JP5535968B2 - CHARGE RATE ESTIMATION DEVICE, CHARGE RATE ESTIMATION METHOD, AND PROGRAM - Google Patents

Description

  The present invention relates to a charging rate estimation device, a charging rate estimation method, and a program for estimating a charging rate of a secondary battery in operation.

  In general, the SOC (State Of Charge) of a secondary battery is calculated using the following formula (1).

However, S (t) indicates the SOC after time t, and S (0) indicates the SOC in the initial state. Further, I _t (t) represents a charge / discharge current at time t. Note that I _t (t) takes a positive value during charging and takes a negative value during discharging. Q indicates the full charge capacity of the secondary battery. That is, conventionally, the SOC of the secondary battery is calculated using the integrated value of the charge / discharge current of the secondary battery.

In addition, when calculating SOC discretely, Formula (1) 'which converted Formula (1) into the discrete function is used. However, S (n-1) is the SOC of the secondary battery at the time corresponding to the calculation cycle. T _s indicates a calculation cycle.

  However, when the SOC is calculated using the integrated value of the charge / discharge current of the secondary battery, the current detection error is accumulated due to the integration, and the calculated SOC after a predetermined time elapses is greatly different from the actual SOC. There is a risk that.

  As a method for solving this problem, Patent Document 1 discloses a method of estimating the open-circuit voltage of a secondary battery on the assumption that the charging / discharging of current is reversed and determining the SOC from the open-circuit voltage. Has been. When the secondary battery is not in a static state, the open circuit voltage cannot be accurately estimated due to the impedance inside the secondary battery. Therefore, the SOC in the initial state is corrected using the SOC obtained from the open circuit voltage in the static state. A method of obtaining the SOC using the current integrated value is used.

Japanese Patent Laid-Open No. 11-206028

  However, when using the method of correcting the SOC in the initial state when the secondary battery is in a static state, there is a problem that the error of the current integrated value is not eliminated until the secondary battery is in a static state. In addition, when calculating SOC using Formula (1) or Formula (1) ', the cause of the error is a change in the full charge capacity Q due to battery deterioration. For example, when the product life is up to 70% of the nominal battery capacity, the full charge capacity is reduced by 30% from the nominal battery capacity, which causes a large error in SOC estimation.

The present invention has been made in order to solve the above-described problem, and is a charging rate estimation device that estimates the charging rate of a secondary battery in operation, and the measured current of the secondary battery at a first time and Using the measured voltage, the charging rate of the secondary battery at the first time is calculated, and the measured current and the measured voltage of the secondary battery at a second time that is a time after the first time. And the charging rate calculation unit for calculating the charging rate of the secondary battery at the second time, and the charging rate calculation unit from the charging rate at the second time calculated by the charging rate calculation unit. A charge rate change amount calculation unit for calculating a charge rate change amount by subtracting the calculated charge rate at the first time, and charge / discharge of the secondary battery from the first time to the second time Current value integration that calculates the integrated value of the measured current by And dividing the integrated value of the current calculated by the current value integrating unit by the charging rate change calculated by the charging rate change calculating unit, thereby obtaining the full charge capacity of the secondary battery at the second time. A charging rate of the secondary battery is estimated using a full charge capacity calculation unit to be calculated, a full charge capacity calculated by the full charge capacity calculation unit, and an integrated value of an actually measured current due to charging and discharging of the secondary battery. A charging rate estimation unit , wherein the charging rate estimation unit uses the full charge capacity calculated by the full charge capacity calculation unit, the integrated value of the measured current due to charging / discharging of the secondary battery, and the error of the measured current. The upper limit value and the lower limit value of the charging rate of the secondary battery are calculated, and when the charging rate calculated by the charging rate calculation unit is equal to or higher than the upper limit value of the charging rate, the upper limit value of the charging rate is set to the second value. Estimated as the charge rate of the secondary battery, and the charge rate calculated by the charge rate calculator When the rate is equal to or lower than the lower limit value of the charging rate, the lower limit value of the charging rate is estimated as the charging rate of the secondary battery, and the charging rate calculated by the charging rate calculation unit is the upper limit value of the charging rate. The charging rate at the second time calculated by the charging rate calculation unit is estimated as the charging rate of the secondary battery. .

  In the present invention, it is preferable that the charging rate estimation unit further calculates a lower limit value and an upper limit value of the charging rate of the secondary battery using a measurement error of the full charge capacity of the secondary battery.

  The present invention is also a charging rate estimation device for estimating a charging rate of a secondary battery in operation, wherein the first current is measured using a measured current and a measured voltage of the secondary battery at a first time. The charging rate of the secondary battery at the time is calculated, and the measured current and the measured voltage of the secondary battery at the second time, which is a time after the first time, are used at the second time. A charging rate calculation unit that calculates a charging rate of the secondary battery, and a charging rate at the first time calculated by the charging rate calculation unit from a charging rate at the second time calculated by the charging rate calculation unit. A charging rate change amount calculation unit that calculates a charging rate change amount by subtracting, and a current value that calculates an integrated value of measured currents due to charging / discharging of the secondary battery from the first time to the second time The integration unit and the current calculated by the current value integration unit. A full charge capacity calculation unit for calculating a full charge capacity of the secondary battery at the second time by dividing the calculated value by the charge rate change calculated by the charge rate change calculation unit; and the full charge A charge rate estimation unit that estimates a charge rate of the secondary battery using a full charge capacity calculated by a capacity calculation unit and an integrated value of an actually measured current due to charging and discharging of the secondary battery; The time is a time when the measured temperature or the measured current of the secondary battery is within a predetermined range, and the second time is between the first time and the time. It is a time when the actually measured temperature or the actually measured current does not exceed a predetermined range.

The present invention is also a charging rate estimation device for estimating a charging rate of a secondary battery in operation, wherein the first current is measured using a measured current and a measured voltage of the secondary battery at a first time. The charging rate of the secondary battery at the time is calculated, and the measured current and the measured voltage of the secondary battery at the second time, which is a time after the first time, are used at the second time. A charging rate calculation unit that calculates a charging rate of the secondary battery, and a charging rate at the first time calculated by the charging rate calculation unit from a charging rate at the second time calculated by the charging rate calculation unit. A charging rate change amount calculation unit that calculates a charging rate change amount by subtracting, and a current value that calculates an integrated value of measured currents due to charging / discharging of the secondary battery from the first time to the second time The integration unit and the current calculated by the current value integration unit. A full charge capacity calculation unit for calculating a full charge capacity of the secondary battery at the second time by dividing the calculated value by the charge rate change calculated by the charge rate change calculation unit; and the full charge A function estimation unit that estimates a function indicating the relationship between time and full charge capacity from the full charge capacities of a plurality of secondary batteries calculated at different times by the capacity calculation unit, and a function estimated by the function estimation unit The charging rate for identifying the charging rate of the secondary battery using the full charging capacity and the integrated value of the measured current due to charging / discharging of the secondary battery, specifying the full charging capacity of the secondary battery at the current time An estimation unit, wherein the function estimation unit is a difference between the full charge capacity of the secondary battery calculated at the previous time among the full charge capacities of the secondary battery calculated at different times by the full charge capacity calculation unit. Or the difference from the full charge capacity indicated by the estimated function is Characterized by using one that does not exceed the value in the estimation of the function.

The present invention is also a charging rate estimation device for estimating a charging rate of a secondary battery in operation, wherein the first current is measured using a measured current and a measured voltage of the secondary battery at a first time. The charging rate of the secondary battery at the time is calculated, and the measured current and the measured voltage of the secondary battery at the second time, which is a time after the first time, are used at the second time. A charging rate calculation unit that calculates a charging rate of the secondary battery, and a charging rate at the first time calculated by the charging rate calculation unit from a charging rate at the second time calculated by the charging rate calculation unit. A charging rate change amount calculation unit that calculates a charging rate change amount by subtracting, and a current value that calculates an integrated value of measured currents due to charging / discharging of the secondary battery from the first time to the second time The integration unit and the current calculated by the current value integration unit. A full charge capacity calculation unit for calculating a full charge capacity of the secondary battery at the second time by dividing the calculated value by the charge rate change calculated by the charge rate change calculation unit; and the full charge A function estimation unit that periodically estimates a function indicating the relationship between time and full charge capacity from the full charge capacities of a plurality of secondary batteries calculated at different times by the capacity calculation unit, and a function estimated by the function estimation unit The full charge capacity of the secondary battery at the current time is identified with reference to the above, and the charge rate of the secondary battery is estimated using the full charge capacity and the integrated value of the measured current due to charge / discharge of the secondary battery A charging rate estimation unit that monitors the change of the coefficient of time in the function estimated by the function estimation unit, and a warning unit that issues a warning when the change of the coefficient is equal to or greater than a predetermined threshold. Features.

Further, in the present invention, the charging rate calculation unit calculates an open voltage of the secondary battery from the measured current and measured voltage of the secondary battery, and the relationship between the open voltage of the secondary battery and the charging rate is calculated. It is preferable to calculate the charging rate of the secondary battery from the calculated open circuit voltage with reference to the table shown.

  The present invention is also a charge rate estimation method for estimating a charge rate of a secondary battery in operation, wherein the first current is measured using a measured current and a measured voltage of the secondary battery at a first time. Using the step of calculating the charging rate of the secondary battery at the time, and the measured current and measured voltage of the secondary battery at a second time that is a time after the first time, Calculating a charging rate of the secondary battery at a time; calculating a charging rate change amount by subtracting the charging rate at the first time from the charging rate at the second time; and the first Calculating the integrated value of the measured current due to charging / discharging of the secondary battery from the time to the second time, and dividing the integrated value of the current by the amount of change in the charging rate, The secondary battery is full at the time An upper limit value and a lower limit of the charging rate of the secondary battery using the step of calculating the electric capacity, the calculated full charge capacity, the integrated value of the measured current due to charging and discharging of the secondary battery, and the error of the measured current A step of calculating a value, a step of estimating an upper limit value of the charging rate as a charging rate of the secondary battery when the calculated charging rate is equal to or greater than an upper limit value of the charging rate, and the calculated charging rate. Is lower than the lower limit value of the charging rate, the step of estimating the lower limit value of the charging rate as the charging rate of the secondary battery, and the calculated charging rate is less than the upper limit value of the charging rate and the charging And a step of estimating the calculated charge rate at the second time as the charge rate of the secondary battery when a value between the lower limit value of the rate is indicated.

The present invention is also a charge rate estimation method for estimating a charge rate of a secondary battery in operation, wherein the first current is measured using a measured current and a measured voltage of the secondary battery at a first time. Using the step of calculating the charging rate of the secondary battery at the time, and the measured current and measured voltage of the secondary battery at a second time that is a time after the first time, Calculating a charging rate of the secondary battery at a time; calculating a charging rate change amount by subtracting the charging rate at the first time from the charging rate at the second time; and the first Calculating the integrated value of the measured current due to charging / discharging of the secondary battery from the time to the second time, and dividing the integrated value of the current by the amount of change in the charging rate, The secondary battery is full at the time A step of calculating an electric capacity, and a step of estimating a charging rate of the secondary battery using a full charge capacity of the secondary battery and an integrated value of an actually measured current due to charging and discharging of the secondary battery. The first time is a time when the measured temperature or measured current of the secondary battery is within a predetermined range, and the second time is between the first time and the time. The time when the measured temperature or measured current of the secondary battery does not exceed a predetermined range.

The present invention is also a charge rate estimation method for estimating a charge rate of a secondary battery in operation, wherein the first current is measured using a measured current and a measured voltage of the secondary battery at a first time. Using the step of calculating the charging rate of the secondary battery at the time, and the measured current and measured voltage of the secondary battery at a second time that is a time after the first time, Calculating a charging rate of the secondary battery at a time; calculating a charging rate change amount by subtracting the charging rate at the first time from the charging rate at the second time; and the first Calculating the integrated value of the measured current due to charging / discharging of the secondary battery from the time to the second time, and dividing the integrated value of the current by the amount of change in the charging rate, The secondary battery is full at the time A step of calculating a capacity, a step of estimating a function indicating a relationship between time and a full charge capacity from the full charge capacities of a plurality of secondary batteries calculated at different times, and a current time with reference to the estimated function Identifying the full charge capacity of the secondary battery in the battery, and estimating the charge rate of the secondary battery using the full charge capacity and the integrated value of the measured current due to charge and discharge of the secondary battery. In the step of estimating the function, among the full charge capacities of the secondary batteries calculated at different times, the difference from the full charge capacity of the secondary battery calculated at the immediately preceding time or the full charge capacity indicated by the estimated function What is different is that the difference between the values does not exceed a predetermined threshold value is used for the estimation of the function.
  The present invention is also a charge rate estimation method for estimating a charge rate of a secondary battery in operation, wherein the first current is measured using a measured current and a measured voltage of the secondary battery at a first time. Using the step of calculating the charging rate of the secondary battery at the time, and the measured current and measured voltage of the secondary battery at a second time that is a time after the first time, Calculating a charging rate of the secondary battery at a time; calculating a charging rate change amount by subtracting the charging rate at the first time from the charging rate at the second time; and the first Calculating the integrated value of the measured current due to charging / discharging of the secondary battery from the time to the second time, and dividing the integrated value of the current by the amount of change in the charging rate, The secondary battery is full at the time A step of calculating an electric capacity, a step of periodically estimating a function indicating a relationship between time and a full charge capacity from the full charge capacities of a plurality of secondary batteries calculated at different times, and referring to the estimated function The step of specifying the full charge capacity of the secondary battery at the current time and estimating the charge rate of the secondary battery using the full charge capacity and the integrated value of the measured current due to charge / discharge of the secondary battery And monitoring a change in a coefficient of time in the estimated function, and issuing a warning when the change in the coefficient is equal to or greater than a predetermined threshold value.

According to the present invention, a computer of a charging rate estimation device that estimates a charging rate of a secondary battery in operation uses the measured current and measured voltage of the secondary battery at a first time, The charging rate of the secondary battery at the time is calculated, and the measured current and the measured voltage of the secondary battery at the second time, which is a time after the first time, are used at the second time. A charging rate calculation unit that calculates the charging rate of the secondary battery, and subtracts the charging rate at the first time calculated by the charging rate calculation unit from the charging rate at the second time calculated by the charging rate calculation unit. Thus, a charge rate change amount calculation unit for calculating the charge rate change amount, a current value integration unit for calculating an integrated value of the measured current due to charging / discharging of the secondary battery from the first time to the second time , The current calculated by the current value integrating unit A full charge capacity calculation unit for calculating a full charge capacity of the secondary battery at the second time by dividing the integrated value by the charge rate change calculated by the charge rate change calculation unit; Using the full charge capacity calculated by the calculation unit and the integrated value of the measured current due to charging / discharging of the secondary battery, the charge rate estimation unit that functions as a charge rate estimation unit that estimates the charge rate of the secondary battery, Is the upper limit value and lower limit of the charging rate of the secondary battery using the full charge capacity calculated by the full charge capacity calculation unit, the integrated value of the measured current due to charging and discharging of the secondary battery, and the error of the measured current When the charging rate calculated by the charging rate calculation unit is equal to or higher than the upper limit value of the charging rate, the upper limit value of the charging rate is estimated as the charging rate of the secondary battery, and the charging rate calculation is performed. The charging rate calculated by the unit is less than or equal to the lower limit value of the charging rate. The lower limit value of the charging rate is estimated as the charging rate of the secondary battery, and the charging rate calculated by the charging rate calculation unit is less than the upper limit value of the charging rate and the lower limit value of the charging rate. Is a program that estimates the charging rate at the second time calculated by the charging rate calculation unit as the charging rate of the secondary battery.

  According to the present invention, a computer of a charging rate estimation device that estimates a charging rate of a secondary battery in operation uses the measured current and measured voltage of the secondary battery at a first time, The charging rate of the secondary battery at the time is calculated, and the measured current and the measured voltage of the secondary battery at the second time, which is a time after the first time, are used at the second time. A charging rate calculation unit that calculates the charging rate of the secondary battery, and subtracts the charging rate at the first time calculated by the charging rate calculation unit from the charging rate at the second time calculated by the charging rate calculation unit. Thus, a charge rate change amount calculation unit for calculating the charge rate change amount, a current value integration unit for calculating an integrated value of the measured current due to charging / discharging of the secondary battery from the first time to the second time , The current calculated by the current value integrating unit A full charge capacity calculation unit for calculating a full charge capacity of the secondary battery at the second time by dividing the integrated value by the charge rate change calculated by the charge rate change calculation unit; Using the full charge capacity calculated by the calculation unit and the integrated value of the measured current due to charging / discharging of the secondary battery, it functions as a charging rate estimation unit that estimates the charging rate of the secondary battery, and the first time Is the time when the measured temperature or measured current of the secondary battery is within a predetermined range, and the second time is the time between the first time and the time of the secondary battery. The program is characterized in that the measured temperature or measured current is a time that does not exceed a predetermined range.

According to the present invention, a computer of a charging rate estimation device that estimates a charging rate of a secondary battery in operation uses the measured current and measured voltage of the secondary battery at a first time, The charging rate of the secondary battery at the time is calculated, and the measured current and the measured voltage of the secondary battery at the second time, which is a time after the first time, are used at the second time. A charging rate calculation unit that calculates the charging rate of the secondary battery, and subtracts the charging rate at the first time calculated by the charging rate calculation unit from the charging rate at the second time calculated by the charging rate calculation unit. Thus, a charge rate change amount calculation unit for calculating the charge rate change amount, a current value integration unit for calculating an integrated value of the measured current due to charging / discharging of the secondary battery from the first time to the second time , The current calculated by the current value integrating unit A full charge capacity calculation unit for calculating a full charge capacity of the secondary battery at the second time by dividing the integrated value by the charge rate change calculated by the charge rate change calculation unit; A function estimation unit that estimates a function indicating the relationship between time and full charge capacity from the full charge capacities of a plurality of secondary batteries calculated at different times by the calculation unit, and refers to the function estimated by the function estimation unit A charge rate estimation unit that specifies the full charge capacity of the secondary battery at the time and estimates the charge rate of the secondary battery using the full charge capacity and the integrated value of the measured current due to charge and discharge of the secondary battery The function estimation unit is configured to calculate or calculate a difference from a full charge capacity of the secondary battery calculated at the previous time among the full charge capacities of the secondary battery calculated at different times by the full charge capacity calculation unit. The difference from the full charge capacity indicated by the function Those that do not exceed a threshold which is a program, which comprises using the estimate of the function.
  According to the present invention, a computer of a charging rate estimation device that estimates a charging rate of a secondary battery in operation uses the measured current and measured voltage of the secondary battery at a first time, The charging rate of the secondary battery at the time is calculated, and the measured current and the measured voltage of the secondary battery at the second time, which is a time after the first time, are used at the second time. A charging rate calculation unit that calculates the charging rate of the secondary battery, and subtracts the charging rate at the first time calculated by the charging rate calculation unit from the charging rate at the second time calculated by the charging rate calculation unit. Thus, a charge rate change amount calculation unit for calculating the charge rate change amount, a current value integration unit for calculating an integrated value of the measured current due to charging / discharging of the secondary battery from the first time to the second time , The current calculated by the current value integrating unit A full charge capacity calculation unit for calculating a full charge capacity of the secondary battery at the second time by dividing the integrated value by the charge rate change calculated by the charge rate change calculation unit; A function estimation unit that periodically estimates a function indicating the relationship between time and full charge capacity from the full charge capacities of a plurality of secondary batteries calculated at different times by the calculation unit, see the function estimated by the function estimation unit Charging to estimate the charging rate of the secondary battery by specifying the full charging capacity of the secondary battery at the current time and using the full charging capacity and the integrated value of the measured current by charging and discharging of the secondary battery A rate estimator, a program for monitoring a change in a coefficient of time in a function estimated by the function estimator and functioning as a warning unit that issues a warning when the change in the coefficient is equal to or greater than a predetermined threshold .

  According to the present invention, the charging rate estimation device calculates a change amount of the charging rate from the first time to the second time, and calculates the full charge capacity of the secondary battery using the change amount. Thereby, the charging rate estimation apparatus can estimate the full charge capacity of the secondary battery regardless of whether or not the secondary battery is in a static state. The charging rate estimation device estimates the charging rate using the full charge capacity, the measured current, the voltage, and the temperature. Thereby, the charging rate estimation apparatus can estimate the charging rate in consideration of a change in full charge capacity due to deterioration of the secondary battery, regardless of whether or not the secondary battery is in a static state.

It is a schematic block diagram which shows the structure of the charging rate estimation apparatus by the 1st Embodiment of this invention. It is an example of the physical model which an open circuit voltage calculating part memorize | stores. It is a flowchart which shows the phase which specifies the full charge capacity by the charge rate estimation apparatus by 1st Embodiment. It is a figure which shows the example of the deterioration function estimated from the change rate of a full charge capacity. It is a flowchart which shows the phase which calculates SOC by the charging rate estimation apparatus by 1st Embodiment. It is a figure which shows the process outline | summary of a charging rate estimation apparatus. It is a schematic block diagram which shows the structure of the charging rate estimation apparatus by the 2nd Embodiment of this invention. It is a figure which shows an example of measured current value and an error. It is a schematic block diagram which shows the structure of the charging rate estimation apparatus by the 3rd Embodiment of this invention. It is a figure which shows the example of the full charge capacity to exclude. It is a figure which shows an example of the relationship between an open circuit voltage and SOCV. It is a schematic block diagram which shows the structure of the charging rate estimation apparatus by the 4th Embodiment of this invention. It is a figure which shows the example of SOC constant control logic. It is a schematic block diagram which shows the structure of the charging rate estimation apparatus by the 5th Embodiment of this invention.

<< First Embodiment >>
Hereinafter, a first embodiment of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a schematic block diagram showing a configuration of a charging rate estimation apparatus 100 according to the first embodiment of the present invention.
The charging rate estimation device 100 is a device that estimates the SOC (charging rate) of a secondary battery in operation, and includes a timing determination unit 101, an open-circuit voltage calculation unit 102, an SOCV calculation unit 103 (charging rate calculation unit), and an SOC change. Amount calculation unit 104 (charge rate change amount calculation unit), current value integration unit 105, full charge capacity calculation unit 106, function estimation unit 107, previous SOC storage unit 108, error storage unit 109, SOCI calculation unit 110, SOC estimation unit 111 (charge rate estimation unit) and display unit 112.

  Timing determination unit 101 outputs an SOC calculation instruction signal to open-circuit voltage calculation unit 102 and current value integration unit 105 at every predetermined cycle (hereinafter referred to as an SOC calculation cycle). Further, the timing determination unit 101 outputs a capacity calculation instruction signal to the SOC change amount calculation unit 104 every cycle that is an integral multiple of the SOC calculation cycle (hereinafter referred to as a capacity calculation cycle). In addition, the charging rate estimation apparatus 100 corrects the full charge capacity used for the SOC calculation based on the output of the capacity calculation instruction signal. The SOC calculation cycle is, for example, a cycle of about 0.1 to 1 second, and the capacity calculation cycle is, for example, a cycle of about 3600 seconds.

The open circuit voltage calculation unit 102 stores a physical model indicating the internal impedance of the secondary battery. FIG. 2 is an example of a physical model stored in the open circuit voltage calculation unit 102. Physical model shown in FIG. 2, the connecting the resistor R _a and a capacitor C _a in parallel circuit, the resistance R _d and the power supply is a circuit connected in series. When the open circuit voltage calculation unit 102 receives the SOC calculation instruction signal from the timing determination unit 101, the measured voltage, measured current, and measured temperature of the secondary battery, and the internal impedance value of the secondary battery obtained in advance. (R _a , C _a and R _d ) are used to calculate the open-circuit voltage V _ocv of the secondary battery.

The SOCV calculation unit 103 stores a table indicating the relationship between the open-circuit voltage of the secondary battery and the SOC, and the secondary battery is determined from the open-circuit voltage of the secondary battery calculated by the open-circuit voltage calculation unit 102 with reference to the table. Is calculated. Hereinafter, the SOC calculated by the SOCV calculation unit 103 is referred to as SOCV.
When the SOC change calculation unit 104 receives the SOC calculation instruction signal from the timing determination unit 101, the SOC change calculation unit 104 calculates the SOCV calculated when the SOCV calculation unit 103 received the previous SOC calculation instruction signal and the SOCV calculation unit 103 calculated this time. Is calculated as the SOC change amount of the secondary battery. That is, the SOC change amount calculation unit 104 calculates the difference between the SOCV at the time corresponding to the current capacity calculation cycle (second time) and the SOCV at the time corresponding to the previous capacity calculation cycle (first time). The calculation is made as the SOC change amount of the secondary battery.

When the SOC calculation instruction signal is received from the timing determination unit 101, the current value integration unit 105 acquires an actual measurement current value, and calculates an integrated current value per unit time by multiplying the actual measurement current value by the SOC calculation cycle. Then, the calculated current integrated value is added to the current integrated value calculated so far. Thereby, the current value integration unit 105 calculates the current integration value due to charging / discharging of the secondary battery up to the current time. The current value integration unit 105 resets the calculated current integration value to 0 when the full charge capacity calculation unit 106 calculates the full charge capacity of the secondary battery.
The full charge capacity calculation unit 106 divides the current integration value calculated by the current value integration unit 105 by the SOC change amount calculated by the SOC change amount calculation unit 104, so that the secondary battery at the time corresponding to the capacity calculation cycle is obtained. Calculate the full charge capacity. In addition, the full charge capacity calculation unit 106 updates the calculated full charge capacity using the function estimated by the function estimation unit 107.
The function estimation unit 107 estimates a function indicating the battery deterioration ratio using the full charge capacity calculated at different times by the full charge capacity calculation unit 106.
The previous SOC storage unit 108 stores the SOC of the secondary battery calculated at a time corresponding to the previous capacity calculation cycle. In addition, the pre-SOC storage unit 108 stores the SOC of the secondary battery measured in advance before starting the operation of the secondary battery.
The error storage unit 109 stores an error estimated for the actually measured current and an error estimated for the full charge capacity calculated by the full charge capacity calculation unit 106.

The SOCI calculation unit 110 includes the full charge capacity calculated by the full charge capacity calculation unit 106, the current integration value calculated by the current value integration unit 105, the SOC stored in the previous SOC storage unit 108, and the error stored in the error storage unit 109. Is used to calculate the SOC upper limit (hereinafter referred to as SOCI _max ) and the SOC lower limit (hereinafter referred to as SOCI _min ) estimated as the SOC of the secondary battery at the current time.
In addition, when the function is not estimated by the function estimation unit 107, such as when the operation of the secondary battery is shortly started, the SOCI calculation unit 110 does not specify the full charge capacity using the function, and the full charge capacity The SOCI is calculated using the full charge capacity calculated by the calculation unit 106.

The SOC estimation unit 111 estimates the SOC of the secondary battery by comparing the SOCI _max and SOCI _min calculated by the SOCI calculation unit 110 with the SOCV calculated by the SOCV calculation unit 103. The SOC estimation unit 111 records the estimated SOC in the previous SOC storage unit 108 and outputs it to the display unit 112.
Display unit 112 displays the SOC of the secondary battery estimated by SOC estimation unit 111.

Next, the operation of the charging rate estimation apparatus 100 according to the first embodiment will be described.
FIG. 3 is a flowchart showing a phase for specifying the full charge capacity by the charging rate estimation apparatus 100 according to the first embodiment.
When the charging rate estimation apparatus 100 starts estimating the SOC of the secondary battery, the timing determination unit 101 outputs an SOC calculation instruction signal at the SOC calculation period and outputs a capacity calculation instruction signal at the capacity calculation period. Since the capacity calculation cycle is an integer multiple of the SOC calculation cycle, the capacity calculation instruction signal is always output at the same time as the SOC calculation instruction signal.

  First, open-circuit voltage calculation unit 102 and current value integration unit 105 determine whether or not timing determination unit 101 has output an SOC calculation instruction signal (step S101). When the timing determination unit 101 does not output the SOC calculation instruction signal (step S101: NO), the open circuit voltage calculation unit 102 and the current value integration unit 105 wait for the timing determination unit 101 to output the SOC calculation instruction signal.

  On the other hand, when the timing determination unit 101 outputs the SOC calculation instruction signal (step S101: YES), the open circuit voltage calculation unit 102 acquires the measured voltage and measured current of the secondary battery at the current time, and performs the physical processing shown in FIG. By applying to the model, the open-circuit voltage of the secondary battery is calculated (step S102). Next, the SOCV calculation unit 103 calculates an SOCV from the open circuit voltage calculated by the open circuit voltage calculation unit 102 with reference to a table indicating the relationship between the open circuit voltage and the SOC (step S103).

  On the other hand, when the current value integrating unit 105 receives the SOC calculation instruction signal from the timing determining unit 101, the current value integrating unit 105 acquires the measured current of the secondary battery at the current time, multiplies the measured current by the SOC calculation cycle, and calculates the calculated value. The current integrated value up to the current time is calculated by adding to the current integrated value calculated up to (step S104). Specifically, the current integrated value Ah in the SOC calculation cycle is calculated using the following equation (2).

However, the denominator 3600 is a constant for setting the unit of the current integrated value to Ah (ampere time). In addition, I _m (n) is an actually measured current of the secondary battery at time n, and T _s is an SOC calculation cycle.
If the current consumption I _Loss (n) by the control circuit power supply or cell voltage balance circuit connected in parallel to the secondary battery is known in advance, the current integration is performed using equation (3) instead of equation (2). It is preferable to calculate the value Ah.

  Next, the SOC change amount calculation unit 104 determines whether or not the timing determination unit 101 has output a capacity calculation instruction signal (step S105). When the timing determination unit 101 outputs a capacity calculation instruction signal (step S105: YES), the SOC change amount calculation unit 104 receives the SOCV calculated by the SOCV calculation unit 103 and the SOCV calculation unit 103 receives the previous capacity calculation instruction signal. The SOC change amount is calculated by obtaining the difference from the calculated SOCV (step S106). Note that the SOCV calculated when the SOCV calculation unit 103 received the previous capacity calculation instruction signal is stored in the internal memory of the SOC change amount calculation unit 104. In addition, at the time of the first execution, since there is no SOCV calculated by the previous SOCV calculation unit 103, the SOC change amount is calculated using the SOC of the secondary battery that has been measured in advance instead.

  Next, the full charge capacity calculation unit 106 divides the current integration value calculated by the current value integration unit 105 by the SOC change amount calculated by the SOC change amount calculation unit 104, thereby fully charging the secondary battery at the current time. The capacity is calculated (step S107). At this time, the current value integrating unit 105 resets the integrated current value up to the current time to 0 (step S108).

  Next, the function estimation unit 107 calculates the change rate of the full charge capacity by dividing the full charge capacity calculated by the full charge capacity calculation unit 106 by the initial full charge capacity (nominal battery capacity) of the secondary battery. Then, the change rate of the full charge capacity is recorded in the internal memory in association with the current time (step S109). Next, the function estimation unit 107 determines whether or not the number of change rates of the full charge capacity stored in the internal memory has become a predetermined number or more (step S110).

  When the function estimation unit 107 determines that the stored change rate of the full charge capacity is equal to or greater than the predetermined number (step S110: YES), the function estimation unit 107 uses the change rate of the full charge capacity to fill the secondary battery. A deterioration function indicating the relationship between the charge capacity and time (or elapsed time from the start of use) is estimated (step S111).

FIG. 4 is a diagram illustrating an example of a deterioration function estimated from the rate of change of the full charge capacity.
Specifically, by performing a regression analysis process on the combination of the rate of change of the full charge capacity stored in the internal memory and the time, an approximation indicating the deterioration of the secondary battery over time as shown in FIG. A curve is estimated, and the function of the approximate curve is used as a deterioration function. In addition, when the tendency of deterioration is known in advance by the operation of another secondary battery, it is preferable to previously specify the type of approximate curve (for example, a linear function, a high-order function, a logarithmic function, etc.).

  When the function estimation unit 107 estimates the deterioration function, the full charge capacity calculation unit 106 specifies the battery deterioration ratio of the secondary battery at the current time from the deterioration function, as shown in FIG. Is multiplied by the battery deterioration ratio to calculate the full charge capacity (step S112). Then, the full charge capacity calculation unit 106 updates the full charge capacity calculated in step S107 to the full charge capacity calculated in step S112.

  Here, the reason for calculating the full charge capacity using the deterioration function will be described. The full charge capacity calculation unit 106 uses the SOCV for calculation of the full charge capacity. In addition, the open circuit voltage calculated by the open circuit voltage calculation unit 102 is used for the calculation of the SOCV. The open-circuit voltage calculation unit 102 calculates the open-circuit voltage using a physical model. However, since the physical model does not necessarily match an actual secondary battery, the calculation result includes a model error. For this reason, the full charge capacity calculated by the full charge capacity calculation unit 106 is not limited and variations due to model errors occur. Therefore, by estimating the deterioration function by estimating the approximate curve in step S110 and calculating the full charge capacity using the deterioration function, variation due to model error can be reduced.

FIG. 5 is a flowchart showing a phase for calculating the SOC by the charging rate estimation apparatus 100 according to the first embodiment.
If it is determined in step S103 that the capacity calculation instruction signal is not output (step S103: NO), the function estimation unit 107 stores the number of change rates of the full charge capacity that is less than the predetermined number in step S110. (Step S110: NO), or when the full charge capacity calculation unit 106 updates the full charge capacity in step S113, the SOCI calculation unit 110 calculates the full charge capacity last calculated by the full charge capacity calculation unit 106. The current integrated value calculated by the current value integrating unit 105, the SOC stored in the previous SOC storage unit 108, and the error stored in the error storage unit 109 are applied to the following equations (4) and (5). Thus, SOCI _max and SOCI _min are calculated (step S114).

Here, S _max (n) represents the SOCI _max of the secondary battery at time n, and S _min (n) represents the SOCI _min of the secondary battery at time n. S (n-1) is the SOC of the secondary battery at the time corresponding to the previous SOC calculation cycle. Q _e is a full charge capacity obtained by calculation. I _m (n) is a current value at time n.
The coefficient A is a constant shown in the equation (6).

A denominator 3600 is a constant for setting the unit of the current integrated value to Ah (ampere time). Further, 100, which is the numerator of A, is a constant for displaying the SOC as a percentage. Further, T _s is an SOC calculation cycle, and represents a current integrated value by multiplying by I _m (n) included in the expressions (4) and (5).
Further, ΔS _err (n) included in Expression (4) and Expression (5) is an SOC error at time n, and is expressed by Expression (7).

ΔQ _e indicates a full charge capacity error, and ΔI _m (n) indicates an actually measured current error. As shown in Equation (7), four values are calculated as the SOC error depending on whether the upper limit value or lower limit value of the full charge capacity error is used or the upper limit value or lower limit value of the measured current error is used. can do. Among these, max (ΔS _err (n)) included in the equation (4) represents the maximum value of the SOC error, and min (ΔS _err (n)) included in the equation (5) represents the minimum value of the SOC error. Indicates.

In the above formulas (4) and (5), I _m (n) ± ΔI _m (n) is substituted for I (n) of formula (1) ′, and Q _e ± ΔQ _e is substituted for Q. This is an expansion of this.

In the calculation of the SOC in step S109, the SOC stored in the previous SOC storage unit 108 is S (n-1), the current integration value calculated by the current value integration unit 105 is I _m (n) T _s, and The full charge capacity calculated last by the charge capacity calculation unit 106 is defined as Q _e . Further, the error of the full charge capacity stored in the error storage unit 109 is represented by ΔQ _e , and the error of the actually measured current stored in the error storage unit 109 is represented by ΔI _m (n).

When the SOCI calculation unit 110 calculates SOCI _max and SOCI _min in step S114, the SOC estimation unit 111 calculates the SOCV calculated by the SOCV calculation unit 103 in step S103, and the SOCI _max and SOCI _min calculated by the SOCI calculation unit 110. Compare (step S115). When SOC estimation unit 111 determines that SOCV is equal to or greater than SOCI _max (step S115: SOCV ≧ SOCI _max ), it estimates SOCI _max as the SOC of the secondary battery (step S116). In addition, when SOC estimation unit 111 determines that SOCV is equal to or lower than SOCI _min (step S115: SOCI _min ≧ SOCV), it estimates SOCI _min as the SOC of the secondary battery (step S117). When SOC estimation unit 111 determines that SOCV is larger than SOCI _min and smaller than SOCI _max (step S115: SOCI _max >SOCV> SOCI _min ), SOCV is estimated as the SOC of the secondary battery (step S118). ).

  When SOC estimation of the secondary battery is estimated in any of steps S116 to S118, SOC estimation unit 111 records the SOC in previous SOC storage unit 108 (step S119). Moreover, the SOC estimation part 111 outputs the estimated SOC to the display part 112 (step S120). Thereby, display unit 112 can display the SOC of the secondary battery at the current time.

FIG. 6 is a diagram showing a processing outline of the charging rate estimation apparatus 100.
When the timing determination unit 101 outputs a capacity calculation instruction signal at time n shown in FIG. 6, the full charge capacity calculation unit 106 calculates the full charge capacity. As shown in FIG. 6, at time n, SOCV calculation unit 103 calculates SOCV, and SOCI calculation unit 110 calculates SOCI _max and SOCI _min . At time n, since SOCV is equal to or higher than SOCI _max , charging rate estimation apparatus 100 estimates SOCI _max as the SOC of the secondary battery at time n.
In addition, from time n to time n + 1, the SOCV calculation unit 103 calculates SOCV for each SOC calculation cycle, the SOCI calculation unit 110 calculates SOCI _max and SOCI _min , and the charging rate estimation apparatus 100 performs the SOCV Based on the SOCI _max and the SOCI _min , the SOC of the secondary battery at that time is estimated.

When the timing determination unit 101 outputs a capacity calculation instruction signal at time n + 1, the full charge capacity calculation unit 106 calculates the full charge capacity. The SOCV calculation unit 103 calculates SOCV, and the SOCI calculation unit 110 calculates SOCI _max and SOCI _min . At time n + 1, since SOCV is equal to or lower than SOCI _min , charging rate estimation apparatus 100 estimates SOCI _min as the SOC of the secondary battery at time n + 1.
In addition, from time n + 1 to time n + 2, the SOCV calculation unit 103 calculates SOCV at every SOC calculation cycle, the SOCI calculation unit 110 calculates SOCI _max and SOCI _min , and the charging rate estimation apparatus 100 performs the SOCV Based on the SOCI _max and the SOCI _min , the SOC of the secondary battery at that time is estimated.

When the timing determination unit 101 outputs a capacity calculation instruction signal at time n + 2, the full charge capacity calculation unit 106 calculates the full charge capacity. The SOCV calculation unit 103 calculates SOCV, and the SOCI calculation unit 110 calculates SOCI _max and SOCI _min . At time n + 2, since SOCV is a value between SOCI _max and SOCI _min , charging rate estimation apparatus 100 estimates SOCV as the SOC of the secondary battery at time n + 2.

  As described above, according to the present embodiment, the charging rate estimation apparatus 100 calculates the SOC change amount during the capacity calculation cycle, and calculates the full charge capacity of the secondary battery using the change amount. Thereby, the full charge capacity of the secondary battery can be estimated regardless of whether or not the secondary battery is in a static state. Then, the charging rate estimation apparatus 100 calculates the SOCI using the full charge capacity and the current integrated value. Thereby, regardless of whether or not the secondary battery is in a static state, it is possible to estimate the SOC in consideration of the change in the full charge capacity due to the deterioration of the secondary battery.

Further, according to the present embodiment, when the SOCV value is within a reliable range (SOC _min to SOC _max reflecting the error of the measured current), the SOCV value is set to the SOC at the current time. Estimated. On the other hand, if the SOCV value is not within a reliable range, the SOC _min or SOC _max that is close to the SOCV is estimated as the SOC at the current time.
Therefore, even when the estimated open-circuit voltage value of the secondary battery is unreliable, the current SOC is determined as a value that can be estimated to be optimal from the relationship between SOCV, SOCI _min, and SOCI _max . Thereby, it is possible to prevent past cumulative errors from being mixed in the calculated SOC value, and to improve the estimation accuracy of the SOC.

  In the present embodiment, the case where the current value integration unit 105 obtains the integrated value of the current discretely by multiplying the current value by the SOC calculation cycle has been described, but the present invention is not limited to this, and it may be obtained continuously. good.

<< Second Embodiment >>
Next, a second embodiment of the present invention will be described.
The current integration value calculated by the current value integration unit 105 in the charging rate estimation apparatus 100 according to the first embodiment may include a current detection error. Current detection errors include errors due to gain, hysteresis, offset, etc. Among these, errors due to offset have a particularly large effect on the current integrated value. The charging rate estimation apparatus 100 according to the second embodiment improves the SOC estimation accuracy by reducing the offset error of the current integrated value.

FIG. 7 is a schematic block diagram showing the configuration of the charging rate estimation apparatus 200 according to the second embodiment of the present invention.
The charging rate estimation apparatus 200 according to the second embodiment differs from the charging rate estimation apparatus 100 according to the first embodiment in operations of the timing determination unit 201, the SOC change amount calculation unit 204, and the current value integration unit 205.
Timing determination unit 201 outputs an SOC calculation instruction signal to open-circuit voltage calculation unit 102 and current value integration unit 205 at every SOC calculation cycle. In addition, the timing determination unit 201 specifies, for each SOC calculation cycle, a timing for performing SOC calculation preparation (first time) and a timing for performing SOC calculation (second time) from the measured temperature and the measured current. Then, the preparation instruction signal is output to the SOC change amount calculation unit 204 at the timing when the SOC calculation preparation is performed, and the capacity calculation instruction signal is output to the SOC change amount calculation unit 204 at the timing when the SOC calculation is performed.
The SOC change amount calculation unit 204 receives the SOC calculation instruction signal from the timing determination unit 101, and the SOCV calculated by the SOCV calculation unit 103 when the preparation instruction signal is received (first time), and the SOCV calculation unit 103. However, the difference from the SOCV calculated this time (second time) is calculated as the SOC change amount of the secondary battery.
Current value integrating section 205 integrates the measured current from when the preparation instruction signal is received to when the capacity calculation instruction signal is received every SOC calculation cycle.

Here, the timing specifying method by the timing determination unit 201 will be described in detail.
FIG. 8 is a diagram illustrating an example of measured current values and errors.
In the example shown in FIG. 8, the error characteristic of the current sensor depends on the temperature and the current value. Therefore, it is preferable to integrate the current values within a range where the current sensor error is small. In the example shown in FIG. 7, for example, when the measured current is from 15 A to 25 A and the measured temperature is from 20 ° C. to 30 ° C., the current values are preferably integrated.

Therefore, the timing determination unit 201 outputs a preparation instruction signal at a time when at least the moving average values of the measured temperature and the measured current are within a predetermined range, and from the time when the preparation instruction signal is output to the time. It is necessary to output a capacity calculation instruction signal at a time such that the measured temperature and the measured current do not exceed a predetermined range. Therefore, in this embodiment, the timing determination unit 201 outputs a preparation instruction signal when the measured current and the measured temperature transition from outside the range to the range, and the measured current and measured temperature transition from the range to the outside of the range. When this occurs, a capacity calculation instruction signal is output.
Therefore, according to the present embodiment, the charging rate estimation apparatus 200 corrects the SOC stored in the previous SOC storage unit 108 at the time when the previous actually measured current and the actually measured temperature transitioned from within the range to outside the range.

Thus, according to the present embodiment, the current value integration unit 205 determines that the measured current and the measured temperature have transitioned from the range to the outside of the range from the time when the measured current and the measured temperature have transitioned from the outside of the range to the range. Accumulate current values up to the time. Thereby, since the offset error of the current integrated value is reduced, the SOC estimation accuracy can be improved.

  In the present embodiment, the case where the output timing of the preparation instruction signal and the capacity calculation instruction signal is determined based on the measured current and the measured temperature is described, but the present invention is not limited to this. For example, the timing may be determined based only on the actually measured temperature, or the timing may be determined based only on the actually measured current.

<< Third Embodiment >>
Next, a third embodiment of the present invention will be described.
As described in the first embodiment, the full charge capacity calculated by the full charge capacity calculation unit 106 may include an error. In the first embodiment, the method for reducing the error by estimating the degradation function by the function estimation unit 107 has been described. In the third embodiment, a method for further reducing the error included in the degradation function. explain.

FIG. 9 is a schematic block diagram showing a configuration of a charging rate estimation apparatus 300 according to the third embodiment of the present invention.
The charging rate estimation apparatus 300 according to the third embodiment is different from the charging rate estimation apparatus 100 according to the first embodiment in the operation of the function estimation unit 307.
The function estimation unit 307 according to the third embodiment estimates a deterioration function by excluding the full charge capacity calculated by the full charge capacity calculation unit 106 and having a large error.

As a method of estimating the deterioration function by excluding abnormal data, for example, when the difference from the previously calculated full charge capacity is equal to or greater than a predetermined threshold, the previous full charge capacity is used instead of the current full charge capacity. A method of estimating a deterioration function using the charge capacity is mentioned.
As another method, the deterioration function is estimated from the change rate of the full charge capacity recorded by the function estimation unit 107 in a certain time interval, and the difference from the change rate of the full charge capacity derived from the deterioration function is a predetermined value. There is a method of excluding a change rate that is equal to or greater than a threshold and estimating a deterioration function again. FIG. 10 is a diagram illustrating an example of the full charge capacity to be excluded. In this case, the accuracy of the deterioration function can be improved by repeatedly executing the re-estimation process of the deterioration function.
Thus, according to the present embodiment, the function estimation unit 307 can increase the accuracy of the deterioration function by estimating the deterioration function by excluding the full charge capacity having a large error.

<< Fourth Embodiment >>
Next, a fourth embodiment of the present invention will be described.
FIG. 11 is a diagram illustrating an example of the relationship between the open circuit voltage and the SOCV.
The relationship between the open-circuit voltage of the secondary battery and the SOCV used for the SOCV calculation by the SOCV calculation unit 103 is not necessarily linear as shown in FIG. In the fourth embodiment, a method for improving the estimation accuracy of the full charge capacity in view of this point will be described.

FIG. 12 is a schematic block diagram showing the configuration of the charging rate estimation apparatus 400 according to the fourth embodiment of the present invention.
The charging rate estimation apparatus 400 according to the fourth embodiment differs from the charging rate estimation apparatus 100 according to the first embodiment in the operation of the full charge capacity calculation unit 406.
The full charge capacity calculation unit 406 according to the fourth embodiment monitors the SOC output from the SOC estimation unit 111. The full charge capacity calculation unit 406 calculates the full charge capacity when the SOC is within a range having linearity in relation to the open-circuit voltage of the secondary battery during the capacity calculation cycle, and the SOC is linear. The full charge capacity is not calculated when it is out of the range having the characteristics. In the example shown in FIG. 10, the full charge capacity is calculated only when the SOC is between 50% and 60%. Thereby, an error due to nonlinearity of the relationship between the SOCV and the open circuit voltage can be eliminated, and the estimation accuracy of the full charge capacity can be improved.

  By the way, when a secondary battery is normally used in the discharging direction, such as an electric vehicle, and the secondary battery is charged with nighttime power or the like, the SOC passes through a linear range during charging. Can be used to periodically estimate the full charge capacity. On the other hand, when a secondary battery is used when smoothing natural energy, the SOC does not necessarily pass through a linear range. Therefore, in this case, by using a predetermined SOC constant control logic, the smoothing target value, which is normally a constant value (for example, 50%), is changed at the time of battery capacity estimation (for example, to 60%), thereby linearity to the SOC. A range having

FIG. 13 is a diagram illustrating an example of the SOC constant control logic.
As shown in FIG. 13A, the device that charges and discharges the secondary battery determines the final charge and discharge command based on the instructions of the charge and discharge command and the SOC constant control logic. At this time, the SOC constant control logic normally outputs only the SOC target value (50%), but periodically adds a predetermined SOC (10%) to the SOC target value. As a result, the SOC target output from the SOC constant control logic changes between 50% and 60% as shown in FIG.

<< Fifth Embodiment >>
Next, a fifth embodiment of the present invention will be described.
The deterioration of the secondary battery is approximated by a deterioration function estimated by the function estimation unit 107. However, when some trouble occurs in the secondary battery, the deterioration mode may change. In the fifth embodiment, a method for displaying a warning when the deterioration mode of the secondary battery changes will be described.

FIG. 14 is a schematic block diagram showing a configuration of a charging rate estimation apparatus 500 according to the fifth embodiment of the present invention.
The charging rate estimation apparatus 500 according to the fifth embodiment is different from the charging rate estimation apparatus 100 according to the first embodiment in the operations of the function estimation unit 507 and the display unit 512 (warning unit).
The function estimation unit 507 according to the fifth embodiment estimates a deterioration function in a certain period. At this time, the function estimation unit 507 estimates a deterioration function using a linear function and monitors a change in a time coefficient. Then, the function estimation unit 507 estimates that the deterioration mode of the secondary battery has changed due to some factor when the change in the coefficient is equal to or greater than a predetermined threshold, and outputs warning information to the display unit 512.
The display unit 512 displays the warning information received from the function estimation unit 507.
Thereby, the charging rate estimation apparatus 500 can display a warning when it is assumed that the deterioration mode of the secondary battery has changed and some trouble has occurred.

As described above, the embodiment of the present invention has been described in detail with reference to the drawings. However, the specific configuration is not limited to the above, and various design changes and the like can be made without departing from the scope of the present invention. It is possible to
For example, in the first to fifth embodiments described above, the charging rate estimation device has been described as an external device provided separately from the secondary battery, but is not limited thereto. Specifically, a charge rate estimation device may be mounted on a BMU (Battery Management Unit) that is provided in the secondary battery and controls and monitors the secondary battery.

  Further, in the first to fifth embodiments, the case where the charging rate estimation device is mounted on one device has been described. However, the present invention is not limited to this, and for example, the timing determination unit 101 and the open-circuit voltage calculation unit 102. , SOCV calculation unit 103, SOC change amount calculation unit 104, current value integration unit 105, full charge capacity calculation unit 106, function estimation unit 107 are mounted on an external device, and pre-SOC storage unit 108, error storage unit 109, SOCI calculation The unit 110 and the SOC estimation unit 111 may be mounted on the BMU. At this time, whether the full charge capacity calculated by the full charge capacity calculation unit 106 of the external device or the full charge capacity derived from the deterioration function estimated by the function estimation unit 107 is determined automatically or manually. In the above, the full charge capacity may be output to the BMU.

  The above-described charging rate estimation apparatus has a computer system inside. The operation of each processing unit described above is stored in a computer-readable recording medium in the form of a program, and the above processing is performed by the computer reading and executing this program. Here, the computer-readable recording medium means a magnetic disk, a magneto-optical disk, a CD-ROM, a DVD-ROM, a semiconductor memory, or the like. Alternatively, the computer program may be distributed to the computer via a communication line, and the computer that has received the distribution may execute the program.

  The program may be for realizing a part of the functions described above. Furthermore, what can implement | achieve the function mentioned above in combination with the program already recorded on the computer system, and what is called a difference file (difference program) may be sufficient.

  DESCRIPTION OF SYMBOLS 100 ... Charging rate estimation apparatus 101, 201 ... Timing determination part 102 ... Open circuit voltage calculating part 103 ... SOCV calculating part 104, 204 ... SOC change amount calculating part 105, 205 ... Current value integrating | accumulating part 106,406 ... Full charge capacity calculating part 107, 307, 507 ... function estimation unit 108 ... previous SOC storage unit 109 ... error storage unit 110 ... SOCI calculation unit 111 ... SOC estimation unit 112, 512 ... display unit

Claims (14)

A charging rate estimation device for estimating a charging rate of a secondary battery in operation,
Using the measured current and measured voltage of the secondary battery at the first time, the charging rate of the secondary battery at the first time is calculated, and a second time that is later than the first time. A charge rate calculator that calculates the charge rate of the secondary battery at the second time using the measured current and measured voltage of the secondary battery at the time of
Charge rate change amount calculation for calculating the charge rate change amount by subtracting the charge rate at the first time calculated by the charge rate calculation unit from the charge rate at the second time calculated by the charge rate calculation unit. And
A current value integrating unit that calculates an integrated value of measured currents due to charging / discharging of the secondary battery from the first time to the second time;
The full charge capacity of the secondary battery at the second time is calculated by dividing the integrated value of the current calculated by the current value integrating unit by the charging rate change calculated by the charging rate change calculating unit. A full charge capacity calculator,
A charge rate estimating unit that estimates the charge rate of the secondary battery using the full charge capacity calculated by the full charge capacity calculating unit and the integrated value of the measured current due to charging and discharging of the secondary battery;
The charging rate estimation unit
Using the full charge capacity calculated by the full charge capacity calculation unit, the integrated value of the measured current due to charging / discharging of the secondary battery, and the error of the measured current, the upper limit value and the lower limit value of the charging rate of the secondary battery are calculated. Operate,
When the charging rate calculated by the charging rate calculation unit is equal to or higher than the upper limit value of the charging rate, the upper limit value of the charging rate is estimated as the charging rate of the secondary battery,
When the charging rate calculated by the charging rate calculation unit is equal to or lower than the lower limit value of the charging rate, the lower limit value of the charging rate is estimated as the charging rate of the secondary battery,
When the charge rate calculated by the charge rate calculation unit indicates a value between the charge rate less than the upper limit value and the lower limit value of the charge rate, the charge at the second time calculated by the charge rate calculation unit A charging rate estimation apparatus , wherein a rate is estimated as a charging rate of the secondary battery . The charging rate estimating part further using the measurement error of the full charge capacity of the secondary battery, according to claim 1, characterized in that calculating the lower limit and the upper limit of the charging rate of the secondary battery Charge rate estimation device. A charging rate estimation device for estimating a charging rate of a secondary battery in operation,
  Using the measured current and measured voltage of the secondary battery at the first time, the charging rate of the secondary battery at the first time is calculated, and a second time that is later than the first time. A charge rate calculator that calculates the charge rate of the secondary battery at the second time using the measured current and measured voltage of the secondary battery at the time of
  Charge rate change amount calculation for calculating the charge rate change amount by subtracting the charge rate at the first time calculated by the charge rate calculation unit from the charge rate at the second time calculated by the charge rate calculation unit. And
  A current value integrating unit that calculates an integrated value of measured currents due to charging / discharging of the secondary battery from the first time to the second time;
  The full charge capacity of the secondary battery at the second time is calculated by dividing the integrated value of the current calculated by the current value integrating unit by the charging rate change calculated by the charging rate change calculating unit. A full charge capacity calculator,
  A charge rate estimating unit for estimating a charge rate of the secondary battery using a full charge capacity calculated by the full charge capacity calculating unit and an integrated value of an actually measured current due to charging and discharging of the secondary battery;
  With
  The first time is a time when the measured temperature or measured current of the secondary battery is within a predetermined range;
  The second time is a time during which the measured temperature or measured current of the secondary battery does not exceed a predetermined range between the first time and the time.
  The charge rate estimation apparatus characterized by the above-mentioned. A charging rate estimation device for estimating a charging rate of a secondary battery in operation,
  Using the measured current and measured voltage of the secondary battery at the first time, the charging rate of the secondary battery at the first time is calculated, and a second time that is later than the first time. A charge rate calculator that calculates the charge rate of the secondary battery at the second time using the measured current and measured voltage of the secondary battery at the time of
  Charge rate change amount calculation for calculating the charge rate change amount by subtracting the charge rate at the first time calculated by the charge rate calculation unit from the charge rate at the second time calculated by the charge rate calculation unit. And
  A current value integrating unit that calculates an integrated value of measured currents due to charging / discharging of the secondary battery from the first time to the second time;
  The full charge capacity of the secondary battery at the second time is calculated by dividing the integrated value of the current calculated by the current value integrating unit by the charging rate change calculated by the charging rate change calculating unit. A full charge capacity calculator,
  A function estimation unit that estimates a function indicating a relationship between time and full charge capacity from the full charge capacity of a plurality of secondary batteries calculated at different times by the full charge capacity calculation unit;
  Identify the full charge capacity of the secondary battery at the current time with reference to the function estimated by the function estimation unit, using the full charge capacity and the integrated value of the measured current by charging and discharging the secondary battery, A charge rate estimator for estimating the charge rate of the secondary battery;
  With
  The function estimation unit indicates a difference between the full charge capacity of the secondary battery calculated at the previous time among the full charge capacities of the secondary battery calculated at different times by the full charge capacity calculation unit or an estimated function. A function whose difference from the full charge capacity does not exceed a predetermined threshold is used for the estimation of the function.
  The charge rate estimation apparatus characterized by the above-mentioned. A charging rate estimation device for estimating a charging rate of a secondary battery in operation,
  Using the measured current and measured voltage of the secondary battery at the first time, the charging rate of the secondary battery at the first time is calculated, and a second time that is later than the first time. A charge rate calculator that calculates the charge rate of the secondary battery at the second time using the measured current and measured voltage of the secondary battery at the time of
  Charge rate change amount calculation for calculating the charge rate change amount by subtracting the charge rate at the first time calculated by the charge rate calculation unit from the charge rate at the second time calculated by the charge rate calculation unit. And
  A current value integrating unit that calculates an integrated value of measured currents due to charging / discharging of the secondary battery from the first time to the second time;
  The full charge capacity of the secondary battery at the second time is calculated by dividing the integrated value of the current calculated by the current value integrating unit by the charging rate change calculated by the charging rate change calculating unit. A full charge capacity calculator,
  A function estimation unit that periodically estimates a function indicating the relationship between time and full charge capacity from the full charge capacity of a plurality of secondary batteries calculated at different times by the full charge capacity calculation unit;
  Identify the full charge capacity of the secondary battery at the current time with reference to the function estimated by the function estimation unit, using the full charge capacity and the integrated value of the measured current by charging and discharging the secondary battery, A charge rate estimator for estimating the charge rate of the secondary battery;
  A warning unit for monitoring a change in a coefficient of time in the function estimated by the function estimation unit and issuing a warning when the change in the coefficient is equal to or greater than a predetermined threshold;
  A charging rate estimation device comprising: The charging rate calculator is
The open circuit voltage of the secondary battery is calculated from the measured current and the measured voltage of the secondary battery, and the table showing the relationship between the open voltage of the secondary battery and the charging rate is used to calculate the open circuit voltage from the calculated open circuit voltage. The charge rate estimation apparatus according to any one of claims 1 to 5 , wherein a charge rate of a secondary battery is calculated. A charging rate estimation method for estimating a charging rate of a secondary battery in operation,
Using the measured current and measured voltage of the secondary battery at a first time to calculate the charging rate of the secondary battery at the first time;
Calculating the charge rate of the secondary battery at the second time using the measured current and the measured voltage of the secondary battery at a second time that is a time after the first time;
Calculating a charge rate change amount by subtracting the charge rate at the first time from the charge rate at the second time;
Calculating an integrated value of actually measured currents due to charging / discharging of the secondary battery from the first time to the second time;
A step of calculating a full charge capacity of the secondary battery at the second time by dividing the integrated value of the current by the charge rate change amount;
Calculating an upper limit value and a lower limit value of the charging rate of the secondary battery using the calculated full charge capacity, an integrated value of the measured current due to charging / discharging of the secondary battery, and an error of the measured current;
When the calculated charging rate is equal to or higher than the upper limit value of the charging rate, estimating the upper limit value of the charging rate as the charging rate of the secondary battery;
When the calculated charging rate is equal to or lower than the lower limit value of the charging rate, estimating the lower limit value of the charging rate as the charging rate of the secondary battery;
When the calculated charging rate indicates a value between the charging rate less than the upper limit value and the charging rate lower limit value, the calculated charging rate at the second time is determined as the charging rate of the secondary battery. And a step of estimating as a charging rate. A charging rate estimation method for estimating a charging rate of a secondary battery in operation,
  Using the measured current and measured voltage of the secondary battery at a first time to calculate the charging rate of the secondary battery at the first time;
  Calculating the charge rate of the secondary battery at the second time using the measured current and the measured voltage of the secondary battery at a second time that is a time after the first time;
  Calculating a charge rate change amount by subtracting the charge rate at the first time from the charge rate at the second time;
  Calculating an integrated value of actually measured currents due to charging / discharging of the secondary battery from the first time to the second time;
  A step of calculating a full charge capacity of the secondary battery at the second time by dividing the integrated value of the current by the charge rate change amount;
  Estimating the charging rate of the secondary battery using the full charge capacity of the secondary battery and the integrated value of the measured current due to charging and discharging of the secondary battery;
  Have
  The first time is a time when the measured temperature or measured current of the secondary battery is within a predetermined range;
  The second time is a time during which the measured temperature or measured current of the secondary battery does not exceed a predetermined range between the first time and the time.
  The charge rate estimation method characterized by the above-mentioned. A charging rate estimation method for estimating a charging rate of a secondary battery in operation,
  Using the measured current and measured voltage of the secondary battery at a first time to calculate the charging rate of the secondary battery at the first time;
  Calculating the charge rate of the secondary battery at the second time using the measured current and the measured voltage of the secondary battery at a second time that is a time after the first time;
  Calculating a charge rate change amount by subtracting the charge rate at the first time from the charge rate at the second time;
  Calculating an integrated value of actually measured currents due to charging / discharging of the secondary battery from the first time to the second time;
  A step of calculating a full charge capacity of the secondary battery at the second time by dividing the integrated value of the current by the charge rate change amount;
  Estimating a function indicating a relationship between time and full charge capacity from full charge capacities of a plurality of secondary batteries calculated at different times;
  The full charge capacity of the secondary battery at the current time is identified with reference to the estimated function, and charging of the secondary battery is performed using the full charge capacity and the integrated value of the measured current due to charge / discharge of the secondary battery. Estimating the rate and
  Have
  In the step of estimating the function, the difference between the full charge capacity of the secondary battery calculated at a different time and the full charge capacity of the secondary battery calculated at the previous time or the full charge capacity indicated by the estimated function The difference does not exceed a predetermined threshold is used for the estimation of the function
  The charge rate estimation method characterized by the above-mentioned. A charging rate estimation method for estimating a charging rate of a secondary battery in operation,
  Using the measured current and measured voltage of the secondary battery at a first time to calculate the charging rate of the secondary battery at the first time;
  Calculating the charge rate of the secondary battery at the second time using the measured current and the measured voltage of the secondary battery at a second time that is a time after the first time;
  Calculating a charge rate change amount by subtracting the charge rate at the first time from the charge rate at the second time;
  Calculating an integrated value of actually measured currents due to charging / discharging of the secondary battery from the first time to the second time;
  A step of calculating a full charge capacity of the secondary battery at the second time by dividing the integrated value of the current by the charge rate change amount;
  Periodically estimating a function indicating the relationship between time and full charge capacity from the full charge capacity of a plurality of secondary batteries calculated at different times;
  The full charge capacity of the secondary battery at the current time is identified with reference to the estimated function, and using the full charge capacity and the integrated value of the measured current due to charging / discharging of the secondary battery, Estimating the charging rate and
  Monitoring a change in a coefficient of time in the estimated function, and issuing a warning if the change in the coefficient is equal to or greater than a predetermined threshold;
  The charging rate estimation method characterized by having. A computer for a charging rate estimation device that estimates the charging rate of a secondary battery in operation,
Using the measured current and measured voltage of the secondary battery at the first time, the charging rate of the secondary battery at the first time is calculated, and a second time that is later than the first time. A charge rate calculation unit that calculates the charge rate of the secondary battery at the second time using the measured current and measured voltage of the secondary battery at the time of
Charge rate change amount calculation for calculating the charge rate change amount by subtracting the charge rate at the first time calculated by the charge rate calculation unit from the charge rate at the second time calculated by the charge rate calculation unit. Part,
A current value integrating unit that calculates an integrated value of measured currents due to charging / discharging of the secondary battery from the first time to the second time;
The full charge capacity of the secondary battery at the second time is calculated by dividing the integrated value of the current calculated by the current value integrating unit by the charging rate change calculated by the charging rate change calculating unit. Full charge capacity calculator,
Using the full charge capacity calculated by the full charge capacity calculation unit and the integrated value of the measured current due to charge / discharge of the secondary battery, function as a charge rate estimation unit that estimates the charge rate of the secondary battery ,
The charging rate estimation unit
Using the full charge capacity calculated by the full charge capacity calculation unit, the integrated value of the measured current due to charging / discharging of the secondary battery, and the error of the measured current, the upper limit value and the lower limit value of the charging rate of the secondary battery are calculated. Operate,
When the charging rate calculated by the charging rate calculation unit is equal to or higher than the upper limit value of the charging rate, the upper limit value of the charging rate is estimated as the charging rate of the secondary battery,
When the charging rate calculated by the charging rate calculation unit is equal to or lower than the lower limit value of the charging rate, the lower limit value of the charging rate is estimated as the charging rate of the secondary battery,
When the charge rate calculated by the charge rate calculation unit indicates a value between the charge rate less than the upper limit value and the lower limit value of the charge rate, the charge at the second time calculated by the charge rate calculation unit The rate is estimated as the charging rate of the secondary battery
A program characterized by that . A computer for a charging rate estimation device that estimates the charging rate of a secondary battery in operation,
  Using the measured current and measured voltage of the secondary battery at the first time, the charging rate of the secondary battery at the first time is calculated, and a second time that is later than the first time. A charge rate calculation unit that calculates the charge rate of the secondary battery at the second time using the measured current and measured voltage of the secondary battery at the time of
  Charge rate change amount calculation for calculating the charge rate change amount by subtracting the charge rate at the first time calculated by the charge rate calculation unit from the charge rate at the second time calculated by the charge rate calculation unit. Part,
  A current value integrating unit that calculates an integrated value of measured currents due to charging / discharging of the secondary battery from the first time to the second time;
  The full charge capacity of the secondary battery at the second time is calculated by dividing the integrated value of the current calculated by the current value integrating unit by the charging rate change calculated by the charging rate change calculating unit. Full charge capacity calculator,
  A charge rate estimation unit that estimates the charge rate of the secondary battery using the full charge capacity calculated by the full charge capacity calculation unit and the integrated value of the measured current due to charging and discharging of the secondary battery
  Function as
  The first time is a time when the measured temperature or measured current of the secondary battery is within a predetermined range;
  The second time is a time during which the measured temperature or measured current of the secondary battery does not exceed a predetermined range between the first time and the time.
  A program characterized by that. A computer for a charging rate estimation device that estimates the charging rate of a secondary battery in operation,
  Using the measured current and measured voltage of the secondary battery at the first time, the charging rate of the secondary battery at the first time is calculated, and a second time that is later than the first time. A charge rate calculation unit that calculates the charge rate of the secondary battery at the second time using the measured current and measured voltage of the secondary battery at the time of
  Charge rate change amount calculation for calculating the charge rate change amount by subtracting the charge rate at the first time calculated by the charge rate calculation unit from the charge rate at the second time calculated by the charge rate calculation unit. Part,
  A current value integrating unit that calculates an integrated value of measured currents due to charging / discharging of the secondary battery from the first time to the second time;
  The full charge capacity of the secondary battery at the second time is calculated by dividing the integrated value of the current calculated by the current value integrating unit by the charging rate change calculated by the charging rate change calculating unit. Full charge capacity calculator,
  A function estimation unit that estimates a function indicating the relationship between time and full charge capacity from the full charge capacity of a plurality of secondary batteries calculated at different times by the full charge capacity calculation unit;
  Identify the full charge capacity of the secondary battery at the current time with reference to the function estimated by the function estimation unit, using the full charge capacity and the integrated value of the measured current by charging and discharging the secondary battery, Charge rate estimator for estimating the charge rate of secondary batteries
  Function as
  The function estimation unit indicates a difference between the full charge capacity of the secondary battery calculated at the previous time among the full charge capacities of the secondary battery calculated at different times by the full charge capacity calculation unit or an estimated function. A function whose difference from the full charge capacity does not exceed a predetermined threshold is used for the estimation of the function.
  A program characterized by that. A computer for a charging rate estimation device that estimates the charging rate of a secondary battery in operation,
  Using the measured current and measured voltage of the secondary battery at the first time, the charging rate of the secondary battery at the first time is calculated, and a second time that is later than the first time. A charge rate calculation unit that calculates the charge rate of the secondary battery at the second time using the measured current and measured voltage of the secondary battery at the time of
  Charge rate change amount calculation for calculating the charge rate change amount by subtracting the charge rate at the first time calculated by the charge rate calculation unit from the charge rate at the second time calculated by the charge rate calculation unit. Part,
  A current value integrating unit that calculates an integrated value of measured currents due to charging / discharging of the secondary battery from the first time to the second time;
  The full charge capacity of the secondary battery at the second time is calculated by dividing the integrated value of the current calculated by the current value integrating unit by the charging rate change calculated by the charging rate change calculating unit. Full charge capacity calculator,
  A function estimation unit that periodically estimates a function indicating the relationship between time and full charge capacity from the full charge capacity of a plurality of secondary batteries calculated at different times by the full charge capacity calculation unit,
  Identify the full charge capacity of the secondary battery at the current time with reference to the function estimated by the function estimation unit, using the full charge capacity and the integrated value of the measured current by charging and discharging the secondary battery, A charge rate estimator for estimating the charge rate of the secondary battery,
  A warning unit that monitors a change in a coefficient of time in the function estimated by the function estimation unit and issues a warning when the change in the coefficient is equal to or greater than a predetermined threshold.
  Program to function as.

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