A supersonic ejector booster device with ultra-high compression ratio based on hierarchical control

Abstract

The present invention relates to the technical field of fluid supercharging for internal combustion engines, and particularly relates to a super-high compression ratio ejector supercharging device based on hierarchical regulation. It includes: a main flow system, a hierarchical regulation ejector flow system, and a controller; the main flow system includes: a pressure regulating skid of the main flow system receives the initial high-pressure gas in the upstream pipeline, reduces the pressure to obtain medium-pressure gas, and transports the medium-pressure gas to the supercharging device; the supercharging device pressurizes the medium-pressure gas into high-pressure gas and sends it to the downstream pipeline; the hierarchical regulation ejector flow system includes: ejectors of multiple levels and corresponding high-pressure regulating valves, low-pressure check valves, medium-pressure regulating valves, and pressure sensors for each level of ejector, constituting a regulating ejector flow system corresponding to multiple levels; the device proposed by the present invention can recover the gas fluid discharged by the supercharging device, pressurize it and reinject it into the inlet of the supercharging device for reuse, thereby more effectively utilizing the energy of the working fluid, improving the overall efficiency, and realizing the fluid recovery with a super-high compression ratio.

Description

Technical Field

[0001] The present invention relates to the technical field of fluid supercharging for internal combustion engines, and particularly relates to a super high compression ratio ejector supercharging device based on hierarchical regulation. Background Art

[0002] In a gas fluid transportation system, a supercharging device is a key component for achieving efficient gas fluid transportation. Its working principle is similar to the supercharging technology of internal combustion engines. For example, an internal combustion engine increases the intake pressure through turbocharging or mechanical supercharging to enhance combustion efficiency. The supercharging device in the gas transportation system also achieves more efficient transportation by increasing the gas pressure. However, under high-pressure transportation conditions, due to the limitations of the sealing system, the problem of gas fluid leakage is inevitable. This not only causes energy waste but also may lead to environmental pollution. Therefore, an advanced exhaust gas recirculation system is adopted in internal combustion engines to minimize leakage losses by introducing gas fluid recovery and reuse. This technological improvement can not only significantly improve energy utilization efficiency but also bring considerable economic and environmental benefits.

[0003] In current gas fluid recovery technologies, there is a method of first recovering the vented gas fluid with a gas holder and then transporting it to other places for treatment such as combustion, compression, or liquefaction using other processes. This requires additional storage space, increases transportation costs, and the gas fluid cannot be directly reused in the original system. There is also a method of using the mechanical energy output by an expander as power to supercharge the vented gas fluid and then input it into the main pipeline system. This requires first converting the pressure energy of high-pressure gas fluid into mechanical energy through an expander and then using the mechanical energy as the pressure energy for recovering the vented gas fluid. The process is complex and requires additional machinery to achieve energy conversion. There is also a method of using a reciprocating compressor to supercharge the vented gas fluid and reinject it into the inlet of the supercharging device. However, a reciprocating compressor is a high-speed rotating machine that requires additional electrical energy, and there are many vulnerable parts in the reciprocating machine, increasing additional costs.

[0004] In addition to the above several technologies, the ejector technology uses a very small part of the fluid in the main pipeline system as the motive fluid to suck the vented fluid, supercharge it, and then inject it into the inlet of the supercharging device, the branch outlet, or the fuel pipe. The ejector device is used more frequently due to its simplicity and cost-effectiveness. The ejector device has no rotating equipment, no vulnerable parts, does not consume electrical energy, only adds corresponding pipelines, occupies a small space, and can achieve supercharging of low-pressure gas fluid by utilizing the mutual conversion of pressure energy. However, generally, the supercharging capacity of a single-stage ejector flow system is limited and it is difficult to achieve super high compression ratio fluid recovery. Summary of the Invention

[0005] To solve the problems existing in the prior art, the present invention provides an ejector supercharging device with ultra-high compression ratio based on hierarchical regulation. The device includes: a main flow system, a hierarchical regulation ejector flow system, and a controller; the main flow system includes: the main flow system pressure regulating skid receives the initial high-pressure gas in the upstream pipeline, reduces the pressure to obtain medium-pressure gas, and transports the medium-pressure gas to the supercharging device; the supercharging device pressurizes the medium-pressure gas into high-pressure gas and sends it to the downstream pipeline; the hierarchical regulation ejector flow system includes: ejectors of multiple levels and corresponding high-pressure regulating valves, low-pressure check valves, medium-pressure regulating valves, and pressure sensors for each level of ejector, constituting a regulating ejector flow system corresponding to multiple levels; the device proposed by the present invention can recover the gas fluid discharged from the supercharging device, pressurize it and reinject it into the inlet of the supercharging device for reuse, thereby more effectively utilizing the energy of the working fluid, improving the overall efficiency, and realizing the fluid recovery with ultra-high compression ratio.

[0006] The present invention adopts the following technical solutions. An ejector supercharging device with ultra-high compression ratio based on hierarchical regulation includes: a main flow system, a hierarchical regulation ejector flow system, and a controller;

[0007] The main flow system includes: a main flow system pressure regulating skid and a supercharging device;

[0008] The main flow system pressure regulating skid receives the initial high-pressure gas in the upstream pipeline, reduces the pressure to obtain medium-pressure gas, and transports the medium-pressure gas to the supercharging device; the supercharging device pressurizes the medium-pressure gas into high-pressure gas and sends it to the downstream pipeline;

[0009] The hierarchical regulation ejector flow system includes: ejectors of multiple levels and corresponding high-pressure regulating valves, low-pressure check valves, medium-pressure regulating valves, and pressure sensors for each level of ejector, constituting a regulating ejector flow system corresponding to multiple levels;

[0010] The high-pressure regulating valve is installed on the high-pressure inlet pipeline of the ejector, and is used to receive the initial high-pressure gas in the upstream pipeline and adjust the pressure to obtain the working gas of the ejector;

[0011] The low-pressure check valve is installed on the low-pressure inlet pipeline of the ejector, and is used to receive the working gas of the previous-level ejector as the entrained gas of the next-level ejector;

[0012] The ejector mixes the working gas and the entrained gas to form outlet medium-pressure gas;

[0013] The medium-pressure regulating valve is installed on the medium-pressure outlet pipeline of the ejector, and is used to adjust the pressure of the outlet medium-pressure gas and transport it to the supercharging device.

[0014] Further, the supercharging device pressurizes the medium-pressure gas into working high-pressure gas and sends it to the downstream pipeline, and further includes:

[0015] When the pressurization device pressurizes medium-pressure gas into high-pressure gas, part of the medium-pressure gas is vented by the pressurization device and converted into vented low-pressure gas;

[0016] The vented low-pressure gas is transmitted to the hierarchical regulation ejector system.

[0017] Further, the low-pressure check valve is installed on the low-pressure inlet pipeline of the ejector and is used to receive the working gas of the previous-stage ejector, including:

[0018] The low-pressure check valve corresponding to the first-stage ejector receives the vented low-pressure gas and serves as the entrained gas of the first-stage ejector;

[0019] The low-pressure check valve corresponding to the second-stage ejector receives the working gas of the first-stage ejector and serves as the entrained gas of the second-stage ejector;

[0020] It is received sequentially downwards until the entrained gas of the last-stage ejector is obtained.

[0021] Further, the number of levels of the hierarchical regulation ejector system is obtained according to the following method:

[0022] Obtain the pressure ratio of the high-pressure gas and the low-pressure gas in the main flow system to obtain the expansion ratio;

[0023] Obtain the pressure ratio of the medium-pressure gas and the low-pressure gas in the main flow system to obtain the compression ratio;

[0024] Select the number of levels of the regulation ejector system in the set parameter table according to the values of the expansion ratio and the compression ratio.

[0025] Further, the high-pressure regulating valve is installed on the high-pressure inlet pipeline of the ejector and is used to receive the initial high-pressure gas in the upstream pipeline and perform pressure regulation, including:

[0026] The high-pressure regulating valve corresponding to each level of ejector respectively receives the initial high-pressure gas in the upstream pipeline to obtain the working gas of each level of ejector.

[0027] Further, the controller uses a reduced-order surrogate model to control the high-pressure regulating valve, the low-pressure check valve, and the medium-pressure regulating valve in the hierarchical regulation ejector system.

[0028] Further, the reduced-order surrogate model is specifically:

[0029] According to the historical operation data of the main flow system, obtain the typical operation conditions in the historical operation data, the change rules between the vent flow rate and pressure of the gas seal gas and the operation conditions of the pressurization device;

[0030] Construct the reduced-order surrogate model based on a neural network and fit the reduced-order surrogate model according to the variation law.

[0031] Further, fitting the reduced-order surrogate model includes: taking the minimum injection pressure fluctuation, the minimum injection energy loss, and the stable operation of the pressurization device as the objectives, establishing a simulation model with the venting flow rate, pressure, and the structure of the hierarchical regulation injection flow system as the control objects, and obtaining the well-fitted reduced-order surrogate model.

[0032] The beneficial effects of the present invention are as follows: The present invention makes full use of the pressure difference formed by the main pipeline system when the high-pressure gas fluid from the upstream is reduced to the medium-pressure gas fluid suitable for the operation of the pressurization device through the pressure regulating skid. The gas energy wasted as heat energy due to frictional loss at the pressure regulating skid is utilized. When the flow rate of the high-pressure gas in the main pipeline system is generally large enough, according to the actual flow rate of the vent gas of the pressurization device for matching design, only a small part of the high-pressure gas flow rate is needed to realize the recovery of the vent gas, and the obvious effects brought are as follows:

[0033] In the hierarchical regulation injection flow system, the injection process is divided into multiple stages, and the fluid pressure is gradually increased at each stage. This way of gradually increasing the pressure can more effectively utilize the energy of the working fluid, reduce energy loss, and improve the overall efficiency;

[0034] Through gradually increasing the pressure, the energy of the working fluid is more fully utilized, and more kinetic energy is converted into pressure energy. Compared with the single-stage injection flow system, the multi-stage injection flow system has less loss in the energy conversion process, thereby improving the overall energy utilization rate. At the same time, the load of each stage of the injection flow system can be reduced, the pressure fluctuation and vibration of the system can be reduced, and the stability and operation efficiency of the system can be improved;

[0035] The controller designed by the present invention can solve the technical problems of precise design and control of the whole system, ensure the flow rate and pressure matching of each stage of the injection flow system, avoid the influence of flow imbalance or pressure fluctuation on the system, and form a control logic for safe and efficient operation under all working conditions. Thus, on the premise of ensuring the stable operation of the pressurization device, the vent gas can be recovered to the greatest extent. Through hierarchical regulation, the pressure of each stage of the injection flow system can be more precisely controlled, avoiding damage to the system caused by too high or too low pressure. Precise pressure control helps to extend the service life of the equipment and improve the reliability of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0037] Figure 1 Schematic structural diagram of a super-high compression ratio ejector booster device based on hierarchical regulation according to an embodiment of the present invention;

[0038] Figure 2 Schematic flow chart of a variable operating condition hierarchical coupling multi-objective coordinated control method for a hierarchical regulation ejector flow system according to an embodiment of the present invention;

[0039] Figure 3 Schematic structural diagram of a super-high compression ratio ejector booster device based on hierarchical regulation according to another embodiment of the present invention;

[0040] Wherein, 1 is the main flow system; 101 is the initial high-pressure gas in the upstream pipeline; 102 is the pressure regulating skid of the main flow system; 103 is the medium-pressure gas for the operation of the booster equipment; 104 is the booster equipment; 105 is the high-pressure gas in the downstream pipeline; 106 is the low-pressure gas discharged; 2 is the hierarchical regulation ejector flow system; 21 is the first-stage ejector flow system; 211 is the first-stage ejector; 212 is the first-stage high-pressure regulating valve; 213 is the first-stage low-pressure check valve; 214 is the first-stage medium-pressure regulating valve; 215 is the first-stage pressure sensor; 22 is the second-stage ejector flow system; 221 is the second-stage ejector; 222 is the second-stage high-pressure regulating valve; 223 is the second-stage low-pressure check valve; 224 is the second-stage medium-pressure regulating valve; 225 is the second-stage pressure sensor; 23 is the third-stage ejector flow system; 231 is the third-stage ejector; 232 is the third-stage high-pressure regulating valve; 233 is the third-stage low-pressure check valve; 234 is the third-stage medium-pressure regulating valve; 235 is the third-stage pressure sensor; 22-2(n - 1) is the 2nd to (n - 1)th stage ejector flow systems; 2n is the nth stage ejector flow system; 2n1 is the nth stage ejector; 2n2 is the nth stage high-pressure regulating valve; 2n3 is the nth stage low-pressure check valve; 2n4 is the nth stage medium-pressure regulating valve; 2n5 is the nth stage pressure sensor; 3 is the controller. Detailed implementation manners

[0041] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0042] A schematic flow chart of a super-high compression ratio ejector booster device based on hierarchical regulation according to an embodiment of the present invention is as Figure 1 shown, including: the main flow system 1, the hierarchical regulation ejector flow system 2 and the controller 3, specifically as follows:

[0043] The main pipeline system 1 includes the initial high-pressure gas 101 from the upstream pipeline, the pressure regulating skid 102 of the main pipeline system, the medium-pressure gas 103 for the operation of the boosting equipment, the boosting equipment 104, the high-pressure gas 105 of the downstream pipeline, and the vented low-pressure gas 106. The pressure regulating skid 102 of the main pipeline system receives the initial high-pressure gas 101 from the upstream pipeline for pressure reduction, thereby reducing the initial high-pressure gas 101 from the upstream pipeline to the medium-pressure gas 103 suitable for the operation of the boosting equipment subsequently, and delivering the medium-pressure gas 103 for the operation of the boosting equipment to the boosting equipment 104; the boosting equipment 104 pressurizes the medium-pressure gas 103 for the operation of the boosting equipment to the high-pressure gas 105 of the downstream pipeline and sends it to the downstream pipeline, and a small part of the gas leaks due to the gas seal of the boosting equipment and becomes unusable gas that can only be vented to become the low-pressure gas 106.

[0044] The hierarchical control ejector system 2 includes a first-stage ejector 211, a first-stage high-pressure regulating valve 212, a first-stage low-pressure check valve 213, and a first-stage medium-pressure regulating valve 214; Figure 1 It also includes the second-stage to the (n - 1)-stage ejector systems 22 - 2(n - 1), specifically: 2n, the n-stage ejector system; the n-stage ejector 2n1, the n-stage high-pressure regulating valve 2n2, the n-stage low-pressure check valve 2n3, the n-stage medium-pressure regulating valve 2n4, and the n-stage pressure sensor 2n5.

[0045] Table 1 Schematic table of matching selection of the number of stages of the hierarchical control ejector system

[0046] ;

[0047] In the embodiment of the present invention, the hierarchical control ejector system is formed by cascading one or several ejectors, forming the first-stage ejector system to the n-stage ejector system. The specific number of stages of the ejector pipeline required can be selected for matching through Table 1 according to the relationship between the expansion ratio (the pressure ratio of the high-pressure gas to the low-pressure gas) and the compression ratio (the pressure ratio of the medium-pressure gas to the low-pressure gas).

[0048] In the staged control ejector system 2 in the embodiments of the present invention, for the first-stage to the n-stage ejector systems, each includes an ejector, a high-pressure regulating valve, a low-pressure check valve, and a medium-pressure regulating valve at each stage; the ejectors at each stage use the high-pressure inlet gas at their respective stages to eject the low-pressure inlet gas and mix to form the outlet medium-pressure gas; taking the first-stage staged control ejector system 2 in the figure as an example, its connection form is that the first-stage high-pressure regulating valve 212 is at the high-pressure inlet pipeline of the first-stage ejector 211, and is used to receive the initial high-pressure gas 101 from the upstream pipeline and perform pressure regulation to obtain the working gas of the first-stage ejector 211; the first-stage low-pressure check valve 213 is at the low-pressure inlet pipeline of the first-stage ejector 211, and is used to receive the working gas of the previous-stage ejector as the entrained gas of the next-stage ejector; at the same time, it is used to prevent the backflow of low-pressure gas from affecting the normal operation of the main pipeline system pressurization equipment; among them, only the first-stage low-pressure check valve 213 directly receives the low-pressure gas 106 vented from the pressurization equipment 104 as the low-pressure entrained gas of the first-stage ejector. If there are subsequent stages, the low-pressure check valves of the subsequent stages sequentially receive the medium-pressure outlet gas from the previous-stage ejector pipeline as their own low-pressure entrained gas, and the sequential pressurization of the entire staged control ejector system is realized through such a connection form; the first-stage medium-pressure regulating valve 214 is at the medium-pressure outlet pipeline of the first-stage ejector 211, and is used to regulate the pressure of the outlet medium-pressure gas and transmit it to the pressurization equipment 104; the medium-pressure regulating valves at each level are all connected to the inlet of the pressurization equipment, so as to realize the reinjection of the pressurized vent gas and adjust the flow pressure of the medium-pressure gas at the outlet of each ejector according to the signal of the controller.

[0049] In the embodiments of the present invention, the controller 3 is equipped with a variable-condition staged coupling multi-objective coordinated control method for the staged control ejector system. First, by sorting out the working conditions, a process model is built to study the influence of changes, and then a reduced-order surrogate model of the staged control ejector system is constructed. Finally, online simulation is carried out to analyze the performance and effect of the control to complete the multi-objective coordinated control, so as to adjust the flow pressure of the medium-pressure gas at the outlet of each ejector. The specific flow schematic diagram is as Figure 2 shown, and specifically includes:

[0050] Sorting out the working conditions is: Based on the equipment resume and historical operation data of the main pipeline system and the pressurization equipment therein, the historical typical working conditions thereof, and the relationship between the gas seal gas vent flow rate and pressure and the operating conditions of the pressurization equipment are sorted out, and the venting law of the seal gas under the typical operating conditions of the gas pressurization equipment is summarized.

[0051] Building a process model to study the influence of changes is: Based on the process simulation model, study the change law between the gas seal gas vent flow rate and pressure and the rotational speed of the pressurization equipment under variable working conditions, as well as the influence law of the staged control ejector system on the working performance of the pressurization equipment.

[0052] The reduced-order surrogate model for constructing a hierarchical control ejector flow system is as follows: Based on a deep learning neural network, a reduced-order surrogate model for the hierarchical control ejector flow system is constructed. After determining the input and output parameters, a set of variables that best describe the characteristics of the model are obtained, thereby establishing a strong correlation mapping relationship between the parameters, and further improving the operation effect of the model. The total pressure and total temperature of the inlet and outlet fluids, as well as the maximum pressure gradient of the entire fluid domain, are selected as the input and output of the model to simulate the gas mixing process and reflect the working characteristics of the system. By simplifying the high-dimensional, high-fidelity model and retaining its main features, the reduced-order surrogate model can reduce the computational cost while maintaining sufficient accuracy. Furthermore, the neural network is used to capture the high-dimensional complex nonlinear relationship of the hierarchical control ejector flow system to generate an efficient surrogate model. In scenarios that require rapid response, the reduced-order surrogate model can provide approximate results to meet the real-time requirements.

[0053] Online simulation is as follows: Train the constructed reduced-order surrogate model of the hierarchical control ejector flow system to accurately determine the relationship between the venting flow rate, pressure, and the structure of the hierarchical control ejector flow system. Combining the actual operating conditions of the main pipeline system and the booster equipment therein, with the goals of minimizing the ejector pressure fluctuation, minimizing the ejector energy loss, and ensuring the stable operation of the booster equipment, establish a variable-condition hierarchical coupling multi-objective coordinated control method with the venting flow rate, pressure, and the structure of the hierarchical control ejector flow system as the control objects. By analyzing the online simulation effect and performance, the gas vented can be recovered to the greatest extent while ensuring the stable operation of the booster equipment.

[0054] In another specific embodiment of the present invention:

[0055] As Figure 3 shown, the present invention provides a super-high compression ratio ejector device based on hierarchical control, including a main pipeline system 1, a hierarchical control ejector flow system 2, and a controller 3, where:

[0056] The parameters of the main pipeline system 1 in this embodiment are from a certain site, including the initial high-pressure gas 101 from the upstream pipeline, the main pipeline system pressure regulating skid 102, the medium-pressure gas 103 for the booster equipment to work, the booster equipment 104, the high-pressure gas 105 going to the downstream pipeline, and the vented low-pressure gas 106.

[0057] In this embodiment, the initial high-pressure gas 101 from the upstream pipeline is the mass and energy source of the main pipeline system 1, and its pressure is 7 - 8 MPa; the pressure regulating skid 102 of the main pipeline system regulates and reduces the pressure of the initial high-pressure gas 101 from the upstream pipeline to the medium-pressure gas 103 suitable for the operation of the booster equipment in the subsequent stage, and the pressure of the medium-pressure gas after pressure reduction is 3.8 MPa; the booster equipment 104 pressurizes most of the medium-pressure gas after being reduced in pressure by the pressure regulating skid 102 of the main pipeline system into the high-pressure gas 105 going to the downstream pipeline, and a small part of the gas leaks due to the gas seal of the booster equipment 104 and becomes the gas that cannot be utilized and can only be vented as the low-pressure gas 106, and its pressure is 0.1 MPa.

[0058] According to the actual working conditions of the above-mentioned main pipeline system 1, in this embodiment, the expansion ratio and compression ratio of the staged control ejector system 2 are calculated. The expansion ratio is 70 and the compression ratio is 38. The matching selection of the number of stages of the staged control ejector system in this embodiment is carried out through Table 1, and it is thus obtained that 3-stage ejection is required to reach the target ejection pressure. Therefore, the staged control ejector system 2 in this embodiment is formed by cascading 3 ejectors, forming the first-stage ejector system 21, the second-stage ejector system 22, and the third-stage ejector system 23.

[0059] The first-stage ejector system 21 in this embodiment includes the first-stage ejector 211, the first-stage high-pressure regulating valve 212, the first-stage low-pressure check valve 213, and the first-stage medium-pressure regulating valve 214; the second-stage ejector system 22 includes the second-stage ejector 221, the second-stage high-pressure regulating valve 222, the second-stage low-pressure check valve 223, and the second-stage medium-pressure regulating valve 224; the third-stage ejector system 23 includes the third-stage ejector 231, the third-stage high-pressure regulating valve 232, the third-stage low-pressure check valve 233, and the third-stage medium-pressure regulating valve 234; the ejectors at all levels (the first-stage ejector 211, the second-stage ejector 221, the third-stage ejector 231) utilize the working gas and the ejector low-pressure inlet gas to mix and form the outlet medium-pressure gas; their connection form is that the high-pressure regulating valves at all levels (the first-stage high-pressure regulating valve 212, the second-stage high-pressure regulating valve 222, the third-stage high-pressure regulating valve 232) are respectively on the high-pressure inlet pipelines of the ejectors at all levels, the low-pressure check valves at all levels (the first-stage low-pressure check valve 213, the second-stage low-pressure check valve 223, the third-stage low-pressure check valve 233) are respectively on the low-pressure inlet pipelines of the ejectors at all levels, and the medium-pressure regulating valves at all levels (the first-stage medium-pressure regulating valve 214, the second-stage medium-pressure regulating valve 224, the third-stage medium-pressure regulating valve 234) are respectively on the medium-pressure outlet pipelines of the ejectors at all levels.

[0060] In this embodiment, the high-pressure regulating valves at all levels receive the initial high-pressure gas 101 from the upstream pipeline that is partially diverted from the main flow system 1, serving as the working gas for the ejectors at all levels, and adjusting the flow rate and pressure of the working gas for the ejectors at all levels according to the signals from the controller; the low-pressure check valves at all levels are used to prevent the backflow of low-pressure gas from affecting the normal operation of the pressurization equipment 104 in the main flow system; among them, only the first-stage low-pressure check valve 213 directly receives the low-pressure gas 106 discharged from the pressurization equipment 104 as the low-pressure entrained gas for the first-stage ejector 211; the second-stage low-pressure check valve 223 is connected to the first-stage medium-pressure gas boosted by the first-stage ejector 211 as the low-pressure entrained gas for the second-stage ejector 221; the third-stage low-pressure check valve 233 is connected to the second-stage medium-pressure gas boosted by the second-stage ejector 221 as the low-pressure entrained gas for the third-stage ejector 231, achieving the step-by-step pressurization of the entire hierarchical control ejector flow system 2 through such a connection form; the medium-pressure regulating valves at all levels are connected to the inlet of the pressurization equipment 104, thereby realizing the reinjection of the pressurized discharged gas and adjusting the flow rate and pressure of the medium-pressure gas at the outlet of the ejectors at all levels according to the signals from the controller.

[0061] In this embodiment, the first-stage ejector 211 uses the initial high-pressure gas 101 from the upstream pipeline at 7 MPa to entrain the low-pressure gas 106 discharged from the pressurization equipment 104 at 0.1 MPa to a first-stage medium-pressure gas pressure of 0.65 MPa; the second-stage ejector 221 uses the initial high-pressure gas 101 from the upstream pipeline at 7 MPa to entrain the first-stage medium-pressure gas boosted by the first-stage ejector 211 as the second-stage low-pressure gas at 0.65 MPa to a second-stage medium-pressure gas pressure of 2.4 MPa; the third-stage ejector 231 uses the initial high-pressure gas 101 from the upstream pipeline at 7 MPa to entrain the second-stage medium-pressure gas boosted by the second-stage ejector 221 as the third-stage low-pressure gas at 2.4 MPa to a medium-pressure gas 103 pressure of 3.8 MPa for the operation of the pressurization equipment 104.

[0062] The controller 3 is equipped with a variable-condition hierarchical coupling multi-objective coordinated control method for the hierarchical control ejector flow system. Based on the coupling and coordination characteristics between the gas flow rate, pressure of the main flow system 1 and the pressurization equipment 104 therein during operation, and the structure of the hierarchical control ejector flow system 2, a multi-parameter coordinated control with the objectives of minimizing the ejector pressure fluctuation, maximizing the residual gas recovery utilization rate, minimizing the ejector energy loss, and ensuring the stable operation of the pressurization equipment is established, realizing the precise modulation of the ejector fluid, solving the technical problems of the precise design and control of the entire system, and forming a full-condition safe and efficient operation control logic, thereby maximizing the recovery of the discharged gas on the premise of ensuring the stable operation of the pressurization equipment.

[0063] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims

1. An ultra-high compression ratio injection supercharging device based on graded regulation, characterized in that: include: Main flow system, graded control jet flow system and controller; The main flow system includes: a main flow system pressure regulating skid and a pressure boosting device; The main flow system pressure regulating skid receives the initial high-pressure gas in the upstream pipeline, reduces the pressure to obtain medium-pressure gas, and transmits the medium-pressure gas to the boosting device; the boosting device pressurizes the medium-pressure gas into high-pressure gas and sends it to the downstream pipeline; The hierarchical control ejection flow system comprises: ejectors of multiple levels and high-pressure control valves, low-pressure check valves, medium-pressure control valves and pressure sensors corresponding to ejectors of each level, forming a corresponding multiple-level control ejection flow system; The high-pressure regulating valve is installed in the high-pressure inlet pipeline of the ejector, and is used to receive the initial high-pressure gas in the upstream pipeline and perform pressure regulation to obtain the working gas of the ejector; The low-pressure check valve is installed in the low-pressure inlet pipe of the ejector, and is used to receive the outlet medium-pressure gas of the previous stage ejector as the ejected gas of the next stage ejector; The controller uses a reduced-order proxy model to control the high-pressure regulating valve, the low-pressure check valve and the medium-pressure regulating valve in the graded control injection flow system; The ejector mixes the working gas and the ejected gas to form outlet medium-pressure gas; The medium-pressure regulating valve is installed on the medium-pressure outlet pipeline of the ejector, and is used to adjust the pressure of the medium-pressure gas at the outlet and transmit it to the boosting equipment; The reduced-order proxy model is specifically: According to the historical operation data of the main flow system, obtain the typical operation conditions in the historical operation data, the change rules between the gas seal gas venting flow rate and pressure and the operation conditions of the boosting equipment; Constructing the reduced-order proxy model based on a neural network, and fitting the reduced-order proxy model according to the change rule; Among them, the reduced-order proxy model is fitted, including: with the goal of minimizing the injection pressure fluctuation, minimizing the injection energy loss and the stable operation of the boosting equipment, a simulation model with the venting flow, pressure and graded regulation of the injection flow system structure as the control object is established to obtain a fitted reduced-order proxy model.

2. The ultra-high compression ratio injection supercharging device based on graded regulation according to claim 1 is characterized in that: The boosting device pressurizes the medium-pressure gas into working high-pressure gas and sends it to the downstream pipeline, and also includes: When the boosting device pressurizes the medium-pressure gas into high-pressure gas, part of the medium-pressure gas is vented by the boosting device and converted into vented low-pressure gas; The vented low-pressure gas is transmitted to a staged control jet flow system.

3. The ultra-high compression ratio injection supercharging device based on graded regulation according to claim 2 is characterized in that: The low-pressure check valve is installed at the low-pressure inlet pipeline of the ejector and is used to receive the outlet medium-pressure gas of the previous ejector, and includes: The low-pressure check valve corresponding to the first-stage ejector receives the vented low-pressure gas as the ejected gas of the first-stage ejector; The low-pressure check valve corresponding to the second-stage ejector receives the outlet medium-pressure gas of the first-stage ejector as the ejected gas of the second-stage ejector; It is received downward in sequence until the ejected gas from the last stage ejector is obtained.

4. The ultra-high compression ratio injection supercharging device based on graded regulation according to claim 1 is characterized in that: The number of levels of the multiple-level regulating and ejecting flow system is obtained according to the following method: Obtain the pressure ratio of high-pressure gas to low-pressure gas in the main flow system to obtain the expansion ratio; Obtain the pressure ratio of the medium-pressure gas and the low-pressure gas in the main flow system to obtain the compression ratio; The number of levels for regulating the jet flow system is selected in the setting parameter table according to the values ​​of the expansion ratio and the compression ratio.

5. The ultra-high compression ratio injection supercharging device based on graded regulation according to claim 1 is characterized in that: The high-pressure regulating valve is installed on the high-pressure inlet pipeline of the ejector, and is used to receive the initial high-pressure gas in the upstream pipeline and perform pressure regulation, and includes: The high-pressure regulating valve corresponding to each level of ejector receives the initial high-pressure gas in the upstream pipeline respectively to obtain the working gas for each level of ejector.

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