Ship battery soc estimation method and system based on energy benchmark dynamic reconstruction

Abstract

The present application relates to the technical field of ship power battery management, and particularly relates to a ship battery SOC estimation method and system based on energy benchmark dynamic reconstruction, which comprises the following steps: firstly, initializing the system energy benchmark and calculating the initial total energy of the system; in operation, tracking and updating the current total energy of the system through real-time integration and system-level efficiency compensation; when a battery cluster switching event is detected, calculating the carried energy based on the SOC and capacity of the switched cluster, and dynamically reconstructing the current total energy of the system to eliminate the SOC jump; when the charging is completed or the discharging reaches the cutoff condition, forcibly calibrating the system SOC and synchronously updating the total energy of the system to eliminate the accumulated error and achieve safety protection; finally, calculating and outputting the high-precision battery system SOC based on the reconstructed and calibrated total energy of the system and the online cluster total capacity. The present application solves the SOC estimation inaccuracy and jump problem in the multi-cluster parallel dynamic switching scene, and improves the safety of ship navigation.

Description

Technical Field

[0001] This invention relates to the field of marine power battery management technology, and in particular to a method and system for estimating the state of charge (SOC) of marine batteries based on dynamic reconfiguration of energy references. Background Technology

[0002] To meet power and range requirements, large electric ships generally use multiple battery clusters connected in parallel to form a power battery system. In actual operation, the system needs to dynamically "connect" (connect to the system) and "disconnect" (remove from the system) the battery clusters according to faults, maintenance, or performance status.

[0003] Existing technologies typically use the arithmetic mean method to calculate the total system SOC. This method has inherent flaws: it carries the risk of SOC fluctuations and "phantom charge" issues. The averaging method cannot reflect the physical energy changes caused by switching events. Switching out a faulty cluster with an overestimated SOC can cause the system SOC to drop instantly, while adding a "phantom charge" cluster can instantly raise the system SOC, severely misleading the navigation process. Furthermore, the accuracy of the system SOC depends entirely on the accuracy of the SOC value reported by each battery cluster. If the SOC of a single cluster is inaccurately estimated due to factors such as temperature, internal resistance, and aging, its error will directly contaminate the total system SOC through the averaging method. Summary of the Invention

[0004] To overcome the above shortcomings, this invention provides a method and system for estimating the SOC of ship batteries based on dynamic reconfiguration of energy benchmarks. It aims to improve the problem of inaccurate SOC estimation of ship power battery systems in complex application scenarios with multiple battery clusters connected in parallel and dynamically switched.

[0005] In a first aspect, the present invention provides the following technical solution: a method for estimating the State of Charge (SOC) of a ship battery based on dynamic reconstruction of an energy reference, comprising the following steps:

[0006] Obtain the rated capacity and initial SOC value of all initial online battery clusters, and calculate the initial total energy of the system based on the rated capacity and initial SOC value of all initial online battery clusters;

[0007] The total voltage and total current of the battery system are collected, the net energy change of the battery system is integrated in real time, and a system-level efficiency compensation model is introduced to correct the integration result to obtain the compensated net energy change. Then, the current total energy of the system is calculated based on the initial total energy of the system and the compensated net energy change.

[0008] The contactor status of each battery cluster is monitored in real time to detect switching events. When a battery cluster switching event is detected, the energy carried by the switched battery cluster is calculated based on the SOC value and rated capacity, and the total energy of the current system is reconstructed accordingly.

[0009] When the battery system is fully charged or the discharge reaches the set cutoff condition, the battery system SOC is forcibly calibrated, and the current total energy of the battery system is updated synchronously based on the calibration result.

[0010] The SOC of the battery system is calculated based on the total energy of the current battery system after reconstruction and calibration, and the sum of the rated capacities of all currently online battery clusters.

[0011] Preferably, the calculation process for the initial total energy of the system includes:

[0012] After the battery system is powered on, read the rated capacity of all initial online battery clusters;

[0013] Obtain the initial SOC values ​​of all initial online battery clusters using a high-precision method;

[0014] Calculate the initial total energy of the system based on the rated capacity and the initial SOC value.

[0015] Preferably, the process for obtaining the net energy change includes:

[0016] Based on the total voltage and total current, the net energy change of the system is obtained in real time by using the ampere-hour integration method or the power integration method.

[0017] A system-level efficiency compensation model is introduced to correct the net energy change, resulting in a compensated net energy change.

[0018] Preferably, the calculation process for the total energy of the current system includes:

[0019] Obtain the initial total energy of the system and the net energy change after compensation;

[0020] The initial total energy of the system is algebraically added to the net energy change after compensation, and the result of the addition is used as the updated current total energy of the system.

[0021] Preferably, the process for calculating the energy carried by a battery cluster based on its SOC value and rated capacity includes:

[0022] When the contactor status signal changes, a battery cluster switching event is detected;

[0023] If it is a cluster cutting event, before disconnecting the contactor of the battery cluster, obtain its final SOC value and rated capacity before cutting, and calculate the energy carried by the cut battery cluster as the product of the final SOC value and the rated capacity.

[0024] If it is a clustering event, before closing the contactor of the battery cluster, obtain its synchronous SOC value and rated capacity after calibration by the open-circuit voltage method at the moment of grid connection, and calculate the energy carried by the clustered battery as the product of the synchronous SOC value and the rated capacity.

[0025] Preferably, the process of reconstructing the total energy of the current system includes:

[0026] If it is a cluster-cutting event, the energy carried by the cut-cluster battery is subtracted from the current total system energy, and the result of the subtraction is used as the reconstructed current total system energy;

[0027] If it is a clustering event, the current total energy of the system is added to the energy carried by the clustered battery clusters, and the result of the addition is used as the current total energy of the reconstructed system.

[0028] Preferably, the process for forcibly calibrating the battery system's state of charge (SOC) includes:

[0029] When the battery system is in the charging phase and the charging current is continuously detected to be lower than or equal to the first set threshold, the system is determined to be fully charged, and the battery system SOC is forcibly calibrated to 100%.

[0030] When the system is in the discharge phase and continuously detects that the voltage of any single cell in any online battery cluster is lower than or equal to the second set threshold, it determines that the discharge has reached the set cutoff condition and forces the battery system SOC to be calibrated to a preset low power alarm value.

[0031] Preferably, the process for synchronously updating the total energy of the current battery system includes:

[0032] When the battery system SOC is forced to be calibrated, obtain the sum of the rated capacities of all currently online battery clusters;

[0033] The new total energy of the battery system is calculated by summing the calibrated SOC value and the rated capacity.

[0034] Update the current total energy of the battery system to the new total energy of the battery system.

[0035] Preferably, the calculation process for the battery system's State of Charge (SOC) includes:

[0036] Obtain the total energy of the current battery system after reconstruction and calibration, and obtain the sum of the rated capacities of all currently online battery clusters;

[0037] Divide the total energy of the current battery system by the sum of the rated capacities, and output the resulting quotient as the battery system's State of Charge (SOC).

[0038] Secondly, the present invention provides the following technical solution: a ship battery SOC estimation system based on dynamic reconstruction of energy reference, the system comprising the following modules:

[0039] The energy baseline initialization module is used to obtain the rated capacity and initial SOC value of all initial online battery clusters, and calculate the initial total energy of the system based on the rated capacity and initial SOC value of all initial online battery clusters.

[0040] The energy tracking module is used to collect the total voltage and total current of the battery system, integrate the net energy change of the battery system in real time, and introduce a system-level efficiency compensation model to correct the integration result, so as to obtain the compensated net energy change. Then, the current total energy of the system is calculated based on the initial total energy of the system and the compensated net energy change.

[0041] The dynamic reconfiguration module is used to monitor the contactor status of each battery cluster in real time to detect switching events. When a battery cluster switching event is detected, the module calculates the energy carried by the switched battery cluster based on its SOC value and rated capacity, and reconfigures the total energy of the current system accordingly.

[0042] The system calibration module is used to force calibration of the battery system SOC when the battery system is fully charged or the discharge reaches a set cutoff condition, and to synchronously update the current total energy of the battery system based on the calibration results.

[0043] The SOC calculation output module is used to calculate the SOC of the battery system based on the total energy of the current battery system after reconstruction and calibration and the sum of the rated capacities of all currently online battery clusters.

[0044] The present invention has the following beneficial effects:

[0045] 1. In this invention, by dynamically reconstructing the energy benchmark, the total energy of the system is corrected from a physical level when the battery cluster is switched on and off, so that the output value of the system's SOC can smoothly and continuously reflect the changes in the system's real energy. This solves the problem of instantaneous SOC jumps and virtual electricity caused by the traditional arithmetic average method, and provides a highly reliable data basis for judging the ship's range.

[0046] 2. In this invention, by introducing a dual mechanism of system-level efficiency compensation and system-level SOC calibration, a system-level high-precision estimation system that does not completely depend on the accuracy of the SOC algorithm of a single battery cluster is constructed. This method can self-correct the cumulative error of ampere-hour integration and perform absolute calibration of the SOC at the end of charging and discharging, thereby significantly improving the overall estimation accuracy of the system under complex operating conditions.

[0047] 3. In this invention, by providing a true and reliable SOC, the risk of power loss due to misjudgment of power is avoided. On the other hand, a voltage-SOC collaborative calibration mechanism at the end of the discharge stage is introduced. When the voltage of any single cell in any battery cluster reaches the cutoff threshold, the system SOC is immediately forcibly intervened, realizing active safety protection based on the weakest link, and effectively preventing battery over-discharge and the chain safety accidents such as thermal runaway that may be caused. Attached Figure Description

[0048] Figure 1 This is a flowchart illustrating the ship battery SOC estimation method based on dynamic reconfiguration of energy reference proposed in this invention.

[0049] Figure 2 This is a schematic diagram of the architecture of the ship battery SOC estimation system based on dynamic reconstruction of energy benchmark proposed in this invention. Detailed Implementation

[0050] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0051] Example 1:

[0052] In a first embodiment of the present invention, the present invention provides a method for estimating the state of charge (SOC) of a ship battery based on dynamic reconfiguration of an energy reference, such as... Figures 1-2 As shown, it includes the following steps:

[0053] Obtain the rated capacity and initial SOC value of all initial online battery clusters, and calculate the initial total energy of the system based on the rated capacity and initial SOC value of all initial online battery clusters.

[0054] Furthermore, the calculation process for the initial total energy of the system includes:

[0055] After the battery system is powered on, read the rated capacity of all initial online battery clusters;

[0056] Obtain the initial SOC values ​​of all initial online battery clusters using a high-precision method;

[0057] Calculate the initial total energy of the system based on the rated capacity and the initial SOC value.

[0058] Specifically, after the ship's battery system is powered on and completes its self-test, the system's main controller reads the rated capacity of all initially online battery clusters through the communication bus. The rated capacity is an inherent parameter calibrated at the factory of the battery clusters, and is usually stored in the battery management unit of each cluster in ampere-hours or kilowatt-hours. Subsequently, the system obtains the initial SOC value of all initially online battery clusters. This initial SOC value is preferably measured using a high-precision method. Specifically, during a rest period after the system is powered on and before the load is applied, the open-circuit voltage of each battery cluster is measured, and the high-precision initial SOC value of each cluster is obtained by looking up a table based on the pre-calibrated open-circuit voltage and SOC correspondence curve.

[0059] After obtaining the rated capacity and initial SOC value of all initial online battery clusters, the initial total energy of the system is calculated. The formula for calculating the initial total energy of the system is:

[0060] The initial total energy of the system = Σ(the initial SOC value of the i-th battery cluster × the rated capacity of the i-th battery cluster);

[0061] Where Σ represents the summation of the products of all initial online battery clusters;

[0062] In a specific embodiment, for example, in a system containing four battery clusters each with a rated capacity of 100kWh, if the initial SOC values ​​measured by the above high-precision method are 95%, 90%, 98%, and 92%, respectively, the initial total energy of the system is calculated as follows: Initial total energy of the system = 95%×100kWh + 90%×100kWh + 98%×100kWh + 92%×100kWh = 375kWh;

[0063] The initial total energy of the system obtained from this calculation will serve as the baseline starting point for all subsequent energy tracking and state estimation.

[0064] The total voltage and total current of the battery system are collected, the net energy change of the battery system is integrated in real time, and a system-level efficiency compensation model is introduced to correct the integration result to obtain the compensated net energy change. Then, the current total energy of the system is calculated based on the initial total energy of the system and the compensated net energy change.

[0065] Furthermore, the process for obtaining the net energy change includes:

[0066] Based on the total voltage and total current, the net energy change of the system is obtained in real time by using the ampere-hour integration method or the power integration method.

[0067] A system-level efficiency compensation model is introduced to correct the net energy change, resulting in the compensated net energy change.

[0068] Furthermore, the current calculation process for the total energy of the system includes:

[0069] Obtain the initial total energy of the system and the net energy change after compensation;

[0070] The initial total energy of the system is algebraically added to the net energy change after compensation, and the result is used as the updated current total energy of the system.

[0071] Specifically, the battery system continuously collects the total voltage U and total current I of the battery system. Based on the total voltage and total current, it uses either the ampere-hour integration method or the power integration method to accumulate the net energy change of the system in real time. If the ampere-hour integration method is used, the net energy change... Through formula The calculation is performed, where the integral term is the cumulative number of joules, and dividing by 3600 converts the energy unit to kilowatt-hours;

[0072] If the power integration method is used, the power is directly integrated, and the net energy change is obtained through the formula. The calculation is performed, where U×I / 1000 converts the instantaneous power unit to kilowatts, and the energy unit after integration is kilowatt-hours;

[0073] During the integration process, a system-level efficiency compensation model is introduced to correct the aforementioned net energy change. This system-level efficiency compensation model comprehensively considers charging and discharging efficiency and auxiliary equipment power consumption. The charging and discharging efficiency η is obtained by looking up a table, which uses the system's average temperature and average current as input parameters, and the auxiliary equipment power consumption... This is obtained by real-time summarization of the energy consumption of the battery management system, thermal management system, and water pump;

[0074] The formula for calculating efficiency compensation for net energy change is:

[0075] Net energy change after compensation ;

[0076] Where ΔE is the original net energy change obtained by the ampere-hour integration method or the power integration method, during charging, For charging efficiency, its value is less than 1. During discharging, For discharge efficiency, its value is also less than 1;

[0077] After obtaining the compensated net energy change, the current total system energy is calculated based on the initial total system energy. The formula for calculating the current total system energy is:

[0078] ;

[0079] in, The initial total energy of the system is given by the formula, which uses algebraic addition to update the total energy of the system in real time.

[0080] The contactor status of each battery cluster is monitored in real time to detect switching events. When a battery cluster switching event is detected, the energy carried by the switched battery cluster is calculated based on the SOC value and rated capacity, and the total energy of the current system is reconstructed accordingly.

[0081] Furthermore, the process for calculating the energy carried by a battery cluster based on its SOC value and rated capacity includes:

[0082] When the contactor status signal changes, a battery cluster switching event is detected;

[0083] If it is a cluster cutting event, before disconnecting the contactor of the battery cluster, obtain its final SOC value and rated capacity before cutting, and calculate the energy carried by the cut battery cluster as the product of the final SOC value and the rated capacity.

[0084] If it is a clustering event, before closing the contactor of the battery cluster, obtain its synchronous SOC value and rated capacity after calibration by the open-circuit voltage method at the moment of grid connection, and calculate the energy carried by the clustered battery as the product of the synchronous SOC value and the rated capacity.

[0085] Furthermore, the process of reconfiguring the current total system energy includes:

[0086] If it is a cluster-cutting event, the energy carried by the cut-cluster battery is subtracted from the current total energy of the system, and the result of the subtraction is used as the current total energy of the reconstructed system.

[0087] If it is a clustering event, the current total energy of the system is added to the energy carried by the clustered battery clusters, and the result of the addition is used as the current total energy of the reconstructed system.

[0088] Specifically, the system's main controller continuously monitors the auxiliary contact status signals of each battery cluster contactor via a digital input channel or communication bus. When the contactor status signal of any battery cluster changes from closed to open, or from open to closed, a battery cluster switching event is detected. If the detected event is a cluster switching event, before executing the command to disconnect the contactor of that battery cluster, the system first obtains the latest final SOC value of the switched-out cluster, reported by the battery management unit of that cluster, through internal communication. and read its rated capacity. Then, the removed energy carried by the cut cluster of batteries was calculated. The calculation formula is as follows:

[0089] ;

[0090] If the detected event is a battery clustering event, before executing the command to close the contactor of the battery cluster, the system first controls the battery cluster to be connected to remain stationary in an unloaded state for a preset time to stabilize its terminal voltage. Subsequently, its open-circuit voltage is measured, and based on the relationship curve between open-circuit voltage and SOC, the synchronous SOC value calibrated at the moment of grid connection is obtained by looking up a table. At the same time, read its rated capacity. Subsequently, the energy carried by the cluster of batteries was calculated. The calculation formula is as follows:

[0091] ;

[0092] After calculating the energy carried by the switched battery clusters, immediately adjust the current total energy of the system. Perform the corresponding reconstruction. If it is a cluster-cutting event, the total energy of the reconstructed system is calculated using the following formula:

[0093] ;

[0094] If it is a clustering event, the total energy of the reconstructed system is calculated using the following formula:

[0095] ;

[0096] After the reconstruction is complete, the system will The value assigned This serves as the new total energy of the current system, used for subsequent system SOC calculations.

[0097] When the battery system is fully charged or the discharge reaches the set cutoff condition, the battery system SOC is forcibly calibrated, and the total energy of the current battery system is updated synchronously based on the calibration results.

[0098] Furthermore, the process for forcibly calibrating the battery system's state of charge (SOC) includes:

[0099] When the battery system is in the charging phase and the charging current is continuously detected to be lower than or equal to the first set threshold, the system is determined to be fully charged, and the battery system SOC is forcibly calibrated to 100%.

[0100] When the system is in the discharge phase and continuously detects that the voltage of any single cell in any online battery cluster is lower than or equal to the second set threshold, it determines that the discharge has reached the set cutoff condition and forces the battery system SOC to be calibrated to a preset low power alarm value.

[0101] Furthermore, the current process for synchronizing and updating the total energy of the battery system includes:

[0102] When the battery system SOC is forced to be calibrated, obtain the sum of the rated capacities of all currently online battery clusters;

[0103] The new total energy of the battery system is calculated based on the sum of the calibrated SOC value and the rated capacity.

[0104] Update the current total energy of the battery system to the new total energy of the battery system.

[0105] Specifically, when the battery system is charging, the system continuously monitors the total charging current. When the charging current remains below or equal to a first set threshold, such as 0.05 times the total system capacity, and is maintained for a preset period of time, the system determines that charging is complete. At this point, the system forcibly calibrates the battery system's State of Charge (SOC) to 100%. When the battery system is discharging, the system continuously monitors the voltage of each individual cell in all online battery clusters. When the voltage of any individual cell in any online battery cluster remains below or equal to a second set threshold, such as 2.5 volts, the system determines that discharging has reached the set cutoff condition. At this point, the system forcibly calibrates the battery system's SOC to a preset low-charge alarm value, which is set to 5%.

[0106] After completing the mandatory calibration of the battery system's SOC, the system immediately updates the current total energy of the battery system based on the calibration results. The system first obtains the rated capacity of all currently online battery clusters and calculates the sum of their rated capacities. Subsequently, the system calculates the new total energy of the battery system based on the calibrated SOC value of the battery system. The calculation formula is as follows:

[0107] New battery system total energy = Calibrated battery system SOC × ;

[0108] Finally, the system updates the current total battery system energy to the calculated new total battery system energy. In a specific embodiment, for example, during the charging completion calibration, if the current online cluster total rated capacity is 300kWh, the new total system energy is updated to 100% × 300kWh = 300kWh. During the discharge cutoff calibration, the total system energy is updated to 5% × 300kWh = 15kWh. This update operation ensures that the energy reference is strictly synchronized with the calibrated SOC state, providing an accurate starting point for subsequent precise estimation.

[0109] The SOC of the battery system is calculated based on the total energy of the current battery system after reconstruction and calibration, and the sum of the rated capacities of all currently online battery clusters.

[0110] Furthermore, the calculation process for the battery system's State of Charge (SOC) includes:

[0111] Obtain the total energy of the current battery system after reconstruction and calibration, and obtain the sum of the rated capacities of all currently online battery clusters;

[0112] Divide the total energy of the current battery system by the sum of the rated capacities, and output the quotient as the state of charge (SOC) of the battery system.

[0113] Specifically, the system's main controller obtains the total energy of the current battery system after processing through all the aforementioned steps. This energy value already incorporates the combined results of real-time integral compensation, switching event reconstruction, and forced calibration. Simultaneously, the system's main controller acquires the rated capacity of all currently online battery clusters and calculates the sum of their rated capacities. Subsequently, the system calculates the final SOC value of the battery system based on the sum of the current total energy of the battery system and the rated capacity of the current online battery clusters. The calculation formula is as follows:

[0114] Battery system SOC = ( / ) × 100%;

[0115] The formula converts the calculated quotient into a percentage. The system's main controller uses this calculated battery system SOC value as the final result and outputs it through the vehicle communication network for the ship's upper-level energy management system, display instruments, and operators to monitor the status, assess the remaining range, and make operational decisions. In a specific embodiment, at a certain moment, if the current total energy of the battery system is 235kWh and the sum of the rated capacities of all currently online battery clusters is 300kWh, then the system calculates the battery system SOC as (235 / 300)×100%=78.3% and outputs this result.

[0116] This calculation step is executed cyclically within each control cycle of the system operation to ensure that the output battery system SOC value can reflect the true state of charge of the ship's power battery system in real time and accurately.

[0117] Example 2:

[0118] Existing technologies typically use the arithmetic mean method to calculate the total SOC of a system. This method has inherent drawbacks: it carries the risk of SOC fluctuations and "phantom charge" errors. The averaging method cannot reflect the physical energy changes caused by switching events. Switching out a fault cluster with an overestimated SOC can cause the system SOC to drop instantly, while adding a "phantom charge" cluster can instantly raise the system SOC, severely misleading navigation decisions. Furthermore, the accuracy of the system SOC depends entirely on the accuracy of the SOC value reported by each battery cluster. If the SOC of a single cluster is inaccurately estimated due to factors such as temperature, internal resistance, and aging, the error will directly contaminate the total system SOC through the averaging method. To solve the above problems, this invention provides a ship battery SOC estimation system based on dynamic reconstruction of an energy benchmark, the structure of which is as follows: Figure 2 As shown. The specific implementation process of this system is as follows:

[0119] The energy baseline initialization module is used to obtain the rated capacity and initial SOC value of all initial online battery clusters, and calculate the initial total energy of the system based on the rated capacity and initial SOC value of all initial online battery clusters.

[0120] The energy tracking module is used to collect the total voltage and total current of the battery system, integrate the net energy change of the battery system in real time, and introduce a system-level efficiency compensation model to correct the integration result, so as to obtain the compensated net energy change. Then, the current total energy of the system is calculated based on the initial total energy of the system and the compensated net energy change.

[0121] The dynamic reconfiguration module is used to monitor the contactor status of each battery cluster in real time to detect switching events. When a battery cluster switching event is detected, the module calculates the energy carried by the switched battery cluster based on its SOC value and rated capacity, and reconfigures the total energy of the current system accordingly.

[0122] The system calibration module is used to force calibration of the battery system SOC when the battery system is fully charged or the discharge reaches the set cutoff condition, and to update the current total energy of the battery system synchronously based on the calibration results;

[0123] The SOC calculation output module is used to calculate the SOC of the battery system based on the total energy of the current battery system after reconstruction and calibration and the sum of the rated capacities of all currently online battery clusters.

[0124] Specifically, the energy reference initialization module communicates with the battery management unit of each battery cluster. After the system is powered on, the module reads the rated capacity of all initial online battery clusters and obtains their initial SOC value measured by the high-precision open-circuit voltage method. Based on the rated capacity and initial SOC value of all initial online battery clusters, the module calculates the initial total energy of the system. The calculation formula is: initial total energy of the system = Σ(initial SOC value of the i-th battery cluster × rated capacity of the i-th battery cluster).

[0125] The energy tracking module is electrically connected to the high-voltage sampling unit and current sensor of the battery system. This module collects the total voltage and total current of the battery system and integrates the net energy change of the battery system in real time using the ampere-hour integration method or the power integration method. The module has a built-in system-level efficiency compensation model, which comprehensively considers the charge and discharge efficiency obtained from the table based on the average temperature and average current of the system, as well as the power consumption of auxiliary equipment accumulated in real time, and corrects the net energy change obtained by integration to obtain the compensated net energy change. The module then calculates the current total energy of the system based on the initial total energy of the system and the compensated net energy change. The calculation formula is: Current total energy of the system = Initial total energy of the system + Compensated net energy change.

[0126] The dynamic reconfiguration module is electrically connected to the contactor drive circuit or status feedback node of each battery cluster. This module monitors the contactor status signal of each battery cluster in real time to detect switching events. When a battery cluster switching event is detected, the module calculates the energy carried by the battery cluster based on the SOC value and rated capacity of the switching battery cluster. Specifically, for a switching event, the final SOC value is obtained and the energy carried is calculated before the contactor is disconnected. For a paralleling event, the synchronous SOC value calibrated by the open-circuit voltage method is obtained and the energy carried is calculated before the contactor is closed. The module then reconfigures the total energy of the current system accordingly, performing subtraction when switching and addition when paralleling.

[0127] The system calibration module communicates with the battery system's charger, load, and battery management unit of each battery cluster. This module determines the battery system's operating status. When the system is in the charging stage and the charging current is consistently below the first set threshold, it forces the battery system's SOC to be calibrated to 100%. When the system is in the discharging stage and the voltage of any single cell in any online battery cluster is consistently below the second set threshold, it forces the battery system's SOC to be calibrated to a preset low-power alarm value. After completing the SOC calibration, the module synchronously updates the current total energy of the battery system based on the calibration results. The calculation formula is: New total system energy = calibrated SOC × sum of the rated capacities of all currently online battery clusters.

[0128] The SOC calculation output module is integrated with the system main controller. This module obtains the current total energy of the battery system after processing by the dynamic reconfiguration module and the system calibration module, as well as the sum of the rated capacities of all currently online battery clusters. It calculates the battery system SOC by performing a division operation. The calculation formula is: Battery system SOC = Current battery system total energy / Sum of the rated capacities of all currently online battery clusters. This module outputs the calculated battery system SOC value through the communication interface.

[0129] All of the above modules work together through the software program inside the system's main controller, and can be selectively implemented by dedicated hardware circuits, to jointly complete the high-precision and high-reliability estimation of the SOC of the ship's battery system.

[0130] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for estimating the State of Charge (SOC) of a ship's battery based on dynamic reconstruction of an energy benchmark, characterized in that, Includes the following steps: Obtain the rated capacity and initial SOC value of all initial online battery clusters, and calculate the initial total energy of the system based on the rated capacity and initial SOC value of all initial online battery clusters; The total voltage and total current of the battery system are collected, the net energy change of the battery system is integrated in real time, and a system-level efficiency compensation model is introduced to correct the integration result to obtain the compensated net energy change. Then, the current total energy of the system is calculated based on the initial total energy of the system and the compensated net energy change. The contactor status of each battery cluster is monitored in real time to detect switching events. When a battery cluster switching event is detected, the energy carried by the switched battery cluster is calculated based on the SOC value and rated capacity, and the total energy of the current system is reconstructed accordingly. When the battery system is fully charged or the discharge reaches the set cutoff condition, the battery system SOC is forcibly calibrated, and the current total energy of the battery system is updated synchronously based on the calibration results. The SOC of the battery system is calculated based on the total energy of the current battery system after reconstruction and calibration and the sum of the rated capacities of all currently online battery clusters. The process for calculating the energy carried by a battery cluster based on its SOC value and rated capacity includes: When the contactor status signal changes, a battery cluster switching event is detected; If it is a cluster cutting event, before disconnecting the contactor of the battery cluster, obtain its final SOC value and rated capacity before cutting, and calculate the energy carried by the cut battery cluster as the product of the final SOC value and the rated capacity. If it is a clustering event, before closing the contactor of the battery cluster, obtain its synchronous SOC value and rated capacity after calibration by the open-circuit voltage method at the moment of grid connection, and calculate the energy carried by the clustered battery cluster as the product of the synchronous SOC value and the rated capacity. The process of reconstructing the total energy of the current system includes: If it is a cluster-cutting event, the energy carried by the cut-cluster battery is subtracted from the current total system energy, and the result of the subtraction is used as the reconstructed current total system energy; If it is a clustering event, the current total energy of the system is added to the energy carried by the clustered battery clusters, and the result of the addition is used as the current total energy of the reconstructed system.

2. The method for estimating the state of charge (SOC) of a ship battery based on dynamic reconstruction of an energy reference as described in claim 1, characterized in that, The calculation process for the initial total energy of the system includes: After the battery system is powered on, read the rated capacity of all initial online battery clusters; Obtain the initial SOC values ​​of all initial online battery clusters using a high-precision method; Calculate the initial total energy of the system based on the rated capacity and the initial SOC value.

3. The method for estimating the state of charge (SOC) of a ship battery based on dynamic reconstruction of an energy reference as described in claim 1, characterized in that, The process for obtaining the net energy change includes: Based on the total voltage and total current, the net energy change of the system is obtained in real time by using the ampere-hour integration method or the power integration method. A system-level efficiency compensation model is introduced to correct the net energy change, resulting in a compensated net energy change.

4. The method for estimating the state of charge (SOC) of a ship battery based on dynamic reconstruction of an energy reference as described in claim 3, characterized in that, The calculation process for the total energy of the current system includes: Obtain the initial total energy of the system and the net energy change after compensation; The initial total energy of the system is algebraically added to the net energy change after compensation, and the result of the addition is used as the updated current total energy of the system.

5. The method for estimating the state of charge (SOC) of a ship battery based on dynamic reconstruction of an energy reference as described in claim 1, characterized in that, The process for forcibly calibrating the battery system's state of charge (SOC) includes: When the battery system is in the charging phase and the charging current is continuously detected to be lower than or equal to the first set threshold, the system is determined to be fully charged, and the battery system SOC is forcibly calibrated to 100%. When the system is in the discharge phase and continuously detects that the voltage of any single cell in any online battery cluster is lower than or equal to the second set threshold, it determines that the discharge has reached the set cutoff condition and forces the battery system SOC to be calibrated to a preset low power alarm value.

6. The method for estimating the state of charge (SOC) of a ship battery based on dynamic reconstruction of an energy reference as described in claim 1, characterized in that, The process for synchronizing and updating the total energy of the current battery system includes: When the battery system SOC is forced to be calibrated, obtain the sum of the rated capacities of all currently online battery clusters; The new total energy of the battery system is calculated by summing the calibrated SOC value and the rated capacity. Update the current total energy of the battery system to the new total energy of the battery system.

7. The method for estimating the state of charge (SOC) of a ship battery based on dynamic reconstruction of an energy reference as described in claim 1, characterized in that, The calculation process for the battery system's State of Charge (SOC) includes: Obtain the total energy of the current battery system after reconstruction and calibration, and obtain the sum of the rated capacities of all currently online battery clusters; Divide the total energy of the current battery system by the sum of the rated capacities, and output the quotient as the state of charge (SOC) of the battery system.

8. A ship battery SOC estimation system based on dynamic reconstruction of energy reference, characterized in that, The system for estimating the state of charge (SOC) of a ship battery based on dynamic reconfiguration of an energy reference, as described in any one of claims 1-7, comprises the following modules: The energy baseline initialization module is used to obtain the rated capacity and initial SOC value of all initial online battery clusters, and calculate the initial total energy of the system based on the rated capacity and initial SOC value of all initial online battery clusters. The energy tracking module is used to collect the total voltage and total current of the battery system, integrate the net energy change of the battery system in real time, and introduce a system-level efficiency compensation model to correct the integration result, so as to obtain the compensated net energy change. Then, the current total energy of the system is calculated based on the initial total energy of the system and the compensated net energy change. The dynamic reconfiguration module is used to monitor the contactor status of each battery cluster in real time to detect switching events. When a battery cluster switching event is detected, the module calculates the energy carried by the switched battery cluster based on its SOC value and rated capacity, and reconfigures the total energy of the current system accordingly. The system calibration module is used to force calibration of the battery system SOC when the battery system is fully charged or the discharge reaches a set cutoff condition, and to synchronously update the current total energy of the battery system based on the calibration results. The SOC calculation output module is used to calculate the SOC of the battery system based on the total energy of the current battery system after reconstruction and calibration and the sum of the rated capacities of all currently online battery clusters. The process for calculating the energy carried by a battery cluster based on its SOC value and rated capacity includes: When the contactor status signal changes, a battery cluster switching event is detected; If it is a cluster cutting event, before disconnecting the contactor of the battery cluster, obtain its final SOC value and rated capacity before cutting, and calculate the energy carried by the cut battery cluster as the product of the final SOC value and the rated capacity. If it is a clustering event, before closing the contactor of the battery cluster, obtain its synchronous SOC value and rated capacity after calibration by the open-circuit voltage method at the moment of grid connection, and calculate the energy carried by the clustered battery cluster as the product of the synchronous SOC value and the rated capacity. The process of reconstructing the total energy of the current system includes: If it is a cluster-cutting event, the energy carried by the cut-cluster battery is subtracted from the current total system energy, and the result of the subtraction is used as the reconstructed current total system energy; If it is a clustering event, the current total energy of the system is added to the energy carried by the clustered battery clusters, and the result of the addition is used as the current total energy of the reconstructed system.

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