CN118432233B - Storage battery monitoring method and control system - Google Patents

Abstract

The invention relates to the technical field of storage battery monitoring, and particularly discloses a storage battery monitoring method and a control system. Acquiring real-time current data of each single storage battery of the battery pack in a floating state according to a discrete sampling method, and acquiring a time interval of the real-time current data of each single storage battery; acquiring a corresponding first real-time SOC estimated value according to the real-time current data and the time interval of each single storage battery; judging whether the SOC estimation value of each single storage battery is balanced or not; and if the balance is unbalanced, carrying out SOC balance on each single storage battery. By means of timely balance control and online activation treatment, the method can reduce performance difference and aging speed of the single storage battery, so that the overall service life of the battery pack is prolonged, and the performance of the single storage battery and the monitoring accuracy of the overall performance of the battery pack are effectively improved through real-time monitoring, comprehensive evaluation and online activation treatment modes.

Description

Storage battery monitoring method and control system

Technical Field

The invention relates to the technical field of storage battery monitoring, in particular to a storage battery monitoring method and system.

Background

The storage battery is a device for directly converting chemical energy into electric energy, is a battery designed to be rechargeable, realizes recharging through reversible chemical reaction, and is usually referred to as a lead-acid storage battery, which is one of the batteries, belongs to a secondary battery, the existing lead-acid storage battery knows the residual electric quantity condition of the battery through an SOC (State of Charge) so as to reasonably arrange the use and charging strategy of the battery, and the common meaning of the SOC is "State of Charge", namely the Charge State of the battery, and represents the proportion of the residual electric quantity in the battery to the total capacity of the battery.

When the existing storage battery pack is in a floating charge state for a long time, due to performance differences among the single storage batteries, the SOC of the different storage batteries is deviated, so that misjudgment is easy to occur when the different single storage batteries are subjected to balanced monitoring, excessive activation or insufficient activation is easy to occur when the misjudged single storage batteries are activated, the aging speed of the single storage batteries is increased, and the overall service life of the battery pack is reduced.

Disclosure of Invention

The invention aims to provide a storage battery monitoring method for solving the technical problems in the background technology.

In order to achieve the above purpose, the present invention provides the following technical solutions:

A battery monitoring method comprising:

acquiring real-time current data of each single storage battery of the battery pack in a floating state according to a discrete sampling method, and acquiring a time interval of the real-time current data of each single storage battery;

Acquiring a first real-time SOC estimated value according to the real-time current data and the time interval;

Judging whether the first real-time SOC estimation value of each single storage battery is in a preset interval or not, and taking all the single storage batteries which are not in the preset interval as adjustment target batteries;

Performing balance adjustment on an adjustment target battery, wherein the balance adjustment comprises passive balance adjustment, active charge balance and active discharge balance;

acquiring a first SOC balance speed change value of each regulation target battery in passive balance regulation;

acquiring a second SOC balance speed change value of each adjustment target battery in active charge balance;

acquiring a third SOC balance speed change value of each adjustment target battery in active discharge balance;

calculating a performance evaluation value of the adjustment target battery according to the first SOC balance speed change value, the second SOC balance speed change value and the third SOC balance speed change value;

judging whether the performance evaluation value is larger than a preset value or not;

And if at least one performance evaluation value of the adjustment target battery is larger than a preset value, performing on-line shallow charging and shallow discharging activation on the corresponding adjustment target battery larger than the preset value.

Preferably, the step of obtaining the first real-time SOC estimation value according to the real-time current data and the time interval includes:

acquiring an initial preset SOC value of each single storage battery;

acquiring real-time current data of each single storage battery;

acquiring the rated capacity value of each single storage battery;

Acquiring a sampling time interval of each single storage battery, wherein the sampling time interval comprises a starting time point and an ending time point;

Obtaining the charge and discharge efficiency value of each single storage battery:

Calculating a first real-time SOC estimation value according to an initial preset SOC value, an rated capacity value, real-time current data, a time interval and a charge and discharge efficiency value, wherein a calculation formula is as follows:

；

wherein, A first real-time SOC estimate for the kth battery cell,For the initial preset SOC-value(s),For the rated capacity value of the kth cell,Is the charge and discharge efficiency value of the kth single storage battery,Is the real-time current data of the kth single storage battery,For the starting point in time of the sampling time interval,Is the end time point of the sampling time interval.

Preferably, the step of performing equalization adjustment on the program label cell includes:

taking an adjusting target battery larger than a preset interval as a first single battery;

taking the regulation target battery smaller than the preset interval as a second single battery;

Constructing a first topological circuit for all the first single batteries;

constructing a second topological circuit for all the second single batteries;

Obtaining a maximum preset value of a preset interval;

Acquiring a first difference value between a first real-time SOC estimated value corresponding to each first single battery and a maximum preset value;

carrying out passive balance adjustment on the first single batteries, and transmitting the electric energy corresponding to the first difference value of each first single battery to the energy storage element;

Acquiring a minimum preset value of a preset interval;

Acquiring a second difference value between a first real-time SOC estimated value corresponding to each second single battery and a minimum preset value;

the energy storage element transmits electric energy to the second topological circuit, and performs passive equalization adjustment on a second single battery corresponding to the second topological circuit based on a second difference value;

acquiring a preset SOC charge balance value;

Performing active charge equalization on all the first single batteries and all the second single batteries based on a first preset SOC charge equalization value;

Acquiring a preset SOC discharge balance value;

And performing active discharge equalization on all the first single batteries and all the second single batteries based on a preset SOC discharge equalization value.

Preferably, the step of acquiring the first SOC balance speed change value of each adjustment target battery in the passive balance adjustment includes:

acquiring a first change time period of passive equalization adjustment of each adjustment target battery;

acquiring a plurality of first sampling time points according to a first change time period;

establishing a first SOC trend change chart of each regulation target battery according to a plurality of first sampling time points;

acquiring a first slope change value of each adjustment target battery at a first sampling time point according to a first SOC trend change chart;

And calculating according to the first slope change values corresponding to all the first sampling time points to obtain a first SOC balance speed change value.

Preferably, the step of acquiring the second SOC balance speed variation value of each adjustment target battery in the active charge balance includes:

acquiring a second real-time SOC estimated value of each adjusted target battery after passive equalization adjustment;

performing active charge equalization on each regulation target battery;

Acquiring a second change time period from a second real-time SOC estimated value to a preset SOC charge balance value of each regulation target battery;

Acquiring a plurality of second sampling time points according to the second change time period;

Establishing a second SOC trend change map of each regulation target battery according to a plurality of second sampling time points;

Acquiring a second slope change value of each adjustment target battery at a second sampling time point according to a second SOC trend change chart;

and calculating according to the second slope change value corresponding to the second sampling time point to obtain a second SOC balance speed change value.

Preferably, the step of calculating the performance evaluation value of the adjustment target battery according to the first SOC balance speed change value, the second SOC balance speed change value, and the third SOC balance speed change value includes:

acquiring a first SOC balance speed change value of each regulation target battery;

acquiring a first weight value of a first SOC balance speed change value;

Acquiring a second SOC balance speed change value of each regulation target battery;

acquiring a second weight value of a second SOC balance speed change value;

acquiring a third SOC balance speed change value of each regulation target battery;

Acquiring a third weight value of a third SOC balance speed change value;

calculating the performance evaluation value of each single storage battery according to the first SOC balance speed change value, the first weight value, the second SOC balance speed change value, the second weight value, the third SOC balance speed change value and the third weight value, wherein the calculation formula is as follows:

；

wherein P is an evaluation value of the performance of the single storage battery, a is a variation value of the passive equalization speed of the SOC, B is a first weight value, b is a first SOC active equalization speed variation value,C is a second weight value, c is a second SOC autonomous equalizing speed variation value,Is a third weight value.

The invention also provides a monitoring system of the storage battery, which comprises:

the first acquisition module is used for acquiring real-time current data of each single storage battery in a floating state of the battery pack according to a discrete sampling method and acquiring a time interval of the real-time current data of each single storage battery;

The second acquisition module is used for acquiring a first real-time SOC estimated value according to the real-time current data and the time interval;

the first judging module is used for judging whether the first real-time SOC estimated value of each single storage battery is in a preset interval or not, and taking all the single storage batteries which are not in the preset interval as adjustment target batteries;

The adjusting module is used for carrying out balance adjustment on the adjustment target battery, wherein the balance adjustment comprises passive balance adjustment, active charge balance and active discharge balance;

a third acquisition module for acquiring a first SOC balance speed change value of each adjustment target battery in passive balance adjustment;

a fourth acquisition module for acquiring a second SOC equalization speed variation value of each adjustment target battery in the active charge equalization;

A fifth acquisition module for acquiring a third SOC equalization speed variation value of each adjustment target battery in the active discharge equalization;

The calculation module is used for calculating a performance evaluation value of the adjustment target battery according to the first SOC balance speed change value, the second SOC balance speed change value and the third SOC balance speed change value;

The second judging module is used for judging whether the performance evaluation value is larger than a preset value or not;

And if at least one performance evaluation value of the adjustment target battery is larger than a preset value, performing on-line shallow charging and shallow discharging activation on the corresponding adjustment target battery larger than the preset value.

Preferably, the second obtaining module includes:

A first obtaining unit, configured to obtain an initial preset SOC value of each unit battery;

The second acquisition unit is used for acquiring real-time current data of each single storage battery;

A third acquisition unit for acquiring a rated capacity value of each of the single batteries;

A fourth acquisition unit configured to acquire a sampling time interval of each unit battery, where the sampling time interval includes a start time point and an end time point;

a fifth acquisition unit configured to acquire a charge-discharge efficiency value of each of the battery cells:

The first calculating unit is used for calculating a first real-time SOC estimated value according to an initial preset SOC value, a rated capacity value, real-time current data, a time interval and a charge-discharge efficiency value, wherein a calculation formula is as follows:

；

wherein, For the first real-time SOC estimate value,For the initial preset SOC-value(s),As the value of the rated capacity,In order to obtain the charge-discharge efficiency value,For the real-time current data,In order to start the time point of the time interval,Is the time point at which the time interval ends.

Preferably, the adjusting module includes:

the first marking unit is used for taking the adjusting target battery which is larger than a preset interval as a first single battery;

a second marking unit, configured to take an adjustment target battery smaller than a preset interval as a second unit battery;

The first construction unit is used for constructing a first topological circuit for all the first single batteries;

The second construction unit is used for constructing a second topological circuit for all the second single batteries;

A sixth obtaining unit, configured to obtain a maximum preset value of the preset interval;

A seventh obtaining unit, configured to obtain a first difference between a first real-time SOC estimation value corresponding to each first unit cell and a maximum preset value;

The first adjusting unit is used for carrying out passive balance adjustment on the first single batteries and transmitting the electric energy corresponding to the first difference value of each first single battery to the energy storage element;

an eighth obtaining unit, configured to obtain a minimum preset value of a preset interval;

a ninth obtaining unit, configured to obtain a second difference value between the first real-time SOC estimation value corresponding to each second unit cell and a minimum preset value;

The second adjusting unit is used for transmitting the electric energy to the second topological circuit by the energy storage element and carrying out passive balanced adjustment on a second single battery corresponding to the second topological circuit based on a second difference value;

A tenth acquisition unit configured to acquire a preset SOC charge equalization value;

the third adjusting unit is used for actively equalizing charge of all the first single batteries and all the second single batteries based on the first preset SOC charge equalization value;

an eleventh acquisition unit for acquiring a preset SOC discharge equalization value;

And the fourth adjusting unit is used for actively discharging and balancing all the first single batteries and all the second single batteries based on a preset SOC discharging and balancing value.

Preferably, the computing module includes:

a twelfth acquisition unit for acquiring a first SOC balance speed change value of each adjustment target battery;

a thirteenth acquisition unit configured to acquire a first weight value of the first SOC equalization speed variation value;

a fourteenth acquisition unit configured to acquire a second SOC-equalization-speed variation value for each adjustment target battery;

A fifteenth acquisition unit configured to acquire a second weight value of the second SOC equalization speed variation value;

A sixteenth acquisition unit configured to acquire a third SOC balance speed change value for each adjustment target battery;

A seventeenth obtaining unit, configured to obtain a third weight value of the third SOC equalization speed variation value;

A second calculating unit, configured to calculate each single battery performance evaluation value according to the first SOC equalization speed variation value, the first weight value, the second SOC equalization speed variation value, the second weight value, the third SOC equalization speed variation value, and the third weight value, where the calculation formula is:

；

wherein P is an evaluation value of the performance of the single storage battery, a is a variation value of the passive equalization speed of the SOC, B is a first weight value, b is a first SOC active equalization speed variation value,C is a second weight value, c is a second SOC autonomous equalizing speed variation value,Is a third weight value.

The beneficial effects of the application are as follows: the method comprises the steps of acquiring current data of a single storage battery in real time through a discrete sampling method, estimating an SOC value according to the current data, realizing real-time monitoring of a battery state, effectively avoiding performance decline and potential safety hazards of a battery pack caused by overlarge SOC difference of the single storage battery when the single storage battery is detected, constructing a first SOC trend change chart, a second SOC trend change chart and a third SOC trend change chart, calculating corresponding first SOC equilibrium speed change value, second SOC equilibrium speed change value and third SOC equilibrium speed change value, obtaining a performance evaluation value through the first SOC equilibrium speed change value, the second SOC equilibrium speed change value and the third SOC equilibrium speed change value, comprehensively evaluating the performance of the single storage battery under passive equilibrium adjustment and active equilibrium through the performance evaluation value, finally evaluating through the performance evaluation value, judging whether the corresponding adjustment target battery needs on-line shallow charge and shallow discharge activation, activating active substances in the battery through on-line shallow charge and shallow discharge activation, recovering the activity, and prolonging the service life of the battery.

Drawings

FIG. 1 is a schematic flow chart of the method of the present application.

Fig. 2 is a schematic diagram of a system structure according to the present application.

Fig. 3 is a passive equalization adjustment chart of the adjustment target battery of the present application.

Fig. 4 is an active charge balance diagram of a conditioning target battery according to the present application.

Fig. 5 is a graph showing the active discharge balance of the regulation target battery according to the present application.

The achievement of the objects, functional features and advantages of the present application will be further described with reference to the accompanying drawings, in conjunction with the embodiments.

Detailed Description

It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the invention.

As shown in fig. 1, the present application provides a method for monitoring a storage battery, comprising:

s1, acquiring real-time current data of each single storage battery of a battery pack in a floating state according to a discrete sampling method, and acquiring a time interval of the real-time current data of each single storage battery;

s2, acquiring a first real-time SOC estimated value according to the real-time current data and the time interval;

s3, judging whether the first real-time SOC estimation value of each single storage battery is in a preset interval or not, and taking all the single storage batteries which are not in the preset interval as adjustment target batteries;

s4, balancing adjustment is carried out on the program label battery, wherein the balancing adjustment comprises passive balancing adjustment, active charge balancing and active discharge balancing;

s5, acquiring a first SOC balance speed change value of each regulation target battery in passive balance regulation;

s6, acquiring a second SOC balance speed change value of each adjustment target battery in active charge balance;

s7, obtaining a third SOC balance speed change value of each adjustment target battery in active discharge balance;

s8, calculating a performance evaluation value of the adjustment target battery according to the first SOC balance speed change value, the second SOC balance speed change value and the third SOC balance speed change value;

S9, judging whether the performance evaluation value is larger than a preset value or not;

And if at least one performance evaluation value of the adjustment target battery is larger than a preset value, performing on-line shallow charging and shallow discharging activation on the corresponding adjustment target battery larger than the preset value.

As described in the above steps S1-S9, various machine rooms are built in large numbers, a large number of storage batteries are used in ensuring the backup power supply of the machine room, a large number of storage battery packs are used in ensuring the backup power supply of the machine room, the storage battery packs are usually formed by connecting a plurality of single storage batteries in series or in parallel, and due to different manufacturing processes, use environments and aging degrees, performance differences exist among the single storage batteries, which may cause the overall performance of the battery packs to be reduced, during the use process of the battery packs, the battery packs can undergo various working conditions such as charging, discharging, standing (floating state) and the like, in the floating state, single storage batteries in the backup storage battery packs may show different performance characteristics due to manufacturing differences, use environments, aging speeds and other various factors, meanwhile, the battery packs do not perform charging and discharging operations, but the single storage batteries may generate imbalance of the SOC (state of charge) due to different self-discharging rates. The unbalanced state not only can influence the overall performance of the battery pack, but also can accelerate the aging of the single storage battery, when the SOC of each storage battery is monitored and tracked, errors can occur in the monitoring result due to the performance differences, errors can occur in the equalization effect due to the errors of the previous SOC monitoring during the subsequent equalization operation of the storage battery, the unbalanced storage battery pack can lead to unstable voltage of the whole battery pack, even the overcharge or overdischarge condition of the individual storage battery can be caused, the overcharge or overdischarge condition not only accelerates the aging of the storage battery, but also can lead to the crystallization of electrolyte in the storage battery to influence the efficiency and the service life of the storage battery;

The invention acquires the real-time current data of each single storage battery in a floating state of the battery pack by a discrete sampling method, the discrete sampling method can acquire the real-time current data of each single storage battery periodically or according to a certain rule, thereby realizing accurate monitoring of the performance of the battery pack, simultaneously recording the time interval of the real-time current data of each single storage battery, acquiring a corresponding real-time SOC (state of charge) estimated value by the real-time current data and the time interval of each single storage battery, the first real-time SOC estimated value can accurately reflect the current state of each single storage battery, in the battery pack, the charge and discharge performance difference of the single storage battery can lead to the imbalance of the SOC, Then monitoring the SOC of the single storage battery in real time, if the first real-time SOC estimated value of one single storage battery is not in a preset interval, judging that the performance of the single storage battery is changed, taking all the single storage batteries which are not in the preset interval as adjustment target batteries, then carrying out passive equalization adjustment and active discharge equalization on the adjustment target batteries, obtaining the first SOC equalization speed change value of each adjustment target battery under the passive equalization adjustment, obtaining the second SOC equalization speed change value of each adjustment target battery in the active charge equalization and the third SOC equalization speed change value of each adjustment target battery in the active discharge equalization, Then calculating the performance evaluation value of the adjustment target battery through the first SOC balance speed change value, the second SOC balance speed change value and the third SOC balance speed change value, and comparing the performance evaluation values of different adjustment program standard batteries to evaluate the performance difference between the adjustment target battery and the third SOC balance speed change value, so that the monitoring and evaluation precision of the adjustment target battery in a floating charge state can be improved; after passive equalization adjustment is carried out on each adjustment target battery, active charge equalization is carried out, the SOC change of each adjustment target battery in the active charge equalization process can be accurately monitored, the equalization speed of each adjustment target battery in the active charge equalization process can be reflected through a second SOC equalization speed change value, the charge equalization efficiency and effect of different adjustment program standard batteries can be evaluated through comparison of second SOC equalization speed change values of different adjustment program standard batteries, and if the second SOC equalization speed change value of each adjustment target battery appears too fast, the adjustment target battery is judged to have charge saturation, and the situation of overcharging of a single storage battery is prevented; Then active discharge equalization is carried out, the energy difference between the adjustment target batteries can be prevented from being too large through the active discharge equalization, so that the energy utilization efficiency of the whole battery pack is improved, then a third SOC equalization speed change value is obtained based on the data of the active discharge equalization, the performance of the single storage battery in the discharging process can be further known through the third SOC equalization speed change value, the performance of the single storage battery in the discharging process comprises discharging speed, discharging efficiency and the like, the performance evaluation value of each adjustment target battery is calculated by obtaining the first SOC equalization speed change value, the second SOC equalization speed change value and the third SOC equalization speed change value, the performance of the regulation target battery under different working conditions can be comprehensively considered, the charge and discharge efficiency and the balance capacity of the regulation target battery can be more accurately known by comparing and analyzing the SOC speed change values under different balance states, and finally, the evaluation is carried out by the performance evaluation value to judge whether the corresponding regulation target battery needs to be subjected to on-line shallow charge and shallow discharge activation or not, and the active substances in the battery are activated by the on-line shallow charge and shallow discharge activation, so that the activity of the battery is recovered, and the service life of the battery is prolonged.

In one embodiment, the step of obtaining the corresponding first real-time SOC estimation value according to the real-time current data and the time interval of each battery cell includes:

S201, acquiring an initial preset SOC value of each single storage battery;

s202, acquiring real-time current data of each single storage battery;

S203, acquiring the rated capacity value of each single storage battery;

s204, acquiring a sampling time interval of each single storage battery, wherein the sampling time interval comprises a starting time point and an ending time point;

S205, acquiring a charge and discharge efficiency value of each single storage battery;

S206, calculating a first real-time SOC estimation value according to an initial preset SOC value, a rated capacity value, real-time current data, a time interval and a charge and discharge efficiency value, wherein a calculation formula is as follows:

；

wherein, For the first real-time SOC estimate value,For the initial preset SOC-value(s),As the value of the rated capacity,In order to obtain the charge-discharge efficiency value,For the real-time current data,In order to start the time point of the time interval,Is the time point at which the time interval ends.

As described in the above steps S201 to S206, by comprehensively considering the initial preset SOC value, the rated capacity value, the real-time current data, the time interval, and the charge/discharge efficiency value, the current SOC value of the battery cell can be estimated more accurately,

For example: initial preset SOC value (Socm): assume 80%

Rated volume value [ ]): Assume 100Ah (Anshi)

Real-time current data [ ]): Assume to be-5A (discharge is negative and charge is positive)

Time interval [ ]，): Assume 1 hour

Charging and discharging efficiency value [ ]): Assuming 0.9 (i.e. 90% efficiency),

The data are taken into the formula to calculate:

= 80% + (1/100Ah) * 0.9 * (-5A) * 1h

= 79.55%

Therefore, after 1 hour of discharge, the first real-time SOC estimate of the battery drops to 79.55%.

The acquisition of the real-time current data enables the SOC estimation value to be updated in real time, so that the state of charge of the battery at different moments is reflected, the situation that the battery is overcharged or overdischarged in the follow-up process is possibly caused in the monitoring process if the SOC estimation is inaccurate is prevented, the reliability of the estimation result can be improved by comprehensively considering a plurality of parameters to carry out the SOC estimation, and even if errors or fluctuation exists in one parameter, other parameters can be compensated and corrected to a certain extent, so that the stability of the SOC estimation value is maintained.

In one embodiment, as shown in fig. 3, the step of performing equalization adjustment on the program label cell includes:

S401, taking an adjusting target battery larger than a preset interval as a first single battery;

s402, taking the regulation target battery smaller than a preset interval as a second single battery;

S403, constructing a first topological circuit for all the first single batteries;

s404, constructing a second topological circuit for all the second single batteries;

S405, acquiring a maximum preset value of a preset interval;

s406, obtaining a first difference value between a first real-time SOC estimated value corresponding to each first single battery and a maximum preset value;

S407, carrying out passive balance adjustment on the first single batteries, and transmitting the electric energy corresponding to the first difference value of each first single battery to the energy storage element;

s408, acquiring a minimum preset value of a preset interval;

S409, obtaining a second difference value between the first real-time SOC estimated value corresponding to each second single battery and a minimum preset value;

s410, the energy storage element transmits electric energy to the second topological circuit, and the second single battery corresponding to the energy storage element is subjected to passive balance adjustment based on a second difference value;

S411, acquiring a preset SOC charge balance value;

s412, performing active charge equalization on all the first single batteries and all the second single batteries based on the first preset SOC charge equalization value;

s413, acquiring a preset SOC discharge balance value;

And S414, performing active discharge equalization on all the first single batteries and all the second single batteries based on a preset SOC discharge equalization value.

As described in the above steps S401-S414, the first single cell is used as the adjustment target cell of the overcharged state and the second single cell is used as the adjustment target cell of the desired state of charge, the first topology circuit is constructed for all the first single cells, the redundant electric energy is delivered to the energy storage element through the first topology circuit, the redundant electric energy is recycled through the energy storage element and delivered to the second topology circuit, the electric energy is supplemented for all the second single cells through the second topology circuit, so as to reduce the balance loss, increase the balance speed and reduce the complexity of the system structure, and the problems that the expansibility of the adjustment target cell is poor or the existing electric energy is not suitable for being applied to the adjustment target cells of different initial cell SOC levels and different capacities can be solved, the passive balance adjustment enables the electric quantity States (SOCs) of all the adjustment target cells to be closer, the overall performance of the battery pack, such as the output power, the charging speed and the discharging speed, etc., the active adjustment target cells are balanced, the load of all the adjustment target cells can be shared more evenly, and the active adjustment target cells can be prevented from being balanced, and the difference of the active adjustment target cells can be avoided.

In one embodiment, as shown in fig. 3, the obtaining the first SOC balance speed variation value of each adjustment target battery in the passive balance adjustment includes:

s501, acquiring a first change time period of passive equalization adjustment of each adjustment target battery;

s502, acquiring a plurality of first sampling time points according to a first change time period;

s503, establishing a first SOC trend change chart of each regulation target battery according to a plurality of first sampling time points;

S504, acquiring a first slope change value of each adjustment target battery at a first sampling time point according to a first SOC trend change chart;

s505, calculating according to the first slope change values corresponding to all the first sampling time points to obtain a first SOC balance speed change value.

As described in the above steps S501-S505, by obtaining the first change period of the passive equalization adjustment of each adjustment target battery, the first change period represents the duration of the passive equalization adjustment of each adjustment target battery, then obtaining a plurality of first sampling time points according to the first change period, and taking the plurality of first sampling time points as the abscissa, the first real-time SOC estimation values corresponding to the plurality of first sampling time points as the ordinate to establish a first SOC trend change map, obtaining the first slope change value corresponding to each first sampling time point according to the first SOC trend change map, calculating the average value of the first slope change values corresponding to all first sampling time points, taking the average value as the first SOC equalization speed change value, and by obtaining the first SOC equalization speed change values of all adjustment target batteries, the rate change of each adjustment target battery in the passive equalization process can be known, so as to optimize the equalization strategy, for example, for the adjustment target battery with a slower equalization rate, more positive equalization measures can be taken, the speed of the SOC equalization target battery can be accelerated, meanwhile, the SOC passive sampling speed change value can reflect the state of the adjustment target battery, the first slope change value corresponding to the first sampling time change value, the first sampling time point can be detected, the current change value can be detected, and the current state of the adjustment target battery can be reduced, and the current can be detected, and the current can be reduced by the current change of the adjustment target battery can be detected, and the current can be reduced by the equalization target battery can be detected, and has the current can be detected.

In one embodiment, as shown in fig. 4, the step of obtaining the second SOC balance speed variation value of each adjustment target battery in the active charge balance includes:

s601, obtaining a second real-time SOC estimated value of each adjusted target battery after passive equalization adjustment;

s602, performing active charge equalization on each regulation target battery;

S603, obtaining a second change time period from a second real-time SOC estimation value to a preset SOC charge balance value of each regulation target battery;

s604, acquiring a plurality of second sampling time points according to a second change time period;

s605, a second SOC trend change chart of each adjusting target battery is established according to a plurality of second sampling time points;

s606, acquiring a second slope change value of each adjustment target battery at a second sampling time point according to a second SOC trend change graph;

s607, calculating according to the second slope change value corresponding to the second sampling time point to obtain a second SOC balance speed change value.

As described in the above steps S601-S607, by obtaining the second real-time SOC estimation value of each adjustment target battery after passive equalization adjustment, determining the SOC of each adjustment target battery before active charge equalization through the second real-time SOC estimation value, defining the charge target to be reached by each adjustment target battery through the preset SOC charge equalization value, obtaining the second change time period from the second real-time SOC estimation value to the preset SOC charge equalization value of each adjustment target battery, accurately evaluating the time required for the change of the adjustment target battery from the second real-time SOC estimation value to the preset SOC charge equalization value, obtaining the second real-time SOC estimation value corresponding to the second real-time SOC estimation value through a plurality of second sampling time points, accurately knowing the change of the charge speed of each adjustment target battery during active charge equalization, then establishing a second SOC trend change map according to each adjustment target battery, obtaining the second slope change value corresponding to each second sampling time point according to the second SOC trend change map, and calculating the second SOC change value of the adjustment target battery according to the second slope change value corresponding to the second sampling time point, thus the second SOC change value reflecting the change of the charge speed of the adjustment target battery. By monitoring these change values for a long period of time, performance parameters such as the charging capacity and capacity recovery of the battery can be predicted, and by precisely controlling the charging process of each single storage battery, the charging energy can be utilized to the maximum extent, the energy loss can be reduced, and the charging efficiency can be improved. This helps to reduce charging time, reduce charging costs, and extend the life of the battery.

The step of obtaining the third SOC balance speed change value of each adjustment target battery in the active discharge balance mainly includes:

Acquiring a third real-time SOC estimated value of each regulated target battery after active discharge equalization;

Performing active discharge equalization on each adjustment target battery;

Acquiring a third change time period from a third real-time SOC estimated value to a preset SOC discharge balance value of each regulation target battery;

acquiring a plurality of third sampling time points according to the third change time period;

establishing a third SOC trend change map (as shown in fig. 5) for each adjustment target battery according to a plurality of the third sampling time points;

Acquiring a third slope change value of each adjustment target battery at a third sampling time point according to a third SOC trend change chart;

calculating according to a third slope change value corresponding to a third sampling time point to obtain a third SOC balance speed change value;

in one embodiment, the step of calculating the performance evaluation value of the adjustment target battery according to the first SOC balance speed variation value, the second SOC balance speed variation value, and the third SOC balance speed variation value includes:

S801, acquiring a first SOC balance speed change value of each adjustment target battery;

S802, acquiring a first weight value of a first SOC balance speed change value;

s803, obtaining a second SOC balance speed change value of each adjustment target battery;

s804, acquiring a second weight value of a second SOC balance speed change value;

S805, obtaining a third SOC balance speed change value of each adjustment target battery;

s806, obtaining a third weight value of a third SOC balance speed change value;

S807, calculating each single battery performance evaluation value according to the first SOC balance speed change value, the first weight value, the second SOC balance speed change value, the second weight value, the third SOC balance speed change value and the third weight value, wherein the calculation formula is as follows:

；

wherein P is an evaluation value of the performance of the single storage battery, a is a variation value of the passive equalization speed of the SOC, B is a first weight value, b is a first SOC active equalization speed variation value,C is a second weight value, c is a second SOC autonomous equalizing speed variation value,Is a third weight value.

As described in the above steps S801 to S807, by monitoring and calculating the first SOC balance speed change value of the adjustment target battery, which can represent the self-balancing ability of the adjustment target battery under the passive balance adjustment, thereby identifying those adjustment target batteries with poor self-balancing ability, which may be more likely to have performance degradation or malfunction, and then monitoring and calculating the second SOC balance speed change value of the adjustment target battery during the active charge equalization, by which the performance of the adjustment target battery during the charge, such as the charge speed, the charge efficiency, etc., can be represented, which may require more frequent maintenance or replacement, can be identified, monitoring and calculating a third SOC balance speed change value of the regulation target battery, wherein the third SOC balance speed change value reflects the performance of the regulation target battery in the discharging process, such as discharging speed, discharging efficiency and the like, the regulation target battery with poor performance in the discharging process can be identified, the regulation target battery can not provide enough energy or can fail in advance, the performance evaluation value of each regulation target battery is obtained through weighting calculation by combining the first SOC balance speed change value, the second SOC balance speed change value and the third SOC balance speed change value and corresponding weight values, a comprehensive, accurate and quantized performance evaluation result is provided, finally the performance problem of the regulation target battery can be timely found and solved through comprehensive evaluation of the performance of the regulation target battery, the reliability and the service life of the battery pack are improved.

The invention also provides a monitoring system of the storage battery, which comprises:

The first acquisition module 1 is used for acquiring real-time current data of each single storage battery in a floating state of the battery pack according to a discrete sampling method and acquiring a time interval of the real-time current data of each single storage battery;

a second obtaining module 2, configured to obtain a first real-time SOC estimation value according to the real-time current data and the time interval;

The first judging module 3 is configured to judge whether the first real-time SOC estimation value of each of the single batteries is in a preset interval, and take all the single batteries not in the preset interval as adjustment target batteries;

The adjusting module 4 is used for carrying out balance adjustment on the adjustment target battery, wherein the balance adjustment comprises passive balance adjustment, active charge balance and active discharge balance;

A third acquisition module 5 for acquiring a first SOC-equalization-speed variation value of each adjustment target battery in passive equalization adjustment;

a fourth acquisition module 6 for acquiring a second SOC balance speed change value of each adjustment target battery in the active charge balance;

A fifth acquisition module 7 for acquiring a third SOC balance speed change value of each adjustment target battery in the active discharge balance;

A calculation module 8 for calculating a performance evaluation value of the adjustment target battery according to the first SOC balance speed variation value, the second SOC balance speed variation value, and the third SOC balance speed variation value;

a second judging module 9 for judging whether the performance evaluation value is greater than a preset value;

And if at least one performance evaluation value of the adjustment target battery is larger than a preset value, performing on-line shallow charging and shallow discharging activation on the corresponding adjustment target battery larger than the preset value.

In one embodiment, the second obtaining module 2 includes:

A first obtaining unit, configured to obtain an initial preset SOC value of each unit battery;

The second acquisition unit is used for acquiring real-time current data of each single storage battery;

A third acquisition unit for acquiring a rated capacity value of each of the single batteries;

A fourth acquisition unit configured to acquire a sampling time interval of each unit battery, where the sampling time interval includes a start time point and an end time point;

a fifth acquisition unit configured to acquire a charge-discharge efficiency value of each of the battery cells:

The first calculating unit is used for calculating a first real-time SOC estimated value according to an initial preset SOC value, a rated capacity value, real-time current data, a time interval and a charge-discharge efficiency value, wherein a calculation formula is as follows:

；

wherein, For the first real-time SOC estimate value,For the initial preset SOC-value(s),As the value of the rated capacity,In order to obtain the charge-discharge efficiency value,For the real-time current data,In order to start the time point of the time interval,Is the time point at which the time interval ends.

In one embodiment, the adjustment module 4 comprises:

the first marking unit is used for taking the adjusting target battery which is larger than a preset interval as a first single battery;

a second marking unit, configured to take an adjustment target battery smaller than a preset interval as a second unit battery;

The first construction unit is used for constructing a first topological circuit for all the first single batteries;

The second construction unit is used for constructing a second topological circuit for all the second single batteries;

A sixth obtaining unit, configured to obtain a maximum preset value of the preset interval;

A seventh obtaining unit, configured to obtain a first difference between a first real-time SOC estimation value corresponding to each first unit cell and a maximum preset value;

The first adjusting unit is used for carrying out passive balance adjustment on the first single batteries and transmitting the electric energy corresponding to the first difference value of each first single battery to the energy storage element;

an eighth obtaining unit, configured to obtain a minimum preset value of a preset interval;

a ninth obtaining unit, configured to obtain a second difference value between the first real-time SOC estimation value corresponding to each second unit cell and a minimum preset value;

The second adjusting unit is used for transmitting the electric energy to the second topological circuit by the energy storage element and carrying out passive balanced adjustment on a second single battery corresponding to the second topological circuit based on a second difference value;

A tenth acquisition unit configured to acquire a preset SOC charge equalization value;

the third adjusting unit is used for actively equalizing charge of all the first single batteries and all the second single batteries based on the first preset SOC charge equalization value;

an eleventh acquisition unit for acquiring a preset SOC discharge equalization value;

And the fourth adjusting unit is used for actively discharging and balancing all the first single batteries and all the second single batteries based on a preset SOC discharging and balancing value.

Preferably, the calculation module 8 comprises:

a twelfth acquisition unit for acquiring a first SOC balance speed change value of each adjustment target battery;

a thirteenth acquisition unit configured to acquire a first weight value of the first SOC equalization speed variation value;

a fourteenth acquisition unit configured to acquire a second SOC-equalization-speed variation value for each adjustment target battery;

A fifteenth acquisition unit configured to acquire a second weight value of the second SOC equalization speed variation value;

A sixteenth acquisition unit configured to acquire a third SOC balance speed change value for each adjustment target battery;

A seventeenth obtaining unit, configured to obtain a third weight value of the third SOC equalization speed variation value;

A second calculating unit, configured to calculate each single battery performance evaluation value according to the first SOC equalization speed variation value, the first weight value, the second SOC equalization speed variation value, the second weight value, the third SOC equalization speed variation value, and the third weight value, where the calculation formula is:

；

wherein P is an evaluation value of the performance of the single storage battery, a is a variation value of the passive equalization speed of the SOC, B is a first weight value, b is a first SOC active equalization speed variation value,C is a second weight value, c is a second SOC autonomous equalizing speed variation value,Is a third weight value.

Those skilled in the art will appreciate that implementing all or part of the above described methods may be accomplished by way of a computer program stored on a non-transitory computer readable storage medium, which when executed, may comprise the steps of the embodiments of the methods described above. Any reference to memory, storage, database, or other medium provided by the present application and used in embodiments may include non-volatile and/or volatile memory. The nonvolatile memory can include Read Only Memory (ROM), programmable ROM (PROM), electrically Programmable ROM (EPROM), electrically Erasable Programmable ROM (EEPROM), or flash memory. Volatile memory can include Random Access Memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in a variety of forms such as Static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), dual speed data rate SDRAM (SSRSDRAM), enhanced SDRAM (ESDRAM), synchronous link (SYNCHLINK) DRAM (SLDRAM), memory bus (Rambus) direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM), among others.

It should be noted that, in this document, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, apparatus, article, or method that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, apparatus, article, or method. Without further limitation, an element defined by the phrase "comprising one … …" does not exclude the presence of other like elements in a process, apparatus, article, or method that comprises the element.

The foregoing description is only of the preferred embodiments of the present invention and is not intended to limit the scope of the invention, and all equivalent structures or equivalent processes using the descriptions and drawings of the present invention or directly or indirectly applied to other related technical fields are included in the scope of the invention.

Claims (3)

1. A method of monitoring a battery, comprising:

acquiring real-time current data of each single storage battery of the battery pack in a floating state according to a discrete sampling method, and acquiring a time interval of the real-time current data of each single storage battery;

Acquiring a first real-time SOC estimated value according to the real-time current data and the time interval;

Judging whether the first real-time SOC estimation value of each single storage battery is in a preset interval or not, and taking all the single storage batteries corresponding to the first real-time SOC estimation values which are not in the preset interval as adjustment target batteries;

Performing balance adjustment on an adjustment target battery, wherein the balance adjustment comprises passive balance adjustment, active charge balance and active discharge balance;

acquiring a first SOC balance speed change value of each regulation target battery in passive balance regulation;

acquiring a second SOC balance speed change value of each adjustment target battery in active charge balance;

acquiring a third SOC balance speed change value of each adjustment target battery in active discharge balance;

calculating a performance evaluation value of the adjustment target battery according to the first SOC balance speed change value, the second SOC balance speed change value and the third SOC balance speed change value;

judging whether the performance evaluation value is larger than a preset value or not;

If at least one performance evaluation value of the adjusting target battery is larger than a preset value, performing on-line shallow charging and shallow discharging activation on the corresponding adjusting target battery larger than the preset value;

The step of obtaining a first real-time SOC estimation value according to the real-time current data and the time interval includes:

acquiring an initial preset SOC value of each single storage battery;

acquiring real-time current data of each single storage battery;

acquiring the rated capacity value of each single storage battery;

Acquiring a sampling time interval of each single storage battery, wherein the sampling time interval comprises a starting time point and an ending time point;

acquiring a charge and discharge efficiency value of each single storage battery;

Calculating a first real-time SOC estimation value according to an initial preset SOC value, an rated capacity value, real-time current data, a time interval and a charge and discharge efficiency value, wherein a calculation formula is as follows:

the Soc _k is a first real-time Soc estimation value of the kth single storage battery, SOc _m is an initial preset Soc value, Q _k is a rated capacity value of the kth single storage battery, η _k is a charge and discharge efficiency value of the kth single storage battery, i _k is real-time current data of the kth single storage battery, t _h-1 is a sampling time interval starting time point, and t _h is a sampling time interval ending time point;

the step of performing balanced adjustment on the program label battery comprises the following steps:

taking an adjusting target battery larger than a preset interval as a first single battery;

taking the regulation target battery smaller than the preset interval as a second single battery;

Constructing a first topological circuit for all the first single batteries;

constructing a second topological circuit for all the second single batteries;

Obtaining a maximum preset value of a preset interval;

Acquiring a first difference value between a first real-time SOC estimated value corresponding to each first single battery and a maximum preset value;

carrying out passive balance adjustment on the first single batteries, and transmitting the electric energy corresponding to the first difference value of each first single battery to the energy storage element;

Acquiring a minimum preset value of a preset interval;

Acquiring a second difference value between a first real-time SOC estimated value corresponding to each second single battery and a minimum preset value;

the energy storage element transmits electric energy to the second topological circuit, and performs passive equalization adjustment on a second single battery corresponding to the second topological circuit based on a second difference value;

acquiring a preset SOC charge balance value;

Performing active charge equalization on all the first single batteries and all the second single batteries based on a first preset SOC charge equalization value;

Acquiring a preset SOC discharge balance value;

performing active discharge equalization on all the first single batteries and all the second single batteries based on a preset SOC discharge equalization value;

Wherein the step of obtaining the first SOC balance speed change value of each adjustment target battery in the passive balance adjustment includes:

acquiring a first change time period of passive equalization adjustment of each adjustment target battery;

acquiring a plurality of first sampling time points according to a first change time period;

establishing a first SOC trend change chart of each regulation target battery according to a plurality of first sampling time points;

acquiring a first slope change value of each adjustment target battery at a first sampling time point according to a first SOC trend change chart;

Calculating according to the corresponding first slope change values of all the first sampling time points to obtain a first SOC balance speed change value;

the step of calculating the performance evaluation value of the adjustment target battery according to the first SOC balance speed change value, the second SOC balance speed change value and the third SOC balance speed change value includes:

acquiring a first SOC balance speed change value of each regulation target battery;

acquiring a first weight value of a first SOC balance speed change value;

Acquiring a second SOC balance speed change value of each regulation target battery;

acquiring a second weight value of a second SOC balance speed change value;

acquiring a third SOC balance speed change value of each regulation target battery;

Acquiring a third weight value of a third SOC balance speed change value;

calculating the performance evaluation value of each single storage battery according to the first SOC balance speed change value, the first weight value, the second SOC balance speed change value, the second weight value, the third SOC balance speed change value and the third weight value, wherein the calculation formula is as follows:

P＝a*L₁+b*L₂+c*L₃；

Wherein, P is an evaluation value of the performance of the single battery, a is a variation value of the passive equalization speed of the SOC, L ₁ is a first weight value, b is a variation value of the active equalization speed of the first SOC, L ₂ is a second weight value, c is a variation value of the autonomous equalization speed of the second SOC, and L ₃ is a third weight value.

2. The battery monitoring method according to claim 1, wherein the step of acquiring the second SOC balance speed change value of each adjustment target battery in the active charge balance includes:

acquiring a second real-time SOC estimated value of each adjusted target battery after passive equalization adjustment;

performing active charge equalization on each regulation target battery;

Acquiring a second change time period from a second real-time SOC estimated value to a preset SOC charge balance value of each regulation target battery;

Acquiring a plurality of second sampling time points according to the second change time period;

Establishing a second SOC trend change map of each regulation target battery according to a plurality of second sampling time points;

Acquiring a second slope change value of each adjustment target battery at a second sampling time point according to a second SOC trend change chart;

and calculating according to the second slope change value corresponding to the second sampling time point to obtain a second SOC balance speed change value.

3. A monitoring system for a battery, comprising:

the first acquisition module is used for acquiring real-time current data of each single storage battery in a floating state of the battery pack according to a discrete sampling method and acquiring a time interval of the real-time current data of each single storage battery;

The second acquisition module is used for acquiring a first real-time SOC estimated value according to the real-time current data and the time interval;

the first judging module is used for judging whether the first real-time SOC estimated value of each single storage battery is in a preset interval or not, and taking all the single storage batteries which are not in the preset interval as adjustment target batteries;

The adjusting module is used for carrying out balance adjustment on the adjustment target battery, wherein the balance adjustment comprises passive balance adjustment, active charge balance and active discharge balance;

a third acquisition module for acquiring a first SOC balance speed change value of each adjustment target battery in passive balance adjustment;

a fourth acquisition module for acquiring a second SOC equalization speed variation value of each adjustment target battery in the active charge equalization;

A fifth acquisition module for acquiring a third SOC equalization speed variation value of each adjustment target battery in the active discharge equalization;

The calculation module is used for calculating a performance evaluation value of the adjustment target battery according to the first SOC balance speed change value, the second SOC balance speed change value and the third SOC balance speed change value;

The second judging module is used for judging whether the performance evaluation value is larger than a preset value or not;

If at least one performance evaluation value of the adjusting target battery is larger than a preset value, performing on-line shallow charging and shallow discharging activation on the corresponding adjusting target battery larger than the preset value;

The step of obtaining a first real-time SOC estimation value according to the real-time current data and the time interval includes:

acquiring an initial preset SOC value of each single storage battery;

acquiring real-time current data of each single storage battery;

acquiring the rated capacity value of each single storage battery;

Acquiring a sampling time interval of each single storage battery, wherein the sampling time interval comprises a starting time point and an ending time point;

acquiring a charge and discharge efficiency value of each single storage battery;

Calculating a first real-time SOC estimation value according to an initial preset SOC value, an rated capacity value, real-time current data, a time interval and a charge and discharge efficiency value, wherein a calculation formula is as follows:

The Soc _k is a first real-time Soc estimation value of the kth single battery, soc _m is an initial preset Soc value, Q _k is a rated capacity value of the kth single battery, η _k is a charge-discharge efficiency value of the kth single battery, i _k is real-time current data of the kth single battery, t _h-1 is a sampling time interval start time point, and t _h is a sampling time interval end time point;

the step of performing balanced adjustment on the program label battery comprises the following steps:

taking an adjusting target battery larger than a preset interval as a first single battery;

taking the regulation target battery smaller than the preset interval as a second single battery;

Constructing a first topological circuit for all the first single batteries;

constructing a second topological circuit for all the second single batteries;

Obtaining a maximum preset value of a preset interval;

Acquiring a first difference value between a first real-time SOC estimated value corresponding to each first single battery and a maximum preset value;

carrying out passive balance adjustment on the first single batteries, and transmitting the electric energy corresponding to the first difference value of each first single battery to the energy storage element;

Acquiring a minimum preset value of a preset interval;

Acquiring a second difference value between a first real-time SOC estimated value corresponding to each second single battery and a minimum preset value;

the energy storage element transmits electric energy to the second topological circuit, and performs passive equalization adjustment on a second single battery corresponding to the second topological circuit based on a second difference value;

acquiring a preset SOC charge balance value;

Performing active charge equalization on all the first single batteries and all the second single batteries based on a first preset SOC charge equalization value;

Acquiring a preset SOC discharge balance value;

performing active discharge equalization on all the first single batteries and all the second single batteries based on a preset SOC discharge equalization value;

Wherein the step of obtaining the first SOC balance speed change value of each adjustment target battery in the passive balance adjustment includes:

acquiring a first change time period of passive equalization adjustment of each adjustment target battery;

acquiring a plurality of first sampling time points according to a first change time period;

establishing a first SOC trend change chart of each regulation target battery according to a plurality of first sampling time points;

acquiring a first slope change value of each adjustment target battery at a first sampling time point according to a first SOC trend change chart;

Calculating according to the corresponding first slope change values of all the first sampling time points to obtain a first SOC balance speed change value;

the step of calculating the performance evaluation value of the adjustment target battery according to the first SOC balance speed change value, the second SOC balance speed change value and the third SOC balance speed change value includes:

acquiring a first SOC balance speed change value of each regulation target battery;

acquiring a first weight value of a first SOC balance speed change value;

Acquiring a second SOC balance speed change value of each regulation target battery;

acquiring a second weight value of a second SOC balance speed change value;

acquiring a third SOC balance speed change value of each regulation target battery;

Acquiring a third weight value of a third SOC balance speed change value;

calculating the performance evaluation value of each single storage battery according to the first SOC balance speed change value, the first weight value, the second SOC balance speed change value, the second weight value, the third SOC balance speed change value and the third weight value, wherein the calculation formula is as follows:

P＝a*L₁+b*L₂+c*L₃；

Wherein, P is an evaluation value of the performance of the single battery, a is a variation value of the passive equalization speed of the SOC, L ₁ is a first weight value, b is a variation value of the active equalization speed of the first SOC, L ₂ is a second weight value, c is a variation value of the autonomous equalization speed of the second SOC, and L ₃ is a third weight value.