KR102684155B1 - Large low speed turbocharged two-stroke uniflow scavenged internal combustion engine with crossheads and method of operating of such engine - Google Patents

Abstract

An exhaust valve (4), an exhaust valve actuating system (46) for operating the exhaust valve (4), a fuel delivery system (30) for delivering a quantity of first fuel to the associated cylinder (1), an associated cylinder (1) A large low-speed two-stroke internal combustion engine ( One). The method provides closed-loop control of fuel quantity, fuel intake/injection initiation, individually according to the cylinder-specific pressure signal and according to the common setpoint for all cylinders, or according to the individual cylinder-specific setpoint, which is an individual cylinder-specific adjustment of the common setpoint. Timing and/or exhaust valve closing timing. Another method is to control combustion process parameters individually on a cylinder-by-cylinder basis as a function of the operating conditions of the engine by periodically adjusting a common setpoint for the combustion process parameter(s) on a cylinder-by-cylinder basis, calculating an average of the cylinder-by-cylinder adjustments. determining a window around the calculated mean and limiting cylinder-specific adjustments in a cycle of combustion process parameters to a predetermined maximum deviation range from the calculated mean of the relevant combustion process parameter.

Description

LARGE LOW SPEED TURBOCHARGED TWO-STROKE UNIFLOW SCAVENGED INTERNAL COMBUSTION ENGINE WITH CROSSHEADS AND METHOD OF OPERATING OF SUCH ENGINE}

The present disclosure relates to a large, low-speed, turbocharged, two-stroke, uniflow scavenging internal combustion engine having a crosshead and a plurality of cylinders and a method of operating such an internal combustion engine.

Large, low-speed, turbocharged, two-stroke, single-flow scavenging internal combustion engines with crossheads are commonly used as propulsion systems for large ships or as prime movers in power plants.

Modern engines of this type are completely electronically controlled. That is, the opening and closing of fuel inlet/injection and exhaust valves can be adjusted by the electronic control system during engine operation, ensuring that the engine operates optimally under given operating conditions.

Engines are calibrated at the factory to ensure they meet all performance requirements such as power, fuel economy, emissions, noise/vibration levels and reliability.

Therefore, when it leaves the factory, the engine operates optimally and meets performance requirements. However, over time, the engine, or at least its cylinders, deviate from factory specifications and require recalibration.

There is a recent need for large turbocharged two-stroke compression ignition engines that can handle alternative fuel types such as natural gas, petroleum gas, methanol, coal slurry, water-oil mixtures, petroleum coke, etc.

Some of these alternative fuels have the potential to reduce costs and emissions.

Large, low-speed, single-flow, scavenging, turbocharged two-stroke internal combustion engines are generally used to propulsion large ocean-going cargo ships, so reliability is of utmost importance. The operation of these engines with alternative fuels continues to be developed relatively recently, and the redundancy of operation with gaseous fuels leads to a lower level of reliability than when operating with conventional fuels. The operating time of a dual-fuel engine is by design less when running on gaseous fuel to reduce costs. For example, gaseous fuel systems have less redundancy. If a failure is detected in one cylinder, gaseous fuel supply to all cylinders is stopped. In conventional fuel (fuel oil) mode, only the cylinder affected by the failure is stopped. Operating on conventional fuel ensures reliability. Therefore, it is important to be able to quickly switch from alternative to conventional fuels because operating on conventional fuels is considered a safe dependency.

Therefore, all existing large, low-speed two-stroke diesel engines are dual-fuel engines with systems that run on alternative fuels. For example, with a fuel system that runs on conventional fuel, such as fuel oil, and a gaseous fuel system, the engine can run at full power with conventional fuel only.

If there are problems operating with alternative fuels, for example, insufficient gas pressure when operating on gaseous fuels, it must be possible to immediately switch from alternative fuel operation to conventional fuel operation. It is also important to be able to switch back from conventional fuels to alternative fuels quickly and easily to save costs and reduce emissions.

However, when the fuel type is changed, the combustion process is no longer the same and the engine must be recalibrated to run on a different fuel. For example, fuel injection timing and duration, exhaust valve closing timing, scavenging pressure, compression pressure, cylinder peak pressure, and average indicated pressure control must be adjusted to the type of fuel used. This means that new process balances must be achieved, especially since the properties (heating value) of the gaseous fuel delivered by typical gaseous fuel systems can exhibit large variations.

Known engine control systems are unable to perform this recalibration in a satisfactory manner without human intervention. Known control systems either take too long or are not accurate enough to achieve optimal operating conditions for the engine immediately after fuel switching.

Additionally, large, low-speed, turbocharged, two-stroke, single-flow scavenging internal combustion engines are factory calibrated to ensure that the combustion process in each cylinder of the engine performs according to design criteria for the entire operating conditions of the engine. At the factory the cylinders are balanced (load balanced). That is, the highest cylinder values (peaks) or the average indicated pressures (loads) of individual cylinders are made as even as possible. Alternatively, instead of peak pressure, the average indicated pressure is maintained as evenly as possible for each cylinder to ensure the best load balance.

However, over time after leaving the factory, wear affects the engine and each cylinder differently. During use, the cylinder's combustion process deviates from factory specifications, causing cylinder balance to deteriorate. This evolution will lead to reduced performance and increased emissions over time, which must be countered at some point by recalibration of the control system.

Known control systems for large two-stroke internal combustion engines require human intervention for this recalibration. However, since one of the parameters changes (e.g. the closing angle of the exhaust valve affects the range of other parameters), manual intervention requires specialized skills. Typically, engine operations personnel do not have the necessary skills to perform recalibrations involving human intervention, and for this reason, such recalibrations do not occur in practice. Some of the consequences of this lack of recalibration are increased fuel consumption and emissions.

<Rolle S., Wiesmann A. Combustion Control and Monitoring of two-stroke engines, W rtsil Technical Journal, 2011> describes an engine with a closed-loop fuel control system in which a common load setpoint is provided for all cylinders, cylinder pressure is measured individually for each cylinder, and fuel injection timing and exhaust valve closure are adjusted accordingly. It is starting.

Patent Document 1: Republic of Korea Patent Application No. 10-2012-7015139

Against this background, the object of the present application is to provide a large, low-speed, turbocharged, two-stroke, single-flow scavenging internal combustion engine and a method of operating such an internal combustion engine, which overcomes or at least reduces the above-mentioned problems.

The above object is achieved according to a first aspect by providing a large, low-speed, two-stroke, single-flow, scavenging, turbocharged internal combustion engine with a crosshead, the internal combustion engine comprising:

A plurality of cylinders comprising:

- exhaust valve,

- an exhaust valve actuating system for operating the exhaust valve,

- a fuel delivery system for delivering a quantity of primary fuel to the relevant cylinders,

- Pressure sensor to generate a cylinder-specific pressure signal indicating the pressure of the relevant cylinder

an exhaust gas driven turbocharger to pressurize the scavenging air in the cylinder; and

A controller configured to receive or determine:

A common torque signal representing the torque delivered by the engine,

A common peak pressure signal representing the peak cylinder pressure to be realized in the cylinder,

A common compression pressure signal indicating the compression pressure to be realized in the cylinder.

The controller receives pressure signals for each cylinder,

a) The controller derives from the cylinder-specific pressure signal an actual cylinder-specific torque signal representing the torque delivered by the specific cylinder concerned, and as a function of the deviation of the common torque signal from the actual cylinder-specific torque signal to obtain the cylinder-specific torque signal. configured to adjust the common torque signal, and configured to deliver a certain amount of fuel to the relevant specific cylinder as a function of the cylinder-specific torque signal, and

b) The controller derives an actual cylinder-specific peak pressure signal representing the peak pressure of the relevant cylinder (1) from the cylinder-specific pressure signal, and calculates the common peak pressure signal from the actual cylinder-specific peak pressure signal to obtain the cylinder-specific peak pressure signal. adjusting the common peak pressure signal as a function of the deviation of

configured to measure the start time of delivery of said quantity of fuel to the specific cylinder (1) concerned as a function of the cylinder-specific peak pressure signal, and

c) The controller derives an actual cylinder-specific peak pressure signal representing the peak pressure of the relevant cylinder (1) from the cylinder-specific pressure signal, and calculates the common peak pressure signal from the actual cylinder-specific peak pressure signal to obtain the cylinder-specific peak pressure signal. adjusting the common peak pressure signal as a function of the deviation of

It is configured to measure the closing time of the exhaust valve of the specific cylinder concerned as a function of the cylinder-specific compression pressure signal.

By adjusting the cylinder-specific combustion process parameter(s), i.e. by generating a cylinder-specific torque signal, cylinder-specific supply pressure signal and/or cylinder-specific compression pressure signal in a feedback loop, each cylinder can Even if the operating conditions of the cylinder are changed, operation exactly according to factory specifications can be achieved. At the same time, it is achieved that the control of the combustion process in the engine cylinders is carried out without taking into account the cylinder or load balance of the entire engine cylinder. This engine control method ensures that each cylinder operates optimally without having to worry about cylinder balance (load balance).

In a possible embodiment of the first aspect, the internal combustion engine is fuel driven and includes at least element a).

In a possible embodiment of the first aspect, the internal combustion engine is air-driven and comprises at least element c).

In a possible embodiment of the first aspect, the internal combustion engine is partly fuel-driven and partly air-driven and includes at least elements a) and element c).

In a possible embodiment of the first aspect,

The internal combustion engine is a dual fuel engine and the fuel delivery system is configured to handle at least two different fuels, each cylinder having at least one fuel valve for delivering the first fuel and at least one fuel valve for delivering the second fuel. is provided.

In a possible embodiment of the first aspect,

Internal combustion engines are fuel-driven when running on a primary fuel and air-driven when running on a secondary fuel.

In a possible embodiment of the first aspect,

The controller receives the desired engine speed and receives the measured engine speed, and the controller includes a governor configured to determine a fuel index signal as a function of the deviation of the desired engine speed from the measured engine speed.

In a possible embodiment of the first aspect,

The controller is configured to convert the fuel index signal to a common torque signal by applying the fuel index signal to a first predetermined map.

In a possible embodiment of the first aspect,

The controller includes a power calculation module configured to calculate an engine load signal representative of the engine load, and the power calculation module preferably receives a fuel index signal and a measured engine speed.

In a possible embodiment of the first aspect,

The controller is configured to determine a common peak pressure signal by applying the engine load signal to a second predetermined map, and/or to determine a common compressed pressure signal by applying the engine load signal to a third predetermined map.

In a possible embodiment of the first aspect,

The controller includes a fuel index signal to profile duration module, wherein the profile duration module is configured to convert the fuel index signal to a common fuel delivery duration signal.

In a possible embodiment of the first aspect,

The controller is configured to adjust the common fuel delivery duration signal as a function of the deviation of the common fuel delivery duration signal from the cylinder-specific torque signal to obtain a cylinder-specific fuel delivery duration signal.

In a possible embodiment of the first aspect,

The controller is configured to determine a cylinder-specific injection profile as a function of a cylinder-specific torque signal or as a function of a cylinder-specific fuel delivery duration signal, and the fuel delivery system is configured to open one or more fuel valves according to the cylinder-specific injection profile to open the relevant specific cylinder. Deliver the amount of fuel to.

In a possible embodiment of the first aspect,

The fuel delivery system initiates delivery of the fuel quantity to the specific cylinder concerned by opening one or more fuel valves in accordance with the start of the fuel quantity delivery timing determined by the controller.

In a possible embodiment of the first aspect,

The controller 55 is configured to limit the magnitude of the adjustment of the common torque signal to a first threshold when the adjustment for the other cylinder 1 is in the same direction, and the controller 55 is configured to limit the magnitude of the adjustment for the other cylinder 1 to a first threshold. configured to limit the magnitude of the adjustment of the common torque signal to a second threshold when the adjustment is in the opposite direction;

and/or

The controller 55 is configured to limit the magnitude of the adjustment of the common peak pressure signal to a first threshold when the adjustment for the other cylinder 1 is in the same direction, and the controller 55 is configured to limit the magnitude of the adjustment for the other cylinder 1 to a first threshold. configured to limit the magnitude of the adjustment of the common peak pressure signal to a second threshold when the adjustment is in the opposite direction;

and/or

The controller 55 is configured to limit the magnitude of the adjustment of the common peak pressure signal to a first threshold when the adjustment for the other cylinder 1 is in the same direction, and the controller 55 is configured to limit the magnitude of the adjustment for the other cylinder 1 to a first threshold. and configured to limit the magnitude of the adjustment of the common peak pressure signal to a second threshold when the adjustment is in the opposite direction.

In a possible embodiment of the first aspect,

The second threshold is lower than the first threshold.

In a possible embodiment of the first aspect,

The first, second and/or third predetermined maps are preferably predetermined at the engine shop from tests of the relevant engine or the same or similar engines, and the first, second and/or third predetermined maps are Preferably includes algorithms and/or tables.

In a possible embodiment of the first aspect,

The common torque signal corresponds to the average indicated cylinder pressure for all cylinders, and the cylinder-specific torque signal corresponds to the average indicated cylinder pressure for the specific cylinder involved.

In a possible embodiment of the first aspect,

The controller includes a cylinder-specific cylinder offset module for each cylinder, wherein the cylinder-specific offset module is configured to offset a common torque signal, a common peak pressure signal, and/or a common compression pressure signal for the specific cylinder involved.

In a possible embodiment of the first aspect,

The cylinder-specific offset module is controlled manually or automatically.

In a possible embodiment of the first aspect,

The controller is configured to individually control the engine's cylinders without considering cylinder balance.

In a possible embodiment of the first aspect,

The controller is configured to continuously calculate the error value as the difference between the torque for each cylinder and the actual torque for each cylinder when the internal combustion engine has element a) and apply correction based on the proportional term and integral term. ), the error value is continuously calculated as the difference between the peak pressure for each cylinder and the actual peak pressure for each cylinder, and the controller is configured to apply correction based on the proportional term and integral term, and the controller is configured to calculate the error value based on the proportional term and integral term. It is configured to continuously calculate the error value as the difference between the peak pressure for each cylinder and the actual peak pressure for each cylinder and apply correction based on the proportional term and integral term.

In a possible embodiment of the first aspect,

The fuel delivery system is configured to deliver a quantity of the first fuel quantity and/or the secondary fuel quantity to the associated cylinder.

According to a second aspect, a method of operating a large, low-speed, two-stroke, single-flow, scavenging, turbocharged internal combustion engine with a crosshead is provided, comprising:

The internal combustion engine is,

A plurality of cylinders having: and

- exhaust valve,

- an exhaust valve actuating system for operating the exhaust valve,

- a fuel delivery system for delivering a quantity of primary fuel to the relevant cylinders,

- Pressure sensor to generate a cylinder-specific pressure signal indicating the pressure of the relevant cylinder

It includes an exhaust gas driven turbocharger for pressurizing the scavenging air in the cylinder,

The method is:

It includes a per-cylinder pressure signal that is a per-cylinder offset of a common setpoint for all cylinders and a closed loop for controlling on a per-cylinder basis at least one combustion process parameter of the cylinder as a function of the per-cylinder setpoint.

By adjusting each combustion process parameter(s) on a cylinder-by-cylinder basis, i.e., by generating a cylinder-specific torque signal, cylinder-specific supply pressure signal, and/or cylinder-specific compression pressure signal in a feedback loop, each cylinder is subject to engine wear or other factors. Exact operation according to factory specifications can be achieved even if the operating conditions of the relevant cylinders are changed. At the same time, it is achieved that the control of the combustion process in the engine cylinders is carried out without taking into account the cylinder or load balance of the entire engine cylinder. This engine control method ensures that each cylinder operates optimally without having to worry about cylinder balance (load balance).

In a possible embodiment of the second aspect, the at least one combustion process parameter includes:

- fuel quantity,

- fuel injection start timing and/or

- Exhaust valve closing timing.

In a possible embodiment of the second aspect,

Closed loop control is performed without any consideration to maintain cylinder balance.

In a possible embodiment of the second aspect,

Closed-loop control applies corrections based on proportional and integral terms.

In a possible embodiment of the second aspect, the common setpoint is:

A common torque signal representing the torque delivered by the engine, and/or a common peak pressure signal representing the peak cylinder pressure to be realized in the cylinder, and/or a common compression pressure signal representing the compression pressure to be realized in the cylinder.

In a possible embodiment of the second aspect,

Closed-loop control uses the cylinder pressure measured for each cylinder as a reference value.

In a possible embodiment of the second aspect,

The average indicated cylinder pressure per cylinder is derived from the measured cylinder pressure per cylinder, and/or the peak pressure per cylinder is derived from the cylinder pressure measured per cylinder, and/or the compression pressure per cylinder is derived from the measured pressure per cylinder. do.

According to the third aspect,

A method of operating a large, low-speed, two-stroke, single-flow, scavenging, turbocharged internal combustion engine with a crosshead is provided, the internal combustion engine comprising:

A plurality of cylinders having:

- exhaust valve,

- an exhaust valve actuating system for operating the exhaust valve,

- a fuel delivery system for delivering a quantity of primary fuel to the relevant cylinders,

- Pressure sensor to generate a cylinder-specific pressure signal indicating the pressure of the relevant cylinder

an exhaust gas driven turbocharger to pressurize the scavenging air in the cylinder; and

A controller configured to receive or determine the actual operating conditions of the internal combustion engine:

A common torque signal representing the torque delivered by the engine,

A common peak pressure signal representing the peak cylinder pressure to be realized in the cylinder,

A common compression pressure signal indicating the compression pressure to be realized in the cylinder.

The method includes:

a) The controller derives an actual cylinder-specific torque signal representing the torque delivered by the relevant specific cylinder from the cylinder-specific pressure signal and calculates the deviation of the common torque signal from the actual cylinder-specific torque signal to obtain the cylinder-specific torque signal. adjusting the common torque signal as a function, and

Delivering a certain amount of fuel to the specific cylinder involved as a function of the cylinder-specific torque signal.

and/or

b) Deriving an actual cylinder-specific peak pressure signal representing the peak pressure of the relevant cylinder from the cylinder-specific pressure signal, as a function of the deviation of the common peak pressure signal from the actual cylinder-specific peak pressure signal to obtain the cylinder-specific peak pressure signal. adjusting the common peak pressure signal, and

Measuring the timing of the start of delivery of the fuel quantity to the specific cylinder concerned as a function of the cylinder-specific peak pressure signal.

and/or

c) Deriving an actual cylinder-specific compression pressure signal representing the compression pressure of the relevant cylinder from the cylinder-specific pressure signal, a function of the deviation of the common compression pressure signal from the actual cylinder-specific compression pressure signal to obtain the cylinder-specific compression pressure signal. adjusting a common compressed pressure signal as, and

Measuring the closing timing of the exhaust valve as a function of the cylinder-specific compression pressure signal.

According to the fourth aspect,

A large, low-speed, two-stroke, single-flow, scavenging, turbocharged internal combustion engine with a crosshead is provided, the internal combustion engine comprising:

A plurality of cylinders having:

- exhaust valve,

- an exhaust valve actuating system for operating the exhaust valve,

- a fuel delivery system for delivering a quantity of primary fuel to the relevant cylinders,

- Pressure sensor to generate a cylinder-specific pressure signal indicating the pressure of the relevant cylinder

an exhaust gas driven turbocharger to pressurize the scavenging air in the cylinder; and

A controller configured for closed loop that controls one or more combustion process parameters on a cylinder-by-cylinder basis as a function of:

o Cylinder-specific pressure signal, and

o Common setpoint for all cylinders, or

o Cylinder-specific setpoint, which is a cylinder-specific offset from the common setpoint.

According to the fifth aspect,

A large, low-speed, two-stroke, single-flow, scavenging, turbocharged internal combustion engine with a crosshead is provided, the internal combustion engine comprising:

A plurality of cylinders having:

exhaust valve,

an exhaust valve actuating system for operating the exhaust valve;

a fuel delivery system (30) for delivering a quantity of first fuel to the associated cylinders;

an exhaust gas driven turbocharger to pressurize the scavenging air in the cylinder; and

A controller configured to control on a cylinder-by-cylinder basis at least one of combustion process parameter(s), fuel quantity, fuel injection start timing, and exhaust valve closing timing.

The controller 55,

individually controlling the combustion process parameter(s) of a cylinder (1) as a function of the operating conditions of the engine by periodically adjusting common or cylinder-specific setpoints for the combustion process parameter(s) on a cylinder-by-cylinder basis;

Calculate averages across cylinders of cylinder-specific adjustments of combustion process parameter(s),

and is configured to limit cylinder-specific adjustments in a cycle of combustion process parameter(s) to a predetermined maximum deviation range from the calculated average of the relevant combustion process parameter adjustments.

By providing a limiter function that ensures that specific cylinder-specific adjustments remain within limits, it provides enough flexibility to accommodate the large adjustments that occur under normal circumstances while suppressing extremely large adjustments that occur due to errors, thereby avoiding damage or downtime. It can be prevented.

In a possible embodiment of the fifth aspect,

The controller is configured to define a window as a predetermined maximum deviation plus or minus a calculated average of the relevant combustion process parameter adjustments and to limit cylinder-specific adjustments in a cycle of the combustion process parameter(s) to adjustments within the window.

In a possible embodiment of the fifth aspect,

The window is a range having a first range in the plus direction and a second range in the minus direction from the calculated average of the relevant combustion process parameter adjustments.

In a possible embodiment of the fifth aspect,

The window depends on combustion process parameters.

In a possible embodiment of the fifth aspect,

The positive range has a first predetermined size and the negative range has a second predetermined size, and the first predetermined size is not necessarily equal to the second predetermined size.

In a possible embodiment of the fifth aspect,

The controller is configured to calculate an average of cylinder-by-cylinder adjustments to the combustion process parameter(s) over one or multiple cycles of periodic adjustment of the relevant combustion process parameter.

In a possible embodiment of the fifth aspect,

Adjustment of the combustion process parameter(s) is an adjustment for a single cycle.

In a possible embodiment of the fifth aspect,

At least one combustion process parameter includes:

- fuel quantity,

- the fuel injection start timing, and/or

- Exhaust valve closing timing.

In a possible embodiment of the fifth aspect,

The cylinder-specific setpoint for the combustion process parameter(s) is an offset from the common setpoint for the combustion process parameter(s).

In a possible embodiment of the fifth aspect,

The operating conditions of the engine are one or more of the following: engine speed, engine load, cylinder peak pressure, cylinder combustion pressure, cylinder average indicated pressure, scavenge pressure fuel type, ambient humidity, and ambient temperature.

According to the sixth aspect,

A method of operating a large, low-speed, two-stroke, single-flow, scavenging, turbocharged internal combustion engine with a crosshead is provided, the internal combustion engine comprising:

A plurality of cylinders having: and

exhaust valve,

an exhaust valve actuating system for operating the exhaust valve;

a fuel delivery system for delivering a quantity of first fuel to the associated cylinders;

Exhaust gas driven turbocharger to pressurize the scavenging air in the cylinder.

The method includes:

Controlling at least one of combustion process parameter(s), fuel amount, fuel injection start timing, and exhaust valve closing timing on a cylinder-by-cylinder basis;

individually controlling the combustion process parameter(s) of cylinder (1) as a function of the operating conditions of the engine by periodically adjusting common or cylinder-specific setpoints for the combustion process parameter(s) on a cylinder-by-cylinder basis;

calculating an average of the cylinder-specific adjustments to the combustion process parameter(s);

determining a window around the calculated mean of combustion process parameter(s) adjustment; and

Limiting cylinder-specific adjustments in a cycle of combustion process parameter(s) to a predetermined range of maximum deviation from the calculated average of the relevant combustion process parameter adjustments.

Additional objects, features, advantages and characteristics of the fuel valve and engine according to the present disclosure will become apparent from the detailed description.

As described above, according to the present invention, there is an advantage of high accuracy in achieving optimal operating conditions for the engine after fuel switching.

1 is a front view of a large two-stroke diesel engine according to an exemplary embodiment.
Figure 2 is a side view of the large two-stroke engine of Figure 1.
Figure 3 is a schematic representation of the large two-stroke engine according to Figure 1;
Figure 4 is a schematic diagram of one embodiment of a controller for the engine of Figure 1;
Figure 5 is a schematic diagram of another embodiment of a controller for the engine of Figure 1;
Figure 6 is a schematic diagram of another embodiment of a controller for the engine of Figure 1;

In the following detailed description, compression ignition internal combustion engines will be described with reference to a large two-stroke low speed turbocharged internal combustion (diesel) engine in an exemplary embodiment. 1, 2 and 3 show a large, low-speed turbocharged two-stroke compression ignition engine with a crankshaft (8) and a crosshead (9). Figure 3 shows a schematic diagram of a large, low-speed turbocharged two-stroke diesel engine with intake and exhaust systems. In this exemplary embodiment, the engine has six cylinders 1 in a row. Large, low-speed turbocharged two-stroke diesel engines typically have four to fourteen cylinders in a row, supported by an engine frame (11). This engine can be used, for example, as a stationary engine to operate the main engine of an ocean-going ship or a generator in a power plant. The total output of this engine may range, for example, from 1,000 to 110,000 kW.

The engine is, in this exemplary embodiment, a diesel (compression ignition) engine of the two-stroke single-flow scavenge type, with a scavenge port 18 in the lower region of the cylinder 1 and a central exhaust valve 4 at the top of the cylinder. Or an Otto (spark ignition) engine. The scavenging air passes from the scavenging air receiver 2 to the scavenging port 18 of the individual cylinder 1. The piston 10 in the cylinder 1 compresses the scavenging air, fuel is injected from the fuel valves 50 and 51 in the cylinder cover 22, combustion occurs and exhaust gas is generated. When the exhaust valve (4) opens, the exhaust gas flows to the exhaust gas receiving portion (3) through the exhaust duct combined with the cylinder (1), and continues to the turbine (5) of the turbocharger (5) through the first exhaust conduit (19). After flowing to 6), this exhaust gas is discharged via the economizer 20 through the second exhaust conduit to the outlet 21 and into the atmosphere. The turbine 6 drives the compressor 7, from which fresh air is supplied via the shaft and via the air inlet 12. This compressor (7) delivers pressurized scavenging air to the scavenging air conduit (13) leading to the scavenging air receiver (2).

The scavenging air in this conduit (13) passes through the intercooler (14) for cooling of the scavenging air. In an exemplary embodiment, scavenging air leaves the compressor at about 200° C. and is cooled by an intercooler to a temperature between 36 and 80° C.

If the compressor 7 of the turbocharger 5 does not deliver sufficient pressure to the scavenge receiver 2, i.e. in low or partial load conditions of the engine, the cooled scavenge air is replaced by an electric motor 17 that pressurizes the scavenge flow. ) passes through the auxiliary blower 16 driven by . At higher engine loads, the turbocharger compressor (7) delivers sufficiently pressurized scavenging air, and then the auxiliary blower (16) is bypassed via the non-return valve (15).

The piston is connected to the crosshead (9) by a piston rod. The crosshead (9) is connected to the crankshaft (8) via a connecting rod. The rotational speed and position of the crankshaft 8 are measured by a sensor 40. The engine speed signal measured by the sensor 40 is transmitted to the controller 55, for example, via a signal line.

Each cylinder 1 is provided with an exhaust valve 4 together with two or more fuel valves 50 and a pressure sensor 42 . The pressure signal for each cylinder from the pressure sensor 42 is transmitted to the controller 55.

The engine is a dual fuel engine in one embodiment, in which two or more fuel valves 50 are dedicated to the first fuel and two or more fuel valves 50 are dedicated to the second fuel. Or two or more fuel valves are shared by two fuels.

The fuel valve 50 is controlled by a controller 55. For example, the controller 55 determines when the fuel valve opens, how long the fuel valve opens, and, in one embodiment, also determines the opening profile of the fuel valve 50. The fuel valve 50 is part of the fuel supply system 30. The signal for opening and closing the fuel valve 50 may be a fluid signal or a hydraulic signal. In embodiments where the signal for opening and closing the fuel valve is a fluid signal, such as a hydraulic signal, the controller 55 may send an electronic signal to an electronically controlled valve or pump, from which the hydraulic signal can be transmitted to the fuel valve 55. ) is transmitted.

In one embodiment, the fuel supply system 30 is configured to supply at least two different fuels. In one embodiment, one of the two fuels is fuel oil, such as fuel oil or heavy oil or methanol. In one embodiment, one of the two fuels is a gaseous fuel such as petroleum gas or natural gas. In one embodiment, the gaseous fuel is introduced or injected into the cylinder in a gaseous state. In other embodiments, the gaseous fuel is introduced or injected into the cylinder in a liquid state.

In one embodiment, the engine is a fuel driven engine. In a fuel-driven or gas-driven combustion process, the amount of fuel to be measured is determined as a function of the duty point of the internal combustion engine and specifiable target values for the power and/or speed of the internal combustion engine. The fuel-driven combustion process is particularly applicable during variable speed operation of internal combustion engines, in internal combustion engines in isolated operation, during engine start-up or when the internal combustion engine is idling. Applied engine controls include power controllers and/or speed controllers. Engines that operate exclusively on the diesel process are fuel-driven engines, regardless of whether the fuel is liquid or gaseous. Generally, fuel is injected immediately after TDC (Top Dead Center) and ignites immediately after injection. Therefore, the amount of fuel injected is the main control parameter of a fuel-driven engine.

In one embodiment, the engine is an air driven engine. In air-driven combustion processes, the amount of fuel to be measured is determined as a function of the duty point of the internal combustion engine and the target values specifiable for the fuel-air ratio in order to avoid knock problems (premature combustion) or a certain scavenging pressure and, in particular, a certain compression pressure. Therefore, applied engine controls typically include compression pressure controllers. Engines that operate exclusively according to the Otto process are air-driven engines, regardless of fuel type. Therefore, compressed air pressure is the main control parameter of air-driven engines.

In one embodiment, the engine is a combination of an air inlet and fuel driven engine. An example of such an engine is one in which a first amount of fuel is introduced into the combustion chamber before the compression stroke and an additional second amount of fuel is injected near the Top Dead Center (TDC). Injection of the second fuel quantity initiates ignition of both the second fuel quantity and the first fuel quantity in the combustion chamber. In large two-stroke engines, injection near TDC is usually immediately after TDC. In these engines, both the amount of fuel injected and the compression pressure are key control parameters, and the importance of both parameters can vary depending on engine load and speed.

In one embodiment, the internal combustion engine is a dual fuel engine and is fuel driven when running on a primary fuel and air driven when running on a secondary fuel.

Each exhaust valve 4 is provided with an exhaust valve actuator 46. In one embodiment, exhaust valve actuator 46 is a hydraulic actuator that receives commands by electronic signals from controller 55.

One or more combustion process parameters of the combustion process in cylinder 1 are controlled by controller 55 . The combustion process parameters are, for example, at least one of fuel amount, fuel inlet/injection start timing and exhaust valve closing timing. The combustion process parameter fuel quantity is correlated with the contribution of the relevant cylinder (1) to the torque delivered by the engine. The timing of the combustion process parameters of the start of fuel injection is correlated with the peak pressure of the relevant cylinder (this applies in particular to engines operating according to the diesel principle, as well as engines operating according to the Otto principle, in which fuel is introduced rather than injected). does not work). The combustion process parameter timing of exhaust valve closure is correlated with the combustion pressure in the relevant cylinder (1).

Figure 4 shows a first embodiment of the controller 55. In one embodiment, controller 55 includes an engine controller and multiple cylinder controllers.

The controller 55 receives the speed set, ie the desired engine speed, for example from the bridge of ship. The controller 55 receives the engine speed signal from the sensor 40, and the controller 55 compares the desired engine speed with the measured engine speed to obtain a speed deviation signal. The controller 55 includes a governor to which a speed deviation signal is supplied.

The governor is configured to determine the fuel index as a function of the deviation of the desired engine speed from the measured engine speed. That is, the governor is configured to determine the fuel index as a function of the speed deviation signal. The fuel index signal is a signal indicating the amount of fuel to be injected/injected to achieve the desired engine speed. The amount of fuel injected is directly correlated to the amount of torque delivered by the engine.

The controller 55 includes an exponent to common torque signal module configured to convert the fuel exponent to a common torque signal by applying the fuel exponent to a first predetermined map. The common indicated torque/exponent can also be considered to be proportional to the common average indicated pressure.

In this document, the expression "common" means applicable to all cylinders.

The predetermined first map is set from tests performed on a test bed at a factory where the engine is developed and/or manufactured, etc. The first predetermined map, in one embodiment, includes a table or algorithm that correlates fuel index to a common indicative torque.

A cylinder controller is connected to each cylinder (1). A common torque signal is sent to each cylinder controller.

Controller 55 includes a power calculation module (load calculation) configured to calculate an engine load signal representative of engine load. In one embodiment, the engine load signal represents actual engine load relative to a maximum engine load, such as maximum continuous rating. The power calculation module receives the exponential signal and the measured engine speed. In one embodiment, the load calculation module multiplies the engine speed by the fuel index and multiplies this result by a predetermined multiple set from test values or empirical values to reach the relative engine load, i.e., the maximum continuous rated percentage.

The controller 55 includes an engine operating mode module configured to determine a common peak pressure signal by applying the engine load signal to a second predetermined map and to determine a common compression pressure by applying the engine load signal to a third predetermined map. Includes.

The predetermined second map and third map are set in tests performed on a test bed at a factory where the engine is developed and/or manufactured, etc. The second predetermined map includes a table or algorithm that correlates peak pressure to engine load in one embodiment, and the third predetermined map includes a table or algorithm that correlates compression pressure to engine load in one embodiment. The second and third maps may take into account several other parameters such as ambient pressure, ambient temperature and engine speed, and may include offsets for friction losses, for example.

A common peak pressure signal and a common compression pressure signal are sent to all cylinder controllers.

Each cylinder controller receives a specific measured cylinder pressure from the pressure sensor 42 of the cylinder 1 to which the relevant cylinder controller is dedicated.

The cylinder controller is configured to calculate the actual cylinder-specific maximum pressure, the actual cylinder-specific compression pressure and the actual cylinder-specific average indicated pressure from the cylinder-specific pressure signal received from the pressure sensor 42 of the relevant cylinder 1. Afterwards, the average indicated pressure for each cylinder is displayed as the actual torque for each cylinder.

The actual pressure value per cylinder is preferably an arithmetic mean, particularly preferably the median of a plurality of consecutive pressure measurements, e.g. over a plurality of engine cycles, e.g. from 5 to 50 engine cycles, preferably from about 10 engine cycles. It is decided.

To obtain better signal quality and therefore higher control performance, the cylinder-specific pressure signal of the cylinder is measured by temporal filtering obtained over 5 to 50 engine cycles, preferably 7 to 15 combustion cycles. 1 This is a pressure signal.

Therefore, the actual pressure for each cylinder is the result of statistically evaluating the pressure measurement by the pressure sensor 42 of the relevant cylinder 1.

The cylinder controller is configured to adjust the common torque signal as a function of the deviation of the common torque signal from the actual cylinder-specific torque signal to obtain a cylinder-specific torque signal. Therefore, the cylinder controller continuously (or intermittently) calculates the error value as the difference between the cylinder-specific torque and the actual cylinder-specific torque and applies corrections based on the proportional and integral terms (PI regulator) to arrive at a cylinder-specific torque signal and related Forms closed-loop control for a specific cylinder (1).

In one embodiment, the controller 55 receives adjustment of common torque, adjustment of common peak pressure, and/or adjustment of common compression pressure. In this embodiment, the controller 55 determines the average for the adjustment of the common torque of all cylinders, the average or median of the adjustment for the common peak pressure of all cylinders, and/or the average or median of the adjustment for the compression pressure of the cylinders. It is configured to do so.

In this embodiment, the controller 55 allows the individual cylinder controllers to adjust maximum adjustments of per-cylinder torque, peak per-cylinder pressure, and/or per-cylinder compression pressure within a window defined by the respective averages plus or minus adjustments of predetermined magnitudes. It is configured to set limits for. For example, the adjustment window is plus or minus 5 bar from the calculated average. In this example, if the average per-cylinder peak pressure adjustment for all cylinders is plus 2 bar, then the individual cylinder controller can adjust the per-cylinder peak pressure adjustment between minus 3 bar and plus 7 bar.

The limiter limits the maximum correction to the common torque signal. If the correction of the common torque signal points in the same direction for all cylinders (1), the limiter allows a maximum correction up to the first threshold. If the correction of the common torque signal does not point in the same direction for all cylinders 1, the limiter allows a maximum correction up to a second threshold, which is lower than the first threshold. This prevents erroneous signals from destabilizing the system and allows for greater compensation if the deployment of all cylinders (1) is equal.

The controller 55 therefore calculates the average for all cylinders of the cylinder-specific adjustments of the torque signal and limits the cylinder-specific adjustments in a cycle of the torque signal to a predetermined maximum deviation of plus or minus from the calculated average of the adjustments of the torque signal. .

The controller 55 is configured to define a window as a predetermined maximum deviation, plus or minus, from the calculated average of the torque signal adjustments and to limit cylinder-specific adjustments in a cycle of the torque signal to adjustments within the window. The window is a range with a first range in the plus direction and a second range in the minus direction in the calculated average of the torque signal adjustment. The window depends on the torque signal and other combustion process parameters (pressure and combustion pressure). The positive range has a first predetermined size and the negative range has a second predetermined size. These sizes can be set at the factory, for example by running a test. The window should be large enough to accommodate the largest adjustments that typically occur, but small enough to exclude adjustments that may result from errors, such as erroneous sensor signals.

The controller 55 is configured to calculate an average of the cylinder-specific adjustments of the cylinder to the torque signal during one cycle or over multiple cycles of torque signal cycle adjustment. In one embodiment, the adjustment of combustion process parameter(s) is an adjustment over a single cycle.

The injection profile module converts cylinder-specific torque signals into cylinder-specific fuel valve profile signals. The injection profile module correlates the cylinder-specific torque signal with the injection profile by applying the specific torque signal to a predetermined fourth map. The fourth map may include an algorithm and/or a lookup table set in the test. The fuel valve profile signal for each cylinder is transmitted to the fuel valve 50 of the relevant cylinder and instructs the fuel valve 50 according to which profile the fuel valve 50 should be opened and closed, that is, the fuel valve opening duration and profile shape. . The fuel valve 50 delivers a cylinder-specific fuel quantity to the specific cylinder 1 associated with it in response to a fuel valve profile signal from the cylinder controller associated with the associated cylinder 1 .

The cylinder controller is configured to adjust the common peak pressure signal as a function of the deviation of the common peak pressure signal from the actual cylinder-specific peak pressure signal to obtain the cylinder-specific peak pressure signal. Therefore, the cylinder controller continuously (or intermittently) calculates the error value as the difference between the cylinder-specific torque and the actual cylinder-specific pressure and applies corrections based on the proportional and integral terms (PI regulator) to reach the cylinder-specific peak pressure signal. Forms closed-loop control for the specific cylinder (1) involved.

In the same way as described above for the torque signal, the limiter for the peak pressure signal limits the maximum correction for the common peak pressure signal. If the correction of the common peak pressure signal points in the same direction for all cylinders (1), the limiter allows a maximum correction up to the first threshold. If the correction of the common peak pressure signal does not point in the same direction for all cylinders 1, the limiter allows a maximum correction up to a second threshold, which is lower than the first threshold. This prevents erroneous signals from destabilizing the system and allows for greater compensation if the deployment of all cylinders (1) is equal.

The peak pressure module converts the peak pressure signal for each cylinder into a fuel injection timing signal for each cylinder. Here, the peak pressure module applies the peak pressure signal for each cylinder to a predetermined fifth map. The fifth predetermined map may include an algorithm and/or lookup table that correlates pressure to the start of fuel injection/injection. The algorithm and/or lookup table of the predetermined fifth map may be set by testing.

The fuel injection timing signal for each cylinder is transmitted to the fuel valve 50 of the relevant cylinder 1, and instructs the fuel valve 50 when the fuel valve begins to open, i.e., the time (angle) to start fuel inflow/injection. do. The fuel valve 50 of the relevant cylinder 1 starts the inflow/injection of a cylinder-specific amount of fuel into the specific cylinder 1 involved in response to an injection timing signal from the cylinder controller related to the relevant cylinder 1.

The cylinder controller is configured to adjust the common compression pressure signal as a function of the deviation of the common compression pressure signal from the actual cylinder-specific compression pressure signal to obtain the cylinder-specific compression pressure signal. Therefore, the cylinder controller continuously (or intermittently) calculates the error value as the difference between the cylinder-specific compression signal and the actual cylinder-specific compression pressure and applies corrections based on the proportional and integral terms (PI regulator) to the cylinder-specific compression pressure signal. reaches and forms closed-loop control for the specific cylinder (1) involved.

In the same way as described above for the torque signal and peak pressure signal, the limiter for the compression pressure signal limits the maximum correction for the common compression pressure signal. If the correction of the common compression pressure signal points in the same direction for all cylinders (1), the limiter allows a maximum correction up to the first threshold. If the correction of the common compression pressure signal does not point in the same direction for all cylinders 1, the limiter allows a maximum correction up to a second threshold, which is lower than the first threshold. This prevents erroneous signals from destabilizing the system and allows for greater compensation if the deployment of all cylinders (1) is equal.

The compression pressure module converts the cylinder-specific compression pressure signal into a cylinder-specific exhaust valve closing timing signal. Here, the compression pressure module applies the compression pressure signal for each cylinder to a predetermined fifth map. The sixth predetermined map may include an algorithm and/or a look-up table correlating the compression pressure to the closing timing of the exhaust valve 4. The algorithm and/or lookup table of the predetermined sixth map may be set by testing.

The cylinder-specific exhaust valve closing timing signal is transmitted to the fuel valve 50 of the relevant cylinder 1 and the exhaust valve actuator determines when the exhaust valve 4 should close, i.e. the time (angle) of closing the exhaust valve 4. Directed to (46). The exhaust valve actuator 46 of the associated cylinder 1 closes in response to an exhaust valve closing timing signal from the cylinder controller associated with the associated cylinder 1.

In one embodiment, the cylinder-specific torque signal (average indicated pressure) adjustment, cylinder-specific peak pressure adjustment, and cylinder-specific combustion pressure adjustment are transmitted back to the controller 55, and the average of the indicated pressure adjustments, the average of the peak pressure adjustments, and the combustion pressure adjustment are transmitted back to the controller 55. The average of pressure adjustments is calculated. Adjustments are performed periodically, for example every 1, 2, 5 or 10 engine revolutions. Averages for the combustion process parameters of all cylinders are also calculated periodically, preferably at the same cycle frequency as the regulation cycle. Controller 55 sets limits for cylinder-specific adjustments of each combustion process parameter relative to the calculated average of the relevant combustion process parameters. This limit may be in the form of a predetermined maximum deviation plus or minus from the calculated mean. The predetermined positive deviation may be different from the predetermined negative deviation.

A window is thus formed around the calculated average of the relevant process parameters. The predetermined plus and minus deviations depend on the process parameters. Integrator windup is variable, allowing larger adjustments for larger average adjustments in torque, peak pressure, and combustion pressure.

The cylinder controller is configured to individually control the cylinders 1 of the engine without consideration of maintaining cylinder balance, that is, without cylinder balance. Accordingly, each cylinder (1) provides a cylinder-specific feedback loop control over the cylinder-specific average indicated pressure (torque) and/or by providing a cylinder-specific feedback loop control over the cylinder-specific peak pressure and/or by providing a cylinder-specific feedback loop control over the cylinder-specific compression pressure. It operates according to design specifications by providing cylinder-specific feedback loop control for each cylinder. No cylinder balancing is required as all cylinders (1) operate according to design specifications. This is especially useful after changing fuel from one fuel to another in a dual fuel engine. In existing engines, this fuel change requires manual recalibration to ensure the engine operates optimally after the fuel change. Using a controller according to the present disclosure, manual recalibration is not required after changing fuel. In particular, peak pressure and torque are very important during the transition from fuel oil to S secondary fuel (e.g. gas), and are automatically guaranteed/adjusted through the controller of the present disclosure.

However, depending on the situation, it may be necessary to operate one or more cylinders that differ from design specifications. For example, sometimes the cylinder 1 is in a condition where it is judged that there is a significant risk of cylinder liner scuffing (seizing), which occurs due to lack of cylinder lubrication. If the load is not reduced it may be necessary to reduce the load on the cylinder which gives an indication that scuffing is occurring or is about to occur.

Therefore, in the embodiment of the controller shown in Figure 5, each cylinder controller has a cylinder-specific cylinder offset module for each cylinder (1). Includes. In this embodiment, structures and features that are the same or similar to corresponding structures and features previously described or shown herein are denoted by the same reference numerals as previously used for simplicity. This embodiment of controller 55 is essentially the same as the embodiment of Figure 4 except for the addition of a per-cylinder offset module.

The per-cylinder offset module includes a per-cylinder cylinder offset module for each cylinder, wherein the per-cylinder offset module is configured to offset a common torque signal, a common peak pressure signal, and/or a common compression pressure signal for the specific cylinder involved. The offset can be operator guided or automatically guided by a signal from the cylinder controller or a sensor which causes the controller to introduce an offset setting for a particular cylinder (1). For example, knocking of a specific cylinder can be detected by a sensor. In response to these knock sensors, the compression pressure of a particular cylinder is reduced by the controller 55 to drop the temperature of the combustion chamber and reduce the risk of knocking. Therefore, a cylinder-specific offset is introduced for that cylinder. Additionally, in one embodiment, the controller 55 is configured to increase the air-to-fuel ratio by reducing the fuel quantity via an offset of the per-cylinder offset relative to the fuel quantity to be injected.

Therefore, the cylinder offset module outputs the torque set value for each cylinder, the peak pressure set value for each cylinder, and the compression pressure set value for each cylinder. The cylinder-specific set value is a function of the difference between the actual cylinder-specific torque, cylinder-specific peak pressure, and cylinder-specific compression pressure, and is adjusted in the same way as shown in the embodiment of FIG. 4 above to obtain the cylinder-specific torque, cylinder-specific peak pressure, and cylinder-specific compression pressure. Compression pressure is reached respectively.

Figure 6 shows another embodiment of the controller 55. In this embodiment, structures and features that are the same or similar to corresponding structures and features previously described or shown herein are denoted by the same reference numerals as previously used for simplicity. This embodiment of controller 55 is essentially the same as that of Figure 5 except for the addition of a fuel index to the profile period module. The fuel index signal to profile duration module is configured to convert the fuel index signal to a common profile duration signal.

Each cylinder controller receives a common profile duration signal. The cylinder controller is configured to adjust the common fuel delivery duration signal as a function of the deviation of the common fuel delivery duration signal from the cylinder-specific torque signal to obtain a cylinder-specific fuel profile duration signal.

Adding a common profile duration signal makes the engine more robust to fluctuations in fuel quality. In particular, gaseous fuels tend to have different characteristics. For example, the gas LCV (lower heating value) can vary by up to 30-50%.

In one embodiment, the common torque signal corresponds to the average indicated cylinder pressure for all cylinders, and the cylinder-specific torque signal corresponds to the average indicated cylinder pressure for the specific cylinder involved.

Various aspects and embodiments have been described in connection with various embodiments herein. However, other modifications to the disclosed embodiments may be understood and made by those skilled in the art when practicing the claimed subject matter upon study of the drawings, disclosure, and appended claims. In the claims, the word "comprising" does not exclude another element or step, and the indefinite article "an" or "an" does not exclude a plurality. A single processor, controller or other unit may not exclude multiple elements or steps recited in the claims. The mere fact that certain measures are recited in different dependent claims does not indicate that their combination cannot be used to advantage.

Reference signs used in the claims should not be construed as limiting the scope. Unless otherwise indicated, the drawings are intended to be read in conjunction with the specification (e.g., cross-hatching, arrangement of parts, scale, scale, etc.) and are to be considered a part of the entire written description of the present disclosure.

1: cylinder
4: Exhaust valve
9: Crosshead
30: Fuel delivery system
42: Pressure sensor
46: Exhaust valve operating system
55: controller

Claims (40)

In a large low-speed two-stroke single-flow scavenging turbocharged internal combustion engine with a crosshead (9),
A plurality of cylinders (1) having:
- exhaust valve (4),
- an exhaust valve actuating system (46) for operating said exhaust valve (4),
- a fuel delivery system (30) for delivering a first amount of fuel to the specific cylinder (1)
- a pressure sensor 42 for generating a pressure signal for each cylinder indicating the pressure of the specific cylinder 1,
an exhaust gas driven turbocharger (5) for pressurizing the scavenging air of the cylinder (1); and
a controller (55) configured to receive or determine:
A common torque signal representing the torque transmitted by the internal combustion engine,
a common peak pressure signal representing the peak cylinder pressure to be realized in said cylinder (1), and
A common compression pressure signal representing the compression pressure to be realized in the cylinder (1),
The controller 55 receives the pressure signal for each cylinder,
a) The controller 55 derives an actual cylinder-specific torque signal representing the torque delivered by the specific cylinder 1 from the cylinder-specific pressure signal, and uses the actual cylinder-specific torque signal to obtain the cylinder-specific torque signal. configured to adjust the common torque signal as a function of the deviation of the common torque signal from and deliver a certain amount of fuel to the specific cylinder (1) as a function of the cylinder-specific torque signal,
b) The controller 55 derives an actual peak pressure signal for each cylinder indicating the peak pressure of the specific cylinder 1 from the pressure signal for each cylinder, and calculates the peak pressure for each cylinder to obtain the peak pressure signal for each cylinder. configured to adjust the common peak pressure signal as a function of the deviation of the common peak pressure signal from the signal and to determine the start time of delivery of the fuel quantity to the specific cylinder (1) as a function of the cylinder-specific peak pressure signal,
c) The controller 55 derives an actual cylinder-specific compression pressure signal representing the compression pressure of the specific cylinder 1 from the cylinder-specific pressure signal, and calculates the actual cylinder-specific compression pressure to obtain the cylinder-specific compression pressure signal. a crosshead configured to adjust the common compression pressure signal as a function of the deviation of the common compression pressure signal from the signal and determine a closing time of the exhaust valve of the specific cylinder as a function of the cylinder-specific compression pressure signal. (9) A large, low-speed, two-stroke, single-flow, scavenging, turbocharged internal combustion engine. According to paragraph 1,
A large, low-speed, two-stroke, single-flow, scavenging, turbocharged internal combustion engine with a crosshead (9), wherein the internal combustion engine is fuel-driven or air-driven. According to paragraph 1,
A large, low-speed, two-stroke, single-flow, scavenging, turbocharged internal combustion engine with a crosshead (9), wherein the internal combustion engine is partly fuel driven and partly air driven. According to any one of claims 1 to 3,
The internal combustion engine is a dual fuel engine, the fuel delivery system (30) is configured to process at least two different fuels, the cylinder (1) each having at least one fuel valve (50) for delivering a first fuel. and a crosshead (9) provided with at least one fuel valve (50) for delivering secondary fuel. According to clause 4,
The internal combustion engine is fuel-driven when operating on the first fuel and air-driven when operating on the second fuel. According to paragraph 1,
The controller 55 receives a desired engine speed and receives a measured engine speed, and the controller 55 includes a governor configured to determine a fuel index signal as a function of the deviation of the desired engine speed from the measured engine speed. A large, low-speed, two-stroke, single-flow, scavenging, turbocharged internal combustion engine with a crosshead (9), comprising: According to clause 6,
The controller (55) is configured to convert the fuel index signal to the common torque signal by applying the fuel index signal to a first predetermined map. Charging internal combustion engine. In clause 7,
The controller 55 comprises a power calculation module configured to calculate an engine load signal indicative of engine load, the power calculation module comprising a crosshead 9, which receives the fuel index signal and the measured engine speed. A large, low-speed, two-stroke, single-flow scavenging turbocharged internal combustion engine. According to clause 8,
The controller 55 determines the common peak pressure signal by applying the engine load signal to a second predetermined map, and/or determines the common compression pressure by applying the engine load signal to a third predetermined map. A large, low-speed, two-stroke, single-flow, scavenging, turbocharged internal combustion engine with a crosshead (9). According to paragraph 1,
The controller (55) comprises a profile duration module that receives a fuel index signal, the profile duration module configured to convert the fuel index signal into a common fuel delivery duration signal. A large, low-speed, two-stroke, single-flow scavenging turbocharged internal combustion engine. According to clause 10,
wherein the controller (55) is configured to adjust the common fuel delivery duration signal as a function of the deviation of the common fuel delivery duration signal from the cylinder-specific torque signal to obtain a cylinder-specific fuel delivery duration signal. (9) A large, low-speed, two-stroke, single-flow, scavenging, turbocharged internal combustion engine. According to clause 11,
The controller 55 is configured to determine a cylinder-specific injection profile as a function of the cylinder-specific torque signal or as a function of the cylinder-specific fuel delivery duration signal, and the fuel delivery system 30 is configured to determine the cylinder-specific injection profile. A large, low-speed, two-stroke, single-flow, scavenging, turbocharged internal combustion engine with a crosshead (9), which transfers the fuel quantity to the specific cylinder (1) by opening one or more fuel valves (50) according to the present invention. According to paragraph 1,
The fuel delivery system (30) begins delivery of the fuel quantity to the specific cylinder (1) by opening one or more fuel valves (50) in accordance with the start of the delivery timing of the fuel quantity determined by the controller (55). Large low-speed two-stroke single-flow scavenging turbocharged internal combustion engine with crosshead (9). According to paragraph 1,
If the internal combustion engine has element a),
the controller (55) is configured to limit the magnitude of the adjustment of the common torque signal to a first threshold when the adjustment for the other cylinder (1) is in the same direction,
The controller (55) is configured to limit the magnitude of the adjustment of the common torque signal to a second threshold when the adjustment for the other cylinder (1) is in the opposite direction, and/or
If the internal combustion engine has element b),
the controller (55) is configured to limit the magnitude of the adjustment of the common peak pressure signal to a first threshold when the adjustment for the other cylinder (1) is in the same direction,
The controller (55) is configured to limit the magnitude of the adjustment of the common peak pressure signal to a second threshold when the adjustment for the other cylinder (1) is in the opposite direction, and/or
If the internal combustion engine has element c),
the controller (55) is configured to limit the magnitude of the adjustment of the common compression pressure signal to a first threshold when the adjustment for the other cylinder (1) is in the same direction,
Characterized in that the controller (55) is configured to limit the magnitude of the adjustment of the common compression pressure signal to a second threshold when the adjustment for the other cylinder (1) is in the opposite direction. Large low-speed two-stroke single-flow scavenging turbocharged internal combustion engine with crosshead (9). According to clause 14,
A large, low-speed, two-stroke, single-flow, scavenging, turbocharged internal combustion engine with a crosshead (9), wherein the second threshold is lower than the first threshold. According to paragraph 7 or 9,
Characterized in that the first, second and/or third predetermined maps are predetermined at the engine factory from tests of the internal combustion engine or an identical or similar internal combustion engine. Single-stroke scavenging turbocharged internal combustion engine. According to paragraph 1,
The common torque signal corresponds to the average indicated cylinder pressure for all cylinders, and the cylinder-specific torque signal corresponds to the average indicated cylinder pressure for the specific cylinder. Scavenging turbocharged internal combustion engine. According to paragraph 1,
The controller 55 includes a per-cylinder offset module for each cylinder, the per-cylinder offset module configured to offset the common torque signal, the common peak pressure signal and/or the common compression pressure signal for the specific cylinder concerned. A large, low-speed, two-stroke, single-flow, scavenging, turbocharged internal combustion engine with a crosshead (9), comprising: According to clause 18,
A large low-speed two-stroke single-flow scavenging turbocharged internal combustion engine with a crosshead (9), wherein the cylinder-specific offset module is controlled manually or automatically. According to paragraph 1,
The controller (55) is configured to individually control the cylinders (1) of the internal combustion engine without considering cylinder balance. According to paragraph 1,
The controller 55 is configured to continuously calculate an error value as the difference between the torque for each cylinder and the actual torque for each cylinder when the internal combustion engine has element a) and apply correction based on the proportional term and the integral term,
The controller 55 is configured to continuously calculate an error value as the difference between the peak pressure for each cylinder and the actual peak pressure for each cylinder when the internal combustion engine has element b) and apply correction based on the proportional term and the integral term. become,
The controller 55 is configured to continuously calculate an error value as the difference between the compression pressure for each cylinder and the actual compression pressure for each cylinder when the internal combustion engine has element c) and apply correction based on the proportional term and the integral term. A large, low-speed, two-stroke, single-flow, scavenging, turbocharged internal combustion engine with a crosshead (9). According to paragraph 1,
The fuel delivery system (30) is configured to deliver a first fuel quantity and/or a second fuel quantity to the specific cylinder (1). A method of operating a large, low-speed, two-stroke, single-flow, scavenging, turbocharged internal combustion engine with a crosshead (9), comprising:
The internal combustion engine is,
A plurality of cylinders (1) having: and
- exhaust valve (4),
- an exhaust valve actuating system (46) for operating said exhaust valve (4),
- a fuel delivery system (30) for delivering a first amount of fuel to the specific cylinder (1)
- a pressure sensor 42 for generating a pressure signal for each cylinder indicating the pressure of the specific cylinder 1,
It includes an exhaust gas driven turbocharger (5) for pressurizing the scavenging air of the cylinder (1),
The method is:
At least one combustion process among the fuel amount of the cylinder (1), fuel injection start timing, and exhaust valve closing timing as a function of the pressure signal for each cylinder and a cylinder-specific set value that is a cylinder-specific offset of the common set value for all cylinders (1) Method of operating a large, low-speed, two-stroke, single-flow, scavenging, turbocharged internal combustion engine with a crosshead (9), including a closed-loop control of parameters on a cylinder-by-cylinder basis. delete According to clause 23,
A method of operating a large, low-speed, two-stroke, single-flow, scavenging, turbocharged internal combustion engine with a crosshead (9), wherein the closed loop control is performed without any consideration for maintaining cylinder balance. According to clause 23,
A method of operating a large, low-speed, two-stroke, single-flow, scavenging, turbocharged internal combustion engine with a crosshead (9), wherein the closed loop control applies corrections based on proportional and integral terms. According to clause 23,
The common settings are:
a common torque signal representing the torque transmitted by the internal combustion engine, and/or a common peak pressure signal representing a peak cylinder pressure to be realized in the cylinder, and/or a common compression pressure signal representing a compression pressure to be realized in the cylinder, Method of operating a large, low-speed, two-stroke, single-flow, scavenging, turbocharged internal combustion engine with crosshead (9). According to clause 23,
A method of operating a large, low-speed, two-stroke, single-flow, scavenging, turbocharged internal combustion engine with a crosshead (9), wherein the closed loop control uses cylinder pressure measured for each cylinder as a reference value. According to clause 28,
The average indicated cylinder pressure for each cylinder is derived from the cylinder pressure measured for each cylinder, and/or the peak pressure for each cylinder is derived from the cylinder pressure measured for each cylinder, and/or the compression pressure for each cylinder is derived from the cylinder pressure measured for each cylinder. Method of operating a pressure-derived, large, low-speed, two-stroke, single-flow, scavenging, turbocharged internal combustion engine with crosshead (9). In a large low-speed two-stroke single-flow scavenging turbocharged internal combustion engine with a crosshead (9),
A plurality of cylinders (1) having:
exhaust valve (4);
an exhaust valve operating system (46) for operating the exhaust valve (4) and
A fuel delivery system (30) for delivering a first amount of fuel to the specific cylinder (1)
an exhaust gas driven turbocharger (5) for pressurizing the scavenging air of the cylinder (1); and
A controller 55 configured to control one of the combustion process parameters of fuel amount, fuel injection start timing, and exhaust valve closing timing for each cylinder,
The controller 55 adjusts the combustion process parameters ( are configured to individually control the
The controller is,
Calculate an average for the cylinders of the cylinder-specific adjustments of the combustion process parameter(s), and
A large crosshead (9), characterized in that it is configured to limit the cylinder-specific adjustment in a cycle of the combustion process parameter(s) to a predetermined maximum deviation range from the calculated mean of the combustion process parameter adjustment. Low-speed two-stroke single-flow scavenging turbocharged internal combustion engine. According to clause 30,
The controller 55 defines a window as a predetermined maximum deviation range from the calculated mean of the combustion process parameter adjustment,
A large, low-speed, two-stroke, single-flow, scavenging, turbocharged internal combustion engine with a crosshead (9), configured to limit the cylinder-specific adjustments in a cycle of the combustion process parameter(s) to adjustments within the window. According to clause 31,
The range of the window has a first range in the plus direction and a second range in the minus direction from the calculated average of the combustion process parameter adjustments. Turbocharged internal combustion engine. According to clause 32,
A large, low-speed, two-stroke, single-flow, scavenging, turbocharged internal combustion engine with a crosshead (9), wherein the window varies depending on the combustion process parameters. According to claim 32 or 33,
The large low-speed two-stroke single-flow scavenging turbocharged internal combustion engine with a crosshead (9), wherein the degree of plus has a first predetermined magnitude, and the degree of minus has a second predetermined magnitude. According to clause 30,
The controller 55 is configured to calculate an average of the cylinder-by-cylinder adjustments to the combustion process parameter(s) during one or multiple cycles of the periodic adjustment of the combustion process parameters. ) A large, low-speed, two-stroke, single-flow, scavenging, turbocharged internal combustion engine. According to clause 29,
A method of operating a large, low-speed, two-stroke, single-flow, scavenging, turbocharged internal combustion engine with a crosshead (9), wherein the adjustment of the combustion process parameter(s) is for a single cycle. According to clause 29,
A method of operating a large, low-speed, two-stroke, single-flow, scavenging, turbocharged internal combustion engine with a crosshead (9), wherein the at least one combustion process parameter includes fuel quantity, fuel injection start timing and/or exhaust valve closing timing. According to clause 29,
Large, low-speed, two-stroke, single-flow scavenging turbocharging with crosshead (9), wherein the cylinder-specific setpoint for the combustion process parameter(s) is an offset of the common setpoint for the combustion process parameter(s). How to operate an internal combustion engine. According to clause 29,
The operating conditions of the internal combustion engine are one or more of engine speed, engine load, cylinder peak pressure, cylinder combustion pressure, cylinder average indicated pressure, scavenging pressure fuel type, ambient humidity and ambient temperature. How to operate a two-stroke, single-flow, turbocharged internal combustion engine. A method of operating a large, low-speed, two-stroke, single-flow, scavenging, turbocharged internal combustion engine with a crosshead (9), comprising:
The internal combustion engine is,
A plurality of cylinders (1) having: and
exhaust valve (4);
an exhaust valve operating system (46) for operating the exhaust valve (4),
A fuel delivery system (30) for delivering a first amount of fuel to the specific cylinder (1),
It includes an exhaust gas driven turbocharger (5) for pressurizing the scavenging air of the cylinder (1),
The method is:
Controlling at least one combustion process parameter of fuel amount, fuel injection start timing, and exhaust valve closing timing for each cylinder; and
Individually controlling the combustion process parameter(s) of the cylinder 1 as a function of the operating conditions of the internal combustion engine by periodically adjusting common or cylinder-specific setpoints for the combustion process parameter(s) on a cylinder-by-cylinder basis. It includes;
calculating an average of the cylinder-specific adjustments to said combustion process parameter(s);
determining a window around the calculated mean of adjustment of the combustion process parameter(s); and
limiting the cylinder-specific adjustments in a cycle of the combustion process parameter(s) to a predetermined maximum deviation range from the calculated average of the combustion process parameter adjustments. How to operate a large, low-speed, two-stroke, single-flow, scavenging, turbocharged internal combustion engine included.

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