JP2007294294A - Operation control device of fuel cell - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an operation control device of a fuel cell capable of restraining excessive repetition of startup and stoppage of the fuel cell as well as restraining fall of drive voltage of a power storage means at attachment driving for a cargo work. <P>SOLUTION: The operation control device of the fuel cell 1 is provided with a power storage means 2 storing power generated, a power generation volume control means 3 controlling a power generation volume, and a first operation volume detecting means 7 detecting an operation volume of a first operating means 6 capable of controlling action of an attachment for a cargo work in accordance with operation volume. The power generation control means 3 controls a generation volume of the fuel cell 1 to charge the power storage means 2, if a power stored in the power storage means 2 is smaller than a given value, and is able to control a power generation volume by the fuel cell 1 to charge the power storage means 2 based on a detection result by the first operation volume detecting means 7, if a power stored in the power storage means 2 is above the given value. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an operation control device for a fuel cell in an industrial vehicle driven by electric power generated using the fuel cell.

In recent years, development for using electric power generated using a fuel cell as a drive source for an electric device, a vehicle, or the like has been advanced. The electric vehicle using the fuel cell disclosed in Patent Document 1 determines the required power generation current of the fuel cell based on the power required for driving the vehicle, and then determines the actual power generation current. It has means to control the fuel cell's generated current to increase or decrease periodically, ensuring the required power required by the electric vehicle and changing the generated current periodically to change the power generation efficiency The self-heat generation amount can be adjusted, and this makes it possible to speed up the warm-up operation.
JP 2002-313388 A

  However, in the fuel cell operation control method in the fuel cell vehicle described in Patent Document 1, when the vehicle is driven, the generated current of the fuel cell is determined without considering the power stored in the power storage means. Since the power storage means is charged, it is necessary to frequently start and stop the fuel cell. Therefore, the fuel cell is likely to be deteriorated, and there is a risk of shortening the life.

  On the other hand, in view of such a problem, a method of generating power from the fuel cell only when the electric power stored in the power storage means becomes equal to or lower than a predetermined value is also conceivable. However, according to this method, when the electric power required for driving the vehicle suddenly increases, the voltage drop of the power storage means becomes large, and there is a possibility that the driving of the vehicle becomes unstable due to a drop below the voltage required for driving. .

  In particular, in industrial vehicles, the attachment for loading and unloading that is loaded with a high load is also driven along with the driving of the vehicle, so the power required to drive the entire vehicle when lifting and lowering a heavy load Often increases rapidly and is greatly affected by the voltage drop of the storage means. Further, since such an operation is repeatedly performed, deterioration of the fuel cell due to repeated start-stop of the fuel cell as described above tends to be a problem.

  In view of the above circumstances, the present invention is a fuel cell operation control device in an industrial vehicle driven by electric power generated using a fuel cell, and suppresses excessive repetition of start and stop of the fuel cell and cargo handling. It is an object of the present invention to provide a fuel cell operation control device capable of suppressing a decrease in the drive voltage of the power storage means during the attachment drive.

Means and effects for solving the problems

  The present invention relates to an operation control device for a fuel cell in an industrial vehicle driven by electric power generated using the fuel cell. The fuel cell operation control apparatus according to the present invention has the following features to achieve the above object, and includes the following features singly or in combination as appropriate.

  In order to achieve the above object, a first feature of a fuel cell operation control device of the present invention is a fuel cell operation control device in an industrial vehicle driven by electric power generated using a fuel cell, wherein the fuel cell Power storage means for storing electric power generated using a battery, power generation amount control means for controlling the power generation amount of the fuel cell, and first operation means capable of controlling the operation of the cargo handling attachment of the industrial vehicle according to the operation amount First operation amount detection means for detecting the operation amount of the fuel cell, and the power generation amount control means, when the power stored in the power storage means is smaller than a predetermined value, the power generation amount of the fuel cell When the electric power stored in the electric storage means is greater than or equal to the predetermined value, the power generation by the fuel cell is performed based on the detection result by the first operation amount detection means. Control to the is that it is capable of charging the accumulator unit.

According to this configuration, when the power stored in the power storage means by the power generation amount control means is smaller than a predetermined value, the power storage means is charged by the power generation of the fuel cell. Can be increased to a predetermined value or more to suppress a decrease in driving voltage.
Further, when the power stored in the power storage means is equal to or greater than the predetermined value, charging is possible based on the operation amount of the first operation means that is the detection result by the first operation amount detection means. Therefore, when it is determined that the power storage means does not need to be charged based on the operation amount, the fuel cell is not started and can be maintained in a stopped state, and the number of repetitions of starting and stopping of the fuel cell can be reduced. Therefore, it is possible to suppress deterioration of the fuel cell.
Similarly, even when the power stored in the power storage means is equal to or greater than a predetermined value, if it is determined that the power storage means needs to be charged based on the operation amount, the power storage means can be charged. However, it is possible to suppress a drop in drive voltage that can be supplied for driving an industrial vehicle. As a result, it is possible to suppress the operation of the cargo handling attachment from becoming unstable due to insufficient drive voltage.
In addition, since the electric power stored by the power storage means is used as a driving force, the driving electric power of the vehicle can be supplied without time lag with respect to the operation of the industrial vehicle.

  The second feature of the fuel cell operation control apparatus of the present invention is further provided with second operation amount detection means for detecting an operation amount of the second operation means capable of controlling the traveling speed of the industrial vehicle according to the operation amount. The power generation amount control means, when the power stored in the power storage means is equal to or greater than the predetermined value, based on the detection result by the first operation amount detection means and the second operation amount detection means, That is, the power storage means can be charged by controlling the amount of power generated by the battery.

According to this configuration, when the electric power stored in the power storage means is equal to or greater than the predetermined value, the first operation means capable of controlling the operation of the cargo handling attachment and the second operation means capable of controlling the traveling speed of the industrial vehicle. When it is determined that charging of the power storage means is unnecessary based on the operation amount, the fuel cell is not started and can be maintained in a stopped state, and the number of times of starting and stopping the fuel cell can be reduced. Therefore, it is possible to suppress deterioration of the fuel cell.
Further, even when the electric power stored in the power storage means is equal to or greater than a predetermined value, the operation amount of the first operation means capable of controlling the operation of the cargo handling attachment and the second operation means capable of controlling the traveling speed of the industrial vehicle. If it is determined that the power storage means needs to be charged based on the above, charging can be performed, and a decrease in drive voltage that can be supplied by the power storage means for driving the industrial vehicle can be suppressed. In this way, since it is possible to determine whether or not the fuel cell needs to be started in consideration of the influence of the driving of the vehicle, it is possible to make a more appropriate determination according to the operation. Therefore, it is possible to more reliably suppress the running of the vehicle and the operation of the cargo handling attachment from becoming unstable due to insufficient drive voltage.

  According to a third feature of the fuel cell operation control apparatus of the present invention, the power generation amount control means is configured such that when the electric power stored in the power storage means is equal to or greater than the predetermined value, the operation amount of the first operation means is predetermined. When it is greater than or equal to a predetermined first prescribed operation amount, or when the operation amount of the second operation means is greater than or equal to a predetermined second prescribed operation amount, or the second operation means and the first operation The power storage means is charged by controlling the amount of power generated by the fuel cell only when the means are operated simultaneously.

  According to this configuration, when the electric power stored in the power storage means is equal to or greater than a predetermined value, the operation amount of the operation means for controlling the operation of the cargo handling attachment and the first specified operation amount are compared in magnitude and traveling Comparison between the operation amount of the operation means for controlling the speed and the second specified operation amount, and the first operation means for controlling the operation of the cargo handling attachment and the second operation for controlling the traveling speed The necessity of starting the fuel cell can be easily determined by determining whether or not the means are operated at the same time, and can be implemented by a simple control mechanism, and the control mechanism can be easily manufactured. Also, in industrial vehicles, when the attachment for loading and unloading is performed at the same time, the power consumption increases particularly. However, in this case, the fuel cell is always activated, so the vehicle voltage is insufficient due to insufficient drive voltage. It is possible to prevent the running and operation of the cargo handling attachment from becoming unstable.

  According to a fourth aspect of the fuel cell operation control apparatus of the present invention, when the second operating means and the first operating means are operated simultaneously, the operation amount of the first operating means and the second operating means Only when the combined value with the manipulated variable is equal to or greater than a predetermined value, the amount of power generated by the fuel cell is controlled to charge the power storage means.

  According to this configuration, even when the operation of the first operation means and the operation of the second operation means are performed at the same time, the power consumption may be small if the respective operation amounts are small. When the total value of the operation amount and the operation amount of the second operation means is smaller than a predetermined value, unnecessary start-up of the fuel cell can be further suppressed by not starting the fuel cell.

  A fifth feature of the fuel cell operation control apparatus of the present invention is a drive that is electric power required to drive the industrial vehicle based on detection results by the first operation amount detection means and the second operation amount detection means. The power generation amount control means further includes a required power calculation means for calculating the required power, and when the power stored in the power storage means is greater than or equal to the predetermined value, the required power calculation means calculates the required drive power calculated by the required power calculation means. Based on this, the amount of power generated by the fuel cell can be controlled to charge the power storage means.

  According to this configuration, it is necessary for driving the industrial vehicle according to the operation amount of the first operating means and the second operating means by the required power calculating means when the electric power stored in the power storage means is greater than or equal to a predetermined value. The power consumed, that is, the power consumed by driving is calculated. Therefore, it is possible to determine whether or not the fuel cell needs to be activated in consideration of the total energy required for driving the entire industrial vehicle, and it is possible to determine the necessary amount of power generated by the fuel cell. As a result, unnecessary start and stop of the fuel cell can be further suppressed, and control can be performed efficiently.

  A sixth feature of the fuel cell operation control apparatus of the present invention is further provided with a cargo handling load detecting means for detecting a cargo handling load of the industrial vehicle, wherein the required power calculating means includes the first operation amount detecting means and the cargo handling. From the detection result by the load detection means, the cargo handling power which is the power necessary for the operation of the cargo handling attachment of the industrial vehicle is calculated, and from the detection result by the second operation amount detection means and the cargo handling load detection means, the industrial vehicle The travel power, which is the power necessary for the travel, is calculated, and the required drive power is calculated based on the cargo handling power and the travel power.

  According to this configuration, since the required driving power is calculated in consideration of the cargo handling load applied to the industrial vehicle, the calculated required driving power is actually consumed compared to the case where the calculation is performed without considering the cargo handling load. The power can be made closer, and the required driving power can be calculated with high accuracy. Therefore, the drive voltage shortage can be more reliably suppressed, and unnecessary start-up of the fuel cell can be suppressed.

  A seventh feature of the fuel cell operation control device of the present invention is that the power generation amount control means calculates the required power calculation means when the electric power stored in the power storage means is equal to or greater than the predetermined value. When the required driving power is larger than the predetermined specified power, the amount of power generated by the fuel cell is controlled based on the required driving power to charge the power storage means.

  According to this configuration, the necessity of starting the fuel cell can be easily determined by comparing the required drive power calculated by the required power calculation means with the specified power, and can be implemented with a simple control mechanism. is there.

  An eighth feature of the fuel cell operation control apparatus of the present invention is that the power generation amount control means calculates the required power calculation means when the electric power stored in the power storage means is equal to or greater than the predetermined value. When the required driving power is larger than the prescribed power determined based on the power stored in the power storage means, the amount of power generated by the fuel cell is calculated based on the required driving power and the power stored in the power storage means. Controlling and charging the power storage means.

  According to this configuration, the specified power to be compared with the drive required power calculated by the required power calculation unit changes according to the power stored in the power storage unit. Since it is determined whether or not the fuel cell needs to be started up by comparing the specified power with the calculated required driving power, it is possible to make a determination suitable for the state of charge of the power storage means at the time when the necessity of starting up is determined. . Thereby, unnecessary starting of the fuel cell can be further suppressed.

  A ninth feature of the fuel cell operation control apparatus according to the present invention is the fuel cell operation control apparatus for a forklift that travels and raises and lowers the fork with electric power generated using the fuel cell, wherein the first operation amount The detecting means is a detecting means for detecting an operation amount of a cargo handling lever for raising and lowering a fork of the forklift.

  According to this configuration, it is possible to stably perform the traveling and lifting operation of the forklift that consumes a large amount of power by lifting and lowering the fork loaded with luggage.

  The best mode for carrying out the present invention will be described below with reference to the drawings. The fuel cell operation control device according to the embodiment of the present invention can be widely applied as a fuel cell operation control device that generates driving power for an industrial vehicle. In the description of the present embodiment, a fuel cell operation control device that generates electric power for driving a forklift that is an industrial vehicle will be described as an example.

(First embodiment)
FIG. 1 is a diagram showing a configuration of a control system in which an operation control device for a fuel cell according to a first embodiment of the present invention is used in a forklift that is an industrial vehicle.
The forklift moves a fork (loading attachment) attached to the mast up and down along the mast by a lift cylinder that is a hydraulic cylinder. The hydraulic pump for operating the lift cylinder is driven by the cargo handling motor 5. The cargo handling motor 5 is controlled according to the operation amount of the cargo handling lever 6 (first operation means), and the operator can raise and lower the fork by operating the cargo handling lever 6. The forklift includes a traveling motor 8 that is controlled in accordance with the amount of depression of the accelerator pedal 9 (second operating means), and performs traveling driving by driving the traveling motor 8. The operator can drive the forklift by depressing the accelerator pedal 9, and can control the traveling speed according to the amount of depression. Driving power for the cargo handling motor 5 and the traveling motor 8 is supplied from the battery 2 (power storage means).

  Further, by using a regenerative brake as a brake for braking the driving of the traveling motor 8, it is possible to convert the kinetic energy at the time of driving the motor into electric energy and charge the battery 2. In addition, the battery 2 is not limited to the power storage means, and other power storage means such as a capacitor can be used. Further, the driving control of the traveling motor 8 is not limited to being performed by operating the accelerator pedal 9, but can be performed by operating a direction lever or the like.

  The fuel cell operation control apparatus according to the first embodiment includes a fuel cell 1, a battery 2 (power storage unit) that can charge power generated by the fuel cell 1, and a power generation amount control that controls the power generation amount of the fuel cell 1. Means 3, a lever position sensor 7 (first operation amount detection means) for detecting the operation amount of the cargo handling lever 6, and an accelerator opening sensor 10 (second operation amount detection means) for detecting the depression amount of the accelerator pedal 9. Have

The fuel cell 1 may be of a solid polymer electrolyte type, for example. Hydrogen as a fuel gas supplied from a hydrogen tank (not shown) with the flow rate adjusted by a regulating valve or the like, and a compressor (not shown) Power) is generated by an electrochemical reaction with oxygen in the air supplied by
The power generation amount control means 3 is constituted by, for example, a microcomputer, and is a voltage that can be output from the battery 2. The battery voltage corresponding to the electric power stored in the battery 2 is detected and input, and the lever position sensor 7 The detection result by the accelerator opening sensor 10 is input. The power generation amount control means 3 controls the supply amount of hydrogen and oxygen by controlling a regulating valve, a compressor, and the like based on the input information, and controls the power generation amount in the fuel cell 1. It is also possible to perform feedback control while detecting the power generation voltage of the fuel cell 1.

FIG. 2 shows a specific control flow by the fuel cell operation control apparatus according to the first embodiment. The control flow shown in FIG. 2 is executed when the cargo handling lever 6 or the accelerator pedal 9 is operated. It is also possible to set to execute at regular intervals.
In the present embodiment, the battery voltage upper limit value V1 and the battery voltage lower limit value V3, which are predetermined values used for comparison with the battery voltage of the battery 2, and the target voltage V2, which is the target value of the battery voltage during forklift driving, The prescribed operation amount (first prescribed operation amount) of the cargo handling lever 6 and the prescribed depression amount (second prescribed operation amount) of the accelerator pedal 9 are determined in advance. Hereinafter, the flow of FIG. 2 will be described.

  First, the power generation amount control means 3 compares the battery voltage of the battery 2 with the battery voltage lower limit value V3 (step S101). When the battery voltage is equal to or lower than the battery voltage lower limit value V3, in order to generate power by the fuel cell 1, the power generation amount control means 3 calculates the fuel cell output based on the battery voltage (step S106). Based on the calculated fuel cell output, the power generation amount of the fuel cell 1 is controlled, and power generation of the fuel cell 1 is performed until the battery voltage becomes equal to or higher than the battery voltage upper limit value V1 (steps S107 and S108). Is charged in the battery 2. When the battery voltage exceeds the upper limit value, power generation by the fuel cell 1 is stopped.

  When the battery voltage of the battery 2 is equal to or higher than the battery voltage lower limit value V3, the accelerator depression amount is detected by the accelerator opening sensor 10, and the operation amount of the cargo handling lever 6 is detected by the lever position sensor 7 (step) S102). When the operation amount of the cargo handling lever 6 is equal to or greater than the specified operation amount, the power generation amount control means 3 calculates the power generation amount by the fuel cell 1 (steps S103 and S106). Also, when the accelerator depression amount is equal to or greater than the specified depression amount, the amount of power generated by the fuel cell 1 is calculated (steps S104 and S106). Also, when the cargo handling lever 6 and the accelerator pedal 9 are operated simultaneously, the amount of power generated by the fuel cell 1 is calculated (steps S105 and S106). When the operation amount of the cargo handling lever 6 is not more than the prescribed operation amount, the accelerator depression amount is not more than the prescribed depression amount, and the cargo handling lever 6 and the accelerator pedal 9 are not operated at the same time, the lift operation of the forklift In addition, the power consumption by the traveling drive is small, it is determined that the power generation by the fuel cell 1 is unnecessary, and the fuel cell 1 is maintained in the stopped state (step S100).

  In the calculation of the power generation amount of the fuel cell 1 (step S106), the power generation amount control means 3 uses the battery voltage, the operation amount of the cargo handling lever 6 and the depression amount of the accelerator pedal 9 so that the battery voltage follows the target voltage V2. The fuel cell output is calculated. Based on the calculated fuel cell output, the power generation amount control means 3 adjusts the amount of hydrogen supplied from the hydrogen tank to the fuel cell 1 by controlling the opening of the adjustment valve, for example, and also adjusts the discharge flow rate of the compressor. The power generation amount of the fuel cell 1 is controlled by adjusting the amount of air supplied to the fuel cell 1 (step S107). When the driving operation of the forklift is finished, the power generation of the fuel cell 1 is performed until the battery voltage becomes equal to or higher than the upper limit value V1, and then stopped (steps S107, S108, S100).

  FIG. 3 shows a load handling lever operation amount (a), a forklift drive output (b), a battery voltage (c), and an operating state (d) of the fuel cell when the load handling lever 6 is operated more than a specified operation amount. It is a figure which shows a time change. In the figure showing the battery voltage and the operating state of the fuel cell, the state in which the fuel cell is controlled using a control method for starting the fuel cell only when the battery voltage falls below a specified lower limit is shown by a one-dot chain line as a comparative example. . Further, in the figure showing the operating state of the fuel cell, R0 is the stop state of the fuel cell, R1 is the state where the fuel cell is completely started and the amount of power generation can be controlled, and the state from R0 to R1 is the fuel cell. It is the figure typically shown as a transition state from a stop state to an operation state. The power generation amount of the fuel cell is appropriately adjusted in the state of R1.

As shown in FIG. 3 (a), when the cargo handling lever 6 is operated at time T1, the operation amount is equal to or greater than the specified operation amount (indicated by S1 in FIG. 3 (a)). Even if the voltage is not less than the voltage lower limit value (indicated by V3 in FIG. 3C), the operation of the fuel cell 1 is started (see FIG. 3D), and the battery voltage reaches the target voltage level (FIG. 3C). The power generation amount of the fuel cell is controlled so as to be indicated by V2 in FIG. After the operation is completed at time T3, the operation of the fuel cell is stopped when the battery voltage reaches the upper limit value (indicated by V1 in FIG. 3C).
Thus, since the determination of the start of operation of the fuel cell is performed based on the operation information of the cargo handling lever 6, it is possible to suppress the battery voltage from dropping from the target voltage V2 during forklift driving.

  On the other hand, when the control method for starting the fuel cell is used only when the battery voltage falls below the specified lower limit value, as shown in FIG. 3D, the battery voltage is equal to or higher than the lower limit value V3 at time T1. Therefore, when the fuel cell is stopped and the battery voltage drops and reaches the lower limit value V3 at time T2, the operation of the fuel cell is started (see FIG. 3D). Thus, since the start of operation of the fuel cell is delayed as compared with the case where the present invention is used, the drop in the battery voltage from the target voltage level V2 becomes large (see FIG. 3C).

  As described above, by using the fuel cell operation control device according to the first embodiment, when the battery voltage of the battery 2 is smaller than a predetermined battery voltage lower limit value, the battery 2 is charged by the power generation of the fuel cell 1. Therefore, the battery voltage can be recovered to the lower limit value or more. As a result, it is possible to suppress a decrease in the driving output of the forklift due to a shortage of battery voltage during the driving operation of the forklift.

  Further, when the electric power stored in the battery 2 is equal to or higher than the battery voltage lower limit value, when the operation amount of the cargo handling lever 6 and the accelerator pedal 9 is less than the specified amount, and it is determined that the battery 2 need not be charged, the fuel cell 1 Can be maintained in a stopped state, and the number of times the fuel cell 1 is repeatedly started and stopped can be reduced. Therefore, deterioration of the fuel cell 1 can be suppressed.

  Further, even when the electric power stored in the battery 2 is equal to or higher than the battery voltage lower limit value, it is necessary to charge the battery 2 when the operation amount of the cargo handling lever 6 and the accelerator pedal 9 is larger than the specified amount. Judgment is made and charging is started. Therefore, it is possible to suppress a drop in battery voltage, which is a drive voltage that can be supplied from the battery 2 for driving the forklift. As a result, it is possible to prevent the running of the forklift and the lifting operation of the fork from becoming unstable due to insufficient drive voltage.

Further, in an industrial vehicle, when performing an attachment operation for cargo handling (elevating and lowering operation of a fork, etc.) at the same time as traveling driving, the power consumption of the battery 2 is large and the battery voltage is likely to drop sharply as compared with the case where each is independently performed. Therefore, the operation tends to become unstable. However, in this embodiment, when the operation of the cargo handling lever 6 and the depression of the accelerator pedal 9 are performed at the same time, the fuel cell 1 is controlled so as to generate power regardless of the respective operation amounts. Therefore, it is possible to perform a stable operation while suppressing the battery voltage from dropping.
Further, since the electric power stored by the battery 2 is used as the driving force, the driving electric power can be supplied to the cargo handling motor 5 and the traveling motor 8 without time lag with respect to the operation of the forklift.

  The fuel cell operation control apparatus according to the present embodiment includes a means for detecting the amount of operation of the cargo handling lever 6 and a means for detecting the amount of depression of the accelerator pedal 9, but the amount of depression of the accelerator pedal 9 is detected. It is also possible to provide a simple configuration that does not include any means and includes only detection means for detecting the operation amount of the cargo handling lever 6. In this case, whether or not the fuel cell needs to be started can be determined based on only the detection result of the operation amount of the cargo handling lever 6 as in the present embodiment. In industrial vehicles, the power consumption due to the operation of the cargo handling attachment is particularly large. Therefore, by controlling the operation of the fuel cell based on the detection result of the operation operation amount, the start and stop of the fuel cell is suppressed, and the battery is It is possible to suppress a voltage drop.

  In addition, when the operation of the cargo handling lever 6 and the depression of the accelerator pedal 9 are performed at the same time, the fuel cell operation control apparatus according to the present embodiment performs power generation by the fuel cell 1 regardless of the operation amount. The amount of operation of the cargo handling lever 6 and the amount of depression of the accelerator pedal 9 are summed, and control is performed so that power generation by the fuel cell 1 is performed only when the sum is greater than or equal to a predetermined value. May be. Even when the operation of the cargo handling lever 6 and the depression of the accelerator pedal 9 are performed at the same time, the power consumption may be small with a small amount of operation or the amount of depression, so that unnecessary activation of the fuel cell 1 can be further suppressed. it can. The total value of the operation amount of the cargo handling lever 6 and the depression amount of the accelerator pedal 9 is a value obtained by adding the operation amounts actually operated by the operator, for example, the displacement amounts of the cargo handling lever 6 and the accelerator pedal 9 as they are. Not only the case but also the value obtained by converting the operation amount of the cargo handling lever 6 and the depression amount of the accelerator pedal 9 into a reference amount that can be added together (for example, multiplying by a predetermined coefficient, etc.) can be used.

(Second Embodiment)
FIG. 4 is a diagram showing a configuration of a control system using the fuel cell operation control apparatus according to the second embodiment of the present invention for a forklift. The second embodiment is further provided with necessary power calculation means 4 for calculating the power necessary for driving according to the operation amount from the detection results of the lever position sensor 7 and the accelerator opening sensor 10. And different. The same components as those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted. The required power calculation means 4 is constituted by a microcomputer or the like, for example, and can also be constituted by being incorporated in a microcomputer or the like constituting the power generation amount control means 3.

FIG. 5 shows a specific control flow by the fuel cell operation control apparatus according to the second embodiment. The control flow shown in FIG. 5 is executed when the cargo handling lever 6 or the accelerator pedal 9 is operated. It is also possible to set to execute at regular intervals.
In the present embodiment, the battery voltage lower limit value, the battery voltage upper limit value, and the specified power value P0 that is a criterion for determining whether to start power generation are determined in advance.

  First, the power generation amount control means 3 compares the battery voltage of the battery 2 with the battery voltage lower limit value (step S201). When the battery voltage is equal to or lower than the battery voltage lower limit value, power generation of the fuel cell 1 is performed until the battery voltage becomes equal to or higher than the upper limit value as in the first embodiment (steps S209, S210, and S211).

When the battery voltage of the battery 2 is equal to or higher than the battery voltage lower limit value, the accelerator depression amount is detected by the accelerator opening sensor 10 (step S202). Thereafter, the required power calculation means 4 calculates the power P1 consumed by the travel motor 8 based on the detection result by the accelerator opening sensor 10 (step S203). Further, the operation amount of the cargo handling lever 6 is detected by the lever position sensor 7 (step S204). Thereafter, the required power calculation means 4 calculates the power P2 consumed by the cargo handling motor 5 based on the detection result by the lever position sensor 10 (step S205). Further, the power consumption P3 of the auxiliary machine necessary for operating the fuel cell 1 such as a compressor, etc., that consumes power other than the traveling motor 8 and the cargo handling motor 5 is calculated (step S206).
These power consumptions (P1, P2, P3) are added to calculate the drive required power P required for driving according to the operation amount (step S207).

  Next, the power generation amount control means 3 compares the required drive power P calculated by the required power calculation means 4 with the specified power value P0. If the required drive power P is greater than or equal to the specified power value P0, the fuel cell 1 generates power (steps S208, S209, S210). The power generation by the fuel cell 1 is based on the calculated required driving power P, for example, the supply amount of hydrogen and the supply amount of air to the fuel cell 1 are controlled so that the generated power amount by the fuel cell 1 becomes the required driving power P. Is done. As in the first embodiment, it is also possible to calculate the fuel cell output so that the target voltage during driving is determined in advance and the battery voltage follows the target voltage.

  Further, when the required driving power P is smaller than the specified power value P0, the power consumption by the forklift lifting / lowering operation and the traveling drive is small, and it is determined that power generation by the fuel cell 1 is unnecessary, and the fuel cell 1 is maintained in a stopped state. (Steps S208 and S200).

  By controlling the operation of the fuel cell 1 in this way, when the battery voltage of the battery 2 is equal to or higher than the battery voltage lower limit value, the forklift according to the operation amount of the cargo handling lever 6 and the accelerator pedal 9 is calculated by the required power calculation means 4. Since the required drive power required for driving the vehicle is calculated, the necessity of starting the fuel cell and the required power generation amount of the fuel cell can be determined at the same time based on the calculation result, and the control is performed efficiently. Can be done.

(Third embodiment)
FIG. 6 is a diagram showing a configuration of a control system using a fuel cell operation control apparatus according to a third embodiment of the present invention for a forklift. The third embodiment differs from the second embodiment in that it further includes a load sensor 12 (loading load detection means) that detects the load (loading load) of the load 11 loaded on the fork. The same components as those of the second embodiment are denoted by the same reference numerals, and description thereof is omitted.
As the load sensor 12, for example, a hydraulic meter that measures the hydraulic pressure of a lift cylinder that moves the fork up and down, a load cell that is attached so that the load of the load is directly loaded, and the like can be used.

FIG. 7 shows a specific control flow by the fuel cell operation control apparatus according to the third embodiment. Note that the control flow shown in FIG. 7 is executed when the cargo handling lever 6 or the accelerator pedal 9 is operated. It is also possible to set to execute at regular intervals.
In the present embodiment, similarly to the second embodiment, a battery voltage lower limit value, a battery voltage upper limit value, and a specified power value P0 that is a criterion for determining whether to start power generation are determined in advance. deep.

  First, the power generation amount control means 3 compares the battery voltage of the battery 2 with the battery voltage lower limit value (step S301). When the battery voltage is equal to or lower than the battery voltage lower limit value, power generation of the fuel cell 1 is performed until the battery voltage becomes equal to or higher than the upper limit value as in the first embodiment (steps S310, S311, and S312).

  When the battery voltage of the battery 2 is equal to or higher than the battery voltage lower limit value, the load handling load is detected by the load sensor 12 (step S302). Further, the accelerator depression amount is detected by the accelerator opening sensor 10 (step S303). Thereafter, the required power calculation means 4 calculates the power P1 ′ (travel power) consumed by the travel motor 8 based on the detection result by the load sensor 12 and the detection result by the accelerator opening sensor 10 (step S304). . This calculation can be performed using a calculation formula prepared in advance so that the power consumption of the travel motor 8 can be calculated using the detected cargo handling load and accelerator opening as parameters. As a result, the electric power required for driving the traveling motor 8 that can vary as the cargo handling load changes can be calculated with higher accuracy.

  Further, the operation amount of the cargo handling lever 6 is detected by the lever position sensor 7 (step S305). Thereafter, the required power calculation means 4 calculates the power P2 '(loading power) consumed by the cargo handling motor 5 based on the detection result by the load sensor 12 and the detection result by the lever position sensor 10 (step S306). This calculation can be performed using a formula that has been created in advance so that the power consumption of the cargo handling motor 8 can be calculated using the cargo handling load and the operation amount of the cargo handling lever 6 as parameters. As a result, the electric power required for driving the cargo handling motor 5 that can vary as the cargo handling load changes can be calculated more accurately.

Further, the required power calculation means 4 calculates the power consumption P3 of the auxiliary machine (step S307). When the influence of the cargo handling load is also large, the power consumption P3 of the auxiliary machine can be calculated with correction using the cargo handling load detected by the load sensor 12.
The required power calculation means 4 adds these power consumptions (P1 ′, P2 ′, P3) to calculate the drive required power P required for driving according to the operation amount (step S308). .

  Next, the power generation amount control means 3 compares the required drive power P calculated by the required power calculation means 4 with the specified power value P0, and the required drive power P calculated by the required power calculation means 4 is the specified power value. When it is P0 or more, power generation is performed by the fuel cell 1 (steps S309, S310, and S311). Further, when the required driving power P is smaller than the specified power value P0, the fuel cell 1 is maintained in a stopped state (steps S309 and S300).

  By controlling the operation of the fuel cell 1 in this way, the required driving power P is calculated in consideration of the cargo handling load applied to the forklift, and thus is calculated as compared with the case of calculating without considering the cargo handling load. The required drive power P can be made closer to the power actually consumed, and the required drive power P can be calculated with high accuracy. Therefore, unnecessary activation of the fuel cell 1 can be further suppressed.

  Further, since it is possible to easily determine whether or not the fuel cell 1 needs to be started by comparing the required driving power P and the specified power P0, the control mechanism of the power generation amount control means 3 can be simplified. . In addition, it can be easily manufactured.

  Note that, as shown in the present embodiment, the required drive power P calculated by the required power calculation means 4 is compared with a predetermined specified power P0 to determine whether or not the fuel cell 1 needs to be started. Alternatively, it is possible to determine the required power Pt based on the battery voltage of the battery 2 at the time of determination and compare the specified power Pt with the required drive power P to determine whether the fuel cell 1 needs to be activated. .

By controlling the operation of the fuel cell 1 in this way, the necessity of starting the fuel cell 1 is determined in consideration of the state of charge of the battery 2 when the necessity of starting the fuel cell 1 is determined. be able to. For example, when the battery voltage at the time of determination is sufficiently larger than the battery voltage lower limit value, the specified power Pt is set to automatically increase corresponding to the battery voltage, and the drive calculated based on the operation amount Even when the required power P is large, the fuel cell 1 can be controlled to be maintained in the stopped state if it is equal to or less than the specified power Pt. Conversely, if the battery voltage at the time of determination is greater than or equal to the battery voltage lower limit, but the difference is small, the specified power Pt is set to be small corresponding to the battery voltage, and even if the operation amount is small It is also possible to perform control so that the fuel cell 1 is started to start power generation. As a result, it is possible to suppress a decrease in battery voltage that makes the driving of the forklift unstable, and to suppress unnecessary activation of the fuel cell.
It is also possible to charge the battery 2 by controlling the amount of power generated by the fuel cell 1 based on the specified power Pt and the drive required power P determined as described above. For example, when the calculated required driving power P is significantly larger than the specified power Pt, it is possible to control the power generation amount by the fuel cell 1 to be larger.

The embodiments of the present invention have been described above. However, the present invention is not limited to the above-described embodiments, and various modifications can be made as long as they are described in the claims.
For example, the present invention can also be used when operating a motor used to operate a hydraulic device such as a mast tilting operation in a forklift or a tire steering operation by power steering.
Further, the present invention can be used not only for forklifts but also for industrial vehicles used for agriculture, civil engineering construction, cargo transportation and the like that require operation of a cargo handling attachment.

It is a figure which shows the structure of the operation control apparatus of the fuel cell which concerns on 1st Embodiment of this invention. It is a figure which shows the control flow by the operation control apparatus of the fuel cell which concerns on 1st Embodiment. FIG. 3 is a diagram showing temporal changes in the handling lever operation amount (a), the forklift drive output (b), the battery voltage (c), and the operating state (d) of the fuel cell. It is a figure which shows the structure of the operation control apparatus of the fuel cell which concerns on 2nd Embodiment of this invention. It is a figure which shows the control flow by the operation control apparatus of the fuel cell which concerns on 2nd Embodiment. It is a figure which shows the structure of the operation control apparatus of the fuel cell which concerns on 3rd Embodiment of this invention. It is a figure which shows the control flow by the operation control apparatus of the fuel cell which concerns on 3rd Embodiment.

Explanation of symbols

1 Fuel cell 2 Battery (electric storage means)
3 Power generation amount control means 4 Required power calculation means 5 Cargo handling motor 6 Cargo handling lever (first operation means)
7 Lever position sensor (first operation amount detection means)
8 Traveling motor 9 Accelerator pedal (second operating means)
10 Accelerator opening sensor (second operation amount detection means)
11 Luggage 12 Load sensor (loading load detection means)
S101 Power generation amount control means S102 First operation amount detection means, second operation amount detection means S103, S104, S105 Power generation amount control means S106 Power generation amount control means S107, S108 Power generation amount control means, fuel cells S201, S208, S209, S211 Power generation amount control means S202 Second operation amount detection means S203, S205, S206, S207 Required power calculation means S204 First operation amount detection means S210 Power generation amount control means, fuel cells S301, S309, S310, S312 Power generation amount control means S302 Cargo handling Load detection means S303 Second operation amount detection means S304, S306, S307, S308 Required power calculation means S305 First operation amount detection means S311 Power generation amount control means, fuel cell

Claims (9)

A fuel cell operation control device in an industrial vehicle driven by electric power generated using a fuel cell,
Power storage means for storing electric power generated using the fuel cell;
A power generation amount control means for controlling the power generation amount of the fuel cell;
First operation amount detection means for detecting an operation amount of the first operation means capable of controlling the operation of the cargo handling attachment of the industrial vehicle according to the operation amount;
With
The power generation amount control means controls the power generation amount of the fuel cell to charge the power storage means when the electric power stored in the power storage means is smaller than a predetermined value, and stores the power in the power storage means. When the generated electric power is greater than or equal to the predetermined value, the power storage unit can be charged by controlling the amount of power generated by the fuel cell based on the detection result by the first operation amount detection unit. Battery operation control device. A second operation amount detecting means for detecting an operation amount of the second operation means capable of controlling the traveling speed of the industrial vehicle according to the operation amount;
When the electric power stored in the power storage means is greater than or equal to the predetermined value, the power generation amount control means is based on a detection result by the first operation amount detection means and the second operation amount detection means. 2. The fuel cell operation control device according to claim 1, wherein the power storage means can be charged by controlling the amount of power generated by the fuel cell.   The power generation amount control means, when the power stored in the power storage means is greater than or equal to the predetermined value, when the operation amount of the first operation means is greater than or equal to a predetermined first prescribed operation amount, or Only when the operation amount of the second operation means is greater than or equal to a predetermined second prescribed operation amount, or when the second operation means and the first operation means are operated simultaneously, the fuel cell 3. The fuel cell operation control device according to claim 2, wherein the power storage unit is charged by controlling the amount of power generation.   When the second operating means and the first operating means are operated at the same time, only when the total value of the operating amount of the first operating means and the operating amount of the second operating means is a predetermined value or more. 4. The fuel cell operation control device according to claim 3, wherein the amount of power generated by the fuel cell is controlled to charge the power storage means. Further comprising required power calculation means for calculating required drive power, which is power required for driving the industrial vehicle, based on detection results by the first operation amount detection means and the second operation amount detection means;
The power generation amount control means controls the power generation amount by the fuel cell based on the required drive power calculated by the required power calculation means when the power stored in the power storage means is greater than or equal to the predetermined value. 3. The fuel cell operation control device according to claim 2, wherein the power storage means can be charged. It further comprises a cargo handling load detecting means for detecting the cargo handling load of the industrial vehicle,
The required power calculation means calculates cargo handling power, which is power required for the operation of the cargo handling attachment of the industrial vehicle, from the detection results of the first operation amount detection means and the cargo handling load detection means, and the second operation Calculating travel power, which is power necessary for traveling the industrial vehicle, from the detection results by the quantity detection means and the load handling load detection means, and calculating the drive power requirement based on the load handling power and the travel power. The fuel cell operation control device according to claim 5.   The power generation amount control means, when the power stored in the power storage means is greater than or equal to the predetermined value, when the required drive power calculated by the required power calculation means is greater than a predetermined specified power, 7. The fuel cell operation control apparatus according to claim 5, wherein the power storage unit is charged by controlling the amount of power generated by the fuel cell based on the required driving power.   The power generation amount control means determines the required drive power calculated by the required power calculation means based on the power stored in the power storage means when the power stored in the power storage means is greater than or equal to the predetermined value. The power storage means is charged by controlling the amount of power generated by the fuel cell based on the required driving power and the power stored in the power storage means when the power is larger than the prescribed power to be stored. A fuel cell operation control device according to claim 5 or 6. An operation control device for the fuel cell in a forklift that travels and raises and lowers the fork with electric power generated using the fuel cell,
The said 1st operation amount detection means is a detection means which detects the operation amount of the cargo handling lever for raising / lowering the fork of the said forklift, The said any one of Claim 1 thru | or 8 characterized by the above-mentioned. Fuel cell operation control device.

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