A battery energy optimization scheduling method and system for new energy vehicles

Abstract

The application provides a battery energy optimization scheduling method and system for new energy vehicles, determines the instantaneous potential of the positive electrode relative to the reference electrode according to the end voltage, current and temperature of the vehicle battery; determines the safe potential window from the lower limit critical potential and the upper limit critical potential of irreversible capacity loss, and presets the boundary approximation band; when the instantaneous potential enters the boundary approximation band, determines the safe current boundary according to the transient response sensitivity of the current, and obtains the loss current limiting boundary by taking the upper limit of the life loss rate as a constraint; when the instantaneous potential does not exceed the safe window, according to the energy interaction income signal of demand response compensation, dynamically adjusts the charging and discharging power within the power envelope corresponding to the loss current limiting boundary, so as to maximize the instantaneous energy interaction income; when the instantaneous potential exceeds the safe window, the income optimization is exited. The application can realize the collaborative optimization of the safety life constraint and the energy interaction income under the positive electrode reference electrode potential in real time.

Description

Technical Field

[0001] This application relates to the field of new energy vehicle battery management technology, and more specifically, to a battery energy optimization scheduling method and system for new energy vehicles. Background Technology

[0002] As the requirements for driving range and battery life of new energy vehicles continue to increase, battery energy management strategies need to finely control the charging and discharging process under dynamic driving conditions. Battery management systems typically use terminal voltage or state of charge as the basic criteria for charging and discharging boundaries, and introduce energy interaction optimization on this basis to improve energy utilization efficiency or obtain demand response compensation within the battery's allowable operating range. Since the driving power demand and the internal electrochemical state of the battery fluctuate in real time during the driving process of new energy vehicles, establishing a method that can accurately sense the internal electrode potential of the battery and dynamically adjust the charging and discharging power within the safe operating range is a key technical direction for improving vehicle energy efficiency and ensuring battery life.

[0003] In related technologies, the determination of charge and discharge safety boundaries mostly relies on comparing the measured value of the battery terminal voltage with a preset empirical threshold. However, the terminal voltage reflects the algebraic sum of the positive and negative electrode potentials and cannot characterize the actual electrochemical state of a single electrode. When the positive electrode potential is close to the critical potential corresponding to lithium plating at the negative electrode or the critical potential of irreversible phase transition of the positive electrode active material, the terminal voltage may still be within the preset safety threshold range. This causes the determination of the safety boundary to lag behind the actual degradation risk inside the electrode. In addition, even if some methods attempt to introduce more conservative current limits to avoid irreversible capacity loss, such fixed limits cannot be linked and quantified with the real-time changing electrode potential margin and the upper limit of lifetime loss rate. It is difficult to provide a usable dynamic power adjustment space for energy interaction benefit optimization within the safety critical region. Under the dual constraints of the response lag of the safety boundary and the lack of quantification of the power adjustment space, existing methods are unable to incorporate safety lifetime constraints and energy interaction benefits into the same control framework for coordinated optimization based on the real-time reconstruction of the positive electrode reference potential. Therefore, how to achieve synergistic optimization of safe lifetime constraints and energy interaction benefits under real-time reconfiguration of the positive electrode reference potential has become a challenge for the industry. Summary of the Invention

[0004] This application provides a battery energy optimization scheduling method and system for new energy vehicles, which can realize the synergistic optimization of safe lifetime constraints and energy interaction benefits under real-time reconfiguration of the positive electrode reference potential.

[0005] In a first aspect, this application provides a battery energy optimization scheduling method for new energy vehicles, comprising the following steps:

[0006] During vehicle operation, the instantaneous potential of the positive electrode relative to the reference electrode is determined by a pre-calibrated electrochemical-thermal coupling state estimator based on the battery's terminal voltage, current, and temperature.

[0007] The safety potential window is determined by the lower and upper critical potentials of irreversible capacity loss, and a boundary approximation zone is preset in the region adjacent to the lower and upper critical potentials within the safety potential window.

[0008] When the instantaneous potential enters the boundary approach zone, based on the transient response sensitivity of the instantaneous potential to the current, a safe current boundary that does not trigger irreversible capacity loss is determined, and the safe current boundary is reduced by a pre-calibrated upper limit of lifetime loss rate to obtain the loss current limiting boundary.

[0009] When the instantaneous potential does not exceed the safe potential window, the on-board power converter is controlled to dynamically adjust the charging and discharging power within the power envelope corresponding to the loss current limiting boundary, based on the energy interaction benefit signal of the demand response compensation, so as to maximize the instantaneous energy interaction benefit.

[0010] When the instantaneous potential exceeds any boundary of the safe potential window, the benefit optimization is terminated, and the charging and discharging power is forcibly reduced to the preset safe power until the instantaneous potential returns to within the safe potential window.

[0011] In some embodiments, the pre-calibrated electrochemical-thermal coupled state estimator consists of a reduced-order electrochemical model and a closed-loop state observer. The reduced-order electrochemical model characterizes the kinetics of lithium-ion diffusion and interfacial charge transfer reactions in the solid phase of the battery cathode, and its key parameters are corrected by coupling temperature effects through Arrhenius relations. The closed-loop state observer uses the residual between the measured value of the terminal voltage and the model prediction value as feedback to perform online joint estimation of the cathode steady-state potential and polarization potential, and outputs the instantaneous potential of the cathode relative to the reference electrode.

[0012] In some embodiments, based on the battery's terminal voltage, current, and temperature, the instantaneous potential of the positive electrode relative to the reference electrode is determined using a pre-calibrated electrochemical-thermal coupled state estimator, specifically including:

[0013] The real-time collected terminal voltage, current and temperature are input into the reduced-order electrochemical model to obtain the prior estimate of the positive electrode potential and the model-predicted terminal voltage.

[0014] The prior estimate, the real-time acquired terminal voltage, and the model-predicted terminal voltage are input into the closed-loop state observer. The closed-loop state observer is driven by the residual between the measured terminal voltage and the model-predicted terminal voltage to perform closed-loop correction on the estimates of the positive electrode steady-state potential and polarization potential, and outputs the instantaneous potential of the positive electrode relative to the reference electrode.

[0015] In some embodiments, the safety potential window is determined by the lower and upper critical potentials of irreversible capacity loss, specifically including:

[0016] By using a reference electrode test, the potential corresponding to lithium plating on the negative electrode was calibrated as the lower critical potential.

[0017] By using a reference electrode test, the potential corresponding to the irreversible phase transition of the positive electrode active material or the violent oxidative decomposition of the electrolyte is determined as the upper limit critical potential.

[0018] The open interval between the lower critical potential and the upper critical potential is defined as the safe potential window.

[0019] In some embodiments, a predefined boundary approximation zone is defined in the region adjacent to the lower and upper critical potentials within the safety potential window, specifically including:

[0020] The lower limit critical potential is floated by a preset voltage bias as the upper boundary of the lower approximation band, and the upper limit critical potential is floated by a preset voltage bias as the lower boundary of the upper approximation band.

[0021] The region between the lower critical potential and the upper boundary of the lower approximation band, and the region between the lower boundary of the upper approximation band and the upper critical potential, are respectively preset as the lower boundary approximation band and the upper boundary approximation band;

[0022] The preset voltage bias is dynamically adjusted according to the current lifespan loss rate.

[0023] In some embodiments, a safe current boundary that does not trigger irreversible capacity loss is determined based on the transient response sensitivity of the instantaneous potential to the current, specifically including:

[0024] Obtain the impedance state quantity generated by the electrochemical-thermal coupled state estimator during the solution of the instantaneous potential, and use the amplitude of the impedance state quantity as the transient response sensitivity of the potential to the current in the current state;

[0025] The impedance state quantity integrates the contributions of ohmic internal resistance, charge transfer impedance, and diffusion impedance.

[0026] If the instantaneous potential enters the lower boundary approach zone, the safe current boundary is obtained by dividing the difference between the instantaneous potential and the lower critical potential by the transient response sensitivity.

[0027] If the instantaneous potential enters the upper boundary approach zone, the safe current boundary is obtained by dividing the difference between the upper critical potential and the instantaneous potential by the transient response sensitivity.

[0028] In some embodiments, the safe current boundary is reduced by taking a pre-calibrated upper limit of the lifetime loss rate as a constraint to obtain the loss current limiting boundary, specifically including:

[0029] Query the pre-calibrated mapping table between the upper limit of the lifetime wear rate and the current amplitude and the current state of charge to determine the allowable current amplitude that satisfies the upper limit of the lifetime wear rate constraint under the current operating conditions.

[0030] The amplitude of the safe current boundary is compared with the allowable current amplitude, and the smaller value of the two is selected as the amplitude of the loss current limiting boundary.

[0031] The direction of the loss current limiting boundary is consistent with the direction of the safe current boundary.

[0032] In some embodiments, based on the energy interaction benefit signal of demand response compensation, the on-board power converter is controlled to dynamically adjust the charging and discharging power within the power envelope corresponding to the loss current limiting boundary, so as to maximize the instantaneous energy interaction benefit, specifically including:

[0033] The system continuously receives real-time feedback of energy loss characteristic indicators from the vehicle drive system and uses these energy loss characteristic indicators as a component of the energy interaction benefit signal.

[0034] The energy loss characteristic index is constructed based on at least one of the following: the current operating point efficiency of the motor, the switching loss of the inverter, and the power consumption of the high-voltage accessories.

[0035] The upper and lower limits of allowable charging and discharging power are determined by multiplying the loss current limiting boundary with the current terminal voltage.

[0036] Within the envelope formed by the upper and lower power limits, with the goal of minimizing the total system loss characterized by the energy loss characteristic index, a local optimization problem is solved to obtain the target charging and discharging power command, which is then sent to the on-board power converter for execution.

[0037] In some embodiments, when the instantaneous potential exceeds any boundary of the safe potential window, the benefit optimization is exited, and the charging and discharging power is forcibly reduced to a preset safe power until the instantaneous potential recovers to within the safe potential window. Specifically, this includes:

[0038] When the instantaneous potential is detected to exceed the upper limit critical potential or fall below the lower limit critical potential, the current energy interaction benefit optimization process is immediately terminated.

[0039] The charging and discharging power is controlled to return to a preset safe power at a preset safe ramp rate, wherein the preset safe power is zero power or trickle power to maintain the vehicle's basic load;

[0040] The instantaneous potential is continuously monitored. Once it is confirmed that the potential has stably fallen back to within the safe potential window and entered the region outside the boundary approach zone, the benefit optimization process is re-enabled after a preset delay.

[0041] Secondly, this application provides a battery energy optimization scheduling system for new energy vehicles, comprising:

[0042] The potential estimation module is used to determine the instantaneous potential of the positive electrode relative to the reference electrode during vehicle operation, based on the battery's terminal voltage, current, and temperature, through a pre-calibrated electrochemical-thermal coupling state estimator.

[0043] The window setting module is used to determine the safe potential window based on the lower and upper critical potentials of irreversible capacity loss, and to preset a boundary approximation zone in the region adjacent to the lower and upper critical potentials within the safe potential window.

[0044] The current limiting decision module is used to determine a safe current boundary that does not trigger irreversible capacity loss based on the transient response sensitivity of the instantaneous potential to the current when the instantaneous potential enters the boundary approach zone, and to reduce the safe current boundary by taking a pre-calibrated upper limit of the lifetime loss rate as a constraint to obtain the loss current limiting boundary.

[0045] The optimization scheduling module is used to control the on-board power converter to dynamically adjust the charging and discharging power within the power envelope corresponding to the loss current limiting boundary, based on the energy interaction benefit signal of the demand response compensation when the instantaneous potential does not exceed the safe potential window, so as to maximize the instantaneous energy interaction benefit.

[0046] The over-limit protection module is used to exit the benefit optimization when the instantaneous potential exceeds any boundary of the safe potential window, and to forcibly reduce the charging and discharging power to a preset safe power until the instantaneous potential returns to within the safe potential window.

[0047] The technical solutions provided by the embodiments disclosed in this application have the following beneficial effects:

[0048] This application uses an electrochemical-thermal coupled state estimator to shift the control reference from the terminal voltage to the positive electrode reference potential. Based on this, a hierarchical constraint system is constructed, consisting of a safety potential window, a boundary approximation band, and a loss current-limiting boundary. Ultimately, within the safety constraint envelope, dynamic optimization of charge and discharge power is performed with the goal of minimizing total system loss. First, a reduced-order electrochemical model and a closed-loop state observer are used to reconstruct the instantaneous potential of the positive electrode online, establishing a quantitative correlation between the determination of the safety boundary and the critical conditions of electrochemical degradation mechanisms such as lithium plating at the negative electrode and irreversible phase transition at the positive electrode. Second, a boundary approximation band is preset within the safety potential window, shifting the timing of safety management intervention to the potential approximation stage, and based on the transient response of the instantaneous potential to the current... The safety current boundary is calculated based on sensitivity, and then the minimum generation loss current limit boundary is taken as a constraint of the upper limit of lifetime loss rate, thus coupling the electrochemical safety limit and the upper limit of lifetime loss rate into the same real-time current constraint. Finally, the energy loss characteristic index fed back by the vehicle drive system in real time is used as the benefit signal, and the local optimization problem is solved within the power envelope corresponding to the loss current limit boundary with the goal of minimizing the total system loss. This allows the charging and discharging power to actively avoid the inefficient area of ​​the motor and the high loss area of ​​the inverter under the dual hard constraints of safety and lifetime. In summary, this application achieves the synergistic optimization of safety lifetime constraints and energy interaction benefits through the progressive synergy of online electrode potential reconstruction, hierarchical safety boundary quantification, and loss minimization optimization within constraints. Attached Figure Description

[0049] Figure 1 This is an exemplary flowchart of a battery energy optimization scheduling method for new energy vehicles, as shown in some embodiments of this application.

[0050] Figure 2 This is a flowchart illustrating the process of determining the loss current limiting boundary according to some embodiments of this application;

[0051] Figure 3 This is a schematic diagram of the structure of a battery energy optimization scheduling system for new energy vehicles, as shown in some embodiments of this application;

[0052] Figure 4 This is a schematic diagram of the structure of a computer device for implementing a battery energy optimization scheduling method for new energy vehicles, according to some embodiments of this application. Detailed Implementation

[0053] To better understand the technical solution of this application, the technical solution of this application will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0054] refer to Figure 1The figure is an exemplary flowchart of a battery energy optimization scheduling method for new energy vehicles according to some embodiments of this application. The battery energy optimization scheduling method for new energy vehicles mainly includes the following steps:

[0055] In step 101, during vehicle operation, the instantaneous potential of the positive electrode relative to the reference electrode is determined by a pre-calibrated electrochemical-thermal coupling state estimator based on the battery's terminal voltage, current, and temperature.

[0056] It should be noted that the pre-calibrated electrochemical-thermal coupled state estimator in this application consists of a reduced-order electrochemical model and a closed-loop state observer. The reduced-order electrochemical model characterizes the kinetics of lithium-ion diffusion and interfacial charge transfer reactions in the solid phase of the battery cathode, and its key parameters are corrected by coupling temperature effects through Arrhenius relations. The closed-loop state observer uses the residual between the measured terminal voltage and the model prediction as feedback to perform online joint estimation of the cathode steady-state potential and polarization potential, outputting the instantaneous potential of the cathode relative to the reference electrode. In specific implementation, the electrochemical-thermal coupled state estimator can be pre-calibrated in the following manner:

[0057] A reduced-order electrochemical model is established. Based on the cathode material system and structural parameters of the target battery, a single-particle model or a single-particle model with electrolyte correction is constructed to characterize the diffusion of lithium ions in the cathode solid phase and the reaction kinetics of the interface charge transfer reaction. The model state variables include at least the lithium concentration on the cathode solid phase surface and the cathode steady-state potential. The model parameters include the solid phase diffusion coefficient, reaction rate constant, solid phase particle radius, effective diffusion length, etc. For the temperature-sensitive terms among the above parameters, the pre-exponential factor and activation energy in the Arrhenius expression of each parameter are obtained by electrochemical impedance spectroscopy or constant current intermittent titration at different temperatures, and the correction relationship of temperature on key parameters is established.

[0058] A closed-loop state observer is constructed, using the reduced-order electrochemical model as the nominal model for the observer's prediction stage. An extended Kalman filter or a Romberg observer is selected as the closed-loop correction structure. The terminal voltage is taken as the observed quantity, and the positive electrode steady-state potential and polarization potential are taken as the state variables to be estimated. The state-space equation of the observer is established. The observer gain matrix can be designed based on the linearization results of the model at typical operating points, using the pole placement method or by solving the Riccati equation offline to obtain the steady-state gain matrix.

[0059] Calibration and verification: On a three-electrode battery or half-cell experimental platform with a reference electrode, the terminal voltage, current, temperature, and measured potential data of the positive electrode relative to the reference electrode under different temperatures and rate conditions are collected. The measured terminal voltage, current, and temperature are input into the constructed state estimator. The instantaneous potential output by the estimator is compared with the measured potential of the reference electrode. The root mean square error (RMSE) of the two is used as an indicator to perform offline optimization tuning of the undetermined parameters and observer gain in the reduced-order electrochemical model. The offline optimization tuning adopts the gradient descent method or particle swarm optimization algorithm, with the minimum RMSE as the optimization objective. The parameters to be tuned are iteratively adjusted until the RMSE converges to the preset accuracy threshold, thus completing the calibration of the electrochemical-thermal coupled state estimator.

[0060] It should be noted that the reference electrode in this application refers to the virtual lithium metal electrode used to provide a true reference for the positive electrode potential during the calibration stage of the state estimator.

[0061] In some embodiments, the instantaneous potential of the positive electrode relative to the reference electrode is determined based on the battery's terminal voltage, current, and temperature using a pre-calibrated electrochemical-thermal coupled state estimator. This can be achieved through the following steps:

[0062] The real-time collected terminal voltage, current and temperature are input into the reduced-order electrochemical model to obtain the prior estimate of the positive electrode potential and the model-predicted terminal voltage.

[0063] The prior estimate, the real-time acquired terminal voltage, and the model-predicted terminal voltage are input into the closed-loop state observer. The closed-loop state observer is driven by the residual between the measured terminal voltage and the model-predicted terminal voltage to perform closed-loop correction on the estimates of the positive electrode steady-state potential and polarization potential, and outputs the instantaneous potential of the positive electrode relative to the reference electrode.

[0064] In this application, the prior estimate refers to the initial estimate of the positive electrode potential calculated by the reduced-order electrochemical model based on the real-time acquired terminal voltage, current, and temperature before correction by the closed-loop state observer; the model-predicted terminal voltage refers to the terminal voltage prediction value obtained by the reduced-order electrochemical model based on the prior estimate of the positive electrode potential, the estimate of the negative electrode potential, and the ohmic voltage drop, used to calculate the residual with the real-time acquired terminal voltage; the instantaneous potential is used as a real-time quantitative characterization of the positive electrode electrochemical state.

[0065] In practice, firstly, the real-time acquired terminal voltage, current, and temperature are used as inputs to a pre-constructed reduced-order electrochemical model. This reduced-order electrochemical model is a mathematical model characterizing the kinetics of lithium-ion diffusion and interfacial charge transfer reactions in the solid phase of the battery's positive electrode, containing the positive electrode solid-phase diffusion equation and a description of the interfacial electrochemical reaction. After receiving the real-time acquired terminal voltage, current, and temperature, the lithium concentration distribution inside the positive electrode solid-phase particles is recursively calculated based on the current internal state variables, and the positive electrode potential is calculated based on the interfacial reaction kinetic equation. The estimated positive electrode potential and the negative electrode potential are then combined. The estimated potential value and the ohmic voltage drop generated by the current and ohmic internal resistance are used to calculate the predicted battery terminal voltage corresponding to the current state. The key temperature-related parameters in the reduced-order electrochemical model include the solid-phase diffusion coefficient and the interfacial reaction rate constant. In each calculation step, the temperature is collected in real time and corrected online through the pre-calibrated Arrhenius relation. This calculation process does not require any measurement feedback correction. Therefore, the positive electrode potential value directly calculated based on the current input and internal state is used as the prior estimate of the positive electrode potential, and the calculated battery terminal voltage value is used as the predicted terminal voltage of the model.

[0066] Then, the prior estimate of the positive electrode potential, the real-time acquired terminal voltage, and the model-predicted terminal voltage are used as inputs to the closed-loop state observer. The closed-loop state observer internally maintains estimates of the positive electrode steady-state potential and polarization potential. After receiving the input, it calculates the difference between the measured terminal voltage and the model-predicted terminal voltage, which is the terminal voltage residual. Using a pre-designed feedback gain matrix, the terminal voltage residual is mapped to a correction amount for the positive electrode steady-state potential estimate and the polarization potential estimate. The feedback gain matrix is ​​the steady-state gain obtained offline through pole placement or solving the algebraic Riccati equation, based on the linearized state-space equation of the reduced-order electrochemical model at typical operating points during the state estimator calibration stage. The calculated correction amount is then superimposed on the current positive electrode steady-state potential estimate and polarization potential estimate to complete the closed-loop correction of these two estimates. The sum of the corrected positive electrode steady-state potential estimate and the polarization potential estimate is the positive electrode potential, which is used as the final output instantaneous potential of the positive electrode relative to the reference electrode.

[0067] In step 102, a safe potential window is determined by the lower and upper critical potentials of the irreversible capacity loss, and a boundary approximation zone is preset in the region adjacent to the lower and upper critical potentials within the safe potential window.

[0068] In some embodiments, the safety potential window is determined by the lower and upper critical potentials of irreversible capacity loss, which can be achieved by the following steps:

[0069] By using a reference electrode test, the potential corresponding to lithium plating on the negative electrode was calibrated as the lower critical potential.

[0070] By using a reference electrode test, the potential corresponding to the irreversible phase transition of the positive electrode active material or the violent oxidative decomposition of the electrolyte is determined as the upper limit critical potential.

[0071] The open interval between the lower critical potential and the upper critical potential is defined as the safe potential window.

[0072] The lower critical potential in this application is the potential value used to define the lower limit boundary of the potential at which lithium plating does not occur at the negative electrode during the charging and discharging process of the battery; the upper critical potential is the potential value used to define the upper limit boundary of the potential at which the positive electrode active material does not undergo irreversible phase transition and the electrolyte does not undergo severe oxidative decomposition during the charging and discharging process of the battery; the safe potential window is an open interval used to limit the allowable operating range of the instantaneous potential of the positive electrode relative to the reference electrode.

[0073] In practice, firstly, the battery is tested at different temperatures and charge / discharge rates on a three-electrode battery with a reference electrode. The negative electrode potential measured by the reference electrode is monitored simultaneously. When the negative electrode potential drops to zero volts or a negative value relative to the reference electrode, it indicates that lithium plating has begun on the negative electrode surface. The potential value of the positive electrode relative to the reference electrode at the moment when the negative electrode potential drops to zero volts is recorded. The most conservative value is selected from the positive electrode potential values ​​obtained from multiple tests, while a preset safety margin is reserved. The final determined potential value is calibrated as the lower limit critical potential. The safety margin is dynamically determined according to the degree of battery aging. The lower the battery health status, the larger the safety margin value is, in order to compensate for the shift in potential characteristics after aging.

[0074] Secondly, charging tests were conducted on a three-electrode battery or a positive half-cell with a reference electrode at different temperatures and charging rates. The positive electrode potential measured by the reference electrode was monitored simultaneously. When the positive electrode potential continued to rise to a certain potential point, a potential plateau appeared on the charging curve or a characteristic peak appeared on the differential capacity curve. This potential point is the potential inflection point at which the positive electrode active material undergoes an irreversible phase transition. At the same time, the starting potential of gas generation inside the battery or electrolyte decomposition during the charging process was monitored. The smaller potential value between the potential inflection point of the irreversible phase transition of the positive electrode active material and the starting potential of the violent oxidation and decomposition of the electrolyte was taken, while a preset safety margin was reserved. The final determined potential value was calibrated as the upper limit critical potential.

[0075] Then, the lower critical potential is used as the lower boundary of the safety potential window, and the upper critical potential is used as the upper boundary of the safety potential window. The open interval between the lower critical potential and the upper critical potential is defined as the safety potential window. Within the range defined by this safety potential window, the instantaneous potential of the positive electrode relative to the reference electrode is both higher than the lower critical potential and lower than the upper critical potential. The battery charging and discharging process will not trigger irreversible capacity loss such as negative electrode lithium plating, irreversible phase change of positive electrode active material, or violent oxidation and decomposition of electrolyte. The open interval between the lower critical potential and the upper critical potential is used as the safety potential window.

[0076] In some embodiments, a predefined boundary approximation zone is established in the region adjacent to the lower and upper critical potentials within the safety potential window. This can be achieved using the following steps:

[0077] The lower limit critical potential is floated by a preset voltage bias as the upper boundary of the lower approximation band, and the upper limit critical potential is floated by a preset voltage bias as the lower boundary of the upper approximation band.

[0078] The region between the lower critical potential and the upper boundary of the lower approximation band, and the region between the lower boundary of the upper approximation band and the upper critical potential, are respectively preset as the lower boundary approximation band and the upper boundary approximation band;

[0079] The preset voltage bias is dynamically adjusted according to the current lifespan loss rate.

[0080] In this application, the lower boundary approach band is used to indicate the warning potential range in which the instantaneous potential of the positive electrode relative to the reference electrode has approached the lower limit critical potential from the inner region of the safe potential window and needs to trigger the calculation of the safe current boundary; the upper boundary approach band is used to indicate the warning potential range in which the instantaneous potential of the positive electrode relative to the reference electrode has approached the upper limit critical potential from the inner region of the safe potential window and needs to trigger the calculation of the safe current boundary.

[0081] In specific implementation, firstly, the current lifespan degradation rate is obtained. This rate is the percentage of capacity decay per unit time or unit energy throughput estimated online based on the battery capacity decay model. Then, according to a pre-established first mapping relationship—a correspondence between the lifespan degradation rate and the voltage bias—calibrated through offline aging experiments, the minimum voltage bias that effectively prevents irreversible capacity loss is tested and recorded at different lifespan degradation rate levels, forming a table of the correspondence between lifespan degradation rate and voltage bias. When the lifespan degradation rate increases, the voltage bias increases accordingly to expand the coverage of the boundary approach band, thereby triggering the safe current boundary calculation earlier and strengthening battery protection. When the lifespan degradation rate decreases, the voltage bias decreases accordingly to narrow the coverage of the boundary approach band, thereby optimizing energy interaction benefits. This allows for greater adjustment space; then, based on the current lifespan degradation rate, the first mapping relationship is queried to obtain the voltage bias that should be used; the lower critical potential is summed with this voltage bias to obtain the upper boundary of the lower approximation band; the upper critical potential is subtracted from this voltage bias to obtain the lower boundary of the upper approximation band; then, within the safe potential window, the continuous potential range sandwiched between the lower critical potential and the upper boundary of the lower approximation band is preset as the lower boundary approximation band; the continuous potential range sandwiched between the lower boundary of the upper approximation band and the upper critical potential is preset as the upper boundary approximation band; when the instantaneous potential of the positive electrode relative to the reference electrode enters the lower boundary approximation band, it indicates that the instantaneous potential is close to the lower critical potential, and there is a risk of lithium plating on the negative electrode; when the instantaneous potential of the positive electrode relative to the reference electrode enters the upper boundary approximation band, it indicates that the instantaneous potential is close to the upper critical potential, and there is a risk of irreversible phase transition of the positive electrode active material or severe oxidation and decomposition of the electrolyte.

[0082] In step 103, when the instantaneous potential enters the boundary approach zone, a safe current boundary that does not trigger irreversible capacity loss is determined based on the transient response sensitivity of the instantaneous potential to the current. The safe current boundary is then reduced by taking the pre-calibrated upper limit of the lifetime loss rate as a constraint to obtain the loss current limiting boundary.

[0083] It should be noted that when the instantaneous potential enters the boundary approach zone, it means that the potential of the positive electrode relative to the reference electrode has deviated from the central safe zone of the safe potential window and is approaching the critical potential corresponding to irreversible capacity loss. The battery charging and discharging process has entered a warning state where the current amplitude needs to be actively constrained to prevent irreversible capacity loss.

[0084] In some embodiments, the safe current boundary that does not trigger irreversible capacity loss can be determined based on the transient response sensitivity of the instantaneous potential to the current. This can be achieved by the following steps:

[0085] Obtain the impedance state quantity generated by the electrochemical-thermal coupled state estimator during the solution of the instantaneous potential, and use the amplitude of the impedance state quantity as the transient response sensitivity of the potential to the current in the current state;

[0086] The impedance state quantity integrates the contributions of ohmic internal resistance, charge transfer impedance, and diffusion impedance.

[0087] If the instantaneous potential enters the lower boundary approach zone, the safe current boundary is obtained by dividing the difference between the instantaneous potential and the lower critical potential by the transient response sensitivity.

[0088] If the instantaneous potential enters the upper boundary approach zone, the safe current boundary is obtained by dividing the difference between the upper critical potential and the instantaneous potential by the transient response sensitivity.

[0089] The safe current boundary in this application is used to limit the maximum permissible charge and discharge current amplitude that will not trigger the positive electrode potential to exceed the lower or upper critical potential during charging and discharging within the boundary approach band, thereby preventing irreversible capacity loss.

[0090] In specific implementation, the impedance state quantity generated by the electrochemical-thermal coupled state estimator during the solution of the instantaneous potential can be obtained, and the amplitude of the impedance state quantity can be used as the transient response sensitivity of the potential to the current under the current state. This can be achieved in the following way: When the electrochemical-thermal coupled state estimator performs state estimation in each control cycle, in addition to outputting the instantaneous potential of the positive electrode relative to the reference electrode, it also synchronously generates an internal state quantity reflecting the current impedance level during the joint solution of the reduced-order electrochemical model and the closed-loop state observer. This internal state quantity is composed of three impedance contributions: the first part is the ohmic internal resistance, corresponding to the electrolyte ion conduction, electrode electronic conduction, and the connection between the current collector and the tab. The first part is the ohmic voltage drop; the second part is the charge transfer impedance, which corresponds to the electrochemical polarization resistance when lithium-ion insertion and extraction occur at the interface between the positive electrode and the electrolyte; the third part is the diffusion impedance, which corresponds to the concentration polarization resistance caused by the diffusion of lithium ions inside the solid particles of the positive electrode; the electrochemical-thermal coupled state estimator corrects the temperature dependence of the charge transfer impedance and diffusion impedance according to the real-time temperature in each control cycle through the Arrhenius relation, to ensure that the impedance state quantity reflects the true internal resistance level at the current temperature; the impedance state quantity, which integrates the contributions of ohmic internal resistance, charge transfer impedance and diffusion impedance, is obtained, and its amplitude is taken, which is defined as the transient response sensitivity of the potential to the current in the current state.

[0091] In specific implementation, if the instantaneous potential enters the lower boundary approach zone, the safe current boundary can be obtained by dividing the difference between the instantaneous potential and the lower critical potential by the transient response sensitivity. This can be achieved in the following way: When the instantaneous potential of the positive electrode relative to the reference electrode is detected to have fallen into the potential range defined by the lower boundary approach zone, the instantaneous potential is approaching the lower critical potential from the inner region of the safe potential window. At this time, the potential difference between the instantaneous potential and the lower critical potential is calculated. This potential difference represents the potential margin remaining between the current position of the instantaneous potential and the critical point of lithium plating of the negative electrode. The potential difference is divided by the transient response sensitivity, and the quotient is the maximum allowable discharge current amplitude under the constraint of the potential margin. This discharge current amplitude can ensure that the instantaneous potential will not exceed the lower critical potential during the discharge process. The calculated maximum discharge current amplitude is determined as the safe current boundary within the current lower boundary approach zone.

[0092] In specific implementation, if the instantaneous potential enters the upper boundary approach zone, the safe current boundary can be obtained by dividing the difference between the upper critical potential and the instantaneous potential by the transient response sensitivity. This can be achieved in the following way: When the instantaneous potential of the positive electrode relative to the reference electrode is detected to have fallen into the potential range defined by the upper boundary approach zone, the instantaneous potential is approaching the upper critical potential from the inner region of the safe potential window. At this time, the potential difference between the upper critical potential and the instantaneous potential is calculated. This potential difference represents the potential margin remaining between the current position of the instantaneous potential and the critical point of irreversible phase change of the positive electrode active material or violent oxidation and decomposition of the electrolyte. The potential difference is then divided by the transient response sensitivity, and the quotient is the maximum allowable charging current amplitude under the constraint of this potential margin. This charging current amplitude can ensure that the instantaneous potential will not exceed the upper critical potential during charging. Therefore, the maximum charging current amplitude calculated above can be determined as the safe current boundary within the current upper boundary approach zone.

[0093] In some embodiments, reference Figure 2 As shown in the figure, this is a flowchart illustrating the determination of the loss current limiting boundary according to some embodiments of this application. In this embodiment, the safe current boundary is reduced by a pre-calibrated upper limit of the lifetime loss rate to obtain the loss current limiting boundary, which can be achieved by the following steps:

[0094] In step 1031, the pre-calibrated mapping table of the upper limit of lifetime wear rate, current amplitude, and current state of charge is queried to determine the allowable current amplitude that satisfies the upper limit of lifetime wear rate constraint under the current operating condition.

[0095] In step 1032, the amplitude of the safe current boundary is compared with the allowable current amplitude, and the smaller of the two is selected as the amplitude of the loss current limiting boundary.

[0096] In step 1033, the direction of the loss current limiting boundary is consistent with the direction of the safe current boundary.

[0097] The loss current limiting boundary in this application is a current boundary that cannot be exceeded when the on-board power converter is used for charging and discharging power regulation within the boundary approach zone. Its amplitude is the smaller of the safe current boundary amplitude and the allowable current amplitude, and its direction is consistent with the direction of the safe current boundary.

[0098] In practice, firstly, a pre-calibrated mapping table between the upper limit of the lifespan degradation rate and the current amplitude and current state of charge is a three-dimensional mapping table established through battery cycle aging experiments during the offline calibration phase. The three dimensions of this mapping table are the upper limit of the lifespan degradation rate, the current amplitude, and the state of charge. The upper limit of the lifespan degradation rate is the allowable percentage of capacity decay per unit time set by the user or the system. In the offline experiment, the same batch of batteries is subjected to cycle aging tests at different current rates and different state of charge ranges. The number of cycles or time required for the capacity decay to reach a specific percentage under each operating condition is recorded. The correspondence between the current amplitude, the state of charge, and the lifespan degradation rate is calculated, and the upper limit of the current amplitude that meets the upper limit of the lifespan degradation rate constraint is extracted to form the mapping table. During online operation, the current state of charge of the battery is obtained, and the corresponding record is retrieved from the mapping table using the preset upper limit of the lifespan degradation rate and the current state of charge as the query index. The maximum current amplitude allowed under the condition of meeting the upper limit of the lifespan degradation rate is read, and this current amplitude is the allowable current amplitude.

[0099] Secondly, after obtaining the safe current boundary, the amplitude of the safe current boundary is extracted, and the amplitude of the safe current boundary is compared with the allowable current amplitude obtained by querying the mapping table. If the amplitude of the safe current boundary is less than or equal to the allowable current amplitude, the amplitude of the safe current boundary is used as the amplitude of the loss current limiting boundary; if the allowable current amplitude is less than the amplitude of the safe current boundary, the allowable current amplitude is used as the amplitude of the loss current limiting boundary, and the smaller value is selected as the amplitude of the loss current limiting boundary.

[0100] Then, the safe current boundary has a directional attribute. When the instantaneous potential enters the lower boundary approach zone, the direction of the safe current boundary is the discharge direction. When the instantaneous potential enters the upper boundary approach zone, the direction of the safe current boundary is the charging direction. The loss current limiting boundary inherits the direction of the safe current boundary. That is, the amplitude of the loss current limiting boundary and the direction of the safe current boundary are combined to form a complete current boundary with amplitude constraints and directional attributes. The current constraint with the above amplitude and direction is used as the loss current limiting boundary.

[0101] In step 104, when the instantaneous potential does not exceed the safe potential window, the on-board power converter is controlled to dynamically adjust the charging and discharging power within the power envelope corresponding to the loss current limiting boundary, based on the energy interaction benefit signal of the demand response compensation, so as to maximize the instantaneous energy interaction benefit.

[0102] It should be noted that when the instantaneous potential does not exceed the safe potential window, it indicates that the instantaneous potential of the positive electrode relative to the reference electrode is within the safe operating range, and the current electrochemical state has the prerequisite for performing the energy interaction benefit optimization process.

[0103] It should be noted that the energy interaction benefit signal for demand response compensation described in this application comes from sources including, but not limited to, demand response instructions issued by external power grid dispatching agencies. When not connected to the power grid or not receiving external instructions, the energy interaction benefit signal is constructed from the energy loss characteristic index fed back in real time by the vehicle drive system. This energy loss characteristic index reflects the total energy loss level of the system at the current operating point. Using it as an internal substitute for the benefit signal allows the vehicle to maximize its energy interaction benefit by optimizing its own losses without relying on external communication.

[0104] In some embodiments, based on the energy interaction benefit signal of demand response compensation, the on-board power converter is controlled to dynamically adjust the charging and discharging power within the power envelope corresponding to the loss current limiting boundary, so as to maximize the instantaneous energy interaction benefit. This can be achieved by the following steps:

[0105] The system continuously receives real-time feedback of energy loss characteristic indicators from the vehicle drive system and uses these energy loss characteristic indicators as a component of the energy interaction benefit signal.

[0106] The energy loss characteristic index is constructed based on at least one of the following: the current operating point efficiency of the motor, the switching loss of the inverter, and the power consumption of the high-voltage accessories.

[0107] The upper and lower limits of allowable charging and discharging power are determined by multiplying the loss current limiting boundary with the current terminal voltage.

[0108] Within the envelope formed by the upper and lower power limits, with the goal of minimizing the total system loss characterized by the energy loss characteristic index, a local optimization problem is solved to obtain the target charging and discharging power command, which is then sent to the on-board power converter for execution.

[0109] The upper and lower limits of charging and discharging power in this application are used to define the upper limit of charging power and the upper limit of discharging power that the on-board power converter is allowed to output under the condition of satisfying the loss current limiting boundary constraints; the target charging and discharging power command is a power setpoint used to enable the system to maximize energy interaction benefits in a way that minimizes the total system loss within the power envelope.

[0110] It should be noted that this application replaces the traditional fixed threshold limit or simple efficiency lookup table with minimizing the total system loss. It incorporates the copper and iron losses of the motor, the conduction and switching losses of the inverter, and the power consumption of high-voltage accessories into the optimization objective. It solves the local optimization problem within the power envelope corresponding to the loss current limit boundary, so that the adjustment of battery charging and discharging power can actively avoid the inefficient area of ​​the motor, the high loss area of ​​the inverter, and the superposition area of ​​power consumption of high-voltage accessories. Under the dual constraints of meeting the driving power requirements of the whole vehicle and not triggering irreversible capacity loss, it maximizes the proportion of the effective output power of the battery to the total power consumption of the system.

[0111] In practical implementation, the energy loss characteristic indicators continuously received from the vehicle drive system in real time can be achieved in the following way: During the operation of the vehicle drive system, the motor controller monitors the speed and torque of the motor at the current operating point in real time. Based on the motor efficiency pulse spectrum diagram pre-stored in the motor controller, it obtains the efficiency of the motor at the current operating point and calculates the power loss of the motor at the current operating point based on the difference between the input power and output power. This power loss includes copper loss and iron loss. The inverter control unit calculates the inverter switching loss in real time based on the current DC bus voltage, AC side current amplitude, and switching frequency through the inverter loss model. The conduction loss is calculated based on the DC bus voltage and current amplitude and the on-state voltage drop of the power devices, while the switching loss is calculated based on the DC bus voltage, current amplitude, and... The switching frequency is calculated, and the inverter switching loss is the sum of conduction loss and switching loss. The vehicle controller summarizes the high-voltage accessories currently in operation, including the DC-DC converter, air conditioning compressor, and cooling water pump, and collects the real-time power consumption of each accessory to obtain the power consumption of the high-voltage accessories. The power loss corresponding to the current operating point efficiency of the motor, the inverter switching loss, and the power consumption of the high-voltage accessories are summed to obtain a real-time estimate of the total system loss. This real-time estimate of the total system loss is used as an energy loss characteristic index. In each control cycle, the vehicle drive system sends this energy loss characteristic index as a real-time feedback quantity to the battery energy optimization scheduling controller. The battery energy optimization scheduling controller continuously receives this energy loss characteristic index and uses it as an energy interaction benefit signal.

[0112] In specific implementation, determining the allowable upper and lower limits of charging and discharging power by multiplying the loss current limiting boundary and the current terminal voltage can be achieved in the following way: Obtain the amplitude and direction of the loss current limiting boundary calculated in the current control cycle, and simultaneously collect the battery terminal voltage at the current moment. Then multiply the amplitude of the loss current limiting boundary by the current terminal voltage, and the resulting product is the maximum allowable charging and discharging power amplitude under the current loss current limiting boundary constraint. Determine the power direction according to the direction of the loss current limiting boundary. If the direction of the loss current limiting boundary is the discharging direction, the upper limit of the allowable discharging power is the maximum charging and discharging power amplitude, and the upper limit of the allowable charging power is zero. If the direction of the loss current limiting boundary is the charging direction, the upper limit of the allowable charging power is the maximum charging and discharging power amplitude, and the upper limit of the allowable discharging power is zero. Use the power upper limit determined by the amplitude and direction as the upper and lower limits of charging and discharging power.

[0113] In specific implementation, within the envelope formed by the upper and lower power limits, the goal is to minimize the total system loss represented by the energy loss characteristic index. A local optimization problem is solved to obtain the target charging / discharging power command, which is then sent to the on-board power converter for execution. This can be achieved as follows: The upper and lower power limits are used as the constraint boundaries of the optimization variables. The energy loss characteristic index corresponding to the energy interaction benefit signal is used as the cost term of the optimization objective function. A local optimization problem is constructed, where the optimization variable is the charging / discharging power command value. The constraint condition is that the charging / discharging power command value is within the power envelope formed by the upper and lower power limits, and the sum of the charging / discharging power command value and the current vehicle drive power demand is zero, thus satisfying the vehicle power balance. The current vehicle drive power demand is obtained by the vehicle controller based on the accelerator pedal opening and vehicle speed. The objective function is to minimize the total system loss represented by the energy loss characteristic index. Minimizing the total system loss under the constraint of satisfying the drive power demand is equivalent to minimizing the total system loss represented by the energy loss characteristic index. The goal is to maximize the difference between the battery output power and the total system loss, thereby maximizing the effective power used to drive the vehicle, i.e., maximizing instantaneous energy interaction benefits. Within the one-dimensional space of this power envelope, starting from the current charge / discharge power command value, an iterative search is performed in the direction of reducing the total system loss with a preset step size. The preset step size is determined based on a certain proportion of the difference between the upper and lower limits of the current charge / discharge power, with the certain proportion ranging from 5% to 10%. During the search process, each step verifies whether the charge / discharge power command value is within the power envelope, until the change in the total system loss obtained from two adjacent searches is less than a preset convergence threshold. The preset convergence threshold is set based on one-thousandth of the magnitude of the total system loss. The charge / discharge power value that minimizes the total system loss is obtained, and this charge / discharge power value is then used as the target charge / discharge power command. It is then sent to the on-board power converter through the on-board communication bus, and the current loop or power loop inside the on-board power converter performs closed-loop adjustment. The result obtained from solving the local optimization problem is used as the target charge / discharge power command.

[0114] In step 105, when the instantaneous potential exceeds any boundary of the safe potential window, the benefit optimization is exited, and the charging and discharging power is forcibly reduced to the preset safe power until the instantaneous potential returns to within the safe potential window.

[0115] It should be noted that when the instantaneous potential exceeds any boundary of the safe potential window, it means that the instantaneous potential of the positive electrode relative to the reference electrode has exceeded the safe operating range defined by the critical potential of irreversible capacity loss. The battery charging and discharging process has entered a risky state of lithium plating on the negative electrode, irreversible phase change of the positive electrode active material, or severe oxidation and decomposition of the electrolyte. The energy interaction benefit optimization process must be stopped immediately and the battery must be forcibly reverted to the preset safe power.

[0116] In some embodiments, when the instantaneous potential exceeds any boundary of the safe potential window, the benefit optimization is exited, and the charging and discharging power is forcibly reduced to a preset safe power until the instantaneous potential recovers to within the safe potential window. This can be achieved by the following steps:

[0117] When the instantaneous potential is detected to exceed the upper limit critical potential or fall below the lower limit critical potential, the current energy interaction benefit optimization process is immediately terminated.

[0118] The charging and discharging power is controlled to return to a preset safe power at a preset safe ramp rate, wherein the preset safe power is zero power or trickle power to maintain the vehicle's basic load;

[0119] The instantaneous potential is continuously monitored. Once it is confirmed that the potential has stably fallen back to within the safe potential window and entered the region outside the boundary approach zone, the benefit optimization process is re-enabled after a preset delay.

[0120] In practice, firstly, the battery energy optimization scheduling controller compares the instantaneous potential of the positive electrode relative to the reference electrode output by the electrochemical-thermal coupled state estimator with the pre-calibrated upper and lower critical potentials in real time during each control cycle. When the instantaneous potential value is greater than the upper critical potential or less than the lower critical potential, it is determined that the instantaneous potential has exceeded the safe potential window. During the current control cycle in which the boundary is determined to be exceeded, the operation of the revenue optimization solver is immediately stopped, and the instruction source of the on-board power converter is switched from the output of the revenue optimization solver to the preset safe power register, cutting off the revenue optimization process's right to regulate the charging and discharging power.

[0121] Secondly, after the revenue optimization process is terminated, the preset safe power value stored in the preset safe power register is obtained, and the preset safe ramp rate is also obtained. This safe ramp rate is a power change rate limit preset according to the battery management system protection strategy. Its value can ensure that no secondary impact of instantaneous potential will be caused by current change during the power rollback process. Starting from the current actual charging and discharging power, the amplitude of charging and discharging power is reduced in control cycles according to the safe ramp rate until the amplitude of charging and discharging power decays to the preset safe power. The preset safe power is configured as zero power or trickle power to maintain the vehicle's basic load according to the vehicle's safety requirements. Zero power means that there is no active power exchange between the battery and the drive system. Trickle power means that only the minimum power required to maintain the operation of the vehicle's basic load such as the power steering pump and brake vacuum pump is used. The power value that is stably output after the rollback is completed is used as the preset safe power.

[0122] Then, after the charging and discharging power returns to the preset safe power, the instantaneous potential output by the electrochemical-thermal coupled state estimator is continuously received, and the numerical change of the instantaneous potential is monitored in a control cycle manner. When the value of the instantaneous potential falls back to between the upper and lower critical potentials, it is determined that the instantaneous potential has returned to the safe potential window. Further, it continues to monitor whether the instantaneous potential is further away from the boundary approach zone. When the value of the instantaneous potential is above the upper boundary of the lower approach zone and below the lower boundary of the upper approach zone, it is determined that the instantaneous potential has entered outside the boundary approach zone. The core area of ​​the safety potential window; after confirming that the above two conditions are met simultaneously, a preset delay timer is started. The set value of the delay timer can filter out the instantaneous fluctuations of the instantaneous potential near the boundary, and prevent the profit optimization process from oscillating frequently at the boundary. When the delay timer reaches the preset time and the instantaneous potential remains in the core area of ​​the safety potential window outside the boundary approach zone throughout the timing period, the command source of the vehicle power converter is switched back to the output of the profit optimization solver, and the profit optimization solver resumes operation.

[0123] On the other hand, in some embodiments, this application provides a battery energy optimization scheduling system for new energy vehicles, with reference to... Figure 3 The figure is a schematic diagram of the structure of a battery energy optimization scheduling system for new energy vehicles according to some embodiments of this application. The battery energy optimization scheduling system for new energy vehicles includes: a potential estimation module 301, a window setting module 302, a current limiting decision module 303, an optimization scheduling module 304, and an over-limit protection module 305, which are described below:

[0124] The potential estimation module 301 is mainly used to determine the instantaneous potential of the positive electrode relative to the reference electrode during vehicle operation, based on the battery's terminal voltage, current and temperature, through a pre-calibrated electrochemical-thermal coupling state estimator.

[0125] The window setting module 302 is mainly used to determine the safe potential window based on the lower limit critical potential and the upper limit critical potential of irreversible capacity loss, and to preset the boundary approximation zone in the region adjacent to the lower limit critical potential and the upper limit critical potential within the safe potential window.

[0126] The current limiting decision module 303 is mainly used to determine the safe current boundary that does not trigger irreversible capacity loss based on the transient response sensitivity of the instantaneous potential to the current when the instantaneous potential enters the boundary approach zone, and to reduce the safe current boundary by taking the pre-calibrated upper limit of the lifetime loss rate as a constraint to obtain the loss current limiting boundary.

[0127] The optimization scheduling module 304 is mainly used to control the on-board power converter to dynamically adjust the charging and discharging power within the power envelope corresponding to the loss current limiting boundary, based on the energy interaction benefit signal of the demand response compensation when the instantaneous potential does not exceed the safe potential window, so as to maximize the instantaneous energy interaction benefit.

[0128] The over-limit protection module 305 is mainly designed to exit the benefit optimization when the instantaneous potential exceeds any boundary of the safe potential window, and to forcibly reduce the charging and discharging power to a preset safe power until the instantaneous potential returns to within the safe potential window.

[0129] In addition, this application also provides a computer device, which includes a memory and a processor. The memory stores code, and the processor is configured to acquire the code and execute the above-described battery energy optimization scheduling method for new energy vehicles.

[0130] In some embodiments, reference Figure 4 The figure is a schematic diagram of the structure of a computer device implementing a battery energy optimization scheduling method for new energy vehicles, according to some embodiments of this application. The battery energy optimization scheduling method for new energy vehicles in the above embodiments can be implemented through... Figure 4 The computer device shown is used to implement this, and the computer device includes at least one processor 401, a communication bus 402, a memory 403, and at least one communication interface 404.

[0131] Processor 401 can be a general-purpose central processing unit (CPU) or an application-specific integrated circuit (ASIC).

[0132] The communication bus 402 can be used to transmit information between the aforementioned components.

[0133] The memory 403 may be a read-only memory (ROM) or other type of static storage device capable of storing static information and instructions, random access memory (RAM) or other type of dynamic storage device capable of storing information and instructions, or electrically erasable programmable read-only memory (EEPROM), compact disc read-only memory (CD-ROM) or other optical disc storage, optical disc storage (including compressed optical discs, laser discs, optical discs, digital universal optical discs, Blu-ray discs, etc.), magnetic disks or other magnetic storage devices, or any other medium capable of carrying or storing desired program code in the form of instructions or data structures and accessible by a computer, but not limited thereto. The memory 403 may exist independently and be connected to the processor 401 via the communication bus 402. The memory 403 may also be integrated with the processor 401.

[0134] The memory 403 stores program code for executing the scheme of this application, and its execution is controlled by the processor 401. The processor 401 executes the program code stored in the memory 403. The program code may include one or more software modules. In the above embodiments, the battery energy optimization scheduling method for new energy vehicles can be implemented by the processor 401 and one or more software modules in the program code in the memory 403.

[0135] Communication interface 404 uses any transceiver-like device to communicate with other devices or communication networks, such as Ethernet, radio access network (RAN), wireless local area networks (WLAN), etc.

[0136] In a specific implementation, as one example, a computer device may include multiple processors, each of which may be a single-core (single-CPU) processor or a multi-core (multi-CPU) processor. Here, a processor may refer to one or more devices, circuits, and / or processing cores used to process data (e.g., computer program instructions).

[0137] The aforementioned computer device can be a general-purpose computer device or a special-purpose computer device. In specific implementations, the computer device can be a desktop computer, a portable computer, a network server, a handheld digital assistant (PDA), a mobile phone, a tablet computer, a wireless terminal device, a communication device, or an embedded device. This application does not limit the type of computer device.

[0138] In addition, this application also provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the above-described battery energy optimization scheduling method for new energy vehicles.

[0139] Although preferred embodiments of this application have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of this application.

[0140] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

Claims

1. A battery energy optimization scheduling method for new energy vehicles, characterized in that, include: During vehicle operation, the instantaneous potential of the positive electrode relative to the reference electrode is determined by a pre-calibrated electrochemical-thermal coupling state estimator based on the battery's terminal voltage, current, and temperature. The safety potential window is determined by the lower and upper critical potentials of irreversible capacity loss, and a boundary approximation zone is preset in the region adjacent to the lower and upper critical potentials within the safety potential window. When the instantaneous potential enters the boundary approach zone, based on the transient response sensitivity of the instantaneous potential to the current, a safe current boundary that does not trigger irreversible capacity loss is determined, and the safe current boundary is reduced by a pre-calibrated upper limit of lifetime loss rate to obtain the loss current limiting boundary. When the instantaneous potential does not exceed the safe potential window, the on-board power converter is controlled to dynamically adjust the charging and discharging power within the power envelope corresponding to the loss current limiting boundary, based on the energy interaction benefit signal of the demand response compensation, so as to maximize the instantaneous energy interaction benefit. When the instantaneous potential exceeds any boundary of the safe potential window, the benefit optimization is terminated, and the charging and discharging power is forcibly reduced to the preset safe power until the instantaneous potential returns to within the safe potential window.

2. The method as described in claim 1, characterized in that, The pre-calibrated electrochemical-thermal coupled state estimator consists of a reduced-order electrochemical model and a closed-loop state observer. The reduced-order electrochemical model characterizes the kinetics of lithium-ion diffusion and interfacial charge transfer reactions in the solid phase of the battery cathode, and its key parameters are corrected by coupling temperature effects through Arrhenius relations. The closed-loop state observer uses the residual between the measured value of the terminal voltage and the model prediction value as feedback to perform online joint estimation of the steady-state potential and polarization potential of the cathode, and outputs the instantaneous potential of the cathode relative to the reference electrode.

3. The method as described in claim 2, characterized in that, Based on the battery's terminal voltage, current, and temperature, the instantaneous potential of the positive electrode relative to the reference electrode is determined using a pre-calibrated electrochemical-thermal coupled state estimator, specifically including: The real-time collected terminal voltage, current and temperature are input into the reduced-order electrochemical model to obtain the prior estimate of the positive electrode potential and the model-predicted terminal voltage. The prior estimate, the real-time acquired terminal voltage, and the model-predicted terminal voltage are input into the closed-loop state observer. The closed-loop state observer is driven by the residual between the measured terminal voltage and the model-predicted terminal voltage to perform closed-loop correction on the estimates of the positive electrode steady-state potential and polarization potential, and outputs the instantaneous potential of the positive electrode relative to the reference electrode.

4. The method as described in claim 1, characterized in that, The safe potential window is determined by the lower and upper critical potentials of irreversible capacity loss, specifically including: By using a reference electrode test, the potential corresponding to lithium plating on the negative electrode was calibrated as the lower critical potential. By using a reference electrode test, the potential corresponding to the irreversible phase transition of the positive electrode active material or the violent oxidative decomposition of the electrolyte is determined as the upper limit critical potential. The open interval between the lower critical potential and the upper critical potential is defined as the safe potential window.

5. The method as described in claim 1, characterized in that, Within the safe potential window, a predefined boundary approximation zone is established in the region adjacent to the lower and upper critical potential limits, specifically including: The lower limit critical potential is floated by a preset voltage bias as the upper boundary of the lower approximation band, and the upper limit critical potential is floated by a preset voltage bias as the lower boundary of the upper approximation band. The region between the lower critical potential and the upper boundary of the lower approximation band, and the region between the lower boundary of the upper approximation band and the upper critical potential, are respectively preset as the lower boundary approximation band and the upper boundary approximation band; The preset voltage bias is dynamically adjusted according to the current lifespan loss rate.

6. The method as described in claim 1, characterized in that, Based on the transient response sensitivity of the instantaneous potential to the current, a safe current boundary that does not trigger irreversible capacity loss is determined, specifically including: Obtain the impedance state quantity generated by the electrochemical-thermal coupled state estimator during the solution of the instantaneous potential, and use the amplitude of the impedance state quantity as the transient response sensitivity of the potential to the current in the current state; The impedance state quantity integrates the contributions of ohmic internal resistance, charge transfer impedance, and diffusion impedance. If the instantaneous potential enters the lower boundary approach zone, the safe current boundary is obtained by dividing the difference between the instantaneous potential and the lower critical potential by the transient response sensitivity. If the instantaneous potential enters the upper boundary approach zone, the safe current boundary is obtained by dividing the difference between the upper critical potential and the instantaneous potential by the transient response sensitivity.

7. The method as described in claim 1, characterized in that, The loss current limiting boundary is obtained by minimizing the safe current boundary using a pre-calibrated upper limit of the lifetime loss rate as a constraint, specifically including: Query the pre-calibrated mapping table between the upper limit of the lifetime wear rate and the current amplitude and the current state of charge to determine the allowable current amplitude that satisfies the upper limit of the lifetime wear rate constraint under the current operating conditions. The amplitude of the safe current boundary is compared with the allowable current amplitude, and the smaller value of the two is selected as the amplitude of the loss current limiting boundary. The direction of the loss current limiting boundary is consistent with the direction of the safe current boundary.

8. The method as described in claim 1, characterized in that, Based on the energy interaction benefit signal of demand response compensation, the on-board power converter is controlled to dynamically adjust the charging and discharging power within the power envelope corresponding to the loss current limiting boundary, so as to maximize the instantaneous energy interaction benefit, specifically including: The system continuously receives real-time feedback of energy loss characteristic indicators from the vehicle drive system and uses these energy loss characteristic indicators as a component of the energy interaction benefit signal. The energy loss characteristic index is constructed based on at least one of the following: the current operating point efficiency of the motor, the switching loss of the inverter, and the power consumption of the high-voltage accessories. The upper and lower limits of allowable charging and discharging power are determined by multiplying the loss current limiting boundary with the current terminal voltage. Within the envelope formed by the upper and lower power limits, with the goal of minimizing the total system loss characterized by the energy loss characteristic index, a local optimization problem is solved to obtain the target charging and discharging power command, which is then sent to the on-board power converter for execution.

9. The method as described in claim 1, characterized in that, When the instantaneous potential exceeds any boundary of the safe potential window, the benefit optimization is terminated, and the charging and discharging power is forcibly reduced to a preset safe power until the instantaneous potential returns to within the safe potential window. Specifically, this includes: When the instantaneous potential is detected to exceed the upper limit critical potential or fall below the lower limit critical potential, the current energy interaction benefit optimization process is immediately terminated. The charging and discharging power is controlled to return to a preset safe power at a preset safe ramp rate, wherein the preset safe power is zero power or trickle power to maintain the vehicle's basic load; The instantaneous potential is continuously monitored. Once it is confirmed that the potential has stably fallen back to within the safe potential window and entered the region outside the boundary approach zone, the benefit optimization process is re-enabled after a preset delay.

10. A battery energy optimization scheduling system for new energy vehicles, characterized in that, include: The potential estimation module is used to determine the instantaneous potential of the positive electrode relative to the reference electrode during vehicle operation, based on the battery's terminal voltage, current, and temperature, through a pre-calibrated electrochemical-thermal coupling state estimator. The window setting module is used to determine the safe potential window based on the lower and upper critical potentials of irreversible capacity loss, and to preset a boundary approximation zone in the region adjacent to the lower and upper critical potentials within the safe potential window. The current limiting decision module is used to determine a safe current boundary that does not trigger irreversible capacity loss based on the transient response sensitivity of the instantaneous potential to the current when the instantaneous potential enters the boundary approach zone, and to reduce the safe current boundary by taking a pre-calibrated upper limit of the lifetime loss rate as a constraint to obtain the loss current limiting boundary. The optimization scheduling module is used to control the on-board power converter to dynamically adjust the charging and discharging power within the power envelope corresponding to the loss current limiting boundary, based on the energy interaction benefit signal of the demand response compensation when the instantaneous potential does not exceed the safe potential window, so as to maximize the instantaneous energy interaction benefit. The over-limit protection module is used to exit the benefit optimization when the instantaneous potential exceeds any boundary of the safe potential window, and to forcibly reduce the charging and discharging power to a preset safe power until the instantaneous potential returns to within the safe potential window.

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