Battery on-line monitoring and intelligent capacity verification device

Abstract

The present invention discloses an on-line monitoring and intelligent capacity calibration device for storage batteries, which relates to the technical field of intelligent capacity calibration and is used to solve the problems of inaccurate battery management, poor adaptability, and non-refined attenuation process in the prior art; the three-level correction is simplified to two-level, which not only retains the consideration of the main influencing factors but also simplifies the calculation process. For some situations where the accuracy requirement is not extremely high, the primary and secondary corrections can still make a relatively reasonable adjustment to the end voltage without excessively increasing the calculation complexity. By making full use of the data of the built-in sensors and the historical usage data of the battery, the correction decision can be based on evidence, improving the reliability and accuracy of the entire system. Selecting different functions according to the actual situation helps to optimize the voltage attenuation processing in the entire on-line capacity calibration process, improving the overall performance and efficiency of the system while ensuring accuracy.

Description

Technical Field

[0001] The present invention relates to the technical field of intelligent capacity verification, and more specifically, to an on-line monitoring and intelligent capacity verification device for storage batteries. Background Art

[0002] With the continuous growth of energy demand and the dependence of power systems on energy storage devices, storage batteries, especially large-scale energy storage batteries, are becoming more and more widely used in power systems. The emergence of on-line monitoring and intelligent capacity verification technologies for storage batteries aims to real-time master the health status, capacity attenuation and service life of storage batteries, so as to improve the reliability and economy of the system. The performance of storage batteries is affected by various factors, including the type of battery, the use environment, charge and discharge conditions, temperature, humidity, and battery aging. Therefore, real-time monitoring of storage batteries becomes crucial.

[0003] The existing technologies have the following deficiencies:

[0004] The battery management system in the existing technologies may have inaccurate setting of the termination voltage, resulting in over-discharge or over-charge of the battery, affecting the life and safety of the battery. By real-time monitoring the built-in temperature sensor and discharge current, combined with on-line capacity verification, it is possible to dynamically judge whether the original termination voltage of the battery is reasonable. The traditional battery discharge process may use a fixed attenuation function, but in practice, the discharge characteristics of the battery are often non-linear. There are problems in the existing technologies such as inaccurate battery management, poor adaptability, and non-precise attenuation process.

[0005] In view of the above problems, the present invention proposes a solution. Summary of the Invention

[0006] In order to overcome the above defects of the existing technologies, embodiments of the present invention provide an on-line monitoring and intelligent capacity verification device for storage batteries to solve the problems proposed in the above background art.

[0007] To achieve the above object, the present invention provides the following technical solutions:

[0008] An on-line monitoring and intelligent capacity verification device for storage batteries, including: a correction classification module, a judgment and correction module, a selected function module, and an attenuation processing module, with signal connections between the modules:

[0009] Correction classification module: Add a PTC resistor load as a load correction, combine aging correction and temperature compensation to correct the original termination voltage of the storage battery as a three-level correction, and simplify the three-level correction as a first-level correction and a second-level correction;

[0010] Judgment and correction module: Obtain the temperature data of the built-in temperature sensor, and judge whether the original termination voltage of the online capacitance calibration is reasonable based on the discharge current. If it is unreasonable, three-level correction is used. If it is reasonable, the correction level is comprehensively judged in combination with the charge state consistency and capacity attenuation of the battery, and the original termination voltage is corrected to the corrected termination voltage;

[0011] Selected function module: Determine whether to select an exponential decay function or a linear decay function as the selected decay function based on the accuracy requirements during the discharge process and whether the original termination voltage is reasonable;

[0012] Attenuation processing module: Use the selected decay function and the corrected termination voltage to process the voltage attenuation process of the online capacitance calibration.

[0013] In a preferred embodiment, the correction grading module includes the following:

[0014] Load correction: Add a PTC resistor load for correction. Select a PTC resistor with an appropriate rated power and initial resistance value, connect the PTC resistor in series in the discharge circuit of the storage battery, and denote the PTC resistor as , denote the discharge current of the storage battery as I, and the load correction of the PTC resistor is expressed as: =I× , where I is the discharge current of the storage battery, is the PTC resistor;

[0015] Temperature compensation correction: Record the operating environment temperature of the storage battery measured by the temperature sensor as T, obtain the temperature-voltage characteristic curve of the storage battery, and obtain the current standard temperature based on the curve , then the temperature deviation , and the temperature compensation correction is expressed as: , where α is determined by different types of batteries;

[0016] Aging correction: Record the charge and discharge cycle times of the storage battery as n, record the voltage correction value corresponding to the internal resistance increase of x% for each increase, , the internal resistance increases by z% every y cycles, calculate the internal resistance increase ratio p = ny×z%, and the voltage correction value caused by the internal resistance increase is expressed as: =p× , assume the internal resistance increase is ΔR, determine the relationship coefficient k between the internal resistance increase and the voltage correction value according to the aging model of different types of storage batteries, and the voltage correction value caused by the internal resistance increase is expressed as: =k×ΔR, then the final aging correction value is expressed as: + ;

[0017] The original termination voltage is , and the temperature compensation correction value calculated above , Aging correction value and the PTC resistor load correction value are added together to obtain the corrected termination voltage ;

[0018] The importance ranking of the three correction measures is: temperature compensation > aging correction > PTC resistor load. Adding the PTC resistor load is used as the load correction. Combining the aging correction and temperature compensation to correct the original termination voltage of the battery is used as the three - level correction. According to the importance of the three correction measures, only using the aging correction and temperature compensation to correct the original termination voltage of the battery is used as the two - level correction. The corrected termination voltage is expressed as: , only using temperature compensation to correct the original termination voltage of the battery is used as the one - level correction. The corrected termination voltage is expressed as: .

[0019] In a preferred embodiment, the judgment correction module includes the following:

[0020] Record the working environment temperature of the battery measured by the temperature sensor as T, record the discharge current of the battery as I, establish a temperature - discharge current - termination voltage relationship model, substitute the obtained temperature T and discharge current I into the reference model, and calculate the theoretically reasonable termination voltage range to , and at the same time obtain the actual termination voltage during the current online capacity verification process , when or , it is determined that the original termination voltage is unreasonable and three - level correction is required. When , it is determined that the original termination voltage is reasonable, and then the correction level is further judged;

[0021] Judge the charging state consistency: Obtain the battery charging history record, and count the number of times the charging voltage exceeds the target charging voltage and the number of times below the lower limit of the target charging voltage , when + = 0, it is considered that the charging state consistency is good; when + ≤2, it is considered that the charging state is relatively consistent; if + >2, it is considered that the charging state is inconsistent.

[0022] Let the total number of charging cycles be N. When + = 0, S = 0; when + ≤2, S = ×0.5; when + When >2, S = (The value range of S is 0−1);

[0023] Judgment of capacity attenuation: According to the rated capacity of the battery and the actual capacity Q measured recently, calculate the capacity retention rate C = , when C≥90%, it is defined as mild attenuation; when 80%≤C<90%, it is defined as moderate attenuation; if C<80%, it is defined as severe attenuation;

[0024] When C≥90%, D = 0; when 80%≤C<90%, D=(90%−C)×10; when C<80%, D=(90%−C)×20, (The value range of D is 0−20);

[0025] Combined with the charging state consistency and capacity attenuation of the battery, comprehensively judge the correction level:

[0026] 1. First-level correction: When S = 0 and D = 0, only temperature compensation correction is required, and the correction level is the first level;

[0027] 2. Second-level correction: When S<=0.3 and D<=10, in addition to temperature compensation, consider capacity attenuation for correction, and the correction level is the second level;

[0028] 3. Third-level correction: When S>0.3 or D>10, comprehensively consider the charging state, capacity attenuation and temperature compensation for correction, and the correction level is the third level.

[0029] In a preferred embodiment, the selected function module includes the following content:

[0030] Obtain the historical operation data of the battery system that has been put into use, analyze the historical data, obtain the accuracy requirements of the discharge process, and set a threshold to judge the level of the accuracy requirements of the discharge process;

[0031] After the selected function module receives the accuracy requirements of the discharge process and whether the original termination voltage is reasonable, define the accuracy requirements of the discharge process and whether the original termination voltage is reasonable as input variables, and divide them into different fuzzy sets respectively;

[0032] Define the selected attenuation function as the output variable and divide it into a fuzzy set;

[0033] Formulate fuzzy rules to describe the influence of the accuracy requirements of the discharge process and whether the original termination voltage is reasonable on the selected attenuation function;

[0034] Perform fuzzy reasoning according to the fuzzy rules to determine the selected attenuation function.

[0035] In a preferred embodiment, the attenuation processing module includes the following:

[0036] The exponential decay function is expressed as: , where: is the voltage at time t, is the initial voltage, τ is the time constant, e is the base of the natural logarithm. According to the exponential decay function, the voltage decays exponentially starting from . When the corrected termination voltage is reached, the system stops discharging in a timely manner, monitors the voltage in real time, and compares it with the corrected termination voltage. Once the monitored voltage is less than or equal to the corrected termination voltage, the mechanism to stop discharging is immediately triggered;

[0037] The linear decay function is expressed as: , where V(t) is the voltage at time t, is the initial voltage, k is the decay constant, which determines the amplitude of the voltage drop per unit time. According to the linear decay function, the voltage decays exponentially starting from . When the corrected termination voltage is reached, the system stops discharging in a timely manner. Similarly, the voltage is monitored in real time and compared with the corrected termination voltage. Once the monitored voltage is less than or equal to the corrected termination voltage, the mechanism to stop discharging is immediately triggered.

[0038] Technical effects and advantages of the battery online monitoring and intelligent capacity verification device of the present invention:

[0039] The three-level correction is simplified to a two-level one, which not only retains the consideration of the main influencing factors but also simplifies the calculation process. For some situations where extremely high precision is not required, the primary and secondary corrections can still make a relatively reasonable adjustment to the termination voltage without overly increasing the computational complexity. By fully utilizing the data from the built-in sensors and the historical usage data of the battery, the correction decision is well-founded, improving the reliability and accuracy of the entire system. Selecting different functions according to the actual situation helps to optimize the voltage attenuation processing during the entire online capacity verification process, improving the overall performance and efficiency of the system while ensuring accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 is a schematic structural diagram of the battery online monitoring and intelligent capacity verification device of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0041] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0042] Embodiment 1

[0043] As shown in the present invention Figure 1 a battery online monitoring and intelligent capacity calibration device is disclosed, including: a correction classification module, a judgment and correction module, a selected function module, and an attenuation processing module, and the signals of each module are connected.

[0044] Correction classification module: Add a PTC resistor load for load correction, and combine aging correction and temperature compensation to correct the original cut-off voltage of the battery as a three-level correction, and simplify the three-level correction as a first-level correction and a second-level correction;

[0045] Judgment and correction module: Obtain the temperature data of the built-in temperature sensor and the discharge current to judge whether the original cut-off voltage of the online capacity calibration is reasonable. If it is unreasonable, use the three-level correction. If it is reasonable, comprehensively judge the correction level in combination with the charging state consistency and capacity attenuation of the battery, and correct the original cut-off voltage to the corrected cut-off voltage;

[0046] Selected function module: Decide whether to select an exponential decay function or a linear decay function as the selected decay function in combination with the accuracy requirements of the discharge process and whether the original cut-off voltage is reasonable;

[0047] Attenuation processing module: Use the selected decay function and the corrected cut-off voltage to process the voltage decay process of the online capacity calibration.

[0048] The functions of each module are as follows:

[0049] In the information acquisition module, add a PTC resistor load for load correction, and combine aging correction and temperature compensation to correct the original cut-off voltage of the battery as a three-level correction, and simplify the three-level correction as a first-level correction and a second-level correction. The specific content includes:

[0050] Load correction:

[0051] Adding a PTC resistor load for correction is mainly used to smooth the voltage drop curve and flexibly adjust the cut-off voltage threshold. In some specific application scenarios, such as when rapid response to voltage changes or adjustment of discharge characteristics is required, the PTC resistor load can play a key role. However, in conventional applications, temperature compensation and aging correction are often more basic and generally applicable, while the PTC resistor load can be selectively added according to specific needs.

[0052] According to the rated voltage, rated current of the storage battery and the expected load correction range, select a PTC resistor with appropriate rated power and initial resistance value, and connect the PTC resistor in series in the discharge circuit of the storage battery.

[0053] According to Ohm's law, the load correction of the PTC resistor is expressed as: =I× , where I is the discharge current of the storage battery, is the PTC resistor. During the discharge process, as time goes by, will increase, increases, also increases accordingly.

[0054] Temperature compensation correction:

[0055] Temperature has a significant impact on the performance of the storage battery. Temperature changes will directly cause changes in the internal resistance and voltage of the storage battery. In practical applications, the storage battery often faces working conditions in different temperature environments. Therefore, temperature compensation is crucial for ensuring the accuracy of the termination voltage. Accurate temperature compensation can reduce misjudgment caused by environmental temperature fluctuations and improve the stability and reliability of the storage battery system.

[0056] Use a temperature sensor to accurately measure the working environment temperature T of the storage battery. The measurement accuracy can be based on actual requirements. According to the type of the storage battery (such as lead-acid battery, lithium-ion battery, etc.), obtain its existing temperature-voltage characteristic curve, and obtain the current standard temperature . The temperature-voltage characteristic curve is obtained through a large number of experimental tests and reflects the change law of the open-circuit voltage or terminal voltage of the storage battery at different temperatures.

[0057] The measured temperature is T, and the standard temperature is , then the temperature deviation ΔT = T − . The temperature compensation correction is expressed as: , where α is determined by different types of batteries and will not be elaborated here. If ΔT is positive, the temperature is higher than the standard temperature, then is positive; if ΔT is negative, the temperature is lower than the standard temperature, then is negative. For example, for a lead-acid battery, in a low-temperature environment, its voltage will drop significantly, about 3 - 5 mV for every 10 °C drop. Assuming an average value of 4 mV is taken, then the temperature compensation correction is: = ×ΔT. If the temperature is higher than the standard temperature, then is positive; if the temperature is lower than the standard temperature, then is negative.

[0058] Aging correction:

[0059] As the battery ages over time, it exhibits characteristics such as increased internal resistance and decreased capacity. Adjust the termination voltage threshold according to the actual usage of the battery to reflect its current performance state. Although aging is a gradual process, it will have a significant impact on the battery's performance over the long term. Therefore, aging correction is also an essential part.

[0060] Charge and discharge cycle count: Accurately record the charge and discharge cycle count n of the battery. Generally, after a certain number of charge and discharge cycles (e.g., every 100 cycles for lead-acid batteries), the performance of the battery will significantly decline.

[0061] Let the charge and discharge cycle count be n. For every x% increase in internal resistance, there is a corresponding voltage correction value , and for every y cycles, the internal resistance increases by z%. Calculate the internal resistance increase ratio p = ny×z%. The voltage correction value due to the increase in internal resistance = p× .

[0062] Let the increase in internal resistance be ΔR. Determine the relationship coefficient k between the increase in internal resistance and the voltage correction value according to the aging model of different types of batteries. The voltage correction value due to the increase in internal resistance = k×ΔR.

[0063] Considering both the cycle count and internal resistance measurement methods, the final aging correction value is expressed as: + .

[0064] Taking a lithium-ion battery as an example, for illustration: Let the voltage correction value corresponding to a 10% increase in internal resistance be = 2.5 mV, and the internal resistance increases by 10% every 100 cycles. The charge and discharge cycle count is n.

[0065] First, calculate the internal resistance increase ratio p = ×10% = . The voltage correction value due to the increase in internal resistance = p× = ×2.5 = mV. Let the increase in internal resistance be ΔR. For a lithium-ion battery, let the relationship coefficient k = 0.25 mV / mΩ. The voltage correction value due to the increase in internal resistance = k×ΔR == 0.25×ΔR mV. The final aging correction value is expressed as and .

[0066] The original termination voltage is known as , and the temperature compensation correction value calculated above and the aging correction value are added to the PTC resistor load correction value to obtain the corrected termination voltage .

[0067] To sum up, from a general perspective, the importance ranking of these three correction measures is: temperature compensation > aging correction > PTC resistor load.

[0068] Therefore, adding a PTC resistor load is used as the load correction, and combining the aging correction and temperature compensation to correct the original termination voltage of the battery as the three - level correction. According to the importance of the three correction measures, only using the aging correction and temperature compensation to correct the original termination voltage of the battery is used as the two - level correction. The corrected termination voltage is expressed as: , and only using temperature compensation to correct the original termination voltage of the battery is used as the one - level correction. The corrected termination voltage is expressed as: .

[0069] In the judgment correction module, the temperature data of the built - in temperature sensor is obtained, and the discharge current is used to judge whether the original termination voltage of the online capacity verification is reasonable. If it is not reasonable, the three - level correction is used. If it is reasonable, the correction level is comprehensively judged in combination with the charging state consistency and capacity attenuation of the battery, and the original termination voltage is corrected to the corrected termination voltage. The specific content includes:

[0070] The working environment temperature T of the battery is accurately measured using a temperature sensor, and the measurement accuracy can be set to ±0.5°C. The real - time discharge current I of the battery during the discharge process is measured using a current sensor.

[0071] According to the type of the battery, a relationship model of temperature - discharge current - termination voltage is established, which can be obtained through a large amount of experimental data and theoretical analysis. For example, for lead - acid batteries, within a certain discharge current range, when the temperature changes by 10°C, the termination voltage will have a certain fluctuation range (such as when the temperature drops by 10°C, the terminal voltage may drop by 3 - 5 mV).

[0072] The obtained temperature T and discharge current I are substituted into the reference model to calculate the theoretically reasonable termination voltage range to , and at the same time, the actual termination voltage during the current online capacity verification process is obtained . If or , it is determined that the original termination voltage is unreasonable and three - level correction is required. When , it is determined that the original termination voltage is reasonable, and then the correction level is further judged.

[0073] Judgment on the consistency of charging status: Obtain the battery charging history record, and count the number of times the charging voltage exceeds the target charging voltage and the number of times it is lower than the lower limit of the target charging voltage in the recent charging cycles. and the number of times lower than the lower limit of the target charging voltage , when + = 0, it is considered that the charging status is good; when + ≤ 2, it is considered that the charging status is relatively consistent; if + > 2, it is considered that the charging status is inconsistent.

[0074] Let the total number of charging cycles be N. When + = 0, S = 0; when + ≤ 2, S = × 0.5; when + > 2, S = (the value range of S is 0 - 1).

[0075] Judgment on capacity attenuation: According to the rated capacity of the battery and the actual capacity Q measured recently, calculate the capacity retention rate C = . When C ≥ 90%, it is defined as mild attenuation; when 80% ≤ C < 90%, it is defined as moderate attenuation; if C < 80%, it is defined as severe attenuation.

[0076] When C ≥ 90%, D = 0; when 80% ≤ C < 90%, D = (90% - C) × 10; when C < 80%, D = (90% - C) × 20, (the value range of D is 0 - 20).

[0077] Comprehensively judge and correct the level by combining the charging status consistency and capacity attenuation of the battery:

[0078] 1. First-level correction (simple case)

[0079] When S = 0 and D = 0, only temperature compensation correction is required, and the correction level is the first level.

[0080] 2. Second-level correction (general case)

[0081] When S <= 0.3 and D <= 10, in addition to temperature compensation, capacity attenuation is considered for correction, and the correction level is the second level.

[0082] 3. Third-level correction (complex case)

[0083] When S > 0.3 or D > 10, corrections are made by comprehensively considering the state of charge, capacity fade, and temperature compensation, and the correction level is level three.

[0084] For example: For a certain battery with N = 10 charging cycles, = 1, = 0, then S = ×0.5 = 0.05; when its capacity retention rate C = 85%, then D = (90% - 85%) × 10 = 5. In this case, it may be necessary to consider capacity fade for a level-two correction.

[0085] In the selected function module, based on the accuracy requirements during the discharge process and whether the original termination voltage is reasonable, decide whether to choose an exponential decay function or a linear decay function as the selected decay function. The specific content includes:

[0086] For a battery system that has been put into use, obtain historical operation data, including voltage and current records during the discharge process and subsequent performance changes of the battery. By analyzing these data, the accuracy requirements during the discharge process can be inferred. If in some discharge processes, due to insufficient accuracy, the battery shows obvious performance degradation or failures, determine the accuracy level that needs to be achieved in these cases, and set a threshold to judge the high or low accuracy requirements of the discharge process.

[0087] After the selected function module receives the accuracy requirements during the discharge process and whether the original termination voltage is reasonable, define the accuracy requirements during the discharge process and whether the original termination voltage is reasonable as input variables, and divide them into different fuzzy sets.

[0088] For example, "Low", "Medium", "High" for the accuracy requirements during the discharge process, and "Yes", "No" for whether the original termination voltage is reasonable.

[0089] Define the selected decay function as the output variable and divide it into a fuzzy set. For example, "Index", "Linear" for the selected decay function.

[0090] Formulate a set of fuzzy rules to describe the influence of different input variables on the output variable. The definition of the rules can be based on professional knowledge or obtained through data analysis and experiments. For example:

[0091] Mark the accuracy requirements during the discharge process as A, whether the original termination voltage is reasonable as P, and the selected decay function as Decay Function, then it can be defined as

[0092] Rule 1: IF (A is High) AND (P is Yes) THEN (Decay Function is Index)

[0093] Rule 2: IF (A is Low) AND (P is No) THEN (Decay Function is Linear)

[0094] According to the fuzzy rules, perform fuzzy inference to determine the scheme for selecting the decay function.

[0095] It should be noted that the division of the fuzzy set can be adjusted according to the actual situation. For example, although three fuzzy sets are taken as an example in this embodiment, in fact, the accuracy requirements of the discharge process, whether the original termination voltage is reasonable, and the selected decay function can be divided into more than three sets to facilitate more accurate adjustment according to different temperatures.

[0096] Furthermore, for the judgment of the high, medium, and low accuracy requirements of the discharge process and whether the original termination voltage is reasonable, thresholds can be set according to the actual situation for judgment, which will not be elaborated here.

[0097] In the attenuation processing module, use the selected decay function and the corrected termination voltage to process the voltage attenuation process of on-line capacity verification. The specific content includes:

[0098] The expression form of the exponential decay function is: , where: is the voltage at time t, is the initial voltage, τ is the time constant, which determines the decay speed, and e is the base of the natural logarithm. According to the exponential decay function, let the voltage start from for exponential decay. When the corrected termination voltage is reached, the system stops discharging in time, and the voltage is monitored in real time and compared with the corrected termination voltage. Once the monitored voltage is less than or equal to the corrected termination voltage, the mechanism to stop discharging is immediately triggered.

[0099] It should be noted that the time constant τ is set by those skilled in the art according to the actual situation, which will not be elaborated here. The characteristic of the exponential decay function is that the voltage decreases exponentially with time, with a relatively fast decrease in the initial stage and a gradual flattening in the later stage, which is more in line with the non-linear characteristics in the actual battery discharge process and can better simulate the behavior of the battery at the initial stage of discharge and when approaching the termination voltage.

[0100] The expression form of the linear decay function is: , where: V(t) is the voltage at time t, is the initial voltage, and k is the decay constant, which determines the amplitude of the voltage drop per unit time. According to the linear decay function, let the voltage start from for exponential decay. When the corrected termination voltage is reached, the system stops discharging in time, and the voltage is also monitored in real time and compared with the corrected termination voltage. Once the monitored voltage is less than or equal to the corrected termination voltage, the mechanism for stopping discharge is immediately triggered.

[0101] It should be noted that the attenuation constant k is set by those skilled in the art according to the actual situation and will not be elaborated here. The characteristic of the linear attenuation function is that the voltage decreases linearly with time, and the decrease amplitude in each time period is the same. It is simple to calculate and easy to implement, but it may not be accurate enough in some cases, especially at the initial stage of discharge and when approaching the termination voltage.

[0102] The above formulas are all dimensionless and take their numerical values for calculation. The formula is obtained by collecting a large amount of data for software simulation to get a formula closest to the actual situation. The preset parameters in the formula are set by those skilled in the art according to the actual situation.

[0103] The above embodiments can be implemented in whole or in part by software, hardware, firmware, or any other combination. When implemented using software, the above embodiments can be implemented in whole or in part in the form of a computer program product.

[0104] Those of ordinary skill in the art can realize that the modules and algorithm steps of each example described in combination with the embodiments disclosed in this article can be implemented by electronic hardware, or by a combination of computer software and electronic hardware. Whether these functions are executed in a hardware or software manner depends on the specific application of the technical solution and the invention constraints. Professional technicians can use different methods to implement the described functions for each specific application, but such implementation should not be considered to exceed the scope of this application.

[0105] In addition, in each embodiment of this application, the functional modules can be integrated into one processing module, or each module can exist physically alone, or two or more modules can be integrated into one module.

[0106] The above is only the specific implementation manner of this application, but the protection scope of this application is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed in this application, and all should be covered by the protection scope of this application. Therefore, the protection scope of this application should be subject to the protection scope of the claims.

[0107] Finally: The above is only the preferred embodiment of the present invention and is not used to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. An on-line monitoring and intelligent capacity verification device for a storage battery, characterized in that, Including: A correction grading module, a judgment correction module, a selection function module, and an attenuation processing module, with signal connections between the modules; Correction grading module: Add a PTC resistor load as a load correction, combine the aging correction and temperature compensation to correct the original end voltage of the battery as a three-level correction, and simplify the three-level correction as a first-level correction and a second-level correction; Judgment correction module: Obtain the temperature data of the built-in temperature sensor and the discharge current to judge whether the original end voltage of the on-line capacity verification is reasonable. If it is unreasonable, use the three-level correction. If it is reasonable, comprehensively judge the correction level in combination with the charging state consistency and capacity attenuation of the battery, and correct the original end voltage to the corrected end voltage; Selection function module: Determine whether to select an exponential attenuation function or a linear attenuation function as the selected attenuation function based on the accuracy requirements of the discharge process and whether the original end voltage is reasonable; Attenuation processing module: Use the selected attenuation function and the corrected end voltage to process the voltage attenuation process of the on-line capacity verification; Load correction: Select a PTC resistor corresponding to the rated power and the initial resistance value, connect the PTC resistor in series in the discharge circuit of the storage battery, and denote the PTC resistor as , denote the discharge current of the storage battery as I, and the load correction is expressed as: = I × , where I is the discharge current of the storage battery, is the PTC resistor; Temperature compensation correction: Record the operating ambient temperature of the battery measured by the temperature sensor as T, obtain the temperature-voltage characteristic curve of the battery, and obtain the current standard temperature based on the curve , then the temperature deviation , and the temperature compensation correction is expressed as: , where α is determined by different types of batteries; Aging correction: Record the number of charge and discharge cycles of the battery as n, and record the voltage correction value corresponding to the increase in internal resistance by x% each time. , the internal resistance increases by z% every y cycles. Calculate the internal resistance increase ratio p = ny × z%. The voltage correction value caused by the increase in internal resistance is expressed as: = p × , assuming the increase in internal resistance is ΔR, determine the relationship coefficient k between the increase in internal resistance and the voltage correction value according to the aging model of different types of batteries. The voltage correction value caused by the increase in internal resistance is expressed as: = k × ΔR. Then the final aging correction value is expressed as: + ; The original cut-off voltage is , add the temperature compensation correction value , the aging correction value and the PTC resistor load correction value to obtain the corrected cut-off voltage ; The importance ranking of the three correction measures is: temperature compensation > aging correction > PTC resistance load. Adding the PTC resistance load is used as the load correction. Combining the aging correction and the temperature compensation to correct the original cut-off voltage of the battery is used as the three-level correction. According to the importance of the three correction measures, only using the aging correction and the temperature compensation to correct the original cut-off voltage of the battery is used as the two-level correction. The corrected cut-off voltage is expressed as: , only using the temperature compensation to correct the original cut-off voltage of the battery is used as the one-level correction. The corrected cut-off voltage is expressed as: .

2. The on-line monitoring and intelligent capacity verification device for a storage battery according to claim 1, wherein: Record the operating ambient temperature of the battery measured by the temperature sensor as T, record the discharge current of the battery as I, establish a relationship model of temperature-discharge current-cutoff voltage, substitute the obtained temperature T and discharge current I into the reference model, and calculate the theoretically reasonable cutoff voltage range. to , and at the same time obtain the actual cutoff voltage during the current online capacity verification process. When or , it is determined that the original cutoff voltage is unreasonable and three-level correction is required. When , it is determined that the original cutoff voltage is reasonable, and then the correction level is further judged. Judgment on the consistency of charging status: Obtain the battery charging history record, and count the number of times that the charging voltage exceeds the upper limit of the target charging voltage in the recent charging cycles and the number of times that it is lower than the lower limit of the target charging voltage , when + = 0, it is considered that the charging status is good; when + ≤ 2, it is considered that the charging status is relatively consistent; if + > 2, it is considered that the charging status is inconsistent; Let the total number of charging cycles be N. When + = 0, S = 0; when + ≤ 2, S = × 0.5; when + > 2, S = ; Judgment of capacity attenuation: Based on the rated capacity of the battery and the actual capacity Q measured recently, calculate the capacity retention rate C = . When C ≥ 90%, it is defined as mild attenuation; when 80% ≤ C < 90%, it is defined as moderate attenuation; if C < 80%, it is defined as severe attenuation; When C≥90%, D = 0; when 80%≤C<90%, D=(90%−C)×10; when C<80%, D=(90%−C)×20; Comprehensively judge the correction level in combination with the charging state consistency and capacity attenuation of the battery: First-level correction: When S = 0 and D = 0, only temperature compensation correction is required, and the correction level is the first level; Second-level correction: When S<=0.3 and D<=10, in addition to temperature compensation, capacity attenuation is considered for correction, and the correction level is the second level; Third-level correction: When S>0.3 or D>10, comprehensively consider the charging state, capacity attenuation, and temperature compensation for correction, and the correction level is the third level.

3. The on-line monitoring and intelligent capacity verification device for a storage battery according to claim 2, wherein: Obtain the historical operation data of the storage battery system that has been put into use, analyze the historical data, obtain the accuracy requirements of the discharge process, and set a threshold to judge the level of the accuracy requirements of the discharge process; After receiving the accuracy requirements of the discharge process and whether the original end voltage is reasonable, the selection function module defines the accuracy requirements of the discharge process and whether the original end voltage is reasonable as input variables, and divides them into different fuzzy sets respectively; Define the selected attenuation function as the output variable and divide it into a fuzzy set; Formulate fuzzy rules to describe the influence of the accuracy requirements of the discharge process and whether the original end voltage is reasonable on the selected attenuation function; Perform fuzzy inference according to the fuzzy rules to determine the selected attenuation function.

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