CN116163916A - Oil pressure limiting system of hydrogen diaphragm compressor and control method thereof - Google Patents

Abstract

The invention belongs to the technical field of diaphragm compressors, and specifically discloses an oil pressure limiting system of a hydrogen diaphragm compressor and a control method thereof. port and oil return port; diaphragm compressor includes membrane head oil chamber, middle body and crankcase connected in sequence; gear pump and overflow valve are arranged in the gear box, the inlet of the gear pump communicates with the oil pool of the crankcase, The outlet is connected to the oil return port of the oil injection pipeline; one end of the oil supply pipeline is connected to the oil supply port of the oil injection pipeline, and the other end is connected to the oil cavity of the membrane head; one end of the lubricating oil line is connected to the filter , the other end is connected with the crankshaft; one end of the oil pressure limiting pipeline is connected with the membrane head oil cavity, and the other end is connected with the oil pool of the crankcase. In the present invention, by increasing the number of compression stages of the diaphragm compressor and correspondingly increasing the oil pressure limiting system of the compressor, the hydrogen gas used in the long hydrogen tube trailer can be used at about 1 MPa, the utilization rate of hydrogen gas is improved, and the cost is reduced.

Description

An oil pressure limiting system of a hydrogen diaphragm compressor and its control method

technical field

The invention relates to the technical field of hydrogen diaphragm compressors, in particular to an oil pressure limiting system of a hydrogen diaphragm compressor and a control method thereof.

Background technique

Hydrogen refueling station is an emerging industry. At present, the main transportation mode of hydrogen in hydrogen refueling stations on the market is long-tube trailer transportation (gaseous), but hydrogen is the gas with the smallest molecular weight. Even if the long-tube trailer has a high pressure, the quality of hydrogen transported is relatively low. This leads to the fact that the transportation cost of hydrogen accounts for a large proportion of the cost of selling hydrogen.

In addition, limited by the characteristics of the diaphragm compressor, the hydrogen inlet pressure is maintained at 5-20MPa, and the long-tube trailer can only use hydrogen from 20MPa to about 6MPa, and there is still a large proportion of hydrogen that cannot be effectively utilized.

Contents of the invention

The purpose of the present invention is to overcome the technical problem in the background technology that the long-tube trailer has a large specific gravity and hydrogen cannot be effectively utilized, thereby providing an oil pressure limiting system of a hydrogen diaphragm compressor and a control method thereof.

In order to solve the above problems, the present invention provides an oil pressure limiting system of a hydrogen diaphragm compressor, the oil injection pipeline has an oil inlet, an oil discharge port, and one side of the oil injection pipeline is also provided with an oil replenishment port and an oil return mouth,

Diaphragm compressor, including membrane head oil chamber, middle body and crankcase connected in sequence, and a crankshaft is arranged in the crankcase;

The gear box is provided with a gear pump and an overflow valve, the inlet of the gear pump communicates with the oil pool of the crankcase, the outlet communicates with the oil return port of the oil injection pipeline, and the overflow One end of the flow valve communicates with the oil outlet of the gear pump, and the other end communicates with the oil pool of the crankcase;

An oil supply pipeline, one end of which is connected to the oil supply port of the oil injection pipeline, and the other end is connected to the oil cavity of the membrane head, and the oil supply pipeline is provided with a filter, a first check valve, and a plunger pump in sequence and the second check valve, after the hydraulic oil is pressurized by the plunger pump, oil is supplied to the membrane head oil cavity through the second check valve;

Lubricating oil passage, one end of the lubricating oil passage is connected with the filter, and the other end is connected with the crankshaft;

An oil pressure limiting pipeline, one end of which communicates with the membrane head oil cavity, and the other end communicates with the oil pool of the crankcase, and the oil pressure limiting pipeline is electrically connected with the diaphragm compressor to be suitable for For the different pressure ranges of the hydrogen storage tank, the high and low oil pressure limit pipelines are connected correspondingly.

Preferably, the oil pressure limiting pipeline includes a high oil pressure limiting pipeline and a low oil pressure limiting pipeline connected in parallel, and the high oil pressure limiting pipeline is suitable for hydrogen storage tank inlet pressure range of 5-20Mpa The low oil pressure restriction pipeline is suitable for opening at the inlet pressure range of the hydrogen storage tank in the range of 1-5Mpa.

Preferably, the high oil pressure limiting pipeline includes a high pressure solenoid valve, a high oil pressure limiter and a first pressure transmitter connected in sequence, the high pressure solenoid valve is electrically connected with the diaphragm compressor, and the high pressure The oil pressure setting range of the solenoid valve is 48-50Mpa.

Preferably, the low oil pressure limiting pipeline includes a low pressure solenoid valve, a low oil pressure limiter and a second pressure transmitter connected in sequence, the low pressure solenoid valve is electrically connected to the diaphragm compressor, and the low pressure The oil pressure setting range of the solenoid valve is 5-7Mpa.

Preferably, a safety valve is connected between the outlet of the gear pump and the crankcase, and the pressure preset value of the safety valve is not greater than 5.5MPa, so as to be suitable for adjusting the pressure of the gear pump.

Preferably, a heater is also provided in the oil pool of the crankcase, which is suitable for heating the hydraulic oil when the diaphragm compressor is stopped, so that the hydraulic oil of the diaphragm compressor can maintain a certain temperature.

Preferably, a third check valve is further provided in the oil supply line close to the oil cavity of the membrane head.

Preferably, the gear pump is driven by a separate motor.

Compared with the prior art, the oil pressure limiting system of the hydrogen diaphragm compressor according to the present invention has the following beneficial effects:

1. By increasing the number of compression stages of the compressor and correspondingly increasing the oil pressure limiting system of the compressor, the hydrogen gas used in the hydrogen long tube trailer can be used at about 1MPa, which greatly improves the utilization rate and reduces the cost;

2. Use one compressor to meet the effect of two compressors, and increase the hydrogen utilization rate of TT vehicles.

The present invention also provides an operation control method of the oil pressure limiting system of the hydrogen diaphragm compressor, the control method specifically includes:

S1: According to the pressure range of the hydrogen storage tank of the TT vehicle, judge whether it is necessary to replenish oil,

S2: If oil replenishment is required, interlock the hydrogen diaphragm compressor according to the pressure range of the hydrogen storage tank, and open the high oil pressure limiting pipeline or the low oil pressure limiting pipeline;

S3: Open the oil supply pipeline, start the gearbox, and the hydrogen diaphragm compressor starts to replenish oil, overflow oil, and realize the compression of hydrogen in the hydrogen storage tank; if no oil replenishment is required, start the hydrogen diaphragm compressor directly;

S4: After oil replenishment is completed, disconnect the first check valve and the second check valve, open the overflow valve and safety valve, and enter the pre-operation stage of the hydrogen diaphragm compressor;

S5: After the pre-operation is completed and the motor reaches normal speed, close the high-pressure solenoid valve and low-pressure solenoid valve, disconnect the oil supply line, and the compressor enters the working state.

Preferably, in step S2, the controlled interlocks the hydrogen diaphragm compressor according to the pressure range of the hydrogen storage tank, and opens the high oil pressure limiting pipeline or the low oil pressure limiting pipeline, specifically including:

S21: When the inlet pressure range of the hydrogen storage tank is 5-20Mpa, the high oil pressure limiting pipeline is opened, the low oil pressure limiting pipeline is closed, and the high pressure oil pipeline is unobstructed to compress the hydrogen to 45MPa bottle group for storage;

S22: When the inlet pressure range of the hydrogen storage tank is 1-5Mpa, the low oil pressure limiting line is opened, the high oil pressure limiting line is closed, and the low pressure oil line is unobstructed to compress hydrogen to 20MPa bottle group for storage.

The advantages of the control method over the prior art are the same as those of the above-mentioned oil pressure limiting system of the hydrogen diaphragm compressor, which will not be repeated here.

Detailed ways

The technical solutions of the present invention will be clearly and completely described below, and obviously, the described embodiments are part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

It should be noted that the terms "first" and "second" in the description and claims of the present invention are used to distinguish similar objects, but not necessarily used to describe a specific order or sequence. It should be understood that the data so used may be interchanged under appropriate circumstances such that the embodiments of the invention described herein can be practiced in sequences other than those described herein.

In the description of the present invention, it should be noted that, unless otherwise clearly stipulated and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense. Detachable connection, or integral connection; it can be mechanical connection or electrical connection; it can be direct connection or indirect connection through an intermediary, or it can be the internal communication of two components, it can be wireless connection, or it can be wired connection. Those of ordinary skill in the art can understand the specific meanings of the above terms in the present invention in specific situations.

An embodiment of the present invention provides an oil pressure limiting system for a hydrogen diaphragm compressor. limit line 6,

Wherein, in the embodiment of the present invention, the oil injection pipeline 1 has an oil inlet and an oil discharge port, and one side wall of the oil injection pipeline 1 is also provided with an oil replenishment port and an oil return port,

The diaphragm compressor 2 includes a membrane head oil chamber 21 , a middle body 22 and a crankcase 23 connected in sequence, and a crankshaft 231 is arranged in the crankcase 23 .

The gear box 3 is provided with a gear pump 31 and a relief valve 32. The inlet of the gear pump 31 is connected to the oil pool of the crankcase 23, and the outlet is connected to the oil return port of the oil injection pipeline 1. The overflow valve 32 One end of one end communicates with the oil outlet of gear pump 31, and the other end communicates with the oil sump of crankcase 23;

Oil supply pipeline 4, one end of which is connected with the oil supply port of oil injection pipeline 1, and the other end is connected with membrane head oil cavity 21, and oil supply pipeline 4 is provided with a filter 41, a first check valve 42, a plunger in sequence Pump 43 and the second check valve 44, after the hydraulic oil is pressurized by the plunger pump 43, oil is supplied to the membrane head oil chamber 21 through the second check valve 44;

Lubricating oil passage 5, one end of lubricating oil passage 5 is connected with filter 41, and the other end is connected with crankshaft 231;

Oil pressure limiting pipeline 6, one end of which communicates with membrane head oil chamber 21, and the other end communicates with the oil pool of crankcase 23, oil pressure limiting pipeline 6 is electrically connected with diaphragm compressor 2, so as to be suitable for storage The different pressure ranges of the hydrogen tank correspond to the connection of the high and low oil pressure restriction pipelines.

Therefore, limited by the characteristics of the diaphragm compressor, when the hydrogen inlet pressure is maintained at 5-20MPa, the long-tube trailer can only use hydrogen from 20MPa to about 6MPa, and there is still a large proportion of hydrogen that cannot be used effectively. By increasing the compressor compression The number of stages corresponds to the increase of the oil pressure limiting system of the compressor, which can make the hydrogen used by the hydrogen long tube trailer to about 1MPa, which greatly improves the utilization rate and reduces the cost.

It should be noted that the diaphragm compressor is driven by the motor, the crankshaft is rotated through the V pulley, and the piston in the oil cylinder is reciprocated and linearly moved through the connecting rod to push the oil, so that the diaphragm reciprocates and vibrates. Under control, every time the diaphragm vibrates, it completes a suction and exhaust process. When the membrane press is working, a small amount of oil in the oil cylinder leaks into the crankcase through the gap between the piston ring, the cylinder wall and the ring groove. In order to compensate for this part of the oil volume, the diaphragm can be close to the surface of the cylinder head at the end of the compression stroke, and the compressed medium is drained. The compensation oil pump injects oil into the oil cylinder during the suction stroke of the membrane compressor, and the oil volume is slightly more than the leakage. At the end of the compression stroke, the excess oil flows back to the crankcase through the pressure regulating valve that controls the oil pressure.

Specifically, in the embodiment of the present invention, the oil pressure limiting pipeline 6 includes a high oil pressure limiting pipeline 61 and a low oil pressure limiting pipeline 62 connected in parallel, and the high oil pressure limiting pipeline 61 is suitable for the hydrogen storage tank The inlet pressure range is opened under the condition of 5-20Mpa, and the low oil pressure restriction pipeline 62 is suitable for opening when the inlet pressure range of the hydrogen storage tank is 1-5Mpa.

Thus, the pressure of 5-20MPa TT truck interlocks with the high-pressure oil pressure limiter, the cut-off valve opens, the high-pressure oil circuit is unobstructed (the low-pressure oil circuit is cut off), and the hydrogen is compressed to 45MPa bottle group for storage; while the pressure of 1-5MPa TT car is linked Lock the low-pressure oil pressure limiter, open the cut-off valve, and unblock the low-pressure oil circuit (cut off the high-pressure oil circuit) to compress the hydrogen to 20MPa bottle group for storage.

Specifically, in the embodiment of the present invention, the high oil pressure limiting pipeline 61 includes a high pressure solenoid valve 611, a high oil pressure limiter 612 and a first pressure transmitter 613 connected in sequence, the high pressure solenoid valve 611 and the diaphragm compressor 2 are electrically connected, and the oil pressure setting range of the high-pressure solenoid valve 611 is 48-50Mpa. As the best preferred mode of this embodiment, the oil pressure of the high-pressure solenoid valve 611 is set at 49Mpa.

Specifically, in the embodiment of the present invention, the low oil pressure limiting pipeline 62 includes a low pressure solenoid valve 621, a low oil pressure limiter 622 and a second pressure transmitter 623 connected in sequence, the low pressure solenoid valve 621 and the diaphragm compressor 2 are electrically connected, and the oil pressure setting range of the low-pressure solenoid valve 621 is 5-7Mpa. As the best preferred mode of this embodiment, the oil pressure of the low-pressure solenoid valve 621 is set at 6Mpa.

Thus, during compression, excess hydraulic oil needs to be drained out of the compressor in order not to create an overpressure inside the compressor. This function is performed by the oil pressure limiter, through which excess lubricating oil flows back into the crankcase.

Specifically, in the embodiment of the present invention, a safety valve 7 is also connected between the outlet of the gear pump 31 and the crankcase 23, and the pressure preset value of the safety valve is not more than 5.5MPa, so as to be suitable for adjusting the pressure of the gear pump 31. pressure.

Specifically, in the embodiment of the present invention, a heater 232 is also provided in the oil sump of the crankcase 23 to be suitable for heating the hydraulic oil when the diaphragm compressor 2 stops, so that the hydraulic oil of the diaphragm compressor 2 maintains a certain temperature. .

Specifically, in the embodiment of the present invention, a third check valve 8 is provided in the oil supply line 4 near the membrane head oil chamber 21 . Thus, the setting of the third check valve 8 can further prevent the hydraulic oil from flowing back.

Specifically, in the embodiment of the present invention, the gear pump 31 is driven by a separate motor.

During the suction process of each stroke, the compensation pump replenishes excess hydraulic oil to the oil pump. This part of hydraulic oil can ensure that the diaphragm can fully contact the air disc at the end of compression.

The embodiment of the present invention also provides a control method of the oil pressure limiting system of the hydrogen diaphragm compressor, using the above-mentioned oil pressure limiting system of the hydrogen diaphragm compressor, the control method specifically includes:

S1: According to the pressure range of the hydrogen storage tank of the TT vehicle, judge whether it is necessary to replenish oil;

S2: If oil replenishment is required, interlock the hydrogen diaphragm compressor according to the pressure range of the hydrogen storage tank, and open the high oil pressure limiting line 61 or the low oil pressure limiting line 62;

S3: Open the oil supply line 4, start the gearbox 3, and the hydrogen diaphragm compressor starts to replenish oil, overflow oil, and realize the compression of hydrogen in the hydrogen storage tank; if oil replenishment is not required, start the hydrogen diaphragm compressor directly;

S4: After oil replenishment is completed, disconnect the first check valve 42 and the second check valve 44, open the overflow valve 32 and the safety valve 7, and enter the pre-operation stage of the hydrogen diaphragm compressor;

S5: After the pre-operation is completed and the motor reaches normal speed, close the high-pressure solenoid valve 611 and the low-pressure solenoid valve 521, disconnect the oil supply line 4, and the compressor enters the working state.

The advantages of the operation control method over the prior art are the same as those of the above-mentioned oil pressure limiting system of the hydrogen diaphragm compressor, and will not be repeated here.

Specifically, in step S2, the controlled interlocks the hydrogen diaphragm compressor according to the pressure range of the hydrogen storage tank, and opens the high oil pressure limiting pipeline 61 or the low oil pressure limiting pipeline 62, specifically including:

S21: When the inlet pressure range of the hydrogen storage tank is 5-20Mpa, the high oil pressure limiting line 61 is opened, the low oil pressure limiting line 62 is closed, and the high pressure oil line is unobstructed to compress the hydrogen to 45MPa bottle group for storage;

S22: When the inlet pressure range of the hydrogen storage tank is 1-5Mpa, the low oil pressure limiting line 62 is opened, the high oil pressure limiting line 61 is closed, and the low pressure oil line is unobstructed to compress the hydrogen to 20MPa for storage.

Although the present disclosure is based on the above, the protection scope of the present disclosure is not limited thereto. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the present disclosure, and these changes and modifications will all fall within the protection scope of the present invention.

Claims (10)

1. An oil pressure limiting system of a hydrogen diaphragm compressor, characterized in that it comprises: an oil injection line (1), which has an oil inlet, an oil discharge port, and one side of the oil injection line (1) is also provided with The oil supply port and the oil return port, the diaphragm compressor (2), including the membrane head oil chamber (21), the middle body (22) and the crankcase (23) connected in sequence, and the crankcase (23) is provided with a crankshaft (231); gear box (3), gear pump (31) and relief valve (32) are provided in the gear box (3), the inlet of the gear pump (31) is connected with the crankcase (23) The oil pool is connected, the outlet is connected with the oil return port of the oil injection pipeline (1), one end of the overflow valve (32) is connected with the oil outlet of the gear pump (31), and the other end is connected with the oil outlet of the gear pump (31). The oil sump of the crankcase (23) is connected; one end of the oil supply line (4) is connected with the oil supply port of the oil injection line (1), and the other end is connected with the oil chamber (21) of the membrane head , a filter (41), a first check valve (42), a plunger pump (43) and a second check valve (44) are arranged in sequence on the oil supply line (4), and the hydraulic oil passes through the After the plunger pump (43) is pressurized, oil is supplied to the membrane head oil chamber (21) through the second check valve (44); the lubricating oil circuit (5), the lubricating oil circuit (5) One end is connected with the filter (41), the other end is connected with the crankshaft (231); the oil pressure limiting pipeline (6), one end is connected with the membrane head oil cavity (21), and the other end is connected with the The oil pool of the crankcase (23) is connected, and the oil pressure limiting pipeline (6) is electrically connected with the diaphragm compressor (2), so as to be suitable for connecting high and low oil for different pressure ranges of the hydrogen storage tank. pressure limiting line. 2. The oil pressure limiting system of hydrogen diaphragm compressor according to claim 1, characterized in that, the oil pressure limiting pipeline (6) comprises a high oil pressure limiting pipeline (61) and a low oil pressure pipeline connected in parallel Restricting pipeline (62), the high oil pressure limiting pipeline (61) is suitable for opening under the condition that the inlet pressure range of the hydrogen storage tank is 5-20Mpa, and the low oil pressure limiting pipeline (62) is suitable for The inlet pressure range of the hydrogen storage tank is opened at 1-5Mpa. 3. The oil pressure limiting system of hydrogen diaphragm compressor according to claim 2, characterized in that, the high oil pressure limiting pipeline (61) comprises a high pressure solenoid valve (611) connected in sequence, a high oil pressure limiter (612) and the first pressure transmitter (613), the high-pressure solenoid valve (611) is electrically connected to the diaphragm compressor (2), and the oil pressure setting range of the high-pressure solenoid valve (611) It is 48-50Mpa. 4. The oil pressure limiting system of hydrogen diaphragm compressor according to claim 1, characterized in that, the low oil pressure limiting pipeline (62) comprises a low pressure solenoid valve (621) connected in sequence, a low oil pressure limiter (622) and the second pressure transmitter (623), the low pressure solenoid valve (621) is electrically connected with the diaphragm compressor (2), and the oil pressure setting range of the low pressure solenoid valve (621) It is 5-7Mpa. 5. The oil pressure limiting system of hydrogen diaphragm compressor according to claim 1, characterized in that a safety valve (7) is also connected between the outlet of the gear pump (31) and the crankcase (23) , the pressure preset value of the safety valve is not greater than 5.5MPa, so as to be suitable for adjusting the pressure of the gear pump (31). 6. The oil pressure limiting system of hydrogen diaphragm compressor according to claim 1, characterized in that, a heater (232) is also provided in the oil pool of the crankcase (23), so as to be suitable for compressing the diaphragm When the machine (2) stops, the hydraulic oil is heated, so that the hydraulic oil of the diaphragm compressor (2) maintains a certain temperature. 7. The oil pressure limiting system of a hydrogen diaphragm compressor according to claim 1, wherein a third check valve ( 8). 8. The oil pressure limiting system of a hydrogen diaphragm compressor according to claim 1, characterized in that the gear pump (31) is driven by a separate motor. 9. A method for controlling the oil pressure limiting system of a hydrogen diaphragm compressor, characterized in that the oil pressure limiting system of the hydrogen diaphragm compressor described in any one of claims 1-8 is adopted, and the control method specifically comprises: S1: According to the pressure range of the hydrogen storage tank of the TT vehicle, judge whether it is necessary to replenish oil; S2: If oil replenishment is required, interlock the hydrogen diaphragm compressor according to the pressure range of the hydrogen storage tank, and open the high oil pressure limiting pipeline (61) or the low oil pressure limiting pipeline (62); S3: Open the oil supply line (4), start the gearbox (3), and the hydrogen diaphragm compressor starts to replenish oil, overflow oil, and realize the compression of hydrogen in the hydrogen storage tank; if oil replenishment is not required, directly start the hydrogen diaphragm compression machine; S4: After oil replenishment is completed, disconnect the first check valve (42) and the second check valve (44), open the overflow valve (32) and safety valve (7), and enter the pre-operation stage of the hydrogen diaphragm compressor ; S5: After the pre-run is completed and the motor reaches normal speed, close the high-pressure solenoid valve (611) and the low-pressure solenoid valve (521), disconnect the oil supply line (4), and the compressor enters the working state. 10. The control method of the hydrogen diaphragm compressor oil pressure limiting system according to claim 9, characterized in that, in step S2, the controlled hydrogen diaphragm compressor is interlocked according to the pressure range of the hydrogen storage tank, and the high oil pressure is turned on. Restriction line (61) or low oil pressure restriction line (62), including: S21: When the inlet pressure range of the hydrogen storage tank is 5-20Mpa, the high oil pressure limiting line (61) is opened, the low oil pressure limiting line (62) is closed, and the high pressure oil line is smooth to compress the hydrogen to 45MPa bottle group storage; S22: When the inlet pressure range of the hydrogen storage tank is 1-5Mpa, the low oil pressure limiting line (62) is opened, the high oil pressure limiting line (61) is closed, and the low pressure oil line is smooth to compress the hydrogen to 20MPa Bottle group storage.