Pure methanol hot surface compression ignition engine glow plug arrangement, method and system

Abstract

The present application relates to pure methanol hot surface compression ignition engine glow plug arrangement structure, method and system. The present application includes ECU control unit, glow plug control unit, cylinder, cylinder head base, methanol injector; multiple valve seats; single or multiple glow plugs, installed on the cylinder head base and located in the area between the valve seat and the methanol injector, and symmetrically distributed around the methanol injector, the heating part of each glow plug extends into the combustion chamber; the ECU control unit can send control signals to the glow plug control unit according to the sensor signals; the glow plug control unit can determine the number of glow plugs turned on for heating in each cycle according to the sum of the methanol temperature and the intake air temperature, and determine the time of the glow plug turned on for heating according to the engine speed. The present application solves the problems of existing large bore methanol engine, such as difficult cold start and unstable combustion.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of engines, in particular to a pure methanol hot surface compression ignition engine glow plug arrangement structure, method and system. BACKGROUND

[0002] Large-bore methanol compression ignition engines have attracted much attention in the fields of shipbuilding, power generation and heavy transportation due to their unique advantages. From the perspective of energy characteristics, methanol is a clean low-carbon fuel with a high oxygen content of 50%, which creates favorable conditions for its complete combustion, theoretically significantly reducing harmful gas emissions and reducing environmental pollution. At the same time, methanol is widely available, whether it is made from coal, natural gas or biomass, which greatly alleviates the pressure of the increasingly depleted traditional fossil energy and provides a reliable guarantee for energy diversification. In practical application scenarios, large-bore methanol compression ignition engines exhibit good economy and environmental protection, and compared with traditional fuel engines, they can effectively reduce fuel costs and improve economic efficiency under most operating conditions.

[0003] However, large-bore methanol compression ignition engines still face many technical bottlenecks. The self-ignition temperature of methanol is as high as 723K, much higher than that of diesel fuel at 523K, which makes it difficult to achieve the conditions required for methanol self-ignition during normal compression in the engine. Additional auxiliary ignition measures are needed. Its high latent heat of vaporization (1100kJ / kg) will absorb a large amount of heat during vaporization, especially in low temperature environments, which will cause a sharp drop in cylinder temperature and make it difficult for the mixture to reach the self-ignition critical point, making cold start extremely difficult. The large-bore engine combustion chamber has a large space, and the uniformity of methanol and air mixing is difficult to guarantee, the flame propagation distance is long, and problems such as incomplete combustion and unstable combustion speed are prone to occur, which seriously affect the power output and thermal efficiency of the engine.

[0004] In addition, existing glow plug technology cannot meet the needs of large-bore methanol engines. Single-point glow plug technology has obvious defects in large-bore engines, as it cannot effectively cover the range of large-bore engines, which can easily cause local overheating or insufficient heating. This not only leads to unstable ignition, but also can cause abnormal combustion or misfire. Even though some technologies use multiple glow plugs, there are still problems with the layout, such as asymmetry and unreasonable parameter settings, which can cause spray blockage and the formation of local rich zones, with a combustion fluctuation rate of more than 15%, seriously affecting combustion stability and making it difficult to achieve efficient and stable combustion. Therefore, using a multiple-point symmetrical arrangement of glow plugs and optimizing the layout of the glow plugs is one of the key directions to solve these problems.

[0005] In addition to the glow plug layout problem, the glow plug temperature control is also the core point to realize stable compression ignition. The current technology cannot adjust the temperature of the glow plug in real time according to the engine working condition. When the engine is running, the methanol injection amount, intake air amount, intake air temperature, coolant temperature and other parameters change constantly, and the existing glow plug temperature control often lags behind or does not match. When starting at low temperature, if the glow plug heating is insufficient, the methanol cannot be fully evaporated, which will cause misfire; under high temperature or high load working condition, abnormal combustion may occur due to local high temperature, increasing the risk of knock. Long-term accumulation will cause fatigue damage of key components such as piston and connecting rod, shorten the service life of the engine and increase the maintenance cost.

[0006] In summary, in order to break through the practical bottleneck of large-bore methanol engine, a compression ignition control method capable of coupling multi-dimensional working condition parameters in real time and dynamically optimizing the temperature field of the glow plug is needed. From the aspects of layout optimization and accurate temperature control, the current technical problems are solved. SUMMARY

[0007] Therefore, the technical problem to be solved by the present application is to overcome the cold start difficulty and unstable combustion of the large-bore methanol engine in the actual application in the prior art.

[0008] To solve the above technical problems, the present application provides a pure methanol hot surface compression ignition engine glow plug arrangement structure, comprising:

[0009] An ECU control unit is used to receive sensor signals from the methanol compression ignition engine, and the sensor signals include coolant temperature signal, methanol temperature signal, intake air temperature signal and speed signal;

[0010] A glow plug control unit is connected with the ECU control unit;

[0011] A cylinder is provided with a combustion chamber for mixing and burning methanol and air;

[0012] A cylinder head base is arranged on the cylinder;

[0013] A methanol injector is installed at the center of the cylinder head base and extends into the combustion chamber to inject methanol fuel into the combustion chamber;

[0014] A plurality of valve seats are installed on the cylinder head base and can communicate with the combustion chamber, and the plurality of valve seats are centrally symmetrically distributed around the methanol injector;

[0015] One or more glow plugs are installed on the cylinder head base and located in the area between the valve seat and the methanol injector, and the heating part of each glow plug extends into the combustion chamber;

[0016] The ECU control unit is capable of sending control signals to the glow plug control unit according to the sensor signals;

[0017] The glow plug control unit is capable of determining the number of glow plugs to be turned on for heating in each cycle according to the sum of the methanol temperature and the intake air temperature, and determining the time for the glow plugs to be turned on for heating according to the engine speed.

[0018] In an embodiment of the present application, further comprising a coolant temperature sensor, a methanol temperature sensor, an intake air temperature sensor and a crankshaft position sensor arranged on the methanol compression ignition engine and connected to the ECU control unit through a wire harness, the coolant temperature sensor, the methanol temperature sensor, the intake air temperature sensor and the crankshaft position sensor are capable of correspondingly obtaining the coolant temperature signal, the methanol temperature signal, the intake air temperature signal and the engine speed signal.

[0019] The present application further provides a control method for glow plugs of a pure methanol hot surface compression ignition engine, which utilizes the glow plug arrangement structure of the large-bore methanol hot surface compression ignition engine, and the control method comprises:

[0020] Receiving sensor signals from the methanol compression ignition engine, the sensor signals including a coolant temperature signal, a methanol temperature signal, an intake air temperature signal and an engine speed signal, and correspondingly obtaining the coolant temperature, the methanol temperature, the intake air temperature and the engine speed according to the sensor signals;

[0021] In response to the coolant temperature being less than a preset temperature threshold, determining that the methanol compression ignition engine is cold started, and controlling all the glow plugs to continuously heat in each cycle;

[0022] In response to the coolant temperature being greater than or equal to the preset temperature threshold, determining the number of glow plugs to be turned on for heating in each cycle according to the sum of the methanol temperature and the intake air temperature, and determining the time for the glow plugs to be turned on for heating according to the engine speed.

[0023] In an embodiment of the present application, determining the number of glow plugs to be turned on for heating in each cycle according to the sum of the methanol temperature and the intake air temperature comprises:

[0024] When the sum of the methanol temperature and the intake air temperature is less than a first temperature threshold, turning on all the glow plugs;

[0025] When the sum of the methanol temperature and the intake air temperature is greater than or equal to the first temperature threshold and less than a second temperature threshold, turning on a part of the number of glow plugs;

[0026] When the sum of the methanol temperature and the intake air temperature is greater than the second temperature threshold, none of the glow plugs is turned on.

[0027] In an embodiment of the present application, the time for turning on the glow plug heating is determined according to the engine speed, comprising:

[0028] The time for turning on the glow plug heating in each cycle is graded according to the engine speed.

[0029] In an embodiment of the present application, the time for turning on the glow plug heating in each cycle is graded according to the engine speed, comprising:

[0030] When the engine speed is greater than or equal to a first speed threshold and less than a second speed threshold, the time for turning on the glow plug heating is controlled to be a first duration;

[0031] When the engine speed is greater than or equal to the second speed threshold and less than a third speed threshold, the time for turning on the glow plug heating is controlled to be a second duration;

[0032] When the engine speed is greater than or equal to the third speed threshold and less than a fourth speed threshold, the time for turning on the glow plug heating is controlled to be a third duration.

[0033] The present application also provides a pure methanol hot surface compression ignition engine glow plug control system, comprising:

[0034] An ECU control unit is configured to receive sensor signals from the methanol compression ignition engine, the sensor signals including a coolant temperature signal, a methanol temperature signal, an intake air temperature signal, and a speed signal, and to obtain the coolant temperature, the methanol temperature, the intake air temperature, and the engine speed according to the sensor signals.

[0035] A cold start judgment unit is configured to judge whether the coolant temperature is less than a preset temperature threshold.

[0036] A glow plug control unit is configured to determine that the methanol compression ignition engine is cold started in response to the coolant temperature being less than the preset temperature threshold, and to control all the glow plugs to continuously heat in each cycle; and to determine the number of the glow plugs turned on for heating in each cycle according to the sum of the methanol temperature and the intake air temperature, and to determine the time for turning on the glow plug heating according to the engine speed in response to the coolant temperature being greater than or equal to the preset temperature threshold.

[0037] The above technical solutions of the present application have the following advantages compared with the prior art:

[0038] The pure methanol hot face compression ignition engine glow plug arrangement structure, method and system optimize the spray and flame propagation path: the distance between the multiple glow plugs and the methanol injector, the arrangement interval angle around the methanol injector and the extension length of the glow plug are accurately designed. Through the optimization of these key parameters, the penetration effect of the spray in the cylinder is improved, the methanol and air can be more fully and uniformly mixed, and the flame propagation path is optimized to ensure that the combustion process is more efficient and stable, and the problems of insufficient and unstable combustion caused by blocked spray, locally thick or thin mixture, etc. are avoided.

[0039] The application realizes precise matching of heating power and working conditions: based on the changes of methanol temperature, intake air temperature, coolant temperature and other parameters of the engine at different speeds, a coupling control model is constructed. According to the real-time working condition, the heating time and number of the glow plug are accurately controlled, so that the heating time of the glow plug is accurately matched with the actual operation demand of the engine. During cold start, the temperature of the glow plug can be quickly raised to promote the full evaporation of methanol and solve the problem of cold start difficulty; during engine operation, whether in high temperature, high load or other working condition changes, the temperature of the glow plug can always be in the best state, avoiding abnormal combustion, misfire and other combustion instability phenomena caused by improper temperature control of the glow plug, prolonging the service life of key components such as piston and connecting rod, reducing maintenance cost, and improving the overall performance and reliability of the engine.

[0040] The application adopts multiple glow plugs for symmetrical distributed arrangement, which aims to optimize the spray penetration and flame propagation path in the large-bore methanol engine, make the methanol and air mix more uniformly, and improve the combustion stability.

[0041] The distribution position and depth length of the glow plug are specially designed according to the cylinder diameter of the methanol engine and the characteristics of the methanol injector. Different cylinder diameters and methanol injector characteristics will result in different spray forms and distributions, and reasonable glow plug position design can ensure that the glow plug effectively acts on the methanol spray and avoid local overheating or insufficient heating.

[0042] In addition, the application has the following advantages through dynamic control of the heating time and number of the glow plug:

[0043] Each glow plug can be controlled to heat separately and can be maintained for a long time. The required temperature of the glow plug can be adjusted according to the specific working condition requirements of the engine to realize reliable ignition of methanol;

[0044] The coolant temperature is used as the basis for judging whether it is cold start. During cold start, the heating module of all glow plugs is turned on and continuously heated to solve the problem of cold start difficulty of large-bore methanol engine;

[0045] The number of electric heat plugs that are turned on for heating is determined according to the methanol temperature and the intake air temperature, and the methanol temperature and the intake air temperature directly affect the temperature of the mixed gas, so that the heating amount can be accurately matched with the actual heating demand of the engine by reasonably adjusting the number of electric heat plugs that are turned on for heating.

[0046] The heating time of the electric heat plug is controlled in multiple gears according to the rotating speed of the methanol engine. The heating time is divided into three gears according to different rotating speeds, so that the temperature of the electric heat plug can be more finely adjusted, and abnormal combustion, misfire and other combustion instability phenomena caused by improper temperature control can be avoided.

[0047] The present application optimizes the distance, arrangement interval angle and extension length of multiple electric heat plugs and methanol injectors, optimizes the spray penetration and flame propagation path, avoids spray obstruction, reduces the formation of local over-concentration area, makes the mixed gas mixing more uniform, and the combustion process more stable. Coupling control of the heating time and number of electric heat plugs based on engine rotating speed, intake air temperature, methanol temperature, coolant temperature and other parameters, realizes accurate matching of the temperature of the electric heat plug and the operating condition of the engine, effectively solves the cold start difficulty and combustion instability problem of the large-bore methanol engine, reduces the risk of abnormal combustion caused by knocking, improves the combustion stability, reduces the fatigue damage of the piston, connecting rod and other key components, prolongs the service life of the key components of the engine, reduces the maintenance cost, improves the energy utilization efficiency, reduces the methanol consumption, enhances the economic benefit and environmental friendliness of the engine. BRIEF DESCRIPTION OF DRAWINGS

[0048] In order to make the content of the present application more easily understood, the present application will be further described in detail below according to the specific embodiments of the present application and in conjunction with the drawings.

[0049] Figure 1 It is a bottom view of the symmetrical arrangement of multiple electric heat plugs of the large-bore methanol compression ignition engine in the present application from the direction of the cylinder head bottom.

[0050] Figure 2 It is a front view of the symmetrical arrangement of multiple electric heat plugs of the large-bore methanol compression ignition engine in the present application.

[0051] Figure 3 It is an electric control schematic diagram of the large-bore methanol compression ignition engine in the present application.

[0052] Figure 4 It is an electric heat plug heating control flow chart of the large-bore methanol compression ignition engine in the present application.

[0053] DESCRIPTION OF DRAWINGS

[0054] 1, electric heat plug; 2, methanol injector; 3, combustion chamber; 4, cylinder head base; 5, valve base. DETAILED DESCRIPTION

[0055] The present application will be further described below in conjunction with the drawings and specific embodiments so that those skilled in the art can better understand and implement the present application, but the embodiments are not intended to limit the present application.

[0056] In the present application, if the directions (up, down, left, right, front and back) are described, it is only for the convenience of describing the technical solutions of the present application, and is not intended to indicate or imply that the indicated technical features must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present application.

[0057] In the present application, the meaning of "several" is one or more, and the meaning of "multiple" is two or more. "Greater than", "less than", "exceeding" and the like are understood as not including the number; "above", "below", "within" and the like are understood as including the number. In the description of the present application, if "first" and "second" are described, it is only for the purpose of distinguishing technical features, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features or the sequence of indicated technical features.

[0058] In the present application, unless otherwise explicitly limited, the words "set", "install", "connect" and the like should be broadly understood, for example, they can be directly connected, or indirectly connected through an intermediate medium; can be fixedly connected, or can be detachably connected, or can be integrally formed; can be mechanically connected, or can be electrically connected or capable of communicating with each other; can be the communication or interaction relationship between two elements or the interaction relationship between two elements. The skilled in the art can reasonably determine the specific meaning of the above words in the present application in combination with the specific content of the technical solutions.

[0059] Example 1

[0060] Referring to Figures 1 to 3 As shown in the figure, the pure methanol hot surface compression ignition engine glow plug arrangement structure comprises:

[0061] An ECU control unit is used to receive sensor signals from the methanol compression ignition engine, the sensor signals including coolant temperature signals, methanol temperature signals, intake temperature signals and speed signals, and the ECU control unit acquires coolant temperature, methanol temperature, intake temperature and engine speed according to the sensor signals;

[0062] An electric glow plug control unit is connected to the ECU control unit;

[0063] A cylinder is provided with a combustion chamber 3 for mixing and burning methanol and air;

[0064] A cylinder head base 4 is arranged on the cylinder;

[0065] a methanol injector 2 installed in the center of the cylinder head base 4 and extending into the combustion chamber 3 to inject methanol fuel into the combustion chamber 3;

[0066] a plurality of valve bases 5 installed on the cylinder head base 4 and capable of communicating with the combustion chamber 3, the plurality of valve bases 5 being centrally symmetrically distributed around the methanol injector 2;

[0067] a single or multiple glow plugs 1 installed on the cylinder head base 4 and located in the area between the valve bases 5 and the methanol injector 2, and when multiple glow plugs 1 are present, they are centrally symmetrically distributed around the methanol injector 2, and the heating portion of each glow plug 1 extends into the combustion chamber 3;

[0068] The ECU control unit can send control signals to the glow plug control unit according to the sensor signals.

[0069] The glow plug control unit can determine the number of times the glow plug 1 is turned on for heating in each cycle according to the sum of the methanol temperature and the intake air temperature, and determine the time for which the glow plug 1 is turned on for heating according to the engine speed.

[0070] Specifically, referring to Figure 3 The cooling liquid temperature sensor, the methanol temperature sensor, the intake air temperature sensor, and the crankshaft position sensor are connected to the ECU control unit through a wiring harness, and can correspondingly obtain cooling liquid temperature signals, methanol temperature signals, intake air temperature signals, and speed signals.

[0071] By way of example, the above arrangement is applicable to a large-bore marine methanol single-fuel compression ignition engine with a displacement of 69 liters, a cylinder diameter of 225 mm, and six cylinders.

[0072] Referring to Figure 1 The methanol injector 2 is located at the center of the cylinder head base 4, the four valve bases 5 are centrally symmetrically distributed on the cylinder head base 4, the methanol injector 2 is located at the center of the cylinder head base 4, the four glow plugs 1 are located in the area between the four valve bases 5 and the methanol injector 2, and are also centrally symmetrically distributed around the center of the cylinder, the distance between the center of each glow plug 1 and the center of the methanol injector 2 is L, and the specific value of L is determined according to the engine cylinder diameter, displacement, and injection characteristics of the methanol injector 2.

[0073] Referring to Figure 2As shown, the depth of the methanol nozzle of the methanol injector 2 into the combustion chamber 3 is h1, and the depth of the heating part of each glow plug 1 into the combustion chamber 3 is h2, wherein the depth of h2 is determined according to the distance L between the center of each glow plug 1 and the center of the methanol injector 2 and the depth h1 of the methanol nozzle into the combustion chamber 3.

[0074] It should be noted that the arrangement interval angle of the plurality of glow plugs 1 is consistent with the interval angle of the injection holes of the methanol injector 2. The distance L between the center of the glow plug 1 and the center of the methanol injector 2 is related to the liquid phase penetration distance of the methanol spray under different kinds of engine thermodynamic conditions, and L should be greater than the maximum liquid phase penetration distance of the methanol spray. Preferably, L is controlled within the range of greater than 18 mm and less than 30 mm.

[0075] The depth h2 of the heating part of the glow plug 1 into the combustion chamber 3 is affected by the compression ratio of the engine and the spray distribution of the methanol injector 2. Under the premise of ensuring that it does not hit the engine combustion chamber, the glow plug 1 should be as far as possible to maximize the area of contact with the methanol spray, thereby optimizing the heating effect. Preferably, 12 mm > h2 > 8 mm.

[0076] By reasonably setting the sizes of L and h2, the contact area of the glow plug with the methanol spray is as large as possible, the heating effect is enhanced, and at the same time, the combustion chamber structure is not disturbed, ensuring the working efficiency and stability of the entire system.

[0077] The above four glow plugs 1 are only for the arrangement of a large-bore marine methanol single-fuel compression-ignition engine with a displacement of 69 liters, a cylinder diameter of 225 mm, and six cylinders. Different numbers N of glow plugs 1 (for example, two, four, six, etc.) can be arranged symmetrically based on different displacements, different cylinder diameters, and different numbers of cylinders for large-bore marine methanol single-fuel compression-ignition engines.

[0078] Referring to Figure 4 As shown, the embodiment also provides a glow plug control method for a pure methanol hot surface compression-ignition engine. The control method comprises the following steps:

[0079] S1, receiving a sensor signal from the methanol compression-ignition engine, the sensor signal comprising a coolant temperature signal, a methanol temperature signal, an intake air temperature signal, and a rotational speed signal; and obtaining the coolant temperature t 冷却液 , the methanol temperature t 甲醇 , the intake air temperature t 进气 , and the engine rotational speed n 转速 according to the sensor signal.

[0080] S2, in response to the coolant temperature being less than a preset temperature threshold, determining that the methanol compression ignition engine is cold started, and controlling all of the glow plugs 1 to continuously heat in each cycle.

[0081] Exemplarily, the preset temperature threshold is 60℃.

[0082] S3, in response to the coolant temperature being greater than or equal to the preset temperature threshold, determining the number of the glow plugs 1 to be turned on to heat in each cycle according to the sum of the methanol temperature and the intake air temperature, and determining the time for the glow plugs 1 to be turned on to heat according to the engine speed.

[0083] Specifically, determining the number of the glow plugs 1 to be turned on to heat in each cycle according to the sum of the methanol temperature and the intake air temperature comprises:

[0084] when the sum of the methanol temperature and the intake air temperature is less than a first temperature threshold, turning on all of the glow plugs 1;

[0085] when the sum of the methanol temperature and the intake air temperature is greater than or equal to the first temperature threshold and less than a second temperature threshold, turning on a part of the number of the glow plugs 1;

[0086] when the sum of the methanol temperature and the intake air temperature is greater than the second temperature threshold, not turning on any of the glow plugs 1.

[0087] Exemplarily, when t 甲醇 +t 进气 < 70℃, the number of the glow plugs 1 to be turned on is N;

[0088] when 70℃ ≤ t 甲醇 +t 进气 < 90℃, the number of the glow plugs 1 to be turned on is greater than or equal to 1 and less than N;

[0089] when t 甲醇 +t 进气 ≥ 90℃, none of the glow plugs 1 is turned on.

[0090] Specifically, determining the time for the glow plugs 1 to be turned on to heat according to the engine speed comprises: grading the time for the glow plugs 1 to be turned on to heat in each cycle according to the engine speed, comprising:

[0091] when the engine speed is greater than or equal to a first speed threshold and less than a second speed threshold, controlling the time for the glow plugs 1 to be turned on to heat to be a first time length;

[0092] when the engine speed is greater than or equal to the second speed threshold and less than a third speed threshold, controlling the time for the glow plugs 1 to be turned on to heat to be a second time length;

[0093] When the engine speed is greater than or equal to the third speed threshold and less than a fourth speed threshold, the time for which the glow plug 1 is controlled to be turned on and heated is a third time length.

[0094] Exemplarily, each cycle T is a fixed time, which can be 10s.

[0095] When 400rpm≤n 转速 <600rpm, the time length for which the glow plug 1 is turned on and heated is T1; when 600rpm≤n 转速 <800rpm, the time length for which the glow plug 1 is turned on and heated is T2; when 800rpm≤n 转速 <1000rpm, the time length for which the glow plug 1 is turned on and heated is T3.

[0096] In each cycle T, the glow plug 1 is turned on and heated only in the above heating time T1, T2 or T3 stage, and remains in the off state for the rest of the time (T-T1, T-T2 or T-T3).

[0097] Embodiment 2

[0098] Based on the same inventive concept, the embodiment provides a glow plug control system for a pure methanol hot surface compression ignition engine, which solves the problem in a similar principle to the method for controlling the glow plug 1 of the large-bore methanol hot surface compression ignition engine, and the repeated parts will not be described again.

[0099] The embodiment provides a glow plug control system for a pure methanol hot surface compression ignition engine, comprising:

[0100] An ECU control unit is configured to receive sensor signals from the methanol compression ignition engine, the sensor signals including a coolant temperature signal, a methanol temperature signal, an intake air temperature signal and a speed signal, and to obtain the coolant temperature, the methanol temperature, the intake air temperature and the engine speed according to the sensor signals.

[0101] A cold start judgment unit is configured to judge whether the coolant temperature is less than a preset temperature threshold.

[0102] A glow plug control unit is configured to determine that the methanol compression ignition engine is in cold start when the coolant temperature is less than the preset temperature threshold, and to control all the glow plugs 1 to be continuously heated in each cycle; and to determine the number of times that the glow plug 1 is turned on and heated in each cycle according to the sum of the methanol temperature and the intake air temperature, and to determine the time for which the glow plug 1 is turned on and heated according to the engine speed, when the coolant temperature is greater than or equal to the preset temperature threshold.

[0103] Those skilled in the art will appreciate that embodiments of the present application can be readily used as a method, a system or a computer program product. Accordingly, the present application can take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present application can take the form of a computer program product on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROMs, optical storage devices, etc.) embodying computer readable program code.

[0104] The present application is described in reference to the flowchart and / or block diagrams of the method, apparatus (system) and computer program product according to embodiments of the present application. It will be understood that each block of the flowchart and / or block diagrams, and combinations of blocks in the flowchart and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general purpose computer, special purpose computer, embedded processing device or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart and / or block diagram block or blocks. Figure 1 one or more functions specified in the flowchart and / or block diagram block or blocks. Figure 1 one or more functions specified in the flowchart and / or block diagram block or blocks.

[0105] These computer program instructions can also be stored in a computer- readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instructions which implement the function specified in the flowchart and / or block diagram block or blocks. Figure 1 one or more functions specified in the flowchart and / or block diagram block or blocks. Figure 1 one or more functions specified in the flowchart and / or block diagram block or blocks.

[0106] These computer program instructions can also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart and / or block diagram block or blocks. Figure 1 one or more functions specified in the flowchart and / or block diagram block or blocks. Figure 1 one or more functions specified in the flowchart and / or block diagram block or blocks.

[0107] Finally, it should be noted that the detailed description of the specific embodiments is intended to be illustrative in nature and is not intended to be limiting. Although specific examples have been provided in the above description, those skilled in the art will understand that various modifications and equivalents can be used without departing from the spirit and scope of the application.

Claims

1. A glow plug arrangement for a pure methanol hot surface compression ignition engine, characterized in that The pure methanol hot surface compression ignition engine comprises: an ECU control unit for receiving sensor signals from the methanol compression ignition engine, the sensor signals comprising a coolant temperature signal, a methanol temperature signal, an intake air temperature signal and a rotation speed signal, the ECU control unit correspondingly acquiring coolant temperature, methanol temperature, intake air temperature and engine rotation speed according to the sensor signals; an electric glow plug control unit connected to the ECU control unit; a cylinder provided with a combustion chamber for mixing and combusting methanol and air; a cylinder head base arranged on the cylinder; a methanol injector mounted at the center of the cylinder head base and extending into the combustion chamber to inject methanol fuel into the combustion chamber; a plurality of valve seats mounted on the cylinder head base and capable of communicating with the combustion chamber, the plurality of valve seats being centrally symmetrically distributed around the methanol injector; one or more electric glow plugs mounted on the cylinder head base and located in the area between the valve seats and the methanol injector, the heating part of each electric glow plug extending into the combustion chamber; wherein the ECU control unit can send control signals to the electric glow plug control unit according to the sensor signals; the electric glow plug control unit can determine the number of electric glow plugs turned on for heating in each cycle according to the sum of the methanol temperature and the intake air temperature, and determine the time for the electric glow plugs to be turned on for heating according to the engine rotation speed.

2. The pure methanol hot surface compression ignition engine glow plug arrangement of claim 1, wherein, The pure methanol hot surface compression ignition engine further comprises a coolant temperature sensor, a methanol temperature sensor, an intake air temperature sensor and a crankshaft position sensor arranged on the methanol compression ignition engine and connected to the ECU control unit through a wire harness, the coolant temperature sensor, the methanol temperature sensor, the intake air temperature sensor and the crankshaft position sensor can correspondingly acquire the coolant temperature signal, the methanol temperature signal, the intake air temperature signal and the rotation speed signal.

3. A glow plug control method for a pure methanol hot surface ignition engine, characterized by, The control method using the pure methanol hot surface compression ignition engine electric glow plug arrangement structure of any one of claims 1-2 comprises: receiving sensor signals from the methanol compression ignition engine, the sensor signals comprising a coolant temperature signal, a methanol temperature signal, an intake air temperature signal and a rotation speed signal, correspondingly acquiring coolant temperature, methanol temperature, intake air temperature and engine rotation speed according to the sensor signals; in response to the coolant temperature being less than a preset temperature threshold, determining that the methanol compression ignition engine is cold started, and controlling all the electric glow plugs to continuously heat in each cycle; in response to the coolant temperature being greater than or equal to the preset temperature threshold, determining the number of electric glow plugs turned on for heating in each cycle according to the sum of the methanol temperature and the intake air temperature, and determining the time for the electric glow plugs to be turned on for heating according to the engine rotation speed.

4. A glow plug control method for a pure methanol hot surface compression ignition engine according to claim 3, characterized in that, determining the number of electric glow plugs turned on for heating in each cycle according to the sum of the methanol temperature and the intake air temperature comprises: when the sum of the methanol temperature and the intake air temperature is less than a first temperature threshold, turning on all the electric glow plugs; when the sum of the methanol temperature and the intake air temperature is greater than or equal to the first temperature threshold and less than a second temperature threshold, turning on a portion of the glow plugs; when the sum of the methanol temperature and the intake air temperature is greater than the second temperature threshold, not turning on any of the glow plugs.

5. A glow plug control method for a pure methanol hot surface compression ignition engine according to claim 3, wherein determining the time for turning on the glow plugs to heat according to the engine speed, comprising: grading the time for turning on the glow plugs to heat in each cycle according to the engine speed.

6. A glow plug control method for a pure methanol hot surface compression ignition engine according to claim 5, characterized in that, grading the time for turning on the glow plugs to heat in each cycle according to the engine speed, comprising: when the engine speed is greater than or equal to a first speed threshold and less than a second speed threshold, controlling the time for turning on the glow plugs to heat as a first time length; when the engine speed is greater than or equal to the second speed threshold and less than a third speed threshold, controlling the time for turning on the glow plugs to heat as a second time length; when the engine speed is greater than or equal to the third speed threshold and less than a fourth speed threshold, controlling the time for turning on the glow plugs to heat as a third time length.

7. A glow plug control system for a pure methanol hot surface ignition engine, comprising: applied to the glow plug arrangement structure of the pure methanol hot surface compression ignition engine of any one of claims 1-2, comprising: an ECU control unit for receiving sensor signals from the methanol compression ignition engine, the sensor signals including a coolant temperature signal, a methanol temperature signal, an intake air temperature signal and a speed signal, and correspondingly acquiring the coolant temperature, the methanol temperature, the intake air temperature and the engine speed according to the sensor signals; a cold start judgment unit for judging whether the coolant temperature is less than a preset temperature threshold; a glow plug control unit for determining that the methanol compression ignition engine is cold started in response to the coolant temperature being less than the preset temperature threshold, and controlling all of the glow plugs to continuously heat in each cycle; and in response to the coolant temperature being greater than or equal to the preset temperature threshold, determining the number of the glow plugs to turn on to heat in each cycle according to the sum of the methanol temperature and the intake air temperature, and determining the time for turning on the glow plugs to heat according to the engine speed.

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