Hydrogen gas supply method and hydrogen gas supply system

Abstract

To provide a hydrogen gas supply method and hydrogen gas supply system that can stably compress hydrogen regardless of whether the pressure is low or high and has excellent reliability. [Solution] A hydrogen gas supply method and supply system characterized in that, when hydrogen gas is supplied in accordance with the required pressure of the supply destination, as the required pressure changes from a low-pressure region to a high-pressure region, when the required pressure is in the low-pressure region, the supplied hydrogen gas is compressed at low pressure by a piston crank type compressor 1, and when the required pressure is in the high-pressure region, the supplied hydrogen gas is compressed at high pressure by a hydraulic compressor or a diaphragm type compressor 2.

Description

[Technical field]

[0001] The present invention relates to a hydrogen gas supply method and a hydrogen gas supply system, and more particularly to a hydrogen gas supply method and a hydrogen gas supply system that can stably compress hydrogen regardless of whether it is at low pressure or high pressure, and can satisfy customers' requests for rapid hydrogen filling. [Background technology]

[0002] In recent years, the development of fuel cell vehicles (FCVs), which use hydrogen gas as a power source, has progressed and is approaching the stage of practical application. Hydrogen gas is supplied to the hydrogen tank of a fuel cell vehicle at a hydrogen filling station, just as gasoline is supplied to a gasoline vehicle at a gas station.

[0003] Some hydrogen stations are on-site type, which are equipped with hydrogen production equipment and supply hydrogen produced by that equipment, but in order to reduce equipment costs, there are also off-site type hydrogen stations that use a cardle containing multiple gas containers (red) as the hydrogen supply source, which produces hydrogen outside the facility.

[0004] Patent Document 1 discloses a method in which, when producing high-pressure hydrogen gas, a hydraulic booster type compressor is used to boost the pressure to, for example, more than 82 MPa and store the pressure in a pressure accumulator, and, when producing medium-pressure hydrogen gas, a hydraulic booster type compressor is used to boost the pressure to, for example, 40 MPa and store the pressure in a pressure accumulator for use. However, hydraulic compressors are mechanisms that drive pistons using the hydraulic force of hydraulic oil, and due to restrictions such as sealing of hydraulic oil, the maximum number of cycles is smaller than that of piston crank compressors that have a crank mechanism. Therefore, compared to the piston crank type, there is a drawback in that the flow rate per compressor is smaller when increasing pressure from low to high.

[0005] Patent Document 2 discloses a method of five-stage compression using a crank-type compressor. Specifically, the compressor has cylinders extending radially around a crank-type rotary drive unit, and each cylinder is equipped with a piston. The five-stage compression increases the pressure from 0.6 MPa to 145.8 MPa. The piston crank type can compress a large flow rate from low pressure because it can handle a large number of cycles. Hydrogen stations use ultra-high pressure compression of over 80 MPa.

[0006] Patent Document 3 also uses a crank-type compressor at high pressures of 50 MPa or more, and in this type of hydrogen station, a crank-type compressor is sometimes used even at high pressures of 50 MPa or more. However, according to the inventors' investigations, there are concerns that ultra-high pressure compression may result in shorter life spans and reduced reliability of wear parts compared to low pressure compression. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] JP 2021-139378 A [Patent Document 2] JP 2016-183684 A [Patent Document 3] JP 2023-67967 A Summary of the Invention [Problem to be solved by the invention]

[0008] Therefore, an object of the present invention is to provide a hydrogen gas supply method and hydrogen gas supply system that can stably compress hydrogen regardless of whether it is at low pressure or high pressure and is highly reliable. Further objects of the present invention will become apparent from the following description. [Means for solving the problem]

[0009] The above problems are solved by the following inventions.

[0010] 1. When hydrogen gas is supplied according to the required pressure of the supply destination, in the process of the required pressure changing from a low pressure region to a high pressure region, In the case of the low pressure region, the supplied hydrogen gas is compressed at low pressure by a piston crank compressor, In the case of the high pressure region, the supplied hydrogen gas is compressed to a high pressure by a hydraulic compressor or a diaphragm compressor. A method for supplying hydrogen gas, comprising the steps of: The piston crank compressor and the hydraulic compressor or diaphragm compressor are mounted together and share common auxiliary equipment to form a unit of a size that can be fitted on the same skid. A method for supplying hydrogen gas comprising the steps of: 2. When hydrogen gas is supplied according to the required pressure of the supply destination, in the process of the required pressure changing from a low pressure region to a high pressure region, In the case of the low pressure region, the supplied hydrogen gas is compressed at low pressure by a piston crank compressor, In the case of the high pressure region, the supplied hydrogen gas is compressed to a high pressure by a hydraulic compressor or a diaphragm compressor. A method for supplying hydrogen gas, comprising the steps of: A method for supplying hydrogen gas, characterized in that the piston crank type compressor and the hydraulic compressor or the diaphragm type compressor share a single electric motor. 3. A clutch is provided to control ON / OFF of the drive of the hydraulic compressor or diaphragm compressor. The above-mentioned 2 The method for supplying hydrogen gas described above. 4. The hydrogen gas is supplied to a pressure accumulator or a hydrogen storage tank in a mobile vehicle at a hydrogen station. 1, 2 or 3 The method for supplying hydrogen gas described above. 5. The method of filling the hydrogen storage tank is a direct filling method from the compressor or a differential pressure filling method from the pressure accumulator, or both the direct filling method and the differential pressure filling method. 4 The method for supplying hydrogen gas described above. 6. The low pressure region of the required pressure of the supply destination is a region in which the upper limit is any value between 40 and 50 MPa, and the high pressure region is a region that is greater than any value of the upper limit of the low pressure region and is equal to or less than 100 MPa. 1, 2 or 3 The method for supplying hydrogen gas described above. 7. The piston crank compressor and the hydraulic compressor or the diaphragm compressor are integrally mounted and share common auxiliary equipment to form a unit of a size that can be accommodated on the same skid. 2 or 3 The method for supplying hydrogen gas described above. 8. The above Supply destination The hydrogen gas flow rate that can be supplied to is 400 Nm 3 / Hr~1200Nm 3 / Hr 1, 2 or 3 The method for supplying hydrogen gas described above. 9. A hydrogen gas supply system that selectively uses compressors for compressing hydrogen gas in a low pressure region and a high pressure region as the required pressure changes from a low pressure region to a high pressure region when supplying hydrogen gas according to the required pressure of a supply destination, In the case of the low pressure region, the supplied hydrogen gas is compressed at low pressure by a piston crank compressor, In the case of the high pressure region, the supplied hydrogen gas is compressed to a high pressure by a hydraulic compressor or a diaphragm compressor. A hydrogen gas supply system, comprising: The piston crank compressor and the hydraulic compressor or diaphragm compressor are mounted together and common auxiliary equipment is shared to form a compressor unit of a size that can be fitted on the same skid. A hydrogen gas supply system comprising: 10. A hydrogen gas supply system that selectively uses compressors for compressing hydrogen gas in a low pressure region and a high pressure region as the required pressure changes from a low pressure region to a high pressure region when supplying hydrogen gas according to the required pressure of a supply destination, In the case of the low pressure region, the supplied hydrogen gas is compressed at low pressure by a piston crank compressor, In the case of the high pressure region, the supplied hydrogen gas is compressed to a high pressure by a hydraulic compressor or a diaphragm compressor. A hydrogen gas supply system, comprising: The piston crank compressor and the hydraulic compressor or the diaphragm compressor share a common motor. A hydrogen gas supply system comprising: 11. A clutch is provided to control ON / OFF of the drive of the hydraulic compressor or diaphragm compressor. The above-mentioned 10 The hydrogen gas supply system described herein. 12. The hydrogen gas is supplied to a hydrogen storage tank in a hydrogen station or a hydrogen storage tank in a mobile vehicle by the compressor. 9, 10 or 11 The hydrogen gas supply system described herein. 13. The method of filling the hydrogen storage tank is a direct filling method from the compressor, a differential pressure filling method via the pressure accumulator, or a combination of the direct filling method and the differential pressure filling method. 12 The hydrogen gas supply system described herein. 14. The low pressure region of the required pressure of the supply destination is a region in which the upper limit is any value between 40 and 50 MPa, and the high pressure region is a region that is greater than any value of the upper limit of the low pressure region and is equal to or less than 100 MPa. 9, 10 or 11 The hydrogen gas supply system described herein. 15. The piston crank compressor and the hydraulic compressor or diaphragm compressor are mounted together and common auxiliary equipment is shared to form a compressor unit of a size that can be fitted on the same skid. The above-mentioned 10 or 11 The hydrogen gas supply system described herein. 16. The above Supply destination The hydrogen gas flow rate that can be supplied to is 400 Nm 3 / Hr~1200Nm 3 / Hr 9, 10 or 11 The hydrogen gas supply system described herein. 17. a motor pulley (102) provided on a drive shaft (101) of the electric motor (100); a piston crank compressor pulley (103) provided on a piston crank compressor side drive shaft (107) of the piston crank compressor (1); a hydraulic compressor pulley (105) provided on a hydraulic compressor-side drive shaft (108) of the hydraulic compressor (2), The motor pulley (102) and the piston crank compressor pulley (103) are rotatably connected to each other via a piston crank compressor belt (104). The motor pulley (102) and the hydraulic compressor pulley (105) are rotatably connected to each other via a hydraulic compressor belt (106). The piston crank compressor (1) is structured so that the rotation of a drive shaft by the drive of an electric motor is converted into linear reciprocating motion of a piston via a crankshaft, and compresses hydrogen gas filled above the piston in a cylinder. The hydraulic compressor (2) rotates the drive shaft driven by the electric motor, The hydraulic pressure generated by driving the hydraulic pump is converted into reciprocating motion of the piston. The hydrogen gas filled in the cylinder is compressed by the reciprocating motion of the piston. 9, 10 or 11 The hydrogen gas supply system described herein. 18. A hydrogen gas supply system that selectively uses compressors for compressing hydrogen gas in a low pressure region and a high pressure region as the required pressure changes from a low pressure region to a high pressure region when supplying hydrogen gas according to the required pressure of a supply destination, In the case of the low pressure region, the supplied hydrogen gas is compressed at low pressure by a piston crank compressor, In the case of the high pressure region, the supplied hydrogen gas is compressed to a high pressure by a hydraulic compressor or a diaphragm compressor, a piping system (110) that leads to a suction side of the hydraulic compressor (2) that compresses high pressure hydrogen via low pressure compression of the piston crank compressor (1) and leads to the hydraulic compressor (2); and a branch piping system (111) that bypasses the hydraulic compressor (2) and leads to a discharge side of the hydraulic compressor (2) without passing through the piston crank compressor (1) and entering the suction side of the hydraulic compressor (2), a control valve (112) for controlling opening and closing of the branch piping system (111); a clutch (109) for disconnecting the driving force of the electric motor (105) of the hydraulic compressor (2) from a drive shaft (108) of the hydraulic compressor (2); When the required pressure of the hydrogen storage tank is equal to or lower than a set value, the clutch (109) is disengaged and the control valve (112) is opened. A hydrogen gas supply system characterized in that, when the required pressure of the hydrogen storage tank becomes greater than the set value, the clutch (109) is engaged and the control valve (112) is closed. Effect of the Invention

[0011] According to the present invention, it is possible to provide a hydrogen gas supply method and a hydrogen gas supply system that can stably compress hydrogen regardless of whether the pressure is low or high and that are highly reliable.

[0012] Furthermore, according to the present invention, it is possible to provide a hydrogen gas supply method and a hydrogen gas supply system that enable stable filling of large volumes of hydrogen at hydrogen stations and that also provides excellent customer satisfaction. [Brief description of the drawings]

[0013] [Figure 1] FIG. 1 is a schematic side view showing an example of a hydrogen station to which the present invention is preferably applied, showing a direct charging system. [Diagram 2] FIG. 1 is a schematic side view showing another example of a hydrogen station to which the present invention is preferably applied, showing a differential pressure filling method. [Diagram 3] FIG. 1 is a schematic cross-sectional view showing an example of a piston crank compressor. [Figure 4] FIG. 1 is a schematic cross-sectional view showing an example of a hydraulic compressor. [Diagram 5] Schematic cross-sectional view showing an example of a diaphragm compressor. [Figure 6] FIG. 1 is a diagram illustrating an embodiment in which a motor is shared between a low-pressure hydrogen compressor and a high-pressure hydrogen compressor. [Figure 7] FIG. 1 is a diagram illustrating an embodiment in which a motor is shared between a low-pressure hydrogen compressor and a high-pressure hydrogen compressor. [Figure 8] FIG. 1 is a diagram showing an example of a control flow for starting a compressor in a hydrogen gas supply system according to the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] Preferred embodiments of the present invention will now be described. 1 and 2 are schematic side views showing an example of a hydrogen station to which the present invention is preferably applied. The example in FIG. 1 shows a direct filling method, and the example in FIG. 2 shows a differential pressure filling method.

[0015] Explaining based on Figures 1 and 2, the compressor comprises a piston crank type compressor (in the following description, may be referred to as a low-pressure hydrogen compressor) 1 and a hydraulic compressor (in the following description, may be referred to as a high-pressure hydrogen compressor) 2.

[0016] FIG. 1 shows an example of a direct filling method in which hydrogen gas produced by compression using a low-pressure hydrogen compressor 1 and a high-pressure hydrogen compressor 2 is filled into a hydrogen storage tank of a mobile object 4 via a dispenser 3.

[0017] FIG. 2 shows an example of a differential pressure filling method in which hydrogen gas produced by compression using a compressor is first supplied to a pressure accumulator 5, and then filled from the pressure accumulator 5 into a hydrogen storage tank of a mobile object 4 via a dispenser 3.

[0018] As shown in FIGS. 1 and 2, hydrogen gas supplied from a compressor is supplied to a pressure accumulator 5 in a hydrogen station or a hydrogen storage tank in a mobile object 4. Hydrogen gas can be filled into the hydrogen storage tank of the mobile object 4 by a direct filling method in which hydrogen is filled from a compressor via a dispenser 3 as shown in FIG. 1, or a differential pressure filling method in which hydrogen is supplied from a compressor to a pressure accumulator 5 as shown in FIG. 2 and then filled from the pressure accumulator 5 via a dispenser 3, or a combination of the direct filling method and the differential pressure filling method.

[0019] In this embodiment, an example is shown in which hydrogen gas, which serves as fuel, is supplied from a compressor to the destination, which is a pressure accumulator 5 or a hydrogen storage tank of a mobile object 4, at a hydrogen station. However, this is not limited to this, and the destination of the hydrogen gas is not limited to a hydrogen station. The hydrogen gas can also be compressed and supplied to a storage tank for transporting hydrogen. Hereinafter, the hydrogen gas supply method and system of the present invention will be described taking as an example a case where the destination of the supply of hydrogen gas as fuel is a hydrogen storage tank.

[0020] In the hydrogen gas supply method and system of the present invention, when the hydrogen gas pressure in the hydrogen storage tank is within the low pressure region, the piston crank compressor is driven to produce low-pressure compressed hydrogen and supply it to the hydrogen storage tank. Next, when the hydrogen gas pressure in the hydrogen storage tank enters a high pressure region, the hydraulic compressor or diaphragm compressor is driven to supply the produced high-pressure compressed hydrogen to the hydrogen storage tank.

[0021] In other words, depending on the required pressure of the hydrogen storage tank, when the required pressure is in the low pressure range, the piston crank type compressor is driven to supply compressed hydrogen gas, and when the required pressure reaches the high pressure range, the piston crank type compressor is driven to introduce the compressed hydrogen gas into the hydraulic compressor, and the hydraulic compressor is driven to supply the highly compressed hydrogen gas to the hydrogen storage tank.

[0022] The piston crank compressor 1 may have a plurality of compression stages, and preferably has, for example, three or four stages. The hydraulic compressor 2 may be a single stage or a two stage compressor. The total number of stages in the compressor including low pressure compression and high pressure compression may be five stages or about six to eight stages.

[0023] In the present invention, the low pressure region of the hydrogen gas pressure in the hydrogen storage tank is preferably a region with an upper limit of 40 to 50 MPa, and the high pressure region of the hydrogen gas pressure in the hydrogen storage tank is preferably a region greater than the upper limit of the low pressure region and less than 100 MPa. In this embodiment, the low pressure region has an upper limit of any value in the range of 40 to 50 MPa, and the high pressure region has an upper limit of up to 100 MPa, with a lower limit greater than any value of the upper limit of the low pressure region.

[0024] The gas pressure of the low-pressure hydrogen compressor 1 is in the range of 0.6 to 50 MPa, and the upper limit of the gas pressure of the high-pressure hydrogen compressor 2 is in the range of 100 MPa. Since the low-pressure hydrogen compressor 1 boosts the gas pressure in multiple stages as described above, it is possible to boost the gas pressure to any desired level by designing the boost ratio according to the number of stages. In this embodiment, the high-pressure hydrogen compressor 2 is a compressor for further boosting and supplying hydrogen when the pressure supplied by the low-pressure hydrogen compressor 1 is insufficient, for example, when the required pressure of the supply destination is in the high-pressure region. Therefore, the lower limit of the gas pressure of the high-pressure hydrogen compressor 2 is variable depending on the upper limit of the low-pressure hydrogen compressor 1.

[0025] The hydrogen gas flow rate that can be supplied to the hydrogen storage tank is 400 to 1200 Nm3 under standard conditions for the entire compressor.3 / Hr, which is a large flow rate at a practical level, which is a feature of the present invention.

[0026] Hydrogen to be compressed is usually brought to the hydrogen station in a curdle (a combination of hydrogen produced outside and multiple gas containers (red)). In addition to curdles, hydrogen may be supplied to the hydrogen station by pipeline.

[0027] Hydrogen is produced outside and brought to the hydrogen station in gaseous form, but it may be liquefied hydrogen. A hydrogen production device may be installed at the hydrogen station and hydrogen produced by the device may be used. Examples of hydrogen production devices include a device that produces hydrogen gas by installing a water electrolyzer and using an external power source, a hydrocarbon fuel cracking device, and a device that produces hydrogen gas by installing a liquefied hydrogen storage container filled with liquefied hydrogen and using a vaporizer.

[0028] In the hydrogen gas supply method and system of the present invention, the mobile object 4 may be a fuel cell vehicle or a ship that uses hydrogen as fuel. The present invention is suitable for large-capacity tanks in buses and trucks because it can supply a large flow rate of hydrogen gas.

[0029] Furthermore, the hydrogen gas supply system realizing the hydrogen gas supply method of the present invention is sized to fit on the same skid, as will be described in detail later. The size that fits on the same skid is, for example, a size that fits in a 20 ft container, specifically, the floor area of ​​the inside dimensions of a 20 ft container, but is not limited to this. The hydrogen station in which the present invention is installed is not limited to a land-based one, but may be an offshore one, and may be a fixed type or a mobile type.

[0030] FIG. 3 is a schematic cross-sectional view showing an example of a piston crank type compressor. In Fig. 3, a piston 11 is provided inside a cylinder 10, and a piston ring 12 is provided to prevent leakage from the outer periphery of the piston 11 to some extent. A plurality of piston rings 12 can be provided. In the example shown, two rings are provided. The lower part of the piston 11 is supported by a piston rod 13. The piston rod 13 is connected to a crankshaft 15 via a connecting rod 14.

[0031] The crankshaft 15 is rotatably connected to a compressor motor (not shown), and the rotation of the motor rotates the crankshaft 15, which converts the motion of the piston rod 13 into linear reciprocating motion, causing it to move up and down.

[0032] When the crankshaft 15 rotates, the piston rod 13 moves up and down, and the piston 11 moves up and down accordingly, so that the hydrogen gas filled above the piston 11 is compressed.

[0033] FIG. 4 is a schematic cross-sectional view showing an example of a hydraulic compressor. 4, pressure of oil working fluid 17 is applied from below a piston 11 equipped with a piston seal 16 provided in a cylinder 10. The oil working fluid 17 is sent from a hydraulic pump (not shown), and the piston 11 is pushed upward by the pump pressure of the hydraulic pump, compressing the hydrogen gas filled above the piston 11 in the cylinder 10. The mechanical drive described above has no oil working fluid and no object for leakage into the cylinder 10, so there is no risk of leakage from the piston ring 12 shown in FIG. 3. As a result, the load is not as large as in the hydraulic system, so the piston speed can be increased. On the other hand, in the case of the hydraulic system, it is necessary to prevent leakage of the oil working fluid 17 into the process side, so it is preferable to select a piston seal 16 with high sealing properties. As a result, it is preferable to keep the piston speed low to prevent wear and damage to the piston seal 16.

[0034] FIG. 5 is a schematic cross-sectional view showing an example of a diaphragm compressor. In FIG. 5, the piston rod 13 supporting the diaphragm 18 is caused to reciprocate (move up and down) to cause the diaphragm 18 to reciprocate (move up and down), thereby compressing the hydrogen gas filled above the diaphragm 18 inside the cylinder 10. This compressor compresses by moving a metal film called a diaphragm up and down to change the volume. Since there is no piston, there are no sliding parts, and it has the advantage of not having a lifespan due to wear. On the other hand, the diaphragm type compressor has a limited fatigue life because the volume changes due to the elastic deformation of the diaphragm 18.

[0035] In the present invention, a booster type hydraulic compressor that does not use a hydraulic pump can also be used. For example, this is a modification of the hydraulic pump type, in which the pressure of an oil working fluid pressurized by compressed air is applied from below a piston to reciprocate the piston, compressing the hydrogen gas filled above the piston in the cylinder.

[0036] The present invention is characterized in that low pressure compression and high pressure compression are performed by different types of compressors. Hydraulic compressors have a mechanism that drives pistons using the hydraulic force of hydraulic oil, and due to restrictions such as sealing of hydraulic oil, the maximum number of cycles is smaller than that of piston crank compressors with a crank mechanism. Therefore, compared to piston crank types, they have the characteristic of having a smaller flow rate per compressor when increasing pressure from low to high. However, the piston crank type can compress a large flow rate when compressing from a low pressure because it can have a large number of cycles.

[0037] At hydrogen stations, ultra-high pressure compression of over 80 MPa is achieved using a piston crank compressor. However, there are concerns that piston crank compressors may experience reduced life spans and reduced reliability of wear parts when used at high pressures of 50 MPa or more compared to low pressures of 50 MPa or less.In contrast, hydraulic compressors have strengths in the high and ultra-high pressure ranges. Therefore, by taking advantage of the characteristics of both, and placing a crank-type compressor in the front stage and a hydraulic compressor or diaphragm-type compressor, etc. in the rear stage, it is possible to provide a hydrogen gas supply method and system that has a high flow rate and is highly reliable and easy to use.

[0038] Next, an embodiment in which an electric motor is shared between a low-pressure hydrogen compressor (piston crank type compressor) and a high-pressure hydrogen compressor (hydraulic compressor) will be described with reference to Figs. 6 and 7.

[0039] As shown in Figures 6 and 7, an electric motor pulley 102 is provided on a drive shaft 101 of an electric motor 100, and a low-pressure hydrogen compressor pulley (pulley for a piston crank compressor) 103 and the electric motor pulley 102 provided on the drive shaft 101 are rotatably connected to a low-pressure hydrogen compressor side drive shaft (piston crank compressor side drive shaft) 107 via a low-pressure hydrogen compressor belt (piston crank compressor belt) 104, and a high-pressure hydrogen compressor pulley (pulley for a hydraulic compressor) 105 and the electric motor pulley 102 provided on the drive shaft 101 are rotatably connected to a high-pressure hydrogen compressor side drive shaft (hydraulic compressor side drive shaft) 108 via a high-pressure hydrogen compressor belt (hydraulic compressor belt) 106. In the illustrated example, the low-pressure hydrogen compressor 1 performs four-stage compression, but in this embodiment, although not shown, a return pipe for adjusting the hydrogen gas flow rate from each stage of the low-pressure hydrogen compressor 1 can also be provided. The high-pressure hydrogen compressor 2 can also be provided with a return pipe for adjusting the hydrogen gas flow rate.

[0040] The high-pressure hydrogen compressor side drive shaft 108 is provided with a clutch 109 that enables disconnection of the driving force of the electric motor 100. In other words, the driving force of the electric motor 100 can be ON-OFF controlled by the clutch 109.

[0041] The hydrogen passes through the low-pressure compression of the low-pressure hydrogen compressor 1 and reaches a piping system 110 on the suction side of the high-pressure hydrogen compressor 2. In this embodiment, a branch piping system 111 is provided which passes through the low-pressure compression of the low-pressure hydrogen compressor 1 and bypasses the high-pressure hydrogen compressor 2 to reach the discharge side of the high-pressure hydrogen compressor 2 without entering the suction side of the high-pressure hydrogen compressor 2. The branch piping system 111 is provided with a control valve 112 which controls opening and closing.

[0042] A pressure sensor 113 is provided near the hydrogen gas discharge portion of the compressor so as to be able to detect the discharge pressure.

[0043] 6 shows a state in which the clutch 109 is engaged, and when the electric motor 100 is driven, the rotational drive of the drive shaft 101 rotates the low-pressure hydrogen compressor side drive shaft 107, which is converted into linear reciprocating motion of the piston via the crankshaft, compressing the hydrogen gas filled above the piston in the cylinder. At this time, since the control valve 112 provided in the branch piping system 111 is closed, the hydrogen gas compressed by the low-pressure hydrogen compressor 1 is introduced into the piping system 110 leading to the high-pressure hydrogen compressor 2. Since the clutch 109 is engaged, the high-pressure hydrogen compressor 2 rotates the high-pressure hydrogen compressor side drive shaft 108 by the rotational drive of the drive shaft 101 of the electric motor 100, and the high-pressure hydrogen gas compressed by the high-pressure hydrogen compressor 2 can be discharged.

[0044] 7 shows a state in which the clutch 109 is disengaged, and when the electric motor 100 is driven, the rotational drive of the drive shaft 101 rotates the low-pressure hydrogen compressor side drive shaft 107, which is converted into linear reciprocating motion of the piston via the crankshaft, compressing the hydrogen gas filled above the piston in the cylinder. At this time, since the control valve 112 provided in the branch piping system 111 is open, the hydrogen gas compressed by the low-pressure hydrogen compressor 1 does not enter the piping system 110 leading to the high-pressure hydrogen compressor 2, but bypasses the high-pressure hydrogen compressor 2 and is introduced into the branch piping system 111, and reaches the line on the discharge side of the high-pressure hydrogen compressor 2. In this manner, the low-pressure hydrogen gas compressed by the low-pressure hydrogen compressor 1 can be discharged.

[0045] As described above, the electric motor 100 can be shared by both the low-pressure hydrogen compressor 1 and the high-pressure hydrogen compressor 2. This eliminates the need for an electric motor in each compressor, thereby reducing installation space and simplifying control, thereby reducing the control panel and electrical / control wiring.

[0046] Furthermore, by providing a clutch on the drive shaft of the high-pressure hydrogen compressor connected to the shared electric motor 100, when it is not necessary to drive the high-pressure hydrogen compressor, the connection can be disconnected by the clutch, so that the high-pressure hydrogen compressor cannot be driven. This shortens the actual operating time of the high-pressure hydrogen compressor, making it possible to extend the maintenance interval for the high-pressure hydrogen compressor, which in turn extends the service life of the high-pressure hydrogen compressor, thereby enabling the service life of the entire compressor to be extended to the service life of the low-pressure hydrogen compressor.

[0047] In addition, it is possible to share auxiliary equipment, including the cooling fans that cool the refrigerant used to cool the hydrogen gas used in the two types of compressors, making it possible to significantly reduce the installation space.

[0048] 6 and 7, the low-pressure hydrogen compressor 1 performs four-stage compression, and the high-pressure hydrogen compressor 2 performs one-stage compression. Although not shown, a mechanism is constructed that allows the hydrogen gas compressed in each stage to exchange heat with a refrigerant for cooling, and a mechanism is constructed that aggregates the refrigerant so that it is cooled by a single cooling fan (not shown). As a result, one cooling fan is shared by both the low-pressure hydrogen compressor 1 and the high-pressure hydrogen compressor 2, greatly reducing the installation space.

[0049] In this way, it is possible to significantly reduce the installation space, making it possible to create a compressor unit that fits into a 20-ft container.

[0050] The control flow of the system of this embodiment will be described with reference to Fig. 8. Here, the explanation will be given using an example of hydrogen supply by the direct filling method shown in Fig. 1.

[0051] First, when the dispenser is connected to a hydrogen storage tank of a mobile object, the required pressure of the hydrogen storage tank is detected (S1).

[0052] Next, it is determined whether the required pressure exceeds a predetermined set value (S2), where the predetermined set value is a pressure that has been set in advance.

[0053] In this embodiment, an example will be described in which hydrogen is compressed in a total of five stages, for example, using a four-stage low-pressure hydrogen compressor and one-stage high-pressure hydrogen compressor. In this case, if the high pressure discharge pressure is 90MPa and the suction pressure is 3MPa, a 30-fold boost is required to boost 3MPa to 90MPa. If the 30-fold boost is achieved in five stages, and each stage is boosted at the same pressure, the boost is 1.98 times per stage.

[0054] When the suction pressure is 3 MPa and the pressure is increased at a constant rate of 1.98 times, the first stage discharge pressure is approximately 5.9 MPa, the second stage discharge pressure is approximately 11.6 MPa, the third stage discharge pressure is approximately 22.9 MPa, the fourth stage discharge pressure is approximately 45.2 MPa, and the fifth stage discharge pressure is approximately 90 MPa.

[0055] In this way, by determining the suction pressure and the target discharge pressure at the design stage, the pressure boost ratio at each stage can be determined at the design stage. Therefore, by setting the set pressure to a value equal to or close to the discharge pressure of the final stage of the low-pressure hydrogen compressor 1 in the determined multiple stages, it is possible to determine whether or not to compress the hydrogen using the high-pressure hydrogen compressor 2 described below in relation to the required pressure (necessary pressure) of the supply destination of the compressor.

[0056] If the required pressure is equal to or lower than the predetermined set value (NO in S2), the required pressure is lower than the set value (set pressure), so the clutch 109 of the high-pressure hydrogen compressor 2 is disengaged (S3), the control valve 112 is opened (S4), the electric motor 100 is started, and the compressor is started (S7). In this case, since the clutch 109 is disengaged, only the low-pressure hydrogen compressor 1 is started, and the high-pressure hydrogen compressor 2 is not started.

[0057] On the other hand, if the required pressure is greater than the predetermined set value (YES in S2), the required pressure is higher than the set value (set pressure), so the clutch 109 of the high-pressure hydrogen compressor 2 is connected (S5), the control valve 112 is closed (S6), the electric motor 100 is started, and the compressor is started (S7). In this case, because the clutch 109 is connected, both the low-pressure hydrogen compressor 1 and the high-pressure hydrogen compressor 2 are started.

[0058] Next, when a predetermined condition for transmitting a stop signal is satisfied, a stop signal process is performed to transmit a stop signal (S8). The predetermined condition for the stop signal processing may be, for example, pressing an emergency stop button, completion of hydrogen supply, etc. In addition, a mechanical failure or the like may be detected, but is not limited to these, and is preferably determined taking safety and reliability into consideration.

[0059] Next, it is determined whether or not a stop signal is present (S9). If a stop signal is present, operation of the compressor is stopped (S10). If no stop signal is present, the process returns to detecting the required pressure (S1) and continues processing until a stop signal is present.

[0060] The above-described embodiment is merely an example, and is not intended to limit the scope of the invention. The invention can be embodied in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. Such embodiments and modifications are within the scope and spirit of the invention, and are included in the scope of the invention and its equivalents as set forth in the claims. [Explanation of symbols]

[0061] 1: Low pressure hydrogen compressor 2: High pressure hydrogen compressor 3: Dispenser 4: Moving object 5: Pressure accumulator 10: Cylinder 11: Piston 12: Piston rings 13: Piston rod 14:Joining rod 15: Crankshaft 16: Piston seal 17: Oil hydraulic fluid 18: Diaphragm 100: Electric motor 101: Drive shaft 102: Electric motor pulley 103: Pulley for low pressure hydrogen compressor (Pulley for piston crank type compressor) 104: Belt for low pressure hydrogen compressor (belt for piston crank compressor) 105: Pulley for high pressure hydrogen compressor (pulley for hydraulic compressor) 106: High pressure hydrogen compressor belt (hydraulic compressor belt) 107: Low pressure hydrogen compressor drive shaft (piston crank compressor drive shaft) 108: High pressure hydrogen compressor drive shaft (hydraulic compressor drive shaft) 109: Clutch 110: Piping system 111: Branch piping system 112: Control valve 113: Pressure sensor

Claims

1. When hydrogen gas is supplied according to the required pressure of the supply destination, in the process of the required pressure changing from a low pressure region to a high pressure region, In the case of the low pressure region, the supplied hydrogen gas is compressed at low pressure by a piston crank compressor, In the case of the high pressure region, the hydrogen gas to be supplied is compressed to a high pressure by a hydraulic compressor or a diaphragm compressor, A method for supplying hydrogen gas, characterized in that the piston crank type compressor and the hydraulic compressor or diaphragm type compressor are mounted together and common auxiliary equipment is shared to form a unit of a size that can fit on the same skid.

2. When hydrogen gas is supplied according to the required pressure of the supply destination, in the process of the required pressure changing from a low pressure region to a high pressure region, In the case of the low pressure region, the supplied hydrogen gas is compressed at low pressure by a piston crank compressor, In the case of the high pressure region, the hydrogen gas to be supplied is compressed to a high pressure by a hydraulic compressor or a diaphragm compressor, A method for supplying hydrogen gas, characterized in that the piston crank type compressor and the hydraulic compressor or the diaphragm type compressor share a single electric motor.

3. A method for supplying hydrogen gas as described in claim 2, characterized in that a clutch is provided for controlling the ON-OFF operation of the hydraulic compressor or diaphragm compressor.

4. 4. The method for supplying hydrogen gas according to claim 1, 2 or 3, wherein the destination of the supply of hydrogen gas from the compressor is a pressure accumulator in a hydrogen station or a hydrogen storage tank in a mobile body.

5. 5. The method for supplying hydrogen gas according to claim 4, wherein the method for filling the hydrogen storage tank is a direct filling method from the compressor or a differential pressure filling method from the accumulator, or both the direct filling method and the differential pressure filling method.

6. 4. The method for supplying hydrogen gas according to claim 1, 2 or 3, characterized in that the low-pressure region of the required pressure at the supply destination is a region having an upper limit value of any value between 40 and 50 MPa, and the high-pressure region is a region greater than the upper limit value of the low-pressure region and not exceeding 100 MPa.

7. A hydrogen gas supply method as described in claim 2 or 3, characterized in that the piston crank type compressor and the hydraulic compressor or diaphragm type compressor are mounted together and common auxiliary equipment is shared to form a unit of a size that can fit on the same skid.

8. The flow rate of hydrogen gas that can be supplied to the supply destination is 400 Nm ３ / Hr~1200Nm ３ 4. The method for supplying hydrogen gas according to claim 1, 2 or 3, wherein the hydrogen gas supply rate is 1 / Hr.

9. A hydrogen gas supply system that selectively uses compressors for compressing hydrogen gas in a low pressure region and a high pressure region as the required pressure changes from a low pressure region to a high pressure region when supplying hydrogen gas according to the required pressure of a supply destination, In the case of the low pressure region, the supplied hydrogen gas is compressed at low pressure by a piston crank compressor, In the case of the high pressure region, the hydrogen gas supplied is compressed to a high pressure by a hydraulic compressor or a diaphragm compressor, A hydrogen gas supply system characterized in that the piston crank type compressor and the hydraulic compressor or diaphragm type compressor are mounted together and common auxiliary equipment is shared, forming a compressor unit of a size that can fit on the same skid.

10. A hydrogen gas supply system that selectively uses compressors for compressing hydrogen gas in a low pressure region and a high pressure region as the required pressure changes from a low pressure region to a high pressure region when supplying hydrogen gas according to the required pressure of a supply destination, In the case of the low pressure region, the supplied hydrogen gas is compressed at low pressure by a piston crank compressor, In the case of the high pressure region, the hydrogen gas supplied is compressed to a high pressure by a hydraulic compressor or a diaphragm compressor, A hydrogen gas supply system, characterized in that the piston crank type compressor and the hydraulic compressor or diaphragm type compressor share a single electric motor.

11. The hydrogen gas supply system according to claim 10, further comprising a clutch for controlling ON / OFF of the drive of the hydraulic compressor or the diaphragm compressor.

12. 12. The hydrogen gas supply system according to claim 9, 10 or 11, wherein the destination of the hydrogen gas supplied by the compressor is a pressure accumulator at a hydrogen station or a hydrogen storage tank in a mobile vehicle.

13. 13. The hydrogen gas supply system according to claim 12, characterized in that the method of filling the hydrogen storage tank is a direct filling method from the compressor, a differential pressure filling method via the accumulator, or a combination of the direct filling method and the differential pressure filling method.

14. A hydrogen gas supply system as described in claim 9, 10 or 11, characterized in that the low pressure region of the required pressure at the destination is a region where the upper limit value is any value between 40 and 50 MPa, and the high pressure region is a region that is greater than any value of the upper limit value of the low pressure region and is not more than 100 MPa.

15. A hydrogen gas supply system as described in claim 10 or 11, characterized in that the piston crank type compressor and the hydraulic compressor or diaphragm type compressor are mounted together and share common auxiliary equipment, forming a compressor unit of a size that can fit on the same skid.

16. The flow rate of hydrogen gas that can be supplied to the supply destination is 400 Nm ３ / Hr~1200Nm ３ 12. The hydrogen gas supply system according to claim 9, 10 or 11, characterized in that the hydrogen gas supply rate is 1 / Hr.

17. A motor pulley (102) provided on a drive shaft (101) of the electric motor (100); A piston crank compressor pulley (103) provided on a piston crank compressor side drive shaft (107) of the piston crank compressor (1); a hydraulic compressor pulley (105) provided on a hydraulic compressor side drive shaft (108) of the hydraulic compressor (2), The motor pulley (102) and the piston crank compressor pulley (103) are rotatably connected to each other via a piston crank compressor belt (104), The electric motor pulley (102) and the hydraulic compressor pulley (105) are rotatably connected via a hydraulic compressor belt (106), The piston crank compressor (1) has a structure in which the rotation of a drive shaft by the drive of an electric motor is converted into linear reciprocating motion of a piston via a crankshaft, and compresses hydrogen gas filled above the piston in a cylinder. The hydraulic compressor (2) is configured such that the rotation of the drive shaft by the drive of an electric motor is converted into reciprocating motion of a piston by the hydraulic pressure generated by driving a hydraulic pump, and the reciprocating motion of the piston compresses the hydrogen gas filled in the cylinder.

18. A hydrogen gas supply system that selectively uses compressors for compressing hydrogen gas in a low pressure region and a high pressure region as the required pressure changes from a low pressure region to a high pressure region when supplying hydrogen gas according to the required pressure of a supply destination, In the case of the low pressure region, the supplied hydrogen gas is compressed at low pressure by a piston crank compressor, In the case of the high pressure region, the supplied hydrogen gas is compressed to a high pressure by a hydraulic compressor or a diaphragm compressor, a piping system (110) that leads to the suction side of the hydraulic compressor (2) that compresses high pressure hydrogen via the low pressure compression of the piston crank compressor (1) and leads to the hydraulic compressor (2); and a branch piping system (111) that leads to the discharge side of the hydraulic compressor (2) by bypassing the hydraulic compressor (2) via the piston crank compressor (1) without entering the suction side of the hydraulic compressor (2), A control valve (112) for controlling opening and closing is provided in the branch piping system (111); a clutch (109) for disconnecting the driving force of the electric motor (105) of the hydraulic compressor (2) from the drive shaft (108) of the hydraulic compressor (2); When the required pressure of the supply destination is equal to or lower than the set value, the clutch (109) is disengaged and the control valve (112) is opened; A hydrogen gas supply system, characterized in that when the required pressure at the supply destination becomes greater than the set value, the clutch (109) is engaged and the control valve (112) is closed.

Images