WO2021027263A1

WO2021027263A1 - Electro-hydraulic driven piston-type hydrogen compressor and compression method

Info

Publication number: WO2021027263A1
Application number: PCT/CN2020/073090
Authority: WO
Inventors: 尹智
Original assignee: 尹智
Priority date: 2019-08-09
Filing date: 2020-01-20
Publication date: 2021-02-18
Also published as: CN114144584B; CN110296062A; CN114144584A

Abstract

An electro-hydraulic driven piston-type hydrogen compressor and compression method, comprising a hydraulic reversing system (1), a first two-stage compression cylinder (2), a second two-stage compression cylinder (3), a gas cooling device (4) and a gas pipeline (5), wherein the first two-stage compression cylinder (2) and the second two-stage compression cylinder (3) are arranged in series to achieve four-stage compression; the hydraulic reversing system (1) separately provides power for the first two-stage compression cylinder (2) and the second two-stage compression cylinder (3); and the gas cooling device (4) separately cools the two-stage compression of the first two-stage compression cylinder (2) and the second two-stage compression cylinder (3). The compressor implements the four-stage supercharged compression of hydrogen and solves the problem of compression heat dissipation.

Description

Electric hydraulic driven piston type hydrogen compressor and compression method

Technical field

The invention relates to the technical field of compressors, in particular to an electric hydraulic driven piston type hydrogen compressor and a compression method.

Background technique

In recent years, in order to reduce the carbon dioxide emitted by vehicles, the development of fuel cell electric vehicles and hydrogen-burning vehicles that use hydrogen such as hydrogen-engine vehicles as fuel has been popular. Hydrogen vehicles are generally equipped with hydrogen tanks filled with hydrogen as the hydrogen supply source. The hydrogen refueling station has a hydrogen storage device composed of a plurality of gas cylinders, and a distributor (filling machine) that fills the hydrogen supplied from the hydrogen storage device into the hydrogen tank of the vehicle. In addition, in a state where the connector provided at the front end of the distributor hose is connected to the filling port of the hydrogen tank, the hydrogen tank is filled with hydrogen gas using the pressure difference between the hydrogen storage device and the hydrogen tank.

In the process of transferring hydrogen through pressure difference or other transportation and use processes, hydrogen needs to be compressed to reduce the storage pressure and temperature of hydrogen. Existing compressors include crank connecting rod piston compressors and diaphragm compressors. These two compressors cannot be started directly. The high-pressure gas in the compressor must be released before the motor can drive the "empty" load to start the compressor. Therefore, the power consumption is large and the working noise is large; the diaphragm compressor depends on the diaphragm. Reciprocating flexure in the membrane cavity achieves gas compression, the life of the diaphragm is relatively short, and there is a risk of gas-liquid mixing when the diaphragm ruptures.

In addition, most of the existing hydrogen compressors can only achieve two-stage compression, and the compression efficiency needs to be improved; in order to achieve effective multi-stage compression of hydrogen, it is necessary to solve the connection and control problems between multi-stage compression and the problem of compressed hydrogen cooling. It is also necessary to design the hydrogen compression circuit reasonably to reduce vibration and noise, avoid the dangers caused by the mixing of oil and gas, and realize efficient multi-stage compression. Further improvements to the hydrogen compressor are required.

Summary of the invention

technical problem

The solution to the problem

Technical solutions

In order to realize the four-stage pressurization and compression of hydrogen, solve the problem of compression heat dissipation, improve compression efficiency, compressor stability, and reduce compressor vibration, the present invention provides an electro-hydraulic-driven piston hydrogen compressor and a compression method. The specific technical solutions are as follows.

An electric hydraulic driven piston type hydrogen compressor, including a hydraulic reversing system, a first two-stage compression cylinder, a second two-stage compression cylinder, a gas cooling system and a gas pipeline, a first two-stage compression cylinder and a second two-stage compression cylinder The compression cylinders are arranged in series through the gas pipeline. The hydraulic reversing system separately provides power to the first two-stage compression cylinder and the second two-stage compression cylinder. The gas cooling system is the first two-stage compression cylinder and the second two-stage compression cylinder. The two-stage compression cools separately.

Preferably, the first two-stage compression cylinder includes a first cylinder, a first cylinder piston, a second cylinder, a second cylinder piston, an oil cylinder, an oil cylinder piston, a piston rod and a supporting diaphragm, and is also connected with a first hydraulic system and a second cylinder. A cooling device and an oil-gas isolation and sealing structure; the diameter of the first cylinder is larger than the diameter of the second cylinder, and the first cylinder and the second cylinder are respectively coaxially connected with the oil cylinder through a supporting partition plate, and both ends of the piston rod A first cylinder piston and a second cylinder piston are respectively provided, and a cylinder piston is provided in the middle of the piston rod; the first hydraulic system controls the movement of the cylinder piston in the cylinder, and the piston rod drives the first cylinder piston and the second cylinder piston along the first A cylinder and a second cylinder move; the first cylinder piston and the second cylinder piston separate the space in the first cylinder and the second cylinder into two cavities; the air outlets of the two cavities of the first cylinder The air inlets of the two cavities of the second cylinder are respectively connected; the gas connecting pipeline connecting the first cylinder and the second cylinder cavity, and the air outlet connecting pipeline of the second cylinder cavity are provided with a first cooling device; An oil-gas isolation sealing structure and an oil-gas monitoring channel are arranged between the piston rod and the supporting partition.

Further preferably, the structure of the second two-stage compression cylinder is the same as that of the first two-stage compression cylinder, or the second two-stage compression cylinder includes a third cylinder, a third cylinder piston, a fourth cylinder, a fourth cylinder piston, an oil cylinder, The oil cylinder piston, the piston rod and the supporting diaphragm are also connected with the second hydraulic system, the second cooling device and the oil-gas isolation and sealing structure. The third cylinder and the fourth cylinder are respectively coaxially connected with the oil cylinder through the supporting diaphragm. The third cylinder and the fourth cylinder are symmetrical in structure. A third cylinder piston and a fourth cylinder piston are respectively provided at both ends of the piston rod, and a cylinder piston is provided in the middle of the piston rod; the second hydraulic system controls the cylinder piston in the cylinder Movement, the piston rod drives the third cylinder piston and the fourth cylinder piston to move along the third cylinder and the fourth cylinder respectively; the third cylinder piston and the fourth cylinder piston separate the space in the third cylinder and the fourth cylinder into Two cavities, a second cooling device is arranged on the gas connecting pipeline connected with the cavities; an oil-gas isolation and sealing structure is arranged between the piston rod and the supporting partition.

It is also preferred that the hydraulic reversing system includes a first hydraulic system and a second hydraulic reversing system. The first hydraulic system provides hydraulic oil for the first two-stage compression cylinder, and the second hydraulic system provides hydraulic oil for the second two-stage compression cylinder. ; The first hydraulic system and the second hydraulic system share an oil tank, and the oil tank is provided with an independent oil cooler and an oil pump to form an oil tank cooling circuit.

Preferably, the first hydraulic system and the second hydraulic system both include an oil pump, an accumulator, an integrated control module, an oil cylinder, a control cover plate and a reversing valve, and the integrated control module includes a pressure gauge, two two-way cartridge valves, Hydraulic reversing valve and electromagnetic reversing valve; the oil pump is connected to the oil tank through the pipeline, the oil pump pumps the hydraulic oil to the integrated control module, and the integrated control module is connected to the cylinder through the pipeline; an accumulator is also provided between the oil pump and the integrated control module , The control cover is plugged into the two-way cartridge valve of the integrated control module, and one of the control covers is also connected with an independent solenoid control valve.

Further preferably, the accumulator includes an upper end cover, a lower end cover, a cylinder barrel, and a piston. Both ends of the cylinder barrel are respectively provided with an upper end cover and a lower end cover, and the piston is provided in the cylinder barrel; the upper end cover is provided with gas Channel, the lower end cover is provided with a hydraulic oil channel; the piston is also provided with a boss, and the lower end cover is provided with a groove matching the boss; the bottom surface of the groove is provided with an oil outlet leading to the lower end A damper is arranged in the oil outlet hole on the outer surface of the cover.

It is also preferred that the gas pipeline includes an inlet pipe and an outlet pipe, the branch of the inlet pipe is also provided with a nitrogen replacement inlet, the trunk of the inlet pipe is connected to the first two-stage compression cylinders, and the trunk of the inlet pipe is provided with A pressure gauge and a filter, the filter is also connected with a drain valve; the air inlet pipe and the air outlet pipeline are provided with pneumatic valves, and the pneumatic valves are respectively connected to the instrument air inlet; the air outlet pipe is divided into The high-pressure gas outlet branch pipe and the medium-pressure gas outlet branch pipe, the high-pressure gas outlet branch pipe and the medium-pressure gas outlet branch pipe are sequentially provided with pneumatic valves, pressure gauges and nitrogen replacement exhaust gas detection ports from upstream to downstream of the gas. A one-way valve is provided.

Further, the gas pipeline between the first two-stage compression cylinder and the second two-stage compression cylinder, and the gas pipeline between the second two-stage compression cylinder and the gas outlet pipe are provided with a safety relief pipeline.

An electro-hydraulic-driven piston-type hydrogen compression method uses the above-mentioned electro-hydraulic-driven piston-type hydrogen compressor to perform four-stage compression and boosting, and the steps include:

Step 1: The gas enters the first cylinder of the first two-stage compression cylinder from the intake pipe. The first-stage compression is completed on both sides of the first-cylinder piston, and the first-stage compressed gas enters the first cooler;

Step 2: The cooled first-stage compressed gas enters the second cylinder of the first two-stage compression cylinder, and the second-stage compression is performed on both sides of the second cylinder piston, and the second-stage compressed gas enters the first cooler;

Step 3: The cooled two-stage compressed gas enters the third and fourth cylinders of the second two-stage compression cylinder respectively. The third and fourth cylinders respectively complete three-stage compression on one side of the cylinder piston. The gas enters the second cooler;

Step 4: The cooled three-stage compressed gas crosses into the third and fourth cylinders of the second two-stage compression cylinder. The third and fourth cylinders complete the three-stage compression to complete the four-stage compression in the opposite cavity. After stage compression, the gas enters the second cooler; then it is discharged through the outlet pipe.

Preferably, the hydraulic reversing system controls the stroke and frequency of the cylinder piston; the diameter ratio of the first cylinder and the second cylinder of the first cylinder piston adjusts the compression ratio of the first two-stage compression cylinder, and the piston of the second two-stage compression cylinder The rod diameter adjusts the compression ratio of the second two-stage compression cylinder.

The beneficial effects of the invention

Beneficial effect

The beneficial effects of the present invention include:

(1) An electric hydraulic driven piston hydrogen compressor is provided. The compressor realizes the four-stage compression of hydrogen through the series connection of the first two-stage compression cylinder and the second two-stage compression cylinder. The compressor uses a hydraulic reversing system. The electric motor drives the oil pump and completes the reciprocating movement. The cooling system cools the hydrogen compressed in each stage, thereby ensuring that the temperature of the hydrogen does not rise during the compression process. The gas pipeline is connected to the first and second stages of the compression cylinders. The stage compression cylinder and gas cooling ensure the continuity and stability of the four stage compression.

(2) The first two-stage compression cylinder of the compressor uses an asymmetric two-stage double-acting piston compression cylinder. The first-stage compression and the second-stage compression of the compression cylinder increase the compression efficiency of the gas simultaneously, and the exhaust temperature is stable. The pipeline pulsation is small; the second two-stage compression cylinder of the compressor uses a symmetrical two-stage double-acting piston compression cylinder. The two-stage double-acting compression is realized through the symmetrical two cylinders, which simplifies the installation structure of the gas compression cylinder and improves The sealing performance of the compression cylinder and the stability of the system.

(3) The hydraulic reversing system of the compressor solves the problem of overpressure and pulsation in the work of the hydraulic system. The accumulator reduces the impact of the hydraulic system and reduces the range of oil pressure changes. It can also reduce the vibration and noise of the equipment. Protect the moving parts; the integrated control module improves the integration of the hydraulic system, and can better control the hydraulic reversal to achieve overpressure overflow; the first hydraulic system and the second hydraulic system share the oil tank, and the cooler and the cylinder hydraulic circuit are parallel It is arranged so that the hydraulic oil can be cooled better independently and avoid the temperature rise of the device.

(4) The method of using the compressor to achieve hydrogen compression realizes the four-stage compression and boosting of hydrogen. Combined with the device, the compressed gas is cooled after each stage of compression, so as to ensure the temperature of the compressed gas, and through hydraulic pressure The reversing system accurately controls the stroke of the compression cylinder, so as to achieve accurate control of the compression process.

In addition, the electro-hydraulic-driven piston hydrogen compressor and the method of using the compressor to achieve four-stage compression and boosting have the advantages of flexible control, high compression efficiency, and convenient maintenance.

Brief description of the drawings

Description of the drawings

Figure 1 is a schematic diagram of the principle structure of an electro-hydraulic piston hydrogen compressor;

Figure 2 is a schematic diagram of the overall structure of an electro-hydraulic piston hydrogen compressor;

Figure 3 is a side view of an electro-hydraulic piston hydrogen compressor;

Figure 4 is another side view of the electro-hydraulic piston hydrogen compressor;

Figure 5 is a plan view of an electro-hydraulic piston hydrogen compressor;

Figure 6 is a schematic diagram of the structure and working principle of the first two-stage compression cylinder;

Figure 7 is a schematic diagram of the structure and working principle of the second two-stage compression cylinder;

Figure 8 is a schematic diagram of the principle of the hydraulic reversing system;

Figure 9 is a schematic diagram of the structure of the accumulator;

Figure 10 is a schematic diagram of the gas pipeline;

Figure 11 is a schematic diagram of the oil-gas isolation and sealing structure;

Figure 12 is a schematic diagram of the first two-stage compression cylinder;

Figure 13 is a schematic diagram of the second two-stage compression cylinder;

In the picture: 1- hydraulic reversing system; 11- first hydraulic system; 12- second hydraulic system; 13- oil pump; 14- accumulator; 141- upper end cover; 142- lower end cover; 143- cylinder; 144 -Piston; 15-Integrated control module; 16-Oil tank; 17-Control cover plate; 18-Reversing valve; 19-Oil cooler; 2-First two-stage compression cylinder; 21-First cylinder, 22- First cylinder piston; 23-second cylinder; 24-second cylinder piston; 25-cylinder; 26-cylinder piston; 27-piston rod; 28-support partition; 3-second two-stage compression cylinder; 31-th Three cylinders; 32-third cylinder piston; 33-fourth cylinder; 34-fourth cylinder piston; 4-gas cooling system; 41-first cooling device; 42-second cooling device; 5-gas pipeline; 501 -Inlet pipe; 502- Outlet pipe; 503- Nitrogen replacement inlet; 504- Pressure gauge; 505- Check valve; 506- Safety valve; 507- Pneumatic valve; 508- High pressure gas outlet branch pipe; 509- Medium pressure gas outlet Branch pipe; 510-nitrogen replacement exhaust detection port; 511-filter; 512-temperature meter; 513-ball valve; 6-oil and gas isolation sealing structure; 61-gas sealing part; 62-oil sealing part; 63-oil and gas isolation sealing part ; 64-Air tightness detection channel; 65-Oil tightness detection channel.

Invention embodiment

Embodiments of the invention

With reference to FIGS. 1 to 13, the specific implementation of an electro-hydraulic driven piston hydrogen compressor and compression method provided by the present invention is as follows.

An electric hydraulic driven piston hydrogen compressor specifically includes a hydraulic reversing system 1, a first two-stage compression cylinder 2, a second two-stage compression cylinder 3, a gas cooling system 4, and a gas pipeline 5. The first two-stage compression cylinder 2 and the second two-stage compression cylinder 3 are arranged in series through the gas pipeline, the hydraulic reversing system separately provides power to the first two-stage compression cylinder 2 and the second two-stage compression cylinder 3, and the gas cooling system 4 is the first two The two-stage compression of the two-stage compression cylinder 2 and the second two-stage compression cylinder 3 cool down respectively. The structure and principle of the compressor are shown in Figure 1. The compressor realizes the four-stage compression of hydrogen through the series connection of the first two-stage compression cylinder and the second two-stage compression cylinder. The compressor is driven by the motor of the hydraulic commutation system. The oil pump completes reversing and reciprocating movement. The cooling system cools the hydrogen compressed in each stage, thereby ensuring that the temperature of the hydrogen does not rise during the compression process. The gas pipeline is connected to the first two-stage compression cylinder and the second two-stage compression cylinder And gas cooling ensures the continuity and stability of the four-stage compression.

The specific structure of the first two-stage compression cylinder 2 includes a first cylinder 21, a first cylinder piston 22, a second cylinder 23, a second cylinder piston 24, an oil cylinder 25, an oil cylinder piston 26, a piston rod 27 and a supporting partition 28, and The first hydraulic system 11, the first cooling device 41 and the oil-gas isolation and sealing structure 6. The diameter of the first cylinder 21 is greater than the diameter of the second cylinder 23, and the gas enters the small-diameter cylinder after one-stage compression in the large-diameter cylinder, which can further compress the gas, thereby realizing more efficient compressed gas. The first cylinder 21 and the second cylinder 23 are respectively coaxially connected by a supporting partition 28 and an oil cylinder 25. An oil-gas isolation and sealing structure is provided between the support partition and the piston rod. The first cylinder piston and the piston rod are respectively provided at both ends of the piston rod. For the second cylinder piston, an oil cylinder piston is arranged in the middle of the piston rod 27. The first hydraulic system 11 controls the movement of the cylinder piston in the cylinder, and the piston rod 27 drives the first cylinder piston and the second cylinder piston to move along the first cylinder and the second cylinder respectively. The first cylinder piston 22 and the second cylinder piston 24 separate the space in the first cylinder and the second cylinder into two cavities, respectively. The outlets of the two cavities of the first cylinder are connected to the two cavities of the second cylinder. The air inlet, the gas connecting pipeline connecting the first cylinder and the second cylinder cavity, and the air outlet connecting pipeline of the second cylinder cavity are all equipped with a first cooling device, and oil and gas are arranged between the piston rod and the supporting partition. Isolate the sealing structure and the oil and gas monitoring channel to realize the oil and gas isolation and monitor the effectiveness of the oil and gas isolation.

The first two-stage compression cylinder 2 achieves two-stage compression. The steps of gas compression include: first-stage compression. The gas enters both sides of the piston in the first cylinder of the first two-stage compression cylinder from the intake pipe. Driven by the piston of the oil cylinder, it reciprocates. The gas completes one stage of compression on both sides of the piston of the first cylinder. The compressed gas enters the first cooler for cooling; the second stage is compressed, and the cooled first stage compressed gas enters In the second cylinder of the first two-stage compression cylinder, two-stage compression is completed on both sides of the second cylinder piston, and the gas after the two-stage compression enters the first cooler again. The first cylinder and the second cylinder may also be provided with a displacement sensor, which transmits a position signal to the first hydraulic system, and the first hydraulic system adjusts the movement of the piston of the oil cylinder according to the signal.

The specific structure of the second two-stage compression cylinder 3 may be the same as or different from that of the first two-stage compression cylinder. If different, the structure of the second two-stage compression cylinder includes a third cylinder 31, a third cylinder piston 32, and a fourth cylinder 33. , The fourth cylinder piston 34, the oil cylinder 25, the oil cylinder piston 26, the piston rod 27 and the supporting partition 28, as well as the second hydraulic system 12, the second cooling device 42, and the oil and gas isolation sealing structure 6. The third cylinder and the fourth cylinder are respectively coaxially connected with the oil cylinder 25 through the supporting partition 28, the third cylinder 31 and the fourth cylinder 33 are symmetrical in structure, and both ends of the piston rod are respectively provided with a third cylinder piston and a fourth cylinder piston, An oil cylinder piston is arranged in the middle of the piston rod. The second hydraulic system 12 controls the movement of the cylinder piston in the cylinder, and the piston rod 27 drives the third cylinder piston and the fourth cylinder piston to move along the third cylinder and the fourth cylinder respectively. The third cylinder piston 32 and the fourth cylinder piston 34 separate the space in the third cylinder and the fourth cylinder into two cavities. The gas connecting pipeline connected to the cavities is provided with a second cooling device 42, a piston rod and a support. An oil-gas isolation and sealing structure 6 is arranged between the partitions.

The second two-stage compression cylinder 3 realizes two-stage compression. The steps of gas compression include: the cooled two-stage compressed gas enters the third and fourth cylinders of the second two-stage compression cylinder respectively, and the third and fourth cylinders Three-stage compression is completed on one side of the cylinder piston, and the gas after the three-stage compression enters the second cooler; the cooled three-stage compressed gas crosses into the third and fourth cylinders of the second two-stage compression cylinders, and the third The cylinder and the fourth cylinder complete the three-stage compression and the cavity on the opposite side completes the four-stage compression. After the four-stage compression, the gas enters the second cooler; then it is discharged through the air outlet pipe. The third cylinder and the fourth cylinder may also be provided with a displacement sensor, which transmits a position signal to the first hydraulic system, and the first hydraulic system adjusts the movement of the piston of the oil cylinder according to the signal.

The oil and gas isolation and sealing structure 6 of the first two-stage compression cylinder 2 and the second two-stage compression cylinder 3, the specific oil and gas isolation and sealing structure 6 includes an air sealing component 61, an oil sealing component 62, an oil and gas isolation sealing component 63, and an air tightness detection channel 64 and the oil tightness detection channel 65. Between the piston rod 27 and the support partition 28, an air sealing member 61 is provided near the cylinder side, and an oil sealing member 62 is provided near the oil cylinder side. One of the air sealing member 61 and the oil sealing member 62 An oil-gas isolation sealing member 63 is provided between. An oil tightness detection channel 64 is also provided on the support partition between the oil sealing component 62 and the oil and gas isolation sealing component 63, and the support partition between the gas sealing component 61 and the oil and gas isolation and sealing component 63 is also provided with air tightness. Detection channel 64. The oil-air isolation and sealing structure 6 uses air-sealing parts, oil-sealing parts, and oil-air isolation and sealing parts to isolate cylinders and oil cylinders respectively. The cylinders include the first cylinder, the second cylinder, the third cylinder, and the fourth cylinder to avoid the mixing of oil and gas. The air tightness detection channel and the oil tightness detection channel realize real-time monitoring of the effectiveness of the oil and gas seal structure, avoiding the danger of sealing failure after the oil and gas are mixed, and the leaked medium can also be recovered through the detection channel.

The first two-stage compression cylinder 2 of the compressor uses an asymmetric two-stage double-acting piston compression cylinder. The first-stage compression and the second-stage compression of the compression cylinder improve the compression efficiency of the gas, and the exhaust temperature is stable. The pulsation is small; the second two-stage compression cylinder of the compressor adopts a symmetrical two-stage double-acting piston compression cylinder, which realizes two-stage double-acting compression through the symmetrical two cylinders, which simplifies the installation structure of the gas compression cylinder and improves the compression cylinder The sealing performance and system stability.

The hydraulic reversing system 1 specifically includes a first hydraulic system 11 and a second hydraulic reversing system 12, which have the same structure. The first hydraulic system provides hydraulic oil for the first two-stage compression cylinder, and the second hydraulic system is the second two-stage compression The cylinder provides hydraulic oil. The first hydraulic system and the second hydraulic system share an oil tank, and the oil tank is provided with an independent oil cooler and an oil pump to form an oil tank cooling circuit. Both the first hydraulic system and the second hydraulic system include an oil pump 13, an accumulator 14, an integrated control module 15, a mailbox 16, an oil cylinder 25, a control cover plate 17 and a reversing valve 18. The integrated control module 15 includes a pressure gauge, two Two-way cartridge valve, hydraulic directional valve and electromagnetic directional valve. The oil pump 13 is connected to the oil tank through a pipeline, the oil pump 13 pumps hydraulic oil to the integrated control module, and the integrated control module 15 is connected to the oil cylinder through the pipeline. An accumulator is also arranged between the oil pump and the integrated control module, the control cover plate 17 is plugged into the two-way cartridge valve of the integrated control module, and one of the control cover plates is also connected with an independent electromagnetic control valve.

When the first hydraulic system 11 or the second hydraulic system 12 is working, the hydraulic oil is sucked from the oil tank through the filter to the oil pump. After being pressurized by the oil pump, the hydraulic oil is connected to the inlet G of the integrated control module through the pipeline. When the electromagnetic directional valve connected to the control cover is in the non-operating position, the spool of the two-way cartridge valve is not compressed, and the spool opens under the action of oil pressure, and the hydraulic oil returns through the outlet 0 of the integrated control module. Enter the oil return filter and return to the oil tank. When the electromagnetic reversing valve connected to the control cover is in the working position, because the two-way cartridge valve is closed under the action of the spring, the hydraulic oil enters the hydraulic reversing valve through the two-way cartridge valve on the other side. Lead the control oil circuit from the internal outlet of the hydraulic directional valve to the electromagnetic directional valve. When the electromagnetic reversing valve is in the working position and the non-working position, the control oil enters the left or right side of the spool of the hydraulic reversing valve to control the spool to move left and right. When the spool of the hydraulic reversing valve is at the left position as shown in the figure, the main oil circuit hydraulic oil enters from port P of the hydraulic reversing valve to port A, the hydraulic oil enters the left side of the cylinder, and the cylinder piston moves to the right. The hydraulic oil on the right side of the cylinder piston returns oil through the B port of the hydraulic directional valve, enters the two-way cartridge valve, and returns oil from the outlet 0 of the hydraulic manifold. When the hydraulic reversing valve core is in the right position, the main oil circuit hydraulic oil enters from port P of the hydraulic reversing valve to port B, the hydraulic oil enters the right side of the cylinder, and the cylinder piston moves to the left. At the same time, the hydraulic oil on the left side of the cylinder piston returns oil through the A port of the hydraulic directional valve, and returns oil through the two-way cartridge valve. When the oil temperature rises, the oil pump is started, and the hydraulic oil is drawn from the oil tank and injected into the oil cooler. After the hydraulic oil is cooled, it returns to the oil tank.

The accumulator in the hydraulic reversing system includes an upper end cover 141, a lower end cover 142, a cylinder 143, and a piston 144. The upper end cover 141 and the lower end cover 142 are detachable installation structures, and the piston 144 is arranged in the cylinder. The piston 144 is installed in cooperation with the cylinder 143. The cylinder 143 is generally cylindrical. Both ends of the cylinder 143 are respectively provided with an upper end cover and a lower end cover. The upper end cover 141 is provided with a gas channel for injecting pressurized gas, including air, nitrogen, etc., and the lower end cover 142 is provided with a hydraulic oil channel for connecting the hydraulic oil channel. The piston 144 is also provided with a boss, and the lower end cover 142 is provided with a groove that matches with the boss. The piston buffer is realized by the boss on the piston 144 and the groove on the lower end cover, avoiding a sudden drop in the pressure of the hydraulic chamber. The piston directly impacts the lower end cover. The bottom surface of the groove is provided with an oil outlet leading to the outer surface of the lower end cover, which discharges the hydraulic oil in the groove, and a damper is installed in the oil outlet, thereby generating a reaction force against the remaining hydraulic oil in the groove of the lower end cover It is limited to better realize the function of the accumulator.

The hydraulic reversing system of the compressor solves the problem of overpressure and pulsation in the work of the hydraulic system. The accumulator reduces the impact of the hydraulic system and reduces the range of oil pressure changes. It can also reduce the vibration and noise of the equipment and protect the moving parts. ; The integrated control module improves the integration of the hydraulic system, and can better control the hydraulic reversal to achieve overpressure overflow; the first hydraulic system and the second hydraulic system share the oil tank, and the cooler and the cylinder hydraulic circuit are arranged in parallel, thus The hydraulic oil can be cooled better independently to avoid the temperature rise of the device.

The gas pipeline 5 includes an inlet pipe 501 and an outlet pipe 502. The branch of the inlet pipe 501 is also provided with a nitrogen replacement inlet 503 to facilitate system maintenance. After system maintenance, the system is filled with nitrogen through the nitrogen replacement inlet 503 Ensure that the compressor will not run idly, while avoiding hydrogen pollution. The dry path of the intake pipe 501 is connected to the first two-stage compression cylinder 2, and the dry path of the intake pipe 501 is provided with a pressure gauge 504 and a filter 511. The filter 511 is also connected with a drain valve to ensure the cleanliness of the gas. Pneumatic valves 507 are provided on the trunk road of the air intake pipe 501 and the air outlet pipe 502, and the pneumatic valves 507 are respectively connected to the instrument air inlet. The air outlet pipe 502 is divided into a high-pressure gas outlet branch pipe and a medium-pressure gas outlet branch pipe. The high-pressure gas outlet pipe and the medium-pressure gas outlet branch pipe are equipped with a pneumatic valve 507, a pressure gauge 504 and a nitrogen displacement exhaust gas detection in sequence from upstream to downstream. Port 510, the high-pressure gas outlet branch pipe 508 is also provided with a one-way valve 505 to prevent backflow of gas; the nitrogen replacement exhaust gas detection port 510 is used to discharge nitrogen gas and sample and monitor hydrogen. On the gas pipeline between the first two-stage compression cylinder 2 and the second two-stage compression cylinder 3, and on the gas pipeline between the second two-stage compression cylinder and the gas outlet pipe, a safety relief pipeline is provided to ensure the pipeline Safe operation.

Step 1: The gas enters the first cylinder of the first two-stage compression cylinder from the intake pipe, and the first-stage compression is completed on both sides of the piston of the first cylinder, and the gas after the first-stage compression enters the first cooler;

In an electro-hydraulic-driven piston hydrogen compression method, a hydraulic reversing system controls the stroke and frequency of the cylinder piston. The displacement sensor is set in the first cylinder as an example. Set the reciprocating stroke of the piston of the first cylinder to L, where the upper limit value is 0 and the lower limit value is L; set the target upper limit value A0 and target lower limit value of the cylinder piston movement B0. First, set the upper reversing point A1 and the initial reversing point B1 through the controller, where A1=0+L1, B1=L-L2, and the values of L1 and L2 can ensure that the piston does not collide with the cylinder during reciprocating motion. Then start the hydraulic system and get the actual upper limit value A2 and lower limit value B2 during the up and down reciprocating process of the piston after the operation is stable; set the reversing point increments P1 and P2, which are generally small. The hydraulic system continues to run, adding increments, the reversing point of the next cycle becomes the upper reversing point A1+P1, and the lower reversing point becomes B1-P2. After one cycle, the new upper limit of the actual reversing point is read Value A3 and lower limit value B3; compare A3 with A0, and B3 with B0. When A3>A0, B3<B0, continue to perform the commutation point increments P1 and P2; until A3=A0, B3=B0, the dynamic commutation adjustment is completed. If the working conditions change during operation and A3<A0 or B3>B0 appears, it means that the stroke exceeds the limit, the system automatically resets, and the above dynamic adjustment process is repeated. The system can control the up and down stroke of the hydraulic reversing system by adjusting the target upper and lower limit values. When the reciprocating speed of the piston and piston rod changes, the system can automatically keep the actual stroke equal to the target value.

The diameter ratio of the first cylinder and the second cylinder of the first two-stage compression cylinder adjusts the compression ratio of the first two-stage compression cylinder, and the piston rod diameter of the second two-stage compression cylinder adjusts the compression ratio of the second two-stage compression cylinder. The diameter setting between the first cylinder and the second cylinder is the key to realize the production of compression cylinders with different compression ratios. This is illustrated by the following examples: Example 1. The length of the first cylinder is 350mm, the inner diameter is 160mm, and the second The length of the cylinder is 350mm and the inner diameter is 110mm, then the compression ratio of the first two stages of the compression cylinder is 2.1:1; Example 2. The length of the first cylinder is 350mm, the inner diameter is 250mm, and the length of the second cylinder is 350mm. If the inner diameter is 110mm, the compression ratio of the first two stages of the compression cylinder is 5.1:1; Example 3. The length of the first cylinder is 350mm, the inner diameter is 160mm, the length of the second cylinder is 350mm, and the inner diameter is 80mm, then this The compression ratio of the first two stages of the compression cylinder is 4:1.

The method of using this compressor to achieve hydrogen compression realizes four-stage compression and boosting of hydrogen. Combined with this device, the compressed gas is cooled after compression in each stage, so as to ensure the temperature of the compressed gas, and the hydraulic reversing system Accurately control the stroke of the compression cylinder, so as to achieve accurate control of the compression process. In addition, the electro-hydraulic-driven piston hydrogen compressor and the method of using the compressor to achieve four-stage compression and boosting have the advantages of flexible control, high compression efficiency, and convenient maintenance.

The parts not mentioned in the present invention can be realized by adopting or learning from existing technologies.

In addition, many uses such as "first two-stage compression cylinder, second two-stage compression cylinder, gas cooling system, gas pipeline, first cylinder, second cylinder, oil cylinder, oil cylinder piston, support diaphragm, "Hydraulic reversing system, oil and gas isolation and sealing structure" and other terms, but the possibility of using other terms is not excluded. These terms are used only for more convenient description and explanation of the essence of the present invention; interpretation of them as any kind of additional limitation is contrary to the spirit of the present invention.

Of course, the above description is not a limitation of the present invention, and the present invention is not limited to the above examples. Changes, modifications, additions or substitutions made by those skilled in the art within the essential scope of the present invention shall also belong to the present invention. The scope of protection of the invention.

Claims

An electric hydraulic driven piston type hydrogen compressor, characterized in that it comprises a hydraulic reversing system, a first two-stage compression cylinder, a second two-stage compression cylinder, a gas cooling system and a gas pipeline. The first two-stage compression The cylinder and the second two-stage compression cylinder are arranged in series through a gas pipeline. The hydraulic reversing system separately provides power to the first two-stage compression cylinder and the second two-stage compression cylinder. The gas cooling system is the first two-stage compression cylinder. The two-stage compression of the two-stage compression cylinder and the second two-stage compression cylinder are respectively cooled.
The electro-hydraulic-driven piston hydrogen compressor according to claim 1, wherein the first two-stage compression cylinder includes a first cylinder, a first cylinder piston, a second cylinder, a second cylinder piston, and an oil cylinder , The oil cylinder piston, the piston rod and the supporting partition, and also connected with the first hydraulic system, the first cooling device and the oil-gas isolation and sealing structure; the diameter of the first cylinder is larger than the diameter of the second cylinder, the first cylinder and the second cylinder The two cylinders are respectively coaxially connected with the oil cylinder through a supporting partition plate, a first cylinder piston and a second cylinder piston are respectively arranged at both ends of the piston rod, and an oil cylinder piston is arranged in the middle of the piston rod; the first hydraulic system controls the inside of the oil cylinder The piston of the oil cylinder moves, the piston rod drives the first cylinder piston and the second cylinder piston to move along the first cylinder and the second cylinder respectively; the first cylinder piston and the second cylinder piston separate the space in the first cylinder and the second cylinder respectively Are two cavities; the air outlets of the two cavities of the first cylinder are respectively connected to the air inlets of the two cavities of the second cylinder; the first cylinder and the second cylinder cavity are connected to the gas connecting pipeline, the second A first cooling device is arranged on the air outlet connecting pipeline of the cylinder cavity; an oil-gas isolation sealing structure and an oil-gas monitoring channel are arranged between the piston rod and the supporting partition.
The electric hydraulic drive piston hydrogen compressor according to claim 2, wherein the structure of the second two-stage compression cylinder is the same as the structure of the first two-stage compression cylinder, or the second two-stage compression cylinder includes The third cylinder, the third cylinder piston, the fourth cylinder, the fourth cylinder piston, the oil cylinder, the oil cylinder piston, the piston rod and the supporting partition are also connected with the second hydraulic system, the second cooling device and the oil-gas isolation and sealing structure. The third cylinder and the fourth cylinder are respectively coaxially connected with the oil cylinder through a supporting partition plate. The third cylinder and the fourth cylinder are symmetrical in structure. A third cylinder piston and a fourth cylinder piston are respectively provided at both ends of the piston rod. An oil cylinder piston is arranged in the middle of the piston rod; the second hydraulic system controls the movement of the oil cylinder piston in the oil cylinder, and the piston rod drives the third cylinder piston and the fourth cylinder piston to move along the third cylinder and the fourth cylinder respectively; the third cylinder The piston and the fourth cylinder separate the space in the third cylinder and the fourth cylinder into two cavities. The gas connecting pipeline connected to the cavities is provided with a second cooling device; between the piston rod and the support partition Equipped with oil-gas isolation and sealing structure.
The electro-hydraulic-driven piston hydrogen compressor according to claim 1, wherein the hydraulic reversing system includes a first hydraulic system and a second hydraulic reversing system, and the first hydraulic system is a first hydraulic system. The two-stage compression cylinder provides hydraulic oil, and the second hydraulic system provides hydraulic oil for the second two-stage compression cylinder; the first hydraulic system and the second hydraulic system share an oil tank, and the oil tank is provided with an independent oil cooler and an oil pump to form oil tank cooling Loop.
The electro-hydraulic-driven piston hydrogen compressor according to claim 4, wherein the first hydraulic system and the second hydraulic system both include an oil pump, an accumulator, an integrated control module, an oil cylinder, and a control cover. And a reversing valve, the integrated control module includes a pressure gauge, two two-way cartridge valves, a hydraulic reversing valve and an electromagnetic reversing valve; the oil pump is connected to the oil tank through a pipeline, and the oil pump sends the hydraulic oil to the integrated control Module, the integrated control module is connected to the oil cylinder through a pipeline; an accumulator is also provided between the oil pump and the integrated control module, and the control cover is plugged into the two-way cartridge valve of the integrated control module, one of which controls The cover plate is also connected with an independent solenoid control valve.
The electric hydraulic driven piston hydrogen compressor according to claim 5, wherein the accumulator includes an upper end cover, a lower end cover, a cylinder, and a piston, and both ends of the cylinder are respectively provided with upper ends Cover and lower end cover, the piston is arranged in the cylinder; the upper end cover is provided with a gas channel, the lower end cover is provided with a hydraulic oil channel; the piston is also provided with a boss, the lower end cover is provided with a Matching groove; the bottom surface of the groove is provided with an oil outlet leading to the outer surface of the lower end cover, and a damper is provided in the oil outlet.
The electro-hydraulic-driven piston hydrogen compressor according to claim 1, wherein the gas pipeline includes an inlet pipe and an outlet pipe, and a nitrogen replacement inlet is provided on the branch of the inlet pipe, The dry path of the intake pipe is connected to the first two-stage compression cylinders, and the dry path of the intake pipe is provided with a pressure gauge and a filter, and the filter is also connected with a sewage valve; the dry path and the outlet pipe of the intake pipe are provided with pneumatic The pneumatic valve and the pneumatic valve are respectively connected to the instrument air inlet; the trunk of the air outlet is divided into a high-pressure gas outlet branch and a medium-pressure gas outlet branch. The high-pressure gas outlet branch and the intermediate pressure gas outlet branch are provided with pneumatic Valves, pressure gauges and nitrogen replacement exhaust gas detection ports, and the high-pressure gas outlet branch pipes are also provided with a one-way valve.
The electric-hydraulic-driven piston hydrogen compressor according to claim 7, wherein the gas pipeline between the first two-stage compression cylinder and the second two-stage compression cylinder, and the second two-stage compression The gas pipeline between the cylinder and the air outlet pipe is provided with a safety relief pipeline.
An electro-hydraulic-driven piston-type hydrogen compression method using an electro-hydraulic-driven piston-type hydrogen compressor according to any one of claims 1 to 8 to perform four-stage compression and boosting, and the steps include:

Step 1: The gas enters the first cylinder of the first two-stage compression cylinder from the intake pipe, and the first-stage compression is completed on both sides of the piston of the first cylinder, and the gas after the first-stage compression enters the first cooler;

Step 2: The cooled first-stage compressed gas enters the second cylinder of the first two-stage compression cylinder, and the second-stage compression is performed on both sides of the second cylinder piston, and the second-stage compressed gas enters the first cooler;

Step 3: The cooled two-stage compressed gas enters the third and fourth cylinders of the second two-stage compression cylinder. The third and fourth cylinders complete three-stage compression on one side of the cylinder piston. After the third-stage compression The gas enters the second cooler;

Step 4: The cooled three-stage compressed gas crosses into the third cylinder and the fourth cylinder of the second two-stage compression cylinder respectively. The third and fourth cylinders complete the three-stage compression to complete the four-stage compression in the opposite cavity. After stage compression, the gas enters the second cooler; then it is discharged through the outlet pipe.
An electro-hydraulic-driven piston hydrogen compression method according to claim 9, wherein the hydraulic reversing system controls the stroke and frequency of the cylinder piston; the first cylinder and the second cylinder of the first two-stage compression cylinder The diameter ratio adjusts the compression ratio of the first two-stage compression cylinder, and the piston rod diameter of the second two-stage compression cylinder adjusts the compression ratio of the second two-stage compression cylinder.