Ship LNG methanol dual-fuel intelligent switching control method

Abstract

The invention discloses a ship LNG methanol dual-fuel intelligent switching control method, relates to the technical field of ship fuel switching control, and solves the problems that the current ship fuel switching judgment only depends on whether the ship fuel is located in a discharge forbidding area or not, and the concentration of residual fuel in a pipeline is lacked to be monitored in real time during ship fuel switching. The method comprises the following steps: obtaining a signal type of a fuel switching signal of a ship according to real-time navigation data; the external environment of the ship is obtained through analysis according to the real-time navigation data, and whether the ship meets pipeline purging conditions or not is judged based on the external environment; methanol use data and liquefied natural gas use data of fuel in the ship and pipeline use data of the ship are obtained, meanwhile, inert gas is controlled to purge a main input pipeline in the ship, and a pipeline purge completion instruction is obtained through purge; whether the fuel switching control of the ship is qualified or not is judged on the basis of the real-time working data, the fuel pipeline of the ship is swept in the fuel switching process, and the qualification rate of fuel switching of the ship is guaranteed.

Description

Technical Field

[0001] The present invention belongs to the technical field of ship fuel switching control, and in particular to a ship LNG methanol dual-fuel intelligent switching control method. Background Art

[0002] A marine dual-fuel system is a power configuration technology that allows the same main engine to flexibly switch between two fuels of different physical properties, typically liquefied natural gas (LNG) and methanol, marine diesel, or heavy fuel oil. The system integrates dual independent fuel supply lines, dedicated injectors, valves, and pre-treatment devices on the engine side. Through an electronic control unit (ECU) and DCS / PLC control logic, it performs a series of automated operations, including purging, preheating / precooling, injection, and ignition. This allows ships to meet the strict limits of emission control areas while achieving an optimal balance between operating costs and environmental performance based on fuel market price fluctuations and inventory levels. Technically, it balances combustion efficiency, safety redundancy, and system reliability, ensuring smooth and reliable fuel switching in all sea conditions and at all speeds. In existing technologies, determining whether a ship needs to initiate a fuel switch depends solely on whether the ship is in a no-discharge zone, ignoring the ship's power load requirements. This can lead to power fluctuations during fuel switching. Furthermore, when switching fuels, the purge of residual fuel in the pipeline relies on increasing or decreasing the inert gas flow rate, lacking real-time monitoring of the remaining fuel concentration in the pipeline. This can easily lead to residual fuel co-combustion and hydrate blockage. To this end, the present invention proposes an intelligent switching control method for LNG-methanol dual-fuel on ships. Summary of the Invention

[0003] The purpose of the present invention is to propose a ship LNG methanol dual fuel intelligent switching control method to solve the problems raised in the above background technology.

[0004] The technical problems to be solved by the present invention are: How to intelligently determine whether a ship should switch fuel and ensure the pass rate of the ship's fuel switch.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions: A method for intelligent switching control of LNG-methanol dual fuel for ships, the method comprising: Step S1, acquiring real-time navigation data of the ship, and obtaining the signal type of the fuel switching signal of the ship according to the real-time navigation data; Step S2: Analyze the external environment of the ship based on the real-time navigation data of the ship, and determine whether the ship meets the pipeline purge conditions based on the external environment; Step S3, obtaining methanol usage data, liquefied natural gas usage data, and pipeline usage data of the ship, and simultaneously controlling the inert gas to purge the main input pipeline in the ship, and obtaining a pipeline purge completion instruction; Step S4: acquiring the real-time operating data of the ship, and determining whether the fuel switching control of the ship is qualified based on the real-time operating data.

[0006] Furthermore, the real-time navigation data includes the real-time travel coordinates of the ship, the real-time speed of the ship and the real-time heading of the ship.

[0007] Furthermore, the step S1 includes the following sub-steps: Step S11, obtaining the port coordinates of the target port, constructing a circular area with the port coordinates as the center and the fixed port distance as the radius, dividing the circular area into a land area and a navigation area according to the coastline, and using the navigation area as the port management area of ​​the target port; Step S12: obtaining the real-time coordinates of the ship. When the real-time coordinates intersect with the edge of the port management area, obtaining the real-time speed of the ship and the corresponding time node; Step S13: The time node when the ship intersects the edge of the port management area is used as the reference time node, and then the real-time speed of the ship is bound to the timestamp to obtain the real-time speed of the ship at all time nodes, and the acceleration of the ship at the current time node is calculated; Step S14: When the acceleration of the ship is less than zero and the real-time heading of the ship is entering the port management area, it is determined that the ship needs to enter the port management area, the state of the ship is decelerated, and the current fuel consumption of the ship is detected; If the ship's current fuel is liquefied natural gas, the fuel switching signal sent by the ship is a methanol switching signal; If the ship is currently using methanol as fuel, no operation will be performed; Step S15: When the acceleration of the ship is less than zero and the real-time heading of the ship is to leave the port management area, it is determined that the ship needs to leave the port management area, the state of the ship is decelerated, and the current fuel consumption of the ship is detected; If the ship is currently using methanol as fuel, the fuel switching signal sent by the ship will be a signal type of switching to liquefied natural gas; If the ship is currently using liquefied natural gas as fuel, no action will be taken; Step S16: When the acceleration of the ship is greater than or equal to zero, it is determined that the ship needs to leave the port management area, the ship is in an accelerating state, and the current fuel consumption of the ship is detected; If the ship is currently using liquefied natural gas as fuel, no action will be taken; If the fuel currently used by the ship is methanol, the signal type of the fuel switching signal sent by the ship is a switching liquefied natural gas signal.

[0008] Furthermore, step S2 includes the following sub-steps: Step S21, obtaining the real-time heading of the ship, binding the real-time heading of the ship to the timestamp, and then constructing a heading-time node curve; Step S22: If the signal type is a methanol switching signal, analyze the heading-time node curve; When the slope of any point in the heading-time node curve is greater than or equal to the slope threshold within a fixed number of time nodes, it is determined that the ship is performing a turning operation and the ship does not meet the pipeline purge conditions; When the slopes corresponding to all time nodes in the heading-time node curve are less than the slope threshold within a fixed number of time nodes, the ship is judged to meet the pipeline purge conditions and a start purge instruction is issued; Step S23: If the signal type is a liquefied natural gas switching signal, the heading-time node curve is analyzed; When the slope of any point in the heading-time node curve is greater than or equal to the slope threshold within a fixed number of time nodes, the pipeline purge condition is not met; When the slopes corresponding to all time nodes in the heading-time node curve are less than the slope threshold within a fixed number of time nodes, step S24 is entered; Step S24, obtaining the real-time speed of the ship. If the real-time speed of the ship is greater than or equal to the speed threshold, it is determined that the ship does not meet the pipeline purge conditions; If the real-time speed of the ship is less than the speed threshold, it is determined that the ship meets the pipeline purge conditions and a start purge instruction is issued.

[0009] Furthermore, the methanol usage data includes the methanol preheating interval and the storage volume of the methanol storage tank; LNG usage data includes the LNG preheating interval and the storage volume of the LNG storage tank; The pipeline usage data includes the real-time fuel concentration, methanol input rate and liquefied natural gas input rate of the main input pipeline in the ship.

[0010] Furthermore, purging the main input pipeline in the ship is to discharge the methanol or liquefied natural gas in the main input pipeline by supplying inert gas to the main input pipeline, thereby achieving the purpose of reducing the concentration of methanol or liquefied natural gas; The real-time concentrations of fuels in the main input pipeline are: real-time concentration of liquefied natural gas and real-time concentration of methanol.

[0011] Furthermore, step S3 includes the following sub-steps: Step S31, when the ship issues a start purge instruction, the signal type of the fuel switching signal is obtained. When the fuel switching signal is a methanol switching signal, the process proceeds to step S32; When the fuel switching signal is a liquefied natural gas switching signal, the process proceeds to step S37; Step S32, obtaining a preheating interval of methanol, heating the methanol input pipeline to a maximum endpoint value corresponding to the preheating interval of methanol, and then inputting methanol from the methanol low-temperature storage device into the methanol input pipeline; Step S33: fixing the storage tank temperature of the methanol storage tank to the standard methanol preheating temperature, obtaining the storage volume of the methanol storage tank and the methanol input rate of the main input pipeline in the ship, and dividing the storage volume by the methanol input rate to obtain the filling time required to fill the methanol storage tank; In step S34, the corresponding pipeline valve of the liquefied natural gas input pipeline is closed, and the corresponding time node when methanol is transported from the methanol low-temperature storage device to the methanol storage tank through the methanol input pipeline is used as the initial time node. The real-time concentration of liquefied natural gas in the main input pipeline at the initial time node is obtained and recorded as the initial liquefied natural gas concentration QCN.

[0012] Furthermore, the step S3 further includes the following sub-steps: Step S35: When purging the main input pipeline, obtain the standard net inert gas discharge volume for the intelligent manufacturing equipment industry and the pipeline volume of the main input pipeline, then increment the initial time node by the filling time to calculate the final liquefied natural gas concentration at the corresponding time node; Step S36: If the final LNG concentration is greater than or equal to the LNG concentration threshold, it is determined that the net inert gas discharge does not meet the standard, and the net inert gas discharge is automatically controlled to increase until the final LNG concentration is less than the LNG concentration threshold; If the final LNG concentration is less than the LNG concentration threshold, the ship issues a pipeline purge completion command; Step S37: Obtain the LNG preheating interval, storage temperature, and storage volume of the LNG storage tank. Calculate the filling time of the LNG storage tank using the same steps as those for calculating the filling time of the methanol storage tank. Similarly, calculate the filling time of the LNG storage tank. Step S38, the corresponding step of reducing the methanol concentration in the main input pipeline is the same as the corresponding step of reducing the liquefied natural gas concentration in the main input pipeline. Similarly, the pipeline valve corresponding to the methanol input pipeline is closed, and the pipeline is purged with inert gas to make the final methanol concentration in the main input pipeline less than the methanol concentration threshold. At the same time, the ship issues a pipeline purge completion instruction.

[0013] Furthermore, the real-time working data specifically includes the real-time pipeline pressure and the real-time injection flow of the main input pipeline in the ship, and the real-time combustion temperature of the engine.

[0014] Furthermore, step S4 includes the following sub-steps: Step S41: When the ship issues a pipeline purge completion instruction, the control device opens the corresponding pipeline valve of the input pipeline and inputs fuel to the engine; Step S42: Acquire the real-time injection flow rate of the main input pipeline. If the real-time pipeline pressure of the main input pipeline does not fall within the pipeline pressure range, or the real-time injection flow rate is greater than the injection flow rate threshold, it is determined that the fuel switching control of the ship has failed, and the control device closes the corresponding pipeline valve of the input pipeline; If the real-time pipeline pressure of the main input pipeline belongs to the pipeline pressure range and the real-time injection flow rate is less than or equal to the injection flow rate threshold, proceed to the next step; Step S43, obtaining the real-time combustion temperature in the engine. If the real-time combustion temperature falls within the methanol combustion temperature range, it is determined that the fuel switching control of the ship is qualified. When the real-time combustion temperature does not fall within the methanol combustion temperature range, the fuel switching control of the ship is determined to be unqualified.

[0015] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are: 1. The present invention obtains the signal type of the ship's fuel switching signal based on real-time navigation data, and then analyzes the real-time navigation data to obtain the ship's external environment. Based on the external environment, it determines whether the ship meets the pipeline purge conditions. The present invention determines whether the ship meets the fuel switching conditions through environmental analysis; 2. The present invention controls the purge of inert gas into the main input pipeline of the ship based on the methanol usage data, liquefied natural gas usage data and pipeline usage data of the ship's fuel, and finally determines whether the ship's fuel switching control is qualified based on real-time working data. The present invention also cleans the ship's fuel pipeline during the fuel switching process to ensure the qualified rate of the ship's fuel switching. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] To facilitate understanding by those skilled in the art, the present invention is further described below with reference to the accompanying drawings.

[0017] Figure 1 is a flow chart of the method of the present invention; Figure 2 This is an example diagram of the port management area in the present invention; Figure 3 This is an example diagram of the real-time heading of a ship in the present invention; Figure 4 is an example diagram of a storage device in the present invention; Figure 5 It is a structural schematic diagram of the electronic device in the present invention. DETAILED DESCRIPTION

[0018] The technical solutions of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0019] Example 1: Please refer to Figures 1-4 As shown, the technical solution provided by the present invention is: a ship LNG methanol dual fuel intelligent switching control method, the method is as follows: Step S1, acquiring real-time navigation data of the ship, and obtaining the signal type of the fuel switching signal of the ship according to the real-time navigation data; Among them, the real-time navigation data specifically includes the real-time coordinates of the ship, the real-time speed of the ship and the real-time heading of the ship; Specifically, the fuel switching signal is a signal for the ship to switch fuel when the ship reaches a designated position and performs a designated operation; It should be noted that the signal types are specifically switching methanol signals and switching liquefied natural gas signals; In this embodiment, step S1 includes the following sub-steps: Step S11, as Figure 2 As shown, the port coordinates of the target port are obtained, and a circular area is constructed with the port coordinates as the center and the fixed port distance as the radius. The circular area is divided into a land area and a navigation area according to the coastline, and the navigation area is used as the port management area of ​​the target port; Step S12: obtaining the real-time coordinates of the ship. When the real-time coordinates intersect with the edge of the port management area, obtaining the real-time speed of the ship and the corresponding time node; In step S13, the time node when the ship intersects the edge of the port management area is used as the reference time node, and then the real-time speed of the ship is bound to the timestamp to obtain the real-time speed of the ship at all time nodes SSHi, where i is the time node number, i=1, 2, ..., n, and n is a positive integer. The acceleration a of the ship at the current time node is calculated by the formula, which is as follows: a=(SSHi-SSHi-1) / [i-(i-1)]; Among them, when the acceleration of the ship is less than zero, it is determined that the ship is decelerating; when the acceleration of the ship is greater than zero, it is determined that the ship is accelerating; when the acceleration of the ship is equal to zero, it is determined that the ship is traveling at a constant speed; In practice, the time difference between adjacent time nodes is one second; Step S14: When the acceleration of the ship is less than zero and the real-time heading of the ship is entering the port management area, it is determined that the ship needs to enter the port management area, the state of the ship is decelerated, and the current fuel consumption of the ship is detected; If the ship's current fuel is liquefied natural gas, the fuel switching signal sent by the ship is a methanol switching signal; If the ship is currently using methanol as fuel, no operation will be performed; Step S15: When the acceleration of the ship is less than zero and the real-time heading of the ship is to leave the port management area, it is determined that the ship needs to leave the port management area, the state of the ship is decelerated, and the current fuel consumption of the ship is detected; If the ship is currently using methanol as fuel, the fuel switching signal sent by the ship will be a signal type of switching to liquefied natural gas; If the ship is currently using liquefied natural gas as fuel, no action will be taken; It should be specifically noted that when the ship's acceleration is less than zero and the ship's real-time heading is to leave the port management area, the ship needs to avoid other ships within the ship's real-time heading, so it needs to slow down, causing the ship's acceleration to be less than zero; Step S16: When the acceleration of the ship is greater than or equal to zero, it is determined that the ship needs to leave the port management area, the ship is in an accelerating state, and the current fuel consumption of the ship is detected; If the ship is currently using liquefied natural gas as fuel, no action will be taken; If the ship is currently using methanol as fuel, the fuel switching signal sent by the ship will be a liquefied natural gas switching signal; The fuels used by ships are liquefied natural gas (LNG) and methanol. Given the same volume and combustion duration, the heat generated by LNG combustion is higher than that generated by methanol combustion. Therefore, the power generated by LNG combustion is higher than that generated by methanol combustion. It should be specifically noted that when a ship enters a port management area, it must slow down and make fine adjustments to its own speed and direction, so methanol is needed as fuel; when a ship leaves a port management area, it needs to accelerate quickly or leave at a constant speed, so liquefied natural gas is needed as fuel.

[0020] Step S2: Analyze the external environment of the ship based on the real-time navigation data of the ship, and determine whether the ship meets the pipeline purge conditions based on the external environment; In this embodiment, step S2 includes the following sub-steps: Step S21, obtaining the real-time heading of the ship, binding the real-time heading of the ship to the timestamp, and then constructing a heading-time node curve; Step S22: If the signal type is a methanol switching signal, analyze the heading-time node curve; When the slope of any point in the heading-time node curve is greater than or equal to the slope threshold within a fixed number of time nodes, it is determined that the ship is performing a turning operation and the ship does not meet the pipeline purge conditions; When the slopes corresponding to all time nodes in the heading-time node curve are less than the slope threshold within a fixed number of time nodes, the ship is judged to meet the pipeline purge conditions and a start purge instruction is issued; Step S23: If the signal type is a liquefied natural gas switching signal, the heading-time node curve is analyzed; When the slope of any point in the heading-time node curve is greater than or equal to the slope threshold within a fixed number of time nodes, it is determined that the ship is performing a turning operation and the pipeline purge condition is not met; When the slopes corresponding to all time nodes in the heading-time node curve are less than the slope threshold within a fixed number of time nodes, step S24 is entered; Step S24, obtaining the real-time speed of the ship. If the real-time speed of the ship is greater than or equal to the speed threshold, it is determined that the ship does not meet the pipeline purge conditions; If the real-time speed of the ship is less than the speed threshold, it is determined that the ship meets the pipeline purge conditions and a start purge instruction is issued.

[0021] Step S3, obtaining methanol usage data, liquefied natural gas usage data, and pipeline usage data of the ship, and simultaneously controlling the inert gas to purge the main input pipeline in the ship, and obtaining a pipeline purge completion instruction; The methanol usage data specifically includes the methanol preheating interval and the storage volume of the methanol storage tank; the liquefied natural gas usage data specifically includes the liquefied natural gas preheating interval and the storage volume of the liquefied natural gas storage tank; the pipeline usage data specifically includes the real-time fuel concentration, methanol input rate, and liquefied natural gas input rate of the main input pipeline within the ship; Specifically, the main input pipeline in the ship is purged by: discharging methanol or liquefied natural gas in the main input pipeline by supplying inert gas to the main input pipeline, thereby achieving the purpose of reducing the concentration of methanol or liquefied natural gas; In practice, the preheating range of methanol is specifically [40°C to 60°C]; the real-time concentration of fuel in the main input pipeline is specifically the real-time concentration of liquefied natural gas and the real-time concentration of methanol; In this embodiment, step S3 includes the following sub-steps: Step S31, when the ship issues a start purge instruction, the signal type of the fuel switching signal is obtained. When the fuel switching signal is a methanol switching signal, the process proceeds to step S32; When the fuel switching signal is a liquefied natural gas switching signal, the process proceeds to step S37; Step S32, as Figure 4 As shown, the preheating interval of methanol is obtained, the methanol input pipeline is heated to the maximum endpoint value corresponding to the preheating interval of methanol, and then methanol is input from the methanol low-temperature storage device to the methanol input pipeline; In a specific implementation, in a methanol low-temperature storage device, the storage temperature of methanol is 20°C, and the maximum endpoint value of the methanol preheating range is 60°C. Since the storage temperature of methanol is relatively low and the boiling temperature of methanol is 65°C, methanol at the storage temperature can be input into the methanol input pipeline to prevent the methanol from boiling due to the excessively high preheating temperature. Step S33: fixing the storage tank temperature of the methanol storage tank to the standard methanol preheating temperature, obtaining the storage volume of the methanol storage tank and the methanol input rate of the main input pipeline in the ship, and dividing the storage volume by the methanol input rate to obtain the filling time required to fill the methanol storage tank; The unit of methanol input rate is cubic meters per minute; In specific implementation, the standard methanol preheating temperature may be 50°C; Step S34: Close the corresponding pipeline valve of the liquefied natural gas input pipeline, use the time point corresponding to the time when methanol is transported from the methanol low-temperature storage device to the methanol storage tank through the methanol input pipeline as the initial time point, obtain the real-time liquefied natural gas concentration of the main input pipeline at the initial time point, and record it as the liquefied natural gas initial concentration QCN; In step S35, when the main input pipeline is purged, the standard inert gas net displacement DPL for the intelligent manufacturing equipment industry and the pipeline volume GDT of the main input pipeline are obtained. Then, the initial time node is increased by the filling time CSC, and the final concentration ZND of the liquefied natural gas at the corresponding time node is calculated using the formula. The specific formula is as follows: ; The inert gas may be nitrogen, argon, helium or neon. In this embodiment, nitrogen is preferably used as the inert gas. Compared with other inert gases, nitrogen has lower cost and is easier to obtain. Specifically, the inert gas is stored in an inert gas storage tank, which is directly connected to the main input pipeline; the inert gas storage tank is connected to a control device, which is used to change the net discharge volume of the inert gas; Step S36: If the final LNG concentration is greater than or equal to the LNG concentration threshold, it is determined that the net inert gas discharge does not meet the standard, and the net inert gas discharge is automatically controlled to increase until the final LNG concentration is less than the LNG concentration threshold; If the final LNG concentration is less than the LNG concentration threshold, the ship issues a pipeline purge completion command; Specifically, the liquefied natural gas concentration threshold is a concentration value at which, when liquefied natural gas and methanol are mixed, the liquefied natural gas has no effect on the combustion of methanol; Step S37: Obtain the LNG preheating interval, storage temperature, and storage volume of the LNG storage tank. Calculate the filling time of the LNG storage tank using the same steps as those for calculating the filling time of the methanol storage tank. Similarly, calculate the filling time of the LNG storage tank. Step S38, the corresponding step of reducing the methanol concentration in the main input pipeline is the same as the corresponding step of reducing the liquefied natural gas concentration in the main input pipeline. Similarly, the pipeline valve corresponding to the methanol input pipeline is closed, and the pipeline is purged with inert gas to make the final methanol concentration in the main input pipeline less than the methanol concentration threshold. At the same time, the ship issues a pipeline purge completion instruction.

[0022] Step S4, acquiring real-time operating data of the ship, and determining whether the fuel switching control of the ship is qualified based on the real-time operating data; The real-time working data specifically includes the real-time pipeline pressure and injection flow of the main input pipeline in the ship, and the real-time combustion temperature of the engine; It should be specifically noted that step S4 only analyzes the combustion status of methanol, and the analysis of liquefied natural gas is similar; In this embodiment, step S4 includes the following sub-steps: Step S41: When the ship issues a pipeline purge completion instruction, the control device opens the corresponding pipeline valve of the input pipeline and inputs fuel to the engine; Step S42: Acquire the real-time injection flow rate of the main input pipeline. If the real-time pipeline pressure of the main input pipeline does not fall within the pipeline pressure range, or the real-time injection flow rate is greater than the injection flow rate threshold, it is determined that the fuel switching control of the ship has failed, and the control device closes the corresponding pipeline valve of the input pipeline; If the real-time pipeline pressure of the main input pipeline belongs to the pipeline pressure range and the real-time injection flow rate is less than or equal to the injection flow rate threshold, proceed to the next step; Step S43, obtaining the real-time combustion temperature in the engine. If the real-time combustion temperature falls within the methanol combustion temperature range, it is determined that the fuel switching control of the ship is qualified. When the real-time combustion temperature does not fall within the methanol combustion temperature range, the fuel switching control of the ship is judged to be unqualified; It should be noted that the methanol combustion temperature range is [1427°C ~ 1627°C], and the liquefied natural gas combustion temperature range is [1627°C ~ 1827°C]. Therefore, if the real-time combustion temperature does not fall within the methanol combustion temperature range, the final concentration of the liquefied natural gas in the main input pipeline is judged to be unqualified, and the fuel switching control of the ship is also judged to be unqualified.

[0023] In this application, if a corresponding calculation formula appears, the above calculation formula is dimensionless and its numerical calculation is performed. The weight coefficient, proportional coefficient and other coefficients in the formula are set to a result value obtained by quantifying each parameter. Regarding the size of the weight coefficient and the proportional coefficient, as long as it does not affect the proportional relationship between the parameter and the result value, it is acceptable.

[0024] Example 2: The present invention also provides a computer device for running the above-mentioned ship LNG methanol dual fuel intelligent switching control method; see Figure 5 The structure diagram of a computer device provided by an embodiment of the present invention is shown, wherein the computer device includes a memory and a processor, wherein the memory is used to store one or more computer instructions, and the one or more computer instructions are executed by the processor to implement the above-mentioned ship LNG methanol dual-fuel intelligent switching control method; Further, Figure 5 The computer device shown further includes a communication bus and a communication interface, and the processor, the communication interface and the memory are connected via the communication bus; The memory may include high-speed random access memory (RAM) and may also include non-volatile memory, such as at least one disk storage. The communication connection between the system network element and at least one other network element is achieved through at least one communication interface (which can be wired or wireless), and the Internet, wide area network, local area network, metropolitan area network, etc. can be used. The communication bus can be an ISA bus, PCI bus or EISA bus, etc. The communication bus can be divided into an address bus, a data bus, a control bus, etc. For ease of representation, Figure 5 Only one bidirectional arrow is used, but it does not mean that there is only one communication bus or one type of communication bus; The processor may be an integrated circuit chip with signal processing capabilities. During implementation, each step of the above method may be completed by hardware integrated logic circuits in the processor or by software instructions. The above processor may be a general-purpose processor, including a central processing unit (CPU), a network processor (NP), etc.; it may also be a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components. The methods, steps, and logic block diagrams disclosed in the embodiments of the present invention may be implemented or executed. The general-purpose processor may be a microprocessor or any conventional processor. The steps of the method disclosed in conjunction with the embodiments of the present invention may be directly implemented and executed by a hardware decoding processor, or by a combination of hardware and software modules in the decoding processor. The software module may be located in a storage medium well-known in the art, such as random access memory, flash memory, read-only memory, programmable read-only memory, electrically erasable programmable memory, registers, or the like. The storage medium is located in the memory, and the processor reads the information in the memory and completes the steps of the method of the above embodiment in combination with its hardware.

[0025] Example 3. The embodiment of the present invention further provides a computer storage medium, which stores computer executable instructions. When the computer executable instructions are called and executed by the processor, the computer executable instructions prompt the processor to implement the above-mentioned ship LNG methanol dual-fuel intelligent switching control method. For specific implementation, please refer to the method embodiment. The method is: obtaining real-time navigation data of the ship, and obtaining the signal type of the ship's fuel switching signal based on the real-time navigation data; analyzing the external environment of the ship based on the real-time navigation data of the ship, and determining whether the ship meets the pipeline purge conditions based on the external environment; obtaining methanol usage data, liquefied natural gas usage data and pipeline usage data of the ship's fuel, and at the same time controlling the inert gas to purge the main input pipeline in the ship, and obtaining a pipeline purge completion instruction; obtaining real-time working data of the ship, and determining whether the fuel switching control of the ship is qualified based on the real-time working data; A computer program product of a ship LNG methanol dual-fuel intelligent switching control method provided by an embodiment of the present invention includes a computer storage medium storing program code. The instructions included in the program code can be used to execute the method in the previous method embodiment. For specific implementation, please refer to the method embodiment. The method is: obtaining real-time navigation data of the ship, and obtaining the signal type of the ship's fuel switching signal based on the real-time navigation data; analyzing the external environment of the ship based on the real-time navigation data of the ship, and determining whether the ship meets the pipeline purge conditions based on the external environment; obtaining methanol usage data, liquefied natural gas usage data and pipeline usage data of the ship's fuel, and at the same time controlling the inert gas to purge the main input pipeline in the ship, and obtaining a pipeline purge completion instruction by the purge; obtaining real-time working data of the ship, and determining whether the ship's fuel switching control is qualified based on the real-time working data.

[0026] Those skilled in the art will clearly understand that, for the convenience and brevity of description, the specific working process of the system and / or device described above can refer to the corresponding process in the aforementioned method embodiment and will not be repeated here.

[0027] In addition, in the description of the embodiments of the present invention, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integral connections; they may refer to mechanical connections or electrical connections; they may refer to direct connections or indirect connections through an intermediate medium; and they may refer to internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on the specific circumstances.

[0028] If the functions are implemented as software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the portion that contributes to the prior art, or a portion of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for causing a computer device (which can be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in various embodiments of the present invention. The aforementioned storage media include various media capable of storing program code, such as USB flash drives, mobile hard drives, read-only memories (ROMs), random access memories (RAMs), magnetic disks, or optical disks.

[0029] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the above embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A ship LNG methanol dual fuel intelligent switching control method, characterized in that: Methods include: Step S1, acquiring real-time navigation data of the ship, and obtaining the signal type of the fuel switching signal of the ship according to the real-time navigation data; Step S2: Analyze the external environment of the ship based on the real-time navigation data of the ship, and determine whether the ship meets the pipeline purge conditions based on the external environment; Step S3, obtaining methanol usage data, liquefied natural gas usage data, and pipeline usage data of the ship, and simultaneously controlling the inert gas to purge the main input pipeline in the ship, and obtaining a pipeline purge completion instruction; Step S4: acquiring the real-time operating data of the ship, and determining whether the fuel switching control of the ship is qualified based on the real-time operating data.

2. The method for intelligent switching control of LNG-methanol dual fuel for ships according to claim 1, characterized in that: The real-time navigation data includes the real-time coordinates of the ship, the real-time speed of the ship and the real-time heading of the ship.

3. The method for intelligent switching control of LNG-methanol dual fuel for ships according to claim 2, characterized in that: The step S1 includes the following sub-steps: Step S11, obtaining the port coordinates of the target port, constructing a circular area with the port coordinates as the center and the fixed port distance as the radius, dividing the circular area into a land area and a navigation area according to the coastline, and using the navigation area as the port management area of ​​the target port; Step S12: obtaining the real-time coordinates of the ship. When the real-time coordinates intersect with the edge of the port management area, obtaining the real-time speed of the ship and the corresponding time node; Step S13: The time node when the ship intersects the edge of the port management area is used as the reference time node, and then the real-time speed of the ship is bound to the timestamp to obtain the real-time speed of the ship at all time nodes, and the acceleration of the ship at the current time node is calculated; Step S14: When the acceleration of the ship is less than zero and the real-time heading of the ship is entering the port management area, it is determined that the ship needs to enter the port management area, the state of the ship is decelerated, and the current fuel consumption of the ship is detected; If the ship's current fuel is liquefied natural gas, the fuel switching signal sent by the ship is a methanol switching signal; If the ship is currently using methanol as fuel, no operation will be performed; Step S15: When the acceleration of the ship is less than zero and the real-time heading of the ship is to leave the port management area, it is determined that the ship needs to leave the port management area, the state of the ship is decelerated, and the current fuel consumption of the ship is detected; If the ship is currently using methanol as fuel, the fuel switching signal sent by the ship will be a signal type of switching to liquefied natural gas; If the ship is currently using liquefied natural gas as fuel, no action will be taken; Step S16: When the acceleration of the ship is greater than or equal to zero, it is determined that the ship needs to leave the port management area, the ship is in an accelerating state, and the current fuel consumption of the ship is detected; If the ship is currently using liquefied natural gas as fuel, no action will be taken; If the fuel currently used by the ship is methanol, the signal type of the fuel switching signal sent by the ship is a switching liquefied natural gas signal.

4. The method for intelligent switching control of LNG-methanol dual fuel for ships according to claim 1, characterized in that: The step S2 includes the following sub-steps: Step S21, obtaining the real-time heading of the ship, binding the real-time heading of the ship to the timestamp, and then constructing a heading-time node curve; Step S22: If the signal type is a methanol switching signal, analyze the heading-time node curve; When the slope of any point in the heading-time node curve is greater than or equal to the slope threshold within a fixed number of time nodes, the ship does not meet the pipeline purge conditions; When the slopes corresponding to all time nodes in the heading-time node curve are less than the slope threshold within a fixed number of time nodes, the ship meets the pipeline purge conditions and issues a start purge command; Step S23: If the signal type is a liquefied natural gas switching signal, the heading-time node curve is analyzed; When the slope of any point in the heading-time node curve is greater than or equal to the slope threshold within a fixed number of time nodes, the pipeline purge condition is not met; When the slopes corresponding to all time nodes in the heading-time node curve are less than the slope threshold within a fixed number of time nodes, step S24 is entered; Step S24, obtaining the real-time speed of the ship. If the real-time speed of the ship is greater than or equal to the speed threshold, it is determined that the ship does not meet the pipeline purge conditions; If the real-time speed of the ship is less than the speed threshold, it is determined that the ship meets the pipeline purge conditions and a start purge instruction is issued.

5. The method for intelligent switching control of LNG-methanol dual fuel for ships according to claim 4, characterized in that: Methanol usage data includes the methanol preheating interval and the storage volume of the methanol storage tank; LNG usage data includes the LNG preheating interval and the storage volume of the LNG storage tank; The pipeline usage data includes the real-time fuel concentration, methanol input rate and liquefied natural gas input rate of the main input pipeline in the ship.

6. The method for intelligent switching control of LNG-methanol dual fuel for ships according to claim 5, characterized in that: Purging the main inlet pipe in a ship involves discharging methanol or liquefied natural gas in the main inlet pipe by delivering inert gas to the main inlet pipe, thereby reducing the concentration of methanol or liquefied natural gas. The real-time concentrations of fuels in the main input pipeline are: real-time concentration of liquefied natural gas and real-time concentration of methanol.

7. The method for intelligent switching control of LNG-methanol dual fuel for ships according to claim 5, characterized in that: The step S3 includes the following sub-steps: Step S31, when the ship issues a start purge instruction, the signal type of the fuel switching signal is obtained. When the fuel switching signal is a methanol switching signal, the process proceeds to step S32; When the fuel switching signal is a liquefied natural gas switching signal, the process proceeds to step S37; Step S32, obtaining a preheating interval of methanol, heating the methanol input pipeline to a maximum endpoint value corresponding to the preheating interval of methanol, and then inputting methanol from the methanol low-temperature storage device into the methanol input pipeline; Step S33: fixing the storage tank temperature of the methanol storage tank to the standard methanol preheating temperature, obtaining the storage volume of the methanol storage tank and the methanol input rate of the main input pipeline in the ship, and dividing the storage volume by the methanol input rate to obtain the filling time required to fill the methanol storage tank; In step S34, the corresponding pipeline valve of the liquefied natural gas input pipeline is closed, and the corresponding time node when methanol is transported from the methanol low-temperature storage device to the methanol storage tank through the methanol input pipeline is used as the initial time node. The real-time concentration of liquefied natural gas in the main input pipeline at the initial time node is obtained and recorded as the initial liquefied natural gas concentration QCN.

8. The method for intelligent switching control of LNG-methanol dual fuel for ships according to claim 7, characterized in that: The step S3 further includes the following sub-steps: Step S35: When purging the main input pipeline, obtain the standard net inert gas discharge volume for the intelligent manufacturing equipment industry and the pipeline volume of the main input pipeline, then increment the initial time node by the filling time to calculate the final liquefied natural gas concentration at the corresponding time node; Step S36: If the final LNG concentration is greater than or equal to the LNG concentration threshold, it is determined that the net inert gas discharge does not meet the standard, and the net inert gas discharge is automatically controlled to increase until the final LNG concentration is less than the LNG concentration threshold; If the final LNG concentration is less than the LNG concentration threshold, the ship issues a pipeline purge completion command; Step S37: Obtain the LNG preheating interval, storage temperature, and storage volume of the LNG storage tank. Calculate the filling time of the LNG storage tank using the same steps as those for calculating the filling time of the methanol storage tank. Similarly, calculate the filling time of the LNG storage tank. Step S38, the corresponding step of reducing the methanol concentration in the main input pipeline is the same as the corresponding step of reducing the liquefied natural gas concentration in the main input pipeline. Similarly, the pipeline valve corresponding to the methanol input pipeline is closed, and the pipeline is purged with inert gas to make the final methanol concentration in the main input pipeline less than the methanol concentration threshold. At the same time, the ship issues a pipeline purge completion instruction.

9. The method for intelligent switching control of LNG-methanol dual fuel for ships according to claim 8, characterized in that: The real-time working data specifically includes the real-time pipeline pressure of the main input pipeline in the ship, the real-time injection flow, and the real-time combustion temperature of the engine.

10. The method for intelligent switching control of LNG-methanol dual fuel for ships according to claim 9, characterized in that: The step S4 includes the following sub-steps: Step S41: When the ship issues a pipeline purge completion instruction, the control device opens the corresponding pipeline valve of the input pipeline and inputs fuel to the engine; Step S42: Acquire the real-time injection flow rate of the main input pipeline. If the real-time pipeline pressure of the main input pipeline does not fall within the pipeline pressure range, or the real-time injection flow rate is greater than the injection flow rate threshold, it is determined that the fuel switching control of the ship has failed, and the control device closes the corresponding pipeline valve of the input pipeline; If the real-time pipeline pressure of the main input pipeline belongs to the pipeline pressure range and the real-time injection flow rate is less than or equal to the injection flow rate threshold, proceed to the next step; Step S43, obtaining the real-time combustion temperature in the engine. If the real-time combustion temperature falls within the methanol combustion temperature range, it is determined that the fuel switching control of the ship is qualified. When the real-time combustion temperature does not fall within the methanol combustion temperature range, the fuel switching control of the ship is determined to be unqualified.

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