Ship propulsion system

Abstract

The present invention relates to a ship propulsion system and, more particularly, to a ship propulsion system in which, when a propulsion shaft is operating abnormally or is predicted to operate abnormally while a shaft generator is applying a rotational force to the propulsion shaft, a control unit variably controls the application of the rotational force by the shaft generator, thereby preventing damage to the propulsion shaft in an abnormal operation situation, and a PTI mode can be stably controlled.

Description

ship propulsion system

[0001] The present invention relates to a ship propulsion system.

[0002] A ship's propulsion system typically generates propulsion by rotating a propulsion shaft via the main engine, which in turn drives a propulsion motor. Furthermore, a dual-mode system is widely adopted, with the propulsion shaft coupled to a shaft generator. This allows for both a Power Take-Off (PTO) mode, which extracts the rotational power of the main engine to generate electricity, and a Power Take-In (PTI) mode, which supplies external power and adds rotational power to the propulsion shaft to assist propulsion.

[0003] PTI mode is typically used for high-speed operation of ships, reducing the load on the main engine, and improving fuel consumption efficiency. Recently, its importance has been highlighted as a key component of a hybrid propulsion system in conjunction with eco-friendly fuels or battery-based power sources.

[0004] However, the PTI mode operation method according to the conventional technology has limitations in that it does not sufficiently secure an algorithm or automated response logic to flexibly control operating conditions according to operating conditions or shaft status.

[0005] In particular, when a vessel encounters rough seas or extreme sea conditions, such as propeller racing, where the propeller is exposed above the waterline due to rising waves, or crash astern, where the rotation direction of the propeller shaft abruptly reverses during a sudden stop to avoid a collision or obstacle in the ocean. In these abnormal operating conditions, the rotational speed or torque of the propeller shaft changes rapidly, and if the PTI mode continuously applies rotational force at this time, it may result in overload and mechanical damage to the shafting system, such as the propeller shaft, coupling, and gears.

[0006] The purpose of the present invention is to provide a ship propulsion system capable of stably operating a shaft generator in PTI mode. The objectives of the present invention are not limited to those mentioned above, and other unmentioned objectives will be readily apparent to those skilled in the art from the description below.

[0007] A ship propulsion system according to one aspect of the present invention includes a propulsion shaft that rotates by a main engine and drives a propulsion unit; a shaft generator that generates power using the rotational force of the propulsion shaft or receives power from an external source and applies rotational force to the propulsion shaft; and a control unit that variably controls the application of rotational force to the shaft generator when abnormal operation of the propulsion shaft is detected or predicted, wherein the abnormal operation of the propulsion shaft indicates a state in which the rotational speed of the propulsion shaft increases to a critical speed or higher.

[0008] The above control unit can reduce the amount of rotational power applied to the shaft generator or stop the application of rotational power when abnormal operation of the propulsion shaft is detected or predicted.

[0009] The control unit receives rotational speed and torque information of the propulsion shaft, and when the received rotational speed of the propulsion shaft is greater than or equal to the critical speed and the torque of the propulsion shaft is less than the critical torque, it can determine that the propulsion machine is operating abnormally.

[0010] The control unit controls the rotational power applied to the shaft generator to be less than or equal to a smaller value among an output command value and an output upper limit value when abnormal operation of the propulsion shaft is detected or predicted, and the output command value is set based on at least one of the rotational speed, torque, and a value set by an operator of the propulsion shaft, and the output upper limit value can be set based on a torque limit value of the propulsion shaft or the power that can be supplied from an external power source that supplies power to the shaft generator.

[0011] The control unit receives weather forecast information and ship operation information, and based on the received weather forecast information and ship operation information, if the predicted wave height of the sea area where the ship will be located in the future is higher than a predetermined standard, it can predict that an abnormal operation state in which the propulsion shaft rotates at a critical speed or higher will occur.

[0012] The control unit predicts the occurrence of the abnormal driving state by inputting the received weather prediction information and the ship's operation information into a pre-learned driving prediction model, and the driving prediction model may be a supervised learning deep learning model using the weather prediction information configured for each time interval and the ship's operation information at the corresponding point in time as input values, and the rotational speed of the propulsion shaft as an output value.

[0013] The present invention has the effect of enabling stable operation of a shaft generator even under abnormal operating conditions. The effects of the present invention are not limited to those mentioned above, and other effects not mentioned will be clearly understood by those of ordinary skill in the art from the description of the claims.

[0014] Figure 1 is a schematic diagram of a ship propulsion system according to an embodiment of the present invention.

[0015] Figure 2 is a flowchart showing the rotational power application control of the shaft generator according to the first embodiment of the present invention.

[0016] Figure 3 is a flowchart showing the rotational power application control of the shaft generator according to the second embodiment of the present invention.

[0017] Figure 4 is a flowchart showing the rotational power application control of the shaft generator according to the third embodiment of the present invention.

[0018] Fig. 5 is a flowchart showing the rotational power application control of the shaft generator according to the fourth embodiment of the present invention.

[0019] Fig. 6 is a flowchart showing the rotational power application control of the shaft generator according to the fifth embodiment of the present invention.

[0020] Fig. 7 is a flowchart showing the rotational power application control of the shaft generator according to the sixth embodiment of the present invention.

[0021] Fig. 8 is a flowchart showing the rotational power application control of the shaft generator according to the seventh embodiment of the present invention.

[0022] Fig. 9 is a flowchart showing the rotational power application control of the shaft generator according to the eighth embodiment of the present invention.

[0023] FIG. 10 is a flowchart showing the rotational power application control of the shaft generator according to the ninth embodiment of the present invention.

[0024] The objects, specific advantages, and novel features of the present invention will become more apparent from the following detailed description and preferred embodiments, taken in conjunction with the accompanying drawings. In this specification, when reference numerals are assigned to components in each drawing, it should be noted that, where possible, identical components are given the same reference numerals even if they appear in different drawings. Furthermore, in describing the present invention, if a detailed description of a related known technology is deemed to unnecessarily obscure the gist of the present invention, the detailed description thereof will be omitted.

[0025] In addition, the attached drawings are only intended to facilitate easy understanding of the embodiments disclosed in this specification, and the technical ideas disclosed in this specification are not limited by the attached drawings, and should be understood to include all modifications, equivalents, or substitutes included in the spirit and technical scope of the present invention.

[0026] Additionally, terms including ordinal numbers, such as first, second, etc., may be used to describe various components, but the components are not limited by the terms. The terms are used only to distinguish one component from another.

[0027] The present invention encompasses a vessel equipped with the ship propulsion system described below. The term "vessel" encompasses gas carriers, merchant ships transporting various cargoes or people, and offshore plants such as FLNG and FSRU.

[0028] Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the attached drawings.

[0029] FIG. 1 is a conceptual diagram of a ship propulsion system according to an embodiment of the present invention. For reference, FIG. 1 is a conceptual diagram illustrating at least a portion of the components included in one embodiment.

[0030] Referring to FIG. 1, a ship propulsion system (1) according to an embodiment of the present invention includes a main engine (10), a propulsion shaft (30), a propulsion device (40), a shaft generator (20), a first converter (50), a second converter (60), a transformer (70), a generator engine (80), and a control unit (not shown).

[0031] The main engine (10) is connected to a propulsion device (40) installed at the stern through a propulsion shaft (30), and the rotational force generated from the main engine (10) is transmitted to the propulsion device (40) through the propulsion shaft (30) to propel the ship. At this time, the propulsion device (40) may be a propeller, and the propeller can rotate through the rotational force from the main engine (10) to form a fluid flow and move the ship forward.

[0032] The main engine (10) is an internal combustion engine that generates power by burning oil fuel (HFO, MDO, etc.) and / or gas fuel (LNG, LPG, etc.), and in the present embodiment, may be a two-stroke propulsion engine such as a ME-GI engine (MAN Electronic-Gas Injection Engine).

[0033] The output of the main engine (10) may vary due to at least one of changes in the system load of the ship, changes due to sea conditions, and changes occurring in the main engine itself, and such changes in the output of the main engine (10) may be reflected in the torque applied to the propulsion shaft (30).

[0034] The shaft generator (20) generates electric power by extracting at least a portion of the power generated by the main engine (10). The shaft generator is a type of power take-off device (Power Take-Off PTO) in that it extracts and uses a portion of the power supplied to the propulsion unit from the main engine (10). This method of generating power using the shaft generator is effective in saving energy through economical power generation during ship operation.

[0035] Meanwhile, the shaft generator (20) can operate as a motor that rotates the propulsion shaft when power is supplied from the outside, thereby assisting the propulsion power of the main engine (10), and in this case, it functions as a power take-in (PTI).

[0036] That is, the shaft generator (20) functions as a generator that produces electricity by utilizing the surplus power of the main engine (10) in PTO mode, and can operate as a boost motor that applies rotational power to the propulsion shaft (30) together with the main engine (10) in PTI mode.

[0037] When the shaft generator (20) operates in PTI mode, the rotational force applied by the shaft generator (20) directly affects the rotational speed of the propulsion shaft (30). Accordingly, when the amount of rotational force applied by the shaft generator (20) increases, the rotational speed of the propulsion shaft (30) increases, and when the amount of rotational force applied decreases, the rotational speed of the propulsion shaft (30) decreases.

[0038] The shaft generator (20) may be an engine mounted type (Engine Mounted Shaft Generator, EMG) installed at the free end of the main engine (10) or an in-line type (In-line type shaft generator) installed on the propulsion shaft between the main engine (10) and the propulsion unit.

[0039] The first converter (50) converts the variable frequency AC power generated by the shaft generator (20) into DC power and supplies it to the DC link. This eliminates voltage and frequency fluctuations due to changes in rotational speed, thereby enabling stable power conversion.

[0040] Meanwhile, the first converter (50) can operate as an inverter that converts DC power into AC power and supplies it when power is supplied from the DC link to the shaft generator (20) (e.g., when the shaft generator operates in PTI mode). That is, the first converter (50) is an AC-DC / DC-AC dual-purpose conversion device configured to enable bidirectional power flow, and can flexibly control the power conversion direction depending on the driving mode of the propulsion shaft.

[0041] The second converter (60) reconverts the direct current power transmitted via the DC link into alternating current power with the voltage, frequency, and phase conditions required by the ship's system and supplies it to the switchboard or system load. This enables the supply of power appropriate for the rated alternating current load and enables flexible response to various system demands.

[0042] Meanwhile, the second converter (60) performs a rectifier operation to convert AC power into DC power when power from the AC grid is supplied to the DC link. In other words, the second converter (60) is a DC-AC / AC-DC dual-purpose conversion device configured to enable bidirectional power flow, and can flexibly control the power conversion direction depending on the conditions of the grid load or the operating mode.

[0043] The transformer (70) converts the AC power converted by the second converter (60) into a required voltage level and supplies it to the distribution panel. Accordingly, power loss is minimized and stable power transmission is enabled.

[0044] A generator engine (80) is installed onboard and drives a generator under the control of the control unit to generate AC power. The generator may be a diesel generator, but is not limited thereto. In the present embodiment, the shaft generator (20) may operate in PTI mode by receiving power generated by the generator engine (80), but is not limited thereto.

[0045] When the propulsion shaft (30) is operating abnormally or is predicted to operate abnormally, the control unit variably controls the rotational power applied to the shaft generator (20) to ensure that the propulsion shaft operates stably even in abnormal situations.

[0046] In this embodiment, the control unit detects the state of the propulsion shaft and the external environment, and receives current operating state information such as the rotation speed, torque, and vibration of the propulsion shaft and external environment information of the ship such as the sea state (e.g., wave height, current), and the position of surrounding ships, in order to control the amount of rotational power applied accordingly. In addition, the control unit detects or predicts abnormal operation of the propulsion shaft based on the received information, and variably controls the amount of rotational power applied to the shaft generator (20) based on the judgment result.

[0047] Meanwhile, in this embodiment, the 'control unit' is a configuration that comprehensively performs functions between the upper controller (PMS) that commands PTI operation and the device controller that performs actual power application. These functions may be implemented as a single integrated module or may be implemented in a distributed manner as separate linked devices.

[0048] The control unit according to the present embodiment can independently set the output of the main engine (10) and the PTI output by the shaft generator (20) according to the position of the lever of the ship when the shaft generator (20) operates in the PTI mode. Typically, when the shaft generator (20) applies rotational force to the propulsion shaft (30) and the rotational speed of the propulsion shaft (30) increases, the main engine (10) performs load sharing in which the output is automatically reduced to maintain the target rotational speed. However, the control unit according to the present embodiment controls so that the application of rotational force in the PTI mode does not cause a reduction in the output of the main engine (10), thereby enabling operation in a boost mode in which the PTI output is additionally added while the output of the main engine (10) is maintained.

[0049] More specifically, the control unit according to the present embodiment receives a signal indicating whether the PTI mode is activated from the Bridge Maneuvering System (BMS) installed on the bridge according to the operation of the ship operator. The operator can select the PTI mode through the operation button (PB) provided in the BMS, in which case the BMS transmits the corresponding status information to the control unit. When the control unit receives the PTI mode operation signal, the control unit controls the total output applied to the propulsion shaft (30) to be increased by variably applying the PTI output of the shaft generator (20) in addition to the output of the main engine (10) corresponding to the lever position while maintaining the output. As a result, the total output of the propulsion shaft (30) is improved without reducing the output of the main engine (10) in the PTI mode, and accordingly, the rotation speed (RPM) of the propulsion shaft (30) can also be increased.

[0050] For example, when the lever position is 'Slow', in the conventional method where the PTI output by the shaft generator (20) is not applied, the output of the main engine (10) is P slow is fixed, and rotational force is applied to the propulsion shaft (30) only with this output. In contrast, the control unit according to the present embodiment determines that the maximum PTI output of the shaft generator (20) according to the rotational speed of the propulsion shaft (30) is P PTI(rpm) In this case, the lever position is 'Slow' and the propeller shaft (30) is P slow + P PTI(rpm) By controlling the output to be authorized, the effect of increasing actual propulsion power and RPM can be secured.

[0051] Hereinafter, with reference to FIGS. 2 to 10, the rotational force application control operation of the control unit according to the present embodiment will be examined in detail.

[0052]

[0053] Fig. 2 is a flowchart illustrating the rotational power application control of a shaft generator (20) according to the first embodiment of the present invention. Referring to Fig. 2, at step 210, the control unit receives rotational speed information of the propulsion shaft (30). In the ship propulsion system (1) according to the present embodiment, various detection methods can be applied to detect the rotational speed of the propulsion shaft (30) in real time.

[0054] For example, the rotational speed of the propulsion shaft (30) can be detected with high precision through a rotary encoder installed on the propulsion shaft (30). In addition, by attaching a magnetic or iron toothed wheel to the propulsion shaft (30) and placing a magnetic pulse sensor (Magnetic Pickup Unit) at a corresponding position, the rotational speed can be detected through the frequency of the voltage signal induced when the tooth passes in front of the sensor. In addition, when the propulsion shaft is structured to be linked to an electric motor or a shaft generator, the rotational speed can also be indirectly estimated by analyzing the operating conditions such as the output frequency, current, and voltage from the inverter or VFD (variable frequency drive) control information of the corresponding electric motor. This method has the advantage of being able to calculate the rotational speed without additionally installing a separate sensor, but the precision may be somewhat lower than that of the direct measurement method.

[0055] Meanwhile, in the ship propulsion system (1) according to the present embodiment, the rotation speed of the propulsion shaft (30) can be detected by a shaft meter including a rotation sensor installed on the propulsion shaft (30) and a torque sensor installed at a position capable of detecting torsional deformation of the propulsion shaft (30).

[0056] In step 220, the control unit determines whether the propulsion shaft (30) is operating abnormally based on the rotation speed of the propulsion shaft (30) received in step 210. In the present embodiment, if the rotation speed of the propulsion shaft (30) is less than a preset threshold speed, the control unit determines that the propulsion shaft (30) is operating normally and proceeds to step 230.

[0057] Meanwhile, if the rotation speed of the propulsion shaft (30) is higher than a preset threshold speed, the control unit determines that the propulsion shaft (30) is operating abnormally and enters step 240.

[0058] In this embodiment, the abnormal operating state in which the propeller shaft (30) rotates at a speed exceeding the critical speed may include a propeller racing state in which the propeller (40) is exposed above the water surface during navigation, the load on the propeller shaft (30) is rapidly reduced, and the propeller (40) rotates excessively quickly.

[0059] In consideration of this, in another embodiment of the present invention, the control unit may determine that the propulsion shaft (30) is in an abnormal operation state when the rotational speed of the propulsion shaft (30) is higher than the critical speed and the torque of the propulsion shaft (30) is lower than a predetermined critical torque. In this way, by considering not only the rotational speed of the propulsion shaft (30) but also the torque of the propulsion shaft (30), the abnormal operation state in which the propulsion unit (40) is exposed above the sea surface can be more reliably detected. At this time, the torque of the propulsion shaft (30) may be directly measured by a shaft meter, or may be calculated from the output of the propulsion shaft (30) and the rotational speed of the propulsion shaft (30).

[0060] At step 230, if it is determined that the propulsion shaft (30) is in a normal operating state, the control unit controls the shaft generator (20) to apply a rotational force corresponding to the rotational speed of the propulsion shaft (30) to the propulsion shaft (30) according to a basic power curve representing the rotational speed of the propulsion shaft (30) and the output corresponding to the rotational speed.

[0061] In another embodiment, the control unit may comprehensively consider the output status of the main engine (10), the power available from an external power source, the required propulsion power of the ship, etc., to calculate the rotational force to be applied to the propulsion shaft through the shaft generator (20), and control the shaft generator (20) to apply the calculated amount of rotational force to the propulsion shaft (30).

[0062] Specifically, when the main engine (10) is operating under an excessive load or under an operating condition in which fuel consumption efficiency is reduced, the control unit can control to auxiliary apply a certain level of rotational power to the propulsion shaft (30) through the shaft generator (20) in order to reduce the output burden of the main engine (10) and improve fuel efficiency. At this time, the upper limit of the rotational power that can be applied is restricted according to the power that can be supplied from an external power source such as a battery or a fuel cell, and the control unit calculates an appropriate amount of application by taking into account the corresponding supply capacity.

[0063] That is, the control unit calculates in real time the magnitude of the rotational force to be applied by the shaft generator (20) based on the driving efficiency of the main engine (10), the load status of the propulsion shaft (30), the amount of power that can be supplied from an external power source, etc., and controls the operation of the shaft generator (20) based on this, thereby enabling the optimal rotational force to be applied to the propulsion shaft (30).

[0064] At step 240, if it is determined that the propulsion shaft (30) is in an abnormal operating state, the control unit reduces the rotational force applied through the shaft generator (20) or stops the application of the rotational force, thereby preventing excessive mechanical load from being transmitted to the shaft system and securing the mechanical stability of the propulsion shaft (30).

[0065] More specifically, in the present embodiment, when the propulsion shaft (30) is rotating at a speed higher than the critical speed, if the shaft generator (20) operates in the PTI mode and supplies additional rotational power to the propulsion shaft (30), the propulsion shaft (30) rotates faster, which increases the load on the shaft system. Therefore, in the present embodiment, when the control unit determines that the propulsion shaft (30) is in an abnormal operating state in which it is rotating at a critical speed or higher, the control unit reduces the amount of rotational power applied to the propulsion shaft (30) by the shaft generator (20) operating in the PTI mode or stops applying the rotational power, thereby reducing the load on the shaft system.

[0066] In this embodiment, the control unit outputs the maximum value of the rotational force applied by the shaft generator (20) as the output command value (P ref ) and output upper limit (P limit ) can be determined as a smaller value, and can be reduced below the determined value.

[0067] Output command value (P ref ) is a target value of the rotational force to be applied to the propulsion shaft (30) through the shaft generator (20), and can be variably set based on at least one of the rotational speed of the propulsion shaft (30), torque, and a value set by the operator.

[0068] Output upper limit (P limit ) is the upper limit of the rotational power that the shaft generator (20) can apply, and is set by reflecting the torque limit of the propulsion shaft (30) or the power that can be supplied from an external power source. For example, if there is a concern that the torque of the propulsion shaft (30) may exceed the critical value, the torque value (N m) is converted into a power value (kW) and the output upper limit value (P limit) can be set to limit the PTI output from being excessively applied, and the output upper limit (P) can be set according to the available power of the generator engine (80) that supplies power to the shaft generator (20). limit ) can be automatically adjusted. For this purpose, the control unit can obtain information on the available power of the generator engine (80) in real time. Output upper limit value (P limit ) can be automatically adjusted by real-time calculations or learning algorithms based on past driving history.

[0069] The control unit outputs the command value (P ref ) and output upper limit (P limit ) is determined as the maximum power output of the shaft generator (20), thereby preventing excessive rotational power from being applied to the propulsion shaft (30) and preventing overload or wear of the propulsion shaft (30). This power application amount control of the shaft generator (20) can be performed in real time, and accordingly, the PTI output can be instantly lowered even in an abnormal operating state, enabling stable PTI control.

[0070] In addition, the control unit according to the present embodiment can control the rotational power distribution of the main engine (10) and the shaft generator (20) when the main engine (10) and the shaft generator (20) simultaneously apply rotational power to the propulsion shaft (30), i.e., when the PTI mode of the shaft generator (20) is in operation.

[0071] More specifically, when the control unit determines that the speed of the ship exceeds the target speed while the rotational power is applied by the shaft generator (20), the control unit can control the ship to sail at the target speed by reducing the output of the main engine (10).

[0072] Meanwhile, if the control unit determines that the speed of the ship is lower than the target speed even though rotational power is being applied by the shaft generator (20), it can control the ship to sail at the target speed by increasing the output of the main engine (10).

[0073] This control is intended to stably maintain the target rotational speed of the propulsion shaft (30) by sharing the rotational power between the main engine (10) and the shaft generator (20). The control unit prevents excessive rotational power from being applied to the propulsion shaft (30) by appropriately adjusting the output of the main engine (10) in a situation where the shaft generator operates in PTI mode, thereby improving the overall propulsion efficiency.

[0074] According to this embodiment, when the rotation speed of the propulsion shaft (30) or the main engine (10) increases rapidly, the control unit can immediately reduce the amount of rotational power applied by the shaft generator (20) or stop the application of rotational power, thereby preventing damage to the shaft system due to overspeed rotation.

[0075]

[0076] Figure 3 is a flowchart illustrating the rotational power application control of a shaft generator (20) according to a second embodiment of the present invention. Referring to Figure 3, at step 310, the control unit receives maritime forecast information. In this embodiment, the maritime forecast information is information for predicting abnormal operation of the propulsion shaft (30), and may include weather forecast information and navigation information.

[0077] Weather forecast information can be weather forecast data generated at predetermined time intervals for grid points dividing the world's oceans into specified longitude and latitude units. For example, the control unit can obtain weather forecast data from servers providing environmental information, such as the Korea Meteorological Administration (KMA), weather-related company servers, the Ministry of Land, Infrastructure and Transport (MOLIT), map-related company servers, and geography-related company servers. Weather forecast information can include weather information related to vessel operation, such as wave direction, wave height, wind direction, and wind speed.

[0078] Meanwhile, a radar-type wave gauge is installed on the ship, and the control unit can obtain information about waves around the ship from this.

[0079] Operational information may include information related to the vessel's navigational status, such as the vessel's current location, direction of travel, speed, and distance traveled. In this embodiment, operational information may be calculated for each section, such as the vessel's direction of travel and speed for each section.

[0080] At step 320, the control unit predicts the possibility that the propulsion shaft (30) of the ship will operate abnormally based on the sea prediction information received at step 310. In one embodiment of the present invention, the control unit determines that propeller racing may occur in the sea area where the ship will be located in the future, based on the current location of the ship, wave height, and sailing direction information, if the predicted wave height is higher than a predetermined standard, and thus predicts that an abnormal operation state in which the propulsion shaft (30) rotates at a critical speed or higher will occur.

[0081] In another embodiment of the present invention, the control unit can apply the received maritime prediction information to a pre-trained driving prediction model to predict abnormal vessel operation. The driving prediction model may be a deep learning model that uses the maritime prediction information to predict vessel abnormal operation.

[0082] For example, the driving prediction model may be a deep learning model that is supervised learning, using as input values ​​weather prediction information organized for each time interval (e.g., wave height, wave direction, wind speed for each hour) and the ship position, sailing direction, and speed at that point in time, and using as output values ​​the rotation speed of the actual propulsion shaft (30). For example, the control unit may learn the driving prediction model in a supervised learning manner based on previously collected maritime prediction information and the rotation speed information of the actual propulsion shaft (30) corresponding thereto.

[0083] The control unit can predict the future rotation speed of the propulsion shaft (30) by inputting the real-time received maritime prediction information into the driving prediction model learned in this way, and if the predicted rotation speed of the propulsion shaft (30) is higher than the critical speed, it can be determined that the propulsion shaft (30) will operate abnormally.

[0084] If the control unit does not predict that the propulsion shaft (30) will operate abnormally, it enters step 330, and if the propulsion shaft (30) is predicted to operate abnormally, it enters step 340.

[0085] At step 330, if the propulsion shaft (30) is predicted to operate normally, the control unit controls the shaft generator (20) to apply a rotational force corresponding to the rotational speed of the propulsion shaft (30) to the propulsion shaft (30) according to the basic power curve representing the rotational speed of the propulsion shaft (30) and the output corresponding to the rotational speed.

[0086] In another embodiment, the control unit may comprehensively consider the output status of the main engine (10), the power available from an external power source, the required propulsion power of the ship, etc., to calculate the rotational force to be applied to the propulsion shaft through the shaft generator (20), and control the shaft generator (20) to apply the calculated amount of rotational force to the propulsion shaft (30).

[0087] At step 340, if it is predicted that the propulsion shaft (30) will operate abnormally, the control unit reduces the rotational force applied through the shaft generator (20) or stops the application of the rotational force, thereby preventing excessive mechanical load from being transmitted to the propulsion shaft (30) in advance and ensuring the mechanical stability of the propulsion shaft (30).

[0088] More specifically, if the propulsion shaft (30) is predicted to rotate at a speed higher than the critical speed, the shaft generator (20) operates in the PTI mode and supplies additional rotational power to the propulsion shaft (30), which may increase the burden on the shaft system in the future. Therefore, in the present embodiment, if the control unit is predicted to rotate the propulsion shaft (30) at a speed higher than the critical speed, the shaft generator (20) operates in the PTI mode and reduces the amount of rotational power applied to the propulsion shaft (30), or stops applying the rotational power, thereby reducing the burden on the shaft system in advance.

[0089] In this embodiment, the control unit outputs the maximum value of the rotational force applied by the shaft generator (20) as the output command value (P ref ) and output upper limit (P limit ) can be determined as a smaller value, and can be reduced below the determined value.

[0090] Output command value (P ref ) is a target value of the rotational force to be applied to the propulsion shaft (30) through the shaft generator (20), and can be variably set based on at least one of the rotational speed of the propulsion shaft (30), torque, and a value set by the operator.

[0091] Output upper limit (P limit ) is the upper limit of the rotational power that the shaft generator (20) can apply, and is set by reflecting the torque limit of the propulsion shaft (30) or the power that can be supplied from an external power source. For example, if there is a concern that the torque of the propulsion shaft (30) may exceed the critical value, the torque value (N m) is converted into a power value (kW) and the output upper limit value (P limit) can be set to limit the PTI output from being excessively applied, and the output upper limit (P) can be set according to the available power of the generator engine (80) that supplies power to the shaft generator (20). limit ) can be automatically adjusted.

[0092] The control unit outputs the command value (P ref ) and output upper limit (P limit ) is determined as the maximum power output of the shaft generator (20), thereby preventing excessive rotational power from being applied to the propulsion shaft (30) and preventing overload or wear of the propulsion shaft (30). This power application amount control of the shaft generator (20) can be performed in real time, and accordingly, the PTI output can be instantly lowered even in an abnormal operating state, enabling stable PTI control.

[0093] According to this embodiment, when abnormal operation of the propulsion shaft (30) is predicted, the control unit can prevent damage to the shaft system due to overspeed rotation by reducing the amount of rotational power applied by the shaft generator (20) in advance or stopping the application of rotational power.

[0094]

[0095] Fig. 4 is a flowchart illustrating the rotational power application control of a shaft generator (20) according to a third embodiment of the present invention. Referring to Fig. 4, at step 410, the control unit receives rotational speed information of the propulsion shaft (30). In the ship propulsion system (1) according to the present embodiment, various detection methods can be applied to detect the rotational speed of the propulsion shaft (30) in real time.

[0096] In step 420, the control unit determines whether the propulsion shaft (30) is operating abnormally based on the rotation speed of the propulsion shaft (30) received in step 410. In the present embodiment, if the rotation speed of the propulsion shaft (30) is less than a preset threshold speed, the control unit determines that the propulsion shaft (30) is operating normally and proceeds to step 430, and if the rotation speed of the propulsion shaft (30) is greater than or equal to the threshold speed, the control unit determines that the propulsion shaft (30) is operating abnormally and proceeds to step 460.

[0097] At step 430, the control unit receives maritime forecast information. In this embodiment, the maritime forecast information is information for predicting abnormal operation of the propulsion shaft (30), and may include weather forecast information and operational information.

[0098] At step 440, the control unit predicts the possibility that the propulsion shaft (30) of the ship will operate abnormally based on the sea prediction information received at step 430. In one embodiment of the present invention, the control unit determines that propeller racing may occur in the sea area where the ship will be located in the future, based on the current location of the ship, wave height, and sailing direction information, if the predicted wave height is higher than a predetermined standard, and thus predicts that an abnormal operation state in which the propulsion shaft (30) rotates at a critical speed or higher will occur.

[0099] In another embodiment of the present invention, the control unit can apply the received maritime prediction information to a pre-trained driving prediction model to predict abnormal vessel operation. The driving prediction model may be a deep learning model that uses the maritime prediction information to predict vessel abnormal operation.

[0100] The control unit can predict the future rotation speed of the propulsion shaft (30) by inputting the real-time received maritime prediction information into the driving prediction model learned in this way, and if the predicted rotation speed of the propulsion shaft (30) is higher than the critical speed, it can be determined that the propulsion shaft (30) will operate abnormally.

[0101] If the control unit does not predict that the propulsion shaft (30) will operate abnormally based on the results of the driving prediction model, it enters step 450, and if the propulsion shaft (30) is predicted to operate abnormally, it enters step 460.

[0102] At step 450, if the propulsion shaft (30) is predicted to operate normally, the control unit controls the shaft generator (20) to apply a rotational force corresponding to the rotational speed of the propulsion shaft (30) to the propulsion shaft (30) according to the basic power curve representing the rotational speed of the propulsion shaft (30) and the output corresponding to the rotational speed.

[0103] In another embodiment, the control unit may comprehensively consider the output status of the main engine (10), the power available from an external power source, the required propulsion power of the ship, etc., to calculate the rotational force to be applied to the propulsion shaft through the shaft generator (20), and control the shaft generator (20) to apply the calculated amount of rotational force to the propulsion shaft (30).

[0104] At step 460, if the propulsion shaft (30) is predicted to operate abnormally, the control unit reduces the rotational force applied through the shaft generator (20) or stops the application of the rotational force, thereby preventing excessive mechanical load from being transmitted to the propulsion shaft (30) and ensuring the mechanical stability of the propulsion shaft (30).

[0105] More specifically, when the propulsion shaft (30) rotates at a speed higher than the critical speed or is predicted to rotate, the shaft generator (20) operates in the PTI mode and supplies additional rotational power to the propulsion shaft (30), which may increase the burden on the shaft system. Therefore, in the present embodiment, when the propulsion shaft (30) rotates at a speed higher than the critical speed or is predicted to rotate, the control unit reduces the amount of rotational power applied to the propulsion shaft (30) by the shaft generator (20) operating in the PTI mode or stops applying the rotational power, thereby reducing the burden on the shaft system.

[0106] In this embodiment, the control unit outputs the maximum value of the rotational force applied by the shaft generator (20) as the output command value (P ref ) and output upper limit (P limit ) can be determined as a smaller value, and can be reduced below the determined value.

[0107] Output command value (P ref ) is a target value of the rotational force to be applied to the propulsion shaft (30) through the shaft generator (20), and can be variably set based on at least one of the rotational speed of the propulsion shaft (30), torque, and a value set by the operator.

[0108] Output upper limit (P limit ) is the upper limit of the rotational power that the shaft generator (20) can apply, and is set by reflecting the torque limit of the propulsion shaft (30) or the power that can be supplied from an external power source. For example, if there is a concern that the torque of the propulsion shaft (30) may exceed the critical value, the torque value (N m) is converted into a power value (kW) and the output upper limit value (P limit ) can be set to limit the PTI output from being excessively applied, and the output upper limit (P) can be set according to the available power of the generator engine (80) that supplies power to the shaft generator (20). limit ) can be automatically adjusted. For this purpose, the control unit can obtain information on the available power of the generator engine (80) in real time.

[0109] The control unit outputs the command value (P ref ) and output upper limit (P limit ) is determined as the maximum power output of the shaft generator (20), thereby preventing excessive rotational power from being applied to the propulsion shaft (30) and preventing overload or wear of the propulsion shaft (30). This power application amount control of the shaft generator (20) can be performed in real time, and accordingly, the PTI output can be instantly lowered even in an abnormal operating state, enabling stable PTI control.

[0110] According to this embodiment, first, it is determined whether the current propulsion shaft (30) is in a normal operating state, and if it is determined to be in a normal operating state, it is predicted whether there is a possibility of abnormal operation in the future, and by controlling the amount of rotational power applied to the shaft generator (20), it is possible to not only quickly respond to the current abnormal operation of the propulsion shaft (30), but also to prepare in advance for future abnormal operation, thereby supporting stable operation of the ship.

[0111]

[0112] Fig. 5 is a flowchart illustrating the rotational power application control of a shaft generator (20) according to the fourth embodiment of the present invention. Referring to Fig. 5, at step 510, the control unit receives torque information applied to the propulsion shaft (30).

[0113] In the ship propulsion system (1) according to the present embodiment, various detection methods can be applied to detect the torque of the propulsion shaft (30) in real time. For example, in the ship propulsion system (1) according to the present embodiment, the torque of the propulsion shaft (30) can be detected by a shaft meter including a rotation sensor installed on the propulsion shaft (30) and a torque sensor installed at a position capable of detecting torsional deformation of the propulsion shaft (30).

[0114] In step 520, the control unit determines whether the propulsion shaft (30) is operating abnormally based on the torque of the propulsion shaft (30) received in step 510. In the present embodiment, if the torque of the propulsion shaft (30) is within a preset critical torque range, the control unit determines that the propulsion shaft (30) is operating normally and proceeds to step 530.

[0115] Meanwhile, if the torque of the propulsion shaft (30) is outside the preset critical torque range, the control unit determines that the propulsion shaft (30) is operating abnormally and enters step 540.

[0116] In this embodiment, the abnormal operating state in which the torque of the propulsion shaft (30) is outside the critical torque range may include a crash astern state in which the torque of the propulsion shaft (30) rapidly increases due to the propeller racing and sudden stop of the ship, in which the propulsion shaft (40) is exposed above the water surface during sailing, the load on the propulsion shaft (30) rapidly decreases, and the torque of the propulsion shaft (30) rapidly decreases due to the sudden decrease in the torque of the propulsion shaft (30).

[0117] In consideration of this, in another embodiment of the present invention, the control unit may additionally receive the rotation speed of the propulsion shaft (30) when the torque of the propulsion shaft (30) is outside the critical torque range, and determine abnormal operation of the propulsion shaft (30) based on the torque of the propulsion shaft (30) and the rotation speed of the propulsion shaft (30).

[0118] The control unit may determine that the ship is in a crash astern state in which it makes a sudden stop when the torque of the propulsion shaft (30) exceeds the critical torque range and the rotational speed of the propulsion shaft (30) is less than the critical speed, and may determine that the propulsion shaft (30) is operating abnormally.

[0119] In another embodiment, the control unit may determine that the propulsion shaft (30) is operating abnormally if the torque of the propulsion shaft (30) exceeds a critical torque range and the amount of decrease in the rotational speed of the propulsion shaft (30) within a predetermined period of time is greater than a predetermined threshold value. This is advantageous because, when the ship suddenly stops, the rotational speed of the propulsion shaft (30) rapidly decreases for a short period of time, so such an abnormal condition can be quickly detected.

[0120] Meanwhile, the control unit may determine to perform abnormal operation such as propeller racing when the torque of the propeller shaft (30) is below the critical torque range and the rotational speed of the propeller shaft (30) is above the critical speed.

[0121] At step 530, if it is determined that the propulsion shaft (30) is in a normal operating state, the control unit controls the shaft generator (20) to apply a rotational force corresponding to the rotational speed of the propulsion shaft (30) to the propulsion shaft (30) according to a basic power curve representing the rotational speed of the propulsion shaft (30) and the output corresponding to the rotational speed.

[0122] In another embodiment, the control unit may comprehensively consider the output status of the main engine (10), the power available from an external power source, the required propulsion power of the ship, etc., to calculate the rotational force to be applied to the propulsion shaft through the shaft generator (20), and control the shaft generator (20) to apply the calculated amount of rotational force to the propulsion shaft (30).

[0123] At step 540, if it is determined that the propulsion shaft (30) is in an abnormal operating state, the control unit reduces the rotational force applied through the shaft generator (20) or stops the application of the rotational force, thereby preventing excessive mechanical load from being transmitted to the shaft system and securing the mechanical stability of the propulsion shaft (30).

[0124] More specifically, in the present embodiment, when a torque exceeding the critical torque range is applied to the propulsion shaft (30), the shaft generator (20) operates in the PTI mode and supplies additional rotational power to the propulsion shaft (30), the propulsion shaft (30) rotates faster, which increases the burden on the shaft system. In addition, when a torque less than the critical torque range is applied to the propulsion shaft (30), this may be propeller racing, and in this case, when the shaft generator (20) operates in the PTI mode and supplies additional rotational power to the propulsion shaft (30), the burden on the shaft system may also increase.

[0125] Accordingly, in this embodiment, when the control unit determines that the propulsion shaft (30) is in an abnormal operating state in which it is rotating at a speed outside the critical speed range, the control unit reduces the load on the shaft system by reducing the rotational force applied to the propulsion shaft (30) by the shaft generator (20) operating in the PTI mode or by stopping the application of the rotational force.

[0126] In this embodiment, the control unit outputs the maximum value of the rotational force applied by the shaft generator (20) as the output command value (P ref ) and output upper limit (P limit ) can be determined as a smaller value, and can be reduced below the determined value.

[0127] Output command value (P ref ) is a target value of the rotational force to be applied to the propulsion shaft (30) through the shaft generator (20), and can be variably set based on at least one of the rotational speed of the propulsion shaft (30), torque, and a value set by the operator.

[0128] Output upper limit (P limit ) is the upper limit of the rotational power that the shaft generator (20) can apply, and is set by reflecting the torque limit of the propulsion shaft (30) or the power that can be supplied from an external power source. For example, if there is a concern that the torque of the propulsion shaft (30) may exceed the critical value, the torque value (N m) is converted into a power value (kW) and the output upper limit value (P limit) can be set to limit the PTI output from being excessively applied, and the output upper limit (P) can be set according to the available power of the generator engine (80) that supplies power to the shaft generator (20). limit ) can be automatically adjusted. For this purpose, the control unit can obtain information on the available power of the generator engine (80) in real time.

[0129] The control unit outputs the command value (P ref ) and output upper limit (P limit ) is determined as the maximum power output of the shaft generator (20), thereby preventing excessive rotational power from being applied to the propulsion shaft (30) and preventing overload or wear of the propulsion shaft (30). This power application amount control of the shaft generator (20) can be performed in real time, and accordingly, the PTI output can be instantly lowered even in an abnormal operating state, enabling stable PTI control.

[0130]

[0131] Fig. 6 is a flowchart illustrating the rotational power application control of a shaft generator (20) according to a fifth embodiment of the present invention. Referring to Fig. 6, at step 610, the control unit receives operation prediction information. In this embodiment, the operation prediction information is information for predicting abnormal operation of the propulsion shaft (30), and may include sea level prediction information and obstacle prediction information.

[0132] Marine forecast information may include weather forecast information and navigation information. Weather forecast information may be weather forecast data generated at predetermined time intervals for grid points divided into predetermined longitude and latitude units across the world's oceans. For example, the control unit may obtain weather forecast data from servers providing environmental information, such as the Korea Meteorological Administration (KMA), weather-related company servers, the Ministry of Land, Infrastructure and Transport (MOLIT), map-related company servers, and geography-related company servers. Weather forecast information may include weather information related to vessel operation, such as wave direction, wave height, wind direction, and wind speed.

[0133] Meanwhile, a radar-type wave gauge is installed on the ship, and the control unit can obtain information about waves around the ship from this.

[0134] Operational information may include information related to the vessel's navigational status, such as the vessel's current location, direction of travel, speed, and distance traveled. In this embodiment, operational information may be calculated for each section, such as the vessel's direction of travel and speed for each section.

[0135] Obstacle prediction information is information about obstacles existing within a preset range, and can be collected by radar, HF communication equipment, satellite communication equipment, object detection sensors, etc. and transmitted to the control unit. In the present embodiment, the obstacle prediction information may include ship identification information of other ships located at sea, and may also include information about unidentified obstacles detected by various sensor equipment including radar (RADAR), cameras, and spatial recognition sensors (LIDAR, etc.). Such obstacle prediction information may include information for determining the possibility of collision between a ship and an obstacle, such as the location of the obstacle, the rate of change in the location of the obstacle, the direction and speed of movement of the obstacle.

[0136] At step 620, the control unit predicts the possibility that the ship's propulsion shaft (30) will operate abnormally based on the operation prediction information received at step 610.

[0137] In this embodiment, the control unit determines that propeller racing may occur in the sea area where the ship will be located in the future based on the current location of the ship, wave height, and sailing direction information, and if the predicted wave height is higher than a predetermined standard, the control unit can predict that this will cause an abnormal operating state in which the torque of the propulsion shaft (30) is rapidly reduced and the propulsion shaft (30) rotates at a critical speed or higher.

[0138] In addition, the control unit can predict that an abnormal driving state will occur in which the torque of the propulsion shaft (30) rapidly increases due to the collision between the vessel and the obstacle or due to a sudden stop to avoid the obstacle, when a collision between the vessel and the obstacle is predicted based on the vessel's operating direction information and movement speed and the movement path and speed of the obstacle.

[0139] In this embodiment, the control unit can calculate the angular velocity of the obstacle using the obstacle's movement path and speed, and predict the obstacle's future movement path using the obstacle's speed and angular velocity. Furthermore, the control unit can calculate the vessel's angular velocity using the vessel's movement path and speed, and predict the vessel's future movement path using the vessel's speed and angular velocity. Based on the predicted obstacle and the vessel's future movement path, the control unit can calculate the risk of collision between the obstacle and the vessel.

[0140] In another embodiment of the present invention, the control unit can apply the received driving prediction information to a pre-trained driving prediction model to predict abnormal driving of the vessel. In this case, the driving prediction model may be a deep learning model that uses the driving prediction information to predict whether the vessel is operating abnormally. For example, the driving prediction model may be trained using a supervised learning method using learning data that has as input values ​​weather prediction information (e.g., wave height, wave direction, wind speed, etc.), the vessel's position, speed, navigation direction, obstacle position, moving speed, and angular velocity, etc. organized by time interval, and output values ​​of the propulsion shaft rotation speed and torque values ​​at corresponding points in time.

[0141] The control unit can use these input and output data to train a driving prediction model using supervised learning. The trained model can then receive real-time driving prediction information and predict future propulsion shaft rotation speed and torque. By determining whether the predicted propulsion shaft torque falls within the critical torque range, the control unit can predict whether the vessel is operating abnormally.

[0142] If the control unit does not predict that the propulsion shaft (30) will operate abnormally, it enters step 630, and if the propulsion shaft (30) is predicted to operate abnormally, it enters step 640.

[0143] At step 630, if the propulsion shaft (30) is predicted to operate normally, the control unit controls the shaft generator (20) to apply a rotational force corresponding to the rotational speed of the propulsion shaft (30) to the propulsion shaft (30) according to the basic power curve representing the rotational speed of the propulsion shaft (30) and the output corresponding to the rotational speed.

[0144] In another embodiment, the control unit may comprehensively consider the output status of the main engine (10), the power available from an external power source, the required propulsion power of the ship, etc., to calculate the rotational force to be applied to the propulsion shaft through the shaft generator (20), and control the shaft generator (20) to apply the calculated amount of rotational force to the propulsion shaft (30).

[0145] At step 640, if it is predicted that the propulsion shaft (30) will operate abnormally, the control unit reduces the rotational force applied through the shaft generator (20) or stops the application of the rotational force, thereby preventing excessive mechanical load from being applied to the propulsion shaft (30) in advance and ensuring the mechanical stability of the propulsion shaft (30).

[0146] In this embodiment, the control unit outputs the maximum value of the rotational force applied by the shaft generator (20) as the output command value (P ref ) and output upper limit (P limit ) can be determined as a smaller value, and can be reduced below the determined value.

[0147] Output command value (P ref ) is a target value of the rotational force to be applied to the propulsion shaft (30) through the shaft generator (20), and can be variably set based on at least one of the rotational speed of the propulsion shaft (30), torque, and a value set by the operator.

[0148] Output upper limit (P limit ) is the upper limit of the rotational power that the shaft generator (20) can apply, and is set by reflecting the torque limit of the propulsion shaft (30) or the power that can be supplied from an external power source. For example, if there is a concern that the torque of the propulsion shaft (30) may exceed the critical value, the torque value (N m) is converted into a power value (kW) and the output upper limit value (P limit ) can be set to limit the PTI output from being excessively applied, and the output upper limit (P) can be set according to the available power of the generator engine (80) that supplies power to the shaft generator (20). limit) can be automatically adjusted. For this purpose, the control unit can obtain information on the available power of the generator engine (80) in real time.

[0149] The control unit outputs the command value (P ref ) and output upper limit (P limit ) is determined as the maximum power output of the shaft generator (20), thereby preventing excessive rotational power from being applied to the propulsion shaft (30) and preventing overload or wear of the propulsion shaft (30). This power application amount control of the shaft generator (20) can be performed in real time, and accordingly, the PTI output can be instantly lowered even in an abnormal operating state, enabling stable PTI control.

[0150]

[0151] Fig. 7 is a flowchart illustrating the rotational power application control of a shaft generator (20) according to the sixth embodiment of the present invention. Referring to Fig. 7, at step 710, the control unit receives torque information applied to the propulsion shaft (30).

[0152] In step 720, the control unit determines whether the propulsion shaft (30) is operating abnormally based on the torque of the propulsion shaft (30) received in step 710. In the present embodiment, if the torque of the propulsion shaft (30) is within a preset critical torque range, the control unit determines that the propulsion shaft (30) is operating normally and proceeds to step 730.

[0153] Meanwhile, if the torque of the propulsion shaft (30) is outside the preset critical torque range, the control unit determines that the propulsion shaft (30) is operating abnormally and enters step 760.

[0154] At step 730, the control unit receives driving prediction information. In this embodiment, the driving prediction information is information for predicting abnormal driving of the propulsion shaft (30), and may include sea prediction information and obstacle prediction information.

[0155] At step 740, the control unit predicts the possibility that the ship's propulsion shaft (30) will operate abnormally based on the operation prediction information received at step 730.

[0156] In this embodiment, the control unit determines that propeller racing may occur in the sea area where the ship will be located in the future based on the current location of the ship, wave height, and sailing direction information, and if the predicted wave height is higher than a predetermined standard, the control unit can predict that this will cause an abnormal operating state in which the torque of the propulsion shaft (30) is rapidly reduced and the propulsion shaft (30) rotates at a critical speed or higher.

[0157] In addition, the control unit can predict that an abnormal driving state will occur in which the torque of the propulsion shaft (30) rapidly increases due to the collision between the vessel and the obstacle or due to a sudden stop to avoid the obstacle, when a collision between the vessel and the obstacle is predicted based on the vessel's operating direction information and movement speed and the movement path and speed of the obstacle.

[0158] If the control unit does not predict that the propulsion shaft (30) will operate abnormally, it enters step 750, and if the propulsion shaft (30) is predicted to operate abnormally, it enters step 760.

[0159] At step 750, if the propulsion shaft (30) is predicted to operate normally, the control unit controls the shaft generator (20) to apply a rotational force corresponding to the rotational speed of the propulsion shaft (30) to the propulsion shaft (30) according to the basic power curve representing the rotational speed of the propulsion shaft (30) and the output corresponding to the rotational speed.

[0160] In another embodiment, the control unit may comprehensively consider the output status of the main engine (10), the power available from an external power source, the required propulsion power of the ship, etc., to calculate the rotational force to be applied to the propulsion shaft through the shaft generator (20), and control the shaft generator (20) to apply the calculated amount of rotational force to the propulsion shaft (30).

[0161] At step 760, if it is predicted that the propulsion shaft (30) will operate abnormally, the control unit reduces the rotational force applied through the shaft generator (20) or stops the application of the rotational force, thereby preventing excessive mechanical load from being transmitted to the propulsion shaft (30) in advance and ensuring the mechanical stability of the propulsion shaft (30).

[0162] In this embodiment, the control unit outputs the maximum value of the rotational force applied by the shaft generator (20) as the output command value (P ref ) and output upper limit (P limit ) can be determined as a smaller value, and can be reduced below the determined value.

[0163] Output command value (P ref ) is a target value of the rotational force to be applied to the propulsion shaft (30) through the shaft generator (20), and can be variably set based on at least one of the rotational speed of the propulsion shaft (30), torque, and a value set by the operator.

[0164] Output upper limit (P limit ) is the upper limit of the rotational power that the shaft generator (20) can apply, and is set by reflecting the torque limit of the propulsion shaft (30) or the power that can be supplied from an external power source. For example, if there is a concern that the torque of the propulsion shaft (30) may exceed the critical value, the torque value (N m) is converted into a power value (kW) and the output upper limit value (P limit ) can be set to limit the PTI output from being excessively applied, and the output upper limit (P) can be set according to the available power of the generator engine (80) that supplies power to the shaft generator (20). limit) can be automatically adjusted. For this purpose, the control unit can obtain information on the available power of the generator engine (80) in real time.

[0165] The control unit outputs the command value (P ref ) and output upper limit (P limit ) is determined as the maximum power output of the shaft generator (20), thereby preventing excessive rotational power from being applied to the propulsion shaft (30) and preventing overload or wear of the propulsion shaft (30). This power application amount control of the shaft generator (20) can be performed in real time, and accordingly, the PTI output can be instantly lowered even in an abnormal operating state, enabling stable PTI control.

[0166]

[0167] Fig. 8 is a flowchart illustrating the rotational power application control of a shaft generator (20) according to the seventh embodiment of the present invention. Referring to Fig. 8, at step 810, the control unit receives rotational speed information of the propulsion shaft (30). In the ship propulsion system (1) according to the present embodiment, various detection methods can be applied to detect the rotational speed of the propulsion shaft (30) in real time.

[0168] In step 820, the control unit determines whether the propulsion shaft (30) is operating abnormally based on the rotation speed of the propulsion shaft (30) received in step 810. In this embodiment, if the rotation speed decrease of the propulsion shaft (30) within a predetermined time is greater than or equal to a threshold value, the control unit determines that the propulsion shaft (30) is operating abnormally and proceeds to step 840. Otherwise, the control unit determines that the propulsion shaft (30) is operating normally and proceeds to step 830.

[0169] In this embodiment, the abnormal operating state in which the rotational speed of the propulsion shaft (30) decreases by more than a threshold value within a predetermined period of time may include a crash astern state in which the rotational speed of the propulsion shaft (30) decreases rapidly and the torque of the propulsion shaft (30) increases rapidly due to a sudden stop of the ship.

[0170] Taking this into consideration, in another embodiment of the present invention, the control unit may determine that the propulsion shaft (30) is in an abnormal operation state when the rotational speed of the propulsion shaft (30) decreases by a threshold value or more within a predetermined period of time and the torque of the propulsion shaft (30) is greater than a predetermined threshold torque. In this way, by considering not only the rotational speed of the propulsion shaft (30) but also the torque of the propulsion shaft (30), the abnormal operation state in which the propulsion unit (40) suddenly stops can be more reliably detected.

[0171] At step 830, if it is determined that the propulsion shaft (30) is in a normal operating state, the control unit controls the shaft generator (20) to apply a rotational force corresponding to the rotational speed of the propulsion shaft (30) to the propulsion shaft (30) according to a basic power curve representing the rotational speed of the propulsion shaft (30) and the output corresponding to the rotational speed.

[0172] In another embodiment, the control unit may comprehensively consider the output status of the main engine (10), the power available from an external power source, the required propulsion power of the ship, etc., to calculate the rotational force to be applied to the propulsion shaft through the shaft generator (20), and control the shaft generator (20) to apply the calculated amount of rotational force to the propulsion shaft (30).

[0173] At step 840, if it is determined that the propulsion shaft (30) is in an abnormal operating state, the control unit reduces the rotational force applied through the shaft generator (20) or stops the application of the rotational force, thereby preventing excessive mechanical load from being transmitted to the shaft system and securing the mechanical stability of the propulsion shaft (30).

[0174] In this embodiment, the control unit outputs the maximum value of the rotational force applied by the shaft generator (20) as the output command value (P ref ) and output upper limit (P limit ) can be determined as a smaller value, and can be reduced below the determined value.

[0175] Output command value (P ref) is a target value of the rotational force to be applied to the propulsion shaft (30) through the shaft generator (20), and can be variably set based on at least one of the rotational speed of the propulsion shaft (30), torque, and a value set by the operator.

[0176] Output upper limit (P limit ) is the upper limit of the rotational power that the shaft generator (20) can apply, and is set by reflecting the torque limit of the propulsion shaft (30) or the power that can be supplied from an external power source. For example, if there is a concern that the torque of the propulsion shaft (30) may exceed the critical value, the torque value (N m) is converted into a power value (kW) and the output upper limit value (P limit ) can be set to limit the PTI output from being excessively applied, and the output upper limit (P) can be set according to the available power of the generator engine (80) that supplies power to the shaft generator (20). limit ) can be automatically adjusted. For this purpose, the control unit can obtain information on the available power of the generator engine (80) in real time.

[0177] The control unit outputs the command value (P ref ) and output upper limit (P limit ) is determined as the maximum power output of the shaft generator (20), thereby preventing excessive rotational power from being applied to the propulsion shaft (30) and preventing overload or wear of the propulsion shaft (30). This power application amount control of the shaft generator (20) can be performed in real time, and accordingly, the PTI output can be instantly lowered even in an abnormal operating state, enabling stable PTI control.

[0178]

[0179] Fig. 9 is a flowchart illustrating the rotational power application control of the shaft generator (20) according to the eighth embodiment of the present invention. Referring to Fig. 9, at step 910, the control unit receives obstacle prediction information.

[0180] In this embodiment, the obstacle prediction information is information about obstacles existing within a preset range, and can be collected by radar, HF communication equipment, satellite communication equipment, object detection sensors, etc. and transmitted to the control unit. In this embodiment, the obstacle prediction information can include ship identification information of other ships located at sea, and can also include information about unidentified obstacles detected by various sensor equipment including radar (RADAR), cameras, and spatial recognition sensors (LIDAR, etc.).

[0181] Such obstacle prediction information may include information for determining the possibility of collision between a vessel and an obstacle, such as the location of the obstacle, the rate of change in the location of the obstacle, and the direction and speed of movement of the obstacle.

[0182] At step 920, the control unit predicts the possibility that the propulsion shaft (30) of the ship will operate abnormally based on the obstacle prediction information received at step 910. In this embodiment, if a collision between the ship and the obstacle is predicted based on the ship's navigation direction information and movement speed and the movement path and speed of the obstacle, the control unit can predict that an abnormal operation state will occur in which the rotational speed of the propulsion shaft (30) is reduced by a threshold value or more within a predetermined period of time.

[0183] In this embodiment, the control unit can calculate the angular velocity of the obstacle using the obstacle's movement path and speed, and predict the obstacle's future movement path using the obstacle's speed and angular velocity. Furthermore, the control unit can calculate the vessel's angular velocity using the vessel's movement path and speed, and predict the vessel's future movement path using the vessel's speed and angular velocity. Based on the predicted obstacle and the vessel's future movement path, the control unit can calculate the risk of collision between the obstacle and the vessel.

[0184] In another embodiment of the present invention, the control unit can apply the received obstacle prediction information to a pre-trained collision prediction model to predict abnormal vessel operation. The collision prediction model may be a deep learning model that uses the obstacle prediction information to predict whether the vessel is operating abnormally (i.e., whether the vessel will collide with an obstacle).

[0185] For example, a collision prediction model can be trained using a supervised learning method using learning data that outputs the presence or probability of collision between a ship and an obstacle at a future point in time, based on input values ​​such as obstacle prediction information (e.g., obstacle location, speed, direction of movement, angular velocity, etc.) and ship location, speed, direction of movement, and angular velocity.

[0186] The control unit can use learning data composed of these input and output values ​​to train a collision prediction model using a supervised learning method. The trained model can then receive obstacle prediction information received in real time and predict the possibility of collision between the vessel and the obstacle. If the control unit determines that there is a possibility of collision between the vessel and the obstacle, it can predict that the propulsion shaft (30) will operate abnormally.

[0187] If the control unit does not predict that the propulsion shaft (30) will operate abnormally, it enters step 930, and if the propulsion shaft (30) is predicted to operate abnormally, it enters step 940.

[0188] At step 930, if the propulsion shaft (30) is predicted to operate normally, the control unit controls the shaft generator (20) to apply a rotational force corresponding to the rotational speed of the propulsion shaft (30) to the propulsion shaft (30) according to the basic power curve representing the rotational speed of the propulsion shaft (30) and the output corresponding to the rotational speed.

[0189] In another embodiment, the control unit may comprehensively consider the output status of the main engine (10), the power available from an external power source, the required propulsion power of the ship, etc., to calculate the rotational force to be applied to the propulsion shaft through the shaft generator (20), and control the shaft generator (20) to apply the calculated amount of rotational force to the propulsion shaft (30).

[0190] At step 940, if it is predicted that the propulsion shaft (30) will operate abnormally, the control unit reduces the rotational force applied through the shaft generator (20) or stops the application of the rotational force, thereby preventing excessive mechanical load from being transmitted to the propulsion shaft (30) in advance and ensuring the mechanical stability of the propulsion shaft (30).

[0191] In this embodiment, the control unit outputs the maximum value of the rotational force applied by the shaft generator (20) as the output command value (P ref ) and output upper limit (P limit ) can be determined as a smaller value, and can be reduced below the determined value.

[0192] Output command value (P ref ) is a target value of the rotational force to be applied to the propulsion shaft (30) through the shaft generator (20), and can be variably set based on at least one of the rotational speed of the propulsion shaft (30), torque, and a value set by the operator.

[0193] Output upper limit (P limit ) is the upper limit of the rotational power that the shaft generator (20) can apply, and is set by reflecting the torque limit of the propulsion shaft (30) or the power that can be supplied from an external power source. For example, if there is a concern that the torque of the propulsion shaft (30) may exceed the critical value, the torque value (N m) is converted into a power value (kW) and the output upper limit value (P limit ) can be set to limit the PTI output from being excessively applied, and the output upper limit (P) can be set according to the available power of the generator engine (80) that supplies power to the shaft generator (20). limit) can be automatically adjusted. For this purpose, the control unit can obtain information on the available power of the generator engine (80) in real time.

[0194] The control unit outputs the command value (P ref ) and output upper limit (P limit ) is determined as the maximum power output of the shaft generator (20), thereby preventing excessive rotational power from being applied to the propulsion shaft (30) and preventing overload or wear of the propulsion shaft (30). This power application amount control of the shaft generator (20) can be performed in real time, and accordingly, the PTI output can be instantly lowered even in an abnormal operating state, enabling stable PTI control.

[0195]

[0196] Fig. 10 is a flowchart illustrating the rotational power application control of a shaft generator (20) according to the ninth embodiment of the present invention. Referring to Fig. 10, at step 1010, the control unit receives rotational speed information of the propulsion shaft (30).

[0197] In step 1020, the control unit determines whether the propulsion shaft (30) is operating abnormally based on the rotation speed of the propulsion shaft (30) received in step 1010. In this embodiment, if the rotation speed decrease of the propulsion shaft (30) within a predetermined time is greater than or equal to a threshold value, the control unit determines that the propulsion shaft (30) is operating abnormally and proceeds to step 1060. Otherwise, the control unit determines that the propulsion shaft (30) is operating normally and proceeds to step 1030.

[0198] At step 1030, the control unit receives obstacle prediction information. In the present embodiment, the obstacle prediction information may include information for determining the possibility of collision between the vessel and the obstacle, such as the location of the obstacle, the rate of change in the location of the obstacle, the direction of movement of the obstacle, and the speed of the obstacle.

[0199] At step 1040, the control unit predicts the possibility that the propulsion shaft (30) of the ship will operate abnormally based on the obstacle prediction information received at step 1030. In this embodiment, if a collision between the ship and the obstacle is predicted based on the ship's navigation direction information and movement speed and the movement path and speed of the obstacle, the control unit can predict that an abnormal operation state will occur in which the rotational speed of the propulsion shaft (30) is reduced by a threshold value or more within a predetermined period of time.

[0200] If the control unit does not predict that the propulsion shaft (30) will operate abnormally, it enters step 1050, and if the propulsion shaft (30) is predicted to operate abnormally, it enters step 1060.

[0201] At step 1050, if the propulsion shaft (30) is predicted to operate normally, the control unit controls the shaft generator (20) to apply a rotational force corresponding to the rotational speed of the propulsion shaft (30) to the propulsion shaft (30) according to the basic power curve representing the rotational speed of the propulsion shaft (30) and the output corresponding to the rotational speed.

[0202] In another embodiment, the control unit may comprehensively consider the output status of the main engine (10), the power available from an external power source, the required propulsion power of the ship, etc., to calculate the rotational force to be applied to the propulsion shaft through the shaft generator (20), and control the shaft generator (20) to apply the calculated amount of rotational force to the propulsion shaft (30).

[0203] At step 1060, if it is predicted that the propulsion shaft (30) will operate abnormally, the control unit prevents excessive mechanical load from being transmitted to the propulsion shaft (30) in advance by reducing the rotational force applied through the shaft generator (20) or stopping the application of the rotational force, and secures the mechanical stability of the propulsion shaft (30).

[0204] In this embodiment, the control unit outputs the maximum value of the rotational force applied by the shaft generator (20) as the output command value (P ref) and output upper limit (P limit ) can be determined as a smaller value, and can be reduced below the determined value.

[0205] Output command value (P ref ) is a target value of the rotational force to be applied to the propulsion shaft (30) through the shaft generator (20), and can be variably set based on at least one of the rotational speed of the propulsion shaft (30), torque, and a value set by the operator.

[0206] Output upper limit (P limit ) is the upper limit of the rotational power that the shaft generator (20) can apply, and is set by reflecting the torque limit of the propulsion shaft (30) or the power that can be supplied from an external power source. For example, if there is a concern that the torque of the propulsion shaft (30) may exceed the critical value, the torque value (N m) is converted into a power value (kW) and the output upper limit value (P limit ) can be set to limit the PTI output from being excessively applied, and the output upper limit (P) can be set according to the available power of the generator engine (80) that supplies power to the shaft generator (20). limit ) can be automatically adjusted. For this purpose, the control unit can obtain information on the available power of the generator engine (80) in real time.

[0207] The control unit outputs the command value (P ref ) and output upper limit (P limit ) is determined as the maximum power output of the shaft generator (20), thereby preventing excessive rotational power from being applied to the propulsion shaft (30) and preventing overload or wear of the propulsion shaft (30). This power application amount control of the shaft generator (20) can be performed in real time, and accordingly, the PTI output can be instantly lowered even in an abnormal operating state, enabling stable PTI control.

[0208]

[0209] The present invention encompasses all embodiments resulting from a combination of the above embodiments and known techniques, in addition to the embodiments described above.

[0210] Although the present invention has been described in detail through specific examples, this is intended to specifically explain the present invention, and the present invention is not limited thereto, and it will be apparent that modifications and improvements can be made by those skilled in the art within the technical spirit of the present invention.

[0211] All simple modifications or changes of the present invention fall within the scope of the present invention, and the specific scope of protection of the present invention will be made clear by the appended claims.

Claims

1. A propulsion shaft that rotates by the main engine and drives the propulsion unit; A shaft generator that generates power by utilizing the rotational force of the propulsion shaft or receives power from an external source and applies rotational force to the propulsion shaft; In case abnormal operation of the above propulsion shaft is detected or predicted, a control unit is included that variably controls the rotational power application of the shaft generator, The abnormal operation of the propulsion shaft is a ship propulsion system in which the rotational speed of the propulsion shaft increases above a critical speed.

2. In paragraph 1, The above control unit A ship propulsion system that reduces the amount of rotational power applied to the shaft generator or stops the rotational power application when abnormal operation of the propulsion shaft is detected or predicted.

3. In paragraph 1, The above control unit Receive rotation speed and torque information of the above propulsion shaft, A ship propulsion system, wherein when the received rotational speed of the propulsion shaft is greater than or equal to the critical speed and the torque of the propulsion shaft is less than the critical torque, it is determined that the propulsion machine is operating abnormally.

4. In paragraph 1, The above control unit When abnormal operation of the above propulsion shaft is detected or predicted, the rotational power applied to the shaft generator is controlled to be less than the smaller value among the output command value and the output upper limit value, The above output command value is set based on at least one of the rotation speed of the propulsion shaft, torque, and a value set by the operator, A ship propulsion system, wherein the above output upper limit is set based on the torque limit of the propulsion shaft or the power available from an external power source that supplies power to the shaft generator.

5. In paragraph 1, The above control unit Receive weather forecast information and ship operation information, A ship propulsion system that predicts that an abnormal operating state in which the propulsion shaft rotates at a critical speed or higher will occur when the predicted wave height of the sea area where the ship will be located in the future is higher than a predetermined standard based on the received weather forecast information and ship operation information.

6. In paragraph 5, The above control unit By inputting the received weather forecast information and ship operation information into the pre-learned driving prediction model, the occurrence of the abnormal driving state is predicted, The above driving prediction model is a deep learning model that uses the weather prediction information configured for each time interval and the ship's operation information at the corresponding point in time as input values, and the rotational speed of the propulsion shaft as an output value, which is a ship propulsion system.

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