JP4747513B2 - Gas supply device - Google Patents

Description

  The present invention relates to, for example, an in-vehicle gas supply device, and more particularly to a gas supply device capable of storing and supplying hydrogen gas.

  In this type of gas supply device, for example, pressure monitoring (monitoring) for a plurality of pressure sensors respectively provided near the supply ports of a plurality of high-pressure hydrogen gas storage tanks is performed independently, and a plurality of hydrogen gas storages are provided. Overall control is performed independently for tank switching.

  In relation to the pressure monitoring for the pressure sensor, Patent Document 1 discloses that the gas pressure measured by each pressure sensor is within a predetermined allowable range when each on-off valve (open / close valve) is opened from the closed state. A gas supply device that detects abnormality of each pressure sensor depending on whether or not is disclosed.

  Further, in relation to the overall control for switching between a plurality of hydrogen gas storage tanks, Patent Document 2 discloses that the gas pressure measured by the pressure sensor corresponding to the hydrogen gas storage tank that is supplying the gas is smaller than a predetermined threshold value. When the gas pressure decreases by a predetermined amount, the on-off valve corresponding to this hydrogen gas storage tank is driven to close, and at the same time, the on-off valve of the hydrogen gas storage tank with the largest amount of gas is opened. A gas supply device is disclosed in which a hydrogen gas storage tank is sequentially switched by driving a valve.

JP 2001-317695 A JP 2001-295996 A

  However, according to Patent Document 1, it is possible to detect an abnormality of the pressure sensor, but there is a technical problem that no fail-safe processing is performed after the detection of the abnormality.

  Further, according to Patent Document 2, when the gas pressure measured by the pressure sensor corresponding to the hydrogen gas storage tank that is supplying the gas is smaller than a predetermined threshold, the hydrogen gas storage tank is sequentially switched. If this pressure sensor fails, it will be impossible to continue supplying gas. More specifically, since only one pressure sensor is provided in each hydrogen gas storage tank, if this pressure sensor cannot perform normal measurement due to disconnection or ground short, pressure monitoring becomes impossible, and hydrogen It becomes impossible to switch the gas storage tank, and as a result, the supply of gas can be stopped, so-called out of gas, and further a road failure of the vehicle can be caused.

  Therefore, the present invention has been made in view of the above-described problems, for example, even in the case of a failure or abnormal situation such as a failure of a pressure sensor that monitors the pressure of a hydrogen gas storage tank, the gas supply is performed. It is an object to provide a gas supply device that can be continued.

In order to solve the above problems, a first gas supply apparatus of the present invention stores a gas storage means for storing a gas, a gas pressure detection means for detecting a gas pressure due to the gas inside the gas storage means, and the gas A gas pressure estimating means for estimating a pressure reduction amount, and the gas pressure based on the estimated gas pressure reduction amount, the detected gas pressure, and a gas pressure at the time of opening of the gas storage means; An abnormality detection means for detecting an abnormality of the detection means; and when the abnormality is not detected by the abnormality detection means, the gas supply control from the gas storage means is performed based on the detected gas pressure, and And supply control means for performing the supply control based on the estimated decrease amount of the gas pressure and the gas pressure when the gas storage means is opened when the abnormality is detected by the abnormality detection means.

  According to the first gas supply apparatus of the present invention, under the control of the supply control means, for example, the pressure monitoring for the gas pressure detection means provided near the supply port of the gas storage means such as a high-pressure hydrogen gas storage tank is performed. At the same time, opening / closing driving of an opening / closing valve or the like provided in the gas storage means is performed, and gas supply is continuously performed.

  In particular, the supply control means performs supply control of the gas from the gas storage means based on the detected gas pressure when no abnormality is detected by the abnormality detection means, and when abnormality is detected by the abnormality detection means. The supply control is performed based on the estimated gas pressure.

  Thus, when an abnormality is detected by the abnormality detection means, the gas pressure can be continuously monitored by estimating the gas pressure by the gas pressure estimation means. Here, “estimation” in the present invention does not directly detect or measure the gas pressure by the gas pressure detection means, but indirectly by other scientific phenomena such as an electrochemical reaction of hydrogen gas. Is to measure the gas pressure. More specifically, the amount of hydrogen gas consumed is calculated based on the output current of a fuel cell that generates power using hydrogen gas as fuel, and the amount of decrease in gas pressure is further calculated, whereby the gas pressure inside the gas storage means is calculated. Is indirectly obtained.

  As described above, even when the abnormality of the gas pressure detecting means is detected by the abnormality detecting means, it is possible to continuously control the gas supply. Accordingly, it becomes possible to prevent the gas supply from being uncontrollable due to the detection of the abnormality of the gas pressure detecting means, the gas supply stop accompanying it, the so-called gas shortage, and further the road failure of the vehicle.

In one aspect of the first gas supply apparatus of the present invention, the gas storage device includes a plurality of the gas storage units, the plurality of abnormality detection units corresponding to the gas storage units, and the supply control unit includes the plurality of gas storage units. Among the gas storage means, the gas storage means corresponding to the one gas pressure detection means detected to be abnormal by the abnormality detection means, the amount of decrease in the estimated gas pressure and the one of the gas storage means The supply control is performed based on the gas pressure when the valve is opened .

  According to this aspect, when an abnormality of at least one gas pressure detecting means is detected by the abnormality detecting means, the gas storage means corresponding to the gas pressure detecting means in which the abnormality is detected under the control of the supply control means. The supply control is performed based on the estimated gas pressure. Therefore, it is possible to continuously monitor the gas pressure by estimating the gas pressure.

  As described above, even when the abnormality of the gas pressure detecting means is detected by the abnormality detecting means, it is possible to continuously control the gas supply. Therefore, it is possible to continue switching among the plurality of gas storage means. Therefore, the control of gas supply due to the detection of the abnormality of the pressure sensor, the accompanying switching of the gas storage means, the stoppage of the gas supply accompanying it, the so-called gas shortage, and further the failure on the road of the vehicle. This can be prevented beforehand.

  In addition, instead of switching all of the plurality of gas storage means, only the gas storage means in which an abnormality has occurred is switched to a gas pressure estimation means that is less accurate than the gas pressure detection means, so that the gas supply can be continued with higher accuracy. It is possible to control.

  In this aspect, the plurality of gas storage units are connected in parallel, and the supply control unit detects the gas storage unit that is supplying the gas among the plurality of gas storage units. Alternatively, when the estimated gas pressure falls below a predetermined threshold, the supply control may be performed so that the gas is supplied from another gas storage means instead of the one gas storage means. .

  If comprised in this way, switching of a some gas storage means will be performed under control of a supply control means. More specifically, when the gas pressure detected by the gas pressure detecting means corresponding to one gas storage means that is supplying the gas is smaller than a predetermined threshold value, or when the gas pressure is decreased by a predetermined amount. The open / close valve corresponding to this one gas storage means is driven to close, and at the same time, the open / close valve of the other gas storage means having the highest gas pressure is driven to open and sequentially switch to the other gas storage means. .

  From the above, it is possible to realize more accurate overall control under the control of the supply control means.

  In this aspect, the supply control means may include a plurality of on-off valves that correspond to the plurality of gas storage means and that can be opened and closed independently of each other.

  With this configuration, it is possible to realize more accurate overall control under the control of the supply control means.

In this aspect, the gas supply path includes a plurality of branch portions respectively connected to the plurality of gas storage means , and a main body portion formed by synthesizing the plurality of branch portions. And a measuring means for measuring at least one parameter of the pressure and flow rate of the gas in the main body, and the supply control means, when the measured parameter falls below a predetermined threshold, You may comprise so that the gas storage means which supplies the said gas in order with the said detected or estimated gas pressure among these gas storage means may be switched.

  According to this structure, at least one of the pressures and flow rates of the entire gas supplied from the plurality of gas storage units is constantly monitored by the measurement unit. It is possible to continuously control the gas supply regardless of the unstable factors.

  In another aspect of the first gas supply device of the present invention, the gas supply device further comprises current measuring means for measuring an output current output by power generation of a fuel cell that generates power using the gas as fuel. The gas pressure is estimated based on the measured output current.

  According to this aspect, the gas pressure estimating means indirectly obtains the gas pressure inside the gas storage means based on the output current measured by the current measuring means. More specifically, the reduction amount of the gas pressure can be obtained by integrating the output current from the fuel cell with the gas supply time. Therefore, the amount of decrease in the gas pressure can be obtained indirectly by multiplying the calculated value obtained by time integration of the output current measured by the current measuring means by the conversion coefficient.

  As described above, even when the abnormality of the gas pressure detecting means is detected by the abnormality detecting means, it is possible to continuously control the gas supply. Therefore, it is possible to prevent the gas supply from being uncontrollable due to the detection of the abnormality of the gas pressure detecting means, the gas supply stop accompanying it, the so-called gas shortage, and further the road failure of the vehicle. Become.

  In this aspect, the apparatus further comprises gas consumption calculation means for calculating a gas consumption from the measured output current, and the gas pressure estimation means estimates the gas pressure based on the calculated gas consumption. You may comprise as follows.

  If comprised in this way, a gas pressure estimation means will calculate gas consumption based on the output current of the fuel cell which produces | generates gas as a fuel, and also calculates the reduction | decrease amount of gas pressure, and gas storage means The gas pressure inside is indirectly determined. More specifically, the decrease amount of the gas pressure is proportional to the gas consumption amount (for example, the number of moles) consumed by the fuel cell. This gas consumption can be obtained by integrating the output current from the fuel cell with the gas supply time. Therefore, the amount of decrease in the gas pressure can be obtained indirectly by multiplying the calculated value obtained by time integration of the output current measured by the current measuring means by the conversion coefficient.

  In another aspect of the first gas supply apparatus of the present invention, when the abnormality is detected, the gas pressure estimation unit detects the past detected by the gas pressure detection unit before the abnormality is detected. The gas pressure is estimated based on the gas pressure.

  According to this aspect, since the gas pressure is estimated by the gas pressure detection means based on, for example, a highly accurate gas pressure detected in the most recent past, it is possible to estimate the gas pressure with higher accuracy. It becomes.

In order to solve the above-described problem, the second gas supply device of the present invention detects or estimates a plurality of gas storage means for storing gas, and a gas pressure due to the gas in each of the gas storage means. The main body of the gas supply path, comprising: a gas pressure acquisition unit configured to perform; a plurality of branches connected to the plurality of gas storage units; and a main body formed by combining the plurality of branches. measuring means for measuring at least one parameter of the pressure and flow rate of the gas in the main body while being arranged in parts, when the measured parameter falls below a predetermined threshold value, the plurality of gas storage means Supply control means for performing the supply control so as to switch the gas storage means for supplying the gas in descending order of the detected or estimated gas pressure .

  According to the second gas supply apparatus of the present invention, since at least one parameter of the pressure and flow rate of the entire gas supplied from the plurality of gas storage means is constantly monitored by the measurement means, the gas pressure detection is performed. Regardless of other unstable factors such as abnormality of means, it is possible to continuously control the gas supply. Specifically, for example, the gas pressure acquisition means including the gas pressure estimation means is affected by a decrease in temperature in the gas storage means. That is, an estimation error of the gas pressure (decrease amount) occurs due to a decrease in temperature in the gas storage means. It is possible to prevent gas supply stoppage caused by this estimation error, so-called out-of-gassing, and further failure of the vehicle on the road.

  If the parameter measured by the measurement unit is not determined, the estimated gas pressure described above includes a measurement error that is affected by a decrease in temperature in the gas storage unit. That is, when a large amount of gas is supplied rapidly, the gas pressure is reduced to a value higher than the actual gas supply amount due to a decrease in temperature in the gas storage means based on the adiabatic expansion of the gas. Therefore, when the amount of gas in the gas storage means is small, switching of the gas storage means is delayed due to a measurement error, causing gas supply stoppage, so-called gas shortage.

  On the other hand, according to the gas supply device of the present invention, when the measuring means constantly monitors the pressure and falls below a predetermined threshold value, the gas storage means that is scheduled to supply the gas immediately next time. And switch. Accordingly, it is possible to prevent the gas supply stoppage, that is, the so-called gas shortage caused by the estimation error of the gas pressure, which is affected by the temperature drop in the gas storage means, and further the road failure of the vehicle.

  According to the gas supply device of the present invention, it is possible to continue the gas supply even in the case of a failure or abnormal situation, for example, when the pressure sensor that monitors the pressure of the hydrogen gas storage tank fails. .

  Hereinafter, specific embodiments according to the gas supply apparatus of the present invention will be described with reference to the drawings.

(First Embodiment of Gas Supply Device)
The configuration and operation of the first embodiment of the gas supply apparatus of the present invention will be described in detail with reference to FIGS.

  First, with reference to FIG.1 and FIG.2, the structure which concerns on 1st Embodiment of the gas supply apparatus of this invention is demonstrated. FIG. 1 is a schematic configuration diagram showing the overall configuration of a fuel cell system including the gas supply device according to the first embodiment of the gas supply device of the present invention. FIG. 2 is a conceptual diagram showing an electronic control unit (ECU), various sensors, various valves, and the like that control the gas supply apparatus according to the first embodiment of the gas supply apparatus of the present invention.

  As shown in FIG. 1, a fuel cell (FC) system including a gas supply device according to a first embodiment of the gas supply device of the present invention is roughly classified into a gas supply device 10 and the gas supply. The fuel cell stack 60 generates electricity by receiving hydrogen supplied from the apparatus 10, and the fuel supply pipe 122 that constitutes an example of the “supply path” of the present invention that connects the gas supply device and the fuel cell stack. ing.

  Furthermore, the gas supply apparatus 10 includes a plurality of hydrogen storage high-pressure tanks (hereinafter referred to as “tanks”) TK1 to TKn and an ECU 50 that controls the entire apparatus.

  The tanks TK1 to TKn are pressure reducing devices 31 to 3n, pressure sensors P1 to Pn constituting an example of the “gas pressure detecting means” of the present invention, open / close valves 21 to 2n constituting an example of the “open / close valve” of the present invention, Temperature sensors T1 to Tn and temperature controllers HT1 to HTn are provided.

  The pressure reducing devices 31 to 3n reduce the pressure of hydrogen supplied from the upstream side to the downstream side of the pressure reducing devices 31 to 3n to a constant value. More specifically, even if the upstream side of the decompression device 31 to 3n is, for example, 40 MPa (Mega Pascal) or 4 MPa, the downstream side of the decompression device 31 to 3n is decompressed to, for example, 3 MPa. The

  The pressure sensors P1 to Pn measure the pressure inside the tanks TK1 to TKn on the upstream side of the decompression devices 31 to 3n.

  Open / close valves 21 to 2n are provided at the outflow inlets of the respective tanks TK1 to TKn, the downstream side of which is connected to the fuel supply pipe 122 on the anode side of the fuel cell stack 60, and the fuel cells from the tanks TK1 to TKn. Hydrogen can be supplied to the stack 60.

  The temperature sensors T1 to Tn measure the temperature inside the tanks TK1 to TKn on the downstream side of the decompression devices 31 to 3n.

  Temperature controllers HT1 to HTn adjust the temperature inside tanks TK1 to TKn. More specifically, the temperature controllers HT1 to HTn are provided with circulation channels that heat or cool the tanks TK1 to TKn by heat exchange with a heat exchange medium (for example, water), and the circulation channels. You may comprise the valve | bulb etc. which open and close.

  As shown in FIGS. 1 and 2, the ECU 50 includes a CPU (Central Processing Unit) 51, a ROM (Read Only Memory) 52, a RAM 53 for temporarily storing data, a backup RAM 54, and the like. It is a computer, and the CPU performs overall control of the gas supply device at normal time and abnormal time according to a program recorded in the ROM 52. The ECU 50 constitutes an example of “supply control means” according to the present invention.

  The ECU 50 includes pressure sensors P1 to Pn, a current sensor 61 that measures the output current of the fuel cell stack, temperature sensors T1 to Tn that measure the temperature in each tank, a timer that measures time, and other various sensors. These various signals are input. The current sensor 61 constitutes an example of “current measuring means” according to the present invention. The current sensor 61 and the ECU 50 described above constitute an example of the “gas pressure estimating means” according to the present invention.

  The ECU 50 outputs the following control signal in response to the input signal described above.

  As will be described later, the ECU 50 determines whether there is an abnormality in the pressure sensors P1 to Pn based on the comparison between the first predetermined threshold and the deviation between the tank pressure Pn_T measured by the pressure sensors P1 to Pn and the comparison pressure Pstd. It is determined whether or not it is detected. Based on this determination, a control signal is output to various arithmetic circuits (not shown) or the like in order to obtain the tank pressure decrease estimated amount ΔP ′.

  Further, as will be described later, in order to compare the tank internal pressure Pn_0 immediately after the valve opening and the tank internal pressure Pn_T measured after T seconds and the second predetermined threshold, Based on this, it is determined whether or not to switch the tank. Based on this determination, a control signal for driving the on / off valves 21 to 2n is output.

  Further, as will be described later, a control signal for driving HTn from the temperature controller HT1 to heat the tank TKn that is currently supplying hydrogen and the tank TKn + 1 that is next scheduled to be supplied with hydrogen. Is output.

  Further, the ECU 50 communicates with a fuel cell electronic control unit (not shown) (hereinafter referred to as “FC ECU: Fuel Cell Electrical Control Unit”) for controlling the fuel cell stack 60 described later via a communication port or the like. Good.

  The fuel cell stack 60 generates electricity by an electrochemical reaction using hydrogen supplied from the gas supply device 10 via the fuel supply pipe 122 and oxygen in the air supplied by a blower (not shown). A load (not shown) is connected to the output terminal of the fuel cell stack 60 so that power can be supplied from the fuel cell stack 60 to the load. A current sensor 61 for detecting an output current is attached between the output terminals of the fuel cell stack 60, and the detection signal is input to the ECU 50 through a signal line.

(Gas Supply Control Processing Routine-First Embodiment)
Next, referring to FIGS. 1 and 2 as appropriate in addition to FIGS. 3 to 5, hydrogen is supplied from a plurality of tanks to the fuel cell stack according to the first embodiment of the gas supply apparatus of the present invention. The gas supply control for performing the fail-safe process when the control of the switching operation of the tank during the operation and the abnormality of the pressure sensor is detected will be described. Here, FIG. 3 shows the control of the tank switching operation when the hydrogen is supplied from the plurality of tanks to the fuel cell stack according to the first embodiment of the gas supply apparatus of the present invention, and the abnormality of the pressure sensor. It is a flowchart figure which shows the gas supply control processing routine which performs the fail safe process at the time of being detected. FIG. 4 is a flowchart showing a pressure sensor diagnostic process for detecting an abnormality of the pressure sensor in the tank, which is a subroutine in the gas supply control process routine according to the first embodiment of the gas supply apparatus of the present invention. FIG. 5 is a flowchart showing an empty determination process for determining whether or not the inside of the tank, which is a subroutine in the gas supply control process routine according to the first embodiment of the gas supply apparatus of the present invention, has become empty due to gas consumption. FIG. Here, “empty” according to the present embodiment refers to a state in which the gas in the tank is almost or completely consumed, and hydrogen is not sufficiently supplied from the tank to the fuel cell stack.

  This gas supply control processing routine is a routine stored in the ROM of the CPU in advance, and is a routine executed mainly by the CPU periodically or irregularly during the operation in which the gas supply device supplies hydrogen. It is. This routine is preferably executed in a sufficiently short time (for example, on the order of a few msec or a few μsec), so that even when a pressure sensor abnormality is detected, various routines are performed at an appropriate timing. It is possible to execute control and fail-safe processing.

  As shown in FIG. 3, first, when the gas supply control processing routine is executed, under the control of the CPU 51 of the ECU 50, pressure sensor diagnosis processing for detecting abnormality of the pressure sensor in the tank is performed (step S100). . The subroutine of the pressure sensor diagnosis process will be described with reference to FIG.

  Next, under the control of the CPU 51 of the ECU 50, an empty determination process is performed to determine whether or not the gas in the tank is completely consumed and the tank is empty (step S110). This empty determination process subroutine will be described later with reference to FIG.

  Next, under the control of the CPU 51 of the ECU 50, the pressure sensor Pn detects a pressure change dP generated by supplying gas to the tank TKn that is currently supplying hydrogen (step S120).

  Subsequently, under the control of the CPU 51 of the ECU 50, it is determined whether or not the pressure change amount dP is larger than a first predetermined threshold value X1 (step S121). Here, the “first predetermined threshold value X1” is set as a lower limit value or a higher value of the pressure required to supply the fuel cell stack 60 as a hydrogen consuming device, This is a reference pressure value used for judgment. This first predetermined threshold value can be obtained by, for example, experimental, empirical, theoretical or simulation. Specifically, under the control of the CPU 51, the value of the pressure sensor is constantly monitored, and when a certain amount of hydrogen is consumed, that is, when the tank internal pressure is reduced by the first predetermined threshold value X1, the tank is switched to another tank. More specifically, when the opening / closing valve 21 of the tank TK1 having the highest pressure value among the pressure sensors P1 to Pn is opened and the pressure in the tank TK1 decreases by the first predetermined threshold value X1 or more, it is provided in the tank TK1. The opening / closing valve 22 provided in the tank TK2 having the highest tank internal pressure among the remaining tanks is opened at the same time as the opening / closing valve 21 is closed. Here, when the pressure change amount dP is larger than the first predetermined threshold value X1 (step S121: Yes), under the control of the CPU 51 of the ECU 50, the empty determination flag F to be described later is from the tank TK that is not “On”. Then, the tank TKn + 1 scheduled to supply hydrogen next is selected (step S122). As an algorithm for performing this selection, it may be selected in the order of the remaining amount of hydrogen, that is, in order from the one having the highest pressure in the tank, or switching based on the temperature in each tank. A predetermined sequence may be used. In addition, according to the research by the inventors of the present application, switching the tanks for supplying hydrogen among a plurality of tanks as described above suppresses a decrease in temperature in the tanks based on adiabatic expansion of hydrogen as much as possible. This is because, for example, deterioration of components such as rubber products is prevented.

  Subsequently, the open / close valve 2n + 1 provided in the selected tank TKn + 1 is opened under the control of the CPU 51 of the ECU 50 (step S123).

  Subsequently, under the control of the CPU 51 of the ECU 50, the open / close valve 2n provided in the tank TKn currently supplying hydrogen is closed, and this routine is ended (step S124).

  On the other hand, as a result of the determination in step S121, also when this pressure change amount dP is not larger than the first predetermined threshold value X1 (step S121: No), this routine is ended.

(Pressure sensor diagnosis processing subroutine)
Next, referring to FIG. 4, a pressure sensor diagnosis process for detecting an abnormality of the pressure sensor in the tank, which is a subroutine in the gas supply control process routine, will be described.

  First, the tank internal pressure Pn_0 at the time (t = 0) when the valve TKn currently supplying hydrogen is started and the current (t = T) tank internal pressure Pn_T are obtained from the RAM 52 in the ECU 50. Obtained (step S101).

  Next, under the control of the CPU 51, the tank pressure decrease amount ΔP is estimated (hereinafter, this estimated decrease amount is referred to as “tank pressure decrease estimated amount ΔP ′”) (step S102). More specifically, the tank pressure decrease amount ΔP is proportional to the hydrogen consumption (in mol) consumed by the fuel cell stack 60. This hydrogen consumption amount ΔH can be obtained by time-integrating the output current A from the fuel cell stack 60 from t = 0 at the start of hydrogen supply to t = T. Therefore, the tank pressure decrease estimated amount ΔP ′ can be obtained by multiplying the operation value obtained by time integration of the output current A measured by the current sensor 61 by the conversion coefficient K. That is, the estimated tank pressure decrease amount ΔP ′ is calculated by the following equation (1) or (2).

Tank pressure decrease estimated amount ΔP ′ = conversion coefficient K × hydrogen consumption amount ΔH (1)
Tank pressure decrease estimated amount ΔP ′ = conversion coefficient K × output current A × monitoring time ΔT (2)
Subsequently, it is determined whether or not the output voltage of the pressure sensor Pn is within a predetermined range indicating normal operation (step S103). Here, when the output voltage of the pressure sensor Pn is within a predetermined range indicating normal operation (step S103: Yes), the measured current tank pressure Pn_T (t = T) It is determined whether or not Pn is within a predetermined range indicating normal operation (step S104). Here, when the measured in-tank pressure Pn_T at the present time (t = T) is within a predetermined range indicating normal operation of the pressure sensor Pn (step S104: Yes), further, under the control of the CPU 51. , “Tank pressure Pn_0” − “tank pressure Pn_T” − “tank pressure decrease estimated amount ΔP ′” is calculated, and it is determined whether or not this calculated value is smaller than a second predetermined threshold value X2 ( Step S105). Here, the “second predetermined threshold value X2” is a reference pressure value set as an error allowed for the pressure sensor or a slightly larger value. Here, when the calculated value is smaller than the second predetermined threshold value X2 (step S105: Yes), the pressure “P” in the tank is measured as the pressure sensor Pn operates normally (t = It is determined that the tank internal pressure Pn_T is T) (step S106).

  On the other hand, as a result of the determination in step S103, if the output voltage of the pressure sensor Pn is not within the predetermined range indicating normal operation (step S103: No), the measured current (t = When the tank internal pressure Pn_T in T) is not within the predetermined range indicating the normal operation of the pressure sensor Pn (step S104: No), and as a result of the determination in step S105, the calculated value is the second predetermined threshold value X2. When it is not smaller (step S105: No), it is determined that an abnormality has occurred in the pressure sensor Pn. More specifically, the abnormality of the pressure sensor Pn means that the increase or decrease in pressure value is not measured or measured even though hydrogen in the tank is consumed due to disconnection or ground short. This is a phenomenon such that the tank internal pressure Pn_T indicates a value exceeding the maximum value or the minimum value.

  Subsequently, under the control of the CPU 51, a value of “tank pressure Pn — 0” − “tank pressure decrease estimated amount ΔP ′” is calculated, and this calculated value is determined as the pressure “P” in the tank (step) S108). Thus, the calculated pressure “P” in the tank does not depend on the measured value of the pressure sensor Pn.

  As described above, this subroutine is completed.

(Empty judgment processing subroutine)
Next, an empty determination process for determining whether or not the inside of the tank, which is a subroutine in the gas supply control process routine, has become empty due to gas consumption will be described with reference to FIG.

  First, it is determined whether or not the pressure “P” in the tank is smaller than a third predetermined threshold value X3 (step S121). Here, the “third predetermined threshold value X3” includes an error allowed for the pressure sensor and the like, and determines whether or not the gas in the tank is completely consumed and the tank is empty. Possible pressure value. Here, when the pressure “P” in the tank is smaller than the third predetermined threshold value X3 (step S121: Yes), the empty determination flag F corresponding to the tank TKn that is currently supplying hydrogen is set to “On”. It is set (step S122).

  On the other hand, as a result of the determination in step S121, when the pressure “P” in the tank is not smaller than the third predetermined threshold value X3 (step S121: No), the above-described step S122 is omitted.

  As described above, this subroutine is completed.

  As described above, in the first embodiment, when an abnormality of the pressure sensor is detected, instead of the pressure sensor, the hydrogen consumption is calculated based on the output current of the fuel cell, and the pressure decrease in the tank is estimated. It is possible to continue the tank switching. Therefore, it becomes possible to prevent the tank from being switched due to the detection of the abnormality of the pressure sensor, the gas supply stop accompanying it, so-called out of gas, and further failure on the road of the vehicle.

(Second Embodiment of Gas Supply Device)
Next, with reference to FIG. 6, the structure which concerns on 2nd Embodiment of the gas supply apparatus of this invention is demonstrated. FIG. 6 is a schematic configuration diagram showing the overall configuration of the fuel cell system including the gas supply device according to the second embodiment of the gas supply device of the present invention.

  The configuration of the gas supply device according to the second embodiment shown in FIG. 6 is substantially the same as that of the first embodiment shown in FIGS. 1 and 2 described above.

  In particular, the gas supply apparatus according to the second embodiment further includes a tank outlet pressure sensor Pa that constitutes an example of the “measuring means” of the present invention.

  The tank outlet pressure sensor Pa is provided in the fuel supply pipe 122 that communicates the fuel supply stack 60 with the gas supply apparatus 10 that includes the plurality of tanks TK1 to TKn, and the gas that flows through the fuel supply pipe 122. The flow rate is measured in addition to or instead of the pressure.

(Gas Supply Control Processing Routine-Second Embodiment)
Next, with reference to FIG. 7, the gas supply control process which concerns on 2nd Embodiment of the gas supply apparatus of this invention is demonstrated. FIG. 7 is a flowchart showing a gas supply control processing routine according to the second embodiment of the gas supply apparatus of the present invention.

  This gas supply control processing routine is mainly executed by the ECU 50, and the configuration of the ECU 50 and the like is the same as that of the gas supply control processing routine according to the first embodiment described above. In FIG. 7, steps similar to those in FIG. 3 showing the gas supply control processing routine according to the first embodiment are given the same step numbers, and description thereof will be omitted as appropriate.

  In FIG. 7, Step S100 to Step S124 are the same as FIG. 3 showing the gas supply control processing routine according to the first embodiment described above.

  In the gas supply control process according to the second embodiment shown in FIG. 7, it is determined whether or not the measured value of the tank outlet pressure sensor Pa is smaller than a predetermined minimum value Pmin, particularly under the control of the ECU 50 (step S201). ). Here, the “predetermined minimum value” is the minimum pressure or flow rate of hydrogen gas necessary for continuing the operation of the vehicle. Such a determination is made in the ECU 50 using, for example, the output signal of the tank outlet pressure sensor Pa as an input parameter. Here, when the measured value of the tank outlet pressure sensor Pa is smaller than the predetermined minimum value (step S201: Yes), the open / close valves provided in all the tanks TK other than the tank TKn + 1 are once opened and the tanks The empty determination flag F of TKn + 1 is set to “On” (step S202).

  Subsequently, the empty determination process described with reference to FIG. 5 is performed on all the tanks TK (step S203). Here, when all the tanks TK are empty (step S203: Yes), in order to continue supplying gas as much as possible, the open / close valves provided in all the tanks TK are opened (step S204).

  On the other hand, if all the tanks TK are not empty as a result of the determination in step S203 (step S203: No), the tank TKn + 2 to be supplied is selected from the tanks TK other than the empty determination flag F being “On”. (Step S205). More specifically, the tank TKn + 2 to be supplied may be selected, for example, in the order in which the remaining amount of hydrogen is large, or may be selected in a predetermined sequence.

  Subsequently, the open / close valves of the tanks other than the selected tank TKn + 2 are closed, and only the open / close valve of the selected tank TKn + 2 is opened to open (step S206).

  On the other hand, as a result of the determination in step S201, when the measured value of the tank outlet pressure sensor Pa is not smaller than the predetermined minimum value (step S201: No), the gas supply control processing routine is ended.

  As described above, in the second embodiment, it is possible to suppress the influence of the estimation error of the tank pressure decrease amount ΔP due to the temperature drop in the tank. Accordingly, it is possible to prevent a delay in tank switching caused by this estimation error, a decrease in gas supply accompanying the delay, a lack of gas, and a road breakdown of the vehicle.

  If the measurement value of the tank outlet pressure sensor Pa is not determined, the tank pressure decrease estimated value ΔP ′ of the first embodiment described above includes a measurement error that is affected by a decrease in the temperature in the tank. That is, if hydrogen is consumed rapidly, the pressure in the tank also decreases to more than the actual hydrogen consumption due to a decrease in the temperature in the tank based on the adiabatic expansion of hydrogen. Therefore, when the amount of hydrogen in the tank is small, the switching of the tank is delayed due to a measurement error, which causes gas supply stoppage, so-called gas shortage.

  On the other hand, in the second embodiment, the tank outlet pressure sensor Pa constantly monitors the pressure, and when the pressure becomes equal to or lower than the predetermined minimum value, the tank is immediately switched to the next tank to be supplied with hydrogen. Therefore, it is possible to prevent gas supply stoppage, so-called gas shortage caused by an estimation error of the tank pressure decrease amount ΔP, which is affected by a decrease in the tank temperature, and further failure of the vehicle on the road. In addition, if the measured value of the tank outlet pressure sensor Pa is smaller than the predetermined minimum value Pmin, even if a delay occurs in the opening / closing operation of the opening / closing valve of at least one tank TK, the aforementioned so-called gas shortage occurs. Can be prevented.

  In addition, it is possible to enjoy the same effect as in the first embodiment.

  In the gas supply device 10 of the present embodiment, the hydrogen storage high-pressure tanks TK1 to TKn may supply gas other than hydrogen.

  Moreover, although the gas supply apparatus 10 of this embodiment was demonstrated as what mounts the gas supply apparatus 10 in a vehicle, it is good also as what is not mounted in a vehicle.

  The present invention is not limited to the above-described embodiment, and can be appropriately changed without departing from the gist or concept of the invention that can be read from the claims and the entire specification. A gas supply apparatus that includes such a change is also possible. Moreover, it is included in the technical scope of the present invention.

1 is a schematic configuration diagram illustrating an overall configuration of a fuel cell system including a gas supply device according to a first embodiment of a gas supply device of the present invention. It is a conceptual diagram which shows the electronic control unit (ECU: Electrical Control Unit), various sensors, various valves, etc. which control the gas supply apparatus which concerns on 1st Embodiment of the gas supply apparatus of this invention. According to the first embodiment of the gas supply device of the present invention, the control of the switching operation of the tank when supplying hydrogen from the plurality of tanks to the fuel cell stack, and the fail-safe when the abnormality of the pressure sensor is detected It is a flowchart figure which shows the gas supply control processing routine which performs a process. It is a flowchart figure which shows the pressure sensor diagnostic process which detects abnormality of the pressure sensor in a tank which is a subroutine in the gas supply control processing routine which concerns on 1st Embodiment of the gas supply apparatus of this invention. The flowchart which shows the empty determination process which determines whether the gas in the tank which is a subroutine in the gas supply control processing routine which concerns on 1st Embodiment of the gas supply apparatus of this invention was completely consumed, and the tank became empty. FIG. It is the schematic block diagram which showed the whole structure of the fuel cell system containing the gas supply apparatus which concerns on 2nd Embodiment of the gas supply apparatus of this invention. It is a flowchart figure which shows the gas supply control processing routine which concerns on 2nd Embodiment of the gas supply apparatus of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Gas supply device, 21 to 2n ... Open / close valve, 31 to 3n ... Pressure reducing device, 50 ... ECU, 51 ... CPU (Central Processing Unit), 52 ... ROM (Read Only Memory), 53 ... RAM, 54 ... Backup RAM , 60 ... Fuel cell stack, 61 ... Current sensor, 110 ... Fuel cell system, 122 ... Fuel supply pipe, HT1 to HTn ... Temperature controller, P1 to Pn ... Pressure sensor, Pa ... Tank outlet pressure sensor, TK1 to TKn ... Hydrogen storage high pressure tank (tank), T1 to Tn ... Temperature sensor

Claims (9)

Gas storage means for storing gas; and
Gas pressure detecting means for detecting a gas pressure by the gas inside the gas storage means;
Gas pressure estimating means for estimating the amount of decrease in the gas pressure;
An abnormality detection means for detecting an abnormality of the gas pressure detection means based on the estimated amount of decrease in the gas pressure, the detected gas pressure, and the gas pressure at the time of opening of the gas storage means;
When the abnormality is not detected by the abnormality detection unit, the gas supply control from the gas storage unit is performed based on the detected gas pressure, and the abnormality is detected by the abnormality detection unit. And a supply control means for performing the supply control based on the estimated amount of decrease in the gas pressure and the gas pressure when the gas storage means is opened. A plurality of the gas storage means;
A plurality of the abnormality detection means corresponding to the plurality of gas storage means,
The supply control means reduces the estimated gas pressure for a gas storage means corresponding to one gas pressure detection means detected as abnormal by the abnormality detection means among the plurality of gas storage means. The gas supply device according to claim 1, wherein the supply control is performed based on the amount and the gas pressure when the one gas storage means is opened. The plurality of gas storage means are connected in parallel,
The supply control means is configured to supply the one gas when the detected or estimated gas pressure of one gas storage means that is supplying the gas is less than a predetermined threshold among the plurality of gas storage means. 3. The gas supply apparatus according to claim 2, wherein the supply control is performed so that the gas is supplied from another gas storage means instead of the storage means.   4. The gas supply device according to claim 2, wherein the supply control unit includes a plurality of open / close valves that respectively correspond to the plurality of gas storage units and that can be opened / closed independently of each other. The gas supply path includes a plurality of branches connected to the plurality of gas storage means and a main body formed by synthesizing the plurality of branches. , Further comprising measuring means for measuring at least one parameter of the pressure and flow rate of the gas in the main body ,
The supply control means includes a gas storage means for supplying the gas in order of the detected or estimated gas pressure among the gas storage means when the measured parameter falls below a predetermined threshold. The gas supply device according to any one of claims 2 to 4, wherein the gas supply device is switched. A current measuring means for measuring an output current output by power generation of a fuel cell that generates power using the gas as a fuel;
The gas supply device according to any one of claims 1 to 5, wherein the gas pressure estimating means estimates the gas pressure based on the measured output current. Gas consumption calculation means for calculating gas consumption from the measured output current is further provided,
The gas supply device according to claim 6, wherein the gas pressure estimation unit estimates the gas pressure based on the calculated gas consumption.   When the abnormality is detected, the gas pressure estimation unit estimates the gas pressure based on a past gas pressure detected by the gas pressure detection unit before the abnormality is detected. The gas supply device according to any one of claims 1 to 7. A plurality of gas storage means for storing gas,
A gas pressure acquisition means for detecting or estimating a gas pressure caused by the gas in the gas storage means;
The gas supply path includes a plurality of branches connected to the plurality of gas storage means and a main body formed by synthesizing the plurality of branches. Measuring means for measuring at least one parameter of the pressure and flow rate of the gas in the main body ;
When the measured parameter falls below a predetermined threshold, the supply control is performed so as to switch the gas storage means for supplying the gas in order of the detected or estimated gas pressure among the plurality of gas storage means. A gas supply apparatus comprising: a supply control means for performing

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