LNG (Liquefied Natural Gas) electro-hydraulic dual-mode redundancy direct-drive piston type low-temperature booster pump

Abstract

The invention discloses an LNG electro-hydraulic dual-mode redundancy direct-drive piston type low-temperature booster pump, and relates to the technical field of low-temperature booster pumps. The low-temperature booster pump comprises a linear motor executing mechanism, a hydraulic executing mechanism and a heat exchanger. In a normal state, the LNG electro-hydraulic dual-mode redundancy direct-drive piston type low-temperature booster pump works in an independent driving state, namely, a linear motor executing mechanism works in an independent working mode, and at the moment, a three-position four-way electromagnetic valve of a hydraulic executing mechanism is located at the middle position; or the hydraulic actuating mechanism works independently, that is, the coil of the linear motor actuating mechanism is not electrified, and when the automobile needs higher power, the linear motor actuating mechanism and the hydraulic actuating mechanism can be matched for driving, that is, the linear motor actuating mechanism and the hydraulic actuating mechanism work at the same time, that is, the piston is driven electrically and hydraulically to do reciprocating rectilinear motion at the same time. According to the invention, electric drive and hydraulic drive can be independently driven or matched with each other, so that the functions of quick response and matched drive to increase power are realized.

Description

Technical Field

[0001] The present application belongs to the technical field of cryogenic booster pumps, and in particular, relates to an LNG electric-hydraulic dual-mode redundant direct-drive piston cryogenic booster pump. Background Art

[0002] Under the general trend of automobile energy transformation, natural gas vehicles have become the first choice of various alternative fuel vehicles due to their good emission characteristics and abundant fuel reserves. Major automobile manufacturers have also invested in the development of natural gas vehicles. Among them, liquefied natural gas (LNG) vehicles have become the mainstream direction of natural gas vehicle development due to their advantages such as high LNG energy density, convenient transportation, high emission performance, good safety performance, and recyclable cold energy.

[0003] The LNG vehicle gas supply system is one of the main components of LNG vehicles, mainly including special vehicle-mounted cryogenic insulation bottles, filling interfaces, LNG pumps, valves, LNG vaporizers, pressure displays and other components. Its basic function is to continuously and stably provide sufficient LNG fuel for the engine; LNG cryogenic booster pumps, as one of the main components of the LNG vehicle gas supply system, play a key role in the stable supply of LNG fuel. At present, the main boosting devices on the market are booster pumps, such as air-to-air booster pumps, pneumatic diaphragm pumps, plunger pumps, etc. These pumps have the following disadvantages: complex structure, complex operation, high manufacturing cost, and single driving mode. Summary of the invention

[0004] In order to overcome the shortcomings of the above-mentioned prior art, the purpose of this application is to provide an LNG electro-hydraulic dual-mode redundant direct-drive piston cryogenic booster pump, which can achieve the purpose of redundantly driving a cryogenic isobaric pump in multiple driving modes and has the advantages of simple structure and easy operation.

[0005] In order to achieve the above objectives, this application adopts the following technical solutions:

[0006] A LNG electro-hydraulic dual-mode redundant direct-drive piston type cryogenic booster pump comprises a linear motor actuator, a hydraulic actuator, a heat exchanger and a pump body.

[0007] Furthermore, the linear motor actuator includes a linear motor housing, a permanent magnet, a coil and a piston rod; the permanent magnet is installed in the linear motor housing; the coil is installed on the top of the piston rod; and the coil can drive the piston rod to achieve up and down reciprocating motion after being energized.

[0008] Furthermore, the hydraulic actuator includes a linear motor seat, a hydraulic cylinder housing, a hydraulic piston, a hydraulic piston seat and a hydraulic control pipeline; the hydraulic control pipeline includes a three-position four-way solenoid valve, a relief valve, a hydraulic pump check valve and a hydraulic pump; when the three-position four-way solenoid valve is in the left position or the right position, the hydraulic piston can drive the piston rod to achieve up and down reciprocating motion; when the three-position four-way solenoid valve is in the middle position, the hydraulic cylinder housing moves in the direction of the force under the action of external force, and the hydraulic pump is unloaded through the relief valve.

[0009] Furthermore, the pump body includes a piston rod sleeve, a pump body seat, a pump body shell, a pump body piston and a liquid circuit; the liquid circuit includes an LNG inlet check valve, a filter, an LNG storage tank, an LNG transportation pipeline and an LNG outlet check valve; when the piston rod moves upward, the LNG inlet check valve opens, the LNG outlet check valve closes, and the LNG liquid enters the pump body from the LNG storage tank; when the piston cylinder moves downward, the LNG inlet check valve closes, the LNG outlet check valve opens, and the LNG liquid enters the LNG transportation pipeline from the pump body.

[0010] Furthermore, the heat exchanger includes a heat exchange flow channel, a heat exchanger shell, an LNG output end, a heat exchanger medium input end and a heat exchanger medium output end; the LNG compressed liquid enters the heat exchange flow channel from the LNG transportation pipeline, and is vaporized into combustible LNG gas through heat exchange with the heat exchanger medium, and is output from the LNG output end to the inside of the automobile engine.

[0011] Compared with the prior art, the LNG electro-hydraulic dual-mode redundant direct-drive piston cryogenic booster pump provided in this application has the following beneficial effects:

[0012] (1) The electric part is directly driven by a linear motor, with fast response and simple transmission mechanism.

[0013] (2) Simple operation, easy maintenance and high control accuracy.

[0014] (3) The electro-hydraulic drive part of the present application integrates the concepts of "distributed multi-power" and "safety redundancy". The linear motor actuator and the hydraulic actuator can work in coordination with each other, or one can work while the other is pending. When a fault occurs in the linear motor actuator structure, it can be controlled by the hydraulic actuator; when a fault occurs in the hydraulic actuator, it can be controlled by the linear motor actuator structure without affecting the operation of the entire actuator. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is an overall schematic diagram of this application.

[0016] Figure 2 It is a structural diagram of a linear motor actuator.

[0017] Figure 3 It is a structural diagram of the heat exchanger.

[0018] Description of the numbers in the figure:

[0019] Linear motor actuator 100, hydraulic actuator 200, heat exchanger 300, pump body 400, linear motor housing 1, permanent magnet 2, coil 3, piston rod 4, linear motor seat 5, hydraulic cylinder housing 6, hydraulic piston 7, hydraulic piston seat 8, three-position four-way solenoid valve 9, relief valve 10, hydraulic pump check valve 11, hydraulic pump 12, heat exchange flow channel 13, heat exchanger housing 14, LNG output end 15, heat exchanger medium input end 16, heat exchanger medium output end 17, piston rod sleeve 18, pump body seat 19, pump body housing 20, pump body piston 21, LNG liquid inlet check valve 22, filter 23, LNG storage tank 24, LNG transportation pipeline 25, LNG liquid outlet check valve 26. DETAILED DESCRIPTION

[0020] The present application is further described in detail below in conjunction with the accompanying drawings.

[0021] Reference Figure 1 , an LNG electro-hydraulic dual-mode redundant direct-drive piston cryogenic booster pump, comprising a linear motor actuator 100, a hydraulic actuator 200, a heat exchanger 300 and a pump body 400. Among them, the hydraulic circuit of the hydraulic actuator is indicated by a hydraulic circuit control pipeline 500.

[0022] Reference Figure 1 and Figure 2 The linear motor actuator 100 includes a linear motor housing 1, a permanent magnet 2, a coil 3 and a piston rod 4. The permanent magnet 2 is installed in the linear motor housing. The coil 3 is installed on the top of the piston rod 4. When the coil 3 is energized, due to the presence of the permanent magnet 2, the coil 3 is acted upon by a force, driving the piston rod 4 to achieve up and down reciprocating motion.

[0023] Reference Figure 1 The hydraulic actuator 200 includes a linear motor seat 5, a hydraulic cylinder housing 6, a hydraulic piston 7, a hydraulic piston seat 8 and a hydraulic control pipeline 500, wherein the hydraulic control pipeline 500 includes a three-position four-way solenoid valve 9, a relief valve 10, a hydraulic pump check valve 11 and a hydraulic pump 12. When working, the three-position four-way solenoid valve 9 works in the left position or the right position, and drives the piston rod 4 to move up and down through the hydraulic piston 7. When the three-position four-way solenoid valve 9 is in the middle position, the internal pipeline of the hydraulic cylinder is connected, and the piston rod 4 can move in the direction of the force under the action of the external force; the hydraulic pump 12 can also be unloaded through the relief valve 10 at this time to prevent failure.

[0024] Reference Figure 1 and Figure 3The heat exchanger 300 includes a heat exchange flow channel 13, a heat exchanger shell 14, an LNG output end 15, a heat exchanger medium input end 16, and a heat exchanger medium output end 17. LNG compressed liquid enters the heat exchange flow channel 13 from the LNG transport pipeline 25, and is gasified into LNG gas that can be burned through heat exchange with the heat exchanger medium, and is output from the LNG output end 15 to the inside of the automobile engine.

[0025] Reference Figure 1 The pump body 400 includes a piston rod sleeve 18, a pump body seat 19, a pump body shell 20, a pump body piston 21 and a liquid circuit. The liquid circuit includes an LNG inlet check valve 22, a filter 23, an LNG storage tank 24, an LNG transportation pipeline 25 and an LNG outlet check valve 26. When the piston cylinder 4 moves upward, the LNG inlet check valve 22 opens, the LNG outlet check valve 26 closes, and the LNG liquid enters the pump body from the LNG storage tank 24. When the piston cylinder 4 moves downward, the LNG inlet check valve 22 closes, the LNG outlet check valve 26 opens, and the LNG liquid enters the LNG transportation pipeline 25 from the pump body.

[0026] The working principle of this application is:

[0027] The booster pump is driven by a linear motor actuator 100 and a hydraulic actuator 200 respectively. The booster pump can realize at least the following three working modes through different combinations of the two driving modes:

[0028] (1) The linear motor actuator 100 works alone (the three-position four-way solenoid valve 9 of the hydraulic actuator 200 is in the middle position):

[0029] When the coil 3 is energized, due to the presence of the permanent magnet 2 , the coil 3 is acted upon by electromagnetic force, thereby driving the piston rod 4 to achieve up and down reciprocating motion.

[0030] (2) Hydraulic actuator 200 single working mode (the coil of linear motor actuator 100 is not energized):

[0031] When working, the three-position four-way solenoid valve 9 works in the left position or the right position, and drives the piston rod 4 to move up and down through the hydraulic piston 7. When the three-position four-way solenoid valve 9 is in the middle position, the internal pipeline of the hydraulic cylinder is connected, and the piston rod 4 can move in the direction of the force under the action of the external force; the hydraulic pump 12 can also be unloaded through the relief valve 10 at this time to prevent malfunction.

[0032] (3) The working mode in which the linear motor actuator 100 and the hydraulic actuator 200 work simultaneously (electric and hydraulic actuators simultaneously drive the piston rod 4 to perform reciprocating linear motion):

[0033] The linear motor and the hydraulic pump are controlled simultaneously to realize the simultaneous up and down reciprocating control of the piston rod 4. In this working mode, the LNG electro-hydraulic dual-mode redundant direct-drive piston cryogenic booster pump will reach the maximum power.

Claims

1. An LNG electro-hydraulic dual-mode redundant direct-drive piston cryogenic booster pump, characterized in that: It includes a linear motor actuator, a hydraulic actuator, a heat exchanger and a pump body.

2. The LNG electric-hydraulic dual-mode redundant direct-drive piston cryogenic booster pump according to claim 1 is characterized in that: The linear motor actuator comprises a linear motor housing, a permanent magnet, a coil and a piston rod; the permanent magnet is installed in the linear motor housing; the coil is installed on the top of the piston rod; and the coil can drive the piston rod to achieve up and down reciprocating motion after being energized.

3. The LNG electric-hydraulic dual-mode redundant direct-drive piston cryogenic booster pump according to claim 2 is characterized in that: The hydraulic actuator includes a linear motor seat, a hydraulic cylinder housing, a hydraulic piston, a hydraulic piston seat and a hydraulic control pipeline; the hydraulic control pipeline includes a three-position four-way solenoid valve, a relief valve, a hydraulic pump check valve and a hydraulic pump; when the three-position four-way solenoid valve is in the left position or the right position, the hydraulic piston can drive the piston rod to achieve up and down reciprocating motion; when the three-position four-way solenoid valve is in the middle position, the hydraulic cylinder housing moves in the direction of the force under the action of external force, and the hydraulic pump is unloaded through the relief valve.

4. The LNG electric-hydraulic dual-mode redundant direct-drive piston cryogenic booster pump according to claim 3 is characterized in that: The pump body includes a piston rod sleeve, a pump body seat, a pump body shell, a pump body piston and a liquid circuit; the liquid circuit includes an LNG inlet check valve, a filter, an LNG storage tank, an LNG transportation pipeline and an LNG outlet check valve; when the piston rod moves upward, the LNG inlet check valve opens, the LNG outlet check valve closes, and LNG liquid enters the pump body from the LNG storage tank; when the piston cylinder moves downward, the LNG inlet check valve closes, the LNG outlet check valve opens, and LNG liquid enters the LNG transportation pipeline from the pump body.

5. The LNG electric-hydraulic dual-mode redundant direct-drive piston cryogenic booster pump according to claim 4 is characterized in that: The heat exchanger includes a heat exchange flow channel, a heat exchanger shell, an LNG output end, a heat exchanger medium input end and a heat exchanger medium output end; LNG compressed liquid enters the heat exchange flow channel from the LNG transportation pipeline, and is gasified into combustible LNG gas through heat exchange with the heat exchanger medium, and is output from the LNG output end to the inside of the automobile engine.

Images