Temperature control method and device for glow plug of methanol engine

Abstract

The invention discloses a methanol engine glow plug temperature control method and device, and relates to the field of engine glow plug temperature control. The control method comprises the steps that the rotating speed of a target engine, the methanol real-time injection amount and the glow plug real-time temperature are obtained; the optimal temperature of the glow plug is obtained according to the rotating speed and the real-time methanol injection amount; and performing temperature compensation on the glow plug according to a difference value between the real-time temperature of the glow plug and the optimal temperature of the glow plug. According to the control method, dynamic accurate closed-loop control over the temperature of the glow plug at different rotating speeds of the engine and the methanol temperature of the methanol injection amount is effectively achieved, it is guaranteed that dynamic combustion of methanol fuel in an engine cylinder is optimal, and efficient and clean utilization of the methanol fuel on the engine is assisted. The control device comprises an electronic control unit, a glow plug and a rotating speed sensor, the electronic control unit is used for executing the steps of the control method, the glow plug is used for temperature compensation in an engine combustion chamber, and the rotating speed sensor is used for obtaining the rotating speed of the engine.

Description

Technical Field

[0001] The present invention relates to the technical field of engine glow plug temperature control, and more specifically, to a method and device for controlling the temperature of a methanol engine glow plug. Background Art

[0002] Methanol fuel is considered to be a very promising alternative energy source due to its good anti-knock performance, fast flame propagation speed, high oxygen content, complete combustion, low harmful emissions, and abundant production. However, methanol fuel has a low cetane number and high ignition temperature, and is difficult to spontaneously ignite in a compression ignition engine, requiring a series of auxiliary measures to help it burn.

[0003] As one of the commonly used measures, the glow plug combustion assistance of the engine mainly solves the problems of high latent heat of vaporization and high compression ignition temperature of methanol fuel by heating the engine intake air, so as to achieve stable combustion of methanol fuel in the engine. The glow plug combustion assistance mainly optimizes the combustion in the cylinder by adjusting the temperature of the heating element.

[0004] The current glow plug temperature control mainly achieves combustion optimization at a fixed engine operating point by manually adjusting the glow plug temperature. The existing glow plugs have achieved the requirement of adjustable temperature function, but cannot meet the demand for dynamic and precise control of glow plug temperature according to changes in engine speed and load, and cannot meet the demand for dynamic and precise adjustment of glow plug temperature according to changes in engine operating conditions, which limits the efficient and clean combustion of methanol fuel in ship engines.

[0005] In summary, how to achieve dynamic and precise adjustment of the glow plug temperature according to changes in engine operating conditions is an urgent problem to be solved by those skilled in the art. Summary of the invention

[0006] In view of this, the purpose of the present invention is to provide a method and device for controlling the temperature of the glow plug in a methanol engine, which effectively realizes the dynamic and precise closed-loop control of the glow plug temperature at different engine speeds and methanol injection amounts, ensures that the dynamic combustion of methanol fuel in the engine cylinder is optimal, and helps to efficiently and cleanly utilize methanol fuel in the engine.

[0007] In order to achieve the above object, the present invention provides the following technical solutions:

[0008] A method for controlling the temperature of a methanol engine glow plug, the control method comprising:

[0009] Obtain the target engine's speed, methanol real-time injection volume, and glow plug real-time temperature;

[0010] obtaining an optimal temperature of the glow plug according to the rotation speed and the real-time injection amount of methanol;

[0011] The temperature of the glow plug is compensated according to the difference between the real-time temperature of the glow plug and the optimal temperature of the glow plug.

[0012] Preferably, the step of obtaining the speed of the target engine, the real-time methanol injection amount and the real-time temperature of the glow plug comprises:

[0013] By setting a speed sensor, the speed of the target engine is collected according to the speed sensor;

[0014] The real-time methanol injection amount is collected through the engine electronic control unit;

[0015] The real-time temperature of the glow plug is obtained through the engine electronic control unit.

[0016] Preferably, the step of obtaining the optimal temperature of the glow plug according to the rotation speed and the real-time methanol injection amount comprises:

[0017] respectively obtaining and determining the range of the rotation speed and the real-time injection amount of methanol;

[0018] Creating a preset calibration MAP two-dimensional grid, wherein the horizontal axis is used to represent the rotation speed, the vertical axis is used to represent the real-time methanol injection amount, and each grid point is used to represent the optimal temperature of the glow plug;

[0019] Based on the preset calibrated MAP two-dimensional grid, the optimal temperature of the glow plug is obtained.

[0020] Preferably, the real-time methanol injection amount adopts the methanol injection amount per cylinder or the methanol injection amount per cycle.

[0021] Preferably, the methanol injection amount per cycle can be replaced by the injection time of methanol per cycle.

[0022] Preferably, the step of performing temperature compensation on the glow plug according to the difference between the real-time temperature of the glow plug and the optimal temperature of the glow plug comprises:

[0023] calculating a temperature difference between the real-time temperature of the glow plug and the optimal temperature of the glow plug;

[0024] adjusting the current of the glow plug according to the temperature difference to achieve temperature compensation;

[0025] When the real-time temperature of the glow plug is lower than the optimal temperature of the glow plug, increasing the current of the glow plug to increase the temperature of the glow plug and reach the optimal temperature of the glow plug;

[0026] When the real-time temperature of the glow plug is higher than the optimal temperature of the glow plug, reducing the current of the glow plug to cool the glow plug to the optimal temperature of the glow plug;

[0027] The temperature closed-loop control is performed by an electronic control unit to ensure that the temperature of the glow plug quickly and accurately reaches the optimal temperature of the glow plug.

[0028] Preferably, the control method further includes:

[0029] During the temperature compensation process of the glow plug, the current change of the glow plug is monitored in real time.

[0030] A methanol engine glow plug temperature control device, comprising:

[0031] An electronic control unit, the electronic control unit is used to execute the steps of any one of the control methods described above;

[0032] A glow plug, the glow plug is used for temperature compensation in the engine combustion chamber, the glow plug is electrically connected to the electronic control unit;

[0033] A rotation speed sensor is arranged on the engine, and is used to obtain the rotation speed of the engine. The rotation speed sensor is electrically connected to the electronic control unit.

[0034] Preferably, the glow plug is arranged on an intake manifold or an intake branch pipe outside the combustion chamber of the engine.

[0035] Preferably, the glow plug is disposed in a combustion chamber of the engine, and a specific location in the combustion chamber includes but is not limited to a cylinder wall or a cylinder head.

[0036] The method for controlling the temperature of a glow plug in a methanol engine provided by the present invention comprises obtaining the rotation speed of a target engine, a real-time methanol injection amount and a real-time temperature of a glow plug; obtaining an optimal temperature of the glow plug according to the rotation speed and the real-time methanol injection amount; and performing temperature compensation on the glow plug according to the difference between the real-time temperature of the glow plug and the optimal temperature of the glow plug.

[0037] The methanol engine glow plug temperature control method provided in the present application determines the optimal temperature of the glow plug through the speed of the target engine and the real-time methanol injection amount, and obtains the difference by comparing it with the real-time temperature of the glow plug, thereby performing temperature compensation, thereby effectively realizing dynamic and precise closed-loop control of the glow plug temperature at different engine speeds and methanol injection amounts, ensuring that the dynamic combustion of methanol fuel in the engine cylinder is optimal, and facilitating the efficient and clean use of methanol fuel in the engine. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0039] Figure 1 Schematic diagram of the steps of the method for controlling the temperature of the glow plug of a methanol engine in this embodiment;

[0040] Figure 2 This is a schematic diagram of step S1 in this embodiment;

[0041] Figure 3 This is a schematic diagram of step S2 in this embodiment;

[0042] Figure 4 This is a schematic diagram of step S3 in this embodiment;

[0043] Figure 5 Schematic diagram of the structure of the methanol engine glow plug temperature control device in this embodiment.

[0044] Figure 1-Figure 5 , the reference numerals include:

[0045] 1. Glow plug; 2. Electronic control unit; 3. Speed ​​sensor; 4. Engine. DETAILED DESCRIPTION

[0046] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0047] Unless otherwise defined, the technical terms or scientific terms used in the present application shall have the usual meanings understood by persons with ordinary skills in the field to which the invention belongs. The words "first", "second" and similar words used in the present invention do not indicate any order, quantity or importance. Words such as "connected" or "connected" are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative position relationships. When the absolute position of the object being described changes, the relative position relationship may also change accordingly. The embodiment of the present application discloses a method and device for controlling the temperature of a methanol engine glow plug.

[0048] The core of the present invention is to provide a method and device for controlling the temperature of a methanol engine glow plug.

[0049] Please refer to Figures 1 to 4 .

[0050] The method for controlling the temperature of the methanol engine glow plug provided by the present invention comprises:

[0051] S1, obtaining the rotation speed of the target engine 4, the real-time methanol injection amount and the real-time temperature of the glow plug 1;

[0052] S2, obtaining the optimal temperature of the glow plug 1 according to the rotation speed and the real-time methanol injection amount;

[0053] S3. Perform temperature compensation on the glow plug according to the difference between the real-time temperature of the glow plug and the optimal temperature of the glow plug.

[0054] Specifically, during the operation of the actual ship, the load and speed of the engine 4 need to change dynamically according to the navigation conditions. The existing glow plug temperature is only set according to fixed conditions, which only satisfies the stable operation of the engine 4 in a narrow operating load range, limiting the combustion optimization of the engine 4 under different speeds and load conditions of the engine 4, and hindering the efficient combustion of methanol fuel in the engine 4. Through theoretical analysis and experimental research, the optimal temperature setting of the glow plug 1 is mainly affected by the engine speed and the methanol injection amount. In the operation of the actual ship, this method obtains the engine speed and the real-time methanol injection amount in real time, and obtains the corresponding optimal glow plug temperature through the engine speed and the real-time methanol injection amount. At the same time, the real-time temperature of the glow plug is obtained, and the difference between the real-time temperature of the glow plug and the optimal temperature of the glow plug is taken to perform temperature compensation on the glow plug, so as to realize dynamic automatic adjustment of the temperature of the methanol glow plug.

[0055] The above-mentioned methanol engine glow plug temperature control method determines the optimal temperature of the glow plug through the speed of the target engine and the real-time methanol injection amount, and obtains the difference by comparing it with the real-time temperature of the glow plug, thereby performing temperature compensation, thereby effectively realizing dynamic and precise closed-loop control of the glow plug temperature at different engine speeds and methanol injection amounts, ensuring that the dynamic combustion of methanol fuel in the engine cylinder is optimal, and facilitating the efficient and clean use of methanol fuel in the engine.

[0056] The methanol engine glow plug temperature control method provided by the present invention is described in more detail below with reference to the accompanying drawings and specific embodiments.

[0057] In a specific embodiment, reference Figure 2 , step S1 specifically includes:

[0058] S11, by setting the speed sensor 3, collecting the speed of the target engine 4 according to the speed sensor 3;

[0059] S12, collecting the real-time injection amount of methanol through the electronic control unit 2 of the engine 4;

[0060] S13 , obtaining the real-time temperature of the glow plug 1 through the electronic control unit 2 of the engine 4 .

[0061] Specifically, a speed sensor 3 is provided at the wheel of the engine 4 to collect the speed of the engine wheel 4 in real time, so as to obtain the data required in step S1, and the real-time injection amount of methanol is collected through the electronic control unit 2, so as to obtain the data required in step S1. The real-time temperature of the glow plug 1 is obtained according to the electronic control unit 2.

[0062] Based on any of the above embodiments, Figure 3 , step S2 specifically includes:

[0063] S21, respectively obtaining and determining the range of the rotation speed and the real-time methanol injection amount;

[0064] S22, creating a preset calibration MAP two-dimensional grid, wherein the horizontal axis is used to represent the rotation speed, the vertical axis is used to represent the real-time methanol injection amount, and each grid point is used to represent the optimal temperature of the glow plug;

[0065] S23. Obtaining the optimal temperature of the glow plug based on a preset calibrated MAP two-dimensional grid.

[0066] Table 1 Glow plug temperature control MAP

[0067] X-axis: engine speed, unit: r / min;

[0068] Y axis: methanol injection amount, unit: / cylinder / CYCLE;

[0069] Y / X 100 200 300 400 500 600 700 800 900 1000 400 800 800 800 800 800 800 800 800 800 1100 600 800 800 800 800 800 800 800 800 1000 1100 800 800 800 800 800 800 800 800 800 1000 1100 1000 800 800 800 800 800 800 800 800 1000 1100 1200 800 800 800 800 800 800 800 800 1000 1100 1400 800 800 800 800 800 800 800 800 1000 1100 1600 800 800 800 800 800 800 800 800 1000 1100 1800 800 800 800 800 800 800 800 800 1000 1100 2000 800 800 800 800 800 800 800 800 1000 1100 2200 800 800 800 800 800 800 800 800 1000 1100 2400 800 800 800 800 800 800 800 800 1000 1100 2600 800 800 800 800 800 800 800 800 1000 1100 2800 1000 1000 1000 1000 1000 1000 1000 1000 1000 1100 3000 1100 1100 1100 1100 1100 1100 1100 1100 1100 1100

[0070] Specifically, the speed and the range of the real-time methanol injection amount are obtained and determined first, so as to determine the value range of the horizontal and vertical coordinates, and then create a preset calibration MAP two-dimensional grid, in which the horizontal axis is used to represent the speed, the vertical axis is used to represent the real-time methanol injection amount, and each grid point is used to represent the optimal temperature of the glow plug (as shown in Table 1). Based on the preset calibration MAP two-dimensional grid, the optimal temperature of the glow plug is obtained corresponding to the obtained engine speed and the real-time methanol injection amount.

[0071] It should be noted that the glow plug temperature setting is calibrated by bench test. The glow plug temperature MAP is formed according to the engine speed and methanol injection amount. The glow plug temperature is calibrated by bench test. Test calibration often uses cylinder pressure sensor, single-row thermocouple, exhaust pollutant concentration measurement and other measures to calibrate the glow plug temperature value while taking into account the engine fuel consumption and emission pollutants to meet the regulatory requirements.

[0072] Furthermore, the real-time methanol injection amount adopts the methanol injection amount per cylinder or the methanol injection amount per cycle, wherein the methanol injection amount per cycle can be replaced by the injection time of methanol per cycle.

[0073] Specifically, the glow plug temperature calibration MAP uses the methanol injection amount per cycle as the calibration coordinate, and the methanol injection amount per cycle can be replaced by the methanol injection time per cycle. Methanol injection is generally controlled by a solenoid valve. After the methanol injector is determined, the methanol injection amount per cycle and the methanol injection time per cycle can be equivalently converted.

[0074] Based on any of the above embodiments, Figure 4 , step S3 specifically includes:

[0075] S31, calculating the temperature difference between the real-time temperature of the glow plug and the optimal temperature of the glow plug;

[0076] S32, adjusting the current of the glow plug according to the temperature difference to achieve temperature compensation. When the real-time temperature of the glow plug is lower than the optimal temperature of the glow plug, increasing the current of the glow plug to heat up the glow plug and reach the optimal temperature of the glow plug. When the real-time temperature of the glow plug is higher than the optimal temperature of the glow plug, reducing the current of the glow plug to cool down the glow plug to the optimal temperature of the glow plug.

[0077] S33. Perform temperature closed-loop control through the electronic control unit 2 to ensure that the temperature of the glow plug quickly and accurately reaches the optimal temperature of the glow plug.

[0078] Specifically, according to the temperature difference between the real-time temperature of the glow plug and the optimal temperature of the glow plug, the current of the glow plug 1 is adjusted to achieve temperature compensation of the glow plug 1. When the real-time temperature of the glow plug is lower than the optimal temperature of the glow plug, the current of the glow plug is increased to heat up the glow plug and reach the optimal temperature of the glow plug. When the real-time temperature of the glow plug is higher than the optimal temperature of the glow plug, the current of the glow plug is reduced to cool the glow plug to the optimal temperature of the glow plug. The electronic control unit 2 is coordinated to perform temperature closed-loop control to ensure that the temperature of the glow plug reaches the optimal temperature of the glow plug quickly and accurately.

[0079] In a specific embodiment provided in the present application, the methanol engine glow plug temperature control method provided by the present invention further includes, during the temperature compensation process of the glow plug 1, real-time monitoring of the current change of the glow plug.

[0080] Specifically, by monitoring the current change of the glow plug in real time during the temperature compensation process of the glow plug 1, an alarm system can be set up to trigger an alarm when there is an abnormal current change value, which can effectively prevent the glow plug from being damaged due to excessive current.

[0081] Please refer to Figure 5 .

[0082] The methanol engine glow plug temperature control device provided by the present invention includes an electronic control unit 2, a glow plug 1 and a speed sensor 3, the electronic control unit 2 is used to execute the steps of any of the above control methods, the glow plug 1 is used for temperature compensation in the combustion chamber of the engine 4, the glow plug 1 is electrically connected to the electronic control unit 2, the speed sensor 3 is arranged on the engine 4, the speed sensor 3 is used to obtain the speed of the engine 4, and the speed sensor 3 is electrically connected to the electronic control unit 2.

[0083] Specifically, with the help of the speed sensor 3 arranged on the engine 4, the speed of the engine 4 is obtained in real time. At the same time, with the help of the electronic control unit 2, the real-time injection amount of methanol can be obtained in real time. According to the obtained engine speed and the real-time injection amount of methanol, the optimal temperature of the glow plug 1 is determined. At the same time, the real-time temperature of the glow plug 1 is obtained again according to the electronic control unit 2. According to the difference between the real-time temperature of the glow plug 1 and the optimal temperature, the temperature of the glow plug 1 is compensated. This process can still be controlled by the electronic control unit 2, thereby realizing dynamic and automatic adjustment of the temperature of the methanol glow plug, further realizing the optimal temperature control of the methanol combustion in the engine cylinder, and realizing efficient and clean combustion of methanol in the engine cylinder.

[0084] Based on any one of the above embodiments, the glow plug 1 is arranged on the intake manifold or intake branch pipe outside the combustion chamber of the engine 4 .

[0085] Specifically, the glow plug 1 is installed in the intake manifold of the engine 4 and the intake branch pipes of each cylinder to heat the engine intake air and realize heat compensation in the process of methanol vaporization and heat absorption.

[0086] Based on any one of the above embodiments, the glow plug 1 is disposed in the combustion chamber of the engine 4, and the specific location in the combustion chamber includes but is not limited to the cylinder wall or the cylinder head.

[0087] Specifically, compared with setting the glow plug 1 on the intake manifold or intake branch pipe outside the combustion chamber of the engine 4, in terms of actual use effect, the glow plug 1 is installed in the combustion chamber to directly heat the methanol-air mixture, reducing the heat loss from heating the intake manifold and branch pipe, and at the same time avoiding the excessive temperature of the glow plug 1 that causes premature vaporization of methanol in the intake pipe, resulting in a reduction in the air intake volume in the cylinder and forming "air blockage". In-cylinder heating can avoid the above shortcomings and achieve the best effect.

[0088] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0089] The above is a detailed introduction to a methanol engine glow plug temperature control method and device provided by the present invention. This article uses specific examples to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea. It should be pointed out that for ordinary technicians in this technical field, without departing from the principle of the present invention, the present invention can also be improved and modified in a number of ways, and these improvements and modifications also fall within the scope of protection of the present invention.

Claims

1. A method for controlling the temperature of a methanol engine glow plug, characterized in that: The control method comprises: Obtain the target engine's speed, methanol real-time injection volume, and glow plug real-time temperature; obtaining an optimal temperature of the glow plug according to the rotation speed and the real-time injection amount of methanol; The temperature of the glow plug is compensated according to the difference between the real-time temperature of the glow plug and the optimal temperature of the glow plug.

2. A methanol engine glow plug temperature control method according to claim 1, characterized in that: The steps of obtaining the speed of the target engine, the real-time methanol injection amount, and the real-time temperature of the glow plug include: By setting a speed sensor, the speed of the target engine is collected according to the speed sensor; The real-time methanol injection amount is collected through the engine electronic control unit; The real-time temperature of the glow plug is obtained through the engine electronic control unit.

3. A methanol engine glow plug temperature control method according to claim 1, characterized in that: The step of obtaining the optimal temperature of the glow plug according to the rotation speed and the real-time methanol injection amount comprises: respectively obtaining and determining the range of the rotation speed and the real-time injection amount of methanol; Creating a preset calibration MAP two-dimensional grid, wherein the horizontal axis is used to represent the rotation speed, the vertical axis is used to represent the real-time methanol injection amount, and each grid point is used to represent the optimal temperature of the glow plug; Based on the preset calibrated MAP two-dimensional grid, the optimal temperature of the glow plug is obtained.

4. A methanol engine glow plug temperature control method according to claim 3, characterized in that: The real-time methanol injection amount adopts the methanol injection amount per cylinder or the methanol injection amount per cycle.

5. A methanol engine glow plug temperature control method according to claim 4, characterized in that: The methanol injection amount per cycle may be replaced by the injection time of methanol per cycle.

6. A methanol engine glow plug temperature control method according to claim 1, characterized in that: The step of performing temperature compensation on the glow plug according to the difference between the real-time temperature of the glow plug and the optimal temperature of the glow plug comprises: calculating a temperature difference between the real-time temperature of the glow plug and the optimal temperature of the glow plug; adjusting the current of the glow plug according to the temperature difference to achieve temperature compensation; When the real-time temperature of the glow plug is lower than the optimal temperature of the glow plug, increasing the current of the glow plug to increase the temperature of the glow plug and reach the optimal temperature of the glow plug; When the real-time temperature of the glow plug is higher than the optimal temperature of the glow plug, reducing the current of the glow plug to cool the glow plug to the optimal temperature of the glow plug; The temperature closed-loop control is performed by an electronic control unit to ensure that the temperature of the glow plug quickly and accurately reaches the optimal temperature of the glow plug.

7. A methanol engine glow plug temperature control method according to claim 6, characterized in that: The control method further comprises: During the temperature compensation process of the glow plug, the current change of the glow plug is monitored in real time.

8. A methanol engine glow plug temperature control device, characterized in that: include: An electronic control unit (2), the electronic control unit (2) being used to execute the steps of the control method according to any one of claims 1 to 7; A glow plug (1), the glow plug (1) being used for temperature compensation in a combustion chamber of an engine (4), the glow plug (1) being electrically connected to the electronic control unit (2); A rotation speed sensor (3) is arranged on the engine (4), the rotation speed sensor (3) is used to obtain the rotation speed of the engine (4), and the rotation speed sensor (3) is electrically connected to the electronic control unit (2).

9. A methanol engine glow plug temperature control device according to claim 8, characterized in that: The glow plug (1) is arranged on an intake manifold or an intake branch pipe outside a combustion chamber of the engine (4).

10. A methanol engine glow plug temperature control device according to claim 8, characterized in that: The glow plug (1) is arranged in the combustion chamber of the engine (4), and the specific arrangement position in the combustion chamber includes but is not limited to the cylinder wall or the cylinder head.

Images