JP4437103B2 - Vehicle start control method - Google Patents

Description

  The present invention relates to a vehicle start control method.

  Conventionally, for example, a polymer electrolyte fuel cell is a stack formed by laminating a plurality of cells to a cell formed by sandwiching a polymer electrolyte membrane between a fuel electrode and an oxygen electrode from both sides (hereinafter referred to as a stack). (Referred to as a fuel cell), hydrogen is supplied to the fuel electrode as fuel, air is supplied to the oxygen electrode as oxidant, and hydrogen ions generated by a catalytic reaction at the fuel electrode are converted into a solid polymer electrolyte membrane. It passes through to the oxygen electrode and generates electricity by causing an electrochemical reaction with oxygen at the oxygen electrode.

In a vehicle equipped with such a fuel cell such as a polymer electrolyte membrane fuel cell, conventionally, for example, as in the fuel cell vehicle disclosed in Patent Document 1 and its starting method, the vehicle is started and the fuel cell is started. Prior to this, a technique for performing a safety inquiry, for example, detecting that hydrogen supplied to the fuel electrode side of the fuel cell is not leaking is known.
Here, as a hydrogen sensor for detecting hydrogen, for example, a gas detection element made of a catalyst such as platinum and a temperature compensation element are provided, and gas detection is performed by heat generated by combustion when hydrogen contacts the catalyst such as platinum. A gas that detects the concentration of hydrogen according to the difference in electrical resistance generated between the element and a temperature compensation element in a relatively low temperature state, such as at ambient temperature, when the element is in a relatively high temperature state. A catalytic combustion type hydrogen sensor is known.
JP-A-7-170613

By the way, in the fuel cell vehicle according to an example of the above-described prior art, the detection by the hydrogen sensor is started after the operation for starting the stopped vehicle, for example, the opening of the vehicle door or the like is executed. Yes. However, when the driver of the vehicle opens the vehicle door and gets into the vehicle, for example, when the switch for shifting the vehicle to a travelable state, such as an ignition switch, is turned on, detection by the hydrogen sensor, and this If the safety confirmation process or the like based on the detection result is not completed, for example, the start of the fuel cell startup process or the like is delayed, which causes a problem that it is difficult to start the vehicle quickly. For this reason, at the time of starting the vehicle, it is desirable to start detection by a hydrogen sensor and safety confirmation processing based on the detection result earlier.
However, if the hydrogen concentration is detected using a conventional gas catalytic combustion type hydrogen sensor, it is necessary to perform a heat treatment up to a predetermined temperature in order to exert the action of the catalyst provided in the hydrogen sensor. As the time required for this increases, the power consumed by the hydrogen sensor increases, resulting in an obstacle to improving fuel consumption.

  The present invention has been made in view of the above circumstances, and provides a vehicle start control method capable of quickly starting a vehicle even when a vehicle state is inspected prior to starting a stopped vehicle. The purpose is to provide.

  The invention according to claim 1 is a hydrogen detection sensor (for example, in the embodiment) that detects hydrogen based on a resistance value (for example, an electrical resistance value of the hydrogen sensor 23 in the embodiment) that changes in accordance with the presence or absence of hydrogen storage. A vehicle start control method comprising a hydrogen sensor 23) and a switch for instructing start and stop of the hydrogen detection sensor, wherein the resistance value changes when the hydrogen detection sensor is started by the switch. Starts within the predetermined range in which it can be determined that the vehicle can be allowed to start, while hydrogen is detected by the hydrogen detection sensor when the hydrogen detection sensor is started by the switch. In some cases, the temperature of the hydrogen detection sensor is raised to detect the hydrogen concentration, and the start of the vehicle is controlled in accordance with the hydrogen concentration.

  According to the present invention, since the resistance value of the hydrogen detection sensor changes by occluding hydrogen present in the surroundings regardless of whether the hydrogen detection sensor is activated or stopped, the hydrogen detection sensor is activated by the switch. If the change due to the resistance value is within a predetermined range, it can be determined that the hydrogen present around the hydrogen detection sensor is below a predetermined allowable concentration, so that the process can immediately proceed to the vehicle start-up process.

  Further, in the hydrogen detection sensor that detects hydrogen by the change in the resistance value, the resistance value tends to decrease as the hydrogen concentration increases, and the resistance value tends to increase as the temperature increases, thereby increasing the temperature. As a result, the range in which the hydrogen concentration can be detected can be expanded. Accordingly, when it is determined that hydrogen has been detected by the hydrogen detection sensor, the hydrogen concentration can be detected by increasing the temperature of the hydrogen detection sensor and expanding the detection range.

  According to the first aspect of the present invention, when the concentration of hydrogen present around the hydrogen detection sensor is equal to or lower than a predetermined allowable concentration, the time required for determination by the hydrogen detection sensor can be greatly shortened. Startability can be improved. In addition, since the power consumed by the hydrogen detection sensor can be greatly reduced, it is possible to contribute to an improvement in fuel consumption.

  Furthermore, since the start control of the vehicle suitable for the detected concentration can be performed when the hydrogen concentration is detected, the time required for determination by the hydrogen detection sensor can be shortened, and the startability of the vehicle can be improved. Can do. Moreover, since the electric power consumed by the hydrogen detection sensor can be reduced, the fuel consumption can be improved.

Hereinafter, a vehicle start control method according to an embodiment of the present invention will be described with reference to the drawings. In this embodiment, a case where the present invention is applied to a fuel cell vehicle using a fuel cell as a drive source will be described.
As shown in FIG. 1, for example, the vehicle start control system 1 according to the present embodiment includes a vehicle-side control device 2 and a portable terminal 3 that can be connected to the vehicle-side control device 2 through wireless communication. It is configured. Furthermore, the vehicle-side control device 2 is mounted on a vehicle 10 such as an electric vehicle including a fuel cell 6 as a power source, for example, and includes, for example, a current control device 11, a power storage device 12, a transmission / reception control device 13, Communication device 14, storage device 15, antenna 16, unlocking control device 17, door lock actuator 18, detection control device 19, alarm / ventilation control device 20, alarm device 21, and ventilation device 22 And a hydrogen sensor 23.

The fuel cell 6 is mounted as a power source of a vehicle such as an electric vehicle, for example, and further includes an electrolyte electrode structure in which a solid polymer electrolyte membrane made of, for example, a solid polymer ion exchange membrane is sandwiched between a fuel electrode and an oxygen electrode. A large number of fuel battery cells (not shown) sandwiched between a pair of separators are stacked.
For example, a fuel gas such as hydrogen supplied from a fuel gas supply unit such as a hydrogen tank (not shown) and supplied from an inlet-side pipe to the fuel electrode has a solid mass that is moderately humidified by hydrogen ionization on the catalyst electrode. Electrons generated during the movement to the oxygen electrode through the molecular electrolyte membrane are taken out to an external circuit and used as direct current electric energy. For example, since air containing an oxidant gas such as oxygen is supplied to the oxygen electrode from an air compressor (not shown) via the inlet side pipe, hydrogen ions, electrons, and oxygen react at the oxygen electrode. As a result, water is generated. Then, the so-called off-gas that has reacted is discharged from the outlet side piping on both the fuel electrode side and the oxygen electrode side.

The generated current extracted from the fuel cell 6 is input to a current control device 11 including, for example, a DC-DC chopper or the like, and a power storage device 12 is connected to the current control device 11.
The current control device 11 controls the current value of the generated current extracted from the fuel cell 6 based on the power generation command for the fuel cell 6 and also controls the current value of the current extracted from the power storage device 12 according to the state of the vehicle. To do.
The current control device 11 includes an activation switch that shifts the vehicle in a stopped state to a travelable state, for example, an IGSW interlocking power supply system to which power is supplied in conjunction with the on state of the ignition switch 25, and the activation switch. A non-interlocking power supply system to which power is supplied regardless of the on / off state is connected. For example, the IGSW interlocking power supply system includes an IGSW interlocking device 26 that includes a traveling motor, an air compressor, and the like.

The transmission / reception control device 13 provided in the non-interlocking power supply system transmits a calling signal at predetermined intervals to a predetermined range including the vehicle 10 via the communication device 14 and the antenna 16, for example. In response, a response signal returned from the portable terminal 3 is received. Then, for example, based on the strength of the received response signal or the like, it is determined whether or not the mobile terminal 3 is approaching the vehicle 10, and the terminal-side identification information included in the received response signal is stored in advance. 15 determines whether or not the vehicle-side identification information stored in 15 matches, and outputs a command signal instructing the operation of the unlocking control device 17 based on these determination results.
The unlocking control device 17 drives and controls a door lock actuator 18 that locks and unlocks the vehicle door. The unlocking and unlocking state of the vehicle door, the transmission / reception control device 13, and a detection control device 19 described later. A control signal is output to the door lock actuator 18 on the basis of the command signal output from. Furthermore, the information regarding the locked or unlocked state of the vehicle door is output to the detection control device 19 described later.

The detection control device 19 provided in the non-interlocking power supply system operates the hydrogen sensor 23 in accordance with information on the locking or unlocking state of the vehicle door output from the unlocking control device 17 and the state of the vehicle. It is determined whether or not the detected hydrogen concentration exceeds a predetermined concentration based on the detection signal output from. And the signal of this determination result, the command signal etc. which instruct | indicate operation | movement of the unlocking control apparatus 17 and the alarm / ventilation control apparatus 20 according to a determination result are output.
For example, the detection control device 19 is the terminal-side identification that matches the vehicle-side identification information in the transmission / reception control device 13 when the ignition switch 25 is in the off state (the vehicle is stopped) and the vehicle door is locked. When it is determined that the mobile terminal 3 that returns information is approaching the vehicle 10, the information is supplied from the power storage device 12 via the current control device 11 prior to the unlocking control device 17 unlocking the vehicle door. The hydrogen sensor 23 is operated by the generated electric power, and based on the detection signal output from the hydrogen sensor 23, it is determined whether or not the detected hydrogen concentration exceeds a predetermined concentration. For example, when the detected hydrogen concentration is less than a predetermined concentration, a command signal instructing unlocking of the vehicle door is output to the unlocking control device 17. On the other hand, for example, when the detected hydrogen concentration exceeds a predetermined concentration, a command signal instructing the operation of the alarm device 21 and the ventilation device 22 is output to the alarm / ventilation control device 20.

  The alarm / ventilation control device 20 receives a signal of the determination result from the detection control device 19, a command signal corresponding to the determination result, and when hydrogen exceeding a predetermined concentration is detected, for example, The alarm device 21 including a speaker that outputs an alarm sound or a voice message, a display that displays an alarm display, a lamp that is lit, and the like is operated. Further, the alarm / ventilation control device 20 activates a ventilation device 22 that ventilates, for example, a location where hydrogen exceeding a predetermined concentration is detected. For example, the vehicle window is opened or the air conditioner is activated for the passenger compartment.

  The mobile terminal 3 includes a terminal-side transmission / reception device 61, a terminal-side storage device 62, and a terminal-side antenna 63. When the terminal-side transmission / reception device 61 receives a call signal transmitted from the vehicle-side control device 2, Then, a response signal including the terminal-side identification information stored in advance in the terminal-side storage device 62 is returned via the terminal-side antenna 63.

Next, the configuration of an embodiment of the hydrogen sensor according to the present invention will be described with reference to the drawings. FIG. 2 is a cross-sectional view of the hydrogen sensor shown in FIG. FIG. 3 is a plan view of the hydrogen sensor shown in FIG.
As shown in these drawings, in the hydrogen sensor 23, a semiconductor layer (semiconductor) 42 is laminated on almost the entire upper surface of an insulating substrate (insulating base) 41, and particles are dispersed in an island shape at the center of the upper surface of the semiconductor layer 42. A hydrogen absorber 43 having an arranged structure is formed, and the inner electrodes 45 and 45 are disposed on the left and right sides of the previous hydrogen absorber 43 on the surface of the semiconductor layer 42, and the surface of the semiconductor layer 42. Outer electrodes 46, 46 are formed so as to be located on the left and right sides of the previous hydrogen absorber 43 and further outside the inner electrodes 45, 45. In the configuration of this embodiment, the hydrogen detector 44 is configured by the semiconductor layer 42 and the hydrogen absorber 43.

The insulating substrate (insulating base) 41 may be a substrate made of an insulating material such as a glass substrate such as SiO2, a quartz substrate, a ceramic substrate such as Al2O3, or an Si substrate as an insulating substrate not doped with ions. Since the insulating substrate 41 only needs to have an insulating property on the upper surface side, the insulating substrate 41 may be formed by coating an insulating layer on the surface of the conductive substrate.
The semiconductor layer 42 is a layered layer made of a semiconductor such as ITO (indium tin oxide), GaN, or n-type Si doped with P. This semiconductor layer is preferably an insulator, but it is desirable to use a semiconductor doped with ions.
As this type of semiconductor, an n-type semiconductor obtained by ion doping silicon with an element such as P, As or Sb, which is a group V element, or a p-type semiconductor obtained by ion doping silicon with a group III element such as B, etc. Can be used. In addition, n-type or p-type SiC, Ge, SiGe, GaAs, GaN, or the like can be used as a semiconductor for forming the semiconductor layer 42.

The hydrogen absorber (hydrogen-absorbing material body) 43 is made of particles of any of Pd, Pd alloy, Pt, and Pt alloy, or other platinum group elements or their alloy elements dispersed in an island shape. It is preferable that it is the structure made. This hydrogen absorber 43 absorbs hydrogen when hydrogen is present in the installation environment, and conversely releases the absorbed hydrogen when there is no hydrogen in the installation environment.
In addition to these metals, it is of course possible to use any of La, Ti, Zr, Mg, rare earth metals, Ca, V, or alloys containing these, which are generally known as hydrogen storage alloys. .

Here, the hydrogen absorber 43 is made of the above-described metal or alloy hydrogen absorbing material, but when these hydrogen absorbing materials are formed on the semiconductor layer 42, a pattern is not formed between the pair of electrodes to be formed later. It is necessary to. Photolithographic methods are preferably used for pattern formation. As another form, it is preferable that the particles are dispersed in an island-like state and do not have conductivity as a whole and function as an insulator.
In FIG. 2 and FIG. 3, the hydrogen absorber 3 is abbreviated as a film. 2 and 3, since the hydrogen absorber 43 is separated from the electrode, it is effective even if it is a continuous film. However, the hydrogen absorber 43 is an aggregate formed by separating particles into islands when enlarged. More preferably, the film thickness is such as to function as an insulator. For example, the hydrogen absorber 3 is an insulator having a resistance value of about 1 MΩ or more, and the hydrogen absorber 43 preferably has a thickness of about 0.5 nm to 5 nm.

  The island-like dispersed hydrogen absorber 43 is formed in a state before being formed as a film when a film is deposited by depositing particles on the semiconductor layer 42 by a film deposition method such as a vacuum deposition method or a sputtering method. It can be manufactured by stopping the membrane. For example, Pd, Pd alloy, Pt, Pt alloy, etc. are all highly conductive metal materials, and when formed as a film, become a conductor, so that the film formation is stopped in the state of an insulator before becoming a conductor. For example, the hydrogen absorber 43 having a structure in which a plurality of particles are dispersed and arranged in an island shape can be obtained. Therefore, the hydrogen absorber 43 as an insulator can be formed on the semiconductor layer 42 if it is formed in the range of the film thickness described above. In this embodiment, the vertical width of the hydrogen absorber 43 is slightly shorter than the vertical width of the insulating substrate 41, and the horizontal width is formed to be a fraction of the horizontal width of the insulating substrate 41. Therefore, the semiconductor layer 42 is exposed on both the left and right sides of the hydrogen absorber 43 in FIGS.

  The inner electrode 45 is formed on the upper surface of the semiconductor layer 42 so as to be separated from the hydrogen absorber 43 so as to be sandwiched between both sides of the hydrogen absorber 43. These inner electrodes 45 are made of a highly conductive metal material such as Au or Al, and are formed by a film forming method such as a vacuum evaporation method, a sputtering method, or a screen printing method. The outer electrode 46 is formed on both end sides of the semiconductor layer 42 at positions where the inner electrodes 45 are further sandwiched from both sides.

In order to detect hydrogen using the hydrogen sensor 23 configured as described above, the hydrogen sensor 23 is installed in a measurement environment, and a predetermined current is applied between the outer electrodes 46, 46 while the inner electrode 45, It is used by measuring the electrical resistance change of the semiconductor layer 42 itself by measuring the voltage between 45. Here, the measurement with the inner electrodes 45, 45 corresponds to a change in electrical resistance of the semiconductor layer 42 itself.
When hydrogen gas is present in the installation environment of the hydrogen sensor 23, hydrogen is taken into the hydrogen absorber 43 of the hydrogen sensor 23, and the portion of the semiconductor layer 42 that is in contact with the hydrogen absorber 43 absorbs hydrogen into the hydrogen absorber 43. As a result, the state of the charge carrier changes, and the resistance value of the semiconductor layer 42 changes due to this. In addition, when hydrogen disappears from the environment where the hydrogen sensor 23 of this example is installed, hydrogen is released from the hydrogen absorber 43, so that the resistance value of the semiconductor layer 42 returns to the origin and becomes usable again. When hydrogen gas is present again in the installation environment from this state, the resistance value of the semiconductor layer 42 changes again, so that the hydrogen sensor 23 of this example can be used repeatedly.
In addition, although the installation environment of the hydrogen sensor 23 may be normal temperature, it does not ask | require especially in an environment of higher temperature than that.

The vehicle start control system 1 according to the present embodiment has the above-described configuration. Next, the operation of the vehicle start control system 1 will be described with reference to FIG. FIG. 4 is a flowchart showing the operation of the vehicle start control system according to the embodiment of the present invention.
First, when the ignition switch is turned on (IG-ON), power is supplied from the power source to the hydrogen sensor 23 in step S12. In step S14, it is determined whether hydrogen is detected. In the present embodiment, this is performed depending on whether or not the electrical resistance value of the hydrogen absorber 43 provided in the hydrogen sensor 23 is lower than the detection threshold value R0. If the determination result is YES, the process proceeds to step S20, and if the determination result is NO, the process proceeds to step S16.

  This determination method will be described with reference to FIGS. FIG. 9 is a graph (PTC state diagram) showing the relationship between the hydrogen concentration in the metal included in the hydrogen sensor and the pressure of hydrogen contained in the surrounding gas. FIG. 10 is a graph showing the relationship between the hydrogen concentration in the atmosphere and the sensor detection unit resistance value. The two isotherms shown in FIG. 9 show the relationship between the pressure in the cross section of T1 and T2 of each temperature axis and the composition of the solid phase, and the vertical axis represents the equilibrium hydrogen pressure at each temperature and the horizontal axis. Indicates the ratio of hydrogen atoms H to metal atoms M in the solid phase. Note that the equilibrium hydrogen pressure is different in the process of storing and releasing hydrogen (because hysteresis exists), but is omitted in the figure.

  In FIG. 9, the hydrogen pressure on the vertical axis is the hydrogen partial pressure in the atmosphere and can be considered as the hydrogen concentration to be detected, and the hydrogen concentration in the metal on the horizontal axis corresponds to the hydrogen concentration of the hydrogen sensor 23. The detection unit 44 is electrically and magnetically affected. Therefore, it can be seen that the characteristics shown in FIG. For example, in the figure, when the hydrogen concentration C2 is considered as the detection target concentration, if the sensor detection resistance value falls below the detection threshold value R0 at the set upper limit temperature T2 or less, the hydrogen concentration is above a certain level and the vehicle It is determined that startup is not acceptable. Here, the set upper limit temperature T2 is a temperature set so as to be heated by, for example, a heater or the like in order to accurately detect the hydrogen concentration, and is higher than the detection threshold value R0 at the sensor temperature T1 (<T2) at the start of the vehicle. If a large resistance value is detected, it is found that the hydrogen concentration is sufficiently small to allow the vehicle to start.

  Therefore, if the determination result in step S14 is NO, it can be determined that the hydrogen concentration is sufficiently small to allow the vehicle to start, and thus the process proceeds to step S16 to start the fuel cell system. In step S18, the temperature of the hydrogen sensor 23 is heated to the set upper limit temperature T2 to increase the detection accuracy for after the fuel cell is started, and the processing of this flowchart ends.

  In step S20, it is determined whether or not the temperature of the hydrogen sensor 23 is equal to or lower than a set upper limit temperature T2. If this determination result is YES, the process proceeds to a step S22, and if this determination result is NO, the process proceeds to a step S28. In step S22, the heating process of the hydrogen sensor 23 is started, and the temperature of the hydrogen sensor 23 is increased. Thereafter, in step S24, it is determined whether or not hydrogen is detected, that is, whether or not the electrical resistance value of the hydrogen absorber 43 is lower than the detection threshold value R0. If the determination result is YES, the process proceeds to step S26, and if the determination result is NO, the process returns to step S20.

As described above with reference to FIGS. 9 and 10, even when a resistance value lower than the detection threshold value R0 is detected at the sensor temperature T1 at the time of starting the vehicle, the set upper limit temperature is used to accurately detect the hydrogen concentration. If the sensor resistance value exceeds the detection threshold value R0 in the process of heating to T2, it can be determined that the hydrogen concentration is a concentration that allows the vehicle to start at that time.
Therefore, if the determination result in step S24 is NO, it can be determined that the hydrogen concentration is an allowable concentration for starting the vehicle. Therefore, the process proceeds to step S26, and a stepwise response is performed according to the detected concentration. Specifically, light, sound, and radio alarm generation processing, processing that prompts ventilation or automatically activates a ventilation fan, processing that prompts or opens a vehicle window, and boarding a driver, etc. When the prospective person is approaching the vehicle, processing such as prohibiting door unlocking is performed step by step.

  In step S28, the heating process of the hydrogen sensor 23 is stopped, and the process proceeds to step S30. In step S30, since it can be determined that the detected hydrogen concentration is unacceptable for starting the vehicle, a hydrogen line shut-off process is performed, and the process of this flowchart ends.

  Hereinafter, the vehicle start process according to the value of the hydrogen concentration will be described with reference to FIGS. First, when the hydrogen concentration at start-up is less than C1% (FIG. 5), the hydrogen sensor 23 is turned on when the power switch (in this case, the ignition switch) 25 of the hydrogen detection system including the hydrogen sensor 23 is turned on. Since the detection resistance value R of the fuel cell has already exceeded the detection threshold value R0, it can be immediately determined that the hydrogen concentration is a concentration that allows the vehicle to start, so that the fuel cell can be started immediately. .

  Next, when the hydrogen concentration at start-up is C3% (C1 <C3 <C2) (FIG. 6), the detection resistance value R of the hydrogen sensor 23 is detected by the detection threshold R0 when the ignition switch 25 is turned on. However, if the hydrogen sensor 23 is heated for accurate detection, the resistance value R exceeds the detection threshold value R0 when the equilibrium hydrogen concentration C3% is reached. At this time, since it can be determined that the hydrogen concentration is a concentration that allows the vehicle to start, the fuel cell can be started immediately thereafter.

  Next, when the hydrogen concentration at start-up is C2% (FIG. 7), the detection resistance value R of the hydrogen sensor 23 falls below the detection threshold value R0 when the ignition switch 25 is turned on. Therefore, when the hydrogen sensor 23 is heated, the resistance value R exceeds the detection threshold value R0 when the equilibrium hydrogen concentration C2% is reached. At this time, since it can be determined that the hydrogen concentration is a concentration that allows the vehicle to start, the fuel cell can be started immediately thereafter.

  When the hydrogen concentration at the start exceeds C2% (FIG. 8), when the ignition switch 25 is turned on, the detection resistance value R of the hydrogen sensor 23 is below the detection threshold value R0, and accurate detection is performed. Therefore, even when the hydrogen sensor 23 is heated and reaches the equilibrium hydrogen concentration C2%, the resistance value R is below the detection threshold value R0. At this time, since it can be determined that the hydrogen concentration exceeds the concentration that allows the vehicle to start, the fuel cell is prohibited from starting and a predetermined operation is performed.

  Of course, the contents of the present invention are not limited to the above-described embodiments. For example, in the embodiment, after the hydrogen detection process is started, the process of heating the hydrogen sensor to a certain temperature T2 is performed. However, if it is not necessary to continue the hydrogen detection, the heating of the hydrogen sensor is terminated. Good. The number of hydrogen sensors is not particularly limited, and may be singular or plural.

In addition, as a hydrogen sensor having a hydrogen storage alloy, a semiconductor type, a field effect transistor (FET) type, an electric resistance detection type, an optical type, a surface acoustic wave (SAW), etc. A sound wave type may be used.
The start of the hydrogen sensor may be controlled by an IG sensor, or may be performed when it can be determined that a boarding person having a pre-registered mobile terminal 3 is approaching the vehicle 10. May be.

Further, as a method of measuring the temperature of the hydrogen sensor, it may be detected by an independent temperature sensor, or may be integrated (eg, HIC: Hybrid Integrated Circuit) in the manufacturing process of the hydrogen sensor element itself. .
In addition, even if the temperature at the time of detection value change (for example, increase in resistance value) of the sensor during heating is unknown, it is found that the hydrogen concentration is below the detection target threshold value. The fuel cell may be started after combining or performing a predetermined operation.
In the embodiment, the hydrogen concentration is determined based on a change in the resistance value of the hydrogen sensor. However, the present invention is not limited to this, and the hydrogen concentration is determined by detecting a weight change due to hydrogen storage using a crystal resonator or the like. May be performed.

1 is an overall configuration diagram of a vehicle start control system according to an embodiment of the present invention. It is sectional drawing of the hydrogen sensor shown in FIG. It is a top view of the hydrogen sensor shown in FIG. It is a flowchart which shows operation | movement of the start control system for vehicles which concerns on one Embodiment of this invention. It is a graph which shows the vehicle starting example in case hydrogen concentration is less than C1%. It is a graph which shows the vehicle starting example in case hydrogen concentration is C3%. It is a graph which shows the vehicle starting example in case hydrogen concentration is C2%. It is a graph which shows the vehicle starting example in case hydrogen concentration exceeds C2%. It is a graph which shows the relationship between the hydrogen concentration in the metal with which a hydrogen sensor is provided, and the pressure of the hydrogen which the gas of the circumference | surroundings contains. It is a graph which shows the relationship between the hydrogen concentration in air | atmosphere, and a sensor detection part resistance value.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Vehicle start-up control system 10 ... Vehicle 23 ... Hydrogen sensor 25 ... Ignition switch

Claims (1)

A hydrogen detection sensor that detects hydrogen by a resistance value that changes depending on whether hydrogen is stored or not;
A start control method for a vehicle, comprising: a switch for instructing start and stop of the hydrogen detection sensor;
When the hydrogen detection sensor is activated by the switch, if the change in the resistance value is within a predetermined range where it can be determined that the vehicle can be activated, the vehicle is started.
When hydrogen is detected by the hydrogen detection sensor when the hydrogen detection sensor is activated by the switch,
Increase the temperature of the hydrogen detection sensor to detect the hydrogen concentration,
A start control method for a vehicle, wherein the start of the vehicle is controlled in accordance with the hydrogen concentration.

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