WO2019138805A1

WO2019138805A1 - Vehicle control device

Info

Publication number: WO2019138805A1
Application number: PCT/JP2018/046617
Authority: WO
Inventors: 雄介平光; 佳紀水下; 力竹井
Original assignee: 三菱自動車工業株式会社
Priority date: 2018-01-12
Filing date: 2018-12-18
Publication date: 2019-07-18

Abstract

A control device (2) for a vehicle (1) equipped with a rechargeable secondary battery (3) and a power supply/reception device (5, 9) capable of at least either supplying power to or receiving power from the secondary battery (3) is provided with: an estimation unit (2A) for estimating the state of charge of the secondary battery (3); a parking determination unit (2B) for determining whether the vehicle (1) is in a parking state or not; and a control unit (2D) for, when a predetermined charge/discharge condition is satisfied, activating the power supply/reception device (5, 9) to perform additional charging or additional discharging on the secondary battery (3). The charge/discharge condition includes that the parking determination unit (2B) has determined that the vehicle (1) is in the parking state and includes that the state of charge estimated by the estimation unit (2A) is within a control range corresponding to a predetermined deterioration progressing range except a fully charged range and a null-charged range.

Description

Vehicle control device

The present invention relates to a control device of a vehicle provided with a chargeable / dischargeable secondary battery.

In recent years, electric vehicles and hybrid vehicles equipped with a motor as a drive source have been put into practical use in consideration of environmental problems. In such an electric vehicle, a secondary battery that supplies electric power to a motor to generate a driving force is mounted. The secondary battery is configured to be capable of charging generated power by a power generation device (generator operated by an engine, a fuel cell, etc.) mounted on a vehicle and externally charging. In addition, when traveling downhill or during braking, etc., the motor is brought to rotate, and it is possible to charge electric power regenerated and generated.

Since the battery performance (charge capacity) of the on-board secondary battery greatly affects the cruising distance of the electric vehicle, it is required to be maintained in a high state. It is known that secondary batteries deteriorate due to overdischarge or overcharge, and the battery performance is degraded. For this reason, a technology has been proposed that estimates and detects the charge state (charge rate) of the secondary battery and controls the charge state of the secondary battery so as not to be overdischarged or overcharged (see, for example, Patent Document 1) .

JP, 2001-268707, A

However, depending on the material constituting the secondary battery, specific deterioration may progress even if the secondary battery is in the overdischarged or overcharged state, and the battery performance of the secondary battery may be degraded. It became clear. That is, when the state in which the charging rate of the secondary battery is in the range in which the deterioration is likely to be stored, the deterioration progresses even if the secondary battery is not used, which leads to the deterioration of the battery performance. It causes a decrease in the cruising distance.

The control device for a vehicle according to the present invention has been devised in view of such findings, and has an object to suppress deterioration of a chargeable / dischargeable secondary battery. The present invention is not limited to this object, and it is an operation and effect derived from each configuration shown in the “embodiments to be described later”, and it is also possible to exert an operation and effect that can not be obtained by the prior art. It can be positioned as a goal.

(1) The control device for a vehicle disclosed herein comprises: a chargeable / dischargeable secondary battery; and a power transfer device capable of at least one of power supply to the secondary battery and power reception from the secondary battery. In the control device of the vehicle, the estimation unit that estimates the charging rate of the secondary battery, the parking determination unit that determines whether the vehicle is in the parking state, and a predetermined charge and discharge condition are satisfied. And a controller configured to operate the power transfer device to additionally charge or discharge the secondary battery. For the charge / discharge condition, it is determined that the vehicle is in the parked state by the parking determination unit, and the charge rate estimated by the estimation unit is a predetermined value excluding the full charge range and the idle charge range It is included in the control range corresponding to the degradation progress range of

(2) The control unit performs the additional discharge when the charge rate is less than a predetermined charge / discharge determination threshold within the deterioration progress range when the charge / discharge condition is satisfied, and the charge rate is charged Preferably, the additional charging is performed when the discharge determination threshold value or more.

(3) The power exchange device preferably includes a chargeable / dischargeable auxiliary battery mounted on the vehicle. In this case, the control unit preferably operates the auxiliary battery to perform the additional discharge while charging the auxiliary battery with the power of the secondary battery when the additional discharge is performed.

(4) The power transfer device preferably includes a power generation device capable of charging the secondary battery. In this case, the control unit determines whether the additional charging by the auxiliary battery is possible when the additional charging is performed, and the auxiliary battery when the additional charging by the auxiliary battery is possible. Is preferably operated to perform the additional charging, and when the additional charging by the auxiliary battery can not be performed, the power generation device is operated to perform the additional charging.

(5) The power generation device is preferably a fuel cell.
(6) Preferably, the power transfer device includes a fuel cell mounted on the vehicle. In this case, the control unit preferably operates the fuel cell when the additional charge is performed.

(7) The control device preferably includes a state determination unit that determines the deterioration state of the fuel cell. In this case, the control unit operates the fuel cell to perform the additional charge, and when the state determination unit determines that the fuel cell is in the deteriorated state, the performance of the fuel cell Preferably, the fuel cell is operated to perform the additional charge in a recovery operation mode for recovering the

(8) In the case where the control unit operates the fuel cell to perform the additional charge, and the state determination unit determines that the fuel cell is not in the deteriorated state, the fuel cell has the highest efficiency. It is preferable to operate in the operation mode to carry out the additional charge.
(9) When the fuel cell is operated to perform the additional charge by operating the fuel cell, the state determination unit operates the fuel cell based on an actual voltage value when the fuel cell is operated to a desired voltage. It is preferable to determine whether or not the vehicle is in a deteriorated state.

(10) Preferably, in the recovery operation mode, the control unit controls the operating state of the fuel cell such that the voltage of the fuel cell repeatedly rises and falls.
(11) In the recovery operation mode, the control unit may lower the voltage of the fuel cell to a predetermined lower limit and lower the lower limit as the number of repetitions of increase and decrease of the voltage increases. preferable.

(12) It is preferable that the determination that the parking determination unit determines that the vehicle is in the parked state includes that the main power supply of the vehicle is in the off state.
(13) It is preferable that the determination condition that the parking determination unit determines that the vehicle is in the parked state includes that an occupant does not board the vehicle.

(14) Preferably, the parking determination unit determines that the vehicle is in the parking state when the determination condition is satisfied continuously for a predetermined time or more.
(15) The control device preferably includes time setting means for setting the predetermined time.

According to the disclosed vehicle control device, when the vehicle is in the parked state and the charging rate of the secondary battery is within the predetermined control range corresponding to the predetermined deterioration progress range, the power transfer device is By activating the secondary battery for additional charge or additional discharge, it is possible to suppress the deterioration of the secondary battery and, consequently, to prevent the reduction of the cruising distance.

1 is a schematic view of a vehicle to which a control device according to a first embodiment is applied. It is a flowchart for demonstrating an example of the charging / discharging control implemented by the control apparatus of FIG. It is the schematic of the vehicle by which the control apparatus which concerns on 2nd Embodiment was applied. FIG. 4 is a schematic view of a fuel cell mounted on the vehicle of FIG. 3; FIG. 6 is a chart illustrating a change in voltage value of the fuel cell when the fuel cell is activated and additional charging is performed while the vehicle in FIG. 3 is stopped, and a change in the charging rate of the secondary cell accordingly. It is a subflowchart of FIG. 2 for demonstrating an example of the charging / discharging control implemented by the control apparatus of FIG.

A control device of a vehicle will be described with reference to the drawings. Note that the embodiments described below are merely illustrative, and there is no intention to exclude the application of various modifications and techniques that are not specified in the following embodiments. Each structure of this embodiment can be variously modified and implemented in the range which does not deviate from those meaning. Also, they can be selected as needed or can be combined as appropriate.

First Embodiment
[1. Device configuration]

A vehicle 1 to which the control device 2 of the present embodiment is applied is shown in FIG. The vehicle 1 is a hybrid vehicle (car) equipped with a motor 4 and an engine 8 as drive sources, and a secondary battery 3 as a traveling battery for supplying electric power to the motor 4. Further, the vehicle 1 mounts a generator 5 operated by the power of the engine 8 as a power generation device.

The motor 4 and the generator 5 are a motor generator (motor generator) which has a function as an electric motor and a function as a generator. An inverter 6 (INV) is interposed on an electric circuit connecting each of the motor 4 and the generator 5 to the secondary battery 3. The inverter 6 is a power converter that converts DC power and AC power.

The secondary battery 3 is a chargeable / dischargeable power storage device, and is, for example, a lithium ion secondary battery, a lithium ion polymer secondary battery, or the like. The secondary battery 3 is configured to be chargeable by the power supplied from the power transfer device mounted on the vehicle 1 and configured to be dischargeable by supplying power to the power transfer device. Further, the secondary battery 3 is configured to be chargeable by the power supplied from the external power supply.

The above-described power transfer device is a device capable of at least one of power supply to the secondary battery 3 and power reception from the secondary battery 3. The vehicle 1 of the present embodiment is provided with the above-described generator 5 and a chargeable / dischargeable auxiliary battery 9 as a power transfer device. The auxiliary battery 9 is a storage device capable of supplying power to the secondary battery 3 and receiving power from the secondary battery 3, and is, for example, a lithium ion secondary battery, a lithium ion polymer secondary battery, or the like.

On the electric circuit connecting the auxiliary battery 9 and the secondary battery 3, a changeover switch 9s for switching the connection / disconnection state of this circuit is interposed. When the changeover switch 9s is in the closed state (connected state), power can be exchanged between the auxiliary battery 9 and the secondary battery 3. The changeover switch 9 s switches the connection state and the interruption state of the auxiliary battery 9 and the secondary battery 3 according to the connection signal or the interruption signal from the control device 2.

The vehicle 1 is provided with sensors 11 to 14 for detecting or setting the state of the vehicle 1. The vehicle speed sensor 11 detects the vehicle speed V of the vehicle 1, and the shift position sensor 13 detects a shift position. The ignition switch 12 sets the on / off state of the main power supply (ignition key) of the vehicle 1. The load sensor 14 is a strain gauge or the like attached to a seat (not shown) provided in the vehicle 1 and detects the state of load on the seat. The vehicle 1 is provided with a control device 2 (Electronic Control Unit, ECU) that performs integrated control of various devices mounted on the vehicle 1, and information detected by the sensors 11 to 14 is transmitted to the control device 2 .

Further, the vehicle 1 of the present embodiment is provided with a time setting unit 10 that allows the user to arbitrarily set a predetermined time described later. The time setting unit 10 is, for example, a touch panel of a navigation system, and is a device to which information is input by a manual operation by a user. The time setting means 10 is one of the elements of the control device 2, and the predetermined time set by the time setting means 10 is transmitted to a parking judgment unit 2B described later.

[2. Control outline]

The control device 2 according to the present embodiment performs charge / discharge control that operates the power transfer device to additionally charge or additionally discharge the secondary battery 3 when a predetermined charge / discharge condition is satisfied while the vehicle 1 is stopped. . Whether or not the vehicle 1 is stopped is determined based on whether or not the vehicle speed V detected by the vehicle speed sensor 11 is zero.

It has become clear that, depending on the material of the secondary battery 3, specific deterioration proceeds even if it is not in the overdischarged state or the overcharged state. Specifically, it has been found that when the secondary battery 3 is stored in a state in which the charging rate of the secondary battery 3 is in a range in which the deterioration tends to progress, the deterioration proceeds in the meantime. The charge / discharge control of the present embodiment is implemented to prevent such deterioration.

In the present embodiment, when all of the following conditions 1 to 3 are satisfied, it is determined that the above-mentioned charge and discharge conditions are satisfied. That is, charge / discharge control is performed when all of the conditions 1 to 3 are satisfied. In addition, if at least one of the conditions 1 to 3 is not satisfied during the charge / discharge control, the charge / discharge control is ended.
== charge / discharge condition ==
Condition 1: The state of charge SOC of the secondary battery 3 is within a control range corresponding to a predetermined degradation progress range (see FIG. 5)
Condition 2: Vehicle 1 is in a parked condition Condition 3: External charging is not performed

Condition 3 is a condition provided in view of the fact that if external charging is in progress, even if condition 1 is satisfied when condition 2 is satisfied, then condition 1 should not be satisfied eventually. When the charging gun is inserted into the charging port, communication is started between the vehicle 1 and the external charging device, so the condition 3 is determined based on this information.

That is, the charge / discharge control of the present embodiment is performed when the secondary battery 3 is not externally charged even after a while after the vehicle 1 has stopped and the deterioration of the secondary battery 3 is likely to progress. Be done. Note that it is sufficient that at least both of the condition 1 and the condition 2 are included in the implementation condition of the charge and discharge control, the condition 3 may be omitted.

The "deterioration progress range" of condition 1 means the range of the charging rate in which the above-mentioned specific degradation progresses. The deterioration progress range is a charging rate range when the secondary battery 3 is almost fully charged (hereinafter referred to as “full charging range”) and a charging rate range when the secondary battery 3 is almost empty ( Hereinafter, it exists in the range of the charge rate except the "empty charge range." The deterioration progress range is determined by the material of the secondary battery 3. In addition to the material of the secondary battery 3, the range of progress of deterioration also changes depending on, for example, the environmental conditions (temperature, humidity, etc.) in which the secondary battery 3 is stored. For this reason, the deterioration progress range is not limited to a fixed value, and may be a variable value that changes according to the environmental conditions in which the secondary battery 3 is stored.

Moreover, the "control range" of condition 1 means the range of the charging rate including the deterioration progress range. Specifically, the "control range" is a range of the charging rate wider than the degradation progress range, and the lower limit value thereof is set to a value lower than the lower limit value of the degradation progress range, and the upper limit value thereof is the degradation progress range It is set to a value larger than the upper limit value of.

In the "parked state" of condition 2, after the vehicle 1 is stopped, the state in which the occupant is absent continues for a certain time or more. That is, even after stopping the vehicle 1, for example, the temporary stopping state where the stopping time is short, such as when waiting for a signal, waiting for crossing or getting on or off a passenger or loading / unloading luggage into the vehicle 1, is parked. Not included

In the present embodiment, when all of the following conditions 4 to 8 are satisfied, it is determined that the vehicle 1 is in the parking state. If at least one of the conditions 4 to 7 is not satisfied after it is determined that the vehicle is in the parking state, it is determined that the vehicle is not in the parking state.
== Parking condition ==
Condition 4: Vehicle speed V is 0 Condition 5: Main power supply of vehicle 1 is in OFF state (IG-OFF) Condition 6: Shift position is P Condition 7: Passengers board the vehicle 1 Condition 8: A predetermined time elapses after all the conditions 4 to 7 are satisfied.

The "predetermined time" of the condition 8 is set to a time longer than the necessary time assumed when waiting for a signal, waiting for crossing or crossing, getting on or off passengers or loading / unloading of luggage into / from the vehicle after stopping the vehicle 1. . In particular, in the present embodiment, the predetermined time is set to be longer than the time required for the external charge of the secondary battery 3 to start after the occupant of the vehicle 1 gets off. The predetermined time may be a fixed value, or may be a variable that can be arbitrarily set by the user. In the present embodiment, the predetermined time is set by the time setting unit 10 as a variable value which can be arbitrarily set by the user.

[3. Control configuration]
As shown in FIG. 1, the control unit 2 is provided with an estimation unit 2A, a parking determination unit 2B, and a control unit 2D as elements for performing the above-described charge and discharge control. Each of these elements may be realized by an electronic circuit (hardware), may be programmed as software, or some of these functions may be provided as hardware and the other as software. It may be one. Further, the control device 2 is provided with a timer for measuring an elapsed time from the time when all the above conditions 4 to 7 are satisfied.

3-1. Estimator]

The estimation unit 2A estimates the charging rate SOC of the secondary battery 3. The charging rate SOC is calculated (estimated) based on, for example, a measured value or an estimated value of the open circuit voltage of the secondary battery 3. Alternatively, it is also possible to calculate (estimate) the charging rate SOC by integrating the charge / discharge current of the secondary battery 3 and tracking the increase / decrease change of the remaining power. In the present embodiment, the ratio of the remaining power to the maximum charge capacity of the secondary battery 3 is expressed as a percentage, which is estimated as the charging rate SOC. The charging rate SOC estimated here is transmitted to the control unit 2D.

[3-2. Parking judgment section]

The parking determination unit 2B determines whether the vehicle 1 is in a parked state. The parking determination unit 2B acquires the information from each of the sensors 11 to 14 and the information set by the time setting unit 10, and determines whether or not the parking condition is satisfied based on the acquired information. Thus, it is determined whether the vehicle 1 is in a parked state.

Specifically, parking determination unit 2B determines whether vehicle speed V is 0 or not based on vehicle speed V detected by vehicle speed sensor 11 (condition 4), and turns on / off the main power source set by ignition switch 12 Based on the state, it is determined whether or not IG-OFF (condition 5). The parking determination unit 2B determines whether the shift position is P based on the shift position detected by the shift position sensor 13 (condition 6), and the presence or absence of a load on the seat detected by the load sensor 14 It is determined whether the passenger is on the vehicle 1 based on (Condition 7). In the present embodiment, when the vehicle 1 is at a stop, that is, when the vehicle speed V is 0, it is determined whether the charge / discharge condition is satisfied, so the condition 4 always holds.

Furthermore, the parking judgment unit 2B starts measurement by the timer when all of the conditions 4 to 7 are satisfied. The parking determination unit 2B determines whether the condition 8 is met based on whether the timer count value is equal to or more than the predetermined time set by the time setting unit 10. The timer resets the value when at least one of the conditions 4 to 7 is not satisfied.

The parking determination unit 2B determines that the vehicle 1 is in the parking state when all of the conditions 4 to 8 are satisfied. Here, in view of the fact that all of the conditions 4 to 7 are satisfied, which is one of the conditions (preconditions) of the condition 8 being satisfied, the parking judgment unit 2B determines that the condition 8 is satisfied. In other words, it can be determined that the vehicle 1 is in the parked state. On the other hand, the parking judgment unit 2B judges that the vehicle 1 is not in the parking state when at least one of the conditions 4 to 8 is not satisfied.

[3-3. Control unit]

The control unit 2D operates the power transfer device to additionally charge or discharge the secondary battery 3 when the charge / discharge conditions are satisfied while the vehicle 1 is stopped. That is, when the vehicle 1 stops, the control unit 2D determines the success or failure of the charge / discharge condition, and carries out charge / discharge control according to the determination result.

Control unit 2D determines the above condition 1 using the charging rate SOC estimated by estimation unit 2A. Further, the above-mentioned condition 2 is determined using the determination result acquired from the parking determination unit 2B, and the above-mentioned condition 3 is determined based on the communication information with the external charging device.

When all the conditions 1 to 3 are satisfied, the control unit 2D determines that the above-mentioned charge / discharge condition is satisfied. On the other hand, when at least one of the conditions 1 to 3 described above is not satisfied, the power transfer device is stopped and the charge and discharge control is ended.

When performing charge / discharge control, the control unit 2D of the present embodiment selects whether to perform additional charging or additional discharging based on the charging rate SOC of the secondary battery 3 estimated by the estimating unit 2A. Specifically, when charge ratio SOC estimated by estimation unit 2A is less than predetermined charge / discharge determination threshold SOCth (SOC <SOCth), control unit 2D selects to perform additional discharge, and estimation unit 2A When the charging rate SOC estimated in the above is greater than or equal to a predetermined charge / discharge determination threshold SOCth (SOCthSOCth), the additional charge is selected.

Here, the charge / discharge determination threshold SOCth is a predetermined value within the above-described deterioration progress range. The control unit 2D selects the additional charge or the additional discharge based on the charge ratio SOC of the secondary battery 3 and the charge / discharge determination threshold SOCth to achieve efficient charge / discharge control. In the present embodiment, the charge / discharge determination threshold SOCth is set to the median value of the deterioration progress range, but the charge / discharge determination threshold SOCth is not limited to this value. For example, when additional charging is preferentially performed at the time of charge / discharge control, the charge / discharge determination threshold SOCth may be set to a value lower than the median value of the deterioration progress range. Conversely, when the additional discharge is preferentially performed at the time of charge / discharge control, the charge / discharge determination threshold SOCth may be set to a value higher than the central value of the deterioration progress range.

The control unit 2D operates the auxiliary battery 9 to perform the additional discharge while charging the auxiliary battery 9 with the power of the secondary battery 3 when performing the additional discharge. More specifically, when performing additional discharge, the control unit 2D controls the changeover switch 9s to be in the connection state, electrically connects the auxiliary battery 9 and the secondary battery 3, and performs secondary operation. The power stored in the battery 3 is transmitted to the auxiliary battery 9 to perform additional discharge.

On the other hand, control part 2D judges whether additional charge by auxiliary battery 9 is possible, when performing additional charge, and when additional charge by auxiliary battery is possible, operates auxiliary battery 9 The additional charge is performed, and when the additional charge by the auxiliary battery 9 can not be performed, the generator 5 which is a power generation device is operated to perform the additional charge.

The determination as to whether or not additional charging by the auxiliary battery 9 is possible includes calculating the amount of electric power (charging amount) stored in the auxiliary battery 9 and the amount of electric power required until charge / discharge control is completed (necessary charge The amount is calculated, and the determination is made by comparing the charge amount with the required charge amount. The charge amount of the auxiliary battery 9 is calculated based on, for example, a measured value or an estimated value of the open circuit voltage of the auxiliary battery 9. The required charge amount is calculated from the difference between the state of charge SOC of the secondary battery 3 and the upper limit value of the control range.

When the charge amount of the auxiliary battery 9 is larger than the required charge amount, the control unit 2D determines that the additional charge by the auxiliary battery 9 is possible, operates the auxiliary battery 9 and additionally charges the secondary battery 3 Do. That is, the switch 9 s is controlled to be in the connection state, the auxiliary battery 9 and the secondary battery 3 are electrically connected, and the secondary battery 3 is charged by the power stored in the auxiliary battery 9.

On the other hand, when the charging amount of the auxiliary battery 9 is equal to or less than the necessary charging amount, the control unit 2D determines that the additional charging by the auxiliary battery 9 can not be performed and operates the generator 5 to additionally charge the secondary battery 3 . More specifically, the control unit 2D operates the generator 5 by driving the engine 8, and charges the secondary battery 3 with the regenerative power of the generator 5.

[4. flowchart]

FIG. 2 is an example of a flowchart for explaining the contents of the above-described charge and discharge control. This flowchart is started in the control device 2 when the vehicle 1 is stopped and the external charging is not performed and the conditions 4 to 7 of the above-mentioned parking conditions are satisfied, and the flowchart is started while the vehicle 1 is stopped. It is implemented in a predetermined operation cycle. When external charging is started or when the vehicle 1 is not parked, the flowchart ends at that time. That is, charge and discharge control is completed.

In step S1, it is determined whether the predetermined time has elapsed. If the predetermined time has not elapsed, the flow is returned. In step S1, if the predetermined time has elapsed, the process proceeds to step S2, and the charging rate SOC of the secondary battery 3 is acquired. In step S3, it is determined whether the acquired charging rate SOC is within the control range. If it is determined that the state of charge SOC of the secondary battery 3 is within the control range, the process proceeds to step S4. On the other hand, when it is determined in step S3 that the state of charge SOC of the secondary battery 3 is not within the control range, it is not necessary to carry out additional charging or discharging, so this flow is returned.

In step S4, it is determined whether the charging rate SOC of the secondary battery 3 is equal to or higher than the charge / discharge determination threshold SOCth. In step S4, when the charging rate SOC of the secondary battery 3 is equal to or higher than the charge / discharge determination threshold SOCth (SOC SOC SOCth), the process proceeds to step S5.

On the other hand, if the charging rate SCO of the secondary battery 3 is less than the charge / discharge determination threshold SOCth in step S4 (SOC <SOCth), the process proceeds to step S12, the auxiliary battery 9 is operated, and the secondary battery 3 is The battery is additionally discharged, and in the subsequent step S13, the charging rate SOC of the secondary battery 3 is obtained. Furthermore, in step S14, it is determined whether the acquired charging rate SOC is within the control range. If it is determined in step S14 that the state of charge SOC of the secondary battery 3 is within the control range, the process returns to step S12, the operation of the auxiliary battery 9 is continued, and the secondary battery 3 is additionally discharged. Then, if it is determined in step S14 that the charging rate SOC of the secondary battery 3 is not within the control range, the secondary battery 3 is out of the charging rate range where deterioration is likely to progress, so the operation of the auxiliary battery 9 is stopped. , Return this flow.

In step S5, it is determined whether additional charging can be performed by the auxiliary battery 9. Specifically, the charge amount of the auxiliary battery 9 and the required charge amount are calculated, and it is determined whether the charge amount of the auxiliary battery 9 is larger than the required charge amount, whereby the auxiliary battery 9 performs additional charge. It is determined whether or not it is possible.

In step S5, additional charging can be performed by the auxiliary battery 9, that is, when the charging amount of the auxiliary battery 9 exceeds the necessary charging amount, the process proceeds to step S6, the auxiliary battery 9 is operated and the secondary battery 3 is additionally charged. In the subsequent step S7, the charging rate SOC of the secondary battery 3 is obtained. Furthermore, in step S8, it is determined whether the acquired charging rate SOC is within the control range. If it is determined in step S8 that the state of charge SOC of the secondary battery 3 is within the control range, the process returns to step S6, the operation of the auxiliary battery 9 is continued, and the secondary battery 3 is additionally charged. When it is determined in step S8 that the state of charge SOC of the secondary battery 3 is not within the control range, this flow is returned.

On the other hand, if the additional charge can not be performed by the auxiliary battery 9 in step S5, that is, the charge amount of the auxiliary battery 9 is equal to or less than the required charge amount, the process proceeds to step S9 to operate the generator 5 and add the secondary battery 3 After being charged, in the subsequent step S10, the charging rate SOC of the secondary battery 3 is obtained. Furthermore, in step S11, it is determined whether the acquired charging rate SOC is within the control range. If it is determined in step S11 that the state of charge SOC of the secondary battery 3 is within the control range, the process returns to step S9, the operation of the generator 5 is continued, and the secondary battery 3 is additionally charged. When it is determined in step S11 that the state of charge SOC of the secondary battery 3 is not within the control range, this flow is returned.

After the flow is returned, that is, after the charge / discharge control is performed and the charge ratio SOC of the secondary battery 3 is out of the control range, the charge ratio of the secondary battery 3 is again caused by the natural discharge of the secondary battery 3 If the SOC falls within the control range (step S3), additional discharge or additional charge is performed again.

[5. Action, effect]

(1) In the control device 2 of the vehicle 1 described above, the vehicle 1 is in a parked state, and the state of charge SOC of the secondary battery 3 corresponds to a predetermined deterioration progress range excluding the full charge range and the idle charge range. When the charge / discharge condition including the fact that it is within the above control range is satisfied, the power transfer device operates and the secondary battery 3 is additionally charged or additionally discharged. Therefore, the deterioration of the secondary battery 3 can be suppressed, and the decrease of the cruising distance of the vehicle 1 can be prevented.

In addition, the control device 2 described above has one of the charge and discharge conditions that the state of charge SOC of the secondary battery 3 is within a control range wider than the degradation progress range. For this reason, the charging rate SOC of the secondary battery 3 after the end of charge / discharge control can be more reliably removed from the deterioration progress range. Furthermore, since the above-mentioned charge / discharge control can be performed even when the charging rate SOC of the secondary battery 3 is out of the deterioration progress range but is near the deterioration progress range, the secondary battery 3 can be more reliably Deterioration can be suppressed.

(2) When the charge / discharge condition is satisfied, the control device 2 additionally discharges when the charge ratio SOC is less than the charge / discharge determination threshold SOCth, and when the charge ratio SOC is equal to or greater than the charge / discharge determination threshold SOCth Add to Thus, the charging rate SOC is less than the charging / discharging determination threshold SOCth, that is, additional charging is performed when the control range is relatively close to the lower limit value, and the charging rate SOC is higher than the charging / discharging determination threshold SOCth, ie By carrying out the additional charge when the upper limit value of the control range is relatively close, the charge / discharge control can be made more efficient.

(3) The above-described vehicle 1 is provided with the auxiliary battery 9 as a power transfer device, and when the additional discharge is performed, the auxiliary battery 9 is operated to charge the auxiliary battery 9 with the power of the secondary battery 3 to add Discharge. Therefore, the secondary battery 3 can be additionally discharged without wasting the power stored in the secondary battery 3.

(4) The vehicle 1 described above is provided with a power generation device (generator 5) capable of charging the secondary battery 3 as a power transfer device. Further, when the auxiliary battery 9 can not perform additional charging, the control device 2 operates the generator 5 to perform additional charging. Therefore, when additional charging can be performed by the auxiliary battery 9, additional charging can be performed without consuming the fuel (such as gasoline) stored in the vehicle 1, while when additional charging can not be performed by the auxiliary battery 9, By operating the generator 5 to perform additional charging, the charging rate SOC of the secondary battery 3 can be reliably made out of the control range.

(5) The determination condition that the parking determination unit 2B described above determines that the vehicle 1 is in the parking state includes that the main power supply of the vehicle 1 is in the off state. For this reason, it is possible to make it easy to exclude from the parking state the temporary stop state having a short stop time as described above.

(6) Further, the determination condition that the parking determination unit 2B described above determines that the vehicle 1 is in the parked state includes that the passenger is not on the vehicle 1. For this reason, it is possible to more reliably exclude from the parking state the temporary stopping state where the stopping time is short as described above.

(7) The parking determination unit 2B determines that the vehicle 1 is in the parking state when the condition (precondition) for determining the parking state is satisfied for a predetermined time or more. As described above, even if the precondition is satisfied, it is not determined that the vehicle is in the parking state until the predetermined time elapses, which makes it difficult for the charge and discharge control to be performed until the external charge is performed. That is, implementation of unnecessary charge / discharge control can be suppressed. As a result, the consumption of the power and fuel stored in the vehicle 1 can be suppressed.

(8) The above-described control device 2 includes time setting means 10 for setting a predetermined time. Therefore, the user can set the timing at which the charge and discharge control is performed. For this reason, it can suppress that charge / discharge control is implemented contrary to a user's will, and it becomes possible to suppress the consumption of the electric power and fuel which were stored by the vehicle 1. FIG.

Second Embodiment
A second embodiment of the present invention will be described with reference to FIGS. 3 to 6. The present embodiment differs from the first embodiment in the power transfer device provided in the vehicle 1 '. In addition, the addition of the state determination unit 2C to the control device 2 'causes part of the functions of the control unit 2D' to be different. The other components are the same as those of the first embodiment, and therefore, will be described with the same reference numerals as in the first embodiment.

[1. Device configuration]
[1-1. overall structure]

A vehicle 1 'to which the control device 2' of the present embodiment is applied is shown in FIG. This vehicle 1 'is a fuel cell vehicle mounted with a motor 4 as a drive source, a secondary battery 3 as a traveling battery for supplying electric power to the motor 4, and a fuel cell 5' as a power generation device. The motor 4 is a motor generator (motor generator) which has a function as an electric motor and a function as a generator. An inverter 6 (INV) is interposed on the electric circuit connecting the secondary battery 3 and the motor 4.

The vehicle 1 'of this embodiment is provided with the above-described fuel cell 5' and an auxiliary battery 9 as a power transfer device. In the vehicle 1 ′, a changeover switch 9 s is interposed on an electric circuit connecting the auxiliary battery 9 and the secondary battery 3. The auxiliary battery 9 and the changeover switch 9s are the same as those in the first embodiment, and thus the description thereof is omitted.

The secondary battery 3 is a storage device which can be charged by the regenerative power generated by the vehicle 1 ', the external power supply, and the power supplied from the fuel cell 5', for example, a lithium ion secondary battery or a lithium ion polymer secondary battery is there. A converter 7 (DC-DC converter) for voltage conversion is interposed on the electric circuit connecting the secondary battery 3 and the fuel cell 5 '.

The fuel cell 5 'is a power generation apparatus for extracting electric power by utilizing an electrical reaction between hydrogen in the fuel and oxygen in the air, and is, for example, a polymer electrolyte fuel cell or a phosphoric acid fuel cell. The electric power (electric power) generated by the fuel cell 5 ′ is mainly used to charge the secondary battery 3. When the load of the motor 4 is large enough to exceed the power supply capacity of the secondary battery 3, the electric power of the fuel cell 5 ′ is directly supplied to the motor 4. In the present embodiment, the fuel cell 5 'is described as being a polymer electrolyte fuel cell (PEFC).

The inverter 6 is a power converter that converts DC power and AC power. The converter 7 boosts the DC power generated by the fuel cell 5 'and supplies it to the secondary battery 3 and the motor 4 side. Further, the vehicle 1 'is provided with a vehicle speed sensor 11 for detecting a vehicle speed, and a control device 2' (Electronic Control Unit, ECU) for integrally controlling various devices mounted on the vehicle 1 '. The information detected by the vehicle speed sensor 11 is transmitted to the control device 2 '.

In addition to the above-described vehicle speed sensor 11, the vehicle 1 'is provided with sensors 12-14 for detecting the state of the vehicle 1'. Further, the vehicle 1 'is provided with time setting means 10 for setting a predetermined time which is a parameter necessary for determining the parking state. The time setting means 10 is one of the elements of the control device 2 ', as in the first embodiment. The sensors 12 to 14 and the time setting unit 10 are the same as in the first embodiment, and thus the description thereof is omitted.

[1-2. Fuel Cell Configuration]

FIG. 4 is a schematic view showing an example of a fuel cell 5 'mounted on the vehicle 1' of FIG. As shown in FIG. 4, the fuel cell 5 'of this embodiment includes a fuel cell stack 50 which is a power generation element, a hydrogen supply device 20 and an air supply device 30 for supplying a gas to the fuel cell stack 50, A cooling device 40 for cooling the fuel cell stack 50 is provided. The electric power generated by the fuel cell 5 ′ (fuel cell stack 50) is supplied to the secondary battery 3 through the electric circuit and is also supplied to the motor 4 through the inverter 6.

The fuel cell stack 50 is formed by stacking a plurality of unit cells (all not shown) formed by sandwiching a membrane electrode assembly (Membrane Electrode Assembly, MEA) between conductive separators in the thickness direction. The cells are electrically connected in series. The membrane electrode assembly is one in which an electrolyte membrane (solid polymer membrane) is sandwiched between an anode and a cathode containing a catalyst. The separator is provided with an anode flow channel through which hydrogen gas as fuel flows, a cathode flow channel through which air (oxygen) flows, and a cooling flow channel (not shown) through which cooling water flows. A flow passage 41 is connected to the cooling flow passage, and the cooling water supplied from the cooling device 40 circulates in the fuel cell stack 50.

The hydrogen supply device 20 is a device for supplying hydrogen gas to the fuel cell stack 50 through the hydrogen supply passage 21 connected to the anode flow passage of the fuel cell stack 50. The hydrogen supply device 20 includes a pressure reducing valve, a hydrogen supply device, and the like, and also includes a hydrogen gas tank storing hydrogen gas therein. A valve 23 for controlling the flow state of hydrogen gas is interposed on the hydrogen supply passage 21. Further, a hydrogen discharge path 22 through which the discharged hydrogen gas flows is connected to the downstream end of the anode flow path. A valve 24 is interposed in the hydrogen discharge passage 22 and a recirculation passage 26 in which a pump 25 is interposed is connected. That is, the fuel cell 5 ′ of the present embodiment recovers and recycles the hydrogen flowing out of the fuel cell stack 50.

The air supply device 30 is a device for supplying air to the fuel cell stack 50 through the air supply passage 31 connected to the cathode flow channel of the fuel cell stack 50. The air supply device 30 includes a compressor, an exhaust flow control valve, a humidifier, and the like, and supplies the air taken in by the compressor to the fuel cell stack 50. In addition, on the air supply path 31, the valve 33 which controls the circulation state of air is interposed. Further, an air discharge path 32 through which the discharged air flows is connected to the downstream end of the cathode flow path. A valve 34 is interposed in the air discharge path 32.

In the fuel cell stack 50 configured in this manner, hydrogen is supplied to the anode via the anode flow channel, and air (oxygen) is supplied to the cathode via the cathode flow channel, and is included in the anode and the cathode. Electricity is generated by the occurrence of an electrical reaction on the catalyst. The operation states of the hydrogen supply device 20 and the air supply device 30, the open / close states of the

valves

23, 24, 33, 34, and the operation state of the pump 25 are controlled by the control device 2 '. The fuel cell 5 ′ is provided with a temperature sensor 15 for detecting the temperature of the fuel cell stack 50 and a voltage sensor 16 for detecting the voltage of each cell of the fuel cell stack 50 (hereinafter referred to as “cell voltage”). The information detected by each of the

sensors

15, 16 is transmitted to the control device 2 '.

[2. Control outline]

The control device 2 'of the present embodiment performs charge / discharge control of activating the power transfer device to additionally charge or additionally discharge the secondary battery 3 when a predetermined charge / discharge condition is satisfied while the vehicle 1' is stopped. carry out. It has become clear that, depending on the material of the secondary battery 3, specific deterioration proceeds even if it is not in the overdischarged state or the overcharged state. Specifically, it has been found that when the secondary battery 3 is stored in a state in which the charging rate of the secondary battery 3 is in a range in which the deterioration tends to progress, the deterioration proceeds in the meantime. The charge / discharge control of the present embodiment is implemented to prevent such deterioration.

In the present embodiment, when all of the following conditions 1 to 3 are satisfied, it is determined that the above-mentioned charge and discharge conditions are satisfied. That is, as in the first embodiment, charge / discharge control is performed when all of the conditions 1 to 3 are satisfied while the vehicle 1 'is stopped. In addition, if at least one of the conditions 1 to 3 is not satisfied during the charge / discharge control, the charge / discharge control is ended.
== charge / discharge condition ==
Condition 1: The state of charge SOC of the secondary battery 3 is within a control range corresponding to a predetermined degradation progress range (see FIG. 5)
Condition 2: Vehicle 1 'is in a parked condition Condition 3: External charging is not performed

Condition 3 is a condition provided in view of the fact that if external charging is in progress, even if condition 1 is satisfied when condition 2 is satisfied, then condition 1 should not be satisfied eventually. When the charging gun is inserted into the charging port, communication is started between the vehicle 1 'and the external charging device, so the condition 3 is determined based on this information.

That is, in the charge and discharge control of the present embodiment, the secondary battery 3 is not externally charged even after a while after the vehicle 1 'stops, and the deterioration of the secondary battery 3 is likely to progress. To be implemented. Note that it is sufficient that at least both of the condition 1 and the condition 2 are included in the implementation condition of the charge and discharge control, the condition 3 may be omitted.

In the "parked state" of condition 2, after the vehicle 1 'is stopped, the state where the occupant is absent continues for a certain time or more. That is, even after stopping the vehicle 1 ', the temporary stopping state where the stopping time is short, such as waiting for a signal, waiting for crossing, passenger getting on and off, loading and unloading of the vehicle 1', etc. Not included in the state.

In the present embodiment, as in the first embodiment, when all the following conditions 4 to 8 are satisfied, it is determined that the vehicle 1 'is in the parking state. If at least one of the conditions 4 to 7 is not satisfied after it is determined that the vehicle is in the parking state, it is determined that the vehicle is not in the parking state.
== Parking condition ==
Condition 4: Vehicle speed V is 0 Condition 5: Main power of vehicle 1 'is off (IG-OFF) Condition 6: Shift position is P Condition 7: Passenger to vehicle 1' Is not boarding Condition 8: A predetermined time elapses after Condition 4 to Condition 7 are all satisfied

The "predetermined time" of condition 8 is set to a time longer than the necessary time assumed when waiting for a signal, waiting for crossing or crossing, getting on or off passengers or loading / unloading luggage into / from the vehicle after stopping the vehicle 1 ' Ru. In particular, in the present embodiment, the predetermined time is set to be longer than the time required for the external charge of the secondary battery 3 to start after the occupant of the vehicle 1 a gets off. The predetermined time may be a fixed value, or may be a variable that can be arbitrarily set by the user. In the present embodiment, the predetermined time is set by the time setting unit 10 as a variable value which can be arbitrarily set by the user.

[3. Control configuration]
As shown in FIG. 3, the control unit 2 'is provided with an estimation unit 2A, a parking determination unit 2B, a state determination unit 2C, and a control unit 2D' as elements for performing the above-described charge / discharge control. Each of these elements may be realized by an electronic circuit (hardware), may be programmed as software, or some of these functions may be provided as hardware and the other as software. It may be one. Further, the control device 2 'is provided with a timer for measuring an elapsed time from the time when all the above conditions 4 to 7 are satisfied.

3-1. Estimator]

The estimation unit 2A estimates the charging rate SOC of the secondary battery 3. The charging rate SOC is calculated (estimated) based on, for example, a measured value or an estimated value of the open circuit voltage of the secondary battery 3. Alternatively, it is also possible to calculate (estimate) the charging rate SOC by integrating the charge / discharge current of the secondary battery 3 and tracking the increase / decrease change of the remaining power. In the present embodiment, the ratio of the remaining power to the maximum charge capacity of the secondary battery 3 is expressed as a percentage, which is estimated as the charging rate SOC. The charging rate SOC estimated here is transmitted to the control unit 2D '.

[3-2. Parking judgment section]

The parking determination unit 2B determines whether the vehicle 1 'is in a parking state. About parking judgment part 2B, since it is the same as that of a 1st embodiment, explanation is omitted.

[3-3. State determination unit]

The state determination unit 2C determines the deterioration state of the fuel cell 5 '. In the charge / discharge control of the present embodiment, if the fuel cell 5 ′ is in a deteriorated state while additionally suppressing the deterioration of the secondary cell 3 by additionally charging the secondary cell 3, the performance recovery of the fuel cell 5 ′ is also performed. Plan. That is, the state determination unit 2C determines the deterioration state to determine the necessity of performance recovery of the fuel cell 5 '.

When the fuel cell 5 ′ is operated for additional charging by operating the fuel cell 5 ′, the state determination unit 2C according to the present embodiment operates when the fuel cell 5 ′ is operated to output a desired voltage (hereinafter referred to as “actual It is determined whether or not the fuel cell 5 ′ is in a deteriorated state based on the “voltage value”. The state determination unit 2C of this embodiment uses the cell voltage as the voltage of the fuel cell 5 'and uses the average value or the representative value of the plurality of cell voltage values detected by the voltage sensor 16 as the actual voltage value. .

Specifically, when the fuel cell 5 'is controlled to output a desired voltage by a control unit 2D' described later, a value detected by the state determination unit 2C by the voltage sensor 16 (ie, an actual voltage value) Is obtained, and the deterioration state of the fuel cell 5 'is determined by comparing the actual voltage value with a judgment value lower by a predetermined voltage than the desired voltage value.

As described later, since the fuel cell 5 'is gradually deteriorated by continuous operation for a long time, even if the fuel cell 5' is controlled to output a desired voltage, the desired voltage is actually obtained. The value may not be detected. Therefore, in the present embodiment, it is determined whether or not the fuel cell 5 ′ is in the deteriorated state using the actual voltage value and a determination value that is lower than the desired voltage value by a predetermined voltage. The determination value of the present embodiment is a threshold value for determining whether or not the performance of the fuel cell 5 ′ needs to be recovered, and is preset to a value obtained by subtracting a predetermined voltage from a desired voltage value. The method of setting the determination value is not limited to this. For example, the actual voltage value when the fuel cell 5 'is controlled to output a desired voltage when the previous charge / discharge control is performed is stored, and this value (that is, the previous actual voltage value) It may be set as a judgment value.

State determination unit 2C determines that fuel cell 5 'is in a deteriorated state when the actual voltage value is lower than the determination value, and when the actual voltage value is equal to or higher than the determination value, fuel cell 5' It determines that it is not in the deteriorated state, and transmits the determination result to the control unit 2D '.

The state determination unit 2C of the present embodiment determines the deterioration state of the fuel cell 5 'based on the actual voltage value when the fuel cell 5' is controlled to operate in the highest efficiency operation mode. The highest efficiency operation mode is a mode in which the fuel cell 5 'is operated at the highest cost. That is, the operation mode with the highest output with respect to the consumption of fuel (hydrogen gas) is the highest efficiency operation mode. In the highest efficiency operation mode of the present embodiment, the hydrogen supply device 20, the air supply device 30, the cooling device 40, and the like are controlled to predetermined operation states.

In the highest efficiency operation mode, the fuel cell 5 'is controlled to output a desired voltage (e.g., 0.85 [V]). Here, even if it is not necessary to recover the performance of the fuel cell 5 '(when the fuel cell 5' is not deteriorated so much), actually it gradually deteriorates due to long continuous operation. Even if the output control is performed in this manner, the actual voltage value becomes a value (for example, 0.80 to 0.83 [V]) slightly lower than the desired voltage value. However, in this case, the value does not fall below the above determination value. Therefore, although the fuel cell 5 'is operating in the highest efficiency operation mode, it can be determined that the fuel cell 5' is not deteriorated if the actual voltage value is equal to or higher than the judgment value. If the value is less than the determination value, it can be determined that the fuel cell 5 ′ is degraded.

[3-4. Control unit]

The control unit 2D ′ operates the power transfer device to additionally charge or additionally discharge the secondary battery 3 when the above-mentioned charge / discharge condition is satisfied while the vehicle 1 ′ is stopped. That is, control part 2D 'determines the success or failure of charge / discharge conditions when vehicle 1' stops, and carries out charge / discharge control according to the result of the judgment. The control unit 2D 'determines whether the vehicle 1' has stopped based on, for example, the vehicle speed, the shift position, and the like. As in the first embodiment, the control unit 2D 'of the present embodiment determines whether the vehicle 1' is at a stop based on whether the vehicle speed V is zero.

Control part 2D 'determines said condition 1 using the charging rate SOC estimated by estimation part 2A. Further, the above-mentioned condition 2 is determined using the determination result acquired from the parking determination unit 2B, and the above-mentioned condition 3 is determined based on the communication information with the external charging device.

When all the conditions 1 to 3 are satisfied, the control unit 2D ′ determines that the above-described charge and discharge conditions are satisfied. On the other hand, when at least one of the conditions 1 to 3 described above is not satisfied, the power transfer device is stopped and the charge and discharge control is ended.

When performing charge / discharge control, control unit 2D 'selects whether additional charging or additional discharging is performed based on the charging rate SOC of secondary battery 3 estimated by estimation unit 2A. The method of selecting whether to additionally charge or to additionally discharge is the same as in the first embodiment, and thus the description thereof is omitted. In the present embodiment, the charge / discharge determination threshold SOCth, which is the determination threshold for whether additional charging or additional discharging is performed, is set to a value lower than the intermediate value of the deterioration progress range, not the intermediate value of the deterioration progress range. (See the bottom of Figure 5).

When the additional discharge is performed, the control unit 2D ′ operates the auxiliary battery 9 to perform additional charging while charging the auxiliary battery 9 with the power of the secondary battery 3. On the other hand, when additional charging is performed, control unit 2D 'determines whether additional charging by auxiliary battery 9 is possible, and when additional charging by the auxiliary battery is possible, auxiliary battery 9 is used. The operation is performed to carry out the additional charge, and when the additional charge by the auxiliary battery 9 is not possible, the fuel cell 5 'which is a power generation device is operated to perform the additional charge.

The determination as to whether or not additional charging by the auxiliary battery 9 is possible, and the method of operating the auxiliary battery 9 to perform additional charging are the same as in the first embodiment, and thus the description thereof is omitted. Here, the case where the additional charge is performed and the additional charge by the auxiliary battery 9 can not be performed, that is, the case where the fuel cell 5 ′ is operated to perform the additional charge will be described. When the fuel cell 5 'is operated to perform additional charging, the control unit 2D' starts the fuel cell 5 'and charges the secondary battery 3 with the generated power of the fuel cell 5'. On the other hand, when at least one of the above conditions 1 to 3 is not satisfied during the charge / discharge control, the fuel cell 5 'is stopped and the charge / discharge control is ended.

The control unit 2D 'of this embodiment selects the operation mode of the fuel cell 5' based on the determination result by the state determination unit 2C when the fuel cell 5 'is operated and additional charging is performed, and the fuel mode is selected in the operation mode The battery 5 'is operated to carry out additional charging. Specifically, when the state determination unit 2C determines that the fuel cell 5 'is not in the deteriorated state, the control unit 2D' selects the above-mentioned highest efficiency operation mode, and the state determination unit 2C selects the fuel cell 5 '. The recovery operation mode is selected when it is determined that the vehicle is in the deteriorated state. The recovery operation mode is an operation mode for charging the secondary battery 3 while performing performance recovery of the fuel cell 5 ′.

As described above, fuel cells generally deteriorate due to various factors due to long-term continuous operation. For example, oxidation deterioration of the catalyst of the cathode electrode, deterioration due to chemical adsorption or physical adsorption of deterioration decomposition products derived from the membrane electrode assembly, chemical adsorption or physical adsorption of impurities derived from systems such as metal separators, metal piping, resin piping, etc. Degradation due to chemical adsorption of sulfur and salinity in the atmosphere. By performing the above recovery operation mode, recovery of the state (performance) of the fuel cell 5 ′ thus degraded is achieved. It should be noted that if it is determined that fuel cell 5 ′ is not deteriorated as a result of recovery of fuel cell 5 ′ as a result of execution of the recovery operation mode, all of the above conditions 1 to 3 are satisfied. The controller 2D 'switches the operation mode of the fuel cell 5' from the recovery operation mode to the highest efficiency operation mode.

Control part 2D 'of this embodiment implements "potential cycle control" as a recovery operation mode. In potential cycle control, the voltage of the fuel cell 5 ′ (hereinafter referred to as “impurity removing voltage Vmin”) is lower than the voltage (for example, 0.6 to 0.85 [V]) that the fuel cell 5 ′ can normally output. Control is repeated and control to raise the lowered voltage to near the desired voltage value again. Here, "normal" means that the fuel cell 5 'is operating while the vehicle 1' is traveling.
That is, in the recovery operation mode, the control unit 2D 'of the present embodiment controls the operating state of the fuel cell 5' so that the voltage value of the fuel cell 5 'repeats rising and falling.

The impurity removal voltage Vmin is a voltage value at which the impurity contained in the fuel cell 5 'is removed, and varies depending on the impurity. Here, as described above, the control to lower the voltage of the fuel cell 5 'to the impurity removal voltage Vmin and the control to increase it again are combined into one cycle. The fuel cell 5 ′ is controlled in such a manner that the adsorption of impurities on the catalyst is weakened by controlling the voltage value to the impurity removal voltage Vmin or less, and the impurities are removed from the fuel cell 5 ′ by the flow of gas. Recovery is possible.

The control unit 2D ′ of the present embodiment reduces the impurity removal voltage Vmin (lower limit value) as the number of repetitions (cycle number) of the increase and decrease of the voltage increases. That is, the impurity removal voltage Vmin of the present embodiment is not a constant value, but is a variable value that gradually decreases from a preset initial value. Since the voltage value at which the adsorption of the impurities adsorbed in the fuel cell 5 ′ is weakened varies depending on the type of the adsorbed impurities, the fuel cell 5 ′ can be changed by changing the impurity removal voltage Vmin every cycle as described above. The performance of the fuel cell 5 'can be effectively recovered while suppressing the decrease in the power generation efficiency.

The control unit 2D 'of the present embodiment implements the above-described potential cycle control in the following flow. First, the fuel cell 5 'is controlled to output a desired voltage, and the voltage of the fuel cell 5' is reduced from the actual voltage value at this time to the impurity removal voltage Vmin. Specifically, the control unit 2D ′ reduces the velocity of the hydrogen gas sent from the hydrogen supply device 20 and the velocity of the air sent from the air supply device 30, and the flow rate of the cooling water sent from the cooling device 40. Reduce

When the flow rate of the cooling water sent from the cooling device 40 to the fuel cell stack 50 decreases, the cooling is suppressed and the temperature of the fuel cell stack 50 rises without the heat of reaction between hydrogen and oxygen being dissipated in the fuel cell stack 50. Do. When the temperature of the fuel cell stack 50 is increased, the anode catalyst layer is dried to suppress the reaction of hydrogen in the anode catalyst layer. Furthermore, since the velocity of the gas circulating in the fuel cell stack 50 is reduced, hydrogen gas and air stagnate in the fuel cell stack 50. This reduces the voltage.

Then, when the voltage value detected by voltage sensor 16 becomes lower than impurity removal voltage Vmin, control unit 2D ′ maintains the state for a predetermined time, and causes fuel cell 5 to raise the voltage to a desired voltage value again. Control the '. That is, the control unit 2D 'controls the hydrogen supply device 20, the air supply device 30, the cooling device 40, and the like so that the fuel cell 5' outputs a desired voltage (0.85 [V] in the present embodiment).

The control unit 2D 'causes the state determination unit 2C to determine whether the performance of the fuel cell 5' has recovered after the fuel cell 5 'has been operated for one cycle in the recovery operation mode. That is, when fuel cell 5 'is controlled such that fuel cell 5' outputs a desired voltage by control unit 2D 'and the voltage of fuel cell 5' is increased again, state determination unit 2C determines the actual voltage A value is acquired and compared with the determination value to determine the deterioration state. Note that whether or not the voltage of the fuel cell 5 'is raised again can be determined by estimating it from the amount of change in voltage.

When the actual voltage value is lower than the determination value, the state determination unit 2C determines that the fuel cell 5 'is in the deteriorated state (that is, the performance is not recovered), and transmits the result to the control unit 2D'. Do. In this case, the control unit 2D ′ lowers the impurity removal voltage Vmin by a predetermined amount dV to change it to the impurity removal voltage Vmin ′. Then, the voltage of the fuel cell 5 'is lowered and raised again, and the same process as described above is repeated. On the other hand, when the actual voltage value is equal to or higher than the determination value, the state determination unit 2C determines that the fuel cell 5 'is not in the deteriorated state (that is, the performance is recovered), and transmits the result to the control unit 2D'. . In this case, the control unit 2D 'switches the operation mode of the fuel cell 5' from the recovery operation mode to the highest efficiency operation mode if the

above conditions

1 and 3 are satisfied. Further, the control unit 2D ′ resets the impurity removal voltage Vmin to an initial value.

FIG. 5 shows the change in voltage value of the fuel cell 5 'when the fuel cell 5' is operated and additional charging is performed as the charge / discharge control of the present embodiment, and the charge ratio SOC of the secondary cell 3 accompanying it. It is a chart which illustrates the change of. In Figure 5, the charge and discharge conditions at time t ₀ additional charging by operating the fuel cell 5 'is started as the charge and discharge were controlled satisfied, it is determined whether the deteriorated state is performed at time t ₁ The case is illustrated. FIG. 5 shows an example in which it is determined that the fuel cell 5 ′ is not in the deteriorated state when the recovery operation mode is performed for three cycles (time t ₄ ). The solid line in the figure shows the case where the fuel cell 5 'is operated in the recovery operation mode, and the broken line in the figure shows the case where the fuel cell 5' is operated in the highest efficiency operation mode.

When the fuel cell 5 'is operated in the highest efficiency operation mode to additionally charge the secondary battery 3, as shown by the broken line in FIG. 5, the secondary battery 3 continues to be charged at a predetermined voltage. The charging rate SOC of the secondary battery 3 rises in proportion to the charging operation time. In FIG. 5, the fuel cell 5 'is operated in the highest efficiency operation mode even after the charge rate SOC deviates from the control range, but the fuel cell 5' is stopped when the charge rate SOC deviates from the control range You may

On the other hand, when the fuel cell 5 'is operated in the recovery operation mode to additionally charge the secondary cell 3, as shown by the solid line in FIG. 5, the secondary cell 3 mainly comprises the fuel cell 5'. It is charged when the voltage value is constant or falling. Therefore, when the fuel cell 5 'is operated in the recovery operation mode to charge the secondary battery 3, the charging rate SOC of the secondary battery 3 is intermittently increased according to the charging execution time. The rate of increase is lower than in the case of operating the fuel cell 5 ′ in the highest efficiency operation mode to charge the secondary battery 3.

In addition, as described above, the control unit 2D ′ reduces the impurity removal voltage Vmin by a predetermined amount dV each cycle to change it to the impurity removal voltages Vmin ′ and Vmin ′ ′. For example, the voltage value of the fuel cell 5 ′ lower limit, than at time t ₁ ~ t _2, who at time t ₂ ~ t ₃ is low, 1 lower each time it is cycle control. Thus, the power generation efficiency of the fuel cell 5 ' The impurities contained in the fuel cell 5 'are removed while suppressing the decrease, and the performance is recovered. Even if the performance of the fuel cell 5' is recovered, the charging rate SOC of the secondary cell 3 is in the control range In this case, the recovery operation mode is switched to the highest efficiency operation mode, and the operation of the fuel cell 5 'is continued.

[4. flowchart]

FIG. 6 is a sub-flow chart example of the flow chart of FIG. 2 for explaining a part of the contents of the above-mentioned charge and discharge control. This sub-flowchart is implemented in place of steps S9 to S11 of FIG. As in the first embodiment, in the present embodiment, when the vehicle 1 'stops, external charging is not performed, and conditions 4 to 7 of the above-mentioned parking conditions are satisfied. The flowchart is started in the control device 2 'and is performed at a predetermined operation cycle while the vehicle 1' is stopped. The sub-flowchart of FIG. 6 is carried out when it is determined in step S5 of the flow chart of FIG. 2 that the auxiliary battery 9 can not perform additional charging. Note that the above predetermined time is assumed to be input (set) in advance by the user.

In step S9 ', the fuel cell 5' is activated. In step S10 ', it is determined whether the fuel cell 5' is in a deteriorated state. Specifically, the state determination unit 2C acquires an actual voltage value when the fuel cell 5 is controlled to output a desired voltage, and determines whether the actual voltage value is less than the determination value. Be done. If it is determined in step S10 'that the fuel cell 5' is not in the deteriorated state, the process proceeds to step S11 '. If it is determined that the fuel cell 5' is in the deteriorated state, the process proceeds to step S16 '. After step S11 ', the secondary battery 3 is additionally charged while operating the fuel cell 5' in the highest efficiency operation mode.

That is, in step S11 ', control unit 2D' controls fuel cell 5 'to operate in the highest efficiency operation mode, and secondary battery 3 is additionally charged. In subsequent step S12', the charging rate of secondary battery 3 is SOC is acquired. Furthermore, in step S13 ', it is determined whether the obtained charging rate SOC is within the control range. If it is determined in step S13 'that the state of charge SOC of secondary battery 3 is within the control range, the process returns to step S11', operation in the highest efficiency operation mode is continued, and secondary battery 3 is added Be charged.

Then, if it is determined in step S13 'that the charging rate SOC of secondary battery 3 is not within the control range, secondary battery 3 is out of the charging rate range in which deterioration readily progresses, so fuel cell 5 in step S14'. The operation of 'is stopped, the impurity removal voltage is reset to the initial value in step S15', and this flow is returned. When the process proceeds from step S10 'to step S11', since the impurity removal voltage is not changed from the initial value, the process of step S15 'is not substantially performed.

On the other hand, if it is determined in step S10 'that the fuel cell 5' is in the deteriorated state, the process proceeds to step S16 'to additionally charge the secondary battery 3 while operating the fuel cell 5' in the recovery operation mode. Do.

That is, in step S16 ', control unit 2D' controls fuel cell 5 'to operate in the recovery operation mode, and secondary battery 3 is additionally charged. In subsequent step S17', the charging rate SOC of secondary battery 3 is Is acquired. Furthermore, in step S18 ', it is determined whether the obtained charging rate SOC is within the control range. If it is determined in step S18 'that the state of charge SOC of the secondary battery 3 is within the control range, the process proceeds to step S19' to determine whether the fuel cell 5 'is in a deteriorated state.

In step S19 ', when it is determined that the fuel cell 5' is in a deteriorated state, the process proceeds to step S20 ', and the impurity removal voltage when performing the recovery operation mode is changed. For example, when the current impurity removal voltage is Vmin, a value Vmin '(= Vmin-dV) obtained by subtracting the predetermined amount dV from the value Vmin is set as a new impurity removal voltage. Thereafter, the process returns to step S16 ', and the fuel cell 5' is controlled again in the recovery operation mode by the control unit 2D 'to carry out additional charging of the secondary battery 3.

If it is determined in step S19 'that the fuel cell 5' is not in the deteriorated state before it is determined in step S18 'that the state of charge SOC of the secondary battery 3 is not within the control range, steps S19' to S11 are performed. And the fuel cell 5 'is controlled to operate in the highest efficiency mode of operation. That is, after the performance recovery of the fuel cell 5 'is completed, the additional charging of the secondary cell 3 is continued while operating the fuel cell 5' in the most efficient operation mode.

On the other hand, if it is determined in step S18 'that the state of charge SOC of secondary battery 3 is not within the control range, secondary battery 3 is out of the charging range where deterioration easily progresses, so in step S14' the fuel cell The 5 'operation is stopped, the impurity removal voltage is reset to the initial value in step S15', and this flow is returned.

[5. Action, effect]

(1) In the control device 2 'of the vehicle 1' described above, the vehicle 1 'is in a parked state while the vehicle 1' is at a stop, and the state of charge SOC estimated by the estimation unit 2A is the full charge range and the empty When charge / discharge conditions are satisfied including a control range corresponding to a predetermined deterioration progress range excluding the charge range, the power transfer device operates to additionally charge or additionally discharge the secondary battery 3 . As a result, the deterioration of the secondary battery 3 can be suppressed, and a decrease in the cruising distance of the vehicle 1 'can be prevented.
(2) Further, since the fuel cell 5 'is mounted on the vehicle 1' described above as a power transfer device, the vehicle 1 'is provided with consideration for the environment while suppressing the deterioration of the secondary battery 3. It becomes possible.

(3) In the above-described control device 2 ', when the fuel cell 5' is operated and additional charging is performed and the state determination unit 2C determines that the fuel cell 5 'is in the deteriorated state, the fuel The fuel cell 5 'is operated in the recovery operation mode for recovering the performance of the cell 5' to perform additional charging. As a result, deterioration of the secondary battery 3 can be suppressed, and at the same time, the performance of the fuel cell 5 ′ can be recovered.

(4) In the above-described control device 2 ', when the fuel cell 5' is operated to perform additional charging, and the fuel cell 5 'is determined not to be deteriorated by the state determination unit 2C, 5 'operates in the highest efficiency mode of operation and additional charging is performed. As described above, by operating the fuel cell 5 ′ in the highest efficiency operation mode, which is the operation mode in which the output with respect to the consumption of fuel (hydrogen gas) is the highest, the consumption of expensive fuel (hydrogen gas) is suppressed. Additional charging of the secondary battery 3 can be performed.

(5) In the control device 2 'of the vehicle 1' described above, when the fuel cell 5 'is operated for additional charging, the actual voltage value when the fuel cell 5' is operated to a desired voltage is used. Based on this, it is determined whether or not the fuel cell 5 'is in a deteriorated state. Thus, the deterioration state of the fuel cell 5 'can be easily determined, and the control configuration can be simplified.

(6) The control unit 2D 'described above performs potential cycle control to control the fuel cell 5' so that the voltage of the fuel cell 5 'repeats rising and falling as a recovery operation mode. Thus, by forcibly reducing the voltage of the fuel cell 5 ', the adsorption power of the impurities adhering to the catalyst of the fuel cell 5' is weakened, and the impurities are absorbed by the fuel cell 5 '. Removed from That is, the impurities contained in the fuel cell 5 'can be removed, and the performance of the fuel cell 5' can be recovered.

(7) In the above-described control device 2 ', in the recovery operation mode, the voltage of the fuel cell 5' is lowered to a predetermined lower limit value, and the number of repetitions of the voltage rise and fall of the fuel cell 5 'increases. Lower the lower limit. The voltage value at which the adsorptive power of the impurities adsorbed in the fuel cell stack 50 is weakened varies depending on the type of the adsorbed impurities. On the other hand, forcibly reducing the voltage of the fuel cell 5 'is not preferable from the viewpoint of the power generation efficiency. Therefore, by reducing the lower limit (impurity removing voltage Vmin) every cycle as described above, impurities can be removed while suppressing a decrease in power generation efficiency, so performance recovery of the fuel cell 5 'can be more effectively performed. Is possible.

Further, in the control device 2 'described above, the condition for determining that the vehicle 1' is in the parking state includes that a predetermined predetermined time has elapsed from the time when the other conditions for determining the parking state are satisfied. Be Furthermore, this predetermined time is set to be equal to or longer than the time required to start the external charging of the secondary battery 3 after the passenger of the vehicle 1 ′ dismounts. That is, charge and discharge control is performed when secondary battery 3 is not externally charged even after a while for a while after vehicle 1 'stops. Thus, for example, when the stop time is short, such as waiting for a signal or waiting for a level crossing, charge / discharge control is not performed, and is not performed even when the user has an intention to perform external charging. As described above, contrary to the user's intention, the control device 2 'does not perform the additional charge of the secondary battery 3, so that the consumption of the expensive fuel (hydrogen gas) can be suppressed.

[6. Modified example]

In the above-described embodiment, the voltage of the fuel cell 5 'is used as the cell voltage, and the deterioration state of the fuel cell 5' is determined based on the cell voltage. However, the voltage of the fuel cell 5 'is not limited to the cell voltage. For example, the voltage of the power generated by the fuel cell 5 'is the voltage of the fuel cell 5', a voltage sensor is provided between the wiring of the fuel cell 5 'and the secondary cell 3, and the deterioration state of the fuel cell 5' is You may determine based on the voltage acquired from the sensor. Further, the parameter for determining the deterioration state is not limited to the voltage. For example, a current sensor that acquires the current of the fuel cell 5 ′ may be provided, and the state determination may be performed by estimating the deterioration state of the fuel cell 5 ′ from the acquired current value.

In the embodiment described above, the case where the control unit 2D 'performs potential cycle control as the recovery operation mode has been described, but the operation method for recovering the performance of the fuel cell 5' is not limited to the potential cycle control. For example, instead of the potential cycle control, over-humidification control may be performed to control the fuel cell 5 ′ so as to increase the humidity in the fuel cell 5 ′. Alternatively, instead of the potential cycle control, high flow rate control may be performed in which the flow rate of the gas flowing through the fuel cell 5 ′ is increased.

In the over-humidifying control, the fuel cell 5 'is cooled more than usual by controlling the fuel cell 5' so as to increase the flow rate of the cooling water flowing in the fuel cell 5 ', and the fuel cell 5' is internally cooled. Lower the temperature of As a result, the water produced by reaction in the fuel cell 5 'is condensed, and the impurities are adsorbed in the condensed water, and are carried out of the fuel cell 5' on the gas flow. Thus, the performance of the fuel cell 5 'can be recovered.

Further, in the high flow rate control, by increasing the flow rate of the gas (air, hydrogen) flowing in the fuel cell 5 ', the impurities in the fuel cell 5' are easily discharged to the outside of the fuel cell 5 '. Performance can be recovered. When the recovery operation mode is selected, the control unit 2D ′ may be implemented by combining two or all of the above-described potential cycle control, over humidification control, and alternating current amount control.

Although the fuel cell is described as a polymer electrolyte fuel cell (PEFC) in the above-described embodiment, the type of fuel cell is not limited thereto. For example, solid oxide fuel cell (SOFC; Solid Oxide Fuel Cell), molten carbonate fuel cell (MCFC; Molten Carbonate Fuel Cell), phosphoric acid fuel cell (PAFC; Phosphoric Acid Fuel Cell), alkaline electrolyte fuel It is also possible to apply the charge / discharge control described above to a vehicle 1 'equipped with a battery (AFC; Alkaline Fuel Cell). Further, in the embodiment described above, the case where the fuel cell 5 'is used as the power generation device is illustrated, but instead of or in addition to the fuel cell 5', an engine and a generator may be used as the power generation device.

[7. Other]

The configurations of the vehicles 1 and 1 'and the configurations of the control devices 2 and 2' described above are merely examples, and are not limited to the configurations described above. The charge / discharge conditions for starting the additional charge or the additional discharge, and the contents of the operation mode of the fuel cell 5 'selected at the time of the additional charge are also examples, and are not limited to those described above.

For example, the charge condition for starting the additional charge or the additional discharge may include at least both the condition 1 and the condition 2 described above, and may include conditions other than the condition 1 to the condition 3 .

1, 1 'Vehicle 2, 2' control device 2A estimation unit 2B parking determination unit 2C

state determination unit

2D, 2D 'control unit 3 secondary battery 4 motor 5 generator (power generation device, power transfer device)
5 'Fuel cell (power generator, power transfer device)
6 inverter 7 converter 8 engine 9 auxiliary battery (power transfer device)
9s selector switch 10 time setting means 11 vehicle speed sensor 12 ignition switch 13 shift position sensor 14 load sensor 50 fuel cell stack 20 hydrogen supply device 30 air supply device

Claims

A control device of a vehicle comprising: a chargeable / dischargeable secondary battery; and a power exchange device capable of at least one of power supply to the secondary battery and power reception from the secondary battery.
An estimation unit configured to estimate a charging rate of the secondary battery;
A parking determination unit that determines whether the vehicle is in a parked state;
A control unit that operates the power transfer device to additionally charge or additionally discharge the secondary battery when a predetermined charge / discharge condition is satisfied;
For the charge / discharge condition, it is determined that the vehicle is in the parked state by the parking determination unit, and the charge rate estimated by the estimation unit is a predetermined value excluding the full charge range and the idle charge range A control device for a vehicle, including being within a control range corresponding to the degradation progress range of the vehicle.
The control unit performs the additional discharge when the charge rate is less than a predetermined charge / discharge determination threshold within the deterioration progress range when the charge / discharge condition is satisfied, and the charge rate is the charge / discharge determination threshold The control device for a vehicle according to claim 1, wherein the additional charging is performed when it is above.
The power transfer device includes a chargeable / dischargeable auxiliary battery mounted on the vehicle,
The said control part operates the said auxiliary | assistant battery, and performs the said additional discharge, charging the said auxiliary | assistant battery by the electric power of the said secondary battery, when performing the said additional discharge, It is characterized by the above-mentioned. Vehicle control device.
The power transfer device includes a power generation device capable of charging the secondary battery,
The control unit determines whether the additional charging by the auxiliary battery is possible when the additional charging is performed, and operates the auxiliary battery when the additional charging by the auxiliary battery is possible. 4. The control device for a vehicle according to claim 3, wherein the additional charging is performed, and when the additional charging by the auxiliary battery can not be performed, the power generation device is operated to perform the additional charging.
The control device of a vehicle according to claim 4, wherein the power generation device is a fuel cell.
The power transfer device includes a fuel cell mounted on the vehicle,
The control device for a vehicle according to any one of claims 1 to 3, wherein the control unit operates the fuel cell when the additional charge is performed.
A state determination unit that determines a deterioration state of the fuel cell;
The control unit restores the performance of the fuel cell when the fuel cell is operated and the additional charge is performed, and the state determination unit determines that the fuel cell is in a deteriorated state. The control device for a vehicle according to claim 5 or 6, wherein the additional charge is performed by operating the fuel cell in a recovery operation mode.
The control unit operates the fuel cell to perform the additional charge, and when the state determination unit determines that the fuel cell is not in the deteriorated state, the fuel cell is operated in the highest efficiency operation mode. The control device for a vehicle according to claim 7, characterized in that the additional charge is performed to operate.
When the fuel cell is operated and the additional charge is performed, the state determination unit degrades the fuel cell based on an actual voltage value when the fuel cell is operated to a desired voltage. The control device for a vehicle according to claim 7 or 8, characterized in that it is determined whether or not.
10. The controller according to any one of claims 7 to 9, wherein the control unit controls the operating state of the fuel cell such that the voltage of the fuel cell repeatedly rises and falls in the recovery operation mode. The control device of a vehicle according to claim 1.
In the recovery operation mode, the control unit lowers the voltage of the fuel cell to a predetermined lower limit value, and lowers the lower limit value as the number of repetitions of increase and decrease of the voltage increases. The control device of the vehicle according to claim 10.
12. The vehicle-mounted vehicle according to claim 1, wherein the determination condition that the parking determination unit determines that the vehicle is in the parked state includes that a main power supply of the vehicle is in an off state. The control apparatus of the vehicle as described in a term.
The control device for a vehicle according to claim 12, wherein the determination condition that the parking determination unit determines that the vehicle is in the parked state includes that an occupant does not board the vehicle.
The control device for a vehicle according to claim 12 or 13, wherein the parking determination unit determines that the vehicle is in the parking state when the determination condition is satisfied continuously for a predetermined time or more.
15. The control device for a vehicle according to claim 14, further comprising time setting means for setting the predetermined time.