JP2010279124A - Moving body - Google Patents

Abstract

An object of the present invention is to achieve efficient driving in accordance with a user's intended use in a moving body that uses a fuel cell and a secondary battery separately.
A fuel cell (2), a secondary battery (4) that can be charged from an external power source, a fuel cell (2) and / or a motor (8) using the secondary battery (4) as a drive source, And a control unit (9) for controlling the drive source, wherein the control unit (9) uses the fuel cell (2) as a main drive source and the secondary battery (4) as a sub-carrier. FCHV driving mode with the secondary battery (4) as the main driving source and the fuel cell (2) as the sub driving source, and only the secondary battery (4) as the driving source A moving body (1) that switches the EV running mode to be switched based on a user command is provided.
[Selection] Figure 1

Description

  The present invention relates to a mobile body, in particular, a mobile body equipped with a fuel cell and a secondary battery that can be charged from the outside.

  A hybrid vehicle that has two or more drive sources with different operating principles and that travels by selecting one or more drive sources from these power sources according to the situation of the vehicle has been put into practical use. In particular, in recent years, a hybrid vehicle using a fuel cell and a secondary battery has attracted attention as a drive source with a small environmental load.

  As such a hybrid vehicle, for example, in Patent Document 1, in a hybrid vehicle that moves using a motor generator that uses a fuel cell and a power source as a power source and a heat engine as a drive source, these drive sources are based on predetermined switching conditions. It has been proposed to realize efficient driving by using different types.

JP 2002-10409 A

  However, in the conventional hybrid vehicle as described above, since the drive source is selected based on a certain control instant (switching condition), the fuel gas is used up in an area where there is no fuel cell fuel gas station. Even if there is an opportunity to charge, fuel gas with a high energy cost may be used without using a secondary battery.

  In other words, the diversity of drive sources improves energy conservation and robustness as a moving body, but in actual use, optimal energy consumption and replenishment are performed according to the maintenance status of the replenishment base of each drive source. Without the benefits, the existing hybrid control system cannot accurately predict and read the user's intention, and the optimal drive source is selected according to the user's intended use. I couldn't.

  Accordingly, the present invention has been made in view of the above-described problems of the prior art, and realizes an efficient operation in accordance with a user's intended use in a moving body that uses a fuel cell and a secondary battery separately. For the purpose.

  In the present invention, the following means are adopted in order to solve the above-mentioned problems. That is, a mobile body including a fuel cell, a secondary battery that can be charged from an external power source, a motor that uses the fuel cell and / or the secondary battery as a drive source, and a control unit that controls the drive source. The control unit includes an FCHV traveling mode in which the fuel cell is a main driving source and the secondary battery is a sub driving source, and the fuel cell is a sub driving source that uses the secondary battery as a main driving source. Provided is a moving body that switches between an FCEV travel mode using a drive source and an EV travel mode using only the secondary battery as a drive source based on a user command.

  In the FCHV traveling mode, the FCEV traveling mode, and the EV traveling mode, the consumption of the fuel gas (for example, hydrogen gas) of the fuel cell decreases in this order, and conversely, the consumption of the electric power accumulated in the secondary battery increases. . According to the said structure, these three driving modes can be selected by a user's selection. In other words, according to the user's selection, the driving mode that uses the fuel gas as much as possible, the driving mode that uses the power of the secondary battery as much as possible while suppressing the consumption of the fuel gas, and the mode that uses only the power of the secondary battery can be separated. it can. As a result, driving that accurately reflects the user's drive energy consumption / supply intention according to the distance to the supply base of the drive source, the cruising schedule, and the like becomes possible. For example, if the fuel gas is exhausted in an area where there is no fuel gas station for the fuel cell, or there is an opportunity to charge the secondary battery, do not use the secondary battery (reserve the power of the secondary battery). It is possible to prevent the use of fuel gas with high energy costs.

  In the above configuration, in the FCHV traveling mode, power generated by the fuel cell is preferentially used, and the power of the secondary battery is maintained at a target value where the remaining charge of the secondary battery is constant. You may make it use only within the range to sag.

  According to the above configuration, in the FCHV traveling mode, the secondary battery is not used when the remaining charge of the secondary battery falls below a certain target value. In other words, the use of the secondary battery is centered on the use of regenerative power collected at the time of deceleration or the like. Thereby, it becomes possible for a user to drive | run by maintaining the charge remaining amount of a secondary battery more than a fixed target value by selecting FCHV driving mode.

  In the above configuration, in the FCEV traveling mode, the power of the secondary battery is preferentially used, and the power generated by the fuel cell is used only when the power of the secondary battery is insufficient. You may do it.

  According to the above configuration, in the FCEV traveling mode, the fuel gas of the fuel cell is consumed only when the power of the secondary battery is insufficient. As a result, the user can select the FCEV travel mode, and travel while suppressing the fuel gas consumption of the fuel cell as much as possible while obtaining a desired output.

  Further, in the above configuration, the control unit is configured such that the remaining charge amount of the secondary battery reaches a lower limit of a normal use region and the remaining fuel gas amount of the fuel cell during traveling in the FCEV traveling mode or the EV traveling mode. May be automatically switched from the travel mode to the FCHV travel mode.

  According to the above configuration, when the fuel gas remains above a predetermined value, when the remaining charge of the secondary battery decreases, the fuel cell is automatically switched to a travel mode that preferentially consumes fuel. It can be prevented that the remaining charge exceeds the normal use area.

  The “lower limit of the normal use area” is a value set based on a limit value of the remaining charge level that does not cause deterioration of the secondary battery, and is set by adding a predetermined margin to the limit value. Is preferred.

  Further, in the above configuration, the control unit is configured such that the remaining charge amount of the secondary battery reaches a lower limit of a normal use region and the remaining fuel gas amount of the fuel cell during traveling in the FCEV traveling mode or the EV traveling mode. Is less than a predetermined value, the output of the motor is limited, and the mode may be automatically switched to the EV evacuation travel mode using only the secondary battery as a drive source.

  According to the above configuration, when the fuel gas and the remaining charge of the secondary battery are less than a predetermined value, the output of the motor is automatically limited and the mode is switched to the EV evacuation running mode in which only the secondary battery runs. It is possible to prevent a situation where the energy source suddenly stops and the traveling stops, and a cruising distance to a drive source supply base or a safe evacuation site can be secured. Note that, at low loads where the output of the motor is limited, the secondary battery has higher fuel efficiency, so that it is possible to travel more efficiently than when retreating with the fuel cell.

  In the above configuration, when warming up using the external power source, if the travel mode is the EV travel mode, only the secondary battery is warmed up, and the travel mode is the FCEV travel mode or the FCHV travel. In some cases, both the secondary battery and the fuel cell may be warmed up.

  According to the above configuration, when the fuel cell is not used immediately, the fuel cell is not warmed up, so that power consumption during warming can be minimized.

  Moreover, in the said structure, you may make it provide the notification means which notifies a user the cruising range according to driving | running | working modes.

  According to the above configuration, since the user can know in advance how much the vehicle can move according to the travel mode, it is possible to prevent the user from selecting a travel mode that causes a fuel shortage in advance.

  In the present invention, the notification means widely includes means for transmitting information by acting on the user's five senses, such as displaying information on a display or reading out information by voice.

  ADVANTAGE OF THE INVENTION According to this invention, in the mobile body which drives a fuel cell and a secondary battery separately, it can implement | achieve the efficient driving | operation along a user's intended use.

The schematic diagram which shows the structure of a plug-in hybrid vehicle. (A) is a schematic diagram showing an example of SOC control in the FCHV traveling mode. (B) is a schematic diagram showing an example of SOC control in the FCEV travel mode. The schematic diagram which shows the example of a display on the display of each driving mode. Transition diagram of travel mode automatic switching.

  Hereinafter, a mobile object according to an embodiment of the present invention will be described with reference to the drawings. In the drawings, the same parts are denoted by the same reference numerals. In this embodiment, a plug-in hybrid vehicle including a fuel cell and a secondary battery will be described as an example. Of course, the moving body is not limited to a vehicle, and may be, for example, a robot, a ship, an aircraft, or the like.

(overall structure)
FIG. 1 is a schematic diagram showing a configuration of a plug-in hybrid vehicle 1 according to an embodiment of the present invention. A plug-in hybrid vehicle 1 (hereinafter also simply referred to as “vehicle 1”) shown in FIG. 1 includes a fuel cell 2, an FC converter 3, a battery 4, an external power connection terminal 5, a battery converter 6, and an inverter. 7, a trunk motor 8, a control unit 9, and the like.

  The fuel cell 2 is formed of a solid polymer electrolyte type, for example, and has a stack structure in which a large number of single cells are stacked. Each single cell has a membrane / electrode assembly (hereinafter also referred to as “MEA”) and a pair of separators arranged so as to sandwich the MEA from both sides. Specifically, each MEA includes a polymer electrolyte membrane and a pair of catalyst layers arranged so as to sandwich the polymer electrolyte membrane from both sides. The pair of catalyst layers function as an anode and a cathode, and an electrode reaction is performed at the interface between the catalyst layer and the electrolyte membrane.

  The fuel cell 2 is provided with a fuel gas supply system that supplies fuel gas to the anode of each single cell, and an oxidant gas supply system that supplies oxidant gas to the cathode of each single cell (all not shown). The fuel gas and the oxidizing gas are supplied to each unit cell of the fuel cell in response to a control signal from the control unit 9. Here, the fuel gas means hydrogen gas containing hydrogen. The oxidizing gas means a gas containing an oxidizing agent typified by oxygen or air. The fuel cell 2 generates electric power by the electrochemical reaction of the supplied fuel gas and oxidizing gas.

FC converter 3 is a DC-DC converter of the DC, secondary to the primary side converted into different voltage values V _out and the voltage V _in input to the (fuel cell 2 side) primary (increased or decreased) Output to the inverter (inverter 7 side). The converter 3 boosts / steps down the output voltage of the fuel cell 2 to a target output in accordance with a control signal from the control unit 9.

  The battery 4 is connected in parallel with the fuel cell 2 with respect to the trunk motor 8, and for example, a large-capacity secondary battery such as a lithium ion battery or a nickel metal hydride battery is used. The battery 4 can be charged from the outside (for example, a household outlet) via the external power connection terminal 5, and can be used, for example, by charging the battery 4 with cheap night power before traveling. is there.

  The battery 4 also functions as a regenerative power storage source during braking. When the vehicle 1 is decelerated, the trunk motor 8 functions as a generator, and the battery 4 stores regenerative power at that time. The amount of charge (SOC: State of Charge) of the battery 4 increases due to charging from the external power supply connection terminal 5 or regenerative power from the traction motor 8, and decreases due to output to the traction motor 8. The battery 4 has an upper limit and a lower limit of the SOC to prevent deterioration, and normally charging and discharging are repeated between the upper limit and the lower limit (normal use region). The lower limit of the SOC is set by adding a predetermined buffer (electric power necessary for traveling in an EV evacuation traveling mode to be described later) to a limit value at which deterioration occurs.

  The battery converter 6 boosts / steps down the discharge voltage supplied from the battery 4 to the required voltage under the control of the control unit 9. Further, the battery converter 6 boosts / steps down the DC voltage input from the trunk motor via the inverter 7 and outputs the boosted voltage to the battery 4. By such a function of the battery converter 6, charging / discharging of the battery 4 is realized.

  The inverter 7 converts a direct current into a three-phase alternating current and supplies it to the traction motor 8. The trunk motor 8 is, for example, a three-phase AC motor. The trunk motor 8 constitutes a main power source of the vehicle 1 and is connected to the wheels 10L and 10R of the vehicle 1. As described above, the trunk motor 8 functions as a generator when the vehicle 1 is decelerated, converts kinetic energy obtained during braking into electrical energy, and outputs regenerative power at that time to the battery 4.

  The control unit 9 detects an operation amount of an acceleration operation member (for example, an accelerator) provided in the vehicle 1, and controls information such as an acceleration request value (for example, a required power generation amount from a power consuming device such as the traction motor 8). In response, the operation of various devices in the system is controlled. In addition to the traction motor 8, the power consuming device includes, for example, auxiliary equipment (for example, a compressor and a hydrogen pump motor) necessary for operating the fuel cell 2, and various devices (for example, motors of a compressor and a hydrogen pump) Actuators used in transmissions, wheel control devices, steering devices, suspension devices, etc.), passenger space air conditioners (air conditioners), lighting, audio, and the like.

  The control unit 9 physically includes, for example, a CPU, a ROM that stores a control program and control data processed by the CPU, a RAM mainly used as various work areas for control processing, and an input / output Interface. These elements are connected to each other via a bus. A user interface such as a display and a switch and various sensors such as a voltage sensor, a current sensor, and a pressure sensor are connected to the input / output interface, and various drivers for driving the traction motor 8 and the like are connected to the input / output interface.

(Manual switching of driving mode)
The control unit 9 receives a user command via a user interface provided in the vehicle 1 and controls driving of the fuel cell 2 and the battery 4. Hereinafter, the switching control of the traveling mode of the vehicle 1 by the control unit 9 will be described in detail with reference to FIGS. 2A is a schematic diagram illustrating an example of SOC control in the FCHV traveling mode, FIG. 2B is a schematic diagram illustrating an example of SOC control in the FCEV traveling mode, and FIG. 3 is a display on the display of each traveling mode. It is a schematic diagram which shows the example of a display.

In the present embodiment, the control unit 9 switches the following three travel modes in which the usage ratios of the fuel cell 2 and the battery 4 are different according to a command from the user.
1. FCHV driving mode 2. FCEV travel mode EV driving mode

  The FCHV traveling mode is a traveling mode in which the fuel cell 2 is a main drive source of the trunk motor 8 and the battery 4 is a sub drive source. In the FCHV traveling mode, the power generated by the fuel cell 2 is preferentially used, and the power stored in the battery 4 is used only within a range where the SOC of the battery 4 is maintained at a constant target value. More specifically, as shown in FIG. 2A, in the FCHV traveling mode, the control unit 9 controls the battery 4 so as to keep the target SOC of the battery 4 at a constant target value in the normal use region. Control the output of. Since the SOC of the battery 4 increases due to the regenerative power, in other words, the use of the battery 4 in the present travel mode is mainly based on the use of the regenerative power collected during deceleration. The fuel cell 2 occupies a large weight as a drive source for the traction motor 8.

  In other words, the FCHV traveling mode is a traveling mode in which the SOC of the battery 4 is not reduced during traveling and mainly consumes hydrogen gas from the fuel cell, and is typically suitable for long-distance traveling.

  On the other hand, the FCEV travel mode is a travel mode in which the battery 4 is a main drive source of the trunk motor 8 and the fuel cell 2 is a sub drive source. In the FCEV travel mode, the fuel gas of the fuel cell 2 is consumed only when the power of the battery 4 is insufficient. More specifically, as shown in FIG. 2B, the control unit 9 gradually decreases the target SOC of the battery 4 based on the average required power from the trunk motor 8 in the FCEV travel mode. As a result, the power stored in the battery 4 is preferentially used, and the generated power of the fuel cell 2 is used only when the trunk motor 8 is requested to exceed the average required power, such as sudden acceleration or a slope. Will be used.

  In the FCEV traveling mode, the power of the battery 4 with low energy cost can be preferentially used and the assist power from the fuel cell 2 can be received, so that the traveling performance is not limited. As long as there is a margin in power, the travel mode is preferable.

  The EV travel mode is a travel mode in which only the battery 4 is used as a drive source for the trunk motor 8. In the EV travel mode, the fuel cell 2 is not in operation. There is an advantage that the total energy cost can be kept low because only the power of the cheap battery 4 is used and no expensive hydrogen gas is used.

  However, in the EV travel mode, since the vehicle travels only with the electric power of the battery 4, the cruising distance, travel performance (acceleration force, maximum speed), and the like are limited. Therefore, the EV traveling mode is suitable for traveling in a short distance or traveling in an area where there is no problem even if the traveling performance is limited in an urban area. In addition, the fuel cell 2 has an optimum operating temperature, and if the fuel cell 2 does not warm up to a certain temperature (for example, 40 degrees to 80 degrees), the power generation efficiency is lowered. Therefore, the temperature of the fuel cell 2 is increased. Even in such a situation that the fuel cell is stopped immediately (typically, short distance movement), the EV traveling mode is suitable.

  In the FCHV traveling mode, the FCEV traveling mode, and the EV traveling mode, the consumption amount of hydrogen gas in the fuel cell 2 decreases in this order, and the consumption amount of power stored in the battery 4 increases. In the present embodiment, these three travel modes can be selected by the user's selection. In other words, according to the user's selection, it is possible to distinguish between a travel mode that uses fuel gas as much as possible, a travel mode that uses the power of the battery 4 as much as possible while suppressing consumption of the fuel gas, and a mode that uses only the power of the battery 4. As a result, driving that accurately reflects the user's drive energy consumption / supply intention according to the distance to the supply base of the drive source, the cruising schedule, and the like becomes possible. For example, the fuel gas is exhausted in an area where there is no fuel gas station for the fuel cell, or even though there is an opportunity to charge the battery 4, expensive hydrogen gas is used without using the battery 4. Can be prevented.

  For example, as shown in FIG. 3, the travel mode is selected by displaying the travel mode selection screens 11 </ b> A to 11 </ b> C together with the cruising distance in each travel mode on the touch panel display 11 provided in the vehicle 1. You may do it. Further, as shown in FIG. 3, guidance for the shortest distance to the hydrogen gas station and the charging station may be performed along with the cruising range. Accordingly, since the user can grasp in advance the cruising distance and the fuel supply station in each traveling mode, it is possible to prevent the selection of the traveling mode that causes the fuel to run out in advance.

  The travel mode can be selected by operating a mechanical switch, a remote control button, or the like, or by voice input. In addition, notification to the cruising range and fuel station in each travel mode may be made by voice or the like.

(Automatic switching of driving mode)
When the SOC of the battery 4 reaches the lower limit of the normal use area while the vehicle 1 is driven in each travel mode according to the user selection, the control unit 9 automatically switches to the travel mode in which the battery 4 consumes less power. Switch to. This will be described with reference to FIG. Here, FIG. 4 is a transition diagram of the automatic switching of the running mode.

  As shown in FIG. 4, when the SOC reaches the lower limit of the normal use region in the EV traveling mode or the FCEV traveling mode, the control unit 9 detects the remaining amount of hydrogen gas, and when there is hydrogen gas, the FCHV traveling mode is detected. And automatically notifies the user of the switching by voice or the like. As described above, in the FCHV traveling mode, the use of regenerative power is the center, and the SOC of the battery 4 is maintained at a constant value (here, the lower limit value of the normal use region), so that the stored amount of the battery 4 is not further reduced. It will be possible to travel. As a result of continuing running in this state, the control unit 9 performs the EV evacuation running mode when the hydrogen gas runs out or when the SOC reaches the lower limit and the hydrogen gas runs out in the EV running mode and the FCEV running mode. Switch to automatically.

  The EV evacuation travel mode is an emergency evacuation travel mode. In this travel mode, the control unit 9 consumes the power of the battery 4 to a limit value at which the battery 4 does not deteriorate (that is, consumes the buffer power from the lower limit of the SOC to the limit value). The vehicle 1 can be moved to the nearest hydrogen gas / charging station, parking area or the like while suppressing the running performance of the vehicle as much as possible.

  As described above, when the hydrogen gas and the remaining amount of the battery 4 are reduced, the output of the traction motor 8 is automatically limited to switch to the EV evacuation traveling mode in which only the battery 4 travels, thus preventing a situation where the traveling suddenly stops. It is possible to secure a cruising distance to a safe place for receiving a refueling station of a driving source and refueling. Note that, when the load is low, the battery 4 has higher fuel efficiency, and therefore, it is possible to travel more efficiently than when the fuel cell 2 performs retreat travel.

(Switching warm-up mode)
For example, when the vehicle 1 is stopped in a garage or the like, an external power supply is connected to the battery 4 via the external power supply connection terminal 5. At this time, the control unit 9 warms up the vehicle 1 using an external power source based on a user's operation or a warm-up command from a timer or the like.

  When there is a warm-up command, the control unit 9 switches the warm-up target according to the travel mode selected at that time (or highly likely to be selected at the start of travel). Specifically, when traveling in the EV traveling mode is started, only the battery 4 is warmed up, and the fuel cell 2 is not warmed up. On the other hand, when traveling in the FCEV traveling mode and the FCHV traveling mode is started, the fuel cell 2 is warmed up in addition to the battery 4. When the fuel cell 2 is not used immediately, the fuel cell 2 is not warmed up, so that power consumption during warm-up can be minimized.

  Although the embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and it goes without saying that various embodiments can be implemented without departing from the scope of the present invention. Absent.

DESCRIPTION OF SYMBOLS 1 ... Plug-in hybrid vehicle, 2 ... Fuel cell, 3 ... FC converter, 4 ... Battery (secondary battery), 5 ... External power supply connection terminal, 6 ... Battery converter, 7 ... Inverter, 8 …… Traction motor, 9 …… Control unit, 10L, 10R …… Wheel, 11 …… Display, 11A to 11C …… Driving mode selection screen

Claims (7)

A fuel cell;
A secondary battery that can be charged from an external power source;
A motor using the fuel cell and / or the secondary battery as a drive source;
A control unit that controls the drive source,
The controller includes an FCHV traveling mode in which the fuel cell is a main drive source and the secondary battery is a sub drive source, and the fuel cell is a sub drive source using the secondary battery as a main drive source. A moving body that switches between an FCEV travel mode and an EV travel mode using only the secondary battery as a drive source based on a user command.   In the FCHV driving mode, power generated by the fuel cell is preferentially used, and the power of the secondary battery is only within a range in which the remaining charge of the secondary battery is maintained at a constant target value. The moving body according to claim 1 used.   The power of the secondary battery is preferentially used in the FCEV traveling mode, and the power generated by the fuel cell is used only when the power of the secondary battery is insufficient. The moving body according to 2.   When the controller is in the FCEV traveling mode or the EV traveling mode, the remaining charge of the secondary battery reaches a lower limit of a normal use range, and the remaining fuel gas of the fuel cell is equal to or greater than a predetermined value. The mobile body according to claim 1, wherein the traveling mode is automatically switched to the FCHV traveling mode.   The control unit is configured such that the remaining charge level of the secondary battery reaches a lower limit of a normal use range during traveling in the FCEV travel mode or the EV travel mode, and the fuel gas remaining amount of the fuel cell is less than a predetermined value. 5. The moving body according to claim 1, wherein the output of the motor is limited and the mode is automatically switched to an EV evacuation traveling mode in which only the secondary battery is used as a driving source.   When warming up using the external power source, when the travel mode is the EV travel mode, only the secondary battery is warmed up, and when the travel mode is the FCEV travel mode or the FCHV travel, the secondary battery is warmed up. The moving body according to claim 1, wherein both the battery and the fuel cell are warmed up.   The mobile body according to claim 1, further comprising a notification unit that notifies a user of a cruising distance according to a travel mode.

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