JP4984382B2 - Battery remaining capacity estimation system and remaining capacity estimation method - Google Patents

Description

This invention relates to a remaining capacity estimating system and charge estimating method of batteries, and more particularly to a remaining capacity estimation system and charge estimating method of rechargeable secondary batteries.

  Secondary batteries are used in various fields. For efficient operation of the secondary battery, it is necessary to accurately perform charge / discharge control of the secondary battery. Therefore, a method for estimating the remaining capacity (SOC: State of Charge) of the secondary battery with high accuracy is required.

  Conventionally, a current integration method of charge / discharge current has been known as a method for calculating the SOC. However, in such a current integration method, for example, in the case of a battery usage that does not fully charge (full charge), the LSB (least significant bit) of the arithmetic unit (CPU) for calculating the SOC or self There is a problem that there is a limit to improvement in estimation accuracy because an error due to a capacity drop due to discharge is greatly affected, or the dependence on current sensor accuracy is high.

  For this reason, a method has been proposed in which the estimation accuracy is improved by estimating the remaining capacity (SOC) of the battery using both the electromotive voltage (open voltage) and the current integrated value of the battery (for example, Patent Document 1). Specifically, a battery remaining capacity calculation method has been proposed in which a SOC correction parameter is determined based on the electromotive voltage of the battery, and the SOC based on current integration is corrected using the correction parameter.

  According to this remaining capacity calculation method, the correction amount due to the electromotive voltage increases in a region where the SOC estimation accuracy from the electromotive voltage is high, and the correction amount due to the electromotive voltage decreases in a region where the SOC estimation accuracy from the electromotive voltage is low. By determining the correction parameter, the remaining capacity of the battery can be estimated with high accuracy without depending on the charge / discharge pattern of the battery.

Similarly, as a method of calculating the remaining capacity using both the current integration and the output voltage of the secondary battery, the remaining capacity control method for correcting the charging efficiency η used for the remaining capacity estimation based on the current integration according to the output voltage Has been proposed (for example, Patent Document 2).
JP 2003-149307 A JP 2002-369391 A

  However, in general, in charge / discharge control of a secondary battery, charge / discharge control is performed so as to prioritize charging or prioritize discharging at the SOC control center value. Further, upper and lower limit values are set in the SOC management range including the control center value to prevent overcharge and overdischarge. Specifically, when the upper limit value of the SOC management range is exceeded, charging is restricted or prohibited, while when it falls below the lower limit value, control is performed to control or inhibit discharging.

  For this reason, in terms of ensuring safety in the entire system including the charge / discharge control system of the secondary battery, that is, avoiding overcharge or overdischarge of the secondary battery, it is related to the charge / discharge control as described above. It is desirable to estimate the remaining capacity in consideration of

  The present invention has been made to solve such problems, and the object of the present invention is to increase the remaining capacity estimation of the secondary battery by avoiding overcharge and overdischarge more stably. To do with precision.

  Another object of the present invention is to provide a control system and an estimation system that control or estimate a physical quantity controlled according to a control center value in consideration of safety in consideration of the control center value. .

  The battery remaining capacity estimation system according to the present invention is a battery remaining capacity estimation system in which charging / discharging is controlled in accordance with the remaining capacity, and includes a first estimation means, a second estimation means, and a third estimation. Means. The first estimating means calculates a first estimated value related to the remaining capacity of the battery based on the integrated input / output current value of the battery from the previous estimated remaining capacity value. The second estimating means calculates a second estimated value related to the remaining capacity of the battery based on a parameter representing the state of the battery. The third estimating means receives the first and second estimated values from the first and second estimating means, and determines the magnitude relationship between the first estimated value and the second estimated value, and the first and second The remaining capacity estimation value is generated by correcting the first estimation value based on the magnitude relationship between the estimated value of 2 and the control center value of the remaining capacity value.

  In the battery remaining capacity estimation system, the second estimated value (estimated SOC) based on the battery state (for example, battery electromotive voltage) is based on the first estimated value (provisional SOC) based on the input / output current integration in a short period. The remaining capacity can be estimated with high accuracy. Further, such a correction of the deviation is based on the magnitude relationship between the first and second estimated values, that is, whether the correction is performed on the side of promoting charge or discharge, and the remaining capacity in the charge / discharge control of the battery. This is performed in consideration of the magnitude relationship between the control center value of the value and the first and second estimated values, that is, whether the current battery state is in a preferred region of charging or discharging. Therefore, compared to the case where the deviation is corrected uniformly, overcharge and overdischarge can be avoided more stably, and the remaining capacity of the secondary battery can be estimated with high accuracy.

  Preferably, in the battery remaining capacity estimation system according to the present invention, the second estimation means calculates a second estimated value based on the electromotive voltage of the battery.

  In the battery remaining capacity estimation system, the second estimated value (estimated SOC) can be easily calculated based on the electromotive voltage of the battery.

  Preferably, in the battery remaining capacity estimation system according to the present invention, the third estimation means includes a control calculation unit, a control gain setting unit, and an estimated value output unit. The control calculation unit calculates the remaining capacity correction amount by a control calculation based on a deviation of the second estimated value from the first estimated value. The control gain setting unit performs control calculation based on the magnitude relationship between the first estimated value and the second estimated value, and the magnitude relationship between the first and second estimated values and the control center value of the remaining capacity value. The control gain used for the control calculation in the unit is set. The estimated value output unit generates a remaining capacity estimated value by adding the first estimated value from the first estimating means and the remaining capacity correction amount from the control calculation unit.

  In the battery remaining capacity estimation system, the control gain is reflected by reflecting the magnitude relationship between the first and second estimated values and the magnitude relationship between the control center value of the remaining capacity value and the first and second estimated values. Control for setting and correcting the deviation is performed. That is, since the remaining capacity correction amount is determined according to the product of the deviation and the control gain, it is not necessary to subdivide the setting of the control gain so that the control gain setting unit can be configured easily.

  More preferably, in the battery remaining capacity estimation system according to the present invention, the control gain setting unit is configured such that the first estimated value and the second estimated value are both control centers in a region where the first estimated value is larger than the second estimated value. The control gain when larger than the value is set smaller than the control gain when at least one of the first and second estimated values is less than or equal to the control center value, while the first estimated value is greater than the second estimated value. In a small region, the control gain when both the first and second estimated values are smaller than the control center value is smaller than the control gain when at least one of the first and second estimated values is greater than or equal to the control center value. Set.

  In the battery remaining capacity estimation system, in a region where the correction by the third estimating means is performed in the direction of lowering the remaining capacity estimated value (charging promotion side) (first estimated value> second estimated value region). When both the first and second estimated values are larger than the control center value, that is, when both indicate that discharge-side control is desirable, the control gain is set relatively small, so that overcharge prevention safety is achieved. Can be increased. Similarly, in the region where the correction by the third estimating means is performed in the direction of increasing the remaining capacity estimated value (discharge promotion side) (first estimated value <second estimated value region), the first and second When the estimated value is smaller than the control center value, that is, when both indicate that the charge side control is desirable, the control gain is set relatively small, so that the safety of overdischarge prevention can be improved.

  More preferably, in the battery remaining capacity estimation system according to the present invention, the control gain setting unit is configured such that the first estimated value is greater than the control center value in a region where the first estimated value is greater than the second estimated value. In the region where the first estimated value is smaller than the second estimated value while the control gain when the second estimated value is smaller than the control center value is set larger than the control gain in the other cases. The control gain when the first estimated value is smaller than the control center value and the second estimated value is larger than the control center value is set larger than the control gain in the other cases.

  In the battery remaining capacity estimation system, the control gain is set to be relatively large when the magnitude relationship between the first estimated value (provisional SOC) and the second estimated value (estimated SOC) is different from the control center value. By doing so, the remaining capacity correction amount can be increased, and the estimated remaining capacity value can be quickly brought close to the second estimated value (estimated SOC).

  Alternatively, preferably, in the battery remaining capacity estimation system according to the present invention, the third estimation means includes a correction amount setting unit and an estimated value output unit. The correction amount setting unit calculates the remaining capacity correction amount by referring to a predetermined map having the first estimated value and the second estimated value as inputs. The estimated value output unit generates a remaining capacity estimated value by adding the first estimated value from the first estimating unit and the remaining capacity correction amount from the correction amount setting unit. Further, in the predetermined map, a correction ratio defined by a ratio in which the deviation of the second estimated value with respect to the first estimated value is a denominator and the map value of the remaining capacity correction amount is a numerator is the first estimated value and the second estimated value. And the magnitude relation between the first and second estimated values and the control center value of the remaining capacity value.

  In the battery remaining capacity estimation system, the magnitude relationship between the first estimated value (provisional SOC) and the second estimated value (estimated SOC), the control center value of the remaining capacity value, and the first and second estimated values. A predetermined map that sets the remaining capacity correction amount reflecting the magnitude relationship between the first and second estimated values is configured, and correction according to the deviation between the first and second estimated values is performed. Therefore, the calculation load can be reduced as compared with the configuration in which the same correction is performed by the control calculation using the control gain set by the same map.

  Preferably, in the battery remaining capacity estimating system according to the present invention, the third estimating means calculates the remaining capacity correction amount by referring to a predetermined map having the first estimated value and the second estimated value as inputs. . Further, in the predetermined map, a correction ratio defined by a ratio in which the deviation of the second estimated value with respect to the first estimated value is a denominator and the difference between the map values of the remaining capacity estimated value and the first estimated value is a numerator is: It is set based on the magnitude relationship between the first estimated value and the second estimated value and the magnitude relationship between the first and second estimated values and the control center value of the remaining capacity value.

  In the battery remaining capacity estimation system, the magnitude relationship between the first estimated value (provisional SOC) and the second estimated value (estimated SOC), the control center value of the remaining capacity value, and the first and second estimated values. A predetermined map that directly calculates the remaining capacity estimated value reflecting the magnitude relationship is constructed, and correction according to the deviation between the first and second estimated values is performed. Accordingly, the calculation load can be reduced compared to a configuration in which the same correction is performed by control calculation using the control gain set by the similar map or by setting the remaining capacity correction amount by the similar map.

  More preferably, in the battery remaining capacity estimation system according to the present invention, in the predetermined map, in the region where the first estimated value is larger than the second estimated value, both the first and second estimated values are less than the control center value. The correction ratio when large is set to be smaller than the correction ratio when at least one of the first and second estimated values is equal to or less than the control center value, while the first estimated value is larger than the second estimated value. In a small region, the correction ratio when the first and second estimated values are both smaller than the control center value is greater than the correction ratio when at least one of the first and second estimated values is equal to or greater than the control center value. Set small.

  In the battery remaining capacity estimation system, in a region where the correction by the third estimating means is performed in the direction of lowering the remaining capacity estimated value (charging promotion side) (first estimated value> second estimated value region). When both the first and second estimated values are larger than the control center value, that is, when both indicate that discharge-side control is desirable, the correction ratio is set to be relatively small, so that overcharge prevention safety is achieved. Can be increased. Similarly, in the region where the correction by the third estimating means is performed in the direction of increasing the remaining capacity estimated value (discharge promotion side) (first estimated value <second estimated value region), the first and second When both of the estimated values are smaller than the control center value, that is, when both indicate that the charge side control is desirable, the correction ratio is set relatively small, so that the safety of overdischarge prevention can be improved.

  Alternatively, more preferably, in the battery remaining capacity estimation system according to the present invention, in the predetermined map, the first estimated value is larger than the control center value in a region where the first estimated value is larger than the second estimated value, In addition, the correction ratio when the second estimated value is smaller than the control center value is set to be larger than the correction ratio in other cases, while the first estimated value is smaller than the second estimated value. The correction ratio when the first estimated value is smaller than the control center value and the second estimated value is larger than the control center value is set larger than the correction ratio in the other cases.

  In the battery remaining capacity estimation system, the correction ratio is set to be relatively large when the magnitude relationship between the first estimated value (provisional SOC) and the second estimated value (estimated SOC) is different from the control center value. By doing so, the remaining capacity correction amount can be increased, and the estimated remaining capacity value can be quickly brought close to the second estimated value (estimated SOC).

  The battery remaining capacity estimation method according to the present invention is a battery remaining capacity estimation method in which charging / discharging is controlled according to the remaining capacity value, and includes first to third estimation steps. The first estimation step calculates a first estimated value related to the remaining capacity of the battery from the previous estimated value of the input / output current integrated value of the battery. The second estimating step calculates a second estimated value related to the remaining capacity of the battery based on the electromotive voltage of the battery. The third estimation step includes a magnitude relationship between the first estimation value and the second estimation value estimated in the first and second estimation steps, and the first and second estimation values and the remaining capacity value. The remaining capacity value is estimated by correcting the first estimated value based on the magnitude relationship with the control center value.

  In the battery remaining capacity estimation method, the second estimation based on the battery state (for example, the battery electromotive voltage) in the long term based on the first estimated value (provisional SOC) based on the input / output current integration in a short period. The remaining capacity can be estimated with high accuracy so as to correct the deviation from the value (estimated SOC). Further, such a correction of the deviation is based on the magnitude relationship between the first and second estimated values, that is, whether the correction is performed on the side of promoting charge or discharge, and the remaining capacity in the charge / discharge control of the battery. This is performed in consideration of the magnitude relationship between the control center value of the value and the first and second estimated values, that is, whether the current battery is in a preferred region of charging or discharging. Therefore, compared to the case where the deviation is corrected uniformly, overcharge and overdischarge can be avoided more stably, and the remaining capacity of the secondary battery can be estimated with high accuracy.

  Preferably, in the battery remaining capacity estimation method according to the present invention, in the second estimation step, the second estimated value is calculated based on the electromotive voltage of the battery.

  In the battery remaining capacity estimation method, the second estimated value (estimated SOC) can be easily calculated based on the electromotive voltage of the battery.

  Preferably, in the battery remaining capacity estimating method according to the present invention, the third estimating step includes a magnitude relationship between the first estimated value and the second estimated value, and the first and second estimated values and the remaining value. The step of setting the control gain based on the magnitude relation between the capacity value and the control center value, and the remaining capacity by the control calculation based on the deviation of the second estimated value from the first estimated value using the set control gain. Calculating a correction amount; and generating a remaining capacity estimated value by adding the first estimated value estimated in the first estimating step and the remaining capacity correction amount.

  In the battery remaining capacity estimating method, the control gain is reflected by reflecting the magnitude relationship between the first and second estimated values and the magnitude relationship between the control center value of the remaining capacity value and the first and second estimated values. Control for setting and correcting the deviation is performed. That is, since the remaining capacity correction amount is determined according to the product of the deviation and the control gain, it is not necessary to subdivide the setting of the control gain so that the control gain setting unit can be configured easily.

  Alternatively, preferably, in the battery remaining capacity estimating method according to the present invention, the third estimating step calculates the remaining capacity correction amount by referring to a predetermined map having the first estimated value and the second estimated value as inputs. And a step of generating a remaining capacity estimated value by adding the first estimated value estimated by the first estimating means and the calculated remaining capacity correction amount. In the predetermined map, a correction ratio defined by a ratio having a deviation of the second estimated value with respect to the first estimated value as a denominator and a map value of the remaining capacity correction amount as a numerator is the first estimated value and the second estimated value. It is set based on the magnitude relationship between the values and the magnitude relationship between the first and second estimated values and the control center value of the remaining capacity value.

  In the battery remaining capacity estimation method, the magnitude relationship between the first estimated value (provisional SOC) and the second estimated value (estimated SOC), the control center value of the remaining capacity value, and the first and second estimated values. A predetermined map that directly calculates the remaining capacity estimated value reflecting the magnitude relationship is constructed, and correction according to the deviation between the first and second estimated values is performed. Accordingly, the calculation load can be reduced compared to a configuration in which the same correction is performed by control calculation using the control gain set by the similar map or by setting the remaining capacity correction amount by the similar map.

  Preferably, in the battery remaining capacity estimating method according to the present invention, the third estimating step calculates the remaining capacity correction amount by referring to a predetermined map having the first estimated value and the second estimated value as inputs. Generating a capacity estimate. In the predetermined map, a correction ratio defined by a ratio in which the deviation of the second estimated value with respect to the first estimated value is a denominator and the difference between the map values of the remaining capacity estimated value and the first estimated value is a numerator is Is set based on the magnitude relationship between the estimated value and the second estimated value, and the magnitude relationship between the first and second estimated values and the control center value of the remaining capacity value.

  In the battery remaining capacity estimation method, the magnitude relationship between the first estimated value (provisional SOC) and the second estimated value (estimated SOC), the control center value of the remaining capacity value, and the first and second estimated values. A predetermined map that directly calculates the remaining capacity estimated value reflecting the magnitude relationship is constructed, and correction according to the deviation between the first and second estimated values is performed. Accordingly, the calculation load can be reduced compared to a configuration in which the same correction is performed by control calculation using the control gain set by the similar map or by setting the remaining capacity correction amount by the similar map.

  An estimation system according to the present invention is a control amount estimation system controlled with a predetermined control center value, and includes first estimation means, second estimation means, and estimated value correction means. The first estimating means calculates a first estimated value related to the controlled variable based on the first information. The second estimating means calculates a second estimated value related to the controlled variable independently of the first estimating means based on the second information. The estimated value correcting means receives the first and second estimated values from the first and second estimating means, and determines the magnitude relationship between the first estimated value and the second estimated value, and the first and second estimated values. An estimated value of the controlled variable is generated by correcting the first estimated value in accordance with the correction priority defined based on the magnitude relationship between the estimated value and the control center value.

  In the estimation system, the deviation between the first and second estimated values can be corrected according to the correction priority based on the correlation between the first and second estimated values and the control center value. Therefore, the control amount controlled with the control center value is more stable in entering the unfavorable region of the control amount than the configuration in which the deviation between the first and second estimated values is uniformly corrected. Therefore, it can be estimated with high accuracy.

  A control system according to the present invention is a control system that performs control so that a predetermined control amount to be controlled matches a target value, and includes a deviation calculation unit, a control calculation unit, and a control gain setting unit. The deviation calculation unit calculates a deviation between the current value of the control amount and the target value. The correction amount is calculated by the control calculation unit and the control calculation based on the deviation. The control gain setting unit variably sets the control gain used for the control calculation in the control calculation unit according to the correction priority defined based on the correlation between the current value and the target value. The correction amount calculated by the control calculation unit is fed back to the operation input to be controlled.

  In the above control system, since the control gain can be variably set according to the correction priority based on the correlation between the target value and the current value, the control amount to be controlled is not preferable as compared with the configuration in which the control gain is uniformly set. It is possible to stably avoid entering the region and perform more stable control.

  Preferably, the control system according to the present invention further includes target value setting means for setting a target value according to the state of the controlled object. Further, the control amount is further controlled with a control center value independent of the target value, and the control gain setting unit determines the magnitude relationship between the target value and the current value, as well as the target value, the current value, and the control center value. A correction priority is set for each of a plurality of areas defined based on the magnitude relationship, and the control gain is set to a relatively large value in an area where the correction priority is relatively high.

  In the above control system, when the control amount is controlled with the control center value, the control priority value is more reliably entered into the unfavorable region by reflecting the magnitude relationship with the control center value in the correction priority. Can be avoided.

  According to the remaining capacity estimation system and remaining capacity estimation method of the present invention, the remaining capacity estimation of the secondary battery can be performed with high accuracy while avoiding overcharge and overdischarge more stably.

  According to the estimation system of the present invention, it is possible to estimate the control amount controlled with the control center value with high accuracy while more stably avoiding that the control amount enters an unfavorable region.

  According to the control system of the present invention, since the control gain can be variably set according to the correction priority based on the correlation between the target value and the current value, the control target is controlled as compared with the configuration in which the control gain is uniformly set. More stable control can be performed by stably avoiding entering the region where the amount is not preferable.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the following, the same or corresponding parts in the drawings will be denoted by the same reference numerals, and detailed description thereof will not be repeated.

[Embodiment 1]
FIG. 1 is a block diagram illustrating a configuration of a secondary battery remaining capacity estimation system 100 according to Embodiment 1 of the present invention.

  Referring to FIG. 1, the remaining capacity estimation system 100 operates in a predetermined cycle, and the SOC (remaining capacity estimation value) calculated last time, that is, one cycle before, the actual measurement voltage Vb from the previous estimation time to the present time, Based on the measured current Ib and the measured temperature Tb, the current SOC is calculated.

  The actually measured voltage Vb and the actually measured current Ib are respectively detected by a voltage sensor and a current sensor (not shown) provided at the output terminal of the secondary battery (not shown). The measured current Ib corresponds to the input / output current of the secondary battery. Similarly, the actually measured temperature Tb is also detected by a temperature sensor provided in the secondary battery.

  The remaining capacity estimation system 100 includes a provisional SOC calculation unit 10 that calculates a first estimated value #SOCa of a remaining capacity based on an integrated current value, and an electromotive voltage estimation unit 20 that estimates an electromotive voltage of a secondary battery based on a battery state. An estimated SOC calculating unit 30 that estimates the remaining capacity based on the estimated voltage value by the electromotive voltage estimating unit 20, and a final remaining capacity estimated value SOC based on the estimated values by the provisional SOC calculating unit 10 and the estimated SOC calculating unit 30 And an SOC calculation unit 40 for calculating.

  A charge / discharge control system (not shown) having control characteristics as described in FIGS. 2 and 3 is provided for a secondary battery (not shown) to be subjected to SOC calculation by the remaining capacity estimation system 100. It shall be.

  Referring to FIG. 2, charge / discharge control based on remaining capacity estimation value SOC by remaining capacity estimation system 100 shown in FIG. 1 is executed by a charge / discharge control system for a secondary battery (not shown). That is, the charge / discharge operation is controlled so that the discharge operation is given priority in the SOC> Sc region and the charge operation is given priority in the SOC <Sc region, with the SOC control center value Sc as a boundary.

  Further, as shown in FIG. 3, a SOC management range including the control center value Sc is provided. For example, on the discharge side, in the normal region where SOC ≧ S1, a fixed limit value is set in consideration of the output density of the battery, etc., whereas when the SOC falls below the control value S1, the discharge amount is limited, Further, when the SOC falls below the lower limit value S0 (S0 <S1), discharging is prohibited.

  Similarly, on the charging side, in the normal region where SOC ≦ S2, there is a fixed limit value in consideration of the charging capacity of the battery, while in the range where SOC exceeds S2 (SOC> S2), the amount of charge When the SOC exceeds the upper limit S3 (S3> S2), charging is prohibited.

  Referring to FIG. 1 again, provisional SOC calculation unit 10 obtains the first estimated value related to the remaining capacity estimation by adding the sum of integration unit 15 that integrates actual measurement current Ib, the output of integration unit 15 and the previously calculated SOC. And an adder 17 for outputting as #SOCa. In the following, estimated value #SOCa by provisional SOC calculation unit 10 is also referred to as “provisional SOC”. In other words, the provisional SOC is an estimated value related to the remaining capacity based on the integrated value of input / output batteries to the secondary battery.

  The electromotive voltage estimation unit 20 includes a voltage drop calculation unit 22, a polarization voltage calculation unit 24, and an addition unit 26. The voltage drop calculation unit 22 calculates the amount of voltage drop due to the internal resistance in the secondary battery according to the measured temperature Tb and the measured current Ib. For example, the change in the internal resistance corresponding to the parameter of the actually measured temperature Tb is stored in advance as a map, and this voltage drop amount can be estimated by the product of the internal resistance estimated value obtained by referring to the map and the actually measured current Ib.

  The polarization voltage calculator 24 estimates the polarization voltage based on the measured temperature Tb and the measured current Ib. The estimation of the polarization voltage can also be performed by creating a map using the measured temperature Tb and the measured current Ib as parameters and referring to the map. The adding unit 26 subtracts the voltage drop amount and the polarization voltage amount calculated by the voltage drop calculation unit 22 and the polarization voltage calculation unit 24 from the actual measurement voltage Vb, thereby estimating the electromotive voltage (open voltage) of the secondary battery. #VOC is calculated.

  Note that the measured temperature Tb, the measured current Ib, and the measured voltage Vb used in the electromotive voltage estimation unit 20 may be average values during a period from the previous remaining capacity estimation to the current remaining capacity estimation, for example. .

  Based on the electromotive voltage #VOC estimated by the electromotive force estimation unit 20, the estimated SOC calculation unit 30 calculates a second estimated value #SOCb related to the remaining capacity estimation. Hereinafter, this estimated value #SOCb is also referred to as estimated SOC. Hereinafter, estimated value #SOCb by estimated SOC calculation unit 30 is also referred to as “estimated SOC”. That is, the estimated SOC is an estimated value related to the remaining capacity based on the battery state.

  In this embodiment, a configuration in which the estimated SOC based on the battery state is obtained according to the battery electromotive voltage by a method other than the input / output current integration is illustrated, but the calculation of the estimated SOC is limited to such an example. It is not something. For example, the estimated SOC may be calculated using the battery internal pressure. That is, the estimated SOC can be obtained by appropriately using state parameters such as battery voltage, current, temperature, and internal pressure according to the type of secondary battery.

  The estimated SOC calculation unit 30 has a map reflecting the correspondence between the electromotive voltage and the SOC, for example, as shown in FIG. By obtaining a map value corresponding to the electromotive voltage estimated value #VOC by referring to the map, the estimated SOC (#SOCb) can be calculated in the range of 0 (%) to 100 (%).

  Here, as shown in FIG. 4, in the region where the SOC exceeds 100 (%), the electromotive voltage (open voltage) itself decreases from the peak value. For this reason, if the SOC is further overcharged in the region where 100% is exceeded, the charge / discharge control system of the secondary battery further promotes the charge due to the decrease in the estimated SOC accompanying the decrease in the electromotive voltage, and the overcharge is There is a risk of further progress. That is, it turns out that there is a risk that the charge / discharge control system becomes a divergent system.

  Therefore, in the remaining charge / discharge estimation calculation system according to the embodiment of the present invention, as described in detail below, the SOC calculation unit 40 causes the magnitude relationship between the provisional SOC (#SOCa) and the estimated SOC (#SOCb) and The SOC is calculated by calculating the SOC correction amount ΔSOC based on the estimated SOC and the magnitude relationship between the estimated SOC and the SOC control center value Sc, and correcting the provisional SOC with the correction amount ΔSOC.

  The SOC calculation unit 40 includes a subtraction unit 45, a control gain setting unit 50, a control calculation unit 60, and an addition unit 70.

  Subtraction unit 45 calculates deviation # ΔSOC of estimated SOC (#SOCb) with respect to provisional SOC (#SOCa). That is, it is defined by # ΔSOC = # SOCb− # SOCa.

  Control calculation unit 60 calculates SOC correction amount ΔSOC by a control calculation related to deviation # ΔSOC, for example, P control (proportional control) or PI control (proportional-integral control). For example, when the control calculation unit 60 performs the P control, the SOC correction amount ΔSOC is calculated using the control gain Gp set by the control gain setting unit 50 according to the following equation (1).

ΔSOC = Gp · # ΔSOC (1)
When PI control is performed by the control calculation unit 60, the SOC correction amount ΔSOC is calculated according to the following equation (2) using the control gains Gp and Gi set by the control gain setting unit 50.

(ΔSOC = Gp · # ΔSOC + Gi · ∫ (# ΔSOC) (2)
Here, ∫ (# ΔSOC) represents an integrated value of # ΔSOC from the time of activation of the remaining capacity estimation system 100.

  The control calculation by the control calculation unit 60 is performed so that the deviation Δ # SOC approaches 0, that is, based on the current integrated value in each estimation period, and in the long term, the estimated SOC (# ΔSOC ) To bring the estimated remaining capacity value (SOC) closer. Adder 70 calculates final remaining capacity estimated value SOC by adding provisional SOC (#SOCa) and SOC correction amount ΔSOC, that is, according to the following equation (3).

SOC = # SOCa + ΔSOC (3)
In the remaining capacity estimation system according to the first embodiment of the present invention, control gain setting is performed in consideration of the charge / discharge control method described in FIGS. 2 and 3 and the decrease in electromotive voltage in the overcharge region shown in FIG. In unit 50, a control gain is set using a map 50 # described below.

  Map 50 # is a two-dimensional map with provisional SOC (#SOCa) and estimated SOC (#SOCb) as inputs, and the output map value is a control gain value. This control gain value generally indicates the values of the control gains Gp, Gi, etc. in FIG.

  Referring to FIG. 5, map 50 # stored in control gain setting unit 50 is divided by a characteristic line 150 where both provisional SOC (#SOCa) and estimated SOC (#SOCb) are 1: 1. Divided into 160 and 170.

  Region 160 is a region where the provisional SOC is larger than the estimated SOC (#SOCa> #SOCb). In this region, the deviation # ΔSOC is negative (<0), so the SOC correction amount ΔSOC is also set negative (<0). That is, the SOC calculation unit 40 corrects the direction in which the SOC is relatively lowered, that is, the direction in which charging is promoted.

  On the other hand, the region 170 is a region where the provisional SOC is smaller than the estimated SOC (#SOCa <#SOCb). In this region, the deviation # ΔSOC is positive (> 0), so the SOC correction amount ΔSOC is also set to positive (> 0). That is, the SOC calculation unit 40 corrects the direction in which the SOC is relatively increased, that is, the direction in which the discharge is accelerated.

  As shown in FIG. 6, each of regions 160 and 170 is further subdivided according to the magnitude relationship between provisional SOC (#SOCa) and estimated SOC (#SOCb) and SOC control center value Sc. Specifically, in region 160, both provisional SOC and estimated SOC are larger than control center value Sc (#SOCa> Sc and # ΔSOCb> Sc), and both provisional SOC and estimated SOC are control center values. Region A2 smaller than Sc (#SOCa <Sc and # ΔSOCb <Sc), and provisional SOC is larger than control center value Sc, while estimated SOC is smaller than control center value Sc (#SOCa> Sc and #SOCb < Sc) Divided into area A3.

  Similarly, in region 170, both provisional SOC and estimated SOC are smaller than control center value Sc (#SOCa <Sc and # ΔSOCb <Sc), and both provisional SOC and estimated SOC are smaller than control center value Sc. Is larger (#SOCa> Sc and # ΔSOCb> Sc) and the estimated SOC is larger than the control center value Sc while the provisional SOC is smaller than the control center value Sc (#SOCa <Sc and #SOCb> Sc). Divided into region B3.

  The map value, that is, the control gain value in the control gain setting unit 50 is set in g1, g2, and g3 for each of the regions A1 to A3 and the regions B1 to B3. This map value generally indicates the values of the control gains Gp, Gi, etc. in FIG.

  In the area A1, both the provisional SOC and the estimated SOC are larger than the control center value Sc, indicating that it is desirable to control both to the discharge side. On the other hand, however, the SOC correction amount obtained by multiplying the deviation Δ # SOC by the control gain value is negative (ΔSOC <0) because of the magnitude relationship between the estimated SOC and the estimated SOC. Since correction when ΔSOC <0 acts on the side that promotes charging, it is safer to prevent overcharge by setting the control gain value g1 in this region A1 to 0 or a very small value and reducing the absolute value of the SOC correction amount ΔSOC. It is preferable at the point which improves property.

  Similarly, also in the region B1, both the provisional SOC and the estimated SOC are smaller than the control center value Sc, indicating that it is desirable that both are controlled to the charging side. On the other hand, however, because of the magnitude relationship between the estimated SOC and the estimated SOC, the SOC correction amount obtained by multiplying the deviation Δ # SOC by the control gain value is positive (ΔSOC> 0). Since correction with ΔSOC> 0 acts on the side that promotes discharge, overdischarge is prevented in this region B1 by setting the control gain value g1 to 0 or a very small value and reducing the absolute value of the SOC correction amount ΔSOC. This is preferable in terms of improving safety.

  Further, in region A2, both the provisional SOC and the estimated SOC are smaller than the control center value Sc, indicating that it is desirable to control to the charge side. In this region, SOC correction is performed from Δ # SOCa> Δ # SOCb. The amount is negative (ΔSOC <0). Since the correction when ΔSOC <0 acts on the side that promotes charging, in the region A2, the deviation Δ # SOC is made close to 0 without special consideration of safety, that is, the risk of overdischarge and overcharge. The gain setting may be performed in consideration of controllability. Therefore, the control gain value g2 in the region A2 is set to be relatively larger than the control gain value in the region A1 (that is, g2> g1).

  Similarly, in region B2, both the provisional SOC and the estimated SOC are larger than the control center value Sc, indicating that it is desirable to control to the discharge side. In this region, the SOC is more than Δ # SOCa <Δ # SOCb. The correction amount is positive (ΔSOC> 0). Since the correction when ΔSOC> 0 acts on the side that promotes discharge, the gain setting in consideration of the controllability is made so that the deviation Δ # SOC approaches 0 without special consideration of safety even in the region B2. Just do it. Therefore, the control gain value g2 in the region B2 is set relatively larger than the control gain value in the region B2 (that is, g2> g1).

  On the other hand, in the region A3, it is indicated that the estimated SOC is preferably smaller than the control center value Sc and controlled to the charging side, while the provisional SOC is larger than the control center value Sc. In order to shift the SOC to the charge priority side, it is highly necessary to set the SOC correction amount ΔSOC to the negative side. Therefore, in region A3, deviation Δ # SOC is negative from Δ # SOCa> Δ # SOCb (Δ # SOC <0), so that the control gain value g3 in region A3 is the control gain value in regions A1 and A2. (That is, g3> g2> g1).

  Similarly, in the region B3, it is indicated that it is desirable to control the estimated SOC to be larger than the control center value Sc on the discharge side, while the provisional SOC is smaller than the control center value Sc. In order to shift to the discharge priority side, it is highly necessary to set the SOC correction amount ΔSOC to the positive side. Therefore, in region B3, deviation Δ # SOC is more positive than Δ # SOCa <Δ # SOCb (Δ # SOC> 0), so the control gain value g3 in region B3 is the control gain value in regions A1 and A2. (That is, g3> g2> g1).

  In the map configuration example of FIG. 6, the control gain values g1 to g3 in the regions A1 to A3 and the regions B1 to B3 are common to the regions 160 and 170, respectively. Different control gain values may be used. For example, with respect to the control gain values ga1, ga2 and ga3 (ga3> ga2> ga1) in the regions A1, A2 and A3, the control gain values gb1, gb2 and gb3 (gb3) in the regions B1, B2 and B3, respectively. > Gb2> gb1) may be used.

  In addition, since a sudden change in the control gain value may not be preferable at the boundary portion of each region, as shown in FIG. 7, the map is such that the control gain value gradually changes according to a constant rate at the boundary portion. May be configured.

  For example, FIG. 7A shows the setting of the control gain value at the boundary between the regions B1 and B3. As shown in FIG. 7 (a), in the predetermined section 180 including the control center value Sc, the map is set so that the control gain value gradually increases from g1 to g3 as the estimated SOC (#SOCb) increases. It may be configured.

  FIG. 7B shows the setting of the control gain value at the boundary between the areas A1 and B2. As shown in FIG. 7B, the deviation Δ # SOC (# SOCb− # SOCa) increases in a predetermined section 185 across the characteristic line 150 at the boundary between the area A1 and the area B2, that is, from the characteristic line 150. The map may be configured so that the control gain value gradually increases from g1 to g2 according to the distance.

  Further, in each of the regions A1 to A3 and the regions B1 to B3, the control gain value is not set to a constant value in the regions other than the boundary portion, but the control gain value is continuously set according to #SOCa, #SOCb, etc. It is also possible to change the configuration to

  Moreover, you may provide a dead zone about the transition conditions between each area | region. For example, the transition condition from region B2 (#SOCa <#SOCb) across characteristic line 150 to region A1 (#SOCa> #SOCb) is expressed by the following equation (3), and the transition condition from region A1 to region B2 is 4) It can be set as a formula.

#SOCa># SOCb + Δs1 (3)
#SOCa <# SOCb-Δs2 (4)
Similarly, the transition condition from the region A2 (#SOCa <Sc) to the region A3 (#SOCa> Sc) across the control center value Sc is expressed by the following equation (5), and the transition condition from the region A3 to the region A2 is expressed as follows. (6) Equation #SOCa> Sc + Δs3 (5)
#SOCa <Sc-Δs4 (6)
Furthermore, for example, Δs1 ≠ Δs2 between the above expressions (3) and (4), and Δs3 ≠ Δs4 between the above expressions (5) and (6), and hysteresis may be provided for transition between regions. . Note that Δs1 to Δs4 may be set in consideration of control stability based on experimental data or the like.

  Here, the correspondence between the configuration according to the first embodiment and the configuration of the present invention will be described. The provisional SOC calculation unit 10 corresponds to the “first estimation means” in the present invention, and the estimated SOC calculation unit 30 (FIG. 1). ) Corresponds to the “second estimation means” in the present invention, and the SOC calculation unit 40 (FIG. 1) corresponds to the “third estimation means” in the present invention. Adder 70 corresponds to the “estimated value output unit” in the present invention.

  FIG. 8 is a flowchart showing the remaining capacity estimation method in secondary battery remaining capacity estimation system 110 according to Embodiment 1 of the present invention described above.

  Referring to FIG. 8, in the remaining capacity estimation method according to the embodiment of the present invention, a remaining capacity estimation (SOC calculation) control routine described below is executed at predetermined intervals.

  When the remaining capacity estimation control routine is executed, the provisional SOC (#SOCa) is calculated by the provisional SOC calculation unit 10 (FIG. 1) based on the input / output current integration from the previous calculation SOC (step S100).

  Subsequently, the estimated SOC (#SOCb) based on the battery state is calculated by the electromotive force estimation unit 20 and the estimated SOC calculation unit 30 shown in FIG. 1 by referring to a map reflecting the characteristic line as shown in FIG. (Step S110).

  Further, using the provisional SOC (#SOCa) and the estimated SOC (#SOCb) calculated in steps S100 and S110, respectively, the magnitude relationship between the provisional SOC and the estimated SOC, as well as the provisional SOC, the estimated SOC, and the SOC control center value. By correcting the provisional SOC based on the magnitude relationship with Sc, the remaining capacity is estimated, that is, the SOC is calculated (step S120).

  In step S120, the control gain value is determined based on the relationship between the provisional SOC and the estimated SOC and the relationship between the provisional SOC and the estimated SOC and the control center value Sc by referring to the predetermined map described with reference to FIGS. Step S140 for calculating the SOC correction amount (ΔSOC) from the estimated SOC deviation # ΔSOC with respect to the provisional SOC by the control calculation (P control, PI control, etc.) using the control gain value determined in Step S130, and provisional SOC (# Step S150 for calculating a remaining capacity estimated value (SOC) by the sum of SOCa) and SOC correction amount (ΔSOC).

  Here, the correspondence between the flowchart of FIG. 8 and the configuration of the present invention will be described. Steps S100, S110, and S120 are “first estimation step”, “second estimation step”, and “third estimation”. Each step corresponds to “step”.

  As described above, in the remaining capacity estimation according to the first embodiment of the present invention, short-term current integration is based on provisional SOC based on input / output current integration and estimated SOC based on battery state (for example, battery electromotive voltage). In the long term, the remaining capacity can be estimated according to the battery state. In particular, in accordance with the magnitude relationship between the provisional SOC and the estimated SOC and the magnitude relationship with the control center value, the SOC correction amount (from the deviation of the provisional SOC and the estimated SOC is considered in consideration of the qualitative risk of overcharge and overdischarge. The control gain value for calculating (SOC) is variably set. Accordingly, overcharge and overdischarge can be avoided more stably, and the remaining capacity of the secondary battery can be estimated with high accuracy.

[Embodiment 2]
FIG. 9 is a block diagram showing a configuration of a secondary battery remaining capacity estimation system 110 according to Embodiment 2 of the present invention.

  Referring to FIG. 9, remaining capacity estimation system 110 according to Embodiment 2 includes SOC calculation unit 40 # instead of SOC calculation unit 40, as compared with remaining capacity estimation system 100 shown in FIG. It is different.

  SOC calculation unit 40 # includes an SOC correction amount setting unit 52 and an addition unit 70. The SOC correction amount setting unit 52 is configured with a map as shown in FIG. 10, and calculates the SOC correction amount ΔSOC based on the provisional SOC (#SOCa) and the estimated SOC (#SOCb). Adder 70 calculates the current remaining capacity estimated value (SOC) based on the sum of provisional SOC (#SOCa) from provisional SOC calculator 10 and SOC correction amount ΔSOC from SOC correction amount setting unit 52.

  Regarding the configuration of the other parts, that is, the provisional SOC calculation unit 10, the electromotive voltage estimation unit 20, and the estimated SOC calculation unit 30 relating to the calculation of the provisional SOC and the estimated SOC, the remaining capacity estimation system 100 shown in FIG. Since they are similar, detailed description will not be repeated. Further, the charge / discharge control (SOC management) of the secondary battery described with reference to FIGS. 2 and 3 is performed using the SOC estimated by the remaining capacity estimation system 110.

  Referring to FIG. 10, map 52 # constituting SOC correction amount setting unit 52 receives provisional SOC (#SOCa) and estimated SOC (#SOCb), as in map 51 # shown in FIG. Each of the regions 160 and 170 that are two-dimensional maps and have the characteristic line 150 as a boundary is divided into regions A1 to A3 and B1 to B3.

  Since the map value of map 52 # according to the second embodiment directly indicates the SOC correction amount ΔSOC, not the control gain value, a value corresponding to the multiplication value of control gain value (g1 to g3 in FIG. 6) and deviation # ΔSOC. It becomes. Therefore, in each region, the mesh based on the provisional SOC and the estimated SOC is further subdivided.

  For example, each map value is determined by the product of the corresponding control gain values g1 to g3 shown in FIG. 6 and the deviation # ΔSOC in each mesh in each of the regions A1 to A3 and B1 to B3.

  That is, if the correction ratio kc is defined with the deviation Δ # SOC as the denominator and the map value (that is, ΔSOC) as the numerator (kc = ΔSOC / Δ # SOC), the distribution of the correction ratio kc in each mesh is controlled in FIG. It is set similarly to the distribution of the gains g1 to g3. Note that the map value can be set so that the correction ratio kc gradually changes at the boundary between regions as described in FIG.

  In other words, SOC correction amount setting unit 52 uses map 52 # configured to have the functions of control gain setting unit 50 and control calculation unit 60 shown in FIG. 1 as provisional SOC (#SOCa) and estimated SOC (#SOCb ) To determine the SOC correction amount ΔSOC. Accordingly, the SOC correction amount ΔSOC by the SOC correction amount setting unit 52 is basically set in the same tendency as ΔSOC output from the control calculation unit 60 of FIG.

  FIG. 11 is a flowchart illustrating a remaining capacity estimation method in secondary battery remaining capacity estimation system 110 according to the second embodiment.

  Referring to FIG. 11, the remaining capacity estimation control routine according to the second embodiment executes steps S110 and S120 similar to the remaining capacity estimation control routine according to the first embodiment shown in FIG. Thereby, provisional SOC (#SOCa) and estimated SOC (#SOCb) are calculated by provisional SOC calculation unit 10 and estimated SOC calculation unit 30, respectively.

  In the remaining capacity estimation control routine according to the second embodiment, step S120 is performed based on the magnitude relationship between provisional S0C and estimation SOC and the relation between provisional SOC and estimation SOC and SOC control center value (Sc). Step S122 for determining the SOC correction amount ΔSOC with reference to FIG. 10 and a step for calculating the estimated remaining capacity (SOC) by the sum of the SOC correction amount ΔSOC obtained in Step S122 and the provisional SOC (#SOCa). S150.

  Thus, in the remaining capacity estimation according to the second embodiment, as in the remaining capacity estimation according to the first embodiment, the overcharge and the estimated SOC are overcharged according to the magnitude relation between the provisional SOC and the estimated SOC and the magnitude relation with the control center value. In consideration of the qualitative risk of overdischarge, the SOC correction amount (ΔSOC) for the deviation between the provisional SOC and the estimated SOC is variably set. Accordingly, overcharge and overdischarge can be avoided more stably, and the remaining capacity of the secondary battery can be estimated with high accuracy.

  In the remaining capacity estimation according to the second embodiment, the SOC correction amount (ΔSOC) can be obtained only by referring to the map without performing the control calculation in the control calculation unit 60 (FIG. 1). It is possible to reduce a calculation load on a calculation device (CPU or the like) that realizes the capacity estimation method. On the other hand, as described with reference to FIG. 10, it is necessary to subdivide the mesh of the map in order to reflect the deviation Δ # SOC in the map value.

[Embodiment 3]
FIG. 12 is a block diagram showing a configuration of a secondary battery remaining capacity estimation system 120 according to Embodiment 3 of the present invention.

  Referring to FIG. 12, the remaining capacity estimation system 120 according to the third embodiment is different from the remaining capacity estimation system 100 shown in FIG. 1 in that an SOC calculation unit 41 is provided instead of the SOC calculation unit 40. Different. Regarding the configuration of the other parts, that is, the provisional SOC calculation unit 10, the electromotive voltage estimation unit 20, and the estimated SOC calculation unit 30 relating to the calculation of the provisional SOC and the estimated SOC, the remaining capacity estimation system 100 shown in FIG. Since they are similar, detailed description will not be repeated. Further, charge / discharge control (SOC management) of the secondary battery described with reference to FIGS. 2 and 3 is performed using the SOC estimated by the remaining capacity estimation system 120.

  SOC calculation unit 41 includes an SOC calculation map 53 #. SOC calculation map 53 # is configured as shown in FIG. 13, and obtains an estimated remaining capacity (SOC) based on provisional SOC (#SOCa) and estimated SOC (#SOCb).

  Referring to FIG. 13, SOC calculation map 53 # is a two-dimensional map having provisional SOC (#SOCa) and estimated SOC (#SOCb) as inputs, similarly to map 50 # (FIG. 6), and Divided into regions A1 to A3 and B1 to B3. Further, each region is further subdivided with a mesh based on the provisional SOC and the estimated SOC. Each map value is determined by adding the temporary SOC (#SOCa) in the mesh to the map value (that is, the SOC correction amount ΔSCO) in the map 52 # of FIG.

  That is, the output value from SOC calculation map 53 # corresponds to (ΔSOCa + ΔSOC) in Embodiments 1 and 2, that is, the final remaining capacity estimation value (SOC). Therefore, the final SOC is calculated basically in the same manner as the remaining capacity estimation systems 110 and 120 according to the first and second embodiments.

  Therefore, if the correction ratio kc is defined with the deviation Δ # SOC as the denominator and the difference between the map value and the provisional SOC (SOC−ΔSOCa = ΔSOC) as the numerator, the distribution of the correction ratio kc in each mesh is as shown in FIG. It is set similarly to the distribution of the control gains g1 to g3. Note that the map value can be set so that the correction ratio kc gradually changes at the boundary between regions as described in FIG.

  FIG. 14 is a flowchart illustrating a remaining capacity estimation method according to the third embodiment.

  Referring to FIG. 14, the remaining capacity estimation control routine according to the third embodiment executes steps S110 and S120 similar to the remaining capacity estimation control routine according to the second embodiment shown in FIG. Thereby, provisional SOC (#SOCa) and estimated SOC (#SOCb) are calculated by provisional SOC calculation unit 10 and estimated SOC calculation unit 30, respectively.

  In the remaining capacity estimation control routine according to the third embodiment, step S120 is performed by referring to SOC calculation map 53 #, the magnitude relationship between provisional SOC and estimation SOC, and estimation SOC, provisional SOC, and SOC control center value Sc. Based on the relationship, the process includes step S124 for directly calculating the estimated remaining capacity (SOC).

  As described above, in the remaining capacity estimation according to the third embodiment as well, as in the remaining capacity estimation according to the first embodiment, overcharge and In consideration of the qualitative risk of overdischarge, the correction amount (SOC- # SOCa) for estimating the remaining capacity with respect to the deviation between the provisional SOC and the estimated SOC is variably set. Accordingly, overcharge and overdischarge can be avoided more stably, and the remaining capacity of the secondary battery can be estimated with high accuracy.

  In the remaining capacity estimation according to the third embodiment, compared with the remaining capacity estimation according to the second embodiment, the remaining capacity estimation (SOC) is performed only by referring to the map without performing the addition operation in the adding unit 70 (FIG. 9). Can be sought. Therefore, it is possible to further reduce the calculation load on the arithmetic device (CPU or the like) that realizes the remaining capacity estimation system and the remaining capacity estimation method. On the other hand, as described with reference to FIG. 13, it is necessary to further subdivide the mesh of the map in order to reflect the provisional SOC (#SOCa) in the map value, but the calculation can be performed accurately with a light load.

[Embodiment 4]
The estimation system described in the first to third embodiments can be applied not only to the estimation of the remaining capacity of the secondary battery but also to an estimation system for other physical quantities.

  FIG. 15 is a block diagram showing a configuration example of an estimation system 500 according to Embodiment 4 of the present invention. The estimation system 500 is based on the same method as the secondary battery remaining capacity estimation system according to the first to third embodiments, and various control amounts controlled with control center values other than the remaining capacity of the secondary battery. Is estimated. Such a control amount includes an inverter current and the like.

  Referring to FIG. 15, estimation system 500 includes a first estimation unit 510, a second estimation unit 520, and an estimated value correction unit 540.

  First estimation unit 510 calculates first estimated value #SVa based on estimation source data PD1. Second estimation unit 520 calculates second estimated value #SVb based on estimation source data PD2. Calculation of the estimated value by the first estimation unit 510 and the second estimation unit 520 is performed according to independent methods, but at least a part of the estimation source data PD1 and PD2 may overlap. Further, the calculation of the first estimated value #SVa by the first estimating unit 510 may reflect the estimated value SV in the past.

  Estimated value correcting unit 540 receives estimated values #SVa and #SVb from first estimating unit 510 and second estimating unit 520, and the magnitude relationship between estimated values #SVa and #SVb, as well as estimated values #SVa and #SVb. The estimated value SV of the control amount is generated by correcting the estimated value #SVa according to the correction priority defined based on the magnitude relationship between the SVb and the control center value Sc.

  That is, estimated values #SVa and #SVb in the estimation system of FIG. 15 correspond to provisional SOC (#SOCa) and estimated SOC (#SOCb) in the secondary battery remaining capacity estimation system according to Embodiments 1 to 3, respectively. To do. Estimated value correction unit 540 corresponds to SOC calculation units 40, 40 #, 41 in the secondary battery remaining capacity estimation system according to the first to third embodiments.

  Therefore, as the correction according to the correction priority in the estimated value correction unit 540, the control gain setting divided into the areas A1 to A3 and B1 to B3 shown in FIG. 6 and divided into areas as shown in FIG. This is realized by setting a correction value set value or a final estimated value including a correction amount divided for each region as shown in FIG. 13 using a similar table.

  By adopting such a configuration, the control amount is not preferable as compared with the configuration in which the deviation between the first and second estimated values is uniformly corrected for the control amount controlled with the control center value. It is possible to estimate with high accuracy while more stably avoiding entering the region.

  Alternatively, the variable setting of the control gain according to the first embodiment can be applied to a general closed loop control system.

  FIG. 16 is a block diagram showing a configuration example of a control system 600 according to the fourth embodiment of the present invention.

  Referring to FIG. 16, control system 600 includes control target 610, target value calculation unit 630, and feedback control unit 640. The estimation system 600 is a feedback loop system that controls the control amount SV of the control target 610 to the target value SVr. Control target 610 is, for example, an inverter, and the controlled variable corresponds to the output current of the inverter.

  The target value calculation unit 630 sets the target value SVr according to the information 620 indicating the operation state of the control target 610 or its load. On the other hand, for the control amount SV, the control center value Sc may be defined independently of the target value SVr.

  Feedback control unit 640 includes a subtraction unit 645, a control gain setting unit 650, and a control calculation unit 660.

  The subtraction unit 645 calculates a deviation ΔSV between the control value target value SVr and the current value SV, as in the subtraction unit 45 of FIG. The control gain setting unit 650 is configured in the same manner as the control gain setting unit 50 of FIG. 1, and is controlled by the control calculation unit 660 according to the correction priority defined based on the correlation between the current value Sv and the target value SVr. The control gain used for the control calculation is variably set. For example, control gain setting unit 650 is realized by a table in which provisional SOC (#SCOa) and estimated SOC (#SOCb) are replaced with current value SV and target value SVr of the control amount in the gain setting table shown in FIG. can do. That is, in the table, by dividing the regions A1 to A3 and B1 to B3 based on the magnitude relationship between the target value SVr and the current value SV and the magnitude relationship between the target value SVr, the current value SV and the control center value Sc, Correction priority will be defined.

  The control calculation unit 660 calculates the correction amount SU by control calculation (P control, PI control, etc.) using the control gain variably set by the control gain setting unit 650. Calculation of correction amount SU based on deviation ΔSV by control calculation unit 660 is performed in the same manner as calculation of SOC correction amount ΔSOC based on deviation # ΔSOC by control gain setting unit 60 in FIG. 1, and therefore detailed description will not be repeated. .

  The correction amount SU calculated by the control calculation unit 660 is reflected (that is, fed back) to the operation input of the control target 610 (corresponding to the switching duty ratio in the inverter, etc.), so that the control amount approaches the target value SVr. Is realized.

  With such a configuration, the control gain can be variably set according to the correction priority based on the correlation between the target value and the current value, so that the control amount is smaller than the configuration in which the control gain is uniformly set. It is possible to more stably avoid entering an unfavorable region and perform more stable control. In particular, when the control amount is controlled with a control center value, it is possible to more surely prevent the control amount from entering an unfavorable region by reflecting the magnitude relationship with the control center value in the correction priority. .

  Alternatively, as in the control system 600 # shown in FIG. 17, the target value SVr (control center) is similarly set in a configuration in which the target value SVr of the control amount is fixed and the target value SVr matches the control center value Sc. If the correction priority is determined according to the correlation between the value Sc) and the current value SV and the control gain for calculating the correction amount is variably set, the same effect as that of the control system 600 shown in FIG. 16 can be obtained. Can do.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

It is a block diagram which shows the structure of the remaining capacity estimation system of the secondary battery by Embodiment 1 of this invention. It is a figure explaining the relationship with the SOC control center value of charging / discharging control of a secondary battery. It is a figure explaining the restriction | limiting and prohibition of charge and discharge in charge / discharge control of a secondary battery. It is a conceptual diagram explaining the relationship between the open circuit voltage (electromotive voltage) and remaining capacity (SOC) of a secondary battery. It is a 1st figure explaining the structural example of the map which comprises the control gain setting part shown in FIG. FIG. 4 is a second diagram illustrating a configuration example of a map configuring the gain setting unit illustrated in FIG. 1. It is a figure explaining the gain setting between the area | regions of the map which comprises the control gain map setting part shown in FIG. It is a flowchart explaining the remaining capacity estimation method by Embodiment 1 of this invention. It is a block diagram explaining the remaining capacity estimation system by Embodiment 2 of this invention. It is a figure explaining the structural example of the map which comprises the SOC correction amount setting part shown in FIG. It is a flowchart explaining the remaining capacity estimation method by Embodiment 2 of this invention. It is a block diagram which shows the structure of the remaining capacity estimation system by Embodiment 3 of this invention. It is a figure which shows the structure of the map used as an SOC estimation part shown in FIG. It is a flowchart explaining the remaining capacity estimation method by Embodiment 3 of this invention. It is a block diagram explaining the structural example of the estimation system by Embodiment 4 of this invention. It is a block diagram explaining the 1st structural example of the control system by Embodiment 4 of this invention. It is a block diagram explaining the 2nd structural example of the control system by Embodiment 4 of this invention.

Explanation of symbols

  10 provisional SOC calculation unit, 15 integration unit, 17, 26, 70 addition unit, 20 electromotive voltage estimation unit, 22 voltage drop calculation unit, 24 polarization voltage calculation unit, 30 estimated SOC calculation unit, 40, 40 #, 41 SOC calculation Unit, 45 subtraction unit, 50 control gain setting unit, 51 # map (control gain), 52 # map (SOC correction amount), 52 SOC correction amount setting unit, 53 # SOC calculation map, 60 control calculation unit, 100, 110 , 120 remaining capacity estimation system, 150 characteristic line (provisional SOC = estimated SOC), 160, 170, A1 to A3, B1 to B3 regions, g1 to g3 control gain values, Gp, Gi control gain, Ib actual measurement current, Sc SOC Control center value, Tb measured temperature, Vb measured voltage, ΔSOC SOC correction amount, 510 first estimation unit, 520 second estimation unit, 540 Fixed value correction unit, 610 control target, 630 target value calculation unit, 640 feedback control unit, 645 subtraction unit, 650 control gain setting unit, 660 control calculation unit.

Claims (14)

A battery remaining capacity estimation system in which charging / discharging is controlled according to the remaining capacity,
First estimating means for calculating a first estimated value related to the remaining capacity of the battery based on the integrated input / output current value of the battery from the previous estimated remaining capacity value;
Second estimating means for calculating a second estimated value related to the remaining capacity of the battery based on a parameter representing the state of the battery;
Upon receiving the first and second estimation values from the first and second estimation means, a magnitude relationship between the first estimation value and the second estimation value, and the first and second estimation values Battery remaining capacity estimation system comprising: a third estimation unit that generates a remaining capacity estimation value by correcting the first estimation value based on a magnitude relationship between a value and a control center value of the remaining capacity value .   The battery remaining capacity estimation system according to claim 1, wherein the second estimation means calculates the second estimated value based on an electromotive voltage of the battery. The third estimating means includes
A control calculation unit that calculates a remaining capacity correction amount by a control calculation based on a deviation of the second estimated value with respect to the first estimated value;
Based on the magnitude relationship between the first estimated value and the second estimated value and the magnitude relationship between the first estimated value and the second estimated value and the control center value of the remaining capacity value, A control gain setting unit for setting a control gain used in the control calculation of
The estimated value output part which produces | generates the said remaining capacity estimated value by the addition of the said 1st estimated value from the said 1st estimation means and the said remaining capacity correction amount from the said control calculating part is included. Battery remaining capacity estimation system. The control gain setting unit sets the control gain when the first and second estimated values are both larger than the control center value in a region where the first estimated value is larger than the second estimated value. A region where the first estimated value is smaller than the second estimated value while at least one of the first estimated value and the second estimated value is set to be smaller than the control gain when it is equal to or less than the control center value. The control gain when the first and second estimated values are both smaller than the control center value is equal to or greater than at least one of the first and second estimated values is greater than or equal to the control center value. The battery remaining capacity estimation system according to claim 3, wherein the battery remaining capacity estimation system is set smaller than the control gain.   In the region where the first estimated value is larger than the second estimated value, the control gain setting unit is configured such that the first estimated value is larger than the control center value and the second estimated value is the control The first estimated value is set in a region where the first estimated value is smaller than the second estimated value while the control gain when smaller than the center value is set larger than the control gain in other cases. The control gain when the value is smaller than the control center value and the second estimated value is larger than the control center value is set larger than the control gain in other cases. Battery remaining capacity estimation system. The third estimating means includes
A correction amount setting unit that calculates a remaining capacity correction amount by referring to a predetermined map that receives the first estimated value and the second estimated value;
An estimated value output unit that generates the remaining capacity estimated value by adding the first estimated value from the first estimating unit and the remaining capacity correction amount from the correction amount setting unit;
In the predetermined map, a correction ratio defined by a ratio having a deviation of the second estimated value with respect to the first estimated value as a denominator and a map value of the remaining capacity correction amount as a numerator is the first estimated value. 2. The remaining battery according to claim 1, which is set based on a magnitude relationship between the first estimated value and the second estimated value and a magnitude relationship between the first estimated value and the second estimated value and the control center value of the remaining capacity value. Capacity estimation system. The third estimating means calculates a remaining capacity correction amount by referring to a predetermined map having the first estimated value and the second estimated value as inputs.
In the predetermined map, a correction defined by a ratio having a deviation of the second estimated value with respect to the first estimated value as a denominator and a map value difference of the remaining capacity estimated value with respect to the first estimated value as a numerator. The ratio is set based on a magnitude relationship between the first estimated value and the second estimated value and a magnitude relationship between the first and second estimated values and the control center value of the remaining capacity value. The battery remaining capacity estimation system according to claim 1.   In the predetermined map, in the region where the first estimated value is larger than the second estimated value, the correction ratio when both the first and second estimated values are larger than the control center value is A region where the first estimated value is smaller than the second estimated value while at least one of the first and second estimated values is set smaller than the correction ratio in the case where it is equal to or less than the control center value. The correction ratio when both the first and second estimated values are smaller than the control center value is when at least one of the first and second estimated values is greater than or equal to the control center value The remaining capacity estimation system for a battery according to claim 6 or 7, which is set to be smaller than the correction ratio.   In the predetermined map, in a region where the first estimated value is larger than the second estimated value, the first estimated value is larger than the control center value, and the second estimated value is the control center value. The correction ratio in the case where the first estimation value is smaller than the correction ratio in the other case is set to be larger than the correction ratio in the other case, while the first estimation value is smaller than the second estimation value. The correction ratio when the value is smaller than the control center value and the second estimated value is larger than the control center value is set larger than the correction ratio in other cases. The battery remaining capacity estimation system described. A battery remaining capacity estimation method in which charging / discharging is controlled according to a remaining capacity value,
A first estimating step of calculating a first estimated value related to the remaining capacity of the battery from a previous estimated value of the input / output current integrated value of the battery;
A second estimating step for calculating a second estimated value related to the remaining capacity of the battery based on the electromotive voltage of the battery;
Magnitude relationship between the first estimated value and the second estimated value estimated in the first and second estimating steps, and a control center value of the first and second estimated values and the remaining capacity value And a third estimating step of calculating a remaining capacity estimated value by correcting the first estimated value based on a magnitude relationship between the first estimated value and the remaining capacity estimating method.   The battery remaining capacity estimation method according to claim 10, wherein, in the second estimation step, the second estimated value is calculated based on an electromotive voltage of the battery. The third estimating step includes:
Setting a control gain based on a magnitude relationship between the first estimated value and the second estimated value and a magnitude relationship between the first and second estimated values and the control center value of the remaining capacity value; When,
Calculating a remaining capacity correction amount by a control calculation based on a deviation of the second estimated value with respect to the first estimated value using the set control gain;
11. The battery remaining capacity estimating method according to claim 10, further comprising: generating the remaining capacity estimated value by adding the first estimated value estimated in the first estimating step and the remaining capacity correction amount. The third estimating step includes:
Calculating a remaining capacity correction amount by referring to a predetermined map having the first estimated value and the second estimated value as inputs;
Generating the remaining capacity estimated value by adding the first estimated value estimated by the first estimating step and the calculated remaining capacity correction amount;
In the predetermined map, a correction ratio defined by a ratio having a deviation of the second estimated value with respect to the first estimated value as a denominator and a map value of the remaining capacity correction amount as a numerator is the first estimated value. The remaining battery of claim 10, which is set based on a magnitude relationship between the first estimated value and the second estimated value, and a magnitude relationship between the first estimated value and the second estimated value and the control center value of the remaining capacity value. Capacity estimation method. The third estimating step includes:
Generating the remaining capacity estimated value for calculating a remaining capacity correction amount by referring to a predetermined map having the first estimated value and the second estimated value as inputs;
In the predetermined map, a correction defined by a ratio having a deviation of the second estimated value with respect to the first estimated value as a denominator and a map value difference of the remaining capacity estimated value with respect to the first estimated value as a numerator. The ratio is set based on a magnitude relationship between the first estimated value and the second estimated value and a magnitude relationship between the first and second estimated values and the control center value of the remaining capacity value. The battery remaining capacity estimation method according to claim 10.

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