Control method for a wind propulsion device on a ship

Abstract

A method for controlling a wind propulsion device (300, 600) arranged on a vessel is disclosed. The method includes providing pressure information from a first pressure sensor (302, 616) arranged on a surface of the wind propulsion device, estimating a pressure distribution on the surface of the wind propulsion device based on the pressure information from the first pressure sensor, providing angular position information of the wind propulsion device, estimating an apparent wind angle based on the angular position information of the wind propulsion device and the estimated pressure distribution on the surface of the wind propulsion device, using the estimated apparent wind angle to determine an initial approximation for a control parameter, and using the estimated pressure distribution as feedback in a closed-loop control method to optimize the control parameter of the wind propulsion device.

Description

Technical Field

[0001] The present disclosure relates generally to wind propulsion equipment; more particularly, to a method for controlling a wind propulsion equipment arranged on a vessel. Background Art

[0002] In modern times, the maritime industry has made significant progress in harnessing wind energy to propel vessels such as tankers, cargo ships, passenger ships, and small boats. Wind propulsion devices, such as Magnus rotors or airfoil sails, are increasingly being used to supplement traditional propulsion systems, such as underwater propellers. Specifically, these wind propulsion devices are mounted vertically on a vessel and generate lift (or thrust) perpendicular to the wind flow, which serves as the vessel's propulsion force.

[0003] Generally, it is necessary to accurately control such wind propulsion equipment to ensure the optimal efficiency of such wind propulsion equipment. It is worth noting that, based on the wind conditions around the ship, control parameters (such as the rotation speed and direction of rotation of the Magnus rotor or the angle of attack of the airfoil sail) are regularly monitored and adjusted. The adjustment of such control parameters is usually performed based on information from multiple measuring devices (such as meteorological masts, anemometers or special wind sensors) arranged on the ship for measuring wind direction (or wind angle) and wind speed. However, such measuring devices usually measure the wind conditions at the installation point of the measuring devices, without considering the changes in wind profile and pressure distribution caused by various structures on the ship. In addition, the measuring devices are usually not installed near the wind propulsion equipment. Therefore, the wind conditions recorded by the measuring devices may vary significantly compared to the wind conditions observed at the wind propulsion equipment. Alternatively, if the measuring devices are installed near the wind propulsion equipment, due to the operation of the wind propulsion equipment, the wind propulsion equipment may cause errors in the measuring devices in measuring wind conditions. Therefore, the control parameters for the operation of the wind propulsion equipment determined using such measurement techniques usually result in non-optimal operation of the wind propulsion equipment.

[0004] Furthermore, strain-based measurements can be used to measure the lift or force generated by wind propulsion equipment. Specifically, by measuring the structural bending of the wind propulsion equipment, the force acting on the tower due to the wind can be calculated. However, turbulence caused by the ship's hull or changing environmental conditions significantly affects the force transmitted to the wind propulsion equipment, and the bending induced in the wind propulsion equipment structure may vary accordingly. Furthermore, typical strain-based measurement techniques are designed to measure strains greater than those encountered in wind propulsion equipment. Therefore, such strain-based measurements may be less accurate.

[0005] In view of the above discussion, there exists a need to overcome the aforementioned disadvantages associated with optimizing control parameters of wind propulsion devices. Summary of the Invention

[0006] The present disclosure seeks to provide a method for controlling a wind propulsion device. The present disclosure seeks to provide a solution to the existing problem of inaccurate and unreliable measurement techniques that lead to inefficient operation of wind propulsion devices. Therefore, an object of the present disclosure is to provide a solution that at least partially overcomes the problems encountered in the prior art and to provide an efficient method for optimizing control parameters associated with wind propulsion devices.

[0007] In one aspect, an embodiment of the present disclosure provides a method for controlling a wind propulsion device arranged on a vessel, the method comprising:

[0008] - providing pressure information from at least a first pressure sensor arranged on a surface of the wind propulsion device at a first height H1 relative to the deck of the vessel;

[0009] - estimating the pressure distribution on the surface of the wind propulsion device based on pressure information from at least a first pressure sensor, and

[0010] -Use the estimated pressure distribution as feedback in a closed-loop control method to optimize the control parameters of the wind propulsion device.

[0011] In another aspect, an embodiment of the present disclosure provides a method for controlling a system of a wind propulsion device arranged on a vessel, the method comprising:

[0012] - optimizing the control parameters of each wind propulsion device according to the method for controlling wind propulsion devices arranged on a vessel; and

[0013] - Optimize the overall efficiency of wind propulsion devices by measuring individual differences in performance and taking into account the interactions between each wind propulsion device;

[0014] Therein, the wind propulsion devices are arranged at different positions on the vessel relative to the length of the vessel.

[0015] In yet another aspect, an embodiment of the present disclosure provides a vessel comprising at least two wind propulsion devices, each wind propulsion device comprising at least a first pressure sensor, wherein the first pressure sensor is arranged on the surface of the wind propulsion device at a first height H1 relative to the deck of the vessel, and the vessel is also equipped with a device for executing a method for controlling the wind propulsion devices arranged on the vessel.

[0016] In yet another aspect, an embodiment of the present disclosure provides a software product recorded on a non-transitory machine-readable data storage medium, wherein the software product is executable on computing hardware, the software product being used to implement a method for controlling a wind propulsion device arranged on a vessel.

[0017] The embodiments of the present disclosure substantially eliminate or at least partially solve the above-mentioned problems in the prior art, and enable the wind propulsion device to operate efficiently by optimizing control parameters for the operation of the wind propulsion device.

[0018] Other aspects, advantages, features and objects of the present disclosure will become apparent from the accompanying drawings and detailed description of illustrative embodiments, which are interpreted in conjunction with the appended claims.

[0019] It will be appreciated that features of the present disclosure are susceptible to being combined in various different combinations without departing from the scope of the present disclosure as defined by the appended claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] When read in conjunction with the accompanying drawings, the above summary of the invention and the detailed description of the illustrative embodiments below are better understood. For the purpose of illustrating the present disclosure, exemplary configurations of the present disclosure are shown in the accompanying drawings. However, the present disclosure is not limited to the specific methods and means disclosed herein. In addition, it will be appreciated by those skilled in the art that the accompanying drawings are not drawn to scale. In any possible case, similar elements are represented by the same reference numerals.

[0021] Embodiments of the present disclosure will now be described, by way of example only, with reference to the following drawings, in which:

[0022] Figure 1 is a diagram of steps of a method for controlling a wind propulsion device arranged on a vessel according to an embodiment of the present disclosure;

[0023] Figure 2 is a block diagram illustrating a closed-loop control method for optimizing control parameters according to the present disclosure;

[0024] Figure 3 is an illustration of a Magnus rotor as a wind propulsion device according to an embodiment of the present disclosure;

[0025] Figure 4 is a schematic diagram of the wind inflow at the Magnus rotor;

[0026] Figure 5 Schematic diagram of the pressure distribution at different heights of the Magnus rotor due to uneven inflow;

[0027] Figure 6 is an illustration of an airfoil sail as a wind propulsion device according to an embodiment of the present disclosure;

[0028] Figure 7 is a graph showing the relationship between the rotation speed and the net benefit when the wind propulsion device is implemented as a Magnus rotor according to an embodiment of the present disclosure;

[0029] Figure 8 is a diagram of the forces acting on a Magnus rotor;

[0030] Figure 9 is a diagram of steps of a method of controlling a system for wind propulsion equipment according to an embodiment of the present disclosure; and

[0031] Figure 10 is a schematic diagram of a vessel in different examples of optimizing control parameters according to an exemplary embodiment of the present disclosure.

[0032] In the accompanying drawings, underlined reference numerals are used to indicate the item in which the underlined reference numeral appears or is adjacent to the underlined reference numeral. Ununderlined reference numerals relate to the item identified by the line linking the ununderlined reference numeral to the item. When a reference numeral is ununderlined and is accompanied by an associated arrow, the ununderlined reference numeral is used to identify the overall item to which the arrow points. DETAILED DESCRIPTION

[0033] The following detailed description shows embodiments of the present disclosure and ways in which the embodiments of the present disclosure can be implemented. Although some modes of implementing the present disclosure have been disclosed, those skilled in the art will appreciate that other embodiments for implementing or practicing the present disclosure are also included.

[0034] In one aspect, an embodiment of the present disclosure provides a method for controlling a wind propulsion device arranged on a vessel, the method comprising:

[0035] - providing pressure information from at least a first pressure sensor arranged on a surface of the wind propulsion device at a first height H1 relative to the deck of the vessel;

[0036] - estimating the pressure distribution on the surface of the wind propulsion device based on pressure information from at least a first pressure sensor, and

[0037] -Use the estimated pressure distribution as feedback in a closed-loop control method to optimize the control parameters of the wind propulsion device.

[0038] The method for controlling a wind propulsion device as described herein enables improved control and optimization of the operation of the wind propulsion device. The present disclosure provides an improved method using pressure measurement, which enables real-time estimation of the pressure distribution over the total surface of the wind propulsion device, and also enables estimation of wind conditions, such as wind angle and wind speed around the wind propulsion device. Beneficially, this method of pressure measurement eliminates the need for multiple measuring devices for measuring wind conditions. The method described herein uses direct pressure measurement, which is used to determine the pressure distribution and the forces acting on the wind propulsion device. In addition, the method described in the present disclosure is applicable to many types of wind propulsion devices without the need for significant modifications. Notably, the method of the present disclosure significantly improves the efficiency of wind propulsion devices arranged on a ship, thereby increasing the contribution of the wind propulsion equipment to the overall propulsion of the ship.

[0039] The present disclosure provides a method for controlling a wind propulsion device deployed on a vessel. Herein, the term "vessel" refers to a ship or boat used for purposes such as transporting cargo and passengers, or for ocean exploration. Typically, a vessel uses an engine or turbine for propulsion. A vessel is also equipped with a wind propulsion device to assist the engine in propulsing the vessel. Herein, the term "wind propulsion device" refers to a device used to reduce a vessel's fuel consumption by assisting the main propulsion device (such as an engine or turbine) during movement. Such a wind propulsion device can also be used as the vessel's sole propulsion device. Specifically, the wind propulsion device captures the kinetic energy of the wind surrounding the vessel to assist in the vessel's propulsion. Examples of wind propulsion devices include, but are not limited to, Magnus rotors (such as Flettner rotors) and wing sails (such as wingsails). Wing sails can be, for example, wingsails, rigid sails, or suction wingsails (also known as turbine sails). It is noteworthy that the control parameters of the wind propulsion device are adjusted based on one or more external factors (such as atmospheric pressure, wind speed around the vessel, the vessel's speed, wind flow direction, the vessel's direction of movement, etc.) to ensure optimized propulsion output from the wind propulsion device. The present disclosure provides a method of controlling a wind propulsion device to optimize such control parameters.

[0040] The method includes providing pressure information from at least a first pressure sensor, disposed on a surface of a wind propulsion device at a first height H1 relative to a deck of a vessel. Specifically, the first pressure sensor determines the air pressure on the surface of the wind propulsion device. It will be appreciated that when a vessel is in motion, the flow of wind around the vessel exerts a force on the wind propulsion device, which is used to assist the vessel's movement. The pressure information received from the first pressure sensor disposed on the surface of the wind propulsion device refers to information related to the force exerted by the wind on the wind propulsion device. Examples of pressure sensors include, but are not limited to, differential pressure sensors, pressure anemometers, and piezoelectric pressure sensors. Furthermore, the first height H1 at which the first pressure sensor is disposed is selected based on a number of factors, such as the height of the wind propulsion device, the size of the vessel, and atmospheric and weather conditions in the vessel's typical operating environment. Notably, the first pressure sensor provides pressure information across a cross section of the wind propulsion device at height H1. In an example, the wind propulsion device is a Magnus rotor, wherein a single pressure sensor is disposed on the surface of the Magnus rotor. In this example, as the Magnus rotor rotates, a single pressure sensor that rotates with the Magnus rotor measures pressure information associated with different regions of the cross-section in which the pressure sensor is arranged. In another example, the wind propulsion device is a wing sail, wherein preferably, a plurality of pressure sensors (such as two, three, or four) are arranged on the surface of the wing sail. In this example, each of the plurality of pressure sensors provides pressure information associated with a region on the surface of the wing sail, each pressure sensor being arranged over a region on the surface of the wing sail. Thus, the number of pressure sensors used can be 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 20, 25, 30, 35, or even 40.

[0041] The method includes estimating a pressure distribution on the surface of a wind propulsion device based on pressure information from at least a first pressure sensor. It is noteworthy that the pressure exerted on the surface of the wind propulsion device by wind varies depending on the wind's direction and speed. The at least first pressure sensor disposed on the surface of the wind propulsion device provides information regarding this pressure variation across different portions of the surface of the wind propulsion device. Therefore, based on the pressure information provided by the at least first pressure sensor, the pressure distribution on the surface of the wind propulsion device is estimated. Specifically, the pressure distribution on the surface of the wind propulsion device provides an estimate of the pressure difference between the front and rear sides of the wind propulsion device. When the wind propulsion device is a Magnus rotor, this can be achieved using a single pressure sensor as the Magnus rotor rotates. When the wind propulsion device is a wing sail, the wing sail preferably has at least two pressure sensors disposed thereon, the at least two pressure sensors providing pressure information associated with different regions on the surface of the wing sail. Using this pressure information associated with different regions on the surface of the wind propulsion device, the pressure distribution on the surface of the wind propulsion device is estimated.

[0042] Optionally, the method for controlling a wind propulsion device includes providing angular position information of the wind propulsion device. It is noteworthy that the angular position information of the wind propulsion device refers to parameters related to the positioning and operation information of the wind propulsion device, which parameters affect the propulsion force provided by the wind propulsion device. Specifically, the angular position information of the wind propulsion device significantly affects the moving direction and speed of the ship. In an embodiment, when the wind propulsion device is a Magnus rotor, the angular position information may include but is not limited to the size information of the Magnus rotor (such as height, diameter), the rotation speed of the Magnus rotor and the rotation direction of the Magnus rotor. In an embodiment, when the wind propulsion device is a wing sail, the angular position information may include but is not limited to the type of the wing sail, the size information of the wing sail (such as chord length, height, curvature of the leading edge and trailing edge) and the angle of attack of the wing sail.

[0043] The method may also include estimating the apparent wind angle based on the angular position information of the wind propulsion device and the estimated pressure distribution on the surface of the wind propulsion device. Specifically, the apparent wind angle refers to the flow direction of the wind relative to the wind propulsion device. It is worth noting that the apparent wind angle can be measured relative to one of the middle hulls of the ship (such as the middle of the hull along the center fore-aft line of the ship). It should be understood that the estimated pressure information provides information related to the following areas on the surface of the wind propulsion device, which are subjected to a higher degree of pressure compared to other areas on the surface of the wind propulsion device. Therefore, it can be concluded that the areas subjected to a higher degree of pressure are directly affected by the flow of the wind, and therefore the flow direction of the wind can be estimated along the direction of these areas. Therefore, based on the angular positioning information, the positioning of such areas on the wind propulsion device relative to one of the middle hulls is determined, and the apparent wind angle is therefore estimated.

[0044] When a pressure sensor positioned on the surface of a wind propulsion device coincides with a stagnation point, the pressure measured by the pressure sensor reaches a maximum. A stagnation point is the point where all of the wind's kinetic energy is converted into pressure (potential energy). Generally speaking, for a known sail geometry and sail operating conditions, the location of one or more stagnation points is correlated with the angle of attack. Therefore, if the stagnation point can be found, the angle of attack can be derived. That is, the angle of attack is related to the point at which the measured pressure reaches a maximum.

[0045] The method may also include using the estimated apparent wind angle to determine an initial approximation for a control parameter. Notably, the control parameter varies depending on the type of wind propulsion equipment deployed on the vessel. In one example, the control parameter for a Magnus rotor may be the rotational speed and / or the rotational direction of the Magnus rotor. In another example, the control parameter for an airfoil sail may be the angle of attack of the airfoil sail. It should be understood that the estimated apparent wind angle only provides an initial approximation for the control parameter. Such a control parameter is implemented on the wind propulsion equipment and is regularly adjusted to optimize and improve efficiency.

[0046] In the following, exemplary embodiments are discussed in which the wind propulsion device is a Magnus rotor. Where appropriate, the same details and embodiments apply to other types of wind propulsion devices.

[0047] Throughout this disclosure, the term "Magnus rotor" refers to a longitudinal structure (such as a tower) that rotates along its longitudinal axis and generates a force perpendicular to the longitudinal axis and the direction of wind flow. This force is generated due to the Magnus effect and uses the flow of wind around the vessel to provide propulsion to the vessel. Furthermore, a Magnus rotor may include disc end plates for stabilizing the Magnus rotor. Typically, a Magnus rotor is cylindrical (such as a Flettner rotor), however, the cross-section of a Magnus rotor can be circular, square, rectangular, or any other polygonal shape.

[0048] Optionally, angular position information is provided by an angular position measuring device. Here, the angular position information includes at least one of the rotational speed of the Magnus rotor, the rotation angle of the Magnus rotor, and the rotation direction of the Magnus rotor. The angular position information may optionally include dimensional information of the Magnus rotor (such as height or diameter). Furthermore, the angular position measuring device may be a rotary encoder, a tachometer, a gyroscope, or the like. Specifically, a rotary encoder is a position sensor operable to determine the angular position of the Magnus rotor. It should be understood that angular position information is preferably measured at a high frequency and with high precision to obtain accurate results. Therefore, dedicated equipment (such as a rotary encoder) is used to measure the angular position information. Furthermore, the control parameter includes the optimal rotational speed of the Magnus rotor. It is noteworthy that the optimal rotational speed at which the propulsion force provided to the vessel is maximized is determined based on the apparent wind angle.

[0049] Optionally, the method further comprises calculating the wind speed u. To calculate the wind speed u, the air density ρ is first calculated. Equation (1) gives the mathematical formula for the air density,

[0050]

[0051] where R (比) is the specific gas constant of dry air, p is the atmospheric pressure around the ship, and T is the temperature around the ship. Here, based on the average molar mass of dry air of 28.9645 g / mol, the specific gas constant of dry air R (比) The value is usually 287.058 J.kg -1 .K -1 However, R (比) The value of can vary slightly depending on the molecular composition of the air at a particular location.

[0052] Furthermore, atmospheric pressure p is approximated by measuring the pressure at the rear side of the rotating body or using a dedicated sensor. Here, the rear side of the rotating body refers to the side of the rotating body that does not directly receive any inflow of wind onto the rotating body. Therefore, the pressure at the rear side of the rotating body is unaffected by the flow of wind and is therefore substantially similar to atmospheric pressure. Alternatively, a dedicated sensor (such as a barometric pressure sensor) is used to measure atmospheric pressure. Furthermore, a temperature sensor (such as a thermometer or thermistor) is typically used to determine the temperature T.

[0053] The maximum dynamic pressure q on the surface of the Magnus rotor is then calculated by subtracting the atmospheric pressure p from the maximum pressure on the surface of the Magnus rotor. The maximum pressure on the surface of the Magnus rotor is typically determined using pressure information from at least a first pressure sensor arranged on the surface of the Magnus rotor. The calculated air density ρ and the maximum dynamic pressure q are then substituted into equation (2) to calculate the wind speed u,

[0054]

[0055] The method then includes determining an optimal rotation direction of the Magnus rotor using the estimated apparent wind angle. Notably, the rotation direction of the Magnus rotor can be clockwise or counterclockwise. In an example, the apparent wind angle indicates wind flowing from the starboard side of the vessel to the port side of the vessel. In this example, the optimal rotation direction of the Magnus rotor can be counterclockwise to generate a Magnus force toward the bow of the vessel.

[0056] Furthermore, the method includes determining initial approximate values for control parameters using the calculated wind speed and the estimated apparent wind angle. As previously mentioned, the control parameters for the Magnus rotor include the optimal rotational speed of the Magnus rotor. Notably, the rotational speed of the Magnus rotor is adjusted to optimize the ratio of the rotational speed to the wind speed, thereby optimizing the propulsion generated by the Magnus effect. It should be understood that propulsion increases with increasing rotational speed of the Magnus rotor. However, fuel is consumed to generate the rotation in the Magnus rotor, and this fuel consumption increases with increasing rotational speed. Therefore, the rotational speed of the Magnus rotor is optimized in such a way that the benefit obtained from the propulsion generated by the rotation of the Magnus rotor is greater than the fuel consumed by the rotation of the Magnus rotor.

[0057] Optionally, the method further comprises providing pressure information from at least a second pressure sensor, wherein

[0058] - a second pressure sensor is arranged at a second height H2 relative to the deck of the vessel;

[0059] the difference between the first height H1 and the second height H2 is at least 20% of the total height H of the Magnus rotor; and

[0060] - Based on the pressure information from at least the first and second pressure sensors, an estimation of the pressure distribution is performed by interpolating and extrapolating the pressure distribution on the surface of the Magnus rotor.

[0061] Optionally, in this regard, a second pressure sensor is positioned on the vessel to estimate the pressure distribution on the surface of the Magnus rotor with greater accuracy than using only the pressure information from the first pressure sensor. It should be understood that due to uneven wind flow, the pressure distribution varies at different heights on the Magnus rotor. Therefore, the second pressure sensor, positioned at height H2 and at a height difference of at least 20% between the total height H and the height H1 of the first pressure sensor, provides pressure information that differs from the pressure information provided by the first pressure sensor. Thus, information from two different pressure sensors at different heights can be used to perform interpolation and extrapolation of pressure information. Specifically, the first and second pressure sensors, positioned at different heights H1 and H2, respectively, provide insight into how the pressure distribution varies with altitude. This pressure distribution variation can then be extrapolated and interpolated to estimate the pressure distribution on the surface of the Magnus rotor. It should be understood that in embodiments where the first and second pressure sensors are mounted at the terminal ends of the Magnus rotor, only interpolation may be required to estimate the pressure distribution on the surface of the Magnus rotor. In the simplified exemplary illustration, the pressure variation is estimated as a function of height, such as a linear function or a power function. In addition, based on the pressure information provided by multiple pressure sensors, a complex fluid dynamics model can be calculated to estimate the pressure distribution on the surface of the Magnus rotor.

[0062] Optionally, the method further comprises arranging at least a third pressure sensor on the surface of the Magnus rotor, wherein the third pressure sensor is arranged at a third height H3 relative to the deck of the vessel, and the differences between the first height H1, the second height H2 and the third height H3 are each at least 10% of the total height H of the Magnus rotor.

[0063] Optionally, the method further comprises arranging a plurality of another pressure sensors on the surface of the Magnus rotor, wherein each of the another pressure sensors is arranged at a given height relative to the deck of the vessel, and a difference between the heights of each of the pressure sensors is at least 5% of a total height H of the Magnus rotor, and wherein the number of the another pressure sensors is at least four.

[0064] Alternatively, as previously mentioned, due to uneven wind flow, the pressure distribution varies at different heights of the Magnus rotor. Therefore, multiple pressure sensors are installed at different heights to estimate the pressure distribution on the surface of the Magnus rotor with greater accuracy. Furthermore, the height difference between each of the pressure sensors is ensured to enable recording of pressure information at substantially different heights, thereby obtaining a better estimate of the pressure distribution across the entire height of the Magnus rotor. Advantageously, the accuracy of the pressure distribution estimated through interpolation and extrapolation of pressure information increases as the number of pressure sensors providing pressure information increases.

[0065] Optionally, the pressure sensors are arranged along a line generally parallel to the rotational axis of the Magnus rotor. As previously mentioned, a Magnus rotor is a longitudinal structure with its longitudinal axis serving as its rotational axis. Therefore, the pressure sensors are arranged along a straight line on the surface of the Magnus rotor that is generally parallel to the rotational axis.

[0066] Alternatively, the pressure sensors are optionally arranged along a spiral line. Specifically, an imaginary spiral line is outlined on the surface of the Magnus rotor.

[0067] Optionally, the method further comprises measuring the Magnus rotor force by combining strain measurement and displacement measurement of the lower support point. It should be understood that the Magnus force F generated by the Magnus rotor m is counteracted by the forces from the upper bearing and lower support points arranged in the Magnus rotor support structure. While counteracting the Magnus force, the Magnus rotor may experience plastic bending and displacement of the support points. It is worth noting that the upper bearing provides a reaction force F mb To limit the plastic bending of the Magnus rotor. Here, the Magnus rotor undergoes plastic bending, which causes a measurable strain ΔL / L o , where L o The reference length to be measured after plastic bending is the specified length change ΔL. The measuring system needs to be calibrated to understand the correlation between the upper bearing load and strain. This correlation value is called sensitivity. Sensitivity S se Given by equation (3),

[0068]

[0069] Among them F mb is the measured or known upper bearing force, ΔL / L o is the corresponding strain value. Then, when the sensitivity is known, the upper support force is obtained by multiplying the sensitivity by the measured strain value. F mb is linearly related to the strain value. In addition, the displacement of the lower support point is subjected to the force F calculated using equation (4)lb Constraints,

[0070] F lb =k lb x(4);

[0071] where x is the displacement of the lower support point, k lb is the calibrated measured value of the spring constant for the lower support point. K lb is a function of displacement x. It is worth noting that the total Magnus force should be F mb and F lb The method also includes using the measured Magnus rotor forces as feedback for optimizing the operation of the Magnus rotor. It is noteworthy that, advantageously, the strain-based measurement results of the Magnus rotor forces can be used for cross-validation of pressure-based measurement results. In addition, the amplitude of plastic bending and displacement observed in the Magnus rotor is very small. Therefore, a complex measurement arrangement (such as an arrangement comprising the electrical connection of two strain gauge resistance bridges mounted at opposite ends of the Magnus rotor) is adopted to produce an amplified strain signal. Beneficially, the diametrically opposed measurement results from such sensors offset the effects of thermal expansion in the Magnus rotor. In the following, an exemplary embodiment is discussed in which the wind propulsion device is a wing sail. Whenever appropriate, the same details and embodiments apply to other types of wind propulsion devices.

[0072] Throughout this disclosure, the term "foil sail" refers to a structure deployed on a vessel whose cross-section is in the shape of an airfoil, which generates aerodynamic forces when moving through the air. It is noteworthy that a foil sail, when moving through air or wind, penetrates the air and generates aerodynamic forces. Due to the sail's airfoil structure and the movement of wind along the airfoil, the pressure on the convex side of the foil sail is lower than the pressure on the concave side of the foil sail. Alternatively, in the case of a symmetrical foil profile, the pressure difference is generated by the angle of attack. Consequently, this pressure difference generates a force from high-pressure areas to low-pressure areas. This force generated by the pressure difference is at least partially used to propel the vessel. Here, the frontmost edge of the foil sail that directly penetrates the wind flow is called the leading edge, and the rear or trailing edge of the sail, opposite the leading edge, is called the trailing edge. Furthermore, the straight line between the leading and trailing edges is called the chord line of the foil sail. Similarly, the line between the leading and trailing edges, which outlines the surface of the foil sail, is called the chord line of the foil sail. It should be understood that for a given airfoil, different chords and chord lines may exist at different heights. Notably, the chord line is used to determine the angle of attack of the airfoil. Specifically, the angle of attack is used to control the aerodynamic force generated by the airfoil and is defined as the angle between the chord line and a vector representing the direction of wind flow. Examples of airfoils include, but are not limited to, soft sails, rigid sails, and suction sails (also known as turbine sails).

[0073] Optionally, additional pressure information is provided from a second pressure sensor, located on the surface of the airfoil at a height H1 relative to the vessel's deck. Notably, the second pressure sensor is located at the same height H1 as the first pressure sensor to measure pressure information at the same height of the airfoil, but at different regions of the airfoil's cross-section. Specifically, the first and second pressure sensors are located at different chord-wise locations on the airfoil, separated by a distance D1 of at least 20% of the chord length. Here, chord length refers to the length of the chord line connecting the leading and trailing edges. Notably, the first and second pressure sensors are located at substantially different regions of the airfoil to obtain pressure information at different regions of the airfoil's cross-section, thereby estimating the pressure distribution on the surface of the airfoil with greater accuracy. Furthermore, the first and second pressure sensors are located on opposite sides of the airfoil. Here, opposite sides of the airfoil refer to different surfaces connecting the leading and trailing edges of the airfoil. As previously mentioned, different pressures are observed on opposite sides of the airfoil. It should be understood that this pressure difference indicates the propulsive force provided by the airfoil. Therefore, a first pressure sensor and a second pressure sensor are arranged on opposite sides of the airfoil sail to estimate this pressure differential. Alternatively, the first pressure sensor is arranged on one side of the airfoil sail, and the second pressure sensor is arranged on the leading edge of the airfoil sail. As previously mentioned, the leading edge of the airfoil is the frontmost edge of the airfoil that directly penetrates the wind flow. The pressure observed at the leading edge can provide further insights into the impact of the airfoil sail's angle of attack on the resulting propulsion and the vessel's speed. Further alternatively, the first and second pressure sensors are arranged on the same side of the airfoil sail.

[0074] Alternatively, the first pressure sensor and the second pressure sensor are arranged along the chord of the airfoil sail at a distance D1 from each other of at least 20% of the chord length.

[0075] As mentioned above, for a Magnus rotor, similarly for an airfoil sail, the method also includes calculating the wind speed u. First, the air density ρ is calculated. Equation (5) gives the mathematical formula for air density:

[0076]

[0077] where R (比)is the specific gas constant of dry air, p is the atmospheric pressure around the vessel, and T is the temperature around the vessel. It is worth noting that a dedicated sensor is used for the atmospheric pressure p. Alternatively, in a preferred embodiment, a dedicated sensor (such as an air pressure sensor) is used to measure the atmospheric pressure. Subsequently, the maximum dynamic pressure q on the surface of the airfoil is calculated by subtracting the atmospheric pressure p from the maximum pressure on the surface of the airfoil. The maximum pressure on the surface of the airfoil is determined using pressure information from at least a first pressure sensor arranged on the surface of the airfoil. Subsequently, the calculated air density ρ and the maximum dynamic pressure q are substituted into equation (6) to calculate the wind speed u,

[0078]

[0079] Subsequently, the method includes determining an optimal angle of attack for the wing sail using the estimated apparent wind angle. Here, for the wing sail, the angle of attack significantly and primarily affects the aerodynamic force (i.e., lift) generated by the wing sail. Therefore, the angle of attack is optimized based on the estimated apparent wind angle. The method also includes determining initial approximate values for control parameters using the calculated wind speed and the estimated apparent wind angle. Here, the control parameters primarily include the angle of attack of the wing sail. In addition to the wind angle, the wind speed significantly affects the aerodynamic force generated by the wing sail, and therefore, the angle of attack is further optimized based on the wind speed. Therefore, the method includes repeatedly recalculating and reestimating various parameters to maintain optimized control parameters for the wind propulsion device.

[0080] Optionally, the method also includes providing pressure information from at least a third pressure sensor, wherein the third pressure sensor is arranged at a third chord-wise position. Alternatively, the third pressure sensor is arranged along the same chord as the first and second pressure sensors. It is noteworthy that the airfoil sail has multiple chords at different heights along the airfoil sail. For example, the line connecting the leading edge and trailing edge at height H1 is a different chord than the line connecting the leading edge and trailing edge at height H2, etc. In this case, the third pressure sensor is arranged along the same chord as the first and second pressure sensors. Optionally, the first, second, and third pressure sensors are arranged at intervals of at least 10% along the chord of the airfoil sail. It is noteworthy that due to uneven wind flow, the pressure distribution varies at different locations along the chord of the airfoil sail. Therefore, the three pressure sensors are installed at different distances along the chord to estimate the pressure distribution on the surface of the airfoil sail with greater accuracy. Optionally, the third sensor is arranged on the opposite side of the airfoil sail from one or both of the first and second pressure sensors.

[0081] Optionally, the method further includes disposing a plurality of additional pressure sensors on the surface of the wing sail along at least two different chords of the wing sail, wherein the pressure sensors are distributed between the sides of the wing sail and the leading edge of the wing sail. Here, the plurality of additional pressure sensors are disposed at different chords on the surface of the wing sail, on the sides of the wing sail, and on the leading edge of the wing sail to accurately estimate the pressure distribution across the entire surface of the wing sail. Notably, a computational fluid dynamics model can be constructed for the wing sail, wherein such a model can interpolate and extrapolate pressure information from the pressure sensors to simulate an operating model of the wing sail, in which changes in control parameters (such as angle of attack) and their effects on propulsion are estimated in real time. Thus, the pressure information from the plurality of pressure sensors strategically positioned on the surface of the wing sail enables highly accurate interpolation and extrapolation, resulting in a simulation of the wing sail that closely mimics its actual behavior. In an example, a wing sail may have six pressure sensors arranged on the wing sail, wherein a first pressure sensor, a second pressure sensor, and a third pressure sensor are arranged along the same chord, the first pressure sensor and the second pressure sensor are arranged on opposite sides of the wing sail, and the third pressure sensor is arranged on the trailing edge of the wing sail. A fourth pressure sensor of the six pressure sensors is arranged at the trailing edge of the wing sail, and a fifth pressure sensor and a sixth pressure sensor are arranged on opposite sides of the wing sail along different chords. Thus, the number of pressure sensors used may be 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 20, 25, 30, 35, or even 40.

[0082] Optionally, the method further includes

[0083] - measurement of the sail forces by combining plastic bending measurements and displacement measurements of bearings arranged at the connection of the sail to its foundation;

[0084] - Use the measured airfoil sail forces as feedback to optimize airfoil sail operation.

[0085] It should be understood that the aerodynamic force F generated by the airfoil A The airfoil is counteracted by forces from bearings arranged in the support structure. While counteracting the aerodynamic forces, the airfoil may undergo plastic bending and displacement of the support points. The plastic bending of the airfoil causes a strain ΔL / L that can be measured. o , where L o The reference length is the length change ΔL to be measured after undergoing plastic bending. The measuring system needs to be calibrated to understand the correlation between load and strain. This correlation value is called sensitivity. Sensitivity S se Given by equation (7),

[0086]

[0087] Among them F L is the measured or known force, ΔL / L o is the corresponding strain value. Then, when the sensitivity is known, the aerodynamic force is obtained by multiplying the sensitivity by the measured strain value. F L The method also includes using the measured aerodynamic forces as feedback for optimizing sail operation. It is noteworthy that strain-based measurements of aerodynamic forces can be advantageously used to cross-validate pressure-based measurements.

[0088] It will be appreciated that it is also possible to implement wind propulsion devices other than Magnus rotors and wing-shaped sails, in which the method described above is applicable. Furthermore, the various embodiments and variations disclosed above with respect to the aforementioned Magnus rotors are applicable, mutatis mutandis, to wing-shaped sails, and vice versa.

[0089] A method for controlling a wind propulsion device arranged on a vessel includes using an estimated pressure distribution as feedback in a closed-loop control method to optimize control parameters of the wind propulsion device. Notably, after determining an initial approximate value for the control parameter, the control parameter is implemented on the wind propulsion device. It should be understood that due to changes in the control parameter, the pressure distribution on the surface of the wind propulsion device changes significantly. This change in pressure distribution is estimated to analyze the impact of the changed control parameter. After implementing the changed control parameter, this estimated pressure distribution is used as feedback in the method described above to optimize the control parameters of the wind propulsion device. In an example, the initial approximate value of the control parameter causes a change in the pressure distribution that reduces the propulsion force provided by the wind propulsion device. Therefore, this change in pressure distribution is provided as feedback, and another approximate value of the control parameter is determined for the wind propulsion device.

[0090] In the following, a method for controlling a system of wind propulsion devices arranged on a vessel is disclosed. It is worth noting that the vessel comprises at least two wind propulsion devices on the vessel. The wind propulsion devices are arranged at different positions on the vessel relative to the length of the vessel. In the example, for a length L of the vessel v The first wind propulsion device (such as a Magnus rotor) is arranged along the center fore-aft line of the ship and along the middle of the hull at a distance of L from the bow of the ship. v / 4, and the second wind propulsion device (such as a second Magnus rotor) is arranged along the aforementioned hull mid-section at a distance of 3L from the bow of the vessel v At a distance of / 4.

[0091] It should be understood that even though each of the wind propulsion devices operates under optimized control parameters determined using the method described above, the system of wind propulsion devices may not operate at optimal efficiency due to turbulent wakes generated by the operation of a given wind propulsion device interfering with and negating the operation of another wind propulsion device. Hereinafter, an improved method for controlling a plurality of wind propulsion devices is provided in a manner such that the operation of a given wind propulsion device does not negatively impact the operation of another wind propulsion device. This method enables optimal control of each of the wind propulsion devices in a manner that compounded the effects from the system of wind propulsion devices to improve the overall efficiency of the system.

[0092] A method for controlling a system of wind propulsion devices arranged on a vessel includes optimizing control parameters for each wind propulsion device according to the method for controlling wind propulsion devices arranged on a vessel described above. First, the control parameters for each of the wind propulsion devices are optimized individually. As described above, the pressure distribution on the surface of each of the wind propulsion devices is estimated to estimate the apparent wind angle of the wind propulsion device. Thus, an initial approximation for the control parameters is determined, and this initial approximation is optimized using the estimated pressure distribution as feedback in a closed-loop control method.

[0093] The method also includes optimizing the overall efficiency of the wind propulsion devices using closed-loop control by measuring individual performance differences and taking into account the interactions between each wind propulsion device. It is noteworthy that a first wind propulsion device positioned upwind may interfere with and negatively impact the efficiency of a second wind propulsion device compared to a second wind propulsion device. Alternatively, the interaction between wind propulsion devices may be caused by overlapping pressure zones of the wind propulsion devices. In particular, if the low-pressure zone of the first wind propulsion device overlaps the high-pressure zone of the second wind propulsion device, the operation of the second wind propulsion device is negatively impacted. Therefore, control parameters of the first wind propulsion device positioned upwind on the vessel are adjusted to alter how the wind inflow around the first propulsion device interacts with the pressure distribution of the second wind propulsion device. It should be understood that a wind propulsion device disrupts the flow of wind reaching another wind propulsion device. This disturbance or change in the wind flow is referred to as the inflow of a given wind propulsion device. Typically, during operation, a wind propulsion device also generates a turbulent wake that disrupts the laminar flow of wind reaching the other wind propulsion device. Thus, the operation of the first wind propulsion device arranged upwind is modified (typically degraded) in such a way that the inflow of the first wind propulsion device and the turbulent wake of the first wind propulsion device do not affect the operation of the second wind propulsion device. In particular, the rotation speed of the first wind propulsion device arranged upwind can be reduced to reduce the area of the resulting inflow and turbulent wake.

[0094] The performance of each of the wind propulsion devices is measured, and differences between each of the wind propulsion devices are determined to analyze the impact of a given wind propulsion device on another wind propulsion device. Specifically, control parameters of a first wind propulsion device are changed to analyze the impact of the first wind propulsion device on the efficiency of a second wind propulsion device. In addition, the pressure distribution of each of the wind propulsion devices is analyzed, and the pressure distribution of each of the wind propulsion devices is combined with the estimated apparent wind angle and angular position information of each of the wind propulsion devices to determine optimized control parameters for the system of wind propulsion devices, thereby improving the overall efficiency of the system. Notably, the impact of changes in the control parameters of the first wind propulsion device on the second wind propulsion device is used as feedback in a closed-loop control method to further optimize the control parameters of the system of wind propulsion devices.

[0095] In an exemplary embodiment, a system for a wind propulsion device deployed on a vessel includes a first Magnus rotor and a second Magnus rotor, arranged at different locations along the length of the vessel. In a first example, the control parameters (such as rotational speed) of the Magnus rotors are not optimized based on the method for controlling a wind propulsion device described above. In this example, the rotational speeds of the two Magnus rotors are determined to be equal, for example, 180 revolutions per minute. This example shows significant overlap between the pressure zones of the Magnus rotors. In a second example, the control parameters are optimized based on the method for controlling a wind propulsion device described above. Based on this method, the rotational speed of the second Magnus rotor is optimized to 140 revolutions per minute. This optimization significantly reduces fuel consumption. However, because the control parameters are not optimized based on the interaction between each Magnus rotor, significant overlap is still observed in the pressure zones of the Magnus rotors. In a third example, as described above with respect to the method for controlling a system for wind propulsion equipment deployed on a vessel, control parameters are optimized based on the interaction between each Magnus rotor. Consequently, the rotational speed of the first Magnus rotor is optimized to be reduced to 150 revolutions per minute, and the rotational speed of the second Magnus rotor is optimized to be 130 revolutions per minute. This reduction in the rotational speed of the Magnus rotors indicates a lack of overlap between the pressure zones of the two Magnus rotors, significantly improving the efficiency of the Magnus rotors and reducing fuel consumption.

[0096] The present specification also relates to a method for controlling a Magnus rotor arranged on a vessel, the method comprising:

[0097] - providing pressure information from at least a first pressure sensor, the pressure information being a pressure distribution along a path of the first pressure sensor, wherein

[0098] - a first pressure sensor is arranged on the surface of the Magnus rotor; and

[0099] - a first pressure sensor is arranged at a first height H1 relative to the deck of the vessel;

[0100] - interpolating and extrapolating the pressure distribution on the surface of the Magnus rotor based on the pressure information from at least the first pressure sensor;

[0101] -Provide angular position information of the Magnus rotor from a rotary encoder;

[0102] - estimating the apparent wind angle based on the angular position information and the estimated pressure distribution on the surface of the Magnus rotor;

[0103] - Calculate the wind speed u by:

[0104] The air density ρ is calculated based on the atmospheric pressure p and temperature T using equation (8), where the atmospheric pressure is approximated by using a dedicated sensor. In equation (8), R (比) is the specific gas constant of dry air,

[0105]

[0106] - calculating the maximum dynamic pressure q on the surface of the Magnus rotor by subtracting the atmospheric pressure from the maximum pressure on the surface of the Magnus rotor; and

[0107] - Calculate the wind speed u using equation (9),

[0108]

[0109] - Use the estimated apparent wind angle to determine the optimal rotation direction of the Magnus rotor;

[0110] - using the calculated wind speed to determine an initial approximation of the optimal rotational speed for the Magnus rotor; and

[0111] - A closed-loop control method is used to operate the Magnus rotor at a rotor-specific optimal rotation per minute, where the feedback includes the internal and external pressure distribution.

[0112] The present description also relates to another method for controlling a Magnus rotor arranged on a vessel, the method comprising:

[0113] - measuring the Magnus rotor forces by combining plastic bending measurements and displacement measurements of a bearing arranged at the connection between the Magnus rotor and the base of the Magnus rotor;

[0114] - Using a closed-loop control method to operate the Magnus rotor at a rotor-specific optimal rotations per minute, where the feedback includes measured Magnus rotor forces.

[0115] Therefore, in the case of using a Magnus rotor on a ship, it is also possible to control the Magnus rotor by using only the measured Magnus rotor force, without using the pressure information explained in the above method.

[0116] The Magnus rotating body force F generated by the Magnus rotating body m is counteracted by the forces from the upper bearing and lower support points arranged in the Magnus rotor support structure. While counteracting the Magnus force, the Magnus rotor may experience plastic bending and displacement of the support points. It is worth noting that the upper bearing provides a reaction force F mbTo limit the plastic bending of the Magnus rotor. Here, the Magnus rotor undergoes plastic bending, which causes a measurable strain ΔL / L o , where L o The length change ΔL is the specified reference length to be measured after undergoing plastic bending. The measurement system needs to be calibrated to understand the correlation between the upper support load and the strain. This correlation value is called sensitivity. Sensitivity S se Given by equation (10),

[0117]

[0118] Among them F mb is the measured or known upper bearing force, ΔL / L o is the corresponding strain value. Then, when the sensitivity is known, the upper support force is obtained by multiplying the sensitivity by the measured strain value. F mb It has a linear relationship with the strain value.

[0119] In addition, the displacement of the lower support point is subjected to the force F calculated using equation (11) lb Constraints,

[0120] F lb =k lb x(11);

[0121] where x is the displacement of the lower support point, k lb is the calibrated measured value of the spring constant for the lower support point. K lb is a function of displacement x. It is worth noting that the total Magnus force should be F mb and F lb The method also includes using the measured Magnus rotor forces as feedback for optimizing the operation of the Magnus rotor. Notably, strain-based measurements of the Magnus rotor forces can advantageously be used to cross-validate pressure-based measurements. Furthermore, the amplitude of plastic bending and displacement observed in the Magnus rotor is very small. Therefore, a complex measurement arrangement is employed (such as an arrangement comprising the electrical connection of two strain gauge resistance bridges mounted at opposite ends of the Magnus rotor) to generate an amplified strain signal. Advantageously, the diametrically opposed measurements from such a sensor cancel out the effects of thermal expansion in the Magnus rotor.

[0122] The present disclosure uses the numbering symbols (1), (2), (3), (4), (5), (6), (7), (8), (9), (10), and (11) for equations. Equations (1), (5), and (8) are used to calculate the air density value for each corresponding embodiment. Equations (2), (6), and (9) are used to calculate the wind speed for each corresponding embodiment. Equations (3) and (10) are used to calculate the sensitivity value for the embodiment related to the Magnus rotor, and equation (7) is used to calculate the sensitivity value for the airfoil. Equations (4) and (11) are used to calculate the force F for the corresponding embodiment. lb .

[0123] The present disclosure also provides a vessel comprising at least two wind propulsion devices, each wind propulsion device comprising at least a first pressure sensor, wherein the first pressure sensor is arranged on a surface of the wind propulsion device at a first height H1 relative to a deck of the vessel, and the vessel is further equipped with an apparatus for performing the method described above. The embodiments and variations explained above are applicable to the vessel mutatis mutandis.

[0124] The present disclosure also provides a software product recorded on a non-transitory machine-readable data storage medium, wherein the software product can be executed on computing hardware, and the software product is used to implement the method for controlling a wind propulsion device arranged on a vessel as described above.

[0125] Detailed description of the drawings

[0126] Reference Figure 1 , shows a diagram of the steps of a method 100 for controlling a wind propulsion device arranged on a vessel according to an embodiment of the present disclosure. In step 102, pressure information is provided from at least a first pressure sensor, which is arranged on the surface of the wind propulsion device at a first height H1 relative to the deck of the vessel. In step 104, the pressure distribution on the surface of the wind propulsion device is estimated based on the pressure information from at least the first pressure sensor. In step 106, angular position information of the wind propulsion device is provided. In step 108, the apparent wind angle is estimated based on the angular position information of the wind propulsion device and the estimated pressure distribution on the surface of the wind propulsion device. In step 110, the estimated apparent wind angle is used to determine an initial approximation for a control parameter. In step 112, the estimated pressure distribution is used as feedback in a closed-loop control method to optimize the control parameters of the wind propulsion device.

[0127] Steps 102 and 116 are merely illustrative, and other alternatives may be provided in which one or more steps are added, one or more steps are removed, or one or more steps are provided in a different order without departing from the scope of the claims herein.

[0128] Reference Figure 2 , shows a block diagram of a closed-loop control method for optimizing control parameters according to an illustration of the present disclosure. Figure 1 As described above, in step 110, an estimated apparent wind angle is used to determine an initial approximate value for a control parameter, wherein the apparent wind angle is estimated based on angular position information of the wind propulsion device and an estimated pressure distribution on the surface of the wind propulsion device. In step 202, the initial approximate value for the control parameter is implemented on the wind propulsion device. Subsequently, in step 204, after the control parameter is implemented, pressure information is provided from at least a first pressure sensor, which is arranged on the surface of the wind propulsion device at a first height H1 relative to the deck of the vessel. In step 206, the pressure distribution on the surface of the wind propulsion device is estimated based on the pressure information from at least the first pressure sensor. Thereafter, in step 112, the estimated pressure distribution on the surface of the wind propulsion device is used as feedback in a closed-loop control method to determine another approximate value for the control parameter, thereby optimizing the control parameter of the wind propulsion device.

[0129] Reference Figure 3 FIG. 3 shows a Magnus rotor 300 as a wind propulsion device according to an embodiment of the present disclosure. As shown, a first pressure sensor 302 is arranged on the surface of the Magnus rotor 300 at a first height H1 relative to the ship's deck. A second pressure sensor 304 is arranged at a second height H2 relative to the ship's deck. Notably, the difference between the first height H1 and the second height H2 is at least 20% of the total height H of the Magnus rotor. Similarly, a third pressure sensor 306 is arranged at a third height H3 relative to the ship's deck, and the differences between the first height H1, the second height H2, and the third height H3 are each at least 10% of the total height H of the Magnus rotor. It should be understood that as the Magnus rotor 300 rotates, the pressure sensors 302, 304, and 306, which rotate with the Magnus rotor 300, measure pressure information associated with different areas on the surface of the Magnus rotor 300.

[0130] Reference Figure 4 , shows the inflow of wind at the Magnus rotor 400. It is noteworthy that, as shown in the figure, the inflow of wind is significantly changed due to the Magnus rotor 400. The lines in the figure represent velocity contours.

[0131] Reference Figure 5 , a schematic diagram showing pressure distribution at different heights of the Magnus rotor 500 due to non-uniform inflow. The lines in the figure represent pressure contours.

[0132] Reference Figure 6FIG. 6 illustrates a wing sail 600 as a wind propulsion device according to an embodiment of the present disclosure. Notably, wing sail 600 has a curved structure with a convex side 602 and a concave side 604. Due to the airfoil structure of sail 600 and the movement of wind along the airfoil, lower pressure is observed on convex side 602 of sail 600 compared to pressure on concave side 604 of sail 600. As shown, sail 600 has a leading edge 606 and a trailing edge 608, with the leading edge directly penetrating the wind flow. Notably, sail 600 includes different chords, such as chord 610, chord 612, and chord 614, at different heights. Furthermore, a first pressure sensor 616 is disposed on the surface of sail 600 at a first height H1 relative to the deck of the vessel. Furthermore, a second pressure sensor 618 is disposed on the surface of sail 600 along the same chord 610 as first pressure sensor 616, at a height H1 relative to the deck of the vessel.

[0133] Reference Figure 7 , shows a graph illustrating the relationship between rotational speed and net benefit when a wind propulsion device is implemented as a Magnus rotor according to an embodiment of the present disclosure. The X-axis of the graph represents rotational speed, and the Y-axis represents the net benefit of the Magnus rotor. It is worth noting that the net benefit refers to the energy saved or reduced fuel consumption due to the propulsion provided by the Magnus rotor. As shown in the graph, the net benefit increases with increasing rotational speed of the Magnus rotor until an inflection point, after which the energy consumed to generate rotation in the Magnus rotor exceeds the benefit gained from the resulting propulsion.

[0134] Reference Figure 8 , shows the forces acting on the Magnus rotor 800. It is worth noting that the Magnus force F is generated due to the rotation of the Magnus rotor 800. m Force F m The Magnus rotor 800 is counteracted by forces from an upper bearing disposed in the Magnus rotor 800 and a lower support point disposed at the connection between the Magnus rotor 800 and the base portion of the Magnus rotor 800. While counteracting the Magnus force, the Magnus rotor 800 may experience plastic bending and displacement of the bearing. It is worth noting that the upper bearing provides a reaction force F mb To limit the plastic bending of the Magnus rotor 800. In addition, the displacement of the bearing arranged at the lower support point (ie at the connection between the Magnus rotor 800 and the base of the Magnus rotor) is subjected to the force F lb constraints.

[0135] Reference Figure 9, a diagram illustrating steps of a method 900 for controlling a system for wind propulsion devices according to an embodiment of the present disclosure is shown. Here, the method 900 is described with respect to a first wind propulsion device and a second wind propulsion device, wherein the first propulsion device is arranged in an upwind position on a vessel compared to the second propulsion device. In step 902, a method for controlling wind propulsion devices arranged on a vessel (such as Figure 1 The control parameters for the first propulsion device are optimized using the method 100 described in

[15] . At step 904, the control parameters for the second propulsion device are optimized using the method 100 described above. At step 906, the interaction between the pressure profiles of the first propulsion device and the second propulsion device is compared to determine the impact of the first propulsion device on the pressure profile of the second propulsion device. At step 908, the overall efficiency of the system of wind propulsion devices is determined, and the results are provided as feedback at step 906 to optimize the control parameters of the first propulsion device and the second propulsion device.

[0136] Reference Figure 10 , shows schematic diagrams of a vessel in different examples of optimizing control parameters according to an exemplary embodiment of the present disclosure. The vessel includes a first Magnus rotor and a second Magnus rotor arranged at different locations along the length of the vessel. In a first example 1010, control parameters of the Magnus rotors (such as the rotational speed) are not optimized based on the method 100 for controlling a wind propulsion device described above. In this example 1010, the rotational speeds of the two Magnus rotors are determined to be equal, for example, 180 revolutions per minute. A significant overlap is observed between the pressure regions of the Magnus rotors in this example 1010. In a second example 1020, control parameters are optimized based on the method 100 for controlling a wind propulsion device described above. Based on this method 100, the rotational speed of the second Magnus rotor is optimized to 130 revolutions per minute. This optimization results in a significant reduction in fuel consumption. However, because the control parameters are not optimized based on the interaction between each Magnus rotor, significant overlap is still observed in the pressure regions of the Magnus rotors. In a third example 1030, as described above with respect to method 900 for controlling a system for wind propulsion equipment disposed on a vessel, the control parameters are optimized based on the interaction between each Magnus rotor. Thus, the rotational speed of the first Magnus rotor is optimized to be reduced to 150 revolutions per minute, and the rotational speed of the second Magnus rotor is optimized to be 140 revolutions per minute. This reduction in the rotational speed of the Magnus rotors indicates a lack of overlap between the pressure regions of the two Magnus rotors, thereby significantly improving the efficiency of the Magnus rotors and reducing fuel consumption.

[0137] The embodiments of the present disclosure described above may be modified without departing from the scope of the present disclosure as defined by the appended claims. Expressions such as "comprising," "including," "incorporating," "having," and the like used to describe and claim the present disclosure are intended to be interpreted in a non-exclusive manner, i.e., allowing for the presence of items, components, or elements not expressly described. References to the singular are also to be interpreted as referring to the plural.

Claims

1. A method for controlling a Magnus rotor (300) arranged on a vessel, the method comprising: - providing pressure information relating to different areas of the cross section from a first pressure sensor (302), which is arranged on the surface of the Magnus rotor at a first height H1 relative to the deck of the vessel; - estimating the pressure distribution on the surface of the Magnus rotor based on the pressure information from the first pressure sensor, and - Using the estimated pressure distribution as feedback in a closed-loop control method to optimize control parameters of the Magnus rotor.

2. The method according to claim 1, wherein The method further includes - Provides angular position information of the Magnus rotator; - estimating an apparent wind angle based on the angular position information of the Magnus rotator and the estimated pressure distribution on the surface of the Magnus rotator, and - Using the estimated apparent wind angle to determine initial approximate values for control parameters.

3. The method according to claim 2, wherein - providing said angular position information by an angular position measuring device; - the control parameters include the optimal rotation speed of the Magnus rotor; The method further includes - Calculate the wind speed u by the following, - Calculate the air density ρ based on the atmospheric pressure p and temperature T using equation (1), where The atmospheric pressure is approximated by the pressure at the rear side of the rotating body or by using a dedicated sensor. In the equation (1), R (比) is the specific gas constant of dry air, （1）； - calculating the maximum dynamic pressure q on the surface of the Magnus rotor by subtracting the atmospheric pressure from the maximum pressure on the surface of the Magnus rotor; and - Calculate the wind speed u using equation (2), （2）； - using the estimated apparent wind angle to determine an optimal rotation direction of the Magnus rotor; and - Using the calculated wind speed in addition to the estimated apparent wind angle to determine the initial approximate value for a control parameter.

4. The method of claim 3, further comprising providing pressure information from at least a second pressure sensor (304), wherein - the second pressure sensor is arranged at a second height H2 relative to the deck of the vessel; - the difference between the first height H1 and the second height H2 is at least 20% of the total height H of the Magnus rotor; and - performing an estimation of the pressure distribution by interpolating and extrapolating the pressure distribution on the surface of the Magnus rotor based on the pressure information from at least the first pressure sensor (302) and the second pressure sensor.

5. The method according to claim 4, further comprising arranging at least a third pressure sensor (306) on the surface of the Magnus rotor, wherein The third pressure sensor is arranged at a third height H3 relative to the deck of the vessel, and a difference between the first height H1, the second height H2, and the third height H3 is at least 10% of the total height H of the Magnus rotor.

6. The method according to any one of claims 3 to 5, further comprising arranging a plurality of another pressure sensors on the surface of the Magnus rotor, wherein: Each further pressure sensor is arranged at a given height relative to the deck of the vessel, and the difference between the heights of each of the pressure sensors is at least 5% of the total height H of the Magnus rotor, and wherein the number of further pressure sensors is at least four.

7. The method according to claim 5, wherein: The first pressure sensor (302), the second pressure sensor (304) and the third pressure sensor (306) are arranged along a line substantially parallel to the rotation axis of the Magnus rotor.

8. The method according to claim 5, wherein The first pressure sensor (302), the second pressure sensor (304) and the third pressure sensor (306) are arranged along a spiral line.

9. The method according to any one of claims 3 to 5, further comprising - measuring the Magnus rotor forces by combining plastic bending measurements and displacement measurements of a bearing arranged at the connection between the Magnus rotor and the base of the Magnus rotor; - Using the measured Magnus rotor forces as feedback for optimizing the operation of the Magnus rotor.

10. A method for controlling a system of a Magnus rotor (300) arranged on a vessel, the method comprising - optimizing the control parameters of each Magnus rotor according to the method of any one of claims 1 to 9; and - Optimizing the overall efficiency of the Magnus rotors using closed-loop control by measuring individual differences in performance and taking into account the interactions between each Magnus rotor; in, The Magnus rotors are arranged at different positions on the vessel relative to the length of the vessel.

11. A vessel comprising at least two Magnus rotators (300), each Magnus rotator comprising a first pressure sensor (302), wherein: The first pressure sensor is arranged on the surface of the Magnus rotor at a first height H1 relative to the deck of the vessel, and the vessel is further equipped with means for performing the method of any one of claims 1 to 10.

12. A software product recorded on a non-transitory machine-readable data storage medium, wherein: The software product is executable on computing hardware for implementing the method according to any one of claims 1 to 10 .

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