CN117388732B - High-power density direct-current power supply safety monitoring method and system - Google Patents

Abstract

The invention provides a high-power density direct-current power supply safety monitoring method and system, and relates to the technical field of electricity. The method comprises the following steps: collecting charging current data of a direct current power supply; acquiring performance parameters of the rechargeable battery; collecting temperature information of a rechargeable battery; determining theoretical current data according to the performance parameters, the temperature information and the voltage data; determining a current stability score according to the charging current data and the theoretical current data; determining a stability score of the rechargeable battery according to the charging current data and the temperature information; determining a charging safety score according to the current stability score and the rechargeable battery stability score; and determining the time interval of the detection period according to the charge safety score. According to the invention, when the current is unstable, whether the current is caused by a battery or caused by a direct current power supply can be distinguished, so that the factors of the current instability can be conveniently eliminated, and the charging safety is improved.

Description

High-power density direct-current power supply safety monitoring method and system

Technical Field

The invention relates to the technical field of electricity, in particular to a high-power-density direct-current power supply safety monitoring method and system.

Background

High power density dc power sources include regulated dc power sources that may be used to charge batteries, for example, batteries of electric vehicles. In the related art, during the charging process, the charging safety may be adversely affected by the unstable current, so that the charging current may be monitored, thereby improving the charging safety. However, the instability of the charging current may be caused by various reasons, for example, due to a battery failure or due to the instability of the current of the dc power supply itself, and it is difficult to distinguish the factor of the instability of the current in the related art, and thus it is also difficult to exclude the factor of the instability of the current.

The information disclosed in the background section of the application is only for enhancement of understanding of the general background of the application and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.

Disclosure of Invention

The embodiment of the invention provides a high-power density direct current power supply safety monitoring method and a system, which can distinguish whether the current instability is caused by a battery or a direct current power supply, so that the factors of the current instability can be conveniently eliminated, and the charging safety is improved.

According to a first aspect of an embodiment of the present invention, there is provided a high power density dc power supply safety monitoring method, including:

Collecting charging current data of a direct current power supply at a plurality of moments in a current detection period;

acquiring performance parameters of a rechargeable battery connected with the direct current power supply, wherein the performance parameters comprise impedance of the rechargeable battery;

collecting temperature information of the rechargeable battery at a plurality of moments in the current detection period;

Determining theoretical current data of the rechargeable battery at a plurality of moments in a current detection period according to the performance parameters of the rechargeable battery, the temperature information of the rechargeable battery and the voltage data of the direct current power supply;

determining a current stability score of the direct current power supply according to the charging current data and the theoretical current data;

Determining a stability score of the rechargeable battery according to the charging current data and the temperature information of the rechargeable battery;

Determining a charging safety score of a direct current power supply according to the current stability score and the rechargeable battery stability score;

and determining the time interval between the ending time of the current detection period and the starting time of the next detection period according to the charging safety score.

According to one embodiment of the present invention, determining theoretical current data of the rechargeable battery at a plurality of moments in a current detection period according to performance parameters of the rechargeable battery, temperature information of the rechargeable battery and voltage data of the direct current power supply includes:

Selecting a plurality of sample batteries in a sample library according to the performance parameters of the rechargeable batteries, wherein the sample batteries have the same specification as the rechargeable batteries;

determining an average impedance decay function of the plurality of sample cells according to historical temperature data and historical current data at a plurality of historical moments during charging of the plurality of sample cells;

Determining theoretical impedance of the rechargeable battery at a plurality of moments in a current detection period according to the average impedance decay function and temperature information of the rechargeable battery;

and determining theoretical current data of the rechargeable battery at a plurality of moments in the current detection period according to the voltage data of the direct current power supply and the theoretical impedance.

According to one embodiment of the present invention, determining an average impedance decay function for a plurality of sample cells from historical temperature data and historical current data for a plurality of historical moments during charging of the plurality of sample cells includes:

Acquiring historical temperature data and historical current data of a plurality of historical moments during charging of a plurality of sample batteries;

determining a charging voltage during which the plurality of sample cells are charged;

Determining real-time impedance of the plurality of sample batteries at a plurality of historical moments according to the charging voltage and the historical current data;

Determining an impedance decay function of each sample cell according to the historical temperature data and the real-time impedance, wherein the impedance decay function is used for describing the relation between the impedance and the temperature of the sample cell;

an average impedance decay function of the plurality of sample cells is determined based on the impedance decay functions of the respective sample cells.

According to one embodiment of the present invention, determining a current stability score of the dc power source itself from the charging current data and the theoretical current data includes:

Acquiring current deviation data between charging current data and theoretical current data at a plurality of moments in the current detection period;

Determining a current deviation average value, a current deviation standard deviation and a current deviation maximum value according to the current deviation data;

Fitting the charging current data at a plurality of moments in the current detection period to obtain a charging current function curve;

fitting theoretical current data at a plurality of moments in the current detection period to obtain a theoretical current function curve;

and determining the current stability score according to the current deviation average value, the current deviation standard deviation, the current deviation maximum value, the charging current function curve and the theoretical current function curve.

According to one embodiment of the invention, determining the current stability score from the current deviation average, the current deviation standard deviation, the current deviation maximum, the charging current function curve and the theoretical current function curve comprises:

According to the formula

The current stability score is obtained S _I, wherein,For the current deviation average value, Δi _max is the current deviation maximum value, D (Δi) is the current deviation standard deviation, t _s is the start time of the current detection period, t _f is the end time of the current detection period, I _c (t) is the charging current function curve, I _t (t) is the theoretical current function curve, n is the number of times, n is a positive integer, α _I is a preset current stability coefficient, and count is a count function.

According to one embodiment of the present invention, determining a rechargeable battery stability score from the charging current data and the temperature information of the rechargeable battery includes:

According to the formula

Determining a stability score S _C of the rechargeable battery, wherein I _j is charging current data of the jth moment in the current detection period, beta ₁ is a first preset multiple, beta ₂ is a second preset multiple, I _R is rated current, T _j is temperature information of the rechargeable battery of the jth moment in the current detection period, beta ₃ is a third preset multiple, T _m is preset safe temperature, n is the number of a plurality of moments, j is less than or equal to n, j and n are positive integers, and count is a counting function.

According to one embodiment of the invention, determining a time interval between an end time of the current detection period and a start time of a next detection period according to the charge safety score comprises:

According to the formula

And determining a time interval delta t between the ending time of the current detection period and the starting time of the next detection period, wherein delta t _p is a preset time interval, S _s is the charge safety score, and S _T is a preset scoring threshold.

According to a second aspect of embodiments of the present invention, there is provided a high power density dc power supply safety monitoring system comprising:

The charging current data module is used for collecting charging current data of the direct-current power supply at a plurality of moments in the current detection period;

The performance parameter module is used for acquiring the performance parameter of the rechargeable battery connected with the direct-current power supply, wherein the performance parameter comprises the impedance of the rechargeable battery;

The temperature information module is used for collecting temperature information of the rechargeable battery at a plurality of moments in the current detection period;

the theoretical current data module is used for determining theoretical current data of the rechargeable battery at a plurality of moments in a current detection period according to the performance parameters of the rechargeable battery, the temperature information of the rechargeable battery and the voltage data of the direct current power supply;

the current stability scoring module is used for determining the current stability score of the direct current power supply according to the charging current data and the theoretical current data;

The rechargeable battery stability scoring module is used for determining the stability score of the rechargeable battery according to the charging current data and the temperature information of the rechargeable battery;

The charging safety scoring module is used for determining the charging safety score of the direct-current power supply according to the current stability score and the rechargeable battery stability score;

And the time interval module is used for determining the time interval between the ending time of the current detection period and the starting time of the next detection period according to the charging safety score.

According to one embodiment of the invention, the theoretical current data module is further configured to:

Selecting a plurality of sample batteries in a sample library according to the performance parameters of the rechargeable batteries, wherein the sample batteries have the same specification as the rechargeable batteries;

determining an average impedance decay function of the plurality of sample cells according to historical temperature data and historical current data at a plurality of historical moments during charging of the plurality of sample cells;

Determining theoretical impedance of the rechargeable battery at a plurality of moments in a current detection period according to the average impedance decay function and temperature information of the rechargeable battery;

and determining theoretical current data of the rechargeable battery at a plurality of moments in the current detection period according to the voltage data of the direct current power supply and the theoretical impedance.

According to one embodiment of the invention, the theoretical current data module is further configured to:

Acquiring historical temperature data and historical current data of a plurality of historical moments during charging of a plurality of sample batteries;

determining a charging voltage during which the plurality of sample cells are charged;

Determining real-time impedance of the plurality of sample batteries at a plurality of historical moments according to the charging voltage and the historical current data;

Determining an impedance decay function of each sample cell according to the historical temperature data and the real-time impedance, wherein the impedance decay function is used for describing the relation between the impedance and the temperature of the sample cell;

an average impedance decay function of the plurality of sample cells is determined based on the impedance decay functions of the respective sample cells.

According to one embodiment of the invention, the current stability scoring module is further configured to:

Acquiring current deviation data between charging current data and theoretical current data at a plurality of moments in the current detection period;

Determining a current deviation average value, a current deviation standard deviation and a current deviation maximum value according to the current deviation data;

Fitting the charging current data at a plurality of moments in the current detection period to obtain a charging current function curve;

fitting theoretical current data at a plurality of moments in the current detection period to obtain a theoretical current function curve;

and determining the current stability score according to the current deviation average value, the current deviation standard deviation, the current deviation maximum value, the charging current function curve and the theoretical current function curve.

According to one embodiment of the invention, the current stability scoring module is further configured to:

According to the formula

The current stability score is obtained S _I, wherein,For the current deviation average value, Δi _max is the current deviation maximum value, D (Δi) is the current deviation standard deviation, t _s is the start time of the current detection period, t _f is the end time of the current detection period, I _c (t) is the charging current function curve, I _t (t) is the theoretical current function curve, n is the number of times, n is a positive integer, α _I is a preset current stability coefficient, and count is a count function.

According to one embodiment of the present invention, the rechargeable battery stability scoring module is further configured to:

According to the formula

Determining a stability score S _C of the rechargeable battery, wherein I _j is charging current data of the jth moment in the current detection period, beta ₁ is a first preset multiple, beta ₂ is a second preset multiple, I _R is rated current, T _j is temperature information of the rechargeable battery of the jth moment in the current detection period, beta ₃ is a third preset multiple, T _m is preset safe temperature, n is the number of a plurality of moments, j is less than or equal to n, j and n are positive integers, and count is a counting function.

According to one embodiment of the invention, the time interval module is further configured to:

According to the formula

And determining a time interval delta t between the ending time of the current detection period and the starting time of the next detection period, wherein delta t _p is a preset time interval, S _s is the charge safety score, and S _T is a preset scoring threshold.

According to a third aspect of embodiments of the present invention, there is provided a high power density dc power supply safety monitoring device comprising: a processor; a memory for storing processor-executable instructions; wherein the processor is configured to invoke the instructions stored by the memory to perform the high power density dc power supply safety monitoring method.

According to a fourth aspect of embodiments of the present invention, there is provided a computer readable storage medium having stored thereon computer program instructions which, when executed by a processor, implement the high power density dc power supply safety monitoring method.

According to the high-power density direct current power supply safety monitoring method provided by the embodiment of the invention, actually collected charging current data at a plurality of moments can be obtained, theoretical current data is determined according to the temperature information of the battery, the influence of the battery is eliminated based on the theoretical current data, the current stability score of the direct current power supply is determined, and the stability score of the charging battery is also determined, so that when the current is unstable, whether the current is caused by the battery or caused by the direct current power supply can be distinguished, the factors of the current instability can be eliminated conveniently, and the charging safety is improved. When the theoretical current data is determined, the theoretical impedance of the rechargeable battery at each temperature can be obtained through the historical data of a plurality of sample batteries with the same specification as the rechargeable battery, so that the theoretical current data of the rechargeable battery at a plurality of moments can be determined, a data basis is provided for eliminating current change factors caused by the rechargeable battery of the battery, and the accuracy of judging the current stability of the direct current power supply can be improved. When the current stability score of the direct current power supply is determined, the influence of current fluctuation caused by a battery can be eliminated based on theoretical current data, so that the current stability of the direct current power supply can be determined based on the difference between charging current data and theoretical current data, the current stability of the direct current power supply can be comprehensively judged based on discrete current deviation data, a continuous charging current function curve and a theoretical current function curve, the current stability score can be solved based on two angles of the discrete data and the continuous data, and the accuracy and objectivity of the current stability score are improved. And the stability of the rechargeable battery can be further determined by counting the abnormal times of the current and the abnormal times of the temperature, so that the accuracy and objectivity of the stability scoring of the rechargeable battery are improved. Further, the time interval between detection periods can be determined based on the charging safety score, the time interval is increased when the charging safety is high, the occupation of processing resources is reduced, the time interval is reduced when the charging safety is low, fault factors are found in time, and the charging safety is improved.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention as claimed. Other features and aspects of the present invention will become apparent from the following detailed description of exemplary embodiments, which proceeds with reference to the accompanying drawings.

Drawings

In order to more clearly illustrate the embodiments of the invention or the solutions of the prior art, the drawings which are necessary for the description of the embodiments or the prior art will be briefly described below, it being obvious that the drawings in the following description are only some embodiments of the invention, and that other embodiments may be obtained from these drawings without inventive effort to a person skilled in the art,

FIG. 1 schematically illustrates a flow chart of a high power density DC power source safety monitoring method according to an embodiment of the invention;

Fig. 2 schematically illustrates a block diagram of a high power density dc power supply safety monitoring system according to an embodiment of the invention.

Detailed Description

For the purpose of making the objects, technical solutions and advantages of the embodiments of the present invention more apparent, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is apparent that the described embodiments are only some embodiments of the present invention, not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

The technical scheme of the invention is described in detail below by specific examples. The following embodiments may be combined with each other, and some embodiments may not be repeated for the same or similar concepts or processes.

Fig. 1 schematically illustrates a flow chart of a high power density dc power supply safety monitoring method according to an embodiment of the present invention, as shown in fig. 1, the method includes:

Step S101, collecting charging current data of a direct current power supply at a plurality of moments in a current detection period;

Step S102, obtaining performance parameters of a rechargeable battery connected with the direct current power supply, wherein the performance parameters comprise impedance of the rechargeable battery;

step S103, collecting temperature information of the rechargeable battery at a plurality of moments in the current detection period;

step S104, determining theoretical current data of the rechargeable battery at a plurality of moments in a current detection period according to the performance parameters of the rechargeable battery, the temperature information of the rechargeable battery and the voltage data of the direct current power supply;

Step S105, determining a current stability score of the direct current power supply according to the charging current data and the theoretical current data;

step S106, determining a stability score of the rechargeable battery according to the charging current data and the temperature information of the rechargeable battery;

step S107, determining a charging safety score of the direct current power supply according to the current stability score and the rechargeable battery stability score;

Step S108, determining a time interval between the end time of the current detection period and the start time of the next detection period according to the charge safety score.

According to the high-power density direct current power supply safety monitoring method provided by the embodiment of the invention, actually collected charging current data at a plurality of moments can be obtained, theoretical current data is determined according to the temperature information of the battery, the influence of the battery is eliminated based on the theoretical current data, the current stability score of the direct current power supply is determined, and the stability score of the charging battery is also determined, so that when the current is unstable, whether the current is caused by the battery or caused by the direct current power supply can be distinguished, the factors of the current instability can be eliminated conveniently, and the charging safety is improved. Further, the time interval between detection periods can be determined based on the charging safety score, the time interval is increased when the charging safety is high, the occupation of processing resources is reduced, the time interval is reduced when the charging safety is low, fault factors are found in time, and the charging safety is improved.

According to an embodiment of the present invention, in step S101, each detection period may include a plurality of time instants, for example, the duration of each detection period is 10 seconds, and each second may be taken as one time instant, and then 10 time instants may be included in the detection period, which is not limited by the present invention. In the detection period, charging current data at each time may be acquired, for example, the charging current data at each time is acquired by a current sensor, and the charging current data is actually acquired current data.

According to one embodiment of the present invention, in step S102, if the dc power supply is charging the rechargeable battery, the dc power supply may be communicatively connected to the controller of the charging current to obtain the performance parameter of the rechargeable battery. In an example, the performance parameter includes an impedance of the rechargeable battery, the impedance being a design impedance of the rechargeable battery, an actual impedance of the rechargeable battery during the charging process may be equal to the design impedance, or may deviate from the design impedance as the charging process proceeds, for example, a temperature of the rechargeable battery increases and the actual impedance decreases as the charging process proceeds such that the actual impedance is smaller than the design impedance. The present invention does not limit the relationship between the actual impedance and the design impedance.

According to one embodiment of the present invention, in step S103, temperature information of the battery may be collected at a plurality of times of the current detection period, for example, temperature information of the rechargeable battery at a plurality of times may be collected by a temperature sensor, the temperature information being actually collected temperature data.

According to an embodiment of the present invention, if an unstable current occurs, it may have an adverse effect on the charging safety of the rechargeable battery, however, both the rechargeable battery and the dc power supply may have an unstable current, for example, the rechargeable battery may have an excessively high temperature, thereby causing a decrease in impedance, resulting in an increase or even abrupt change in charging current, and the dc power supply may have an unstable current, for example, malfunction, aging, etc. of internal electronic devices. Therefore, it is often difficult to distinguish the cause of the current instability, i.e., whether the current instability is caused by the rechargeable battery or by the direct current power supply itself. Therefore, in order to solve the technical problem, the invention can eliminate the influence of the rechargeable battery to determine the current stability score of the direct current power supply, thereby determining whether the current instability condition is caused by the direct current power supply. In an example, theoretical current data of the rechargeable battery at each moment of the current detection period may be determined, where the theoretical current data is current data calculated based on actual temperature information of the rechargeable battery, that is, theoretical current data of the rechargeable battery at each temperature. And whether the current of the charging power supply itself is stable or not can be determined based on the deviation between the actual charging current data and the theoretical current data. For example, if the current is unstable due to a battery failure, the theoretical current data may change, for example, a sudden change may occur, and if the actual change of the charging current data is inconsistent with the change of the theoretical current data (for example, the change amplitude of the actual charging current data is higher than the change amplitude of the theoretical current data), the inconsistent portion of the two changes may be considered to be caused by the dc power supply itself, so that the deviation of the actual charging current data and the theoretical current data may be determined, and whether the dc power supply itself is unstable or not may be determined based on the deviation, or the influence of the current change caused by the charging battery may be excluded based on the theoretical current data.

According to one embodiment of the present invention, theoretical current data of the rechargeable battery at a plurality of times within the present detection period may be determined in step S104. For example, the charging currents of a plurality of sample batteries with good quality and no faults at various temperatures can be counted to obtain theoretical current data, and the sample batteries have the same specification as the rechargeable batteries, so that the theoretical current data of the similar batteries can be determined.

According to one embodiment of the present invention, step S104 includes: selecting a plurality of sample batteries in a sample library according to the performance parameters of the rechargeable batteries, wherein the sample batteries have the same specification as the rechargeable batteries; determining an average impedance decay function of the plurality of sample cells according to historical temperature data and historical current data at a plurality of historical moments during charging of the plurality of sample cells; determining theoretical impedance of the rechargeable battery at a plurality of moments in a current detection period according to the average impedance decay function and temperature information of the rechargeable battery; and determining theoretical current data of the rechargeable battery at a plurality of moments in the current detection period according to the voltage data of the direct current power supply and the theoretical impedance.

According to one embodiment of the invention, an average impedance decay function of the plurality of sample cells may be determined, and the average impedance decay function may be used to represent an average change law of the impedance of the plurality of sample cells at a plurality of temperatures. In order to obtain the change rule, and to improve the accuracy of data and the consistency of specifications, a plurality of sample batteries can be selected in a sample library based on the performance parameters of the rechargeable battery, and the selected sample batteries can be consistent with the specifications of the rechargeable battery, so that the rule obtained based on the sample batteries is also applicable to the rechargeable battery.

According to one embodiment of the present invention, the sample library may further have recorded therein historical temperature data and historical current data of a plurality of sample cells at a plurality of historical moments. For example, historical temperature data and historical current data of the sample cells may be recorded as the sample cells are charged over time. So that the above-described change rule can be obtained based on the historical temperature data and the historical current data.

According to one embodiment of the present invention, determining an average impedance decay function for a plurality of sample cells from historical temperature data and historical current data for a plurality of historical moments during charging of the plurality of sample cells includes: acquiring historical temperature data and historical current data of a plurality of historical moments during charging of a plurality of sample batteries; determining a charging voltage during which the plurality of sample cells are charged; determining real-time impedance of the plurality of sample batteries at a plurality of historical moments according to the charging voltage and the historical current data; determining an impedance decay function of each sample cell according to the historical temperature data and the real-time impedance, wherein the impedance decay function is used for describing the relation between the impedance and the temperature of the sample cell; an average impedance decay function of the plurality of sample cells is determined based on the impedance decay functions of the respective sample cells.

According to one embodiment of the present invention, historical temperature data and historical current data may be obtained at a plurality of historical moments during charging of a plurality of sample batteries. In an example, for the sample battery 1, its historical temperature data and historical current data may be acquired at a plurality of historical moments, for example, its historical temperature data and historical current data may be acquired at a plurality of moments, respectively, during the process of charging the sample battery 1. Similarly, the historical temperature data and the historical current data may be collected separately at multiple times for the sample battery 2. The above process may be repeated to obtain historical temperature data and historical current data during charging of the plurality of sample batteries.

According to an embodiment of the present invention, a charging voltage of each sample battery during the above charging process may be obtained, and in an example, the charging voltage may be consistent with a voltage of the dc power supply, so as to improve accuracy of an average impedance decay function. Of course, the average change rule of the impedance of the plurality of sample batteries at various temperatures can be solved only if the average change rule is inconsistent with the voltage of the direct current power supply. The invention does not limit the specific value of the charging voltage.

According to one embodiment of the invention, the real-time impedance of each sample cell at a plurality of historic times may be determined based on the charging voltage and the historic current data. For example, the ratio of the charge voltage of each sample battery to the historical current data at each time instant may be used as the real-time impedance of the sample battery at each historical time instant.

According to one embodiment of the invention, the historical temperature data and the real-time impedance of each sample cell can be fitted, for example, each historical moment can correspond to one historical temperature data and the real-time impedance for each sample cell, therefore, a plurality of historical moments correspond to a plurality of historical temperature data and the real-time impedance, the historical temperature data and the real-time impedance of each sample cell can be fitted, and an impedance attenuation function of each sample cell can be obtained, and the impedance attenuation function of each sample cell is used for describing the relation between the impedance and the temperature of the sample cell.

According to one embodiment of the present invention, an average value of the impedance attenuation functions of each sample cell may be solved, for example, the impedance attenuation function of each sample cell corresponds to an impedance value at each temperature, the impedance values of the impedance attenuation functions of each sample cell at each temperature may be averaged to obtain an average impedance value, and a function formed by connecting the average impedance values is the average impedance attenuation function. The above steps are applicable to the scenario that the historical temperature data of the plurality of sample batteries are different, if the historical temperature data of the plurality of sample batteries are equal, for example, the real-time impedance of each sample battery is measured under the same historical temperature data, the real-time impedance of each sample battery under each historical temperature data can be averaged, and the average value of the impedance is used for fitting with the historical temperature data, so as to obtain the average impedance attenuation function. Of course, if the historical temperature data of the plurality of sample cells are equal, the step of obtaining the impedance decay function of each sample cell and then obtaining the average impedance decay function may be used, which is not limited in the present invention.

According to one embodiment of the present invention, the average impedance decay function may represent an average impedance of a plurality of batteries of the same size as a rechargeable battery at different temperatures, and the average impedance may be used as a theoretical impedance of the rechargeable battery at different temperatures. Since the temperature information of the rechargeable battery at each time has been measured in the current detection period, the temperature information of the rechargeable battery at each time may be substituted into the average impedance decay function, and the theoretical impedance of the rechargeable battery at each time may be obtained.

According to one embodiment of the present invention, since the voltage of the dc power supply is generally stable, the ratio between the voltage data of the dc power supply and the theoretical impedance at each time may be used as the theoretical current data at a plurality of times in the present detection period. The theoretical current data may represent theoretical current data of the rechargeable battery under external conditions of temperature and charging voltage at various times, and the current data may be different from actual charging current data, and as described above, the difference may be used to represent whether the current of the dc power supply itself is stable after excluding the current variation factor caused by the rechargeable battery.

By the method, the theoretical impedance of the rechargeable battery at each temperature can be obtained through the historical data of a plurality of sample batteries with the same specification as the rechargeable battery, so that the theoretical current data of the rechargeable battery at a plurality of moments can be determined, a data basis is provided for eliminating current change factors caused by the rechargeable battery of the rechargeable battery, and the accuracy of judging the current stability of the direct-current power supply can be improved.

According to an embodiment of the present invention, in step S105, the current variation factor of the rechargeable battery itself may be excluded according to the theoretical current data obtained above, the deviation between the charging current data and the theoretical current data may be determined, and the current stability of the dc power supply itself may be determined based on the deviation. For example, it may be determined whether the deviation is stable or whether the deviation is small, e.g., less than a certain set threshold, etc. Alternatively, the power circuit stability score may be determined in the following manner to determine the current stability of the dc power supply itself.

According to one embodiment of the present invention, step S105 may include: acquiring current deviation data between charging current data and theoretical current data at a plurality of moments in the current detection period; determining a current deviation average value, a current deviation standard deviation and a current deviation maximum value according to the current deviation data; fitting the charging current data at a plurality of moments in the current detection period to obtain a charging current function curve; fitting theoretical current data at a plurality of moments in the current detection period to obtain a theoretical current function curve; and determining the current stability score according to the current deviation average value, the current deviation standard deviation, the current deviation maximum value, the charging current function curve and the theoretical current function curve.

According to one embodiment of the present invention, current deviation data between charging current data and theoretical current data at a plurality of times in a current period may be calculated, for example, the charging current data at each time may be subtracted from the theoretical current data to obtain current deviation data, and the current deviation data corresponds to each time one by one.

According to one embodiment of the present invention, a statistical operation may be performed on current deviation data at a plurality of times, and a current deviation average value, a current deviation standard deviation, and a current deviation maximum value may be obtained, wherein the current deviation maximum value may be a maximum value of an absolute value of the current deviation data.

According to one embodiment of the present invention, the above plurality of pieces of statistical data may determine whether the current deviation data is stable from a statistical point of view, but the above data may determine whether the current deviation data is stable based only on discrete current deviation data at each time. Continuous data of the charging current data and the theoretical current data may also be acquired, so that whether the deviation of the current is stable or not is determined based on the continuous data.

According to one embodiment of the invention, the charging current data at a plurality of moments can be fitted to obtain a charging current function curve, and the theoretical current data at a plurality of moments can be fitted to obtain a theoretical current function curve. It can be judged whether the deviation of the current is stable from the viewpoint of continuous data based on the charging current function curve and the theoretical current function curve.

According to one embodiment of the present invention, the current stability score may be determined based on the above-obtained current deviation average value, the current deviation standard deviation, the current deviation maximum value, the charging current function curve, and the theoretical current function curve, thereby determining the stability of the direct current power supply itself based on both discrete and continuous angles.

According to one embodiment of the invention, determining the current stability score from the current deviation average, the current deviation standard deviation, the current deviation maximum, the charging current function curve and the theoretical current function curve comprises:

The current stability score S _I is obtained according to equation (1),

Wherein,For the current deviation average value, Δi _max is the current deviation maximum value, D (Δi) is the current deviation standard deviation, t _s is the start time of the current detection period, t _f is the end time of the current detection period, I _c (t) is the charging current function curve, I _t (t) is the theoretical current function curve, n is the number of times, n is a positive integer, α _I is a preset current stability coefficient, and count is a count function.

In accordance with one embodiment of the present invention,The integral of the difference between the charging current function curve and the theoretical current function curve may be represented, and the smaller the integral value, the closer the charging current function curve and the theoretical current function curve may be represented. The smaller the integral value of the deviation of the two continuous curves is, the closer the charging current data is to the theoretical current data in the continuous time period in the current detection period, and the higher the current stability of the direct current power supply is. The term can be located at the denominator position of the formula (1), so that the larger the solving result of the formula (1), the higher the current stability of the direct current power supply per se.

In accordance with one embodiment of the present invention,The deviation from the number of times the derivative of the difference of the charging current function curve and the theoretical current function curve is equal to 0 may be expressed. The method integrates two angles of continuous data and discrete data to judge whether the charging current data is close to the theoretical current data and whether the current stability of the direct current power supply is higher. I _c(t)-I_t (t) represents the difference between the charging current function curve and the theoretical current function curve, if the difference is always increased, the deviation between the charging current data and the theoretical current data is larger and larger, the current stability of the direct current power supply is not high, if the difference is always reduced, the difference between the charging current data and the theoretical current data is larger at the beginning of the detection period, and then the difference is always reduced, but the moment with the larger difference exists. Therefore, when the difference is increased and decreased, the difference between the two can be kept at a small level all the time, namely, the difference can be decreased after the difference is increased to a certain level or increased again after the difference is decreased to a certain level, and the difference between the two is stable. Based on the above analysis, the derivative of the above difference can be solved, the time when the derivative is equal to 0 representing the time when the difference is alternately increased and decreased, the more times the derivative is equal to 0, the more times the difference is alternately increased and decreased, the less the possibility that the difference is larger. The term may indicate the ratio of the difference between the number of times the derivative is equal to 0 and the total number of times in the current detection period to the total number of times in the current detection period, the larger the ratio, the greater the number of alternations, and the more stable the difference, i.e. the better the current stability.

In accordance with one embodiment of the present invention,The ratio of the maximum value of the current deviation to the average value of the current deviation to the standard deviation of the current deviation is shown, and the larger the ratio is, the more serious the more extreme deviation is, namely, the larger the deviation between the charging current data and the theoretical current data is at a certain or certain moments, and the worse the current stability of the direct current power supply per se is also shown. And (3) placing the term at the denominator position of the formula (1) so that the larger the solving result of the formula (1) is, the higher the current stability of the direct-current power supply is.

According to one embodiment of the present invention, through the above analysis, the formula (1) may describe the current stability of the dc power supply itself from two angles of continuous data and discrete data, the higher the current stability score calculated by the formula (1), the better the current stability of the dc power supply itself, and conversely, the lower the current stability score calculated by the formula (1), the worse the current stability of the dc power supply itself.

In this way, the influence of current fluctuation caused by the battery can be eliminated based on the theoretical current data, so that the current stability of the direct current power supply can be determined based on the difference between the charging current data and the theoretical current data, the current stability of the direct current power supply can be comprehensively judged based on the discrete current deviation data, the continuous charging current function curve and the theoretical current function curve, the current stability score can be solved based on two angles of the discrete data and the continuous data, and the accuracy and objectivity of the current stability score can be improved.

According to one embodiment of the present invention, the above can separately determine the current stability of the dc power supply itself, so that it can be discriminated whether the situation is caused by the dc power supply itself or by the battery when the current is unstable. Further, a battery stability score may also be determined in step S106 to determine whether the battery may cause current instability during charging.

According to one embodiment of the present invention, step S106 may include: determining a rechargeable battery stability score S _C according to formula (2),

Wherein, I _j is charging current data at the j-th moment in the current detection period, β ₁ is a first preset multiple, β ₂ is a second preset multiple, I _R is rated current, T _j is temperature information of the rechargeable battery at the j-th moment in the current detection period, β ₃ is a third preset multiple, T _m is preset safe temperature, n is the number of a plurality of moments, j is less than or equal to n, j and n are positive integers, and count is a counting function.

According to one embodiment of the present invention, the first preset multiple is a value greater than 1, I _j≥β₁I_R may indicate that I _j exceeds the rated current, and the exceeding is large in magnitude, which is liable to cause current overload, and the number of times that this occurs may be determined by a counting function. On the other hand, the second preset multiple is a value smaller than 1, I _j≤β₂I_R may indicate that I _j is smaller than the rated current, and the magnitude of the smaller than the rated current is larger, possibly caused by an impedance abnormality, for example, some circuits are broken, etc., and the number of times of occurrence of the situation can be determined by a counting function. Both of the above cases are cases in which the actually measured charging current data is abnormal, a deviation between the case in which the charging current data is abnormal and the total number of times in the current detection period may be determined, and a ratio between the deviation and the total number of times may be determined. The larger the ratio, the less the case of abnormality of the charging current data, the higher the stability of the rechargeable battery, whereas the smaller the ratio, the more the case of abnormality of the charging current data, the worse the stability of the rechargeable battery.

According to one embodiment of the present invention, the counting function may be further applied to calculate the number of times the temperature information exceeds the safety temperature by a larger magnitude, for example, the number of times the temperature information is calculated to be greater than or equal to the product of a third preset multiple (a value greater than 1) and the safety temperature. That is, a count function is used to calculate the number of occurrences of temperature anomalies. Further, a deviation between the number of times and a total number of times in the current detection period is calculated, and a ratio between the deviation and the total number of times is determined. The larger the ratio, the less the case of temperature abnormality is indicated, and the higher the stability of the rechargeable battery, whereas the smaller the ratio, the more the case of temperature abnormality is indicated, the worse the stability of the rechargeable battery.

According to one embodiment of the present invention, the above two terms are multiplied to obtain the formula (2), and the higher the stability score of the rechargeable battery solved by the formula (2), the better the stability of the rechargeable battery, whereas the lower the stability score of the rechargeable battery solved by the formula (2), the worse the stability of the rechargeable battery.

In this way, the stability of the rechargeable battery can be determined by counting the number of abnormal current and the number of abnormal temperature, and the accuracy and objectivity of the stability score of the rechargeable battery are improved.

According to an embodiment of the present invention, in step S107, a charge safety score of the dc power supply may be determined based on the current stability score and the rechargeable battery stability score obtained above. In an example, since the current stability of the dc power supply itself and the charging stability of the rechargeable battery are two aspects describing the charging safety, the current stability score and the charging stability score may be weighted and summed, or the current stability score and the charging stability score may be multiplied to obtain the charging safety score of the dc power supply.

According to one embodiment of the present invention, in step S108, a time interval between an end time of a current detection period and a start time of a next detection period may be determined based on a charge safety score of the dc power supply. For example, if the charging safety score of the dc power supply is higher, the charging safety is better, and the time interval can be prolonged without too frequent detection, so as to reduce the occupation of the computing resources. On the contrary, if the charging safety score of the direct current power supply is lower, the charging safety is poorer, and the time interval can be shortened, so that the charging safety condition can be known more timely.

According to one embodiment of the present invention, step S108 includes: according to equation (3), the time interval deltat between the end time of the current detection period and the start time of the next detection period is determined,

Wherein Δt _p is a preset time interval, S _s is the charging safety score, and S _T is a preset score threshold.

According to an embodiment of the present invention, the time interval of the two detection periods may be appropriately lengthened or shortened based on the charge safety score obtained above on the basis of a preset time interval. Therefore, the purposes of prolonging the time interval of two detection periods under the condition of higher charge safety scores and shortening the time interval of two detection periods under the condition of lower charge safety scores are achieved.

According to one embodiment of the invention, in the case that the charge safety score is greater than or equal to a preset scoring threshold, the preset time interval may be multiplied by a factor greater than or equal to 1The time interval of the two detection periods is obtained to extend the time interval between the two detection periods in case the charge safety score is greater than or equal to a preset score threshold. And, the higher the charge safety score, the better the charge safety, the longer the time interval of the two detection periods. For example, the preset scoring threshold is 0.6, the charging safety score is 0.6, the time interval of two detection periods is equal to the preset time interval, the charging safety score is 0.8, the time interval of two detection periods is equal to/>The charging safety score is 0.9, and the time interval of the two detection periods is equal to 1.5 times of the preset time interval. The invention does not limit the specific values of the charge safety score and the time interval of the two detection periods.

According to an embodiment of the present invention, in case the charge safety score is smaller than a preset score threshold, the preset time interval may be multiplied by a multiple smaller than 1, i.e. the product of the preset time interval and the charge safety score is taken as the time interval of two detection periods. And, the lower the charge safety score, the worse the charge safety, the shorter the time interval of the two detection periods. For example, the preset scoring threshold is 0.6, the charging safety score is 0.5, the time interval of the two detection periods is equal to 0.5 times of the preset time interval, the charging safety score is 0.3, and the time interval of the two detection periods is equal to 0.3 times of the preset time interval. The invention does not limit the specific values of the charge safety score and the time interval of the two detection periods.

By the method, the time interval between the two detection periods can be set based on the charging safety score, if the charging safety score is greater than or equal to a preset score threshold, the charging safety is good, the time interval can be prolonged without too frequent detection, and therefore the occupation of operation resources is reduced. Otherwise, if the charging safety score of the direct current power supply is smaller than a preset scoring threshold, the charging safety is poor, the time interval can be shortened, and therefore the charging safety condition can be known more timely.

According to the high-power density direct current power supply safety monitoring method provided by the embodiment of the invention, actually collected charging current data at a plurality of moments can be obtained, theoretical current data is determined according to the temperature information of the battery, the influence of the battery is eliminated based on the theoretical current data, the current stability score of the direct current power supply is determined, and the stability score of the charging battery is also determined, so that when the current is unstable, whether the current is caused by the battery or caused by the direct current power supply can be distinguished, the factors of the current instability can be eliminated conveniently, and the charging safety is improved. When the theoretical current data is determined, the theoretical impedance of the rechargeable battery at each temperature can be obtained through the historical data of a plurality of sample batteries with the same specification as the rechargeable battery, so that the theoretical current data of the rechargeable battery at a plurality of moments can be determined, a data basis is provided for eliminating current change factors caused by the rechargeable battery of the battery, and the accuracy of judging the current stability of the direct current power supply can be improved. When the current stability score of the direct current power supply is determined, the influence of current fluctuation caused by a battery can be eliminated based on theoretical current data, so that the current stability of the direct current power supply can be determined based on the difference between charging current data and theoretical current data, the current stability of the direct current power supply can be comprehensively judged based on discrete current deviation data, a continuous charging current function curve and a theoretical current function curve, the current stability score can be solved based on two angles of the discrete data and the continuous data, and the accuracy and objectivity of the current stability score are improved. And the stability of the rechargeable battery can be further determined by counting the abnormal times of the current and the abnormal times of the temperature, so that the accuracy and objectivity of the stability scoring of the rechargeable battery are improved. Further, the time interval between detection periods can be determined based on the charging safety score, the time interval is increased when the charging safety is high, the occupation of processing resources is reduced, the time interval is reduced when the charging safety is low, fault factors are found in time, and the charging safety is improved.

Fig. 2 schematically illustrates a block diagram of a high power density dc power supply safety monitoring system, as shown in fig. 2, according to an embodiment of the invention, the system comprising:

The charging current data module 101 is configured to collect charging current data of the dc power supply at a plurality of moments in a current detection period;

A performance parameter module 102, configured to obtain a performance parameter of a rechargeable battery connected to the dc power supply, where the performance parameter includes an impedance of the rechargeable battery;

a temperature information module 103, configured to collect temperature information of the rechargeable battery at a plurality of moments in the current detection period;

A theoretical current data module 104, configured to determine theoretical current data of the rechargeable battery at a plurality of moments in a current detection period according to the performance parameter of the rechargeable battery, the temperature information of the rechargeable battery, and the voltage data of the dc power supply;

A current stability scoring module 105, configured to determine a current stability score of the dc power supply itself according to the charging current data and the theoretical current data;

A rechargeable battery stability scoring module 106, configured to determine a rechargeable battery stability score according to the charging current data and the temperature information of the rechargeable battery;

a charging safety scoring module 107, configured to determine a charging safety score of a dc power supply according to the current stability score and the rechargeable battery stability score;

a time interval module 108, configured to determine a time interval between an end time of the current detection period and a start time of a next detection period according to the charge safety score.

According to one embodiment of the invention, the theoretical current data module is further configured to:

Selecting a plurality of sample batteries in a sample library according to the performance parameters of the rechargeable batteries, wherein the sample batteries have the same specification as the rechargeable batteries;

determining an average impedance decay function of the plurality of sample cells according to historical temperature data and historical current data at a plurality of historical moments during charging of the plurality of sample cells;

Determining theoretical impedance of the rechargeable battery at a plurality of moments in a current detection period according to the average impedance decay function and temperature information of the rechargeable battery;

and determining theoretical current data of the rechargeable battery at a plurality of moments in the current detection period according to the voltage data of the direct current power supply and the theoretical impedance.

According to one embodiment of the invention, the theoretical current data module is further configured to:

Acquiring historical temperature data and historical current data of a plurality of historical moments during charging of a plurality of sample batteries;

determining a charging voltage during which the plurality of sample cells are charged;

Determining real-time impedance of the plurality of sample batteries at a plurality of historical moments according to the charging voltage and the historical current data;

Determining an impedance decay function of each sample cell according to the historical temperature data and the real-time impedance, wherein the impedance decay function is used for describing the relation between the impedance and the temperature of the sample cell;

an average impedance decay function of the plurality of sample cells is determined based on the impedance decay functions of the respective sample cells.

According to one embodiment of the invention, the current stability scoring module is further configured to:

Acquiring current deviation data between charging current data and theoretical current data at a plurality of moments in the current detection period;

Determining a current deviation average value, a current deviation standard deviation and a current deviation maximum value according to the current deviation data;

Fitting the charging current data at a plurality of moments in the current detection period to obtain a charging current function curve;

fitting theoretical current data at a plurality of moments in the current detection period to obtain a theoretical current function curve;

and determining the current stability score according to the current deviation average value, the current deviation standard deviation, the current deviation maximum value, the charging current function curve and the theoretical current function curve.

According to one embodiment of the invention, the current stability scoring module is further configured to:

According to the formula

The current stability score is obtained S _I, wherein,For the current deviation average value, Δi _max is the current deviation maximum value, D (Δi) is the current deviation standard deviation, t _s is the start time of the current detection period, t _f is the end time of the current detection period, I _c (t) is the charging current function curve, I _t (t) is the theoretical current function curve, n is the number of times, n is a positive integer, α _I is a preset current stability coefficient, and count is a count function.

According to one embodiment of the present invention, the rechargeable battery stability scoring module is further configured to:

According to the formula

Determining a stability score S _C of the rechargeable battery, wherein I _j is charging current data of the jth moment in the current detection period, beta ₁ is a first preset multiple, beta ₂ is a second preset multiple, I _R is rated current, T _j is temperature information of the rechargeable battery of the jth moment in the current detection period, beta ₃ is a third preset multiple, T _m is preset safe temperature, n is the number of a plurality of moments, j is less than or equal to n, j and n are positive integers, and count is a counting function.

According to one embodiment of the invention, the time interval module is further configured to:

According to the formula

And determining a time interval delta t between the ending time of the current detection period and the starting time of the next detection period, wherein delta t _p is a preset time interval, S _s is the charge safety score, and S _T is a preset scoring threshold.

According to one embodiment of the present invention, there is provided a high power density dc power supply safety monitoring device including: a processor; a memory for storing processor-executable instructions; wherein the processor is configured to invoke the instructions stored by the memory to perform the high power density dc power supply safety monitoring method.

According to one embodiment of the present invention, a computer readable storage medium having stored thereon computer program instructions which, when executed by a processor, implement the high power density dc power supply safety monitoring method is provided.

The present invention may be a method, apparatus, system, and/or computer program product. The computer program product may include a computer readable storage medium having computer readable program instructions embodied thereon for performing various aspects of the present invention.

It will be appreciated by persons skilled in the art that the embodiments of the invention described above and shown in the drawings are by way of example only and are not limiting. The objects of the present invention have been fully and effectively achieved. The functional and structural principles of the present invention have been shown and described in the examples and embodiments of the invention may be modified or practiced without departing from the principles described.

Finally, it should be noted that: the above embodiments are only for illustrating the technical solution of the present invention, and not for limiting the same; although the invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some or all of the technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit of the invention.

Claims (4)

1. The high power density direct current power supply safety monitoring method is characterized by comprising the following steps of:

Collecting charging current data of a direct current power supply at a plurality of moments in a current detection period;

acquiring performance parameters of a rechargeable battery connected with the direct current power supply, wherein the performance parameters comprise impedance of the rechargeable battery;

collecting temperature information of the rechargeable battery at a plurality of moments in the current detection period;

Determining theoretical current data of the rechargeable battery at a plurality of moments in a current detection period according to the performance parameters of the rechargeable battery, the temperature information of the rechargeable battery and the voltage data of the direct current power supply;

determining a current stability score of the direct current power supply according to the charging current data and the theoretical current data;

Determining a stability score of the rechargeable battery according to the charging current data and the temperature information of the rechargeable battery;

Determining a charging safety score of a direct current power supply according to the current stability score and the rechargeable battery stability score;

determining a time interval between the end time of the current detection period and the start time of the next detection period according to the charging safety score;

Determining a current stability score of the direct current power supply according to the charging current data and the theoretical current data, including:

Acquiring current deviation data between charging current data and theoretical current data at a plurality of moments in the current detection period;

Determining a current deviation average value, a current deviation standard deviation and a current deviation maximum value according to the current deviation data;

Fitting the charging current data at a plurality of moments in the current detection period to obtain a charging current function curve;

fitting theoretical current data at a plurality of moments in the current detection period to obtain a theoretical current function curve;

Determining the current stability score according to the current deviation average value, the current deviation standard deviation, the current deviation maximum value, the charging current function curve and the theoretical current function curve;

determining the current stability score from the current deviation average, the current deviation standard deviation, the current deviation maximum, the charging current function curve, and the theoretical current function curve, comprising:

According to the formula

The current stability score is obtained S _I, wherein,For the current deviation average value, Δi _max is the current deviation maximum value, D (Δi) is the current deviation standard deviation, t _s is the start time of the current detection period, t _f is the end time of the current detection period, I _c (t) is the charging current function curve, I _t (t) is the theoretical current function curve, n is the number of times, n is a positive integer, α _I is a preset current stability coefficient, and count is a count function;

determining a rechargeable battery stability score according to the charging current data and the temperature information of the rechargeable battery, comprising:

According to the formula

Determining a stability score S _C of the rechargeable battery, wherein I _j is charging current data of the jth moment in the current detection period, beta ₁ is a first preset multiple, beta ₂ is a second preset multiple, I _R is rated current, T _j is temperature information of the rechargeable battery of the jth moment in the current detection period, beta ₃ is a third preset multiple, T _m is preset safe temperature, n is the number of a plurality of moments, j is less than or equal to n, j and n are positive integers, and count is a counting function;

Determining, according to the charge safety score, a time interval between an end time of the current detection period and a start time of a next detection period, including:

According to the formula

Determining a time interval delta t between the ending time of the current detection period and the starting time of the next detection period, wherein delta t _p is a preset time interval, S _s is the charge safety score, and S _T is a preset scoring threshold;

determining a charging safety score of a direct current power supply according to the current stability score and the rechargeable battery stability score, including:

and carrying out weighted summation on the current stability score and the rechargeable battery stability score, or multiplying the current stability score and the rechargeable battery stability score to obtain the charging safety score of the direct-current power supply.

2. The method of claim 1, wherein determining theoretical current data for the rechargeable battery at a plurality of times during a current detection period based on the performance parameter of the rechargeable battery, the temperature information of the rechargeable battery, and the voltage data of the dc power supply, comprises:

Selecting a plurality of sample batteries in a sample library according to the performance parameters of the rechargeable batteries, wherein the sample batteries have the same specification as the rechargeable batteries;

determining an average impedance decay function of the plurality of sample cells according to historical temperature data and historical current data at a plurality of historical moments during charging of the plurality of sample cells;

Determining theoretical impedance of the rechargeable battery at a plurality of moments in a current detection period according to the average impedance decay function and temperature information of the rechargeable battery;

and determining theoretical current data of the rechargeable battery at a plurality of moments in the current detection period according to the voltage data of the direct current power supply and the theoretical impedance.

3. The method of claim 2, wherein determining the average impedance decay function for the plurality of sample cells based on historical temperature data and historical current data for a plurality of historical moments during charging of the plurality of sample cells comprises:

Acquiring historical temperature data and historical current data of a plurality of historical moments during charging of a plurality of sample batteries;

determining a charging voltage during which the plurality of sample cells are charged;

Determining real-time impedance of the plurality of sample batteries at a plurality of historical moments according to the charging voltage and the historical current data;

Determining an impedance decay function of each sample cell according to the historical temperature data and the real-time impedance, wherein the impedance decay function is used for describing the relation between the impedance and the temperature of the sample cell;

an average impedance decay function of the plurality of sample cells is determined based on the impedance decay functions of the respective sample cells.

4. A high power density dc power supply safety monitoring system for performing the method of any one of claims 1-3, comprising:

The charging current data module is used for collecting charging current data of the direct-current power supply at a plurality of moments in the current detection period;

The performance parameter module is used for acquiring the performance parameter of the rechargeable battery connected with the direct-current power supply, wherein the performance parameter comprises the impedance of the rechargeable battery;

The temperature information module is used for collecting temperature information of the rechargeable battery at a plurality of moments in the current detection period;

the theoretical current data module is used for determining theoretical current data of the rechargeable battery at a plurality of moments in a current detection period according to the performance parameters of the rechargeable battery, the temperature information of the rechargeable battery and the voltage data of the direct current power supply;

the current stability scoring module is used for determining the current stability score of the direct current power supply according to the charging current data and the theoretical current data;

The rechargeable battery stability scoring module is used for determining the stability score of the rechargeable battery according to the charging current data and the temperature information of the rechargeable battery;

The charging safety scoring module is used for determining the charging safety score of the direct-current power supply according to the current stability score and the rechargeable battery stability score;

And the time interval module is used for determining the time interval between the ending time of the current detection period and the starting time of the next detection period according to the charging safety score.