JP2010146792A - Battery controller, and battery control method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a battery controller and a battery control method, capable of controlling properly an operation state of a battery. <P>SOLUTION: A measuring instrument 6 acquires a measured value indicating the operation state of a fuel battery cell 1. A storage portion stores a statistical data indicating a relation between a change direction of the measured data and a change direction of an operation parameter. A computing portion computes the proper operation parameter suitable for making the measured value acquired by the measuring instrument 6 get near to a target value, based on the statistical data stored in the storage portion. A control portion controls the fuel battery cell 1, according to the operation parameter obtained by the computing portion. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a battery control device and a battery control method for controlling an operation state of a battery.

There is known a fuel cell in which a cathode and an anode are opposed to each other with a solid polymer electrolyte membrane interposed therebetween. Gas flow paths for supplying fuel gas are formed in the cathode and the anode, respectively, and electricity is generated by supplying a predetermined gas to the cathode and the anode.
JP 2003-59517 A JP 2007-53013 A JP 2005-108673 A

  In order to exert the original performance of the fuel cell, it is necessary to appropriately control the operating state of the fuel cell by stably forming a three-phase interface inside the fuel cell. For this purpose, it is required to control individual operating parameters such as temperature, pressure, and relative humidity in real time. However, since there is a complicated correlation between the internal state of the fuel cell and the operation parameters, it is extremely difficult to control the internal state of the fuel cell as intended.

  The objective of this invention is providing the battery control apparatus and battery control method which can control the driving | running state of a battery appropriately.

The battery control device of the present invention is a battery control device that controls the operation state of the battery, a measurement value acquisition unit that acquires a measurement value indicating the operation state of the battery, a change direction of the measurement value, and a change direction of the operation parameter. Storage means for storing statistical data indicating the relationship between the measurement value and the measurement data acquired by the measurement value acquisition means, based on the statistical data stored in the storage means, suitable for approaching the target value Computational means for computing operating parameters; and control means for controlling the battery according to the operational parameters obtained by the computing means.
According to this battery control device, since an appropriate operation parameter is calculated in order to bring the measurement value closer to the target value based on the statistical data indicating the relationship between the change direction of the measurement value and the change direction of the operation parameter, the battery It is possible to appropriately control the operating state of the.

  The measured value may be an output voltage of the battery.

  As the operating parameter, any one of temperature, dew point, gas flow rate, pressure, and relative temperature may be used.

The battery control method of the present invention is a battery control method for controlling the operation state of a battery, wherein a step of obtaining a measurement value indicating the operation state of the battery, and a relationship between a change direction of the measurement value and a change direction of the operation parameter is obtained. Based on the statistical data shown, the step of calculating the operation parameter suitable for bringing the measurement value acquired by the step of acquiring the measurement value close to the target value, and the operation parameter obtained by the step of calculating And controlling the battery according to the above.
According to this battery control method, an appropriate operation parameter is calculated to bring the measurement value closer to the target value based on statistical data indicating the relationship between the change direction of the measurement value and the change direction of the operation parameter. It is possible to appropriately control the operating state of the.

  You may provide the step which acquires beforehand the statistical data which show the relation between the change direction of the measured value, and the change direction of an operation parameter by the experiment for the battery.

  According to the battery control device of the present invention, an appropriate operation parameter is calculated in order to bring the measurement value closer to the target value based on statistical data indicating the relationship between the change direction of the measurement value and the change direction of the operation parameter. The battery operating state can be appropriately controlled.

  According to the battery control method of the present invention, an appropriate operation parameter is calculated in order to bring the measurement value closer to the target value based on statistical data indicating the relationship between the change direction of the measurement value and the change direction of the operation parameter. The battery operating state can be appropriately controlled.

  Hereinafter, an embodiment of a battery control device according to the present invention will be described.

  FIG. 1 is a block diagram showing the configuration of the battery control apparatus of this embodiment, and FIG. 2 is a control block diagram showing the configuration of the control system.

  As shown in FIG. 1, the fuel cell 1 is configured by laminating a cathode 11 and an anode 12, each having a gas flow path, through a solid electrolyte membrane 13. The cathode 11 includes a reference electrode 11a formed by dividing a part of the cathode 11, and the anode 12 includes a reference electrode 12a formed by dividing a part of the anode 12. A load 10 is connected between the cathode 11 and the anode 12, but no current is drawn from the reference electrode 11a and the reference electrode 12a.

  As shown in FIG. 1, the gas from the gas supply source 21 is supplied to the cathode 11 via the humidifier 23. A valve 31 is provided in the vicinity of the outlet of the gas supply source 21, a valve 32 is provided in the conduit 25 from the humidifier 23 to the cathode 11, and a valve 33 is provided in the exhaust conduit from the cathode 11.

  On the other hand, the gas from the gas supply source 22 is supplied to the anode 12 via the humidifier 24. A valve 34 is provided in the vicinity of the outlet of the gas supply source 22, a valve 35 is provided in the pipe line 26 from the humidifier 24 to the anode 12, and a valve 36 is provided in the discharge pipe line from the anode 12.

  Also, a heater 41 for heating the pipe 25 is provided in the vicinity of the pipe 25, a heater 42 for heating the pipe 26 is provided in the vicinity of the pipe 26, and a fuel cell is provided in the vicinity of the fuel cell 1. A heater 43 for heating the cell 1 is provided.

  Further, a dew point meter 51 and a thermometer 53 for measuring the humidity and temperature of the gas inside the pipe 25 are provided in the vicinity of the pipe 25, and the gas inside the pipe 26 is located near the pipe 26. A dew point meter 52 and a thermometer 54 for measuring the humidity and temperature are provided. Further, a thermometer 55 for measuring the temperature of the fuel cell 1 is provided in the vicinity of the fuel cell 1.

  As shown in FIG. 1, a measuring device 6 is connected to the cathode 11 and the anode 12.

  As shown in FIG. 2, the measurement value obtained by the measurement device 6 is input to the calculation unit 81. The calculation unit 81 calculates a control value that brings the measurement value from the measurement device 6 close to the target value, and gives the control value to the control unit 7. The storage unit 82 stores a table indicating control indexes necessary for calculation in the calculation unit 81. The table stored in the storage unit 82 will be further described later.

  Further, the measured values from the dew point meter 51, the dew point meter 52, the thermometer 53 and the thermometer 54 are given to the control unit 7, and the humidifier 23, the humidifier 24, the valves 31 to 36 and the heaters 41 to 43 are provided to the control unit 7. Controlled by

  The control unit 7 causes the measurement value from the measurement device 6 to approach the target value via the humidifier 23, the humidifier 24, the valves 31 to 36, and the heaters 41 to 43 in accordance with the control value given from the calculation unit 81. Execute proper control. Specific contents of the control will be described later.

  Next, an example of creating a table indicating a control index will be described.

  First, an experimental design (orthogonal table) is created by listing the factors related to the operation of the fuel cell 1. FIG. 3A shows an example of a three-factor, two-level experimental design. Here, factor A: cell temperature, factor B: dew point, factor C: gas flow rate are selected as operating parameters in the load current I (A). The set values of the factors A, B, and C are values that do not deviate from the range of fine adjustment in order to ensure the linearity of the control index. That is, the value at the two levels is set to a range in which the linearity of the control index is maintained between the two levels.

  Next, an average cell voltage is acquired by repeating the measurement using the fuel cell 1 while switching the test conditions (test conditions 1 to 8). FIG. 3B shows the average cell voltages x1 to x8 obtained by repeating the measurement. If the data components constituting the average cell voltages x1 to x8 are not equally dispersed, and if re-data is acquired or it can be determined that there is a missing value, a known method such as the Fisher-Yates approximation method Substituting values may be calculated and used.

  Next, analysis of variance and F test are performed by a known method. FIG. 3C shows an analysis of variance table. Here, the main factor is a method of not pooling regardless of significance.

  Next, for each test condition (test conditions 1 to 8), a point estimation value is obtained by a known method. FIG. 3D shows the point estimation values (X1 to X8) for each test condition. The calculation formula of the point estimation formula is shown below.

Next, a control index is obtained by subtracting the point estimation values. FIG. 3E shows the control index. Such a control index is obtained by the following calculation.
(1) The amount of change A (1 → 2) when only A is changed from level 1 to level 2 is obtained from X5-X1.
(2) The change amount A (2 → 1) = − A (1 → 2) when only A is changed from level 2 to level 1.
(3) The amount of change B (1 → 2) when only B is changed from level 1 to level 2 is obtained from X3-X1.
(4) The change amount B (2 → 1) = − B (1 → 2) when only B is changed from level 2 to level 1.
(5) The amount of change C (1 → 2) when only C is changed from level 1 to level 2 can be obtained from X2-X1.
(6) Change amount C (2 → 1) = − C (1 → 2) when only C is changed from level 2 to level 1.
(7) The amount of change AB (1 → 2) when A and B are simultaneously changed from level 1 to level 2 is obtained from X7-X1.
(8) The amount of change AB (2 → 1) = − AB (1 → 2) when A and B are simultaneously changed from level 2 to level 1.
(9) The amount of change AC (1 → 2) when A and C are simultaneously changed from level 1 to level 2 can be obtained from X6-X1.
(10) The change amount AC (2 → 1) = − AC (1 → 2) when A and C are simultaneously changed from level 2 to level 1.
(11) The amount of change BC (1 → 2) when B and C are simultaneously changed from level 1 to level 2 is obtained from X4-X1.
(12) The amount of change BC (2 → 1) = − BC (1 → 2) when B and C are simultaneously changed from level 2 to level 1.

  By storing the table group indicating the control index (FIG. 3 (e)) obtained by the procedure as described above in the storage unit 82, it is possible to perform control so that the measurement value from the measurement device 6 approaches the target value. . As the target value, for example, a value corresponding to a state in which an ideal three-phase interface is formed in the fuel cell 1 is selected.

  Next, an operation for controlling the fuel cell 1 that is operating as a power source for supplying current to the load 10 will be described. FIG. 4A is a block diagram illustrating a control procedure in the control unit 7.

  In step S <b> 1 of FIG. 4A, the cell voltage X ′ that is the output voltage of the fuel cell 1 is acquired via the measuring device 6.

Next, in step S2, the cell voltage X ′ and the target value m are compared to determine whether or not the cell voltage X ′ matches the target value m. Here, for example, when Δratio = cell voltage X ′ / target value m−1 and the threshold value (positive number) is “k”, in the calculation unit 81,
−k <Δratio <k
It may be determined whether or not is established. Note that an arbitrary value can be selected as the value of the threshold value k according to a system change including a change of the fuel cell.

  If the determination in step S2 is affirmed, the process returns to step S1, and if the determination is negative, the process proceeds to step S3.

  In step S <b> 3, a necessary table is read from the storage unit 82, an appropriate operation parameter adjustment method is extracted by the calculation unit 81, and this is given to the control unit 7. In accordance with an instruction from the calculation unit 81, the control unit 7 performs control such that the measurement value from the measurement device 6 approaches the target value via the humidifier 23, the humidifier 24, the valves 31 to 36 and the heaters 41 to 43. To do.

  For example, when the target value m = 0.554 (V) and the cell voltage X ′ = 0.530 (V) is obtained, the current value of Δratio is 4.33%. In this case, a pattern that allows Δratio to approach 0 is extracted from the table indicating the control index (FIG. 3E).

  FIG. 4B shows the cell voltage (X ′ + factor effect) after execution and the predicted value of Δratio (Δratio *) when the control index shown in FIG. 3E is executed. As shown in FIG. 4B, if factor A is adjusted in the direction of level 2 → 1 (cell temperature is increased by 3 ° C.), it can be expected that the ratio can be reduced to Δratio = 0.22%. , An instruction to adjust the factor A in the direction of level 2 → 1 is given from the calculation unit 81 to the control unit 7. Note that if there is no pattern in the control index that allows Δratio to approach 0, an instruction to maintain the current operating parameter is given to the control unit 7.

  After the process in step S3, the process returns to step S1.

  By repeating such processing, the control for bringing the cell voltage X ′ closer to the target value m is continuously executed.

  As described above, according to the battery control device of the present embodiment, since the operation parameter is constantly adjusted so that the cell voltage approaches the target value based on the statistical data, the operation parameter is adjusted accurately and accurately. it can.

  In the said embodiment, although illustrated about control of a fuel cell, the kind of battery is not limited to this.

  Further, the factor to be controlled is not limited to the battery output voltage. For example, an overvoltage or an open circuit voltage (OCV) of each electrode may be used. As shown in FIG. 1, in the above embodiment, since the reference electrode 11a and the reference electrode 12a are formed by dividing the cathode and the anode, the potential of the reference electrode 11a or the reference electrode 12a is used as a reference. Thus, it is possible to easily acquire an overvoltage or an open circuit voltage, and to perform control to bring these voltage values close to a target value. A method for acquiring an overvoltage or the like using a reference electrode is disclosed in Japanese Unexamined Patent Application Publication No. 2008-204831.

  In addition, any parameter that can be adjusted during the operation of the battery can be a control target. For example, the load current, the relative humidity, the pressure, and the like may be controlled so as to approach the target value.

  Further, a plurality of factors to be controlled can be provided.

The number of operation parameters to be adjusted may be four or more. For example, by planning experiments such as L ₁₆ , L ₆₄ , L ₂₇ , and L ₈₁ , many operating parameters that affect the battery output voltage and the like can be adjusted, and a reliable internal with little error The state can be controlled. For example, load current, pressure, relative humidity, cell temperature, dew point, humidity, and the like can be used as operation parameters.

  If the scale of the experiment is not a problem, the control index may be obtained from the analysis of multi-way layout with the number of adjustment factors and the number of levels increased.

  In the above embodiment, the point estimation result is used as the control index. However, any value (information) having positive / negative or magnitude can be widely used as the index. For example, an average value or median for each test condition, a level average value for each factor, a factor effect value for each level, or the like can be used.

  The method for setting the target value can be selected as appropriate. For example, the target value may be a population average value for reproducing the internal state of the fuel cell or the like. The target value may be the median. The target value may be the maximum value or the minimum value. Such a method is suitable when priority is given to control suitable for high output operation, low fuel consumption operation, safe operation, or long-time continuous operation, rather than system reproducibility and measurement reliability.

  In addition, as a method of determining the target value, a method of obtaining an operating condition for reducing battery deterioration as much as possible or an operating condition for obtaining a stable output may be used.

  The present invention can also be applied to battery maintenance. Depending on the usage history, the battery deterioration process varies. For this reason, an experiment for acquiring a control index is performed on a battery brought in for maintenance, and the deterioration process is changed by, for example, changing the control index to an operation condition that provides a stable output. The control state commensurate with the battery can be ensured. By changing the control index, it is possible to minimize deterioration due to battery operation.

  Further, the present invention is applicable not only to the control of an operating battery, but also to control for appropriately maintaining the operating state of the battery when measuring the battery.

  The scope of application of the present invention is not limited to the above embodiment. The present invention can be widely applied to a battery control device and a battery control method for controlling the operation state of a battery.

The block diagram which shows the structure of the battery control apparatus of one Embodiment. The control block diagram which shows the structure of a control system. It is a figure which shows the acquisition method of statistical data, (a) is a figure which shows the example of the experiment plan of 3 factor 2 level, (b) is a figure which shows the value of the average cell voltage obtained by repeating a measurement, (C) is a figure which shows an analysis of variance table, (d) is a figure which shows the point estimated value for every test condition, (e) is a figure which shows a control parameter | index. It is a figure which shows the control method in a control part, (a) is a block diagram which shows the control procedure in a control part, (b) is a figure which shows the cell voltage after control index execution, and the predicted value of (DELTA) ratio.

Explanation of symbols

1 Fuel cell (battery)
6 Measuring device (Measurement value acquisition means)
7 Control unit (control means)
81 Calculation unit (calculation means)
82 Storage unit (storage means)

Claims (5)

In the battery control device for controlling the operating state of the battery,
A measurement value acquisition means for acquiring a measurement value indicating the operating state of the battery;
Storage means for storing statistical data indicating a relationship between a change direction of the measurement value and a change direction of the operation parameter;
Based on the statistical data stored in the storage means, calculation means for calculating the operation parameter suitable for bringing the measurement value acquired by the measurement value acquisition means close to a target value;
Control means for controlling the battery according to the operating parameters obtained by the computing means;
A battery control device comprising: The battery control apparatus according to claim 1, wherein the measured value is an output voltage of the battery. The battery control device according to claim 1 or 2, wherein any one of temperature, dew point, gas flow rate, pressure, and relative temperature is used as the operation parameter. In the battery control method for controlling the operating state of the battery,
Obtaining a measured value indicating the operating state of the battery;
Based on statistical data indicating the relationship between the change direction of the measurement value and the change direction of the operation parameter, the operation parameter appropriate for bringing the measurement value acquired in the step of acquiring the measurement value close to the target value is set. A step of calculating;
Controlling the battery according to the operating parameters obtained by the calculating step;
A battery control method comprising: 5. The battery control according to claim 4, further comprising a step of acquiring in advance the statistical data indicating a relationship between a change direction of the measurement value and a change direction of an operation parameter by an experiment on the battery. Method.

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