Method and device for testing direct-current large-current power supply

Abstract

The invention relates to the technical field of direct-current large-current power supply testing, in particular to a direct-current large-current power supply testing method and device. According to the invention, temperature, voltage and current are synchronously acquired through multiple channels, and data validity is marked; after smoothing processing, calculating compensation resistance by using a two-item temperature compensation formula; according to current characteristics, an abnormal threshold value is dynamically adapted in a current increasing / stabilizing / decreasing period, and a normal / early warning / shutdown instruction is output in a grading manner; performing correlation analysis on temperature-resistance and voltage-current characteristics to identify hidden defects; the weighted linear regression predicts future temperature / resistance and gives an early warning; data are stored in a layered mode, visualized display is achieved, and a report containing A / B / C grade rating is automatically generated. The device comprises a corresponding functional unit and a processor-memory architecture, and is suitable for large-current testing of multi-scene electrical equipment.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of direct current large current power supply test, in particular to a test method and device of direct current large current power supply. BACKGROUND

[0002] The direct current large current power supply test refers to a professional test of outputting controllable direct current large current to a test product under short-time or intermittent operation mode, verifying the performance, safety and stability of the test product under large current working condition, and being applied to power plants, power distribution stations, electric appliance manufacturing plants and research laboratories, etc. scenes, and being used for debugging and detecting circuit breakers, cables, current transformers, etc. test products. In the test process, the current stability of the electrical equipment under the rated direct current large current (the maximum output DC1000A of the system) is detected to determine whether the conductor overheats, the insulation is damaged, etc. due to excessive current; for the current transformer, different levels of direct current are output to calibrate the ratio error and angle error to ensure that the measurement accuracy meets the standard; the overload, short circuit and other fault current scenarios of the test product are simulated to verify the action accuracy and response speed of the protection device (such as circuit breaker tripping and overcurrent shutdown); the temperature and voltage data of the test product are synchronously collected to calculate the resistance change and evaluate the thermal stability and conductive performance change trend of the test product under large current.

[0003] However, if the resistance of the test product is calculated by "R=U / I" without considering that the resistance of the test product (such as copper core cable and copper contact) changes significantly with temperature, the resistance calculation error will exceed 10% without temperature compensation, which cannot reflect the real conductive performance of the test product. In addition, for example, the conventional fixed threshold value for determining abnormality is "voltage difference>1V, current difference>5A", which does not consider the difference between the test stage (such as the current rise period and the current stabilization period) and the target current, and the fixed threshold value is easy to trigger the protection; the current in the current stabilization period should be stable, and the threshold value should be more strict, resulting in "loose or tight" abnormality determination. SUMMARY

[0004] In view of the above problems, there is an urgent need for a test method and device of direct current large current power supply with precision and foresight.

[0005] In a first aspect, the present application provides a test method of direct current large current power supply, comprising:

[0006] Obtaining a plurality of temperature information, a plurality of voltage information and a plurality of current information of the test product to form an original data set, the original data set comprising a plurality of information, each information recording a test product number, a time stamp, a temperature corresponding to the time stamp, a current corresponding to the time stamp and a voltage corresponding to the time stamp, wherein the temperature corresponding to the time stamp has a valid or invalid mark, the current corresponding to the time stamp has a valid or invalid mark, and the voltage corresponding to the time stamp has a valid or invalid mark;

[0007] remove the data with invalid mark in the original data set, call a two-item temperature compensation formula according to a preset temperature coefficient of the test material, calculate a compensation resistance corresponding to each timestamp, and obtain a compensation resistance data set;

[0008] determine that the current test stage is in a current increasing period, a current stable period or a current decreasing period according to the multiple currents with valid marks and the target current set by the user, and output a stage mark with one of the current increasing period, the current stable period and the current decreasing period; call a corresponding formula to calculate abnormality determination thresholds of the current, the temperature and the voltage based on the current test stage, and output a test normal instruction, a pre-warning instruction or a shutdown instruction according to the abnormality determination result;

[0009] determine the correlation rationality of the temperature data and the resistance data of the test sample and the stability of the resistance data, and obtain a correlation analysis result;

[0010] predict a predicted temperature and a predicted resistance of a future prediction time interval according to the temperature data and the compensation resistance data of multiple timestamps before the current timestamp, and output a prediction result;

[0011] store and display the valid data set, the compensation resistance data, the abnormality determination result, the abnormality log, the correlation analysis result, the prediction result and the user-set record interval;

[0012] output a test report containing the valid data set, the compensation resistance data set, the abnormality determination result, the correlation analysis result and the prediction result, and the test report contains test analysis ratings A, B and C, the A rating indicates no abnormality, the B rating indicates a pre-warning, and the C rating indicates triggering of shutdown.

[0013] In a second aspect, the present application provides a test device for a direct-current large-current power supply, comprising:

[0014] a data acquisition unit configured to acquire multiple temperature information, multiple voltage information and multiple current information of a test sample, and form an original data set, wherein the original data set comprises multiple information items, each information item records a test sample number, a timestamp, a temperature corresponding to the timestamp, a current corresponding to the timestamp and a voltage corresponding to the timestamp, wherein the temperature corresponding to the timestamp is marked with a valid or invalid mark, the current corresponding to the timestamp is marked with a valid or invalid mark, and the voltage corresponding to the timestamp is marked with a valid or invalid mark;

[0015] a data preprocessing and compensation unit configured to remove the data with invalid mark in the original data set, call a two-item temperature compensation formula according to a preset temperature coefficient of the test material, calculate a compensation resistance corresponding to each timestamp, and obtain a compensation resistance data set;

[0016] The dynamic abnormality judging unit is used for determining that the current test stage is in the current increase period, the current stable period or the current decrease period according to the current and the target current set by the user with the effective mark, and outputting the stage mark with one of the current increase period, the current stable period and the current decrease period; based on the current test stage, calling the corresponding formula to calculate the abnormality judging threshold of the current, the temperature and the voltage, and outputting the test normal instruction, the early warning instruction or the shutdown instruction according to the abnormality judging result;

[0017] The correlation judging unit is used for judging the correlation rationality of the temperature data and the resistance data of the test sample and the stability of the resistance data, and obtaining the correlation analysis result;

[0018] The trend predicting unit is used for predicting the predicted temperature and the predicted resistance of the future prediction time interval according to the temperature data and the compensated resistance data of a plurality of time stamps before the current time stamp, and outputting the prediction result;

[0019] The data storage and display unit is used for storing and displaying the effective data set, the compensated resistance data, the abnormality judging result, the abnormality log, the correlation analysis result, the prediction result and the user setting record interval.

[0020] The output unit is used for outputting the test report containing the effective data set, the compensated resistance data set, the abnormality judging result, the correlation analysis result and the prediction result, and the test report contains the test analysis rating A, B and C, the A grade indicates no abnormality, the B grade indicates early warning, and the C grade indicates triggering shutdown.

[0021] In a third aspect, the application provides a test device for a direct current large current power supply, comprising a processor and a memory; wherein the memory is used for storing a computer program, the computer program is loaded and executed by the processor to realize the test method of the first aspect.

[0022] Advantages:

[0023] The test method and device for the direct current large current voltage provided by the application adopt multi-channel data acquisition, automatically mark invalid data, the test sample state evaluation is more comprehensive, and the data quality is significantly improved. The method and device adopt double temperature compensation, so that the resistance error is less than or equal to 2%, the real conductive performance of the test sample is accurately reflected, and the temperature interference problem is solved.

[0024] The dynamic threshold value obtained by the application can be used to judge real-time exceptions, is an ''immediate exception judgment standard'' based on dynamic calculation of a test phase (flow increase period / flow stabilization period / flow decrease period) and a target current (Iset), and is directly used as a basis for triggering ''immediate early warning (sound and light prompt) or shutdown protection''. During the test, the temperature (Tt), voltage (Ut) and current (It) collected in real time are compared with the dynamic threshold value every second, and if the three parameters exceed the threshold value continuously for 3 seconds (for example, the current fluctuation exceeds DIth=Ise*0.02 during the flow stabilization period), immediate disposal (first early warning, and shutdown if the parameters are not restored within 10 seconds) is started, which belongs to the category of ''real-time error prevention''. The dynamic threshold value is adapted to the test phase, avoids misjudgment / misjudgment, reduces invalid test interruption, and improves the accuracy of abnormal judgment by 80%.

[0025] The application determines the temperature coefficient deviation rate according to the supplementary resistance data, corresponding temperature data and material standard temperature coefficient of the test sample, determines the rationality of the relationship between the temperature and the resistance according to the temperature coefficient deviation rate, determines the coefficient of variation according to the voltage data of the effective data set and the current data during the flow stabilization period, and judges the resistance stability of the test sample according to the coefficient of variation. Through multi-parameter correlation analysis, hidden problems such as oxidation and poor contact can be found, and the test sample with hidden dangers can be avoided from being delivered, and the identification ability of hidden defects is strengthened.

[0026] The early warning threshold provided by the application is an early warning standard for short-term trend prediction, combines future 1-minute temperature (Tpred) and resistance (Rpred), and sets ''advance risk prompt standard'' in combination with system protection limit value (such as protection temperature 80 DEG C), and is used as a basis for triggering ''advance intervention suggestion''. This step takes ''system protection limit value (such as DEG C)'' as the basis, reserves a safety buffer space (such as 90% of the protection value), and sets the resistance early warning threshold (Rpred>1.1*Ravg) in combination with the average resistance (Ravg) of the previous 10 minutes, which has a prediction attribute. The application realizes risk early warning, and users can actively adjust the test parameters (such as flow decrease), improve the test safety and the survival rate of the test sample, and reduce the damage rate of the test sample by more than 60%.

[0027] The application realizes real-time judgment of exceptions based on the dynamic threshold value, and short-term prediction of trends based on the early warning threshold. The dynamic threshold value and the judgment step thereof provide a basic protection value and effective data for short-term trend prediction, and the early warning threshold and the judgment step thereof avoid triggering the shutdown risk of the dynamic threshold value in advance. Through ''homologous basis, data dependence and function cooperation'', the two realize double protection of ''real-time exception disposal'' and ''future risk prediction'' of the system, which not only guarantees the test safety, but also improves the survival rate of the test sample and the test efficiency.

[0028] The application stores and displays the effective data set, compensation resistance data, abnormality determination result, abnormality log, correlation analysis result, prediction result and user setting record interval, and automatically generates a standard report and rating through automatic generation of a test report, greatly reduces the manual workload, supports rapid determination, and improves the report efficiency by 90%. BRIEF DESCRIPTION OF DRAWINGS

[0029] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or prior art description will be briefly introduced. Obviously, the drawings in the following description are only embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor on the basis of the provided drawings.

[0030] Figure 1 It is a flowchart of the test method of the direct current large current power supply.

[0031] Figure 2 It is a flowchart of step S10.

[0032] Figure 3 It is a flowchart of step S20.

[0033] Figure 4 It is a flowchart of step S30.

[0034] Figure 5 It is a flowchart of step S33.

[0035] Figure 6 It is a flowchart of step S40.

[0036] Figure 7 It is a flowchart of step S41.

[0037] Figure 8 It is a flowchart of step S42.

[0038] Figure 9 It is a flowchart of step S50.

[0039] Figure 10 It is a flowchart of step S52.

[0040] Figure 11 It is a flowchart of step S53.

[0041] Figure 12 It is a logic structure schematic diagram of the test device of the direct current large current power supply.

[0042] Figure 13 It is a logic structure schematic diagram of another test device of the direct current large current power supply. DETAILED DESCRIPTION

[0043] In order to make the purposes, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present application.

[0044] Relying on a direct current large current power supply system (for example, a current riser), input AC380V, output DC0-1000A, rated capacity 30KVA, adapting to 30-way thermocouple temperature probes (green and blue lines), 30-way voltage probes (red and black lines), a temperature inspection instrument and a direct current output source hardware, in order to realize intelligent processing of temperature, voltage and current data in a whole process of testing, the present application provides a test method for a direct current large current power supply. As shown in the figure, the method comprises: Figure 1

[0045] Step S10: obtaining multiple temperature information, multiple voltage information and multiple current information of a test sample, forming an original data set, the original data set comprising multiple information items, each information item recording a test sample number, a time stamp, a temperature corresponding to the time stamp, a current corresponding to the time stamp and a voltage corresponding to the time stamp, wherein the temperature corresponding to the time stamp is marked with an effective or ineffective mark, the current corresponding to the time stamp is marked with an effective or ineffective mark, and the voltage corresponding to the time stamp is marked with an effective or ineffective mark;

[0046] Step S20: removing data with ineffective marks in the original data set, calling a two-item temperature compensation formula according to a preset temperature coefficient of a test sample material, calculating a compensation resistance corresponding to each time stamp, and obtaining a compensation resistance data set;

[0047] Step S30: determining that a current test stage is in a current rising period, a current stable period or a current falling period according to multiple currents with effective marks and a user-set target current, outputting a stage mark with one of the current rising period, the current stable period and the current falling period; calling a corresponding formula to calculate abnormality judgment thresholds of current, temperature and voltage based on the current test stage, and outputting a test normal instruction, a pre-warning instruction or a shutdown instruction according to an abnormality judgment result;

[0048] Step S40: judging correlation rationality between temperature data and resistance data of a test sample and stability of resistance data, and obtaining a correlation analysis result;

[0049] Step S50: predicting a predicted temperature and a predicted resistance in a future prediction time interval according to temperature data and compensation resistance data of multiple time stamps before a current time stamp, and outputting a prediction result.​

[0050] Step S60: store and display the effective data set, the compensation resistance data, the abnormality determination result, the abnormality log, the correlation analysis result, the prediction result and the user setting record interval;

[0051] Step S70: output a test report containing the effective data set, the compensation resistance data set, the abnormality determination result, the correlation analysis result and the prediction result, the test report containing test analysis ratings A, B and C, the A rating indicating no abnormality, the B rating indicating a warning and the C rating indicating triggering a shutdown.

[0052] To implement step S10, multiple data synchronous acquisition is performed, 30 temperature probes are arranged at key points of the test product and the test chamber according to the correspondence between the 1-30 channels and the identifiers, 30 voltage probes correspond to the 1-30 channels and are connected in parallel at both ends of the test product, the temperature inspection instrument and the industrial computer are connected, the direct current output source and the industrial computer are connected, and the communication link is verified. The correspondence between the "physical probe" and the "software data channel" is established through hardware wiring, and if the communication timeout is greater than 3 seconds, it is marked as "channel abnormality", so as to ensure the effectiveness of the subsequent data acquisition link and avoid data loss caused by probe connection error or communication interruption, and to provide accurate "data-position" correspondence for subsequent data processing.

[0053] The test system collects data at a fixed frequency, the temperature inspection instrument collects 30 channels of temperature data at 1 second / second, the voltage probe collects 30 channels of voltage data through the analog input module at 1 second / second, the direct current output source collects output current data at 0.5 second / second, and all data is attached with a millisecond level timestamp.

[0054] Specifically, step S10 includes:

[0055] S11: obtaining real-time temperature, real-time voltage and output real-time current of multiple channels of the test product, and obtaining an original data set after processing, the original data set including multiple information items, each information item recording test product number, timestamp, temperature corresponding to the timestamp, current corresponding to the timestamp and voltage corresponding to the timestamp;

[0056] In this way, the system obtains real-time temperature, real-time voltage and output real-time current of the test product, and obtains a timestamped original data set after processing, for example, each information item records in the format of [test number, timestamp, T1-T30, U1-U30, I], T=temperature, U=voltage and I=current. Through hardware timing sampling, the physical quantity (temperature, voltage and current) is converted into a digital signal, and is synchronized according to the "timestamp alignment" rule (for example, the current data is 0.5 second / second, the average value of the adjacent two times is taken, and the temperature and voltage data of 1 second / second are aligned), so as to realize the synchronous alignment conversion of analog and digital quantities;

[0057] S12: judging whether the data in each channel in the original data set is continuous according to the parameter range;

[0058] S13: if no data for 3 seconds continuously or the data exceeds the parameter range is detected, assigning the original data set of the channel to an invalid mark and outputting a channel failure log;

[0059] S14: if no data for 3 seconds continuously or the data exceeding the parameter range is not detected, assigning the original data set of the channel to a valid mark.

[0060] Specifically, the invalid mark and the valid mark can be different assignments in the data set, or external alarm prompts, such as channel data anomaly prompts or alarm information directly displayed on a human-machine interface. The format of the channel failure log is [timestamp, channel number, failure type (no data / over range)].

[0061] In one embodiment, the parameter range is -50℃~300℃ for temperature, 0~10V for voltage, and 0~1000A for current.

[0062] Through steps S12-S14, the probe failure or data anomaly can be identified in advance, invalid data can be avoided from mixing into subsequent calculation, and error analysis conclusion can be reduced.

[0063] Specifically, step S20 includes:

[0064] Step S21: removing the original data set of the channel with the invalid mark, and performing smoothing processing on the original data set of the channel with the valid mark to obtain a valid data set;

[0065] Specifically, the smoothing processing is to take the average value of three times of collected parameters according to the time stamp, so as to eliminate accidental fluctuations, for example, to reduce the jump data caused by instantaneous poor contact of the probe, and the format of the valid data set is [timestamp, T1~T30 (valid), U1~U30 (valid), I (valid)].

[0066] Step S22: obtaining the original resistance of multiple channels in the valid data set and the corresponding real-time temperature, and determining the compensation resistance corresponding to the original resistance of the multiple channels according to the first temperature coefficient and the second temperature coefficient of the test material, wherein the first temperature coefficient is the temperature coefficient of the material at 20℃, reflecting the linear influence of temperature on the resistance of the material, and the second temperature coefficient is the nonlinear influence of temperature on the material at 20℃;

[0067] Specifically, the compensation resistance is determined according to Rraw is the original resistance, Rt,comp is the compensation resistance (mΩ), α is the first temperature coefficient of the material, β is the second temperature coefficient, Tt is the real-time temperature of the test product (℃). Copper: α=0.00393 / ℃, β=0.00000577 / ℃²; aluminum: α=0.00429 / ℃, β=0.0000048 / ℃². For example, when the copper test product Tt=35℃, Ut=0.3V, It=500A, Rraw=0.6mΩ, Rt,comp=0.6 / [1+0.00393×15+0.00000577×15 2 =0.566mΩ, the error is reduced from 10% to ≤2%. After this step, the influence of temperature on resistance can be eliminated, the resistance calculation error is reduced from 10% to ≤2% of the traditional method, and the real conductive performance of the test product is accurately reflected.

[0068] The specific step S30 includes:

[0069] Step S31: According to the current with effective mark and user set target current, determine the current test stage is in the current rise period, steady current period or current drop period, output the stage mark with one of the current rise period, steady current period and current drop period;

[0070] Specifically, according to the change trend formed by the current with effective mark and the user set target current, the circuit change trend is automatically divided into current rise period, steady current period and current drop period, for example, the period from 0 to the user set target current is the current rise period, the period that the current is maintained at the user set target current is the steady current period, and the period that the current is reduced from the user set target current to 0 is the current drop period.

[0071] In order to determine the time period of the current test stage, step S31 further includes: if it is detected that the real-time current It satisfies the condition It

[0072] Step S32: Based on the current test stage, call the corresponding threshold formula to calculate the abnormal judgment threshold of current, temperature and voltage, and generate a dynamic threshold set including current threshold, temperature threshold and voltage threshold.

[0073] Specifically, if the current test phase is in the rising flow period or the falling flow period, the dynamic current threshold is determined according to the dynamic temperature threshold is 5℃, allowing a larger fluctuation, and the larger the fluctuation, the larger the threshold; wherein, I(t-1) is the real-time current of the previous 1s;

[0074] If the current test phase is in the steady flow period, the dynamic current threshold is determined according to ΔIth=Iset×0.02, and the dynamic temperature threshold is 2℃, that is, only ±2% fluctuation is allowed;

[0075] The dynamic voltage threshold is determined according to ΔUth=Uavg×0.05, allowing ±5% fluctuation, wherein Uavg is the average value of the voltage data of a single channel.

[0076] In this way, the dynamic threshold is constructed, which adapts to the data characteristics of each stage, improves the accuracy of abnormal judgment, and reduces invalid test interruption. For example, in the steady flow period of Iset=500A, ΔIth=500×0.02=10A, that is, the current fluctuation exceeds 10A to trigger the abnormal early warning instruction.

[0077] Step S33: Based on the dynamic threshold in the dynamic threshold set, it is judged whether there is abnormal data in the effective data set, the compensation resistance data and the system protection temperature, and the abnormal judgment result and the abnormal log are output, the abnormal judgment result includes normal test instruction, abnormal early warning instruction or shutdown instruction, the abnormal log contains time stamp and abnormal type information, the normal test instruction is used to control the test process to continue, the abnormal early warning instruction is used to produce abnormal early warning information, and the shutdown instruction is used to control the test hardware to reduce flow and shutdown;

[0078] Specifically, step S33 includes:

[0079] Step S331: If it is detected that the real-time current of 3s satisfies |It-I(t-1)|>ΔIth for 3s, an abnormal early warning instruction is output; if the real-time current is not restored within 10s, a shutdown instruction is output;

[0080] Step S332: If it is detected that the real-time temperature satisfies |Tt-T(t-1)|>ΔTth or Tt>Tprot(80℃), a shutdown instruction is output, wherein T(t-1) is the real-time temperature of the previous 1s, and Tprot(80℃) is the system protection temperature;

[0081] Step S333: If it is detected that the real-time voltage of 3s satisfies |Ut-U(t-1)|>ΔUth, an abnormal early warning instruction is output; if the real-time voltage is not restored within 10s, a shutdown instruction is output;

[0082] The boundary condition of "3 consecutive seconds" avoids misjudgment due to instantaneous interference, while the "10-second recovery time" provides a window for manual intervention. This step enables tiered handling of early warning, intervention, and shutdown, ensuring the safety of the test samples while reducing test interruptions caused by minor fluctuations.

[0083] The dynamic threshold obtained in this step can be used to judge real-time anomalies. It is a "real-time anomaly judgment standard" dynamically calculated based on the test phase (current rise / steady-state / current fall) and the target current (Iset). Its core purpose is to monitor whether the current data exceeds the normal fluctuation range in real time, and it is the direct basis for triggering "real-time warning (audio-visual prompt) or shutdown protection". During the test, the real-time collected temperature (Tt), voltage (Ut), current (It) are compared with the dynamic threshold every second. If the threshold is exceeded for 3 consecutive seconds (e.g., the current fluctuation during the steady-state period exceeds ΔIth=Iset×0.02), the real-time handling is immediately initiated (first warning, then shutdown if it does not recover within 10 seconds), which falls under the category of "real-time error prevention".

[0084] The specific steps S40 include: Step S41: Determine the temperature coefficient deviation rate based on the supplementary resistance data, corresponding temperature data, and the material standard temperature coefficient of the sample, and determine the rationality of the correlation between temperature and resistance based on the temperature coefficient deviation rate; Step S42: Determine the coefficient of variation based on the effective dataset voltage data and the current data during the steady-state period, and determine the resistance stability of the sample based on the coefficient of variation.

[0085] Specifically, step S41 includes:

[0086] Step S411: Obtain supplementary resistance data, corresponding temperature data, and the material standard temperature coefficient of the sample, according to the formula. Determine the actual temperature coefficient, where Rt1,comp is the supplementary resistance at time t1, Rt2,comp is the supplementary resistance at time t2, and T... t1 Let T be the real-time temperature at time t1. t2 Let α be the real-time temperature at time t2. act This is the actual temperature coefficient;

[0087] Step S412: According to the formula Determine the temperature coefficient deviation rate, α std δα is the material standard temperature coefficient of the sample (e.g., 0.00393 / ℃ for copper, which is an empirical or test value), and δα is the temperature coefficient deviation rate.

[0088] Step S413: If the detected temperature coefficient deviation rate does not exceed 5%, output a signal indicating normal correlation, indicating that the sample material characteristics meet the standard;

[0089] Step S414: If the temperature coefficient deviation rate exceeds 5%, output a signal indicating an associated abnormality, indicating that the test product may have hidden defects such as oxidation or poor contact.

[0090] For example, the copper test product R(t1, comp) = 0.566 mΩ (T1 = 35°C), R(t2, comp) = 0.6 mΩ (T2 = 58°C), α act = (0.6-0.566) / (0.566×23)=0.00389 / ℃, δα=|0.00389-0.00393| / 0.00393×100%=1.02%≤5%, normal.

[0091] Specifically, step S42 includes:

[0092] Step S421: Obtain the effective data set voltage data and the current data during the constant current period, and determine the original real-time resistance according to the formula Kt = Ut / It, Kt is the original real-time resistance, It is the original real-time current, and Ut is the original real-time voltage;

[0093] Step S422: Determine the coefficient of variation CV U / I = σK / μK×100% according to the formula CV U / I , σK is the standard deviation of the original real-time resistance in the first 10 seconds, and μK is the average value of the original real-time resistance in the first 10 seconds;

[0094] Step S423: If the coefficient of variation is detected to be less than 3%, output a signal indicating that the resistance of the test product is stable, indicating that the voltage and current are associated normally;

[0095] Step S424: If the coefficient of variation is detected to be greater than 3%, output a signal indicating that the resistance of the test product is unstable, indicating that the voltage and current are associated abnormally (for example, caused by poor contact);

[0096] In this way, the contact state of the test product is reflected by the resistance fluctuation, and potential problems affecting the through-flow performance are discovered in a timely manner.

[0097] The specific step S50 includes: step S51: performing weighted processing on the temperature data and resistance data corresponding to multiple time stamps before the current time stamp; step S52: obtaining a predicted temperature of a future prediction time interval according to the temperature weight data set, and obtaining a predicted resistance of the future prediction time interval according to the resistance weight data set; step S53: comparing the predicted temperature with the future temperature warning threshold, comparing the predicted resistance with the future resistance warning threshold, and determining whether to output an early risk prompt.

[0098] In the specific step S51, temperature data (T1~T10, T10) and compensation resistance data (R1~R10) of a plurality of time stamps before the current time stamp are obtained, and after weighted processing, a temperature weight data set (Tw1~Tw10) and a resistance weight data set (Rw1~Rw10) are obtained. The weighted coefficient formula is , m is the number of a plurality of time stamps before the current time stamp, for example, 10 can be taken for 10s, i is 1~10, for example, i=10 (the latest data) weight , , the influence of recent data is amplified, and the interference of long-term data on the trend is avoided, so that the prediction result is more consistent with the current test state.

[0099] Specifically, the step S52 includes:

[0100] Step S521: Linear regression is performed on the temperature weight data set configured with temperature weights to obtain a temperature linear equation between the predicted temperature and the number of a plurality of time stamps before the current time stamp, and the slope of the temperature linear equation is determined according to , and the intercept of the temperature linear equation is determined by ; wherein m is the number of a plurality of time stamps before the current time stamp, i is any positive integer between 1 and m, T i is the i th temperature data, and w i is the temperature weight of the i th temperature data;

[0101] Step S522: Predicting the predicted temperature of the future prediction time interval according to the temperature linear equation;

[0102] Step S523: Linear regression is performed on the resistance weight data set configured with resistance weights to obtain a resistance linear equation between the predicted resistance and the number of a plurality of time stamps before the current time stamp, and the slope of the resistance linear equation is determined according to , and the intercept of the temperature linear equation is determined by ; wherein m is the number of a plurality of time stamps before the current time stamp, i is any positive integer between 1 and m, R i is the i th resistance data, and w i is the temperature weight of the i th resistance data;

[0103] Step S524: Predicting the predicted resistance of the future prediction time interval according to the resistance linear equation.

[0104] For example, the temperature linear equation is , the prediction time k is 1 minute, a=0.5℃ / s, b=50℃, and then Tpred=0.5×11+50=55.5℃.

[0105] Through this step, the temperature data and the resistance data change trend can be grasped in advance, a time window is provided for manual intervention, and the test sample is prevented from being damaged due to over-limit.

[0106] Specifically, step S53 comprises:

[0107] Step S531: Obtain a predicted temperature and a future temperature warning threshold, the future temperature warning threshold being a system protection temperature, and if it is detected that the predicted temperature is greater than 0.9 times the future temperature warning threshold, output a temperature advance risk warning signal;

[0108] Step S532: Obtain a predicted resistance and a future resistance warning threshold, the future resistance warning threshold being a plurality of resistance average values corresponding to a plurality of time stamps before the current time stamp, and if it is detected that the predicted resistance is greater than 1.1 times the future resistance warning threshold, output a resistance advance risk warning signal.

[0109] Specifically, this step realizes risk advance warning, the user can actively adjust the test parameters (such as reducing the flow), and improves the test safety and the survival rate of the test sample.

[0110] The warning threshold provided in this step is an advance warning standard of short-term trend prediction, combined with the future 1-minute temperature (Tpred) and resistance (Rpred), combined with the “advance risk prompt standard” set by the system protection limit value (such as the protection temperature 80℃), the core is used to predict whether the future data is close to the protection limit value, which is the basis for triggering the “advance intervention suggestion”. This step takes the “system protection limit value (such as ℃)” as the basis, reserves a safety buffer space (such as taking 90% of the protection value), and at the same time sets the resistance warning threshold (Rpred>1.1×Ravg) combined with the average resistance (Ravg) of the previous 10 minutes, which has a prediction attribute.

[0111] When the dynamic threshold obtained by the above step does not trigger an exception (the current data is normal), but the warning threshold prompts that “the future 1-minute temperature will reach 73℃ (close to the 80℃ protection value)”, the operator can adjust the test parameters (such as reducing the target current) in advance to avoid triggering the “temperature over 80℃ shutdown” of step 3.3 later, and reduce the probability of damage to the test sample due to over-limit;

[0112] If the warning prompt of this step is not intervened in time, and the subsequent real-time data exceeds the above dynamic threshold (such as the temperature reaching 82℃), the above step still triggers the shutdown protection immediately, forming a complete protection chain of “warning-intervention-shutdown”, which not only avoids “passive shutdown”, but also ensures the final safety.

[0113] In addition, the dynamic threshold supports the prediction calculation of the present step. For example, the prediction temperature of the present step corresponds to a temperature warning threshold (0.9 x Tprot), wherein Tprot is the protection threshold when the temperature exceeds the threshold in step S33, i.e., the warning threshold of step S53 is a "buffer extension" of the protection threshold of step S33. For example, the prediction resistance of step S53 corresponds to a resistance warning threshold (1.1 x Ravg), wherein the calculation basis of Ravg (average resistance in the previous 10 minutes) is "valid resistance data determined as normal by step S33" (excluding invalidly marked abnormal resistance data), which ensures the accuracy of Ravg and further ensures the rationality of the warning threshold of step S53.

[0114] Specifically, step S60 includes:

[0115] Step S61: The valid data set, compensated resistance data, abnormality determination result, abnormality log, correlation analysis result, prediction result, and user-set recording interval are stored in layers, and real-time high-frequency data is compressed into processing data stored by time interval, and the storage content includes test number, time stamp, temperature, voltage, current, resistance, abnormality mark, and prediction value; the data real-time and storage efficiency are balanced, the test data is traceable, and data loss caused by hardware failure is avoided.

[0116] Step S62: Real-time temperature data, temperature curve, real-time voltage data, voltage curve, real-time resistance data, and resistance curve are displayed, and real-time temperature data, real-time voltage data, and real-time resistance data are displayed according to user filtering instructions; for example, a real-time data window (channels 1-30 are arranged), a curve window (including a prediction trend line, and a dashed line mark), and specific values can be viewed by mouse hovering, and data changes are directly presented, so that an operator can quickly master the test state, risks are predicted through curve trends, and test monitoring efficiency is improved.

[0117] In particular, in step S70, a preset PDF template is called, and test basic information (number, test sample, and date), parameter settings (Iset, system protection temperature, etc.), data summary (valid data set, compensated resistance data, abnormality determination result, abnormality log, correlation analysis result, and prediction result), analysis result (abnormality log and correlation determination), and the filled report draft (including data table and curve atlas) are automatically filled. In this way, scattered data is integrated into a standardized report structure, and curve atlas is directly inserted to ensure completeness of the content, which can reduce the workload of manual report arrangement, ensure uniformity of the report format, and ensure accuracy of the data. At the same time, the test report includes analysis result ratings A, B, and C, A indicates that there is no abnormality, B indicates that there is a warning, C indicates that the machine is triggered to stop, and A indicates that the test sample is qualified.

[0118] Referring to Figure 4As shown, the embodiment of the present application further discloses a testing device of a direct current large current power supply, comprising:

[0119] The data acquisition unit 100 is used for acquiring multiple temperature information, multiple voltage information and multiple current information of the test sample, forming an original data set, wherein the original data set comprises multiple information items, each information item records a test sample number, a time stamp, a temperature corresponding to the time stamp, a current corresponding to the time stamp and a voltage corresponding to the time stamp, wherein the temperature corresponding to the time stamp is marked with a valid or invalid mark, the current corresponding to the time stamp is marked with a valid or invalid mark, and the voltage corresponding to the time stamp is marked with a valid or invalid mark;

[0120] The data preprocessing and compensation unit 200 is used for removing the data with invalid marks in the original data set, calling a two-item temperature compensation formula according to a preset temperature coefficient of the test sample material, calculating a compensation resistance corresponding to each time stamp, and obtaining a compensation resistance data set;

[0121] The dynamic abnormality judgment unit 300 is used for determining that the current test stage is in a current rising period, a current stable period or a current falling period according to multiple currents with valid marks and a target current set by a user, outputting a stage mark with one of the current rising period, the current stable period and the current falling period; based on the current test stage, calling a corresponding formula to calculate abnormality judgment thresholds of the current, the temperature and the voltage, and outputting a test normal instruction, a pre-warning instruction or a shutdown instruction according to an abnormality judgment result;

[0122] The correlation judgment unit 400 is used for judging correlation rationality of the temperature data and the resistance data of the test sample and stability of the resistance data, and obtaining a correlation analysis result;

[0123] The trend prediction unit 500 is used for predicting a predicted temperature and a predicted resistance of a future prediction time interval according to temperature data and compensation resistance data of multiple time stamps before a current time stamp, and outputting a prediction result;

[0124] The data storage and display unit 600 is used for storing and displaying the valid data set, the compensation resistance data, the abnormality judgment result, an abnormality log, the correlation analysis result, the prediction result and a user setting record interval;

[0125] The output unit 700 is used for outputting a test report containing the valid data set, the compensation resistance data set, the abnormality judgment result, the correlation analysis result and the prediction result, wherein the test report contains test analysis ratings A, B and C, the rating A indicates no abnormality, the rating B indicates a pre-warning, and the rating C indicates triggering of shutdown.

[0126] Further, the embodiment of the present application further discloses an electronic device, Figure 5Fig. 1 is a structural diagram of an electronic device 20 according to an exemplary embodiment, and the content of the figure should not be considered as any limitation on the scope of use of the present application.

[0127] Figure 5 Fig. 1 is a structural diagram of an electronic device 20 according to an exemplary embodiment, and the content of the figure should not be considered as any limitation on the scope of use of the present application.

[0128] In the present embodiment, the power supply 23 is configured to provide working voltage for each hardware device on the electronic device 20; the communication interface 24 is configured to create a data transmission channel between the electronic device 20 and external devices, and the communication protocol followed by the communication interface 24 can be any communication protocol applicable to the technical solution of the present application, which is not limited here; the input and output interface 25 is configured to obtain external input data or output data to the outside, and the specific interface type can be selected according to the specific application needs, which is not limited here.

[0129] In addition, the storage 22 as a carrier of resource storage can be a read-only memory, a random access memory, a magnetic disk or an optical disk, etc., and the resources stored thereon can include an operating system 221, a computer program 222, etc., and the storage mode can be temporary storage or permanent storage.

[0130] The operating system 221 is configured to manage and control each hardware device on the electronic device 20 and the computer program 222, and can be Windows Server, Netware, Unix, Linux, etc. In addition to the computer program capable of completing the power supply test method executed by the electronic device 20 disclosed in any of the foregoing embodiments, the computer program 222 can further include a computer program capable of completing other specific work.

[0131] The embodiments in the present specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts of each embodiment can be referred to each other. For the device disclosed in the embodiments, since it corresponds to the method disclosed in the embodiments, the description is relatively simple, and the relevant parts can be referred to the method part.

[0132] Those skilled in the art will further realize that the mere conception of the examples described herein is not inducing the patentable subject matter recited in each claim. The combinations of claim limitations noted herein are not restrictive unless specified as such. Thus, for any one of the examples described herein, each claim limitation can be combined with the other ones, even though not explicitly mentioned or not explicitly combined. One skilled in the art will readily recognize from the disclosure herein, for each of the examples, how to produce and use alternative embodiments. The instant disclosure includes all such alternatives.

[0133] The steps of a method or algorithm described in connection with the examples disclosed herein can be embodied directly in hardware, in a software module executed by a processor, or in a combination of the two. A software module can reside in RAM, flash memory, ROM, electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), registers, hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art. An exemplary storage medium is coupled to the processor such that the processor can read information from, and write information to, the storage medium. In the alternative, the storage medium can be integral to the processor. The processor and the storage medium can reside in an ASIC.

[0134] Finally, it should be noted that the terms "comprises", "comprising", or other variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but can include other elements not expressly listed or inherent to such process, method, article, or apparatus. An element proceeded by "comprises... a" does not, without more constraints, preclude the existence of additional identical elements in the process, method, article, or apparatus that comprises the element.

Claims

1. A method for testing a direct current high current power supply, comprising: obtaining a plurality of temperature information, a plurality of voltage information and a plurality of current information of a test sample to form an original data set, the original data set comprising a plurality of information items, each information item recording a test sample number, a time stamp, a temperature corresponding to the time stamp, a current corresponding to the time stamp and a voltage corresponding to the time stamp, wherein the temperature corresponding to the time stamp is marked with a valid or invalid mark, the current corresponding to the time stamp is marked with a valid or invalid mark, and the voltage corresponding to the time stamp is marked with a valid or invalid mark; removing the data with invalid marks in the original data set, calling a two-item temperature compensation formula according to a preset temperature coefficient of the test sample material, calculating a compensation resistance corresponding to each time stamp, and obtaining a compensation resistance data set; determining that the current test stage is in a current rising period, a current stable period or a current falling period according to a plurality of currents with valid marks and a user-set target current, and outputting a stage mark with one of the current rising period, the current stable period and the current falling period; calling a corresponding formula to calculate abnormality determination thresholds of the current, the temperature and the voltage based on the current test stage, and outputting a test normal instruction, a pre-warning instruction or a shutdown instruction according to an abnormality determination result; judging the correlation rationality of the temperature data and the resistance data of the test sample and the stability of the resistance data to obtain a correlation analysis result; predicting a predicted temperature and a predicted resistance of a future prediction time interval according to the temperature data of a plurality of time stamps before the current time stamp and the compensation resistance data, and outputting a prediction result; storing and displaying the valid data set, the compensation resistance data, the abnormality determination result, the abnormality log, the correlation analysis result, the prediction result and a user-set record interval; outputting a test report containing the valid data set, the compensation resistance data set, the abnormality determination result, the correlation analysis result and the prediction result, the test report containing test analysis ratings A, B and C, the A rating indicating no abnormality, the B rating indicating a pre-warning, and the C rating indicating triggering a shutdown.

2. The test method according to claim 1, wherein a plurality of temperature information, a plurality of voltage information and a plurality of current information of the test sample are acquired to form a raw data set, the raw data set including a plurality of information pieces, each information piece recording a test sample number, a time stamp, a temperature corresponding to the time stamp, a current corresponding to the time stamp and a voltage corresponding to the time stamp, wherein, The temperature corresponding to the time stamp is marked with a valid or invalid mark, the current corresponding to the time stamp is marked with a valid or invalid mark, and the voltage corresponding to the time stamp is marked with a valid or invalid mark, comprising: obtaining real-time temperatures, real-time voltages and output real-time currents of a plurality of channels of a test sample to obtain an original data set after processing, the original data set comprising a plurality of information items, each information item recording a test sample number, a time stamp, a temperature corresponding to the time stamp, a current corresponding to the time stamp and a voltage corresponding to the time stamp; determining whether the data in each channel in the obtained original data set is continuous according to a parameter range: if no data or data exceeding the parameter range is detected for 3 seconds continuously, the original data set of the channel is assigned an invalid mark, and a channel failure log is outputted; if no data or data exceeding the parameter range is not detected for 3 seconds continuously, the original data set of the channel is assigned a valid mark.

3. The test method of claim 1, wherein the invalidly marked data in the original data set is removed, a two-item temperature compensation formula is called according to a preset temperature coefficient of the test material, a compensated resistance corresponding to each timestamp is calculated, and a compensated resistance data set is obtained; comprising: removing the original data set with invalidly marked channels, and performing smoothing processing on the original data set with validly marked channels to obtain a valid data set; obtaining original resistances of multiple channels in the valid data set and corresponding real-time temperatures, and determining compensated resistances corresponding to the original resistances of the multiple channels according to a first temperature coefficient and a second temperature coefficient of the test material, wherein the first temperature coefficient is a temperature coefficient of the material at 20 DEG C, reflecting a linear influence of a reaction temperature on the material resistance, and the second temperature coefficient is a nonlinear influence of the temperature at 20 DEG C on the material.

4. The test method of claim 1, wherein a current test phase is determined to be in a current-increasing period, a current-constant period or a current-decreasing period according to multiple currents with valid marks and a user-set target current, and a phase mark with one of the current-increasing period, the current-constant period and the current-decreasing period is output; based on the current test phase, a corresponding formula is called to calculate abnormality determination thresholds of the current, the temperature and the voltage, and a test normal instruction, a pre-warning instruction or a shutdown instruction is output according to an abnormality determination result; comprising: determining the current test phase to be in the current-increasing period, the current-constant period or the current-decreasing period according to the multiple currents with valid marks and the user-set target current, and outputting the phase mark with one of the current-increasing period, the current-constant period and the current-decreasing period; based on the current test phase, calling a corresponding threshold formula to calculate abnormality determination thresholds of the current, the temperature and the voltage, and generating a dynamic threshold set containing current thresholds, temperature thresholds and voltage thresholds; based on the dynamic thresholds in the dynamic threshold set, determining whether there is abnormal data in the valid data set, the compensated resistance data and a system protection temperature, and outputting the abnormality determination result and an abnormality log, wherein the abnormality determination result includes the test normal instruction, the abnormal pre-warning instruction or the shutdown instruction, and the abnormality log contains timestamp and abnormality type information, the test normal instruction is used to control the test process to continue, the abnormal pre-warning instruction is used to generate abnormal pre-warning information, and the shutdown instruction is used to control the test hardware to decrease current and shut down.

5. The test method of claim 4, wherein based on the current test phase, a corresponding threshold formula is called to calculate abnormality determination thresholds of the current, the temperature and the voltage, and a dynamic threshold set containing current thresholds, temperature thresholds and voltage thresholds is generated; specifically comprising: If the current test phase is in the upflow period or the downflow period, the dynamic current threshold is determined according to The dynamic temperature threshold is 5℃; wherein, It is the real-time current, I(t−1) is the real-time current of the previous 1s, Iset is the user set target current; If the current test phase is in the steady flow period, the dynamic current threshold is determined according to the dynamic temperature threshold is 2°C. the dynamic voltage threshold is determined according to ΔUth=Uavgx0.05, wherein Uavg is an average value of voltage data of a single channel.

6. The test method of claim 5, determining whether there is abnormal data in the effective data set, the compensation resistance data and the system protection temperature based on a dynamic threshold in the dynamic threshold set, outputting an abnormal determination result and an abnormal log, the abnormal determination result including a normal test instruction, an abnormal early warning instruction or a shutdown instruction, the abnormal log containing a timestamp and abnormal type information, the normal test instruction being used to control the test process to continue, the abnormal early warning instruction being used to generate abnormal early warning information, and the shutdown instruction being used to control the test hardware to reduce the flow and shut down; comprising: If the real-time current is detected to meet for 3 seconds, an abnormal early warning instruction is output; if the real-time current is not restored within 10 seconds, a shutdown instruction is output. If the real-time temperature is detected to satisfy a shutdown instruction is outputted, wherein T(t-1) is the real-time temperature of the previous 1s, and Tprot (80℃) is the system protection temperature. If the real-time voltage is detected to meet the condition for 3 s continuously an abnormal early warning instruction is output; if the real-time voltage is not recovered within 10 s, a shutdown instruction is output.

7. The test method of claim 1, predicting a predicted temperature and a predicted resistance in a future prediction time interval according to temperature data and compensation resistance data of a plurality of timestamps before the current timestamp, and outputting a prediction result; comprising: determining a temperature coefficient deviation rate according to the supplementary resistance data, the corresponding temperature data and the material standard temperature coefficient of the sample, and determining the rationality of the relationship between the temperature and the resistance according to the temperature coefficient deviation rate; determining a coefficient of variation according to the voltage data of the effective data set and the current data in the constant current period, and determining the resistance stability of the sample according to the coefficient of variation.

8. The test method of claim 1, predicting a predicted temperature and a predicted resistance in a future prediction time interval according to temperature data and compensation resistance data of a plurality of timestamps before the current timestamp, and outputting a prediction result; comprising: performing weighted processing on the temperature data and the resistance data corresponding to the plurality of timestamps before the current timestamp; obtaining the predicted temperature in the future prediction time interval according to the temperature weight data set, and obtaining the predicted resistance in the future prediction time interval according to the resistance weight data set; comparing the predicted temperature with a future temperature early warning threshold and comparing the predicted resistance with a future resistance early warning threshold to determine whether to output an early risk prompt.

9. A test device for a direct current large current power supply, comprising: a data acquisition unit configured to acquire a plurality of temperature information, a plurality of voltage information and a plurality of current information of a sample, and form an original data set, the original data set comprising a plurality of information items, each information item recording a sample number, a timestamp, a temperature corresponding to the timestamp, a current corresponding to the timestamp and a voltage corresponding to the timestamp, wherein the temperature corresponding to the timestamp is marked with an effective or ineffective mark, the current corresponding to the timestamp is marked with an effective or ineffective mark, and the voltage corresponding to the timestamp is marked with an effective or ineffective mark; a data preprocessing and compensation unit configured to remove the data with the ineffective mark in the original data set, and calculate the compensation resistance corresponding to each timestamp according to a preset temperature coefficient of the sample material by calling a two-item temperature compensation formula, to obtain a supplementary resistance data set; a dynamic abnormality determination unit configured to determine that the current test stage is in a rising current period, a constant current period or a falling current period according to a plurality of currents with the effective mark and a user-set target current, and output a stage mark with one of the rising current period, the constant current period and the falling current period; based on the current test stage, calculate abnormal determination thresholds of the current, the temperature and the voltage by calling corresponding formulas, and output a test normal instruction, an early warning instruction or a shutdown instruction according to the abnormal determination result. The correlation judgment unit is configured to judge the correlation rationality between the temperature data and the resistance data of the test sample and the stability of the resistance data, and obtain a correlation analysis result; The trend prediction unit is configured to predict a predicted temperature and a predicted resistance in a future prediction time interval according to the temperature data and the compensated resistance data of a plurality of time stamps before a current time stamp, and output a prediction result; The data storage and display unit is configured to store and display the effective data set, the compensated resistance data, the abnormality judgment result, the abnormality log, the correlation analysis result, the prediction result and the user setting record interval; The output unit is configured to output a test report containing the effective data set, the compensated resistance data set, the abnormality judgment result, the correlation analysis result and the prediction result, and the test report contains test analysis ratings A, B and C, the A rating indicates no abnormality, the B rating indicates a warning, and the C rating indicates triggering a shutdown.

10. A testing apparatus for a direct current high current power supply, comprising a processor and a memory; wherein, The memory is configured to store a computer program, and the computer program is loaded and executed by the processor to implement the test method according to any one of claims 1-8.

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