JPWO2019175951A1 - Ship power system - Google Patents

Abstract

In a dual fuel engine (3) that can use a gas engine and a diesel engine as main fuels, a first propulsion device (3A) is driven by being connected to one engine (3A) via a first clutch (9A). 5A) and a propulsion device side output sensor (14A) provided between the engine (3A) and the first clutch (9A). A firefighting apparatus (6) equipped with a fire extinguishing pump (11) connected to the engine (3A) via a second clutch (18) and driven, and the engine (3A) and the second clutch (18). It was provided with a work device side output sensor (19) provided between them. A second propulsion device (5B) connected to the other engine (3B) via a first clutch (9B) and driven, and provided between the engine (3B) and the first clutch (9A). It was equipped with a propulsion device side output sensor (14B).

Description

The present invention relates to a ship power system in which an engine that uses both gas fuel and liquid fuel as a main fuel is mounted as an engine of a propulsion device, and the output of the engine can be used for a work device other than propulsion. ..

As an example of the above-mentioned power system of a ship, a power device of a work ship equipped with a fire fighting apparatus described in Patent Document 1 has been proposed. The power unit described in Patent Document 1 uses a diesel engine as the main engine. In the power unit of this work ship, power is taken out via a wheel to a propulsion shaft system connected to a propeller of a work ship having a main engine such as a diesel engine, and a fire pump provided as an auxiliary machine is driven to discharge seawater. Firefighting equipment is provided.
This power system detects the overload of the main engine by the load detection device during firefighting work, and reduces the wing angle of the propulsion unit to suppress the overload of the main engine. In addition, when the fire pump is stopped, the clutch provided in the pump drive shaft system is disengaged from the power of the main engine to prevent the transmission of power.

On the other hand, from the viewpoint of reducing exhaust gas and protecting the environment, attempts have been made to mainly use a gas engine that can use gaseous fuel as the main fuel instead of the diesel engine that uses liquid fuel as the main fuel. Gas engines are mainly used as the main engine of large ships such as LNG and tankers, and can only be operated within a narrow range of the air-fuel ratio that can be burned, so it was difficult to respond quickly to sudden load fluctuations. .. Therefore, it is not suitable for a work ship equipped with a work device such as a fire fighting apparatus, and the power device of the work ship described in Patent Document 1 also takes out power from a diesel engine and uses it as a power source.

Jikken Sho 62-23359

By the way, in recent years, regulations on the emission of air pollutants emitted from ships have become more stringent, centered on international treaties. For example, in some sea areas called ECA, stricter regulations are imposed on the emission of sulfur oxides and nitrogen oxides.

However, the power unit of the work ship described in Patent Document 1 uses a diesel engine as the main engine, and does not sufficiently meet the above-mentioned requirements for air pollutant emission regulation.

The present invention has been made in view of the above-mentioned problems, and it is possible to use gaseous fuel as a main fuel and perform strict combustion control in response to load fluctuations not only as a propulsion device but also as a drive source for a work device. The purpose is to provide a ship power system that enables it.
Another object of the present invention is to provide a power system for a ship that uses gaseous fuel as a main fuel and can quickly respond to sudden load fluctuations or large load fluctuations to drive a work device. It is to be.

The ship power system according to the present invention is between an engine that can use gaseous fuel as a main fuel, a propulsion device that is connected to the engine via a first clutch and is driven, and between the engine and the first clutch. The propulsion device side output sensor provided in the engine, the work device connected to the engine via the second clutch and driven, and the work device side output sensor provided between the engine and the second clutch. It is characterized by having.
According to the present invention, the output of the engine that drives the propulsion device is measured by the propulsion device side output sensor while closing the first clutch and opening the second clutch to drive the propulsion device. The first clutch is opened and the second clutch is closed to drive the working device, and the output of the engine driving the working device is measured by the output sensor on the working device side. In an engine that uses gaseous fuel, it is relatively difficult to obtain an accurate fuel supply amount compared to liquid fuel because the gas used as fuel is an elastic body, so the output of the actual engine is measured by an output sensor. , The engine is controlled based on the measured value. With the propulsion device side output sensor and the work device side output sensor, the actual output of the engine is accurate, including the loss due to the resistance of the transmission system and clutch, regardless of whether the propulsion device is driven or the work device is driven. It can be measured and the engine that uses gaseous fuel as the main fuel can be strictly controlled.

Further, the working apparatus is a fire-fighting apparatus for discharging water.
The output sensor on the work device side can accurately measure the actual output of the engine when driving the fire fighting apparatus, and can strictly control the drive of the engine.

Further, it is characterized by being provided with a control device that closes the first clutch and opens the second clutch to drive the propulsion device, and opens the first clutch and closes the second clutch to drive the working device. And.
By switching the opening and closing of the first clutch and the second clutch by the control device, the drive of the propulsion device and the drive of the work device can be switched.

Further, it is preferable to control the engine by the total of the output measurement value by the propulsion device side output sensor and the output measurement value by the work device side output sensor.
A more accurate engine output value can be obtained by taking the sum of the output measurement value by the propulsion device side output sensor and the output measurement value by the work device side output sensor. For example, when the propulsion device is being driven, most of the engine output is measured by the propulsion device side output sensor, but the work device side output sensor also has a certain amount of output due to the drag resistance of the clutch in the open state and mechanical loss. Indicates a value. Therefore, by taking the sum of the output values of both output sensors, it is possible to measure the output value of the engine more accurately.

Further, it is preferable to control the engine rotation speed when the output measurement value by the propulsion device side output sensor and / or the output measurement value by the work device side output sensor exceeds the upper limit value.
In operation in an operation mode using gaseous fuel as the main fuel (also referred to as "gas mode"), when the output value by the propulsion device side output sensor or the output value by the work device side output sensor exceeds the upper limit value for a predetermined time, Auto slowdown control is performed to forcibly reduce the engine speed. If the engine output becomes excessive when operating in gas mode, knocking and misfire are likely to occur. Therefore, when the output value of the output sensor exceeds the upper limit, the engine is forcibly reduced in rotation speed. Reduce the output to prevent knocking and misfire.
As the upper limit value, either or both of the upper limit value of the power output by the engine and the upper limit value of the torque can be adopted. Further, not only a single upper limit value can be set, but also an upper limit value of torque that changes according to the engine speed can be set.

Further, the propulsion device side output sensor and the work device side output sensor are preferably torque sensors that measure the torque actually applied to the propulsion shaft of the engine.
A torque sensor is used as the propulsion device side output sensor and the work device side output sensor to measure the torque actually applied to the propulsion shaft of the engine. The output (power) of the engine can be obtained from the product of the torque value obtained by the torque sensor and the rotation speed of the engine obtained by the rotation speed sensor.

Further, the ship power system according to the present invention uses gas fuel as the main fuel when shifting from the state of driving the propulsion device to the state of driving the work device during operation in the operation mode in which the gas fuel is the main fuel. Temporarily switch from the operation mode to the operation mode using liquid fuel as the main fuel (also referred to as "diesel mode") to operate at least one of the first clutch and the second clutch, and then operate the liquid fuel. It is characterized in that it returns from the operation mode using the main fuel to the operation mode using the gaseous fuel as the main fuel.
According to the present invention, when shifting from the state of driving the propulsion device to the state of driving the working device during operation in the mode using gas fuel as the main fuel, the operation mode of gas fuel is changed to the operation mode of liquid fuel. It is temporarily switched to open and close the first clutch and the second clutch. The engine operation mode using gaseous fuel is easily affected by load fluctuations, and the disturbance caused by opening and closing each clutch may hinder the smooth operation of the engine. However, the clutch is temporarily switched to the diesel mode, which is resistant to load fluctuations. By opening and closing, stable switching operation can be performed without being affected by load fluctuations.

Further, the ship power system according to the present invention uses gas fuel as the main fuel when shifting from the state of driving the work device to the state of driving the propulsion device during operation in the operation mode in which the gas fuel is the main fuel. Temporarily switch from the operation mode using liquid fuel to the operation mode using liquid fuel as the main fuel, operating at least one of the second clutch or the first clutch, and then from the operation mode using liquid fuel as the main fuel. It is characterized by returning to the operation mode using gaseous fuel as the main fuel.
In the present invention, when returning from the state of driving the working device to the state of driving the propulsion device during operation in the mode using gas fuel as the main fuel, the mode is temporarily switched to the diesel mode using liquid fuel as the main fuel. , The first and second clutches are opened and closed in the diesel mode. Since the engagement of the first clutch to the propulsion device side involves a relatively large disturbance, by switching to the diesel mode and closing the first clutch, a stable switching operation is performed without being affected by load fluctuations. Can be done.

Further, the control device shifts from the gas mode using gas fuel as the main fuel to the diesel mode using liquid fuel as the main fuel in order to open one of the first clutch and the second clutch and close the other. It is preferable to include a diesel mode transition means and a gas mode transition means for shifting from the diesel mode to the gas mode after the operation of opening one of the first clutch and the second clutch and closing the other is completed.
Diesel mode that is resistant to load fluctuations because the engine operation mode using gaseous fuel is easily affected by load fluctuations and the disturbance caused by the opening and closing of the first and second clutches may hinder the smooth operation of the engine. By temporarily shifting to the above and opening and closing the first clutch and the second clutch, stable switching operation can be performed without being affected by load fluctuations. After that, by shifting to the gas mode, the operation with less adverse effect on the environment can be performed.

Further, the ship power system according to the present invention is a ship power system provided with a plurality of engines that can use both gaseous fuel and liquid fuel as main fuels, and one engine side has a first engine. A propulsion device connected and driven via a clutch of 1, a propulsion device side output sensor provided between the engine and the first clutch, and a propulsion device connected to the engine via a second clutch and driven. The work device, the output sensor on the work device side provided between the engine and the second clutch, and the first clutch are closed and the second clutch is opened to drive the propulsion device, and the first clutch is released. A control device that opens and closes the second clutch to drive the work device, and another propulsion device that is connected to another engine via a third clutch and is driven on the other engine side. , Another propulsion device side output sensor provided between the other engine and the third clutch is provided, and the third clutch is closed by the control device to drive the other propulsion device.
According to the present invention, when the work device is driven by one engine side, the propulsion of the ship can be continued by propelling the other propulsion device by the other engine based on the output sensor on the other propulsion device side. it can. In particular, when a fire-fighting apparatus for discharging water is provided as a work device, a reaction force is generated due to the water discharge, but the reaction force can be offset by continuing the propulsion of the ship, and the water discharge work can be performed in a stable state.

According to the ship power system according to the present invention, in the propulsion shaft of an engine that can be operated using gaseous fuel as a main fuel, a propulsion device side output sensor is provided between the engine and the first clutch, and the engine and the second clutch are provided. Since the work device side output sensor is provided between the clutch and the clutch, the output value of the engine can be detected and controlled by each sensor, and not only the propulsion device but also the work device can be driven.
Moreover, the output actually output by the engine can be measured more accurately, including the loss due to the resistance of the transmission system and clutch, and even when each clutch is open, the output including the resistance is included. Can be measured.

It is explanatory drawing which shows the whole structure of the ship provided with the firefighting apparatus by embodiment of this invention. It is explanatory drawing which shows the structure of the engine, the propulsion apparatus, and the firefighting apparatus in the ship by embodiment. It is explanatory drawing which shows the whole structure of the engine shown in FIG. It is explanatory drawing of the engine which shows the diesel mode. It is explanatory drawing of the engine which shows the gas mode. In the first embodiment, it is a flowchart which shows the process of switching from the drive of a propulsion apparatus to the drive of a firefighting apparatus. It is a flowchart which shows the process of switching from the drive of a firefighting apparatus to the drive of a propulsion apparatus. In the second embodiment, it is a flowchart which shows the process of switching from the drive of a firefighting apparatus to the drive of a propulsion apparatus. It is a flowchart which shows the control of auto slowdown.

Hereinafter, the power system of the ship 1 according to the embodiment of the present invention will be described with reference to FIGS. 1 to 8.
The ship 1 shown in FIG. 1 shows a basic configuration of a marine propulsion device for a work ship such as a tugboat. This ship 1 is equipped with a dual fuel engine 3 as the engine of the main engine, and operates by switching between two modes, a gas mode in which gaseous fuel is used as the main fuel and a diesel mode in which liquid fuel is used as the main fuel. Is possible.

This ship 1 can switch the transmission direction of the driving force of the dual fuel engine 3 as the engine of the main engine, and can discharge the seawater pumped from the sea by the propulsion device 5 equipped with the propeller 5a and the water discharge nozzle 6a. The device 6 and the device 6 can be selectively driven.
The ship 1 shown in FIG. 1 has, for example, an azimuth thruster (clutch separate type azimuth thruster) 8 as a marine propulsion device. The azimuth thruster 8 does not have to be installed on the ship 1 according to the present embodiment.

In the ship 1 shown in FIG. 1, a first clutch 9 serving as a main clutch is provided between the rear end side of driving the dual fuel engine 3 as the main engine and the azimuth thruster 8. A propulsion device 5 provided with a propeller 5a is connected to the rear end side of the azimuth thruster 8. The first clutch 9 is a slip clutch, which drives the propeller 5a of the propulsion device 5 by slip-controlling the maximum rotation speed of the dual fuel engine 3 to reduce it to the required rotation speed.
A speed-increasing gear 10 may be connected to the fire-fighting apparatus 6 installed on the front end side of the dual fuel engine 3. Seawater is discharged from the water discharge nozzle 6a by the fire pump 11 provided in the fire fighting apparatus 6.

Next, with reference to FIG. 2, the configuration of the marine propulsion device of the ship 1 shown in FIG. 1 will be described more specifically. The same configuration as the basic configuration of the marine propulsion device of the ship 1 shown in FIG. 1 will be described based on the specific arrangement configuration shown in FIG. In FIG. 2, a specific configuration will be described by adding A and B to the same reference numerals for a configuration in which a pair of each member of the ship 1 shown in FIG. 1 is provided.
In the ship 1 shown in FIG. 2, for example, two dual fuel engines (hereinafter, may be simply referred to as engines) 3 are installed in parallel, one of which is a dual fuel engine 3A and the other of which is a dual fuel engine 3B. .. The dual fuel engines 3A and 3B are each equipped with an ECU. The propulsion mechanism including the dual fuel engine 3A on the port side is the first marine propulsion device 20A, and the propulsion mechanism including the dual fuel engine 3B on the starboard side is the second marine propulsion device 20B.

In ship 1, many tugboats and workboats having a fire-fighting function are provided with a total of two engines 3A and 3B on both sides in parallel. As a result, when one dual fuel engine 3A drives the fire pump 11 of the fire fighting apparatus 6 to discharge seawater, the other dual fuel engine 3B propels the fire pump 11 to drive the ship with the reaction force of the drive load of the fire pump 11. Fire extinguishing activities can be carried out by preventing 1 from retreating.

In the first marine propulsion device 20A on the port side, the propulsion device 5A is installed on the propulsion shaft 13A provided in the dual fuel engine 3A via the first clutch 9A as the main clutch. The first clutch 9A is a slip clutch, and the load transmission coefficient can be freely changed and switched in the range of 100% to 0% of slip. The propulsion shaft 13A is connected to a propulsion device 5A having a propeller 5a.
A propulsion device side output sensor 14A is installed between the dual fuel engine 3A and the first clutch 9A. A rotation speed sensor 15A for detecting the rotation speed of the propulsion shaft 13A is installed between the dual fuel engine 3A and the propulsion device side output sensor 14A. The propulsion device side output sensor 14A is a torque sensor that detects torque, and the output can be calculated from the product of the rotation speed and torque measured by the rotation speed sensor 15A. The output sensor 14A on the propulsion device side may detect both the rotational speed and the torque.

A fire pump 11 of the fire fighting apparatus 6 is connected to a drive shaft 17 provided on the opposite side of the propulsion device 5A with respect to the dual fuel engine 3A, and a second fire pump 11 is connected to the dual fuel engine 3A side of the fire pump 11. The clutch 18 is attached. The second clutch 18 is a PTO (Power take-off) clutch.
A work device side output sensor 19 is installed between the second clutch 18 and the dual fuel engine 3A. Like the propulsion device side output sensor 14A, the work device side output sensor 19 is also a torque sensor that detects torque, and the output can be calculated by the product of the rotation speed and torque measured by the rotation speed sensor 15A. The output sensor 19 on the working device side may detect both the rotational speed and the torque.

Each of these configurations of the first marine propulsion device 20A on the port side is electrically connected to the control device 22. Then, when driving the propulsion device 5A, the control device 22 closes the first clutch 9A and opens the second clutch 18 on the fire fighting apparatus 6 side, and when driving the fire fighting apparatus 6, the first clutch 9A is opened. The clutch 9A is opened and the second clutch 18 on the fire fighting apparatus 6 side is closed. Further, when driving the propulsion device 5A or the fire fighting apparatus 6, the output value of the dual fuel engine 3A measured by the rotation speed sensor 15A and the propulsion device side output sensor 14A or the work device side output sensor 19 by the control device 22. Controls the operation of the dual fuel engine 3A based on.

In the starboard side second marine propulsion device 20B shown in FIG. 2, a propulsion device 5B is installed on the propulsion shaft 13B provided on the dual fuel engine 3B via a third clutch 9B as a main clutch. The first clutch 9B is a slip clutch similar to the first clutch 9A, and can be switched by changing the load transmission coefficient. The propulsion shaft 13B is connected to a propulsion device 5B having a propeller 5b.
A propulsion device side output sensor 14B is installed between the dual fuel engine 3B and the third clutch 9B. A rotation speed sensor 15B is installed between the dual fuel engine 3B and the propulsion device side output sensor 14B. The propulsion device side output sensor 14B is a torque sensor that detects torque, and the output can be calculated by the product of the rotation speed and torque measured by the rotation speed sensor 15B. The output sensor 14B on the propulsion device side may detect both the rotational speed and the torque.

Each of these configurations of the starboard side second marine propulsion device 20B is electrically connected to the control device 22 in the same manner as the first marine propulsion device 20A. When driving the propulsion device 5B, the control device 22 closes the third clutch 9B. Then, the control device 22 controls the operation of the dual fuel engine 3B based on the output value of the dual fuel engine 3B measured by the rotation speed sensor 15B and the propulsion device side output sensor 14B.

Next, the configuration and function of the dual fuel engine 3 will be described with reference to FIGS. 3, 4A, and 4B, for example, as a 4-stroke engine.
The marine dual fuel engine (hereinafter, may be simply referred to as an engine) 3 shown in FIGS. 3, 4A and 4B can be switched between diesel mode and gas mode during operation. The dual fuel engine 3 shown in FIG. 3 is provided with a mechanism of a crankshaft 24 as propulsion shafts 13A and 13B connected to propellers 5a and 5b, and the crankshaft 24 is connected to a piston 26 installed in a cylinder block 25. Has been done. The combustion chamber 28 is formed by the piston 26 and the engine head 27 provided in the cylinder block 25.

The combustion chamber 28 is sealed by an intake valve 29 and an exhaust valve 30 mounted on the engine head 27 and a fuel injection valve 31 used in the diesel mode. The engine head 27 is provided with a micropilot oil injection valve 32 used in the gas mode. A fuel injection pump 33 is connected to the fuel injection valve 31. An intake pipe 34 is connected to the intake port where the intake valve 29 of the engine head 27 is installed, and an exhaust pipe 35 is installed at the exhaust port where the exhaust valve 30 is installed. A fuel gas supply valve 36 composed of a solenoid valve for controlling gas injection is installed in the intake pipe 34, and an air cooler 37 and a supercharger 38 communicating with the exhaust pipe 35 are installed on the upstream side thereof.

As shown in FIGS. 4A and 4B, the dual fuel engine 3 according to the present embodiment can be operated by switching between the diesel mode and the gas mode. In the diesel mode shown in FIG. 4A, for example, heavy oil A or the like is supplied as fuel oil from a fuel tank (not shown) to the fuel injection pump 33, and is mechanically injected from the fuel injection valve 31 into the compressed air in the combustion chamber 28 to ignite. Burn.

In the gas mode shown in FIG. 4B, a fuel gas such as natural gas is supplied to the intake pipe 34 by the fuel gas supply valve 36, premixed with the air flow, and the air-fuel mixture is supplied into the combustion chamber 28 to compress the air-fuel mixture. Ignition is performed by the ignition device in the state. In this example, pilot fuel is injected from the micro pilot oil injection valve 32 to ignite and burn. The micropilot oil injection valve 32 is electronically controlled, for example, and injects a small amount of pilot fuel as a powerful ignition source. The fuel gas supply valve 36 is a solenoid valve capable of forming a large opening with a slight stroke and allowing a large amount of gas to flow in a short time.

The gas mode uses an operation mode in which only gas fuel (gas fuel) is used as fuel to ignite with a spark plug, and a small amount of liquid fuel (pilot oil) is injected to ignite the gas fuel that occupies most of the heat source. It includes both driving styles. In the latter operation mode, the ratio of the liquid fuel to the total fuel is usually about 1% to 10% of the total calorific value in comparison with the calorific value of the rated output. From the viewpoint of achieving environmental regulations for exhaust gas, it is desirable that it is 3% or less.
In the diesel mode, the load is mainly applied when the engine is started and stopped, and when the modes of the first clutches 9A and 9B and the second clutch 18 are switched between the normal operation mode and the firefighting mode. It is an operation mode that is used during fluctuations and operates using only liquid fuel as fuel.

The engine 3 is started in a diesel mode in which liquid fuel is injected into the combustion chamber 28 from the fuel injection valve 31. After confirming that the gas pressure equal to or higher than the reference value is supplied to the engine 3, gas fuel is supplied to the intake pipe 34 by the fuel gas supply valve 36, mixed with air, and then flowed into the combustion chamber 28. , Operate in gas mode to burn gas fuel.
When stopping, change to diesel mode again and then stop. Diesel mode and gas mode can be changed except when starting and stopping.

During steady operation, the engine 3 is theoretically operated in the gas mode along the marine cube root characteristic line in relation to the rotational speed and the output. The marine cube root characteristic refers to the characteristic of the marine main engine (engine 3) whose output is proportional to the cube of the rotational speed in a ship using a fixed pitch propeller 5a. In addition to steady operation, when the ship is operated in stormy weather or when the ship is maneuvered such as a rapid change of course, the output is required to exceed the normal operating range, which greatly exceeds the cubed characteristics of the ship, and in gas mode. Since the output may be insufficient and the operation may be difficult, the liquid fuel is temporarily supplied into the combustion chamber 28 and the operation is performed together with the gaseous fuel.

In the operation system of the ship 1 according to the present embodiment, in order to comply with exhaust gas regulations, basically, normal operation using the propulsion device 5 (normal operation mode) and fire extinguishing work using the firefighting apparatus 6 (firefighting mode) are performed in gas mode. Do it with. In this case, it is difficult to obtain an accurate supply amount of gas fuel in the gas engine, and the magnitude of the output is unknown. However, the first marine propulsion device 20A and the second marine propulsion device 20B work with the propulsion device side output sensors 14A and 14B. An output sensor 19 on the device side is provided to detect the magnitude of the output in a timely manner. It is preferable to use an axial horsepower meter as the propulsion device side output sensors 14A and 14B and the work device side output sensor 19.

Further, in the load drive by the gas mode, since the load fluctuates greatly when the normal operation mode and the firefighting mode are mutually shifted, the gas mode is temporarily shifted to the diesel mode. As a result, it is possible to quickly respond to load fluctuations due to opening / closing switching of the first clutch 9A, the third clutch 9B, and the second clutch 18. Therefore, the control device 22 is provided with a diesel mode transition means 63 that detects an instruction signal for transition to the firefighting mode and temporarily shifts from the gas mode to the diesel mode. Similarly, a gas mode transition means 64 for shifting from the diesel mode to the gas mode after the load fluctuation due to the opening / closing switching of the first clutch 9A, the third clutch 9B, and the second clutch 18 has settled down is provided.
If the load fluctuation at the time of transition from the propulsion mode to the firefighting mode is relatively small, the firefighting mode may be shifted to the firefighting mode without shifting to the diesel mode.

In the power system of the ship 1 according to the present embodiment, the total of the output measurement value by the propulsion device side output sensor 14A of the first marine propulsion device 20A and the output measurement value by the work device side output sensor 19 is taken. The engine 3A may be controlled by obtaining a more accurate output value of the engine 3A.
For example, in the state where the first marine propulsion device 20A is being driven, most of the output of the engine 3A is measured by the propulsion device side output sensor 14A, but the working device side output sensor 19 also has a certain output value. Count. This is because a certain amount of mechanical loss remains on the firefighting apparatus 6 side even when the second clutch 18 on the firefighting apparatus 6 side is opened. The same applies when the fire pump 11 of the fire fighting apparatus 6 is driven by opening the first clutch 9A, and the output sensor 19 on the work device side also counts a certain amount of output value.
Therefore, a more accurate output value of the engine 3A can be obtained by totaling the output values of the propulsion device side output sensor 14A and the working device side output sensor 19.

The dual fuel engine 3 according to the present embodiment includes a gas engine system that controls the output when the load increases in the gas mode. The structure of this gas engine system will be described.
In FIG. 3, a rotation speed sensor 15 (15A, 15B) and a propulsion device side output sensor 14 (14A, 14B) are attached to the crankshaft 24, and the rotation speed sensor 15 has a rotation speed (rotation) of the crankshaft 24. The number) is measured, and the engine torque is measured by the propulsion device side output sensor 14. As the propulsion device side output sensor 14, for example, a strain sensor that detects the torque applied to the shaft by strain can be used. The measurement data measured by the rotation speed sensor 15 and the propulsion device side output sensor 14 are signal-output to the control device 22 that controls the engine 3, respectively.

The control device 22 detects the operating state of the engine 3 based on signals from the rotation speed sensor 15 and the propulsion device side output sensor 14. That is, the rotation speed (rotation speed) of the crankshaft 24 measured by the rotation speed sensor 15 is n, the torque measured by the output sensor 14 on the propulsion device side is T, and the engines are expressed by the following equations (1) and (2). The output (load) A of 3 is calculated. However, Lt is the rated output of the engine 3.
Output Lo = 2πTn / 60 (1)
Output (load) A = Lo / Lt × 100 (2)

As a method of obtaining the output (load) of the engine 3, a method of estimating from information on the fuel supply amount and other information on the operating state of the engine 3 and a method of propulsion to the power transmission system of the propulsion shaft 13 (13A, 13B) of the engine 3 There is a method in which the output sensor 14 on the device side is provided and the torque is actually measured to obtain the output. In a gas fuel engine, since the gas used as fuel is an elastic body, it is relatively difficult to obtain an accurate fuel supply amount as compared with liquid fuel. Therefore, it is preferable to calculate the output by actually measuring the torque with the propulsion device side output sensor 14.
When the rotation speed n is constant, the output A and the torque measurement value T have a direct proportional relationship. Under the condition that the rotation speed n is constant, it is desirable to set the advance angle of the closing timing of the intake valve 29 at a larger rate as the output A is larger, that is, the torque data T is larger.

In the control device 22, the first map 40 for determining the first electric signal of the intake valve opening / closing timing and the second map 41 for determining the second electric signal from the first electric signal and the opening / closing timing are stored. There is. In the control device 22, the above equations (1) and (2) are used based on the rotation speed data n and the torque data T corresponding to the output A of the engine 3 measured by the rotation speed sensor 15 and the propulsion device side output sensor 14. The output A of the engine 3 is calculated. The first electric signal corresponding to the opening / closing timing of the intake valve 29 is selected on the first map 40 by the rotation speed n and the output A. Based on this first electric signal, the opening / closing timing of the intake valve 29 corresponding to the first electric signal is determined on the second map 41.

The second electric signal of the opening / closing timing set by the control device 22 is transmitted to the electropneumatic converter 42, and the opening / closing timing signal is converted into air pressure by the electropneumatic converter 42. This air pressure is sent to the actuator 43 to control the drive of the variable intake valve timing mechanism 44. Air pressures P1 and P2 for driving and control are supplied to the actuator 43 from the first decompression regulator 45 and the electropneumatic converter 42.

The air pressure supplied to the actuator 43 is compressed by the air compressor 46 and stored in the air tank 47. The air pressure in the air tank 47 is reduced to a required pressure by the first decompression regulator 45. The pressure at this time is adjusted by changing the valve opening degree of the first decompression regulator 45, and is supplied to the actuator 43 as the driving air pressure P1. When the pressure P1 measured by the pressure gauge 48 is equal to or less than the specified value, the engine 3 cannot be started.

The air pressure for driving the electropneumatic converter 42 is further reduced by the first decompression regulator 45 to the second decompression regulator 49 and supplied. The electro-pneumatic converter 42 supplies the air pressure corresponding to the second electric signal of the input opening / closing timing to the actuator 43 as the air pressure P2 for adjusting the operation of the actuator 43. Based on these air pressures P1 and P2, the rod 43a of the actuator 43 is operated to operate the variable intake valve timing mechanism 44.

The actuator 43 is, for example, a known P cylinder (cylinder with a position), and controls the advance / retreat of the rod 43a based on the pressures P1 and P2 input from the first decompression regulator 45 and the electropneumatic converter 42. By changing the moving length of the rod 43a of the actuator 43, the drive of the variable intake valve timing mechanism 44 is controlled to advance (advance) or delay (delay) the closing timing of the intake valve 29 from the suction bottom dead center. By doing so, the compression ratio is lowered for control.

Since the time between the valve opening timing and the valve closing timing of the intake valve 29 does not change, when the valve opening timing advances from the suction bottom dead center, the valve closing timing also advances by the same time from the suction top dead center. Moreover, in the present embodiment, knocking is suppressed and the load increase time is shortened by changing the timing of valve opening and valve closing according to the output of the engine 3. The opening / closing timing of the intake valve 29 is set by the first map 40 and the second map 41 in the control device 22 based on the output A and the rotation speed n of the engine 3, and the intake valve 29 is set by the actuator 43 and the variable intake valve timing mechanism 44. The timing of valve opening and closing is adjusted so that knocking can be suppressed.

The configuration of the variable intake valve timing mechanism 44 is conventionally known. That is, in the variable intake valve timing mechanism 44, for example, a link shaft whose rotation angle range is set by the moving length of the rod 43a of the actuator 43 and a cam shaft provided with an eccentric cam are arranged in parallel. An exhaust swing arm is connected to the link shaft, and an intake swing arm is connected to a tappet shaft provided at an eccentric position of the link shaft. An intake valve 29 is connected to the intake swing arm, and an exhaust valve 30 is connected to the exhaust swing arm.

The distance between the cam shaft and the intake swing arm changes depending on the rotation angle of the tappet shaft according to the rotation of the link shaft, and the timing at which the eccentric cam of the cam shaft starts to hit changes. This makes it possible to change the valve closing timing to advance (or retard). The farther the distance from the tappet shaft to the center of the cam shaft is, the earlier the closing timing of the intake valve 29 becomes. The rotation angle of the tappet shaft is changed by the moving length of the rod 43a of the actuator 43. The moving length of the rod 43a is arbitrarily changed by the pressures P1 and P2 of the control air supplied to the actuator 43.
The size of the advance angle, which is the closing / opening timing of the intake valve 29, is determined by the timing at which the eccentric cam of the camshaft starts to hit the intake swing arm connected to the tappet shaft of the link shaft.

As the tappet shaft rotating device in the variable intake valve timing mechanism 44, a servomotor (not shown) may be used instead of the actuator 43. In this case, the servomotor is made to input the opening / closing timing signal transmitted from the second map 41 of the control device 22. The servomotor can change the opening / closing timing of the intake valve 29 by rotating the link shaft by an amount corresponding to the received signal and turning the tappet shaft so as to approach and separate the camshaft. When a servomotor is used, it is not necessary to configure the actuator 43 and the first decompression regulator 45 to the pressure gauge 50. Further, the servomotor is driven by the controller instead of the electropneumatic converter 42.

Further, a gas fuel supply mechanism to the fuel gas supply valve 36 that controls gas injection to the intake pipe 34 will be described. In FIG. 3, gas fuel is supplied to the gas vaporizer 53 from the LNG gas tank 52 in which gas fuel such as natural gas is stored, and the gas pressure is further reduced to a required gas pressure by the gas regulator 54.
This gas pressure is displayed on the fuel gas pressure gauge 55, adjusted by changing the valve opening degree of the gas regulator 54, and is supplied from the fuel gas supply valve 36 into the intake pipe 34 as gas fuel for combustion. In the intake pipe 34, the gas fuel and the supercharged air cooled by the air cooler 37 are mixed and supplied to the combustion chamber 28. When the load is increased, the amount of gas fuel supplied is increased by the operation of the fuel gas supply valve 36.

The second electric signal of the opening / closing timing set by the control device 22 is transmitted to the fuel gas supply valve 36 via the gas governor 57 separately from the electropneumatic converter 42. The gas governor 57 controls the speed control (governor control) of the supply amount of gas fuel in the gas mode. Moreover, the gas governor 57 controls the valve opening timing for opening the fuel gas supply valve 36 and supplying the gas fuel into the intake pipe 34 so as to advance according to the advance angle of the closing timing of the intake valve 29. The gas regulator 54 that adjusts the gas pressure and the gas governor 57 that advances the opening timing of the fuel gas supply valve 36 and controls the speed control are included in the fuel gas supply valve timing mechanism 60.
The gas governor 57 may be installed outside the control device 22. The fuel gas supply valve timing mechanism 60 may receive the second electric signal from the second map 41 and advance the valve opening timing of the fuel gas supply valve 36 according to the advance angle of the closing timing of the intake valve 29. I hope I can.

Further, when shifting from the normal operation mode to the firefighting mode while operating the ship 1 in the gas mode, and when shifting from the firefighting mode to the normal operation mode, the gas mode is temporarily switched to the diesel mode to be in the diesel mode. The opening / closing operation of the first clutch 9A and the second clutch 18 is performed. The operation of the engine 3A in the gas mode is easily affected by load fluctuations, and the disturbance caused by the opening / closing operation of the first clutch 9A and the second clutch 18 may hinder the smooth operation of the engine 3A. Therefore, at the time of transition between the normal operation mode and the firefighting mode, the load is temporarily switched from the gas mode to the diesel mode which is resistant to load fluctuations, and the first clutch 9A and the second clutch 18 are opened and closed to open and close the load. The adverse effect on the engine 3A due to the fluctuation can be suppressed.
When the load from the fire pump 11 is relatively small, the disturbance when closing the second clutch 18 on the side of the fire pump 11 is also relatively small, so this operation can be omitted depending on the conditions. is there.

In the power system of the ship 1 according to the present embodiment, assuming that the normal operation of the ship 1 is performed in the gas mode, when shifting from the normal operation mode by the gas mode to the firefighting mode, there are cases where the load fluctuates suddenly and cases where the load fluctuates. It may be small. Therefore, in the present embodiment, (A) a case of passing through the diesel mode at the time of transition in both directions between normal operation and firefighting is set as the first embodiment, and (B) transition from normal operation to firefighting operation. A case where the gas mode is sometimes left and the diesel mode is passed only at the time of transition from the fire fighting to the normal operation mode will be described separately as a second embodiment.

(A) The procedure in the case of passing through the diesel mode at the time of transition between the normal operation mode and the firefighting mode in the first embodiment will be described with reference to the flowchart shown in FIG.
In this case, it is suitable when the load of the fire pump 11 in the fire device 6 is relatively large.
a) Procedure for switching from normal operation mode to firefighting mode.
During normal mode operation of the dual fuel engines 3A and 3B on the ship 1, the first clutch 9A and the third clutch 9B are closed in the first marine propulsion device 20A and the second marine propulsion device 20B on both sides, and the third clutch 9B is closed. The operation is performed in the gas mode in which the clutch 18 of 2 is opened (S100). The propellers 5a and 5b on both the starboard and starboard sides are driven to propel the ship 1. To switch from this state to the firefighting mode, the rotation speeds of the engines 3A and 3B on both sides are slowed down to idle operation (S101).

Next, the first clutch 9A and the third clutch 9B on both sides are opened. Then, the switching instruction signal to the firefighting mode is output to the control device 22 (S102), and the port first marine propulsion device 20A is switched from the gas mode operation to the diesel mode operation (S103). After that, the third clutch 9B of the starboard second marine propulsion apparatus 20B is closed, and the second clutch 18 of the port firefighting apparatus 6 is closed (S104).
The operation of the engine 3A in the gas mode is easily affected by load fluctuations, and the disturbance caused by the opening / closing operation of the first clutch 9A and the second clutch 18 may hinder the smooth operation of the engine 3A. Therefore, when shifting from the normal operation mode to the firefighting mode, the clutch is operated by temporarily switching to the diesel mode, which is resistant to load fluctuations. In this embodiment, the first clutch 9A and the third clutch 9B are slip clutches, and the operation from closing to opening of the clutch can be gradually performed. Therefore, the operation of opening these clutches remains in the gas mode. Although it is done, it is possible to switch to the diesel mode first and operate in the diesel mode.

Next, the first marine propulsion device 20A on the port side switches from diesel mode to gas mode operation (S105) to switch to firefighting mode (S106). Then, the rotation speeds of the engines 3A and 3B on both sides are increased. Then, in the fire-fighting mode, the fire-fighting pump 11 of the fire-fighting apparatus 6 is driven by the port engine 3A, and the seawater pumped up from the sea is discharged by the water discharge nozzle 6a. At the same time, the starboard engine 3B drives the starboard propeller 5b to propel the ship 1.
Here, the water discharge of the fire pump 11 receives a reaction force in the direction in which the ship 1 retreats, but the reaction force is offset by driving the propulsion device 5B forward by the second marine propulsion device 20B on the starboard side, and the ship 1 cancels out. Stays in the stop position. In this way, fire extinguishing activities are carried out in firefighting mode. The starboard engine 3B is not switched to the fire pump, but the third clutch 9B on the starboard side is also opened and closed together with the port side in order to balance the thrusts on both the left and right sides. The opening / closing operation of the third clutch 9B can be omitted.

b) Procedure for switching from the firefighting mode to the normal operation mode In the flowchart shown in FIG. 6, when the fire extinguishing activity in the firefighting mode is completed (S107), the ship 1 switches from the firefighting mode to the normal operation mode. In that case, the rotation speeds of the engines 3A and 3B on both sides are slowed down to enter the idle operation state (S108). Then, the third clutch 9B of the starboard second marine propulsion device 20B is opened. A switching command to the normal operation mode is output (S109).
When the fire fighting apparatus 6 is switched to the propulsion apparatus 5A in the gas mode, the load may fluctuate abruptly, which may cause misfire or knocking. Therefore, the load fluctuation can be dealt with by temporarily switching to the diesel mode and switching the opening / closing operation of the first clutch 9A and the second clutch 18.

Next, the control device 22 switches the engine 3A of the port first marine propulsion device 20A from gas mode operation to diesel mode operation (S110). Then, the second clutch 18 on the port side is opened, and the first clutch 9A and the third clutch 9B on both the left and right sides are closed (S111). The port first marine propulsion device 20A is switched from diesel mode operation to gas mode operation (S112), and together with the starboard second marine propulsion device 20B, the normal operation mode is set (S113).

The operation of the engine 3A in the gas mode is easily affected by load fluctuations, and the disturbance caused by the opening / closing operation of the first clutch 9A and the second clutch 18 may hinder the smooth operation of the engine 3A. Therefore, when shifting from the firefighting mode to the normal operation mode, the clutch is opened and closed by temporarily switching to the diesel mode, which is resistant to load fluctuations.
Then, the rotation speeds of the engines 3A and 3B of the first and second marine propulsion devices 20A and 20B on both the port and starboard sides are increased, and the propellers 5a and 5b of the propulsion devices 5A and 5B on both the left and right sides are driven to drive the ship 1. By propelling, the normal operation mode is performed.

B) In the second embodiment ship 1, the procedure in the case of shifting to the diesel mode only in one direction will be described with reference to FIG. 7. In this case, it is suitable when the load of the fire pump 11 in the fire device 6 is relatively small. That is, in the second embodiment, the switch from the normal operation mode of the ship 1 to the firefighting mode does not go through the diesel mode, and the transition from the firefighting mode to the normal operation mode goes through the diesel mode.

a) Procedure for switching from normal operation mode to firefighting mode.
In the normal operation mode of the ship 1, the first and second marine propulsion devices 20A and 20B on both the left and right sides are closed, the first clutch 9A and the third clutch 9B are closed, and the second clutch 18 on the port side is opened. , The engines 3A and 3B on both starboard and starboard sides are operated in gas mode (S200).
From this state, the rotation speeds of the engines 3A and 3B of the first and second marine propulsion devices 20A and 20B on both sides are slowed down to the idle operation state (S201). Then, the first clutch 9A and the third clutch 9B of the first and second marine propulsion devices 20A and 20B on both the starboard and starboard sides are opened.

Next, a command for switching from the normal operation mode to the firefighting mode is output to the control device 22 (S202). In this case, since the load on the fire pump 11 (or other working device driven by the engine 3A) is small, the control device 22 causes the engine 3A of the first marine propulsion device 20A on the left side to operate in the gas mode without switching to the diesel mode operation. Keep driving.
The third clutch 9B of the starboard second marine propulsion device 20B is closed, and the port second clutch 18 is closed (S203). In this way, in the gas mode, the normal operation mode is switched to the firefighting mode (S204). Then, the rotation speeds of the engines 3A and 3B on both sides are increased.

In the fire-fighting mode, the engine 3A of the first marine propulsion device 20A on the port side drives the fire-fighting pump 11 of the fire-fighting apparatus 6 to discharge seawater. On the other hand, in the starboard second marine propulsion device 20B, the engine 3B drives the propeller 5b of the starboard propulsion device 5B to propel the ship 1.
The reaction force is received by the water discharge of the fire pump 11, and the load is applied in the direction in which the ship 1 retreats, but the reaction force is offset by the second marine propulsion device 20B on the starboard side to advance the propulsion device 5B, and the ship 1 is in the stop position. Stay in. In this way, fire extinguishing activities are carried out in firefighting mode.

b) Procedure for switching from firefighting mode to normal operation mode.
The operation method in this state is the same as that shown in A) b) described above, and will be described with reference to the flowchart shown in FIG.
In ship 1, in the firefighting mode (S107), the first clutch 9A in the port first marine propulsion device 20A is opened, and the second clutch 18 is closed. Further, the third clutch 9B in the starboard second marine propulsion device 20B is closed. In this state, the port engine 3A drives the fire pump 11 of the fire fighting apparatus 6 to discharge water. The starboard engine 3B drives the propeller 5b in the second marine propulsion device 20B to propel the ship 1.
When switching the firefighting mode, the rotation speeds of the engines 3A and 3B in the first and second marine propulsion devices 20A and 20B on both sides are slowed down to idle operation (S108).

Next, the third clutch 9B on the starboard side is opened. Then, a command for switching the ship 1 from the firefighting mode to the normal operation mode is output to the control device 22 (S109). As a result, in the first marine propulsion device 20A on the port side, the engine 3A is switched from gas mode operation to diesel mode operation (S110).
In the port side first marine propulsion device 20A, the second clutch 18 is opened. In the first and second marine propulsion devices 20A and 20B on both starboard sides, the first clutch 9A and the third clutch 9B are closed (S111). Then, the port first marine propulsion device 20A is switched from diesel mode operation to gas mode operation (S112).
Next, the rotation speeds of the engines 3A and 3B in the first and second marine propulsion devices 20A and 20B on both the starboard and starboard sides are increased. Then, in the normal operation mode, the propellers 5a and 5b of the propulsion devices 5A and 5B on both sides are driven to propel the ship 1 (S113).
In this way, the operation of switching between the gas mode and the diesel mode is controlled when the load of the firefighting apparatus 6 is large and small.

C) Auto slowdown control Output values by the propulsion device side output sensors 14A and 14B and the work device side output sensor 19 of the dual fuel engines 3A and 3B in the normal operation state of the ship 1 and the work device drive state such as the fire mode. It is necessary to prevent overloading, and the ship class rules are set by each ship class engine. For example, when the output measurement values of the propulsion device side output sensors 14A and 14B of the engines 3A and 3B reach 80% or more, the control device 22 issues an alarm, and after reaching 100% or more, the output drops to 95% for 30 seconds. Otherwise, it is considered that 100% condition will continue. In that case, for example, according to the ship class rules stipulated by ABS (USA), if the output of the engine 3A is 95% or more for 30 seconds, the rotation speed of the engines 3A and 3B unless the override operation button is pressed within 5 seconds thereafter. Is forced to slow down. Assuming that the preset slowdown value is set to the predetermined value Xmin- ¹ , the engines 3A and 3B are forcibly slowed down until the rotation speed reaches Xmin- ¹ .

Generally, on the firefighting apparatus 6 side, the output measurement value of the work device side output sensor 19 is small and does not reach 100%, but on the propulsion apparatus 5A and 5B sides, unreasonable maneuvering and propulsion are performed to avoid danger when the vessel 1 is operated. There was a risk that excessive output would be applied to the engines 3A and 3B. In this case, the engine 3 is protected by auto slowdown control.

Next, an example of auto slowdown control based on this ship class rule will be described with reference to FIG.
In the normal operation mode (S300), during propulsion of the propulsion devices 5A and 5B, for example, for danger avoidance, the output measurement value by the propulsion device side output sensors 14A and 14B of the dual fuel engines 3A and 3B is a predetermined upper limit value. (Reference value) may be exceeded (S301). In this case, the rotation speed is slowed down at a predetermined rate so that the measured output value of the engine 3A becomes equal to or less than the upper limit value (S302).
The upper limit of this auto slowdown control is the output value of only the engine 3A of the first marine propulsion device 20A on the port side provided with the firefighting apparatus 6, or only the engine 3B of the second marine propulsion device 20B without a firefighting pump. It may be set by the output value. Alternatively, the total output value of both the port and starboard engines 3A and 3B may be set. Which one to select is appropriately set as needed.

According to the power system of the ship 1 according to the present embodiment, the dual fuel engines 3A and 3B that can be operated by switching between the gas mode and the diesel mode are used. In the gas mode, it is necessary to control the ratio of the amount of fuel gas and air more accurately in order to prevent knocking and misfire, and the output of the engines 3A and 3B is measured in real time by the propulsion device side output sensors 14A and 14B. However, it is effective to control the engines 3A and 3B accordingly.

As described above, according to the power system of the ship according to the present embodiment, the propulsion device side output sensors 14A and 14B on the propulsion devices 5A and 5B side, the work device side output sensor 19, the engines 3A, 3B and the first clutch 9A are used. , 9B and between the engine 3A and the second clutch 18, so that the actual output of the engine 3A can be measured more accurately including the loss due to the resistance of the transmission system and the clutch. Moreover, even when the first clutch 9A and the second clutch 18 are open, the output can be measured including the resistance thereof.
Therefore, even in the gas engine mode using gas fuel, the engines 3A and 3B can be operated by detecting the output measurement values of the engines 3A and 3B by the propulsion device side output sensors 14A and 14B and the working device side output sensor 19. It can be strictly controlled.

In addition, when the ship 1 is operating in the gas mode and the propulsion device 5A is driven and the fire pump 11 is driven in both directions, the gas mode is temporarily switched to the diesel mode, which is resistant to load fluctuations. By switching the opening and closing of the first clutch 9A and the second clutch 18, the disturbance caused by the opening and closing of the first clutch 9A and the second clutch 18 is suppressed without being affected by the load fluctuation, and the engine Smooth operation of 3A can be performed.
If the load from the fire pump is relatively small, the disturbance when closing the second clutch 18 on the fire pump 11 side is also relatively small, so the shift to the fire device 6 may be omitted depending on the conditions. It is possible.

Further, in the case of auto slowdown control, when the output measurement value of the propulsion device side output sensors 14A and 14B or the output measurement value of the work device side output sensor 19 exceeds the specified upper limit value, the rotation of both engines 3A and 3B Knocking, misfire, etc. can be prevented by forcibly reducing the speed.

Further, in the dual fuel engine 3A on the left side, even when the second clutch 18 on the fire fighting apparatus 6 side is opened or the first clutch 9A on the propulsion device 5A side is opened, the fire pump 11 side and the propulsion device 5A Some mechanical loss remains on the side. Therefore, by taking the sum of the output value by the propulsion device side output sensor 14A and the output value by the work device side output sensor 19 on the fire fighting apparatus 6 side, a more accurate output value of the engine 3A can be obtained and the engine 3A can be controlled. It can be done with high accuracy.
Further, auto slowdown control for lowering the rotation speed of the engine 3A can be performed based on the total of the output values of the propulsion device side output sensor 14A and the work device side output sensor 19.

Further, according to the ship 1 having the fire fighting apparatus 6 according to the present embodiment, a total of two marine propulsion devices 20A including the engine 3A and a second marine propulsion device 20B including the engine 3B are provided in parallel on both the left and right sides. When one dual fuel engine 3A drives the fire pump 11 of the fire fighting apparatus 6 to discharge water, the other dual fuel engine 3B propels the ship 1 to move backward due to the reaction force of the drive load of the fire pump 11. You can prevent this and extinguish the fire.

The power system of the ship 1 according to the present invention is not limited to the above-described embodiment, and can be appropriately changed or replaced without departing from the spirit of the present invention. Hereinafter, modifications of the present invention and the like will be described, but the same or similar parts and members described in the above-described embodiment will be described by using the same reference numerals.

In the embodiment of the present invention, the first marine propulsion device 20A and the second marine propulsion device 20B are arranged on the port and starboard sides of the ship 1, and the first marine propulsion device 20A is provided with the fire fighting apparatus 6 as a working device in a gas mode. The power system of ship 1 capable of selectively operating one of the starboard mode and the diesel mode was used.
However, the above-mentioned invention merely shows one embodiment of the present invention, and the present invention is not limited to such a configuration. In the present invention, the concept of the invention can be applied as long as the output of the dual fuel engine 3 is used not only for driving the propulsion device 5 but also for driving the working device.

For example, the working device is not limited to the fire-fighting apparatus 6 provided with the fire-fighting pump 11 described above, but the ship 1 is driven by a pump for other purposes, a cargo handling machine such as a crane, or a main engine for propelling the ship 1. It is possible to adopt a work device including various machines mounted on the vehicle.

Further, the power system of the ship 1 according to the present invention may control the dual fuel engine 3A by one or the total of the output measurement value by the propulsion device side output sensor 14A and the output measurement value by the work device side output sensor 19. Good.
Alternatively, the dual fuel engine 3A may be controlled by the output measurement value of the propulsion device side output sensor 14A with the first clutch 9A closed, or the working device may be controlled with the second clutch 18 closed. The dual fuel engine 3A may be controlled by the output measured value by the side output sensor 19.

Further, the power system of the ship 1 according to the present invention is not limited to a configuration in which two propulsion devices 5A and 5B are provided on the port side and the starboard side, and a work device such as a fire fighting apparatus 6 is provided on one of them. For example, one propulsion device 5 may be provided, a drive shaft 17 may be provided on the dual fuel engine 3, and a work device such as a fire fighting apparatus 6 may be installed. Alternatively, a work device such as a fire fighting apparatus may be attached to the engine 3 provided with three or more propulsion devices 5 and one or two or more propulsion devices 5.

In the present invention, a propulsion device is connected to an engine that can use at least gaseous fuel as a main fuel via a first clutch, and a work device such as a fire fighting device is connected to the engine via a second clutch. A propulsion device side output sensor is provided between the clutch of No. 1 and a work device side output sensor is provided between the engine and the second clutch. The first clutch is closed and the second clutch is opened to drive the propulsion device, the first clutch is opened and the second clutch is closed to drive the working device. Moreover, by measuring the output of the engine mainly composed of gaseous fuel with the propulsion device side output sensor and the work device side output sensor and controlling the engine drive, a ship power system that can drive and control the work device in gas mode provide.

1 Ship 3, 3A, 3B Dual Fuel Engine (Engine)
5, 5A, 5B Propulsion device 6 Fire device 9A 1st clutch 9B 3rd clutch 11 Fire pump 13A, 13B Propeller shaft 14, 14A, 14B Propulsion side output sensor
15, 15A, 15B Rotational speed sensor 17 Drive shaft 18 Second clutch 19 Working device side output sensor 22 Control device

Claims (10)

Engines that can use gaseous fuel as the main fuel,
A propulsion device that is connected to the engine via a first clutch and driven.
A propulsion device side output sensor provided between the engine and the first clutch,
A working device connected to the engine via a second clutch and driven,
A work device side output sensor provided between the engine and the second clutch,
A ship power system characterized by being equipped with. The ship power system according to claim 1, wherein the work device is a fire fighting apparatus for discharging water. A control device is provided which closes the first clutch and opens the second clutch to drive the propulsion device, opens the first clutch and closes the second clutch to drive the working device. The ship power system according to claim 1 or 2. The power of the ship according to any one of claims 1 to 3, wherein the engine is controlled by the sum of the output measurement value by the propulsion device side output sensor and the output measurement value by the work device side output sensor. system. From claim 1, the control for lowering the rotation speed of the engine is performed when the output measurement value by the propulsion device side output sensor and / or the output measurement value by the work device side output sensor exceeds the upper limit value. 4. The ship power system according to any one of paragraphs 4. The ship power system according to any one of claims 1 to 5, wherein the propulsion device side output sensor and the work device side output sensor are torque sensors that measure the torque actually applied to the propulsion shaft of the engine. .. When shifting from the state of driving the propulsion device to the state of driving the working device during operation in the operation mode using the gaseous fuel as the main fuel.
The operation mode using the gas fuel as the main fuel is temporarily switched to the operation mode using the liquid fuel as the main fuel to operate at least one of the first clutch or the second clutch, and then the liquid. The power system for a ship according to any one of claims 1 to 6, wherein the operation mode using the fuel as the main fuel is returned to the operation mode using the gas fuel as the main fuel. When shifting from the state of driving the working device to the state of driving the propulsion device during operation in the operation mode using the gaseous fuel as the main fuel.
The operation mode using the gas fuel as the main fuel is temporarily switched to the operation mode using the liquid fuel as the main fuel, and at least one of the second clutch or the first clutch is operated, and then the liquid. The ship power system according to any one of claims 1 to 7, wherein the operation mode using fuel as the main fuel is returned to the operation mode using the gas fuel as the main fuel. The control device is
Diesel mode transition means for shifting from a gas mode using gas fuel as a main fuel to a diesel mode using liquid fuel as a main fuel in order to open one of the first clutch and the second clutch and close the other. When,
A gas mode transition means for shifting from the diesel mode to the gas mode after the operation of opening one of the first clutch and the second clutch and closing the other is completed.
The ship power system according to claim 3. It is a power system for ships equipped with multiple engines that can use gaseous fuel as the main fuel.
On the engine side of 1,
A propulsion device that is connected to the engine via a first clutch and driven.
A propulsion device side output sensor provided between the engine and the first clutch,
A working device connected to the engine via a second clutch and driven,
A work device side output sensor provided between the engine and the second clutch,
A control device that closes the first clutch and opens the second clutch to drive the propulsion device, opens the first clutch and closes the second clutch to drive the working device. Prepare,
On the other engine side,
With other propulsion devices driven by being connected to the other engine via a third clutch,
It is provided with another propulsion device side output sensor provided between the other engine and the third clutch.
A ship power system characterized in that the control device closes the third clutch to drive the other propulsion device.

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