JP5919103B2 - High pressure gas system - Google Patents

Description

  The present invention relates to a high pressure gas system.

  2. Description of the Related Art Conventionally, for example, as a system using high-pressure gas, a plurality of fuel tanks connected in parallel to a fuel cell and a control device that controls opening and closing of the on-off valve of each fuel tank are provided. There is known a fuel supply device that prevents reverse pressure from acting on an on-off valve in a closed state by opening the on-off valve in ascending order of tank pressure (see, for example, Patent Document 1).

JP 2008-223784 A

  By the way, according to the fuel supply device according to the above prior art, it is necessary to provide a plurality of pressure sensors in order to detect the tank pressure of each fuel tank, which increases the cost required for the device configuration and increases the weight of the device. The problem arises.

  The present invention has been made in view of the above circumstances, and appropriately controls the opening and closing of shut-off valves of a plurality of high-pressure gas tanks connected to a gas supply target while preventing an increase in cost and weight required for the system configuration. The object is to provide a high-pressure gas system capable of this.

In order to solve the above problems and achieve the object, a high pressure gas system according to a first invention of the present invention includes a plurality of high pressure gas tanks (for example, the gas tank 12 in the embodiment) and the plurality of high pressure gas tanks. A high-pressure gas flow path (for example, high-pressure gas flow path 14 in the embodiment) for merging and supplying the gas supplied from the high-pressure gas tank, and each high-pressure gas tank and the high-pressure gas flow A shutoff valve (for example, the main stop valve 13 in the embodiment) that allows and shuts off the flow of the gas to and from the passage, and is provided for each of the high pressure gas tanks, and detects the temperature of the gas. A temperature sensor that outputs a temperature signal as a result (for example, temperature sensor 19 in the embodiment), and a control unit that can control the opening and closing of each shut-off valve in response to the temperature signal output from each temperature sensor ( For example, the electronic control device 20) according to the embodiment includes the electronic control device 20), and the control means opens the plurality of shut-off valves in response to the valve opening request, and then the temperature of any one of the temperature signals is predetermined. Another high-pressure gas tank other than the high-pressure gas tank provided with the temperature sensor that outputs the temperature signal when the temperature is exceeded or when the temperature increase rate of any one of the temperature signals exceeds a predetermined value Close all the shut-off valves.

  In the high pressure gas system according to the second aspect of the present invention, the control means closes the shutoff valve according to the temperature of any one of the temperature signals, and then receives a valve opening request again. The opening of the shut-off valve is prohibited.

A high-pressure gas system according to a third aspect of the present invention includes a plurality of high-pressure gas tanks (for example, the gas tank 12 in the embodiment) and a high-pressure gas that joins and supplies the gases supplied from the plurality of high-pressure gas tanks. A flow path (for example, the high-pressure gas flow path 14 in the embodiment) and each high-pressure gas tank is provided, and the flow of the gas between the high-pressure gas tank and the high-pressure gas flow path is allowed and blocked. A shut-off valve (for example, the main stop valve 13 in the embodiment) and a pressure sensor (for example, for implementation) that is provided in the high-pressure gas flow path and detects the pressure of the gas and outputs a pressure signal of the detection result High pressure sensor (P1) 17 in the form, medium pressure sensor (P2) 18), and flow rate grasping means for grasping the flow rate of the gas flowing through the high pressure gas flow path (for example, the electronic control device in the embodiment) 20) and Control means (for example, also serving as the electronic control unit 20 in the embodiment) capable of controlling the opening and closing of each shut-off valve in response to the pressure signal and the result of grasping the flow rate grasped by the flow rate grasping means; The control means opens a plurality of the shut-off valves in response to a valve opening request, and then a difference between the pressure of the pressure signal and the pressure obtained from the flow rate of the grasping result exceeds a predetermined value. In this case, even if a valve opening request is received again, the opening of all the shutoff valves is prohibited.

According to the high-pressure gas system of the first aspect of the present invention, when the high-pressure gas system is started up and the shut-off valve is opened with a pressure difference between the plurality of high-pressure gas tanks, The gas flows to the side. In this state, when the temperature of the gas in the low-pressure side high-pressure gas tank into which the gas flows or the rate of temperature increase exceeds a predetermined value, the inflow of the gas is stopped by closing the shutoff valve.
This prevents an excessive increase in the temperature of the gas in the high-pressure gas tank, keeps the gas temperature within a predetermined guaranteed temperature range, and ensures the desired reliability of the high-pressure gas system.

  In addition, a simple configuration in which each high-pressure gas tank has only a temperature sensor eliminates the need for, for example, a pressure sensor in each high-pressure gas tank, prevents an increase in the cost required for the device configuration, and increases the weight of the device. Can be prevented.

  According to the high pressure gas system of the second aspect of the present invention, after the shut-off valve is closed when the temperature exceeds a predetermined temperature or the rate of temperature increase exceeds a predetermined value, By prohibiting the opening of only a part of the shutoff valves in response to the valve opening request, the operation of the high pressure gas system can be continued by supplying the gas through the shutoff valves that are not prohibited to be opened.

In other words, if the gas flows from the high-pressure gas tank on the high-pressure side to the high-pressure gas tank on the low-pressure side in response to the valve opening request this time, and the gas temperature rises in the high-pressure gas tank on the low-pressure side, this high-pressure gas tank on the low-pressure side In response to the next request to open the valve, only the opening of the shutoff valve is permitted, and the high pressure gas tank on the high pressure side is prohibited from opening.
As a result, in response to the next valve opening request, it is possible to supply gas from the low pressure side high pressure gas tank while preventing the gas temperature from rising again in the low pressure side high pressure gas tank.

According to the high pressure gas system of the third aspect of the present invention, when the difference between the pressure indication value by the pressure signal and the estimated pressure value according to the flow rate exceeds a predetermined value, any of the shut-off valves Is abnormal, and it is determined that there is a pressure difference between the plurality of high-pressure gas tanks. By prohibiting the opening of the shut-off valve in response to the next valve opening request, the gas flows from the high pressure side to the low pressure side, and the temperature of the gas in the high pressure gas tank on the low pressure side is excessively increased. To prevent.
Thereby, the temperature of the gas can be kept within a predetermined guaranteed temperature range, and the desired reliability of the high-pressure gas system can be ensured.

1 is a configuration diagram of a high-pressure gas system according to an embodiment of the present invention. It is a flowchart which shows operation | movement of the high pressure gas system which concerns on embodiment of this invention. It is a graph which shows the change of the gas temperature of each gas tank in the high pressure gas system which concerns on embodiment of this invention. It is a graph which shows the change of the gas temperature difference between the two gas tanks in the high pressure gas system which concerns on embodiment of this invention. The operation of the high pressure gas system according to a modification of the embodiment of the present invention is a flow chart showing. It is a graph which shows the change of the instruction | indication value of pressure, and an estimated value in the high pressure gas system which concerns on the modification of embodiment of this invention.

  Hereinafter, a high-pressure gas system according to an embodiment of the present invention will be described with reference to the accompanying drawings.

  As shown in FIG. 1, for example, the high-pressure gas system 10 according to the present embodiment includes a fuel cell stack 11, a plurality of high-pressure gas tanks 12, a main stop valve 13 provided in each gas tank 12, and a high-pressure gas flow path. 14, a primary pressure reducing valve 15, an intermediate pressure device 16, a high pressure sensor (P1) 17, an intermediate pressure sensor (P2) 18, a temperature sensor 19 for detecting the gas temperature in each gas tank 12, and electronic control And an apparatus (ECU) 20.

A plurality of high-pressure gas tanks 12 (for example, the first gas tank 12 a and the second gas tank 12 b) store reaction gas supplied to the fuel cell stack 11.
The high-pressure gas flow path 14 includes, for example, a merging portion 14b that merges the flow paths 14a,..., 14a connected to the main stop valves 13, and combines the reaction gases supplied from all the gas tanks 12 to form a fuel cell. Flow to the stack 11.
The main stop valve 13 provided for each gas tank 12 allows and blocks the flow of the reaction gas between each gas tank 12 and the flow path 14a.

For example, the primary pressure reducing valve 15 is provided between the merging portion 14 b and the fuel cell stack 11 in the high-pressure gas flow path 14.
The intermediate pressure device 16 is provided, for example, between the primary pressure reducing valve 15 and the fuel cell stack 11 in the high pressure gas flow path 14.

For example, the high pressure sensor (P1) 17 is provided between the junction 14b and the primary pressure reducing valve 15 in the high pressure gas flow path 14, and detects and detects the pressure of the reaction gas flowing in the high pressure gas flow path 14. Output the resulting pressure signal.
The intermediate pressure sensor (P2) 18 is provided, for example, between the primary pressure reducing valve 15 and the intermediate pressure device 16 in the high pressure gas flow path 14, and detects the pressure of the reaction gas flowing through the high pressure gas flow path 14. And output the pressure signal of the detection result.

  The temperature sensor 19 (for example, the 1st temperature sensor 19a and the 2nd temperature sensor 19b) is provided with the thermistor etc., for example, detects the gas temperature in each gas tank 12, and outputs the temperature signal of a detection result.

  For example, the ECU 20 receives the temperature signal output from the temperature sensor 19 of each gas tank 12 and controls the opening and closing of each main stop valve 13.

  The high-pressure gas system 10 according to the present embodiment has the above-described configuration. Next, the operation of the high-pressure gas system 10 will be described.

First, processing for controlling the opening and closing of each main stop valve 13 by receiving a temperature signal output from the temperature sensor 19 of each gas tank 12 will be described below.
For example, in step S01 shown in FIG. 2, the main stop valve 13 of each gas tank 12 is opened in response to a valve opening request generated when the high-pressure gas system 10 is started, and the temperature sensors 19 are sequentially opened after the valve opening. Based on the output temperature signal, the gas temperature in each gas tank 12 is acquired.

Next, in step S02, whether or not the temperature increase rate of the gas temperature in at least one of the gas tanks 12 is greater than a predetermined increase rate (for example, 5 ° C./min), or at least one of the gas tanks 12. It is determined whether the gas temperature inside is higher than a predetermined temperature (for example, 85 ° C. or the like).
If this determination is “NO”, the flow proceeds to the end.
On the other hand, if the determination is “YES”, the flow proceeds to step S03.

In step S03, the main stop valves 13 of all the gas tanks 12 are closed.
Next, in step S04, the gas tank 12 that has been determined that the temperature increase rate of the gas temperature is greater than the predetermined increase rate or the gas temperature is higher than the predetermined temperature in the determination process of step S02 described above is the high-temperature side gas tank. 12, and the other gas tank 12 is a low-temperature side gas tank 12. Then, the valve opening request occurring in such next startup of the high pressure gas system 10, to allow the opening of the main valve 13 of the gas tank 12 of the Atsushi Ko side, the low-temperature side of the main stop valve of the gas tank 12 Prohibit valve opening 13 and proceed to the end.

For example, in response to a valve opening request generated at the time of starting the high-pressure gas system 10 or the like, after the time t0 when the opening of the main stop valve 13 of each gas tank 12 is instructed, an appropriate main stop valve 13 ( For example, when the valve opening delay or the valve opening failure of the main stop valve 13) of the second gas tank 12b including the second temperature sensor 19b occurs, this gas tank 12 and another gas tank in which the main stop valve 13 is normally opened 12 (for example, the main stop valve 13 of the 1st gas tank 12a provided with the 1st temperature sensor 19a) produces a pressure difference.
Then, according to this pressure difference, the reaction gas flows from the high pressure side to the low pressure side, and for example, as shown in FIG. 3, the gas temperature T1 output from the first temperature sensor 19a changes to a decreasing tendency. Along with this, the gas temperature T2 output from the second temperature sensor 19b changes to increase.

In this state, when the gas temperature T2 exceeds the predetermined temperature by the above-described processing of step S01 to step S04, or when the increase rate of the gas temperature T2 exceeds the predetermined increase rate, the main of all the gas tanks 12 The stop valve 13 is closed.
In response to a valve opening request that occurs at the next startup of the high-pressure gas system 10, the opening of the main stop valve 13 of the first gas tank 12a including the first temperature sensor 19a is prohibited , and the second temperature sensor 19b. The opening of the main stop valve 13 of the second gas tank 12b provided with is permitted .

  In step S03 described above, whether or not the temperature increase rate of the gas temperature in at least one of the gas tanks 12 is greater than a predetermined increase rate, or at least the gas temperature in any of the gas tanks 12 is higher than the predetermined temperature. However, the present invention is not limited to this. For example, in at least any one pair of the plurality of gas tanks 12, the increase rate of the temperature difference between the gas temperatures is a predetermined increase rate (for example, It may be determined whether it is greater than 5 ° C./min).

In this case, for example, as shown in FIG. 4, after the time t0 when the main stop valve 13 of each gas tank 12 is opened, from the gas temperature T1 output from the first temperature sensor 19a and the second temperature sensor 19b. When the temperature difference from the output gas temperature T2 (for example, temperature difference T2-T1) changes in an increasing tendency and this temperature difference exceeds a predetermined temperature difference, the main stop valves 13 of all the gas tanks 12 are The valve is closed.
Then, the valve opening request occurring in such next startup of the high pressure gas system 10, the opening of the main valve 13 of the first tank 12a with a first temperature sensor 19a that relatively gas temperature increases the Opening of the main stop valve 13 of the second gas tank 12b including the second temperature sensor 19b that is permitted and the gas temperature is relatively lowered is prohibited.

  As described above, according to the high-pressure gas system 10 according to the present embodiment, the fuel cell can be prevented from increasing in cost and weight required for the system configuration by a simple configuration in which each gas tank 12 includes only the temperature sensor 19. The opening and closing of the main stop valves 13 of the plurality of gas tanks 12 connected to the stack 11 can be appropriately controlled.

  That is, by closing the main stop valves 13 of all the gas tanks 12 when the gas temperature in any one of the gas tanks 12 exceeds a predetermined temperature, or when the rate of increase in gas temperature exceeds a predetermined rate of increase. The excessive increase in the gas temperature in the gas tank 12 can be prevented, the gas temperature can be kept within a predetermined guaranteed temperature range, and the desired reliability of the high-pressure gas system 10 can be ensured.

Further, for the next valve opening request, the main stop valve 13 of the gas tank 12 whose gas temperature has increased due to the present valve opening request, that is, the main stop valve that was normal without any valve opening delay or valve opening failure. Allow 13 to open. On the other hand, the opening of the main stop valve 13 in which valve opening delay or valve opening failure has occurred is prohibited.
Thus, the reaction gas can be supplied from the gas tank 12 to the fuel cell stack 11 while preventing the gas temperature from rising excessively again in the gas tank 12. Alternatively, in response to the next valve opening request, control may be performed so as not to permit the opening of all the main stop valves 13 so that the user of the high-pressure gas system 10 is prompted to perform maintenance.

  In the embodiment described above, the ECU 20 controls the opening and closing of each main stop valve 13 in response to the temperature signal output from the temperature sensor 19 of each gas tank 12, but is not limited to this. As in the modification of the embodiment, the opening and closing of each main stop valve 13 may be controlled by receiving a pressure signal output from the high pressure sensor (P1) 17 or the intermediate pressure sensor (P2) 18.

  In this modification, the ECU 20 detects the flow rate output from a flow rate sensor (not shown) that detects the flow rate of the reactive gas flowing from the gas tanks 12 toward the fuel cell stack 11 and flowing in the high-pressure gas flow path 14, for example. In response to the flow rate signal of the result, or the detection result signal output from each sensor (not shown) that detects the output current and output voltage of the fuel cell stack 11, it relates to the power generation amount of the fuel cell stack 11. Know the flow rate of the reaction gas.

  Then, the pressure of the reaction gas flowing through the high-pressure gas passage 14 is estimated based on the grasped flow rate of the reaction gas to generate an estimated value of the pressure, and the high-pressure sensor (P1) 17 or the intermediate-pressure sensor (P2). ) In response to the pressure signal output from 18, the pressure indication value is acquired, and the opening and closing of each main stop valve 13 is controlled according to the difference between the estimated pressure value and the indication value.

For example, the ECU 20 determines the estimated value P (MPa) of the pressure in the gas tank 12, the function F (x) (kg / m ³ ) of the density based on the pressure variable x, the capacity V (liter) of the gas tank 12, and the high-pressure gas. The pressure P0 (MPa) of the gas tank 12 at the time of starting the system 10, the power generation amount A (kWh) of the fuel cell stack 11, the coefficient B (kg) for converting the power generation amount into the consumption amount of the reaction gas, and the high pressure gas system The estimated pressure value is calculated based on the following equation (1) based on the purge amount C (kg) of the reaction gas from 10 to the outside.

Below, operation | movement of the high pressure gas system 10 which concerns on this modification is demonstrated.
For example, in step S11 shown in FIG. 5, the main stop valve 13 of each gas tank 12 is opened in response to a valve opening request generated at the time of starting the high pressure gas system 10, and the high pressure sensor (P1) 17 is opened after the valve opening. Alternatively, based on the pressure signal sequentially output from the intermediate pressure sensor (P2) 18, an indication value of the pressure of the reaction gas flowing through the high pressure gas flow path 14 is acquired.
Further, a flow rate signal of a flow rate detection result sequentially output from a flow rate sensor (not shown) that detects the flow rate of the reaction gas flowing in the high-pressure gas flow path 14, or the output current of the fuel cell stack 11 and Receiving the detection result signal sequentially output from each sensor (not shown) for detecting the output voltage, the power generation amount of the fuel cell stack 11 is grasped.

  Next, in step S12, the pressure of the reaction gas flowing in the high-pressure gas flow path 14 is estimated according to the flow rate of the reaction gas related to the grasped power generation amount of the fuel cell stack 11, and an estimated value of pressure is generated. .

Next, in step S13, it is determined whether or not the difference between the estimated pressure value and the indicated value (estimated value−indicated value) is greater than a predetermined value (for example, 5 MPa).
If this determination is “NO”, the flow proceeds to step S 14, in which it is determined that each main stop valve 13 is normal, and the flow proceeds to the end.
On the other hand, if this determination is “YES”, the flow proceeds to step S 15, and in this step S 15, at least one of the main stop valves 13 is abnormal, for example, a valve closing failure that causes an unintended valve closing state. Determine and proceed to step S16.

  And in step S16, with respect to the valve opening request | requirement which generate | occur | produces at the time of the next starting of the high pressure gas system 10, the valve opening of the main stop valves 13 of all the gas tanks 12 is prohibited, and it progresses to an end.

According to this modification, in response to a valve opening request generated at the next start-up of the high-pressure gas system 10, the reaction gas flows from the high-pressure side gas tank 12 to the low-pressure side gas tank 12, and the low-pressure side gas tank. The gas temperature in 12 is prevented from rising excessively.
Thereby, the gas temperature can be kept within a predetermined guaranteed temperature range, and the desired reliability of the high-pressure gas system 10 can be ensured.

For example, in response to a valve opening request generated at the time of starting the high pressure gas system 10 or during the operation of the high pressure gas system 10, there is a valve closing failure that is not intended for the main stop valve 13 of the appropriate gas tank 12. When this occurs, a pressure difference is generated between the gas tank 12 whose main stop valve 13 is poorly closed and the normal gas tank 12 whose main stop valve 13 is open as the reaction gas is consumed by the fuel cell stack 11. .
On the other hand, since a desired power generation amount is ensured in the fuel cell stack 11, a desired flow rate corresponding to the power generation amount of the fuel cell stack 11 is maintained for the reaction gas flowing in the high-pressure gas flow path 14. The
Accordingly, for example, as shown in FIG. 6, the indication value of the pressure of the reaction gas flowing through the high-pressure gas flow path 14 is estimated from the flow rate of the reaction gas corresponding to the amount of power generated by the fuel cell stack 11 Decreases compared to the value.

  In this state, if the difference between the estimated pressure value and the indicated value exceeds a predetermined value as a result of the processing in steps S11 to S16 described above, the main stop valve 13 of any gas tank 12 is abnormal. Determined. In response to a valve opening request that occurs at the next startup of the high-pressure gas system 10, the opening of the main stop valves 13 of all the gas tanks 12 is prohibited.

According to this modification, even when a pressure difference is generated between the plurality of gas tanks 12, by prohibiting the main stop valve 13 from opening in response to the next valve opening request, the low pressure is increased from the high pressure side. This prevents the reaction gas from flowing to the side and the gas temperature in the gas tank 12 on the low pressure side from rising excessively.
Thereby, the gas temperature can be kept within a predetermined guaranteed temperature range, and the desired reliability of the high-pressure gas system 10 can be ensured.

In the above-described embodiment, for example, when a pressure sensor for detecting the pressure in each gas tank 12 is provided, each gas tank 12 output from these pressure sensors is used instead of the temperature sensor 19 of each gas tank 12. The opening / closing of each main stop valve 13 may be controlled using a signal of the detection result of the internal pressure.
In this case, for example, in step S02 described above, at least the pressure increase rate of the pressure in the gas tank 12 is greater than a predetermined increase rate, or at least the pressure in the gas tank 12 is predetermined. It is determined whether or not it is higher than the pressure.

Further, in the modification of the embodiment described above, for example, when a pressure sensor for detecting the pressure in each gas tank 12 is provided, instead of the high pressure sensor (P1) 17 or the intermediate pressure sensor (P2) 18, these are used. The opening / closing of each main stop valve 13 may be controlled using a signal of the pressure detection result in each gas tank 12 output from the pressure sensor.
In this case, for example, in the above-described steps S11 to S13, it is determined whether or not the pressure difference between the gas tanks 12 of at least any combination is larger than a predetermined value (for example, 5 MPa).

It should be noted that the technical scope of the present invention is not limited to the above-described embodiment, and includes various modifications made to the above-described embodiment without departing from the spirit of the present invention. That is, the configuration of the above-described embodiment is merely an example, and can be changed as appropriate.
For example, the main stop valve 13 of the gas tank 12 having the highest gas temperature when the gas temperature decrease width or the temperature decrease rate in any of the gas tanks 12 into which gas flows in exceeds a predetermined value. May be closed. Even in this case, an excessive increase in the gas temperature can be prevented, the gas temperature can be kept within a predetermined guaranteed temperature range, and the desired reliability of the high-pressure gas system 10 can be ensured.

DESCRIPTION OF SYMBOLS 10 High pressure gas system 11 Fuel cell stack 12 Gas tank 13 Main stop valve 14 High pressure gas flow path 15 Primary pressure reducing valve 16 Medium pressure device 17 High pressure sensor (P1)
18 Medium pressure sensor (P2)
19 Temperature sensor 20 Electronic control unit (ECU)

Claims (3)

A plurality of high-pressure gas tanks;
A high-pressure gas flow path for merging and flowing gases supplied from the plurality of high-pressure gas tanks;
A shut-off valve that is provided for each of the high-pressure gas tanks and allows and shuts off the flow of the gas between each of the high-pressure gas tanks and the high-pressure gas flow path;
A temperature sensor that is provided for each of the high-pressure gas tanks, detects the temperature of the gas, and outputs a temperature signal as a detection result;
Control means that can control the opening and closing of each shut-off valve in response to the temperature signal output from each temperature sensor,
The control means includes
After opening a plurality of shut-off valves in response to a valve opening request, when the temperature of any of the temperature signals exceeds a predetermined temperature, or the rate of increase in the temperature of any of the temperature signals is a predetermined value A high-pressure gas system that closes all the shut-off valves of the other high-pressure gas tanks other than the high-pressure gas tank provided with the temperature sensor that outputs the temperature signal when the temperature is exceeded.   The control means prohibits the opening of the shut-off valve when the valve is requested to open again after the shut-off valve is closed according to the temperature of any one of the temperature signals. The high-pressure gas system according to claim 1. A plurality of high-pressure gas tanks;
A high-pressure gas flow path for merging and flowing gases supplied from the plurality of high-pressure gas tanks;
A shut-off valve that is provided for each of the high-pressure gas tanks and allows and shuts off the flow of the gas between each of the high-pressure gas tanks and the high-pressure gas flow path;
A pressure sensor provided in the high-pressure gas flow path for detecting the pressure of the gas and outputting a pressure signal as a detection result;
A flow rate grasping means for grasping a flow rate of the gas flowing through the high-pressure gas flow path;
Control means capable of controlling the opening and closing of each shut-off valve in response to the grasping result of the flow rate grasped by the pressure signal and the flow rate grasping means,
The control means includes
After opening a plurality of shut-off valves in response to a valve opening request, if the difference between the pressure of the pressure signal and the pressure obtained from the flow rate of the grasping result exceeds a predetermined value, it is opened again. A high-pressure gas system that prohibits the opening of all the shut-off valves even when a valve request is received.

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