KR20200008008A - Ship Engine and Method for Ship Engine - Google Patents

Abstract

The present invention relates to a vessel engine and a method for controlling a vessel engine, the method comprising: a step that the speed of revolution of a crank shaft is measured; a step that the amount of gas fuel is controlled corresponding to the measured speed of revolution of the crank shaft before being supplied to a cylinder, and the mixture of the gas fuel and air supplied to the cylinder is compressed and combusted; a step that a combustion pressure of the mixture combusted in the cylinder is measured; a step that an indicated mean effective pressure is calculated from the combustion pressure; a step that it is determined whether the calculated indicated mean effective pressure belongs to a predetermined reference indicated mean effective pressure range; a step that, when the value of the calculated indicated mean effective pressure is erroneous, or the value of the indicated mean effective pressure cannot be calculated, it is determined whether a scavenging pressure supplied to the cylinder is identical to an estimated scavenging pressure; a step that, when the scavenging pressure supplied to the cylinder is identical to the estimated scavenging pressure, the amount of the gas fuel supplied to the cylinder is determined; and a step that, when the scavenging pressure supplied to the cylinder is different from the estimated scavenging pressure, it is returned to the step that the amount of the gas fuel is controlled corresponding to the measured speed of revolution of the crank shaft.

Description

Ship engine and ship engine control method {Ship Engine and Method for Ship Engine}

The present invention relates to a marine engine and a marine engine control method for efficiently propelling a marine vessel.

Generally, marine engines include various engines such as diesel engines, gas turbine engines, and dual fuel engines. In particular, the dual fuel engine has two fuels. For example, due to the advantage that can be used in parallel with gas and diesel, it is widely used in ships.

Ships equipped with such dual fuel engines (hereinafter referred to as `` ships '') use one of the gas modes that generate propulsion driving force using gas as the main fuel and the diesel mode which generates propulsion driving force using diesel as the main fuel. To drive.

The dual fuel engine is installed on the cylinder, the piston reciprocating up and down in the cylinder, the cylinder cover installed on the upper side of the cylinder, the main cover injecting diesel fuel in the diesel mode, and the cylinder cover installed on the cylinder cover. Pilot injector to inject a small amount of diesel fuel to ignite the fuel, an exhaust valve installed in the cylinder cover to exhaust the exhaust gas from the cylinder, an exhaust receiver to receive the exhaust gas discharged from the cylinder, installed under the cylinder And a gas supply unit installed between the upper and lower sides of the cylinder to supply air into the cylinder, and supplying gas fuel into the cylinder. In addition, the dual fuel engine includes a turbocharger that increases the output of the engine by increasing the amount of air supplied to the cylinder by using the exhaust gas discharged from the cylinder. The air compressed by the turbocharger may be supplied to a small gas receiver and supplied to a cylinder.

On the other hand, in a conventional ship, in gas mode operation, the gas supply unit supplies gas fuel to the cylinder between the lower side and the upper side of the cylinder in the middle of the piston moving upward after supplying the gas from the lower side of the cylinder to the inside, and the piston is on the upper side. It further moves to generate the propulsion by compressing and burning the scavenge and gas fuel supplied to the cylinder.

Here, the amount of gas fuel supplied to the cylinder by the gas supply unit is controlled by the navigator operating the ship. For example, increasing the load of the engine to increase the speed of the vessel increases the amount of gas fuel supplied to the cylinder and the relatively low amount of air, thereby causing knocking and pre-ignition. There is a problem that the efficiency of the engine is lowered. On the contrary, when the load of the engine is lowered to reduce the speed of the ship, the amount of gas fuel supplied to the cylinder is reduced and the amount of air is relatively increased, resulting in misfiring and deterioration of engine efficiency. have. Therefore, there is a great need for a marine engine and a marine engine control method capable of supplying a cylinder by rapidly adjusting the amount of gas fuel according to the load of the engine.

The present invention has been made to solve the problems described above, and to provide a marine engine and a marine engine control method that can be supplied to the cylinder by quickly adjusting the amount of gas fuel in accordance with the load of the engine.

In order to solve the problems as described above, the present invention may include the following configuration.

The marine engine according to the present invention includes a cylinder for burning fuel; A piston installed in the cylinder so as to be movable upward and downward; A small receiver installed at a lower side of the cylinder to supply air to the cylinder; A gas supply part provided on a side wall of the cylinder to supply gas fuel to the cylinder; It may include a control unit for controlling the gas supply unit to adjust the amount of gas fuel supplied to the cylinder. The controller may determine the amount of gas fuel supplied to the cylinder by using at least one of a combustion pressure generated in the cylinder and a scavenging pressure of the scavenging receiver according to an engine load.

The marine engine according to the present invention may include a third measuring unit for measuring the combustion pressure of the cylinder. The controller receives the combustion pressure information of the cylinder measured multiple times from the third measuring unit to calculate the indicated average effective pressure (IMEP), and the calculated average measured effective pressure value is inconsistent with the predicted average measured effective pressure value. If the number of times consecutively N or more (N is an integer greater than 0) or more times, the amount of gas fuel supplied to the cylinder may be determined using the scavenging pressure of the scavenging receiver.

The marine engine according to the present invention includes a first measuring unit for measuring the rotational speed of the crankshaft of the engine, a second measuring unit for measuring the scavenging pressure stored in the scavenging receiver, and a third for measuring the combustion pressure of the cylinder. It may include a measuring unit. The controller may determine the amount of gas fuel supplied to the cylinder by receiving corresponding information from the first measuring unit, the second measuring unit, and the third measuring unit, respectively.

The marine engine according to the present invention may include an exhaust valve for discharging the exhaust gas generated by the compression and combustion of gas fuel and air in the cylinder from the cylinder. The third measuring unit may measure a combustion pressure generated when fuel is combusted after the exhaust valve closes the cylinder.

Marine engine control method according to the invention comprises the steps of measuring the rotational speed of the crankshaft; Adjusting the amount of gas fuel according to the measured rotation speed of the crankshaft to supply the cylinder, and compressing and combusting a mixture of gas fuel and air supplied to the cylinder; Measuring a combustion pressure of the mixture combusted in the cylinder; Calculating an indicated average effective pressure from the combustion pressure; Determining whether the calculated indicated average effective pressure falls within a predetermined reference average effective pressure range; Determining whether the scavenging pressure supplied to the cylinder is equal to the predicted scavenging pressure when the calculated indicated average effective pressure value is out of a predetermined reference indicator average effective pressure range; Determining an amount of gas fuel supplied to the cylinder when the scavenging pressure supplied to the cylinder is equal to a predicted scavenging pressure; And if the scavenging pressure supplied to the cylinder is different from the expected scavenging pressure, returning to the step of adjusting the amount of gas fuel according to the measured rotation speed of the crankshaft.

The ship engine control method according to the present invention comprises the steps of: determining whether the calculated indicated average effective pressure is equal to the predicted indicated average effective pressure if the calculated indicated average effective pressure falls within a preset reference average effective pressure range; Determining the amount of gas fuel supplied to the cylinder if the calculated indicated average effective pressure is equal to the predicted indicated average effective pressure; And returning to the step of adjusting the amount of gas fuel according to the measured rotational speed of the crankshaft if the calculated indicating average effective pressure is different from the predicted indicating average effective pressure.

The ship engine control method according to the present invention comprises the steps of: determining whether the number of consecutive mismatches is less than N (N is an integer greater than 0) if the calculated indicated average effective pressure is not equal to the predicted indicated average effective pressure; If the number of consecutive mismatches is less than N, returning to adjusting the amount of gas fuel according to the measured rotational speed of the crankshaft; And determining whether the scavenging pressure supplied to the cylinder is equal to a predicted scavenging pressure when the number of consecutive mismatches is N or more.

According to the present invention, the following effects can be obtained.

The present invention is implemented so that the amount of gas fuel can be quickly supplied to the cylinder by using at least one of the combustion pressure and the scavenging pressure according to the engine load, thereby preventing abnormal combustion such as knocking, premature ignition, misfire This can prevent the engine efficiency from being lowered.

1 is a schematic block diagram of a marine engine according to the present invention;
2 is a schematic flowchart of a ship engine control method according to the present invention;
Figure 3 is a schematic flow chart for explaining the step of determining the number of continuous inconsistency in the ship engine control method according to the present invention

In the present specification, in adding reference numerals to components of each drawing, it should be noted that the same components have the same number as much as possible even though they are displayed on different drawings.

On the other hand, the meaning of the terms described herein will be understood as follows.

Singular expressions should be understood to include plural expressions unless the context clearly indicates otherwise, and the terms “first”, “second”, and the like are intended to distinguish one component from another. The scope of the rights shall not be limited by these terms.

It is to be understood that the term "comprises" or "having" does not preclude the existence or addition of one or more other features or numbers, steps, operations, components, parts or combinations thereof.

The term "at least one" should be understood to include all combinations which can be presented from one or more related items. For example, the meaning of "at least one of the first item, the second item, and the third item" means not only the first item, the second item, or the third item, but also two of the first item, the second item, and the third item, respectively. A combination of all items that can be presented from more than one.

Hereinafter, with reference to the accompanying drawings, a marine engine according to the present invention will be described in detail.

1 to 3, the marine engine 1 according to the present invention has at least one of a combustion pressure generated in a cylinder according to an engine load, and a scavenging pressure of a scavenging receiver for supplying scavenge air to the cylinder. One is to quickly determine the amount of gas fuel and supply it to the cylinder.

To this end, the marine engine 1 according to the present invention includes a cylinder 2, a piston 3, a small receiver 4, a gas supply unit 5, and a control unit 6.

The cylinder 2 is for burning fuel. The piston 3 may be installed to the cylinder 2 to be movable in the vertical direction. The purge receiver 4 is provided below the cylinder 2 and is for supplying air to the cylinder 2. The gas supply part 5 is provided on the side wall of the cylinder 2 to supply gas fuel to the cylinder 2. The control unit 6 is for controlling the gas supply unit 5 to adjust the amount of gas fuel supplied to the cylinder 2. The control unit 6 measures the amount of gas fuel supplied to the cylinder 2 by using at least one of the combustion pressure generated in the cylinder 2 and the scavenging pressure of the purge receiver 4 according to the engine load. You can decide. Therefore, the marine engine 1 according to the present invention is implemented to be able to quickly adjust the amount of gas fuel by using at least one of the combustion pressure and the scavenging pressure in accordance with the engine load to supply to the cylinder 2, knocking, early Abnormal combustion, such as ignition and misfire, can be prevented from occurring, thereby preventing the engine efficiency from being lowered.

Marine engine 1 according to the invention may further comprise an exhaust valve (7). Hereinafter, the cylinder 2, the piston 3, the purge receiver 4, the gas supply unit 5, the control unit 6, and the exhaust valve 7 will be described in detail with reference to the accompanying drawings. Explain.

Referring to FIG. 1, the cylinder 2 is for burning fuel. The cylinder 2 may be formed inside an engine block (not shown). The cylinder 2 has a combustion chamber to which air, fuel, or the like can be supplied. The combustion chamber may be formed in a cylindrical shape with an empty inside. A cylinder liner (not shown) may be installed between the combustion chamber and the engine block. The cylinder 2 may be installed to move the piston (3). For example, the piston 3 may reciprocate in the up and down direction with respect to the Z axis direction (shown in FIG. 1) in the combustion chamber. The Z-axis direction may be a direction parallel to the gravity direction, but may be another direction. The cylinder 2 may be coupled to a gas supply unit 5 for supplying gas fuel. Accordingly, the combustion chamber may receive gas fuel from the gas supply unit 5. The gas supply unit 5 may supply a gas fuel to the combustion chamber after the scavenging air is supplied through the small pores (not shown). The small pores are holes formed through the cylinder 2 at the lower side of the cylinder 2, and may be installed to be connected to the small gas receiver 4 filled with air at a predetermined pressure. Accordingly, the air filled in the small air receiver 4 may be supplied to the combustion chamber when the small air holes are opened. The purge receiver 4 may fill the air at a predetermined pressure by supplying the turbocharger (not shown) by receiving the exhaust gas discharged from the combustion chamber and compressing the air. The combustion chamber may increase or decrease its volume as the piston 3 reciprocates. For example, the cylinder 2 can be reduced in volume when the piston 3 moves upward. In this case, the gaseous fuel and air supplied to the cylinder 2 can be compressed. When the piston 3 moves from the first position P1 (shown in FIG. 1) to reach the second position P2 (shown in FIG. 1), a micropilot injector (not shown) installed above the cylinder 2. By supplying diesel to ignite the compressed gas fuel, a mixed gas of gas fuel and air can be burned and exploded to move the piston 3 downward. The first position P1 is a case where the piston 3 is located at the bottom dead center. The second position P2 is a case where the piston 3 is located at the top dead center. Accordingly, a driving force for rotating the crankshaft CS is generated, and exhaust gas may be generated in the combustion chamber. Accordingly, the load of the engine may be proportional to the combustion pressure of the combustion chamber and the rotational speed of the crankshaft CS (shown in FIG. 1). For example, when the load of the engine is large, the rotation speed of the crankshaft CS is high. If the engine load is small, the rotation speed of the crankshaft CS is slow. Therefore, the ship engine 1 which concerns on this invention can know the load of an engine by measuring the rotational speed of the said crankshaft CS. The cylinder 2 may increase in volume when the piston 3 moves downward. When the piston 3 moves toward the bottom dead center, air filled in the scavenge receiver 4 may be supplied to the combustion chamber. Therefore, the exhaust gas generated by the combustion of the fuel in the combustion chamber may be discharged to the outside of the combustion chamber as air is supplied from the purge receiver 4. In this case, the cylinder 2 may be in an open state by the exhaust valve. The exhaust gas may naturally be discharged to the outside of the combustion chamber due to the high temperature. Exhaust gas may be discharged along an exhaust pipe coupled to the cylinder 2 to be supplied to an exhaust receiver (not shown).

The piston 3 is for compressing air and fuel supplied to the combustion chamber. The piston 3 is installed in the combustion chamber so as to be movable. For example, the piston 3 may reciprocate between the bottom dead center P1 and the top dead center P2 in the combustion chamber. The piston 3 may be formed in a cylindrical shape, but may be formed in another shape as long as it can compress fuel and air while moving in the combustion chamber. The piston 3 can move upward by a crankshaft CS (not shown) that transmits a driving force. The piston 3 may be connected to the crankshaft CS through the rod-shaped piston rod and connecting rod. The piston 3 may move upward as the crankshaft CS rotates. The crankshaft CS may be rotated by a turning gear. The piston 3 can compress fuel and air when it moves upward by the crankshaft CS. The piston 3 can move downward as the fuel and air supplied to the cylinder 2 are exploded by mixing combustion at the top dead center P2. Therefore, the piston 3 can reciprocate between the bottom dead center P1 and the top dead center P2 inside the cylinder 2. The bottom dead center P1 is a point where the piston 3 is located at the lowest position in the cylinder 2 with respect to the Z axis direction. The top dead center P2 is a point where the piston 3 is located at the highest position in the cylinder 2 with respect to the Z axis direction. In the marine engine 1 according to the present invention, when the piston 3 reaches the top dead center P2, the compressed fuel may be exploded to generate a driving force.

The sweeping receiver 4 is for supplying air to the cylinder 2. The purge receiver 4 may receive and store compressed air from the turbocharger. The purge receiver 4 may be connected to the cylinder 2 through a small pore (not shown) installed below the cylinder 2, but is not limited thereto and may be connected to the cylinder 2 through a hose or a pipe. May be connected. The sweeping receiver 4 may supply air to the cylinder 2 when the sweeping pores are opened. When the small pores are closed, the small receiver 4 cannot supply air to the cylinder 2. The small pores may be opened or closed depending on the position of the piston moving in the cylinder (2). The scavenge receiver 4 may store the air at a predetermined pressure because air should be supplied to the cylinder 2 when the scavenge pores are opened. For example, the purge receiver 4 may store air at a pressure of 1 bar to 8 bar. Since the purge receiver 4 receives air from the turbocharger, if the amount of air compressed by the turbocharger 4 is small, the purge receiver 4 stores the air at a low pressure. On the contrary, when the amount of air compressed by the turbocharger is large, the purge receiver 4 stores the air at a high pressure. The turbocharger compresses air using exhaust gas. Accordingly, the scavenge receiver 4 is the pressure of the exhaust gas. That is, the pressure of the stored air may vary according to the load of the engine. Therefore, the scavenging pressure stored by the scavenging receiver 4 is closely related to the load of the engine. For example, if the load on the engine is low. That is, when the speed of the ship is low, the desired pressure supplied to the cylinder 2 is low. On the other hand, if the load on the engine is large. In other words, if the speed of the ship is high, the desired pressure supplied to the cylinder 2 is high. Therefore, the marine engine 1 according to the present invention can know the load of the engine by measuring the scavenging pressure of the scavenging air stored in the scavenging receiver 4.

The gas supply unit 5 is for supplying gas fuel to the cylinder (2). The gas supply part 5 may be provided on the side wall of the cylinder 2. The side wall of the cylinder 2 may be a wall surface that guides the piston 3 to allow the piston 3 to reciprocate in the cylinder 2. The gas supply part 5 may be coupled to the cylinder 2 to be located between the top dead center P2 and the bottom dead center P1 of the piston 3. The gas supply part 5 may supply gas fuel to the cylinder 2 while the piston 3 moves from the bottom dead center P1 to the top dead center P2. The gas supply unit 5 may supply a gas fuel and air to the cylinder 2 while the piston 3 moves from the bottom dead center P1 to the top dead center P2. For example, the gas supply part 5 is added from an auxiliary air supply part (not shown) when the gas is supplied to the cylinder 2 in the middle of the piston 3 moving from the bottom dead center P1 to the top dead center P2. It can be supplied with air. Therefore, since the marine engine 1 according to the present invention can supply gas fuel and air to the cylinder 2 by mixing, the air and gas fuel are mixed more uniformly than when the gas fuel is supplied only to the cylinder 2. This can reduce or prevent the occurrence of abnormal combustion such as knocking and premature ignition. The gas supply part 5 may supply gas fuel to the cylinder 2 after air is supplied to the cylinder 2 through small pores. When the vessel is an LNG carrier, the gas supply unit 5 may vaporize LNG stored in a gas storage tank (not shown) and supply the gas to the cylinder 2. The gas supply unit 5 may supply BOG (Boil off gas) generated in the gas storage tank to the cylinder (2).

The exhaust valve 7 may be movably coupled to the cylinder 2 based on the Y-axis direction. The exhaust valve 7 may be coupled to the cylinder 2 to be located above the cylinder 2. The exhaust valve 7 is for opening and closing the cylinder 2 so that the exhaust gas generated as the fuel and air are combusted is discharged from the cylinder 2. The exhaust valve 7 may be connected to the control unit 6 by at least one of wired communication and wireless communication. Thus, the exhaust valve 7 can be opened and closed by the cylinder 6 by being moved by the control unit 6. For example, the exhaust valve 7 is moved downward by the control part 6, so that the cylinder 2 and the exhaust pipe can communicate. Accordingly, the exhaust valve 7 can open the cylinder 2. In this case, the exhaust gas may be naturally discharged to the outside through the exhaust pipe due to the high temperature, or if the air is supplied to the inside of the cylinder 2, the exhaust gas may be discharged to the outside through the exhaust pipe artificially by the desired pressure. The exhaust valve 7 is moved upward by the control unit 6, thereby blocking the cylinder 2 and the exhaust pipe. Thus, the exhaust valve 7 can close the cylinder 2. When the exhaust valve 7 closes the cylinder 2 and the piston 3 moves toward the top dead center, gas fuel is supplied to the cylinder 2, and when the piston 3 further moves toward the top dead center, the supplied gas fuel and Desiccation may be compressed.

The control unit 6 is for controlling the gas supply unit 5. As the control unit 6 controls the gas supply unit 5, the amount of gas fuel supplied to the cylinder 2 may vary. The control unit 6 may control the gas supply unit 5 by being connected to the gas supply unit 5 by at least one of wireless communication and wired communication. The control unit 6 is a gas fuel supply valve of the exhaust valve 7 and the gas supply unit 5 so that the gas fuel is supplied to the cylinder 2 after the exhaust valve 7 closes the cylinder 2. (Not shown) can be controlled. The control unit 6 uses at least one of a combustion pressure generated when the fuel supplied to the cylinder 2 is combusted according to an engine load, and a desired scavenging pressure stored in the scavenging receiver 4. The amount of gas fuel supplied to 2) can be determined. Accordingly, the marine engine 1 according to the present invention may further include a first measuring unit 8, a second measuring unit 9, and a third measuring unit 10.

The first measuring unit 8 is for measuring the rotational speed of the crankshaft CS. The first measuring unit 3 is installed on the flywheel of the crankshaft CS to measure the rotational speed of the flywheel, thereby measuring the rotational speed of the crankshaft CS. The first measuring unit 8 may be a governor. The first measuring unit 8 may be one, but a plurality of first measuring units 8 may be installed at different positions of the crankshaft CS in order to increase the reliability of the rotation speed value of the crankshaft CS. The first measuring unit 8 may be connected to the control unit 6 by at least one of wireless communication and wired communication. Accordingly, the first measuring unit 8 may provide the controller 6 with information on the rotation speed of the crankshaft CS.

The second measuring unit 9 is for measuring the scavenging pressure of the scavenging air stored in the scavenging receiver 4. The second measuring unit 9 may be installed to span the inside, outside, or outside of the scavenge receiver 4 to measure the scavenge pressure of the scavenge stored in the scavenge receiver 4. The second measuring unit 9 may be a pressure sensor. The second measuring unit 9 may be one, but a plurality of second measuring units 9 may be installed at different positions of the scavenging receiver 4 in order to increase the reliability of the scavenging pressure stored in the scavenging receiver 4. The second measuring unit 9 may be connected to the control unit 6 by at least one of wireless communication and wired communication. Therefore, the second measuring unit 9 may provide the measured pressure scavenging pressure information to the controller 6.

The third measuring unit 10 is for measuring the combustion pressure generated during the combustion of the fuel in the cylinder (2). The third measuring unit 10 is installed in the cylinder cover coupled to the upper side of the cylinder to the inside of the cylinder. That is, the combustion pressure generated when the fuel burns in the combustion chamber can be measured. The third measuring unit 10 may be a pressure sensor. The third measuring unit 10 is a gas fuel is supplied to the cylinder (2) when the piston 3 moves toward the top dead center (P2) after the exhaust valve (7) closes the cylinder (2), As the piston 3 moves further toward the top dead center P2, the combustion pressure generated as the gas fuel and the scavenged gas are compressed and burned can be measured. The third measuring unit 10 may be one, but a plurality of third measuring units 10 may be installed at different positions such as a cylinder cover and a cylinder liner in order to increase the reliability of the combustion pressure. The third measuring unit 10 may be connected to the control unit 6 by at least one of wireless communication and wired communication. Therefore, the third measuring unit 10 may provide the measured combustion pressure information to the controller 6.

The controller 6 receives the corresponding information from the first measuring unit 8, the second measuring unit 9, and the third measuring unit 10, respectively, and supplies the corresponding fuel to the cylinder 2. The amount can be determined. The corresponding information includes a rotation speed value of the crankshaft CS measured by the first measuring unit 8, a scavenging pressure value of the scavenging receiver 4 measured by the second measuring unit 9, and the third It may be a combustion pressure value of the cylinder 2 measured by the measuring unit 10. The controller 6 may determine the amount of gas fuel supplied to the cylinder 2 according to the load of the engine by the following control method. Therefore, the marine engine 1 according to the present invention is implemented to be able to quickly adjust the amount of gas fuel by using at least one of the combustion pressure and the scavenging pressure in accordance with the engine load to supply to the cylinder, knocking, premature ignition, misfire It is possible to prevent the occurrence of abnormal combustion such as to prevent the engine efficiency from being lowered. Here, the engine load can be known from the rotational speed of the crankshaft CS measured by the first measuring unit 8.

The controller 6 receives the combustion pressure information of the cylinder 2 measured plural times from the third measuring unit 10 to calculate the indicated average effective pressure IMP, and the calculated average effective pressure value is When the number of times of inconsistency with the predicted indicated average effective pressure value is equal to or more than N (N is an integer greater than 0), the amount of gas fuel supplied to the cylinder may be determined using the scavenging pressure of the scavenging receiver. For example, N may be 4. Accordingly, the marine engine 1 according to the present invention, if the number of discrepancies is less than four times, judges again whether the calculated indicated average effective pressure value and the predicted indicated average effective pressure value are the same, In the fourth case, the amount of gas fuel supplied to the cylinder may be determined using the scavenging pressure of the scavenging receiver. Accordingly, the marine engine 1 according to the present invention, if the number of times that the calculated mean mean effective pressure value is inconsistent with the predicted mean mean effective pressure value is four or more times in a row, the scavenging pressure value of the scavenge receiver 4 is determined. Since the amount of gas fuel supplied to the cylinder 2 can be determined, it is possible to prevent the process of determining whether the calculated indicated average effective pressure value is equal to the predicted indicated average effective pressure value indefinitely. The fuel supply amount supplied to the cylinder 2 can be quickly determined. Although not shown, the controller 6 may notify an operator such as a navigator without re-determining whether the calculated instructed mean effective pressure value is equal to the predicted instructed mean effective pressure value when the number of mismatches is five. . For example, if the number of inconsistencies is five, the controller 5 stops the determination of the same and displays an error occurrence in determining the fuel supply amount supplied to the cylinder 2 through a display device or alarms through an alarm device. By ringing it can inform the operator of the occurrence of the error.

Hereinafter, a ship engine control method according to the present invention will be described in detail with reference to the accompanying drawings.

2 is a schematic flowchart of a marine engine control method according to the present invention, Figure 3 is a schematic flowchart for explaining the step of determining the number of continuous inconsistency in the marine engine control method according to the present invention.

1 to 3, the marine engine control method according to the present invention may be performed by the marine engine 1 according to the present invention described above. Marine engine control method according to the present invention includes the following configuration.

First, the rotation speed of the crankshaft CS is measured (S100). This step (S100) may be made by the first measuring unit 8 measures the rotational speed of the crankshaft (CS) flywheel. The first measuring unit 8 may provide the controller 6 with the measured rotation speed information of the crankshaft CS by at least one of wireless communication and wired communication.

Next, fuel is added or subtracted and injected into the cylinder 2, and the mixture of fuel and air injected into the cylinder 2 is compressed (S200). This step (S200) is supplied by adjusting the amount of fuel supplied to the cylinder 2 by the gas supply unit 5 under the control of the control unit 6, the piston 3 is moved upwards and injected with By compressing air. The controller 6 may determine the amount of fuel supplied by the gas supply unit 5 to the cylinder 2 according to the load of the engine through the steps to be described later.

Next, the combustion pressure of the cylinder 2 is measured (S300). This step (S300) may be performed by the third measuring unit 10 measuring the pressure when the fuel and air injected into the cylinder 2 are compressed and combusted. The third measuring unit 10 may provide the measured combustion pressure information to the controller 6 by at least one of wireless communication and wired communication.

Next, the indicated average effective pressure (IMEP) is calculated (S400). This step (S400) may be derived from the combustion pressure information of the cylinder 2 provided by the control unit 6 from the third measuring unit 10. The third measuring unit 10 may measure the combustion pressure in one cylinder 2 a plurality of times and provide the same to the controller 6. The controller 6 may calculate the indicated average effective pressure IMP by averaging the combustion pressures provided from the third measuring unit 10.

Next, it is determined whether the calculated instructed mean effective pressure value is within a predetermined reference indication average effective pressure range (S500). This step (S500) may be made by the controller (6). The reference indicated average effective pressure range is an indicated average effective pressure range in which abnormal combustion such as knocking, premature ignition, misfire or the like does not occur or is minimized, and has a minimum indicated average effective pressure value and a maximum indicated average effective pressure value. The reference indication average effective pressure range may be preset by the operator.

Next, if the calculated indicated average effective pressure value is within the predetermined reference average effective pressure range, it is determined whether the calculated indicated average effective pressure value is equal to the predicted indicated average effective pressure value (S600). This step S600 may be performed by the controller 6. The predicted indication average effective pressure value may be preset by the operator as a value derived during an initial engine test.

Next, if the calculated indicated average effective pressure value is equal to the predicted indicated average effective pressure value, the amount of fuel supplied to the cylinder 2 is determined (S700). This step (S700) may be made by the controller (6). When the amount of fuel supplied to the cylinder 2 is determined, the controller 6 may control the gas supply unit 5 to supply fuel to the cylinder 2 in the determined amount. Therefore, the marine engine control method according to the present invention can adjust the amount of fuel supplied to the cylinder (2) by using the rotational speed of the crankshaft (CS) and the combustion pressure of the cylinder (2), knocking, It is possible to prevent or reduce the efficiency of the engine by reducing or preventing occurrence of abnormal combustion such as premature ignition and misfire.

Next, if the calculated indicating average effective pressure value is not the same as the predicted indicating average effective pressure value (S600), the gas supply unit 5 returns to the step of injecting fuel into the cylinder 2 (S200) and the step ( S300, S400, S500) is performed again.

Next, in the step S500 of determining whether the calculated instructed mean effective pressure value is within a preset reference indication average effective pressure range, if the calculated instructed mean effective pressure value does not fall within the preset reference mean effective pressure range, It is determined whether the scavenging pressure value of 4) is equal to the expected scavenging pressure value (S510). The step S510 may be performed by the controller 6 determining whether the scavenging pressure value of the scavenging receiver 4 provided from the second measuring unit 9 is equal to the expected scavenging pressure value. The predicted scavenging pressure value may be preset by the operator as the scavenging pressure value of the scavenging receiver 4 derived during the initial engine test. This step (S510) may be performed when the third measuring unit 10 is damaged or broken, so that the combustion pressure of the cylinder 2 cannot be measured or an error occurs in the calculated average measured effective pressure value.

Next, when the scavenging pressure value of the scavenging receiver 4 is equal to the expected scavenging pressure value (S510), the amount of fuel supplied to the cylinder 2 is determined (S700). This step S700 is the same as described above.

Next, when the scavenging pressure value of the scavenging receiver 4 is not the same as the expected scavenging pressure value (S510), the gas supply unit 5 returns to the step of injecting fuel into the cylinder 2 (S200) and the step ( S300, S400, S500) is performed again.

In the ship engine control method according to the present invention, when the third measuring unit 10 is damaged or broken, the rotation speed value of the crankshaft CS and the second measuring unit measured by the first measuring unit 8 are measured. The amount of fuel supplied to the cylinder 2 can be determined using the scavenging pressure value of the scavenging receiver 4 measured by (9). That is, in the ship engine control method according to the present invention, the combustion pressure measured by the third measuring unit 10 and the scavenging pressure measured by the second measuring unit 9 may be used as a backup concept. Accordingly, the marine engine control method according to the present invention determines the amount of fuel supplied to the cylinder 2 by using at least one of the combustion pressure of the cylinder 2 and the scavenging pressure of the scavenging receiver 4 according to the engine load. Since it can be supplied to the cylinder 2 quickly, abnormal combustion such as knocking, premature ignition, misfire, etc. can be prevented from occurring, and the engine efficiency is improved by preventing the air-fuel ratio, which is a mixture ratio of air and fuel, from being lowered or increased. You can.

Referring to FIG. 3, in the marine engine control method according to the present invention, if the calculated average command effective pressure value is not the same as the predicted command average effective pressure value (S600), the number of times that are not the same continuously, that is, the number of consecutive inconsistencies. And determining whether or not is less than N times (N is an integer greater than 0). For example, N may be 4. The step 610 may be performed before the step S510 of determining whether the scavenging pressure value of the scavenging receiver 4 is equal to the expected scavenging pressure value. The step S610 may be performed by the controller 6. If the number of consecutive mismatches is less than four, the gas supply unit 5 returns to the step of injecting fuel into the cylinder 2 (S200) and re-performs the steps S300, S400, and S500. When the number of consecutive mismatches is four or more times, a step (S510) is performed to determine whether a scavenging pressure value of the scavenging receiver 4 is equal to a predicted scavenging pressure value. This process may be forced by an operator or in accordance with a preset control logic. Therefore, the marine engine control method according to the present invention uses the scavenging pressure value of the scavenging receiver 4 when the number of times that the calculated average mean effective pressure value is inconsistent with the predicted average mean effective pressure value is four or more times in a row. Since the amount of gas fuel supplied to the cylinder 2 can be determined, the process of determining whether or not the calculated indicated average effective pressure value is equal to the predicted indicated average effective pressure value is prevented from being repeated indefinitely. The amount of fuel supplied to the cylinder 2 can be quickly determined.

The present invention described above is not limited to the above-described embodiment and the accompanying drawings, and it is common in the art that various substitutions, modifications, and changes can be made without departing from the technical spirit of the present invention. It will be apparent to those who have the knowledge of.

1: Marine Engine
2: cylinder 3: piston
4: gas receiver 5: gas supply unit
6: exhaust valve 7: control unit
8: first measuring unit 9: second measuring unit
10: third measuring unit

Claims (7)

A cylinder for burning fuel;
A piston installed in the cylinder so as to be movable upward and downward;
A small receiver installed at a lower side of the cylinder to supply air to the cylinder;
A gas supply part provided on a side wall of the cylinder to supply gas fuel to the cylinder;
A control unit for controlling the gas supply unit to adjust the amount of gas fuel supplied to the cylinder,
The control unit is a marine engine, characterized in that for determining the amount of gas fuel supplied to the cylinder by using at least one of the combustion pressure generated in the cylinder, and the scavenging pressure of the scavenge receiver in accordance with the engine load. The method of claim 1,
A third measuring unit for measuring a combustion pressure of the cylinder,
The controller calculates an indication average effective pressure (IMEP) by receiving combustion pressure information of the cylinder measured plural times from the third measuring unit, and the calculated average effective pressure value is inconsistent with the predicted average effective pressure value. If the number of times consecutively N (N is an integer greater than 0) or more times, the engine for ship, characterized in that for determining the amount of gas fuel supplied to the cylinder using the scavenging pressure of the scavenging receiver. The method of claim 1,
A first measuring unit for measuring the rotational speed of the crankshaft of the engine;
A second measuring unit for measuring the scavenging pressure stored in the scavenging receiver; And
A third measuring unit for measuring a combustion pressure of the cylinder,
The control unit is a marine engine, characterized in that for receiving the corresponding information from the first measuring unit, the second measuring unit and the third measuring unit to determine the amount of gas fuel supplied to the cylinder. The method of claim 2,
And an exhaust valve for discharging the exhaust gas generated from the gas fuel and air in the cylinder by compression combustion.
And the third measuring unit measures a combustion pressure generated when fuel is combusted after the exhaust valve closes the cylinder. Measuring the rotational speed of the crankshaft;
Adjusting the amount of gas fuel according to the measured rotational speed of the crankshaft to supply the cylinder, and compressing and burning the mixture of gas fuel and air supplied to the cylinder;
Measuring a combustion pressure of the mixture combusted in the cylinder;
Calculating an indicated average effective pressure from the combustion pressure;
Determining whether the calculated average indicated effective pressure falls within a preset reference average effective pressure range;
Determining whether the scavenging pressure supplied to the cylinder is equal to a predicted scavenging pressure when the calculated indicated average effective pressure value is out of a predetermined reference indicator average effective pressure range;
Determining an amount of gas fuel supplied to the cylinder when the scavenging pressure supplied to the cylinder is equal to a predicted scavenging pressure; And
And returning to the step of adjusting the amount of gas fuel according to the measured rotation speed of the crankshaft if the scavenging pressure supplied to the cylinder is different from the expected scavenging pressure. The method of claim 5,
Determining whether the calculated indicated average effective pressure is equal to a predicted indicated average effective pressure if the calculated indicated average effective pressure belongs to a preset reference indicated average effective pressure range;
Determining the amount of gas fuel supplied to the cylinder when the calculated indicated average effective pressure is equal to the predicted indicated average effective pressure; And
And returning to the step of adjusting the amount of gas fuel according to the measured rotation speed of the crankshaft if the calculated indicating average effective pressure is different from the predicted indicating average effective pressure. The method of claim 6,
Determining whether the number of consecutive mismatches is less than N (N is an integer greater than 0) if the calculated indicated average effective pressure is not equal to the predicted indicated average effective pressure;
If the number of consecutive mismatches is less than N, returning to adjusting the amount of gas fuel according to the measured rotational speed of the crankshaft; And
And determining whether the scavenging pressure supplied to the cylinder is equal to a predicted scavenging pressure when the number of consecutive mismatches is N or more.

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