CN-122001056-A - Battery charge and discharge control method and system based on internal health state

CN122001056ACN 122001056 ACN122001056 ACN 122001056ACN-122001056-A

Abstract

The invention discloses a battery charge and discharge control method and system based on an internal health state, comprising the steps of inputting a control quantity at the current moment, an external measurable parameter and an internal health state estimation vector at the last moment into a state space model, obtaining an estimated change rate predicted value of the internal health state at the current moment and an external measurable predicted value at the current moment through processing the control quantity and the internal health state estimation vector, and outputting the internal health state estimation vector at the current moment by combining the external measurable parameter; and adjusting the actual charge and discharge current based on the target control quantity and taking the actual charge and discharge current as the control quantity at the next moment until the charge and discharge termination condition is reached. The invention can accurately sense the internal health state of the battery and realize active closed-loop control based on the internal health state.

Inventors

HAN WENJIE
MAO HENGSHAN
LIU XIAOJIE
HU WEIHAO
LIU HAOJI
WANG JIE
LI WEI
WANG TAO
LIU JUN

Assignees

中电建新能源集团股份有限公司

Dates

Publication Date: 20260508
Application Date: 20251230

Claims (11)

1. A battery charge and discharge control method based on an internal state of health, comprising: Inputting the control quantity of the battery pack at the current moment, the external measurable parameters and the internal health state estimation vector at the last moment into a state space model, obtaining an estimated change rate predicted value of the internal health state at the current moment and an external measurable predicted value at the current moment by processing the control quantity at the current moment and the internal health state estimation vector at the last moment, and outputting the internal health state estimation vector at the current moment by combining the external measurable parameters; Constructing an objective function by maximizing the control quantity at the current moment, constructing constraint conditions based on the internal health state estimation vector at the current moment, and solving the objective function under the condition that the constraint conditions are met to obtain the target control quantity at the current moment; And adjusting the actual charge and discharge current actually applied to the battery pack based on the target control quantity, and taking the target control quantity as the control quantity of the next moment to form a closed-loop control loop until the charge and discharge termination condition is reached.
2. The method of claim 1, wherein the control quantity comprises a charge-discharge current, the externally measurable parameters comprise at least a terminal voltage and a surface temperature, and the internal state of health estimation vector comprises at least a state of charge, a state of health, an internal core temperature, an electrode lithium evolution rate, a solid electrolyte interfacial film growth rate.
3. The method according to claim 1, characterized in that the state space model consists of a state equation, an observation equation and a gain matrix, and in that the state space model outputs the internal health state estimation vector at the current moment, respectively, by: processing the control quantity at the current moment and the internal health state estimation vector at the last moment by the state equation and the observation equation, and respectively outputting an estimated change rate predicted value of the internal health state at the current moment and a predicted value which can be measured outside the current moment; And outputting the estimated vector of the internal health state at the current moment according to the predicted value of the estimated change rate of the internal health state at the current moment, the predicted value which can be measured outside the current moment, the external measurable parameter at the current moment, the estimated vector of the internal health state at the last moment and the gain matrix.
4. A method according to claim 3, wherein said outputting an internal state of health estimation vector at the current time based on the estimated rate of change prediction value of the internal state of health at the current time, the externally measurable prediction value at the current time, the externally measurable parameter at the current time, the internal state of health estimation vector at the last time, and the gain matrix comprises: calculating an error value of the external measurable parameter at the current moment and the predicted value which is measurable outside the current moment, and carrying out weighting processing on the error value by combining the gain matrix to obtain a state correction term; Adding the predicted value of the estimated change rate of the internal health state at the current moment to the state correction term to obtain the corrected estimated change rate of the internal health state at the current moment; And carrying out integral operation on the corrected internal health state estimation change rate at the current moment, adding an integral result to the internal health state estimation vector at the previous moment to obtain and output the internal health state estimation vector at the current moment.
5. The method according to claim 1, wherein the constraints comprise at least: The estimated internal core temperature at the current moment does not exceed a preset temperature safety threshold, the estimated lithium precipitation rate of the electrode at the current moment does not exceed a preset lithium precipitation rate safety threshold, and the estimated health state decay rate at the current moment does not exceed a preset decay rate safety threshold.
6. The method according to claim 1, wherein the adjusting the actual charge-discharge current actually applied to the battery pack based on the target control amount includes: Generating an optimal charge-discharge instruction at the current moment based on the target control quantity, sending the optimal charge-discharge instruction to a charge-discharge execution module, and enabling the deviation between the actual charge-discharge current output by the charge-discharge execution module and the target control quantity to be in a preset precision range by adjusting the hardware working parameters of the charge-discharge execution module.
7. The method of claim 1, wherein the closed loop control comprises: And acquiring external measurable parameters of the battery pack at corresponding moments in real time, wherein the external measurable parameters are used for inputting the state space model to update the internal health state estimation vector until a charge and discharge termination condition is reached, and stopping charge and discharge control, and the charge and discharge termination condition comprises that the charge state of the battery pack reaches 100%, the charge state reaches 0% or an external shutdown instruction is received.
8. A battery charge and discharge control system based on an internal state of health, comprising: The health state observer module is internally provided with a state space model, and is used for inputting the control quantity of the battery pack at the current moment, the external measurable parameters and the internal health state estimation vector at the last moment into the state space model, obtaining the estimated change rate predicted value of the internal health state at the current moment and the external measurable predicted value at the current moment by processing the control quantity at the current moment and the internal health state estimation vector at the last moment, and outputting the internal health state estimation vector at the current moment by combining the external measurable parameters; The charge-discharge control module is used for constructing an objective function by maximizing the control quantity at the current moment, constructing constraint conditions based on the internal health state estimation vector at the current moment, and solving the objective function under the condition that the constraint conditions are met to obtain the objective control quantity at the current moment; And the charge and discharge execution module is used for adjusting the actual charge and discharge current actually applied to the battery pack based on the target control quantity, and taking the target control quantity as the control quantity at the next moment to form a closed-loop control loop until the charge and discharge termination condition is reached.
9. An electronic device, comprising: A memory and a processor in communication with each other, the memory having stored therein computer instructions which, upon execution, cause the processor to perform the steps of the method of any of claims 1 to 7.
10. A computer storage medium storing computer program instructions which, when executed, implement the steps of the method of any one of claims 1 to 7.
11. A computer program product comprising a computer program which, when executed by a processor, implements the steps of the method of any one of claims 1 to 7.

Description

Battery charge and discharge control method and system based on internal health state Technical Field The present invention relates to the field of battery management technologies, and in particular, to a battery charge and discharge control method and system based on an internal health state. Background The balance of the safety, the charging efficiency and the service life of the lithium battery energy storage system is the core requirement of large-scale application, and the charging and discharging control strategy directly determines the performance index. However, the existing battery charge-discharge control method has two major core problems, namely, the mainstream constant-current constant-voltage charge-discharge method adopts open-loop control, the battery is regarded as a 'black box', a fixed control strategy is formulated only by depending on external measurable parameters, the internal health state of the battery cannot be perceived, the contradiction between the battery charge efficiency and health (the charge is limited when the battery state is good and the aging is accelerated when the charge speed is pursued) is caused, the traditional PID and other control algorithms are sensitive to measurement noise, the internal health state of the battery cannot be accurately obtained, the battery can only be passively controlled based on noisy external parameters, and the control precision and the robustness are insufficient. In view of the above problems, no effective solution has been proposed at present. Disclosure of Invention The embodiment of the specification provides a battery charge and discharge control method and system based on an internal health state, which are used for solving the problems that the internal health state of a battery cannot be accurately perceived in the prior art, the battery is easy to be interfered by noise, and active closed-loop control based on the internal health state is difficult to realize. In a first aspect, embodiments of the present disclosure provide a battery charge and discharge control method based on an internal health state, including: Inputting the control quantity of the battery pack at the current moment, the external measurable parameters and the internal health state estimation vector at the last moment into a state space model, obtaining an estimated change rate predicted value of the internal health state at the current moment and an external measurable predicted value at the current moment by processing the control quantity at the current moment and the internal health state estimation vector at the last moment, and outputting the internal health state estimation vector at the current moment by combining the external measurable parameters; Constructing an objective function by maximizing the control quantity at the current moment, constructing constraint conditions based on the internal health state estimation vector at the current moment, and solving the objective function under the condition that the constraint conditions are met to obtain the target control quantity at the current moment; And adjusting the actual charge and discharge current actually applied to the battery pack based on the target control quantity, and taking the target control quantity as the control quantity of the next moment to form a closed-loop control loop until the charge and discharge termination condition is reached. In some embodiments, the control amount includes a charge-discharge current, the external measurable parameters include at least a terminal voltage and a surface temperature, and the internal state of health estimation vector includes at least a state of charge, a state of health, an internal core temperature, an electrode lithium precipitation rate, a solid electrolyte interfacial film growth rate. In some embodiments, the state space model is composed of a state equation, an observation equation, and a gain matrix, and accordingly, the state space model outputs an internal health state estimation vector at the current time by: processing the control quantity at the current moment and the internal health state estimation vector at the last moment by the state equation and the observation equation, and respectively outputting an estimated change rate predicted value of the internal health state at the current moment and a predicted value which can be measured outside the current moment; And outputting the estimated vector of the internal health state at the current moment according to the predicted value of the estimated change rate of the internal health state at the current moment, the predicted value which can be measured outside the current moment, the external measurable parameter at the current moment, the estimated vector of the internal health state at the last moment and the gain matrix. In some embodiments, the outputting the estimated internal health state vector at the current time according to the estimated change rate predicted value of