JP6605938B2 - Secondary battery control device, control method, and control program - Google Patents

Description

  The present invention relates to a control device, control method, and control program for a secondary battery, and more particularly, a control device, control method, and control for a secondary battery that calculates a discharge power allowable amount indicating an allowable amount of power that can be discharged from the secondary battery. Regarding the program.

  In recent years, the use of secondary batteries has also expanded in automobiles and the like. The secondary battery has a memory effect that power that can be output is reduced by repeating charge and discharge. Therefore, when using a secondary battery, it is necessary to determine the magnitude of electric power that can be output (hereinafter, discharge power allowable value) in consideration of the memory effect. Therefore, Patent Document 1 discloses a technique for estimating a change in output characteristics of a secondary battery due to a memory effect.

  In the method for controlling an electrochemical element described in Patent Document 1, the state of an electrochemical element including an electrode and an ionic conductor is changed to an electrode potential model, an electrode electron transport model, an electrode ion transport model, and an ion conductor. Analysis using at least one model selected from the group consisting of an ion transport model and a model representing an electrochemical reaction that occurs at the interface between an electrode and an ionic conductor. Control properties.

Japanese Patent Laid-Open No. 2000-1000047

  Here, a decrease in the output voltage of the secondary battery due to the memory effect will be described. FIG. 5 is a graph showing the change in output voltage with respect to the charging rate, explaining the memory effect in the secondary battery. As shown in FIG. 5, the output voltage of the secondary battery changes as the charging rate changes. The secondary battery has a discharge power allowable value Wout1 corresponding to the difference between the output voltage curve at the time of shipment (two-dot chain line in FIG. 5) and the lower limit output voltage at the time of shipment. However, when the influence of the memory effect appears on the secondary battery, the output voltage below a certain charging rate is lower than the output voltage at the time of shipment. Therefore, after the memory effect appears, the discharge power allowable value Wout2 of the secondary battery becomes a difference between the output voltage curve indicated by the solid line and the lower limit output voltage.

  However, the magnitude of the voltage drop due to the memory effect of the secondary battery or the charging rate at which the voltage drop occurs varies depending on the usage state of the secondary battery, such as the number of charge / discharge cycles and the charge / discharge start voltage. Therefore, even if the memory effect is analyzed using the technique described in Patent Document 1, the discharge power allowable power must be set in accordance with the worst condition obtained from the analysis result. In FIG. 5, the output voltage curve of the secondary battery in accordance with the worst condition of the voltage drop due to the memory effect is shown by a one-dot chain line. In the example illustrated in FIG. 5, the dischargeable allowable power Wout3 is a difference between the output voltage of the secondary battery and the lower limit output voltage in accordance with the worst condition. That is, when the memory effect estimation method described in Patent Document 1 is used, the discharge power allowable value Wout2 that should be output originally cannot be output, and the discharge power allowable value in which the discharge power allowable value is excessively limited. Must be Wout3.

  As described above, although the technique described in Patent Document 1 can analyze the performance deterioration of the secondary battery in advance, there is a problem that the secondary battery cannot be controlled in accordance with the current state of the secondary battery.

  The present invention has been made in view of the above circumstances, and an object thereof is to perform control in accordance with the current performance of a secondary battery.

  One aspect of a control apparatus for a secondary battery according to the present invention is a control apparatus for a secondary battery that controls electric power output from the secondary battery, and indicates a magnitude of a current discharged from the secondary battery. A battery voltage estimator that calculates a voltage estimated value obtained by estimating a voltage of the secondary battery based on a battery voltage model having a battery current value and temperature information indicating a temperature of the secondary battery as parameters; and the secondary battery A voltage error calculation unit that calculates a difference between a voltage measurement value that is a measurement value of a battery voltage and the voltage estimation value as a voltage error measurement value, and a charging rate that estimates a charging rate of the secondary battery based on the battery current value A battery voltage for calculating a voltage error estimated value indicating an error of the battery voltage generated due to the memory effect of the secondary battery, using an estimation unit and a voltage error model having the charging rate and the correction value as parameters. An error estimator and the voltage error Anda correction value calculation unit difference between the voltage error estimate and the measured value to calculate the correction value to be smaller, performs control of the secondary battery based on the correction value.

  According to the aspect of the secondary battery control device according to the present invention, the secondary battery can be controlled based on the correction value calculated from the current state of the secondary battery.

  In another aspect of the control device for a secondary battery according to the present invention, the correction value is higher than a memory effect generation charge rate indicating a charge rate at which the memory effect is generated, and the memory effect generation charge rate. A rising fluctuation voltage indicating a voltage increase amount of the secondary battery generated at a charging rate, and a falling fluctuation voltage indicating a voltage decrease amount of the secondary battery generated at a charging rate lower than the memory effect generation charging rate; , At least.

  According to the first aspect of the secondary battery control device of the present invention, the output voltage curve resulting from the memory effect currently occurring in the secondary battery is estimated, and the performance of the current secondary battery is grasped. can do.

  According to a second aspect of the control apparatus for a secondary battery according to the present invention, a battery voltage estimation curve is obtained by applying the correction value to a fluctuation curve of an initial electromotive voltage of the secondary battery with respect to the charging rate. Calculate and output the difference between the lower limit output voltage preset for the secondary battery and the battery voltage estimation curve as a discharge power allowable value indicating an allowable amount of power that can be discharged from the secondary battery. And a discharge power allowance calculation unit.

  According to the second another aspect of the control device for the secondary battery according to the present invention, the secondary battery control device is adapted to the current state of the secondary battery based on the battery voltage estimation curve estimated based on the parameter obtained from the secondary battery. An allowable discharge power value can be obtained.

  According to a third aspect of the control apparatus for a secondary battery according to the present invention, the voltage error model is calculated based on a memory effect error model using the charge rate and the correction value as parameters. And a current sensor offset error estimated value indicating an error caused by a current sensor that measures a current discharged from the secondary battery.

  A fourth alternative embodiment of the control apparatus for a secondary battery according to the present invention is a battery current calculation for calculating the battery current value by subtracting the current sensor offset error estimated value from the current measurement value output by the current sensor. It further has a part.

  According to the third and fourth aspects of the control apparatus for a secondary battery according to the present invention, it is possible to obtain a highly accurate correction value in which the influence of the offset error of the current sensor is reduced.

  One aspect of the control method of the secondary battery according to the present invention shows the temperature of the secondary battery, the voltage measurement value indicating the voltage output from the secondary battery, and the magnitude of the current output from the secondary battery. Obtaining a current measurement value, calculating a correction value by estimating a fluctuation amount of the output voltage of the secondary battery based on the temperature, the voltage measurement value, and the current measurement value, and based on the correction value A secondary battery control method for controlling power output from a secondary battery, wherein a battery current value indicating a magnitude of a current discharged from the secondary battery and temperature information indicating a temperature of the secondary battery. And calculating a voltage estimated value obtained by estimating the voltage of the secondary battery based on a battery voltage model using as a parameter, calculating a difference between the voltage measured value and the voltage estimated value as a voltage error measured value, The charging rate of the secondary battery based on the current value And using a voltage error model having the charging rate and the correction value as parameters, a voltage error estimated value indicating an error in the battery voltage caused by a characteristic variation of the secondary battery is calculated, and the voltage The correction value is calculated so that the difference between the error measurement value and the voltage error estimation value is small, and the secondary battery is controlled based on the correction value.

  According to the aspect of the secondary battery control method according to the present invention, the secondary battery can be controlled based on the correction value calculated from the current state of the secondary battery.

  One aspect of a control program for a secondary battery according to the present invention is executed by an arithmetic unit capable of executing the program, and a voltage measurement value indicating a temperature of the secondary battery, a voltage output by the secondary battery, and the second A correction value is obtained by obtaining a current measurement value indicating the magnitude of the current output from the secondary battery, and estimating a variation amount of the output voltage of the secondary battery based on the temperature, the voltage measurement value, and the current measurement value. And a secondary battery control program for controlling the power output from the secondary battery based on the correction value, the battery current value indicating the magnitude of the current discharged from the secondary battery; A voltage estimated value obtained by estimating the voltage of the secondary battery based on a battery voltage model having a temperature information indicating the temperature of the secondary battery as a parameter, and a difference between the measured voltage value and the estimated voltage value The voltage error measurement value and Generated by estimating the charge rate of the secondary battery based on the battery current value and using the voltage error model with the charge rate and the correction value as parameters. A voltage error estimated value indicating an error in battery voltage to be calculated, the correction value is calculated so that a difference between the voltage error measured value and the voltage error estimated value is small, and the secondary battery is based on the correction value. Control.

  According to one aspect of the control program for a secondary battery according to the present invention, the secondary battery can be controlled based on the correction value calculated from the current state of the secondary battery.

  According to the secondary battery control device, control method, and control program of the present invention, it becomes possible to control the secondary battery in accordance with the current performance of the secondary battery.

1 is a block diagram of a control device according to a first exemplary embodiment. 6 is a graph for explaining a voltage estimation model used for calculation of a model error value in the control device according to the first embodiment; 5 is a flowchart for explaining a correction value calculation procedure in the control apparatus according to the first embodiment; It is a figure explaining the electromotive force curve estimated from a correction value in the control apparatus concerning Embodiment 1. FIG. It is a graph which shows the change of the output voltage with respect to the charging rate explaining the memory effect in a secondary battery.

  In order to clarify the explanation, the following description and drawings are omitted and simplified as appropriate. Each element described in the drawings as a functional block for performing various processes can be configured by a CPU, a memory, and other circuits in terms of hardware, and a program loaded in the memory in terms of software. Etc. Therefore, it is understood by those skilled in the art that these functional blocks can be realized in various forms by hardware only, software only, or a combination thereof, and is not limited to any one. In the drawings, the same elements are denoted by the same reference numerals, and redundant description is omitted as necessary.

  Further, the above-described program can be stored using various types of non-transitory computer readable media and supplied to a computer. Non-transitory computer readable media include various types of tangible storage media. Examples of non-transitory computer-readable media include magnetic recording media (for example, flexible disks, magnetic tapes, hard disk drives), magneto-optical recording media (for example, magneto-optical disks), CD-ROM (Read Only Memory) CD-R, CD -R / W, semiconductor memory (for example, mask ROM, PROM (Programmable ROM), EPROM (Erasable PROM), flash ROM, RAM (Random Access Memory)). The program may also be supplied to the computer by various types of transitory computer readable media. Examples of transitory computer readable media include electrical signals, optical signals, and electromagnetic waves. The temporary computer-readable medium can supply the program to the computer via a wired communication path such as an electric wire and an optical fiber, or a wireless communication path.

Embodiment 1
The control device 1 according to the first embodiment controls the power output from the secondary battery based on the output voltage, output current, and temperature of the secondary battery. Moreover, the control apparatus 1 concerning Embodiment 1 is implement | achieved by the program run in arithmetic units, such as a microcontroller, for example. The microcontroller also has an analog-to-digital conversion circuit that takes in an analog value parameter such as a voltage used in arithmetic processing as a digital value. Furthermore, the microcontroller has an output interface or a communication interface that outputs a control parameter (in the following example, allowable discharge power value Wout) of the secondary battery obtained by calculation to a higher system. In the following description, the control device 1 will be described using a block diagram in which processing in a program is replaced with processing blocks for each type of processing.

  In the following description, the control device 1 according to the first embodiment, as an example of the control performed by the control device 1, is an allowable discharge power value in consideration of a decrease in output voltage due to the memory effect of the secondary battery. An example of performing control of the secondary battery corresponding to the change of will be described. Moreover, the control apparatus 1 concerning Embodiment 1 performs the calculation based on an extended Kalman filter in order to respond | correspond to the nonlinearity of a secondary battery. In addition, since the control apparatus 1 concerning Embodiment 1 controls a secondary battery in consideration of a memory effect, it is suitable for a secondary battery (for example, nickel hydride storage battery) with a large influence of a memory effect.

  FIG. 1 shows a block diagram of a control device 1 according to the first embodiment. As shown in FIG. 1, the control device 1 according to the first embodiment includes a battery current calculation unit 11, a battery voltage estimation unit 12, a voltage error calculation unit 13, an observation error calculation unit 14, a correction value calculation unit 15, and a battery voltage. An error estimation unit 16, a discharge power allowable value calculation unit 17, and a charge rate estimation unit 18 are included.

The battery current calculation unit 11 calculates the battery current value by subtracting the current sensor offset error estimated value δcur _offset from the current measurement value output by the current sensor (not shown). In the example illustrated in FIG. 1, the battery current calculation unit 11 calculates the battery current value by subtracting the current sensor offset error estimated value δcur _offset from the current measurement value.

  The battery voltage estimation unit 12 uses a battery voltage model that uses as parameters the battery current value indicating the magnitude of the current discharged from the secondary battery and the temperature information (for example, temperature measurement value) indicating the temperature of the secondary battery. A voltage estimated value obtained by estimating the voltage of the secondary battery is calculated based on Here, the battery voltage model is an electrode potential model, an electrode electron transport model, an electrode ion transport model, an ion transport ion transport model, and a model representing an electrochemical reaction occurring at the interface between the electrode and the ion conductor. Including at least one model selected from the group consisting of:

  The voltage error calculation unit 13 calculates a difference between a voltage measurement value that is a measurement value of the voltage of the secondary battery and a voltage estimation value output from the voltage error calculation unit 13 as a voltage error measurement value y. In the example illustrated in FIG. 1, the voltage error calculation unit 13 calculates the voltage error measurement value y by subtracting the voltage estimation value from the voltage measurement value.

  The observation error calculation unit 14 calculates a difference between the voltage error measurement value y output from the voltage error calculation unit 13 and the voltage error estimation value z output from the battery voltage error estimation unit 16 as an observation error value. In the example illustrated in FIG. 1, the observation error calculation unit 14 calculates the observation error value by subtracting the voltage error estimated value z from the voltage error measurement value y.

The correction value calculation unit 15 calculates the correction value so that the difference (observation error value) between the voltage error measurement value y and the voltage error estimated value z becomes small. In the control device 1 according to the first embodiment, the correction value is generated when the memory effect generation charge rate SOC _memory indicating the charge rate at which the memory effect occurs and the charge rate higher than the memory effect occurrence charge rate SOC _memory. It includes at least a rising fluctuation voltage δv _up indicating a voltage increase amount of the secondary battery, and a falling fluctuation voltage δv _down indicating a voltage drop amount of the secondary battery generated when the charging rate is lower than the memory effect generation charging rate. The correction value used in the control device 1 according to the first embodiment includes a current sensor offset error estimated value δcur _offset indicating an error caused by the current sensor that measures the current discharged from the secondary battery.

The battery voltage error estimator 16 calculates a voltage error estimated value z indicating a battery voltage error generated due to the memory effect of the secondary battery, using a voltage error model having the charging rate and the correction value as parameters. To do. Here, the voltage error model V _{err, mdl} is expressed by the equation (1), and a value calculated based on the equation (1) is the voltage error estimated value z.

In this equation (1), R _dc is the DC resistance of the secondary battery, and the product term of the DC resistance Rdc and the current sensor offset error estimated value δcur _offset is the current sensor offset voltage value. In addition, the term of δV _{mdl in} the expression (1) is a model error value. This model error value δV _mdl is calculated based on the voltage estimation model. FIG. 2 shows a graph for explaining a voltage estimation model used for calculation of a model error value in the control apparatus according to the first embodiment.

As shown in FIG. 2, the voltage estimation model, the charging rate SOC of the horizontal axis, and the vertical axis represents the output voltage variation, rising varying voltage .delta.v _{Stay up-,} falling varying voltage .delta.v _down and three memory effect occurs _{the SOC memory} It is a graph which has a parameter. In addition, the voltage estimation model has ΔSOC as a fixed value indicating the magnitude of the range of the charging rate SOC in which the voltage change amount switches from positive to negative with the memory effect generation charging rate SOC _memory as a center. Then, the battery voltage error estimation unit 16 inputs the SOC estimation value output from the charging rate estimation unit 18 to the voltage estimation model, and calculates the output voltage change amount corresponding to the SOC estimation value input in the graph of FIG. Calculated as a model error value ΔV _mdl .

In the control device 1 according to the first embodiment, the correction value calculation unit 15 changes the four parameters included in the correction value, thereby changing the voltage error estimated value z output from the correction value calculation unit 15. Then, in the control device 1 according to the first embodiment, two parameters are used based on the correction value parameter when it is determined that the observation error value that is the difference between the voltage error observation value y and the voltage error estimation value z is sufficiently small. Control the next battery. Specifically, among the parameters included in the correction value, the discharge power allowable value Wout is set to the vehicle that is the host system of the control device 1 based on the rising fluctuation voltage δv _up , the falling fluctuation voltage δv _down and the memory effect occurrence charging rate SOC _memory. Output. Further, the battery current value is calculated based on the current sensor offset error estimated value δcur _offset included in the correction value.

Discharge power allowable value calculation unit 17 applies a correction value (for example, a voltage estimation parameter included in the correction value) to a variation curve of an initial electromotive voltage of the secondary battery with respect to the charging rate SOC, and calculates a battery voltage estimation curve. calculate. The voltage estimation parameters include a rising fluctuation voltage δv _up , a falling fluctuation voltage δv _down, and a memory effect generation charge rate SOC _memory . In addition, the discharge power allowable value calculation unit 17 calculates the allowable amount of power that can be discharged from the secondary battery by calculating the difference between the lower limit output voltage that is preset for the secondary battery and the calculated battery voltage estimation curve. It outputs as the discharge power allowable value Wout shown. This discharge power allowable value Wout is transmitted to the vehicle that is the host system of the control device 1. The vehicle adjusts the magnitude of power discharged from the secondary battery based on the received discharge power allowable amount Wout.

  The charging rate estimation unit 18 estimates the charging rate SOC of the secondary battery based on the battery current value output by the battery current calculation unit 11. More specifically, the charging rate estimation unit 18 calculates the charging rate SOC based on the integrated value generated by the integrating process that integrates the battery current value. The calculated charging rate SOC is output to the battery voltage error estimating unit 16 as an SOC estimated value. The estimated SOC value is also output to a vehicle that is a host system.

  Next, a memory effect estimation procedure in the control device 1 according to the first embodiment will be described. FIG. 3 is a flowchart for explaining a correction value calculation procedure in the control device 1 according to the first embodiment. In the control device 1 according to the first embodiment, the flow shown in FIG. 3 is repeatedly executed until the difference between the voltage error measurement value y and the voltage error estimated value z becomes sufficiently small. 3 is a process performed by the correction value calculation unit 15 and the battery voltage error estimation unit 16.

In FIG. 3, equations used in each process are shown. In the equation, k is an integer indicating the number of a calculation cycle in one process period for calculating one correction value. “+” Added to the upper right of the letter indicates that the value is a newly calculated value in the kth calculation cycle, and “−” is calculated in the calculation cycle before the kth. Indicates that the old value was set. The hat symbol added on the character indicates that the value indicated by the character is an estimated value. In FIG. 3, the correction value is represented by x. This x is a transposed matrix including the above-described four parameters, and is expressed by equation (2).

  As shown in FIG. 3, in the control device 1 according to the first embodiment, the correction value calculation process for correcting the change in the output voltage due to the memory effect is performed by the processes in steps S <b> 1 to S <b> 4.

In step S1, the estimated value (for example, correction value) calculated in the previous calculation cycle is linearized. The linearization process in step S1 is performed based on the equation (3), and the matrix _Ad is obtained by the linearization process.

In step S2, an estimated value time update process is performed. This is a process for making the value calculated in the previous calculation cycle a past value in the current calculation cycle. This time update process is performed based on the equations (4) to (6).

  In equation (4), the correction value x calculated in the previous calculation cycle is substituted into the function f (x) to obtain the old correction value in the current calculation cycle. In equation (5), the correction value x of the previous calculation cycle calculated in equation (4) is substituted into the function h (x) to obtain the voltage error estimated value z in the current calculation cycle. In equation (6), the old covariance matrix P in the current calculation cycle is obtained based on the covariance matrix P calculated in the previous calculation cycle. Note that Q in the equation (6) is a process noise covariance matrix indicating a deviation between the voltage error model and the actual characteristics of the secondary battery.

In step S3, the correction value x input in the current calculation cycle is linearized. In the linearization process in step S3, the matrix C is calculated based on the equation (7).

In step S4, the observed value time update process is performed. This is a process for holding the value calculated in the current calculation cycle as the latest value. This time update process is performed based on the equations (8) to (10). Note that K calculated by equation (8) is a Kalman gain, R in equation (8) is a covariance matrix of observation noise, and I in equation (9) is a unit matrix. In the equation (10), y is a voltage error measurement value, and z is a voltage error estimation value.

  In the control device 1 according to the first embodiment, the discharge power allowable value Wout is calculated based on the correction value calculated by the procedure as described above. More specifically, in the control device 1 according to the first embodiment, the estimated electromotive force curve in which the discharge power allowable value calculating unit 17 corrects the electromotive voltage curve (initial electromotive voltage curve) based on the calculated correction value. Is generated. FIG. 4 is a diagram for explaining a battery voltage estimation curve (for example, an estimated electromotive voltage curve) estimated from the correction value in the control device according to the first embodiment.

  As shown in FIG. 4, the estimated electromotive force curve generated by the control device 1 according to the first embodiment has a voltage lower than the initial electromotive voltage in a region where the charging rate SOC is low due to the memory effect. In the control device 1 according to the first embodiment, the allowable discharge power calculation unit 17 outputs the difference between the estimator voltage curve and the preset lower limit output voltage as the allowable discharge power value Wout.

  From the above description, in the control device 1 according to the first embodiment, the voltage error observation value calculated based on the voltage measurement value, the current measurement value, and the temperature measurement value acquired from the current secondary battery, the charging rate, and the correction value are calculated. The value of the correction value is obtained so that there is no difference between the estimated voltage error value calculated using the voltage error model using as a parameter. And the estimated electromotive force curve which considered the influence of the memory effect which has generate | occur | produced in the present secondary battery is produced | generated by correcting the initial electromotive voltage using the said correction value. Then, the control device 1 according to the first embodiment outputs the difference between the estimated electromotive voltage curve and the preset lower limit output voltage as the discharge power allowable value Wout. That is, by using the control device 1 according to the first embodiment, it is possible to output the discharge power allowable value Wout that dynamically changes in consideration of the influence of the memory effect based on the current state of the secondary battery.

  As a result, the control device 1 according to the first embodiment takes into consideration the influence of the variation even when the deterioration degree of the voltage output characteristic due to the memory effect of the secondary battery varies based on the difference in the usage state. The allowable discharge power value Wout according to the performance of the secondary battery can be output without taking the margin or reducing the margin. The secondary battery controlled by the control device 1 according to the first embodiment substantially improves the output performance by reducing the margin in consideration of the variation in the performance degradation caused by the memory effect. be able to. Moreover, since the power that can be taken out from the secondary battery is increased by reducing the margin in consideration of the variation in performance deterioration, the secondary battery is used for the purpose of supplying power to the drive motor of the automobile. In some cases, the fuel consumption of the car can be increased.

  In the above description, the control device 1 according to the first embodiment is used to calculate the allowable discharge power value Wout in consideration of the influence of the memory effect. However, the control device 1 has a value other than the allowable discharge power value Wout. However, it is possible to calculate a characteristic value that varies due to the memory effect. Therefore, you may use the control apparatus 1 for calculation of characteristic values other than discharge power allowable value Wout, and control of a secondary battery based on the said characteristic value.

In the control device 1 according to the first embodiment, the correction value includes the current sensor offset error estimated value δcur _offset . Thereby, the control apparatus 1 concerning Embodiment 1 can calculate the battery electric current value reflecting the detection error of the current sensor according to the present condition. That is, the control device 1 according to the first embodiment can increase the accuracy of the battery current value. Thereby, the control apparatus 1 concerning Embodiment 1 raises the precision of the estimated voltage value which the battery voltage estimation part 12 calculates, and the SOC estimated value which the charge rate estimation part 18 calculates, and the value obtained as a result Overall accuracy can be increased.

  Note that the present invention is not limited to the above-described embodiment, and can be changed as appropriate without departing from the spirit of the present invention.

DESCRIPTION OF SYMBOLS 1 Control apparatus 11 Battery current calculation part 12 Battery voltage estimation part 13 Voltage error calculation part 14 Observation error calculation part 15 Correction value calculation part 16 Battery voltage error estimation part 17 Discharge electric power allowable value calculation part 18 Charging rate estimation part

Claims (5)

A control device for a secondary battery that controls electric power output from the secondary battery,
A voltage obtained by estimating the voltage of the secondary battery based on a battery voltage model having as parameters the battery current value indicating the magnitude of the current discharged from the secondary battery and the temperature information indicating the temperature of the secondary battery. A battery voltage estimator for calculating an estimated value;
A voltage error calculation unit that calculates a difference between a voltage measurement value that is a measurement value of the voltage of the secondary battery and the voltage estimation value as a voltage error measurement value;
A charge rate estimator for estimating a charge rate of a secondary battery based on the battery current value;
A battery voltage error estimator for calculating a voltage error estimated value indicating an error in the battery voltage generated due to the memory effect of the secondary battery using a voltage error model having the charging rate and the correction value as parameters; ,
A correction value calculation unit that calculates the correction value so that a difference between the voltage error measurement value and the voltage error estimation value is small;
A battery voltage estimation curve is calculated by applying the correction value to a fluctuation curve of an initial electromotive voltage of the secondary battery with respect to the charging rate, and a lower limit output voltage set in advance for the secondary battery; A discharge power allowable amount calculation unit that outputs a difference between the battery voltage estimation curve and a discharge power allowable value indicating an allowable amount of electric power that can be discharged from the secondary battery ;
The correction value includes a memory effect generation charge rate indicating a charge rate at which the memory effect occurs, and a rising fluctuation voltage indicating a voltage increase amount of the secondary battery generated at a charge rate higher than the memory effect generation charge rate. And a falling fluctuation voltage indicating a voltage drop amount of the secondary battery generated at a charging rate lower than the memory effect generating charging rate,
The voltage error model includes a charge rate change range indicating a range of a charge rate in which the voltage change amount is switched from positive to negative as a fixed value, with the memory effect generation charge rate being the center of the range, and a control device for a secondary battery . The voltage error model is based on a model error value using the charging rate and the correction value as parameters, and a current sensor offset error estimated value indicating an error caused by a current sensor that measures a current discharged from the secondary battery. The secondary battery control device according to claim 1 , further comprising: a calculated current sensor offset voltage value. The secondary battery control device according to claim 2 , further comprising a battery current calculation unit that calculates the battery current value by subtracting the current sensor offset error estimated value from the current measurement value output by the current sensor. Obtaining the temperature of the secondary battery, the voltage measurement value indicating the voltage output from the secondary battery, and the current measurement value indicating the magnitude of the current output from the secondary battery, the temperature and the voltage measurement value And calculating a correction value by estimating a variation amount of the output voltage of the secondary battery based on the current measurement value, and controlling a power output from the secondary battery based on the correction value. A control method,
A voltage obtained by estimating the voltage of the secondary battery based on a battery voltage model having as parameters the battery current value indicating the magnitude of the current discharged from the secondary battery and the temperature information indicating the temperature of the secondary battery. Calculate an estimate,
The difference between the voltage measurement value and the voltage estimation value is calculated as a voltage error measurement value,
Estimating the charging rate of the secondary battery based on the battery current value,
Using a voltage error model with the charging rate and the correction value as parameters, a voltage error estimation value indicating a battery voltage error generated due to the memory effect of the secondary battery is calculated,
Calculating the correction value such that the difference between the voltage error measurement value and the voltage error estimation value is small;
A battery voltage estimation curve is calculated by applying the correction value to a fluctuation curve of an initial electromotive voltage of the secondary battery with respect to the charging rate, and a lower limit output voltage set in advance for the secondary battery; The difference between the battery voltage estimation curve and the discharge power allowable value indicating the allowable amount of power that can be discharged from the secondary battery is output,
A memory effect generating charging rate indicating the charging rate at which the memory effect is generated, and a rising fluctuation voltage indicating a voltage increasing amount of the secondary battery generated when the charging rate is higher than the memory effect generating charging rate. And a falling fluctuation voltage indicating a voltage drop amount of the secondary battery generated at a charging rate lower than the memory effect generating charging rate,
The voltage error model includes a charge rate change range as a fixed value, the charge rate change range indicating the range of the charge rate in which the voltage change amount is switched from positive to negative, with the memory effect occurrence charge rate being the center of the range. . It is executed by a calculation unit capable of executing a program, and a voltage measurement value indicating the temperature of the secondary battery, a voltage output from the secondary battery, and a current measurement value indicating the magnitude of the current output from the secondary battery. And obtaining a correction value by estimating a fluctuation amount of the output voltage of the secondary battery based on the temperature, the voltage measurement value, and the current measurement value, and from the secondary battery based on the correction value. A control program for a secondary battery that controls the output power,
A voltage obtained by estimating the voltage of the secondary battery based on a battery voltage model having as parameters the battery current value indicating the magnitude of the current discharged from the secondary battery and the temperature information indicating the temperature of the secondary battery. Calculate an estimate,
The difference between the voltage measurement value and the voltage estimation value is calculated as a voltage error measurement value,
Estimating the charging rate of the secondary battery based on the battery current value,
Using a voltage error model with the charging rate and the correction value as parameters, a voltage error estimation value indicating a battery voltage error generated due to the memory effect of the secondary battery is calculated,
Calculating the correction value such that the difference between the voltage error measurement value and the voltage error estimation value is small;
A battery voltage estimation curve is calculated by applying the correction value to a fluctuation curve of an initial electromotive voltage of the secondary battery with respect to the charging rate, and a lower limit output voltage set in advance for the secondary battery; The difference between the battery voltage estimation curve and the discharge power allowable value indicating the allowable amount of power that can be discharged from the secondary battery is output,
A memory effect generating charging rate indicating the charging rate at which the memory effect is generated, and a rising fluctuation voltage indicating a voltage increasing amount of the secondary battery generated when the charging rate is higher than the memory effect generating charging rate. And a falling fluctuation voltage indicating a voltage drop amount of the secondary battery generated at a charging rate lower than the memory effect generating charging rate,
The voltage error model is a control program for a secondary battery including, as a fixed value, a charge rate change range indicating a range of a charge rate in which the voltage change amount is switched from positive to negative, with the memory effect generation charge rate being the center of the range. .

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