to the total duration of the temperature change of the copper busbar energy storage connector under the current and the temperature data at each moment of the current includes: determining the temperature change rate of the copper busbar energy storage connector according to the total duration of the temperature change of the copper busbar energy storage connector under the current, the last temperature data of the copper busbar energy storage connector, and the first temperature data of the copper busbar energy storage connector; taking the maximum value of the temperature change rates of all the copper busbar energy storage connectors; determining the temperature data of the copper busbar energy storage connector at the last N moments under the current, and calculating the second difference between the temperature data at adjacent moments among the N moments, where N is a natural number greater than or equal to 2; calculating the second average value of each second difference and the third average value of the third difference between each second difference; determining the temperature anomaly parameters of the copper busbar energy storage connector under the current according to the temperature change rate, the maximum value, the second average value, and the third average value.

[0008] Optionally, determining the temperature change rate of the copper bar energy storage connector based on the total duration of the temperature change of the copper bar energy storage connector under current, the last temperature data of the copper bar energy storage connector, and the first temperature data of the copper bar energy storage connector includes: calculating a fourth difference between the last temperature data and the first temperature data; determining a first ratio between the fourth difference and the total duration as the temperature change rate of the copper bar energy storage connector.

[0009] Optionally, determining the temperature anomaly parameter of the copper bar energy storage connector under current based on the temperature change rate, the maximum value, the second average value, and the third average value includes: calculating a second ratio between the temperature change rate and the maximum value and a third product between the second average value and the third average value; determining a fourth product between the second ratio and the third product as the temperature anomaly parameter of the copper bar energy storage connector under current.

[0010] Optionally, determining the initial anomaly parameter of the copper bar energy storage connector based on the temperature anomaly parameter and the temperature data of the current copper bar energy storage connector and other copper bar energy storage connectors at the last moment includes: calculating a fourth average value of the fifth differences between the temperature data of the current copper bar energy storage connector and other copper bar energy storage connectors at the last moment; calculating a fifth product between the fourth average value and the temperature anomaly parameter, and performing a normalization process on the fifth product to obtain the initial anomaly parameter of the copper bar energy storage connector.

[0011] Optionally, determining the first anomaly feature before the copper bar energy storage connector first exhibits a temperature anomaly based on the initial anomaly parameter includes: when the initial anomaly parameter is greater than or equal to a third threshold, determining that the temperature of the copper bar energy storage connector under current is abnormal; sorting all currents in ascending order and numbering them, and calculating the first variance of the initial anomaly parameters corresponding to all currents before the current at which the temperature of the copper bar energy storage connector first exhibits an anomaly; performing an inverse proportional normalization process on the first variance to obtain a normalized variance; determining a sixth product between the number of the current at which the temperature of the copper bar energy storage connector first exhibits an anomaly and the first variance as the first anomaly feature before the copper bar energy storage connector first exhibits a temperature anomaly.

[0012] Optionally, the possibilities of determining that the temperature anomaly of the copper bus energy storage connector is caused by insufficient current-carrying capacity based on the first anomaly feature, the temperature sequence, and the current sequence include: calculating the second variance of the temperature data in the temperature sequence and calculating the fifth average value of the second variance; plotting the current-temperature change curve of the copper bus energy storage connector according to the temperature sequence and the current sequence, and obtaining the slope of the current-temperature change curve; calculating the seventh product between the slope and the fifth average value, and performing inverse proportional normalization on the seventh product to obtain a normalized value; calculating the eighth product between the normalized value and the first anomaly feature; normalizing the eighth product to obtain the possibility that the temperature anomaly of the copper bus energy storage connector is caused by insufficient current-carrying capacity.

[0013] Optionally, the second threshold is 0.

[0014] The present invention has the following beneficial effects: First, obtain the temperature data of the copper bus energy storage connector under different currents; then determine the temperature anomaly parameter of the copper bus energy storage connector under the current according to the total duration of the temperature change of the copper bus energy storage connector under the current and the temperature data at each moment of the current; and determine the initial anomaly parameter of the copper bus energy storage connector according to the temperature anomaly parameter and the temperature data of the current copper bus energy storage connector and other copper bus energy storage connectors at the last moment; secondly, determine the first anomaly feature before the copper bus energy storage connector first shows a temperature anomaly according to the initial anomaly parameter; then, starting from the current at which the anomaly first appears, arrange the currents sorted after it in descending order to obtain a current sequence, and use the temperature data at the last moment of each current in the current sequence as the temperature data of the copper bus energy storage connector under each current to obtain a temperature sequence corresponding to the current sequence; and determine the possibility that the temperature anomaly of the copper bus energy storage connector is caused by insufficient current-carrying capacity according to the temperature sequence and the current sequence; finally, determine the current-carrying performance of the copper bus energy storage connector according to the possibility.

[0015] Thus, the embodiments of the present invention can analyze the temperature data of the copper bus energy storage connector under different currents, obtain the temperature anomaly parameters of the copper bus energy storage connector under the current, and further determine the initial anomaly parameters of the copper bus energy storage connector according to the current temperature anomaly parameters of the copper bus energy storage connector and the temperature data of other copper bus energy storage connectors. According to the initial anomaly parameters, the first anomaly feature before the copper bus energy storage connector first appears temperature anomaly is determined, and according to the first anomaly feature, temperature sequence and current sequence, the possibility that the temperature anomaly of the copper bus energy storage connector is caused by insufficient current-carrying capacity is further determined, and the current-carrying performance of the copper bus energy storage connector is determined according to this possibility. Thus, the embodiments of the present invention combine the temperature data and current data of different copper bus energy storage connectors to test the current-carrying performance of the copper bus energy storage connector, improving the test accuracy of the current-carrying performance. It avoids the influence of poor contact between the machine and the test equipment on the test results of the current and temperature of a certain copper bus energy storage connector, and improves the evaluation accuracy of the current-carrying performance of the copper bus energy storage connector. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions and advantages in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following described drawings are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained according to these drawings.

[0017] Figure 1 It is a flowchart of a method for testing the electrical performance of a copper bus energy storage connector provided by an embodiment of the present invention.

[0018] Figure 2 It is a schematic diagram of a temperature-time change curve provided by an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0019] In order to further elaborate on the technical means and effects adopted by the present invention to achieve the intended invention purpose, the following, in combination with the accompanying drawings and preferred embodiments, details the specific implementation manners, structures, features and effects of a method for testing the electrical performance of a copper bus energy storage connector proposed according to 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.

[0020] 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.

[0021] The following specifically describes the specific solution of a method for testing the electrical performance of a copper bus energy storage connector provided by the present invention in conjunction with the accompanying drawings.

[0022] Embodiment 1: Please refer to Figure 1 , which shows a flowchart of a method for testing the electrical performance of a copper bus energy storage connector provided by an embodiment of the present invention, including: S101, obtaining temperature data of the copper bus energy storage connector at different currents.

[0023] Specifically, in the embodiment of the present invention, a high-current generator is used as the power supply, and the copper bus energy storage connector is connected to the test circuit. During the connection, it is necessary to ensure a firm connection to avoid interference of the contact resistance on the test results. Appropriate clamps can be used at the connection points, and conductive paste can be applied to reduce the contact resistance. Then, the power supply is energized, and the current is gradually increased. It can start from a relatively small value, such as 10% of the rated current of the power supply, and then increase step by step according to a certain gradient, such as increasing 10% of the rated current each time, and increasing the current every ten minutes until the rated current of the copper bus energy storage connector and a certain value beyond the rated current are reached, for example, 50A beyond the rated current.

[0024] Furthermore, starting from the power-on, continuously record the temperature data of the copper bus energy storage connector at different moments at a fixed time interval under the same current. Then, plot the temperature-time curve of the copper bus energy storage connector. For example, within 10 minutes from the power-on, record the temperature every 30 seconds. A data acquisition system can be used to automatically record the data. Exemplarily, as Figure 2 shown, Figure 2 is a schematic diagram of a temperature-time change curve provided by an embodiment of the present invention. Figure 2 In, the horizontal axis represents time, and the vertical axis represents temperature. According to the thermodynamic principle during the operation of the copper bus energy storage connector, during the current-carrying process, for a copper bus energy storage connector with good current-carrying capacity, when there is current passing through, heat will accumulate rapidly, the temperature will start to rise rapidly, and then the temperature rise rate will gradually slow down, and finally the temperature will tend to be stable, that is, Figure 2 the curve shown. For a connector with insufficient current-carrying capacity, since the connector cannot effectively conduct current, the heat generated by the resistance cannot be dissipated in time, resulting in a sharp rise in temperature. The temperature rise rate may remain at a relatively high level all the time, or may not be stable for a long time. The temperature-time change curve may show a continuous steep rise without any sign of flattening.

[0025] Among them, the number of copper bar energy storage connectors can be multiple, and the temperature data of the copper bar energy storage connectors under different currents are tested in sequence according to the method mentioned in the above embodiments of the present invention. Further, during the process of loading current, record the temperature changes of the copper bar energy storage connectors at the same moment under different current values, and closely observe the state of the connectors at the same time.

[0026] It should be noted that the temperature of the copper bar energy storage connectors is mainly measured using a high-precision temperature sensor, such as a thermocouple, which is attached to the key parts of the copper bar energy storage connectors. In the embodiments of the present invention, multiple thermocouples are used to measure the temperature of the copper bar energy storage connectors under different currents, and they are evenly distributed at the key parts of the copper bar energy storage connectors. The temperature data of the copper bar energy storage connectors under different currents are obtained according to the above steps.

[0027] S102. Determine the temperature anomaly parameter of the copper bar energy storage connector under the current according to the total duration of the temperature change of the copper bar energy storage connector under the current and the temperature data at each moment of the current.

[0028] Specifically, according to the analysis in the above embodiments of the present invention, the initial anomaly of the copper bar energy storage connector can be determined according to the characteristics of the temperature-time change curve of the copper bar energy storage connector under the same current.

[0029] Further, as an optional embodiment of the present invention, determining the temperature anomaly parameter of the copper bar energy storage connector under the current according to the total duration of the temperature change of the copper bar energy storage connector under the current and the temperature data at each moment of the current includes: determining the temperature change rate of the copper bar energy storage connector according to the total duration of the temperature change of the copper bar energy storage connector under the current, the last temperature data of the copper bar energy storage connector, and the first temperature data of the copper bar energy storage connector; taking the maximum value among the temperature change rates of all the copper bar energy storage connectors; determining the temperature data of the copper bar energy storage connector at the last N moments under the current, and calculating the second difference between the temperature data at adjacent moments among the N moments, where N is a natural number greater than or equal to 2; calculating the second average value of each second difference and the third average value of the third difference between each second difference; determining the temperature anomaly parameter of the copper bar energy storage connector under the current according to the temperature change rate, the maximum value, the second average value, and the third average value.

[0030] Specifically, in the embodiments of the present invention, N can take the value of 5. In the embodiments of the present invention, the temperature data corresponding to the last 5 moments are taken and denoted as comparison data, and the difference between it and the previous temperature data is calculated and denoted as . Among them, . … (n represents the number of comparison data, where n = 5 here), and four difference data of the comparison data are obtained accordingly, 、 , , . When the current-carrying capacity of the copper busbar energy storage connector is normal, its temperature will eventually tend to be consistent, so The smaller the value, and The difference between them will also be smaller. Denote the mean value of all as , and denote the mean value of the differences between all as . and The smaller the values, the smaller the difference between the comparison data, the more similar the comparison data, indicating that the temperature tends to be stable at the last moment, and the smaller the possibility of abnormality in the copper busbar energy storage connector.

[0031] Furthermore, as an optional embodiment of the present invention, according to the total duration of the temperature change of the copper busbar energy storage connector under current, the last temperature data of the copper busbar energy storage connector, and the first temperature data of the copper busbar energy storage connector, determining the temperature change speed of the copper busbar energy storage connector includes: calculating the fourth difference between the last temperature data and the first temperature data; determining the first ratio between the fourth difference and the total duration as the temperature change speed of the copper busbar energy storage connector.

[0032] Specifically, the embodiment of the present invention specifically calculates the temperature change speed of the copper busbar energy storage connector by the following formula: In the above formula, represents the temperature change speed of the mth copper busbar energy storage connector under any current. represents the total duration of the temperature change under this current, which is 10 minutes in the embodiments of the present invention. represents the last temperature data of the mth copper busbar energy storage connector. represents the first temperature data of the mth copper busbar energy storage connector. The greater the change in temperature data within a certain period of time, the faster its change speed, corresponding to The greater the value.

[0033] Furthermore, calculate the temperature change speeds of all copper busbar energy storage connectors under the same current, and determine the maximum value among them, which is denoted as in the embodiments of the present invention.

[0034] Furthermore, as an optional embodiment of the present invention, according to the temperature change speed, the maximum value, the second average value, and the third average value, determining the temperature anomaly parameter of the copper busbar energy storage connector under current includes: calculating the second ratio between the temperature change speed and the maximum value and the third product between the second average value and the third average value; determining the fourth product between the second ratio and the third product as the temperature anomaly parameter of the copper busbar energy storage connector under current.

[0035] Specifically, the embodiments of the present invention specifically calculate the temperature anomaly parameter of the copper bus energy storage connector under current by the following formula: In the above formula, represents the temperature anomaly parameter of m copper bus energy storage connectors under a certain current. represents the temperature change rate of the mth copper bus energy storage connector under any current. represents the maximum value among the temperature change rates of the mth copper bus energy storage connector under any current. The closer the value of is to 1, the closer the temperature change of the mth copper bus energy storage connector is to the maximum value, and the more abnormal its temperature is under the current current. represents the second average value. represents the third average value. represents the difference between the comparison data. When the temperature change rate is large and the difference between the comparison data is also large, it indicates that the temperature change of the mth copper bus energy storage connector is abnormal under the current current, and the mth copper bus energy storage connector may be abnormal.

[0036] S103. Determine the initial anomaly parameter of the copper bus energy storage connector according to the temperature anomaly parameter, the temperature data of the current copper bus energy storage connector and other copper bus energy storage connectors at the last moment.

[0037] Specifically, for copper bus energy storage connectors of the same batch, there may also be slight differences in raw materials, process precision during manufacturing, and differences in contact resistance, such as factors like the roughness and cleanliness of the contact surface and the mating precision of the connecting components. These factors will also affect the electrical performance of the copper bus energy storage connector, such as its current-carrying capacity. For example, during the assembly process, if there are tiny impurity particles on the contact surface that are not cleaned thoroughly, it will increase the contact resistance, resulting in the possibility that the temperature of connectors of the same batch under the same current may show significant differences.

[0038] Further, as an optional embodiment of the present invention, determining the initial anomaly parameter of the copper bus energy storage connector according to the temperature anomaly parameter, the temperature data of the current copper bus energy storage connector and other copper bus energy storage connectors at the last moment includes: calculating the fourth average value of the fifth difference between the temperature data of the current copper bus energy storage connector and other copper bus energy storage connectors at the last moment; calculating the fifth product of the fourth average value and the temperature anomaly parameter, and performing normalization processing on the fifth product to obtain the initial anomaly parameter of the copper bus energy storage connector.

[0039] Specifically, in the embodiment of the present invention, the difference between the temperature data of the m-th copper bus energy storage connector corresponding to the last moment in the temperature change duration and the temperature data of other copper bus energy storage connectors at the same current value is calculated and denoted as , ( represents the temperature data of the last moment of the m-th copper bus energy storage connector, represents the temperature data of the last moment of the p-th copper bus energy storage connector). The smaller the value of

[0040] , the smaller the overall difference between the two. In the above formula, represents the initial abnormal parameter of the m-th copper bus energy storage connector. represents the average value of the temperature differences between the m-th copper bus energy storage connector and all other copper bus energy storage connectors at the same current, that is, the fourth average value of the fifth difference. The larger the value of , the more abnormal the m-th copper bus energy storage connector is under the current. represents the temperature abnormal parameter of the m copper bus energy storage connectors at a certain current. represents the normalization function, which is used to normalize within the range of

[0041] S104. Determine the first abnormal feature before the temperature of the copper bus energy storage connector first appears abnormal according to the initial abnormal parameter.

[0042] Specifically, in the embodiment of the present invention, the initial abnormal parameters of each copper bus energy storage connector at different currents are calculated in the order of the magnitude of the current. In the embodiment of the present invention, a third threshold is preset. When the initial abnormal parameter is greater than or equal to the third threshold, it is determined that the temperature of the copper bus energy storage connector is abnormal at the current. When the initial abnormal parameter is less than the third threshold, it is determined that the temperature of the copper bus energy storage connector is normal at the current. Among them, the third threshold can be determined according to the actual situation, and the value in the embodiment of the present invention is 0.5 here.

[0043] Further, as an optional embodiment of the present invention, determining the first abnormal feature before the temperature of the copper bar energy storage connector first appears abnormal according to the initial abnormal parameter includes: when the initial abnormal parameter is greater than or equal to the third threshold, determining that the temperature of the copper bar energy storage connector is abnormal under the current; sorting all currents in ascending order and numbering them, and calculating the first variance of the initial abnormal parameters corresponding to all currents before the current when the temperature of the copper bar energy storage connector first appears abnormal; performing inverse proportional normalization processing on the first variance to obtain the normalized variance; determining that the sixth product between the number of the current when the temperature of the copper bar energy storage connector first appears abnormal and the first variance is the first abnormal feature before the copper bar energy storage connector first appears temperature abnormal.

[0044] Specifically, within the rated current-carrying capacity range specified for the energy storage connector, the temperature under different currents is also within the allowable temperature rise limit, and it can be considered that the current-carrying capacity meets the standard. If the temperature is abnormal within the allowable current range, it may be due to insufficient current-carrying capacity or problems with the assembly and connection of the copper bar energy storage connector during the test, resulting in poor contact and thus local overheating caused by poor contact. Therefore, for the current value with abnormal temperature, it is necessary to further analyze the change characteristics of its temperature when the current value continues to increase. Under normal circumstances, the performance of insufficient current-carrying capacity of the copper bar energy storage connector usually appears when approaching the rated current, rather than at the minimum current. When there is a situation of poor contact, the temperature will be abnormal regardless of the size of the current value. This embodiment starts measuring from a smaller current. Therefore, it is necessary to first analyze the current characteristics before the current with abnormal temperature appears.

[0045] Further, in the embodiment of the present invention, all currents are first sorted in ascending order from small to large and numbered. When the temperature of the copper bar energy storage connector first appears abnormal, the corresponding current number is denoted as , The larger the value of , the greater the current when the temperature first appears abnormal, the closer it is to the rated current, and the more likely it is that the temperature abnormal is caused by insufficient current-carrying capacity. Then, the variance of the initial abnormal parameters corresponding to all current values before the temperature appears abnormal is denoted as

[0046] The smaller the value of In the above formula, It represents the first abnormal feature before the temperature of the m-th copper bar energy storage connector first shows abnormality. It represents the current number corresponding to the first occurrence of temperature abnormality of the m-th copper bar energy storage connector. The larger the value, the later the first occurrence of temperature abnormality, the greater the corresponding current, and when all previous initial abnormalities are smaller, this temperature abnormality is more likely to be caused by insufficient current carrying. It represents the variance of the initial abnormal parameters corresponding to all current values before the temperature of the m-th copper bar energy storage connector shows abnormality. (-) is an inverse proportional normalization function, which is used to perform inverse proportional normalization processing on

[0047] Furthermore, for the m-th copper bar energy storage connector, after its temperature shows abnormality, continue to increase the current to test its temperature at other larger currents and record the temperatures at different currents.

[0048] S105, starting from the current at the first occurrence of abnormality, arrange the currents sorted after it in ascending order to obtain a current sequence, and use the temperature data at the last moment of each current in the current sequence as the temperature data of the copper bar energy storage connector at each current, so as to obtain a temperature sequence corresponding to the current sequence.

[0049] Specifically, in the embodiment of the present invention, starting from the current at which the temperature shows abnormality, arranging all subsequent currents in ascending order can obtain a current sequence. Here, all currents are within the rated current range of the copper bar energy storage connector, and the maximum value is the rated current. Use the last temperature data within the measurement time range of each current as the temperature data of the copper bar energy storage connector at that current, and thus a temperature sequence corresponding to the current sequence can be obtained.

[0050] S106, determine the possibility that the temperature abnormality of the copper bar energy storage connector is caused by insufficient current carrying capacity according to the first abnormal feature, the temperature sequence and the current sequence.

[0051] Specifically, under normal circumstances, as the current increases, the temperature of the copper busbar energy storage connector will also increase accordingly, but it will not exceed the temperature range of the copper busbar energy storage connector under normal working conditions. If there is a poor contact, a small change in current will cause a large change in the amount of heat generated, which will in turn cause the temperature to rise rapidly. Moreover, the temperature rise is mainly concentrated in the area with poor contact. When the current-carrying capacity of the copper busbar energy storage connector is insufficient, as the current increases, the temperature will continue to rise. Since the insufficient current-carrying capacity is due to the conductivity of the copper busbar itself (such as insufficient cross-sectional area, low conductivity of the material, etc.), the rate of temperature rise will be relatively gentle compared to the case of poor contact, and the temperature of the entire copper busbar energy storage connector will rise evenly, rather than being concentrated locally as in the case of poor contact.

[0052] Furthermore, as an optional embodiment of the present invention, the possibility that the temperature anomaly of the copper busbar energy storage connector is caused by insufficient current-carrying capacity determined according to the first anomaly feature, temperature sequence, and current sequence includes: calculating the second variance of the temperature data in the temperature sequence, and calculating the fifth average value of the second variance; drawing the current-temperature change curve of the copper busbar energy storage connector according to the temperature sequence and current sequence, and obtaining the slope of the current-temperature change curve; calculating the seventh product between the slope and the fifth average value, and performing inverse proportional normalization processing on the seventh product to obtain a normalized value; calculating the eighth product between the normalized value and the first anomaly feature; normalizing the eighth product to obtain the possibility that the temperature anomaly of the copper busbar energy storage connector is caused by insufficient current-carrying capacity.

[0053] Specifically, in the embodiment of the present invention, the variance of the temperature data of all thermocouples at the last moment of the temperature change time under each subsequent current of the copper busbar energy storage connector is calculated to represent the uniformity of the temperature distribution of the copper busbar energy storage connector. The smaller the variance, the more similar the temperatures of different key parts are, and the more uniform the temperature distribution is. Conversely, it indicates that the temperature is more uneven. Calculate the average value of the temperature variances under each current, that is, the second variance, which is denoted as in the embodiment of the present invention, and is used to represent the uniformity of the temperatures of all currents of the mth copper busbar energy storage connector. The larger the value of , the more uneven the temperature is, and the smaller the value, the more uniform the temperature is.

[0054] Furthermore, draw the current-temperature change curve (the horizontal axis is the current and the vertical axis is the temperature) of the copper busbar energy storage connector according to the current sequence and temperature sequence, which is used to represent the temperature change situation of the copper busbar energy storage connector at other current values after the temperature anomaly occurs, and obtain the slope of the current-temperature change curve. In the embodiment of the present invention, the slope of the mth copper busbar energy storage connector is denoted as . If the temperature anomaly is caused by poor contact, The value will be relatively large. If the temperature anomaly is caused by insufficient current-carrying capacity, the value will be relatively small.

[0055] Furthermore, in the embodiments of the present invention, the following formula is specifically used to calculate the possibility that the temperature anomaly of the copper bus energy storage connector is caused by insufficient current-carrying capacity: In the above formula, represents the possibility that the temperature anomaly of the m-th copper bus energy storage connector is caused by insufficient current-carrying capacity. represents the first abnormal feature before the m-th copper bus energy storage connector first exhibits a temperature anomaly. represents the slope of the current-temperature change curve of the m-th copper bus energy storage connector. represents the second variance of the temperature data in the temperature sequence of the m-th copper bus energy storage connector. (-) is an inverse proportional normalization function, which is used to perform inverse proportional normalization processing on represents a normalization function, which is used to perform normalization processing on and normalize it to the range of

[0056] S107. Determine the current-carrying performance of the copper bus energy storage connector according to the possibility.

[0057] Specifically, in the embodiments of the present invention, by presetting a first threshold, when the possibility is greater than the first threshold, it is considered that its current-carrying performance is insufficient; when the possibility is less than or equal to the first threshold, it is considered that its current-carrying performance is normal. For copper bus energy storage connectors with normal current-carrying capacity, in the embodiments of the present invention, the temperature change situation when they exceed the rated current is further analyzed to further determine their current-carrying performance. Among them, the first threshold can be determined according to the actual situation, and in the embodiments of the present invention, the value is 0.6.

[0058] Further, as an optional embodiment of the present invention, determining the current-carrying performance of the copper bus energy storage connector according to the possibility includes: when the possibility is greater than the first threshold, determining that the current-carrying performance of the copper bus energy storage connector is insufficient; when the possibility is less than or equal to the first threshold, determining that the current-carrying performance of the copper bus energy storage connector is normal; determining the copper bus energy storage connector with normal current-carrying performance as the target copper bus energy storage connector, starting from the current magnitude at the first time when the target copper bus energy storage connector has a temperature anomaly, increasing a predetermined value of the rated current each time, and measuring the first average value of the temperature data at the last moment during the temperature change time after each current increase; calculating the first difference between the first average value of each target copper bus energy storage connector and the temperature limit, marking the first difference greater than or equal to the second threshold as the first value, and marking the first difference less than the second threshold as the second value; arranging and numbering the first value and the second value in chronological order to obtain a numerical sequence; determining the current-carrying performance parameter of the target copper bus energy storage connector according to the target current data at the first time when the target copper bus energy storage connector has a temperature anomaly, the number of the first first value in the numerical sequence, the number of the first values, and the possibility of the target copper bus energy storage connector; determining the current-carrying performance of the target copper bus energy storage connector according to the current-carrying performance parameter.

[0059] Specifically, when designing the copper bus energy storage connector, there is usually a certain margin of current-carrying capacity. If the amplitude exceeding the rated current is within this margin, temperature anomalies may not occur immediately. Therefore, when the copper bus energy storage connector exceeds the rated current, temperature anomalies generally do not occur immediately, but only when it exceeds a certain amplitude (depending on factors such as the current-carrying capacity margin, heat dissipation conditions, material characteristics, and structural integrity), and after a period of heat accumulation, obvious temperature anomalies will occur. Therefore, for the connector with normal current-carrying capacity determined according to the temperature change within the rated current range in the above embodiment, it is also necessary to consider its temperature change outside the rated current range to determine its performance.

[0060] Among them, the current-carrying capacity margin of the copper bus energy storage connector is generally about 10%-20%. Therefore, for the connector with normal current-carrying performance determined in the above embodiment, it is denoted as the target copper bus energy storage connector. Starting from the magnitude of the current at the first time when the target copper bus energy storage connector has a temperature anomaly, a predetermined value of the rated current is increased each time, such as 2%, and increased 15 times. Measure the first average value of the temperature data of all thermocouples at the last moment during the temperature change time after each current increase. In the embodiment of the present invention, the first average value is denoted as .

[0061] Further, in the embodiment of the present invention, the second threshold can be set to 0. First, calculate the difference between each and its temperature limit, which is denoted as , When the value of is greater than 0, it indicates that the temperature at the current current exceeds the temperature limit. The larger the value of and the earlier it appears, it indicates that the temperature anomaly appears earlier, further indicating that the current-carrying performance of the target copper busbar energy storage connector is poor. On the contrary,

[0062] Further, the first numerical value can be taken as 1, and the second numerical value can be taken as 0. In the embodiment of the present invention, greater than or equal to 0 is recorded as 1, and less than 0 is

[0063] recorded as 0, arranged in chronological order to obtain a numerical sequence containing only 0 and 1, and numbered. The number of each digit represents its position. The smaller the number, the more forward the position.

[0064] Further, as an optional embodiment of the present invention, according to the target current data when the target copper busbar energy storage connector first shows a temperature anomaly, the number of the first numerical value in the numerical sequence, the number of the first numerical values, and the possibility of the target copper busbar energy storage connector, determining the current-carrying performance parameters of the target copper busbar energy storage connector includes: calculating the first product between the possibility of the target copper busbar energy storage connector and the number of the first numerical values, and performing inverse proportional normalization processing on the first product to obtain a normalized product; calculating the second product between the target current data, the number of the first numerical value, and the normalized product; performing normalization processing on the second product to obtain the current-carrying performance parameters of the target copper busbar energy storage connector. Specifically, the embodiment of the present invention specifically uses the following formula to calculate the current-carrying performance parameters of the target copper busbar energy storage connector: represents the current-carrying performance parameter of the xth target copper busbar energy storage connector. represents the current magnitude when the xth target connector first shows a temperature anomaly. The larger the value of , the later the first temperature anomaly appears, and the better the current-carrying performance. represents the number of all 1s in the numerical sequence of the xth target copper busbar energy storage connector. The larger the value of , the more times the temperature anomaly appears. represents the number of the first 1 in the numerical sequence of the xth target copper busbar energy storage connector. The smaller the value, the earlier the temperature anomaly appears, the more temperature anomalies there are, and the earlier the temperature anomaly appears, the worse the current-carrying performance. Indicates the probability that the temperature anomaly of the th target copper bus energy storage connector is caused by insufficient current-carrying capacity. (-) is an inverse proportional normalization function, which is used to perform inverse proportional normalization processing on normalize it to the range of

[0065] Further, when the current-carrying performance parameter of the target copper bus energy storage connector is within the range of , it is considered that its current-carrying performance is good and it can be used in any scenario. When the current-carrying performance parameter of the target copper bus energy storage connector is within the range of , it is considered that its current-carrying performance is qualified, and its usage range can be restricted to energy storage systems with relatively low current-carrying requirements and small current changes. When the current-carrying performance parameter of the target copper bus energy storage connector is within the range of , it is considered that its current-carrying performance is poor, and corresponding rectification or scrapping treatment needs to be carried out on the target copper bus energy storage connector to prevent potential safety hazards during its use.

[0066] The embodiments of the present invention can analyze the temperature data of the copper bus energy storage connector under different currents, obtain the temperature anomaly parameters of the copper bus energy storage connector under the current, and further determine the initial anomaly parameters of the copper bus energy storage connector according to the current temperature anomaly parameters of the copper bus energy storage connector and the temperature data of other copper bus energy storage connectors. Determine the first anomaly feature before the copper bus energy storage connector first appears a temperature anomaly according to the initial anomaly parameter, and further determine the probability that the temperature anomaly of the copper bus energy storage connector is caused by insufficient current-carrying capacity according to the first anomaly feature, temperature sequence, and current sequence, and determine the current-carrying performance of the copper bus energy storage connector according to this probability. In this way, the embodiments of the present invention combine the temperature data and current data of different copper bus energy storage connectors to test the current-carrying performance of the copper bus energy storage connector, improving the test accuracy of the current-carrying performance. Avoiding the influence of poor contact between the machine and the test equipment on the test results of the current and temperature of a certain copper bus energy storage connector improves the evaluation accuracy of the current-carrying performance of the copper bus energy storage connector.

[0067] It should be noted that: the above sequence of the embodiments of the present invention is only for description and does not represent the advantages or disadvantages 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.

[0068] ​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, and the key point of each embodiment is to illustrate the differences from other embodiments.

Claims

1. A method for testing the electrical performance of a copper bar energy storage connector, characterized in that, The electrical performance test method for the copper bus energy storage connector includes: Obtaining the temperature data of the copper bus energy storage connector under different currents; Determining the temperature anomaly parameter of the copper bus energy storage connector under the current according to the total duration of the temperature change of the copper bus energy storage connector under the current and the temperature data at each moment of the current; Determining the initial anomaly parameter of the copper bus energy storage connector according to the temperature anomaly parameter and the temperature data of the current copper bus energy storage connector and other copper bus energy storage connectors at the last moment; Determining the first anomaly feature of the copper bus energy storage connector before the first temperature anomaly according to the initial anomaly parameter; Starting from the current when the anomaly first occurs, arranging the currents sorted after it in ascending order to obtain a current sequence, and using the temperature data at the last moment of each current in the current sequence as the temperature data of the copper bus energy storage connector under each current, to obtain a temperature sequence corresponding to the current sequence; Determining the possibility that the temperature anomaly of the copper bus energy storage connector is caused by insufficient current-carrying capacity according to the first anomaly feature, the temperature sequence, and the current sequence; Determining the current-carrying performance of the copper bus energy storage connector according to the possibility.

2. The electrical performance testing method of the copper bus energy storage connector according to claim 1, characterized in that, The determining the current-carrying performance of the copper bus energy storage connector according to the possibility includes: When the possibility is greater than the first threshold, determining that the current-carrying performance of the copper bus energy storage connector is insufficient; when the possibility is less than or equal to the first threshold, determining that the current-carrying performance of the copper bus energy storage connector is normal; Determining the copper bus energy storage connector with normal current-carrying performance as the target copper bus energy storage connector, starting from the magnitude of the current when the target copper bus energy storage connector first has a temperature anomaly, increasing by a predetermined value of the rated current each time, and measuring the first average value of the temperature data at the last moment during the temperature change time after each current increase; Calculating the first difference between the first average value of each target copper bus energy storage connector and the temperature limit, marking the first difference greater than or equal to the second threshold as the first value, and marking the first difference less than the second threshold as the second value; Arranging and numbering the first value and the second value in chronological order to obtain a value sequence; Determining the current-carrying performance parameter of the target copper bus energy storage connector according to the target current data when the target copper bus energy storage connector first has a temperature anomaly, the number of the first first value in the value sequence, the number of the first values, and the possibility of the target copper bus energy storage connector; Determining the current-carrying performance of the target copper bus energy storage connector according to the current-carrying performance parameter.

3. The electrical performance test method for the copper bus energy storage connector according to claim 2, characterized in that, The determining the current-carrying performance parameter of the target copper bus energy storage connector according to the target current data when the target copper bus energy storage connector first has a temperature anomaly, the number of the first first value in the value sequence, the number of the first values, and the possibility of the target copper bus energy storage connector includes: Calculate a first product between the possibility of the target copper bus energy storage connector and the quantity of the first numerical value, and perform inverse proportional normalization processing on the first product to obtain a normalized product; Calculate a second product between the target current data, the serial number of the first first numerical value, and the normalized product; Perform normalization processing on the second product to obtain the current-carrying performance parameter of the target copper bus energy storage connector.

4. The electrical performance test method for the copper bar energy storage connector according to claim 1, wherein, The determining the temperature anomaly parameter of the copper bus energy storage connector under the current according to the total duration of the temperature change of the copper bus energy storage connector under the current and the temperature data at each moment of the current includes: Determine the temperature change rate of the copper bus energy storage connector according to the total duration of the temperature change of the copper bus energy storage connector under the current, the last temperature data of the copper bus energy storage connector, and the first temperature data of the copper bus energy storage connector; Take the maximum value among the temperature change rates of all the copper bus energy storage connectors; Determine the temperature data of the copper bus energy storage connector at the last N moments under the current, and calculate a second difference between the temperature data at adjacent moments among the N moments, where N is a natural number greater than or equal to 2; Calculate a second average value of each of the second differences and a third average value of a third difference between each of the second differences; Determine the temperature anomaly parameter of the copper bus energy storage connector under the current according to the temperature change rate, the maximum value, the second average value, and the third average value.

5. The electrical performance test method for the copper bar energy storage connector according to claim 4, characterized in that, The determining the temperature change rate of the copper bus energy storage connector according to the total duration of the temperature change of the copper bus energy storage connector under the current, the last temperature data of the copper bus energy storage connector, and the first temperature data of the copper bus energy storage connector includes: Calculate a fourth difference between the last temperature data and the first temperature data; Determine that a first ratio between the fourth difference and the total duration is the temperature change rate of the copper bus energy storage connector.

6. The electrical performance test method for the copper bar energy storage connector according to claim 4, characterized in that, The determining the temperature anomaly parameter of the copper bus energy storage connector under the current according to the temperature change rate, the maximum value, the second average value, and the third average value includes: Calculate a second ratio between the temperature change rate and the maximum value and a third product between the second average value and the third average value; Determine that a fourth product between the second ratio and the third product is the temperature anomaly parameter of the copper bus energy storage connector under the current.

7. The electrical performance test method for the copper bus energy storage connector according to claim 1, characterized in that, The determining the initial anomaly parameter of the copper bus energy storage connector according to the temperature anomaly parameter, the temperature data of the current copper bus energy storage connector and other copper bus energy storage connectors at the last moment includes: Calculate a fourth average value of a fifth difference between the temperature data of the current copper bus energy storage connector and other copper bus energy storage connectors at the last moment; Calculate a fifth product between the fourth average value and the temperature anomaly parameter, and perform normalization processing on the fifth product to obtain the initial anomaly parameter of the copper bus energy storage connector.

8. The method for testing the electrical performance of the copper bar energy storage connector according to claim 1, wherein The first abnormal feature before the first temperature anomaly of the copper bus energy storage connector determined according to the initial abnormal parameter includes: When the initial abnormal parameter is greater than or equal to the third threshold, it is determined that the temperature of the copper bus energy storage connector is abnormal under the current; All currents are sorted in ascending order and numbered, and the first variance of the initial abnormal parameters corresponding to all currents before the current when the temperature of the copper bus energy storage connector first appears abnormal is calculated; The inverse proportional normalization process is performed on the first variance to obtain the normalized variance; It is determined that the sixth product between the number of the current when the temperature of the copper bus energy storage connector first appears abnormal and the first variance is the first abnormal feature before the first temperature anomaly of the copper bus energy storage connector.

9. The electrical performance test method of the copper bus energy storage connector according to claim 1, characterized in that, The possibility that the temperature anomaly of the copper bus energy storage connector is caused by insufficient current-carrying capacity determined according to the first abnormal feature, the temperature sequence, and the current sequence includes: Calculate the second variance of the temperature data in the temperature sequence and calculate the fifth average value of the second variance; Draw the current-temperature change curve of the copper bus energy storage connector according to the temperature sequence and the current sequence, and obtain the slope of the current-temperature change curve; Calculate the seventh product between the slope and the fifth average value, and perform the inverse proportional normalization process on the seventh product to obtain the normalized value; Calculate the eighth product between the normalized value and the first abnormal feature; Normalize the eighth product to obtain the possibility that the temperature anomaly of the copper bus energy storage connector is caused by insufficient current-carrying capacity.

10. The electrical performance test method for the copper bus energy storage connector according to claim 1, characterized in that, The second threshold is 0.

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