Ship speed control system and ship equipped with the system

Abstract

Provided are a ship speed control system that automatically performs control so that the ship speed of a ship that is greatly affected by external disturbances remains constant, and a ship equipped with said system. To achieve this purpose, one aspect of the present disclosure is a ship speed control system (100) for controlling the sailing speed of a ship (10), the system comprising: a main propulsion device (11) of the ship, including an internal combustion engine (12) and a propeller (13) driven by the internal combustion engine (12); an auxiliary propulsion device (14) that assists the propulsive force of the ship (10) using natural energy; a ship speed detection device (20) that detects the sailing speed of the ship (10); a main engine controller (30) that controls the main propulsion device (11); and a control device (40) that determines whether the sailing speed of the ship (10) is within a prescribed range including a preset ship speed V0, and, if the sailing speed is not within the prescribed range, transmits a signal for changing the rotation speed N of the propeller (13) to the main engine controller (30) on the basis of the result of a calculation based on a prescribed propeller rotation speed during constant ship speed control.

Description

[Technical Field]

[0001] This invention relates to a ship speed control system and a ship equipped with the system. [Background technology]

[0002] In typical vessels equipped solely with an engine as a propulsion system, the ship's speed is changed by adjusting the engine's rotational speed. In situations where external disturbances such as wind and sea conditions are minor, the change in ship's speed is slow. However, in situations where external disturbances cause a large change in ship's speed, the crew usually manually adjusts the engine's rotational speed to achieve the desired speed.

[0003] On the other hand, in ships equipped not only with engines but also with devices that assist the ship's propulsion using natural energy such as wind (hereinafter referred to as auxiliary propulsion devices), the effects of external disturbances become relatively larger, and consequently, changes in ship speed tend to be larger. When the effects of external disturbances are large, it becomes necessary to adjust the engine speed in accordance with the changes in ship speed, but in reality, frequently changing the engine speed manually is cumbersome and impractical.

[0004] Furthermore, maintaining a constant speed within a given range when a vessel is under the influence of external disturbances is advantageous in terms of ensuring the vessel operates on schedule and reducing fuel consumption by achieving efficient navigation without waste. Maintaining a constant speed is especially important when operating large vessels such as bulk carriers that transport bulk cargo in their holds. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 2015-44588 [Overview of the project] [Problems that the invention aims to solve]

[0006] However, the reality is that no specific technology has been provided to date for maintaining a constant ship speed under the influence of disturbances in ships equipped with auxiliary propulsion systems.

[0007] Therefore, the present invention aims to provide a ship speed control system that automatically controls the ship speed to be constant for ships that are greatly affected by external disturbances, and a ship equipped with the system. [Means for solving the problem]

[0008] One aspect of the present invention is a system for controlling the cruising speed of a ship, The main propulsion system of the vessel, including an internal combustion engine and a propeller driven by the internal combustion engine, An auxiliary propulsion system that uses natural energy to assist the propulsion of a ship, A ship speed detection device that detects the ship's cruising speed, The main engine controller controls the main propulsion system, A control device that determines whether the ship's cruising speed is within a predetermined range including a set ship speed V0, and if it is not within the predetermined range, transmits a signal to the main engine controller to change the propeller rotation speed N based on the result of a calculation based on a predetermined propeller rotation speed during constant ship speed control, It is a ship speed control system equipped with [the following features].

[0009] According to the ship speed control system described above, even when natural energy fluctuates rapidly and the auxiliary propulsion force fluctuates significantly, the ship speed can be automatically controlled to be constant. This allows for efficient navigation without waste, for example, by treating the thrust of the main propulsion system, which consists of an internal combustion engine, as being equivalent to that obtained from the auxiliary propulsion system, thereby reducing fuel consumption and thrust.

[0010] In the ship speed control system as described above, the navigation speed of the ship may be constantly detected by the ship speed detection device during the control by the control device.

[0011] In the ship speed control system as described above, the navigation speed of the ship may be the speed through water or the speed over ground.

[0012] In the ship speed control system as described above, the average ship speed V of the ship within a predetermined measurement time ΔT X is calculated, and it may be determined whether the difference ΔV between the set ship speed V0 and the average ship speed V X is within a predetermined range.

[0013] In the ship speed control system as described above, when the difference ΔV is not within the predetermined range, the increase or decrease process of the rotational speed N of the propeller may be performed.

[0014] In the ship speed control system as described above, the rotational speed N of the propeller may be increased or decreased step by step.

[0015] In the ship speed control system as described above, after the increase or decrease process of the rotational speed N of the propeller is performed, when the ship speed V of the ship has reached the set ship speed V0, the rotational speed N of the propeller may be held.

[0016] In the ship speed control system as described above, after the increase or decrease process of the rotational speed N of the propeller is performed, when the ship speed V of the ship has not reached the set ship speed V0, the process of changing the rotational speed N of the propeller to N±ΔN may be performed.

[0017] In the ship speed control system as described above, ΔN may be calculated based on a calculation formula including the ship speed difference ΔV and a numerical value specific to the propeller as parameters.

[0018] In the ship speed control system as described above, as the calculation formula,

Number

Number

Number

[0019] In the ship speed control system as described above, after the process of changing the rotational speed N of the propeller to N±ΔN, a predetermined interval time T may be provided before the next process of changing to N±ΔN.

[0020] In the ship speed control system as described above, after the predetermined interval time T has elapsed, the average ship speed V of the ship within a predetermined measurement time ΔT X is calculated, and the process of determining whether the difference ΔV between the set ship speed V0 and the average ship speed V X is within a predetermined range may be performed again.

[0021] The auxiliary propulsion device in the ship speed control system as described above may be a sail-running device that receives wind with a sail or kite provided on the hull of the ship.

[0022] The sail or kite of the sail-running device in the ship speed control system as described above may be deformable or detachable so as to be able to change the force received from the wind.

[0023] The sail in the ship speed control system as described above may be made of steel or FRP.

[0024] The ship speed control system as described above may include, in addition to the first auxiliary propulsion device consisting of a sail-running device, a second auxiliary propulsion device that obtains propulsion force by the Magnus effect.

[0025] A ship according to one aspect of the present invention is equipped with the ship speed control system as described above.

[0026] The above-mentioned vessel is, for example, a bulk carrier. [Effects of the Invention]

[0027] According to the present invention, it is possible to provide a ship speed control system that automatically controls the ship speed to be constant for ships that are greatly affected by external disturbances, and a ship equipped with the system. [Brief explanation of the drawing]

[0028] [Figure 1] This is a side view of the starboard side of a vessel in one embodiment of the present invention. [Figure 2] This is a plan view of a ship. [Figure 3] This is a schematic diagram of the ship speed control system configuration. [Figure 4] An example of ship speed control using a ship speed control system is shown. [Figure 5] This graph illustrates an example of ship speed control using a ship speed control system, showing the change in ship speed. [Modes for carrying out the invention]

[0029] Preferred embodiments of the present invention will be described below with reference to the attached drawings.

[0030] The vessel 10 of this embodiment is equipped with a ship speed control system 100 and is configured to be able to navigate under the control of the system. Below, the configuration of the vessel 10 will be described in general terms, and then the ship speed control system 100 of the vessel 10 will be described.

[0031] [Ship] The vessel 10 of this embodiment is equipped with a main engine (main propulsion device) 11, as well as an auxiliary propulsion device 14 that uses natural energy such as wind to assist in propulsion, and is further equipped with a ship speed detection device 20, a main engine controller 30, a control device 40, etc. (see Figure 3, etc.). In the following description, the vessel 10 is described as a bulk carrier, but this is merely a preferred example of the vessel 10, and the size and type of the vessel 10 to which this application applies are not particularly limited.

[0032] The main engine 11 is an engine that functions as the main propulsion device, generating most of the thrust of the vessel 10. In this embodiment, the main engine 11 is a device including an engine 12 and a propeller 13 (see Figures 1 and 3). The engine 12 is composed of a prime mover including an internal combustion engine that generates the force to rotate the propeller 13. The propeller 13 rotates in response to the rotational driving force of the engine 12, causing the vessel 10 to move forward or backward (see Figure 1, etc.).

[0033] The auxiliary propulsion device 14 is a device that assists the propulsion of the vessel 10 by obtaining auxiliary propulsion force using natural energy such as wind. The vessel 10 in this embodiment is equipped with two types of auxiliary propulsion devices 14: a sailing device 15 which is a first auxiliary propulsion device, and a rotating sail 16 which is a second auxiliary propulsion device (see Figures 1 and 2). In this embodiment, a device that uses wind as an auxiliary propulsion device is described, but this is only one example of a manner in which natural energy is used. Although not described in detail in this specification, other examples of manners in which natural energy is used include so-called air lubrication systems that reduce seawater resistance by sending air into the bottom of the ship and letting it accumulate, and so-called kite systems (see Figures 1 and 2) consisting of a kite 18 that receives wind and provides auxiliary propulsion force to the vessel 10.

[0034] The sailing device 15 is a device consisting of a sail 15S provided on the bow portion of the hull, for example, and obtains propulsion by receiving wind. In this embodiment, the sailing device 15 is employed in which the sail 15S is made of steel or FRP (see Figures 1 and 2), but the transport device 15 may also be employed in which the sail 15S is made of other materials, such as cloth or canvas, and the material and structure of the sail 15S are not particularly limited. The sail 15S in this embodiment is substantially semi-cylindrical in shape and is supported in a state in which it can rotate around a support shaft 15A that extends vertically on the hull, and is capable of turning (rotating) to the left and right, and also extending and contracting up and down (see Figure 2, etc.). The sail 15S may be deformable so as to change the force it receives from the wind (for example, the overall height can be changed by shifting up and down a part of the sail 15S which is divided into multiple parts).

[0035] The rotating sails 16 are provided as a second auxiliary propulsion device, for example, in two locations on the hull, and are configured to obtain thrust through the Magnus effect (see Figures 1 and 2). Specifically, these rotating sails 16 consist of cylindrical columnar objects that extend vertically, and generate thrust through the Magnus effect by rotating them around a vertical axis. In this embodiment, the rotating sails 16 are controlled by a control device 17, and operate based on signals transmitted from the control device 17, and their state and condition are monitored by the control device 17 (see Figures 2 and 3). When the control device 17 detects that the rotating sails 16 are in an abnormal state, it transmits a signal (FAILURE ALARM) to the control device 40 to inform it of the abnormality (see Figure 3).

[0036] The ship speed detection device 20 is a device for detecting the ship speed (cruising speed) of the vessel 10. The ship speed detection device 20 can include an electromagnetic log using electromagnetic induction, a Doppler sonar that measures the change in frequency of sound waves when they are emitted from a device on the bottom of the ship and return to the bottom, or a device that uses radio waves from an artificial satellite. In this embodiment, the ship speed detection device 20 uses measuring instruments that measure the ship speed relative to water for purposes such as fuel consumption (indicated by reference numeral 21 in Figure 3), such as a Doppler current meter or an electromagnetic current meter, or measuring instruments that measure the ship speed relative to land for purposes such as navigation route, distance traveled, and speed (indicated by reference numeral 22 in Figure 3), such as a satellite speed log or GPS (see Figure 3). In this embodiment, while the ship speed control system 100 is being controlled by the control device 40, the ship speed detection device 20 constantly detects the ship speed (cruising speed) V of the vessel 10.

[0037] The main engine controller 30 is a device that controls the main engine 11 in response to instruction signals received from the control device 40. In this embodiment, a remotely controllable main engine controller (main engine remote control) 30 is used so that the main engine 11 can be controlled from a distance (see Figure 3). Although not shown in detail, the main engine controller 30 is equipped with a user interface 31 and is configured to allow settings such as the control status and the control range of the rotation speed of the main engine 11.

[0038] The control device 40 determines whether the ship speed detected by the ship speed detection device 20 is within a predetermined range including the set ship speed V0, and transmits a predetermined control signal if it is not within the predetermined range. The control device 40 in this embodiment is composed of a device including a storage device 41 for storing a predetermined program and a computer 42 that executes processing in a predetermined procedure according to the program, for example, an IAS (Integrated Automatic System) (see Figure 3). As will be described in detail later, the control device 40 transmits start / stop signals for constant ship speed control and acceleration / deceleration signals for ship speed V to the main engine controller 30, and receives signals from the main engine controller 30 indicating that acceleration / deceleration is complete, information regarding the current rotational speed of the main engine 11, information that the rotational speed of the main engine 11 cannot be changed, and signals indicating an abnormality of the main engine 11 (FAILURE ALARM) (see Figure 3).

[0039] [Ship speed control system] The ship speed control system 100 is configured to automatically maintain a constant ship speed for a vessel 10 affected by disturbances by variably controlling the rotational speed of the main engine 11's engine 12 and propeller 13 in order to efficiently utilize the thrust obtained by the auxiliary propulsion device 14 and reduce fuel consumption. The ship speed control system 100 of this embodiment is configured as a system consisting of the main engine 11, auxiliary propulsion device 14, ship speed detection device 20, main engine controller 30, and control device 40 as described above (see Figure 3).

[0040] An example of constant ship speed control using the ship speed control system 100 is explained (see Figures 4 and 5).

[0041] [Preparatory procedures for constant ship speed control] First, the rotational speeds of the engine 12 and propeller 13 of the main engine 11 are increased until the ship speed V reaches an arbitrarily set ship speed (corresponding to example 15 knots in Figure 5), within the range in which the ship speed V is subject to constant ship speed control (referred to as the "settable ship speed range" in this specification, and indicated by the symbol VR in Figure 5) (STEP-1). The settable ship speed range VR is a predetermined range of ship speed V that can be controlled when the ship speed V is automatically controlled by the program to keep the ship speed V constant based on a set predetermined ship speed (set ship speed V0) (see Figure 5). Also, the sail 15S is deployed as appropriate during this process.

[0042] When the rotational speed of the engine 12 and propeller 13 reaches the specified speed, an arbitrary set ship speed V0 value (for example, 15 knots) is input to the control device 40 using an input device (not shown) (STEP-2), and constant ship speed control is started (STEP-3). The set ship speed V0 value can be selected and input as either the ship speed relative to the water or the ship speed relative to the ground. Incidentally, the notations "FULL" and "NAV.FULL" in Figure t refer to the output of the main engine 11. Generally, the rotational speed of the propeller 13 and the ship speed increase in the order of "STOP", "DEAD SLOW", "SLOW", "HALF", "FULL", and "NAV.FULL" from the lowest output of the main engine 11. Under normal circumstances, the ship is sailing at "FULL" or "NAV.FULL".

[0043] Furthermore, if ΔN (the difference between the calculated optimal rotational speed derived from the difference in ship speed ΔV), which will be described later, falls within the Bird Range, the rotational speed may be automatically reset to a lower value than the Bird Range (see Figure 5). The Bird Range is set to avoid the risk of the propeller 13 shaft being damaged by excessive torsional vibration stress if the ship operates within the Bird Range for an extended period of time.

[0044] [Constant ship speed control] The average speed V of the vessel 10 during a certain measurement time ΔT [minutes] X The control device 40 calculates the set ship speed V0 and the average ship speed V XCalculate the difference ΔV with respect to it (the threshold value is variable, and the positive / negative of the difference can be set with + / −) (STEP-4). Also, with respect to the rotational speed N of the propeller 13, derive the difference ΔN from the difference ΔV in the ship speed with respect to the computationally optimal rotational speed (STEP-4). Such a difference ΔN can be calculated based on a calculation formula that includes the difference ΔV in the ship speed and numerical values specific to the propeller 13 as parameters. As an example, in the present embodiment, as the calculation formula, [Number] [Number] [Number] (However, α3, α2, and α1 are values specific to the propeller) Calculate the difference ΔN in rotational speed using the various formulas (1) to (3) above-mentioned. In the present embodiment, when the ship speed changes to V±ΔV due to the influence of the wind during the navigation of the ship 10, the propeller rotational speed is changed from the current rotational speed N to a new rotational speed N±ΔN, thereby performing control so as to maintain the ship speed V at the set ship speed V0.

[0045] Subsequently, determine whether the difference ΔV between the set ship speed V0 and the average ship speed V X exceeds a predetermined threshold value. The predetermined threshold value refers to a threshold value set upward (denoted as "threshold value of set ship speed (+)" in FIG. 5) and a threshold value set downward (denoted as "threshold value of set ship speed (−)" in FIG. 5) centered on the set ship speed V0, and can be set to any value.

[0046] When the difference ΔV between the set ship speed V0 and the average ship speed V X does not exceed the predetermined threshold value (refer to the state on the left side among the two "STEP4" shown in FIG. 5), the process of increasing or decreasing the rotational speed N of the propeller 13 is not performed. On the other hand, when the difference between the set ship speed V0 and the average ship speed V XIf the difference ΔV exceeds a predetermined threshold (if the difference ΔV is not within the predetermined range) (see the state on the right of the two "STEP4" shown in Figure 5), the propeller 13 rotation speed N is increased or decreased (STEP-5). The increase or decrease is performed, for example, by having the computer 42 execute a predetermined procedure for the increase or decrease based on a program for increase or decrease processing stored in the storage device 41 of the control device 40 (hereinafter, for convenience, this may be referred to as the "Load Down / Up program"). As an example, if the difference ΔV exceeds the upper limit of the threshold (the threshold of the set ship speed (+)), the above increase or decrease processing is performed to reduce the rotation speed N of the propeller 13 and decelerate the ship speed V (see Figure 5).

[0047] As described above, when performing the increase / decrease process, the rotational speed N of the propeller 13 may be increased or decreased in steps. For example, in this embodiment, when decelerating (reducing the rotational speed), the rotational speed is reduced in steps of 1 rotation every minute, and when accelerating (increasing the rotational speed), the rotational speed is increased in steps of 1 rotation every 4 minutes (STEP-6). The graph in Figure 5 shows an example of decelerating by gradually reducing the rotational speed N of the propeller 13 (see Figure 5).

[0048] After the increase / decrease process is performed, the control device 40 determines whether the predetermined conditions are met. If the conditions are met, the Load Down / Up program is turned off, the increase / decrease process is terminated, and the rotational speed N of the propeller 13 is maintained (STEP-7). Various conditions can be set as predetermined conditions. As an example, in this embodiment, the following three conditions (hereinafter referred to as CASE-1, CASE-2, and CASE-3, respectively) are set. CASE-1 is that the ship speed V reaches the set ship speed V0, and CASE-2 is that the ship speed V is less than or equal to the set ship speed V0 (in the example shown in Figure 5, the ship speed V becomes less than or equal to the set ship speed V0) (see Figures 4 and 5). In CASE-2 and CASE-3, if the ship speed V has not reached the set ship speed V0, the propeller 13 rotation speed N is changed to N±ΔN, and the ship speed V after static stabilization (unlike automobiles, ships change speed gradually, so there is a time lag before the set ship speed is reached after changing to a predetermined rotation speed. It takes time for the rotation speed and ship speed to stabilize after the change, and the state in which these are stable is called static stabilization) is equal to or equal to the set ship speed V0 (in the example shown in Figure 5, the ship speed V is equal to or equal to the set ship speed V0) (see Figures 4 and 5). As an example, in this embodiment, if the ship speed V has not reached the set ship speed V0, the propeller 13 rotation speed N is changed to N-ΔN, and if the ship speed V after static stabilization is equal to or equal to the set ship speed V0, it corresponds to CASE-2, and if the ship speed V after static stabilization is equal to or greater than the set ship speed V0, it corresponds to CASE-3, and the Load Down / Up program is turned off (see Figures 4 and 5).

[0049] After the increase / decrease processing is completed as described above and the rotational speed N of the propeller 13 is maintained (STEP-7), the system is set to not accept command signals to change the rotational speed N for a predetermined time (for example, T minutes) (STEP-8). At this time, the main engine controller 30 transmits a message to the control device 40 indicating that it is not possible to change the rotational speed of the main engine 11 (see Figure 3). Providing a predetermined interval time T between the processing to change the rotational speed N of the propeller 13 to N±ΔN and the processing to change it to N±ΔN again helps to prevent hunting (unstable idling; vibrations that occur during idling; a phenomenon in which the speed and position do not stabilize around the indicated target value and fluctuate up and down).

[0050] After the increase / decrease process is completed and a predetermined interval time T has elapsed, the process returns to STEP-4 (STEP-9) as one cycle of the constant ship speed control process, and the average ship speed V of the ship 10 within the predetermined measurement time ΔT is measured. X Calculate the set ship speed V0 and the average ship speed V X The process of determining whether the difference ΔV is within a predetermined range is performed again (STEP-4), and the process moves to the next cycle. After this, each process from STEP-4 to STEP-9 is repeated (see Figure 4).

[0051] According to the ship speed control system 100 described above, even when the auxiliary propulsion force fluctuates greatly due to rapid fluctuations in natural energy, the ship speed V can be automatically controlled to a constant level. This makes it possible to achieve efficient navigation without waste, for example, by considering the thrust of the main engine 11, which consists of the engine (internal combustion engine) 12, to be equivalent to that obtained by the auxiliary propulsion device 14 in tailwind conditions, thereby reducing fuel consumption and thrust. Furthermore, it goes without saying that automatically controlling the ship speed V to a constant level can contribute to smooth navigation by arriving at the destination on schedule, and consequently, to preventing disruptions to logistics and other operations.

[0052] While the embodiments described above are examples of preferred implementations of the present invention, they are not limited thereto, and various modifications are possible without departing from the spirit of the invention. [Industrial applicability]

[0053] The present invention is suitable for application to a ship speed control system for controlling the cruising speed of a ship and to a ship equipped with the system. [Explanation of symbols]

[0054] 10…Ship 11…Main engine (main propulsion device) 12…Engine (internal combustion engine) 13…Propeller 14…Auxiliary propulsion device 15…Sailing device (first auxiliary propulsion device) 15A…Support shaft 15S…Sail 16…Rotating sail (a second auxiliary propulsion device that obtains thrust through the Magnus effect) 17...Control device for auxiliary propulsion system 18...Kite 20... Ship speed detection device 21...Water Vessel Speed ​​Measuring Instrument 22... Ground-based ship speed measuring instrument 30…Main unit controller 31…User Interface 40…Control device 41...Storage device 42… Computer 100... Ship speed control system N... Propeller rotation speed (immediately before control begins) ΔN…The difference between the calculated optimal rotational speed derived from the difference in ship speed ΔV. t...time T... Control interval time (variable) ΔT…Measurement time for average ship speed V0...Set ship speed V…Ship speed VR... Ship speed setting range V X ...average ship speed at a predetermined measurement time ΔT ΔV…Set ship speed V0 and average ship speed V X The difference

Claims

1. A system for controlling the cruising speed of a ship, The main propulsion system of the vessel, including an internal combustion engine and a propeller driven by the internal combustion engine, An auxiliary propulsion device that uses natural energy to assist the propulsion force of the aforementioned vessel, A ship speed detection device that detects the ship's cruising speed, A main engine controller that controls the main propulsion system, The ship's cruising speed is set to a predetermined speed V. 0 A control device that determines whether the propeller rotation speed N is within a predetermined range, and if it is not within the predetermined range, transmits a signal to the main engine controller to change the propeller rotation speed N based on the result of a calculation based on a predetermined propeller rotation speed during constant ship speed control. Equipped with, During control by the control device, the ship speed detection device constantly detects the ship's cruising speed. The cruising speed of the vessel is either its speed over water or its speed over land. The average ship speed VX of the vessel within a predetermined measurement time ΔT is calculated, and it is determined whether the difference ΔV between the set ship speed V0 and the average ship speed VX is within the predetermined range. If the difference ΔV is not within the predetermined range, the propeller rotation speed N is increased or decreased. The rotational speed N of the propeller is increased or decreased in stages. If, after the process of increasing or decreasing the propeller rotation speed N, the ship's speed V has not reached the set ship speed V 0, the propeller rotation speed N is changed to N ± ΔN. A ship speed control system that calculates the aforementioned ΔN based on a formula that includes the difference ΔV of the ship speed and a value specific to the propeller as parameters.

2. The ship speed control system according to Claim 1, wherein, after the process of increasing or decreasing the rotational speed N of the propeller, if the ship speed V of the ship has reached the set ship speed V 0, the rotational speed N of the propeller is maintained.

3. The above calculation formula is: [Math 1] [Math 2] [Math 3] (However, α 3 , α 2 , α 1 (This is a value specific to the propeller.) A ship speed control system according to claim 1, using the following:

4. The ship speed control system according to claim 3, wherein a predetermined interval time T is provided after the process of changing the propeller rotation speed N to N±ΔN, and before the process of changing to the next N±ΔN.

5. After the predetermined interval time T has elapsed, the average ship speed V of the vessel within the predetermined measurement time ΔT X The set ship speed V is calculated and 0 and the average ship speed V X The ship speed control system according to claim 4, further comprising the process of determining whether the difference ΔV is within the predetermined range.

6. The ship speed control system according to claim 5, wherein the auxiliary propulsion device is a sailing device that receives wind using a sail or kite installed on the hull of the ship.

7. The ship speed control system according to claim 6, wherein the sail or kite of the sailing device is deformable or detachable so as to change the force it receives from the wind.

8. The ship speed control system according to claim 7, wherein the sail is made of steel or FRP.

9. The ship speed control system according to claim 8, further comprising a second auxiliary propulsion device that obtains propulsion force by the Magnus effect, in addition to the first auxiliary propulsion device comprising the sailing device.

10. A ship equipped with the ship speed control system according to any one of claims 1 to 9.

11. The vessel according to claim 10, which is a bulk carrier.

Images