A Wave Adaptive Ship Propeller Control System and Control Method

Abstract

The present invention relates to a wave adaptive ship propeller control system and a control method. The control system includes a control unit system, a physical unit system, and a sensor unit system; the control unit system includes a signal acquisition and processing subsystem, a state estimation filter, and a controller; the physical unit system includes a winch driver, a winch mechanism, a lifting platform mechanism, and a propulsion system. The propulsion system is arranged on the platform in the lifting platform mechanism, and the winch driver drives the platform to lift through the winch mechanism to realize the lifting of the propulsion system; the sensor unit system includes a wave height sensor, a multi-turn absolute encoder, and a gyroscope. The present invention comprehensively utilizes the sensor unit system and the state estimation method based on Kalman filtering of the state estimation filter to realize dynamic motion control. The control method is a feedback control based on the propeller operation depth, the position information of the lifting platform, and the ship attitude signal, and accurately realizes the real-time adjustment of the propeller operation depth.

Description

Technical Field

[0001] The present invention relates to the technical field of ship propulsion system control, and in particular to a wave adaptive ship propeller control system and a control method. Background Art

[0002] The propeller is the most commonly used structure of a ship propeller. It rotates in water by the propeller blades, converting the rotational power of the engine into the propulsion force of the ship. Based on the need to ensure propulsion efficiency and protect the propeller, the operating depth of the propeller should be maintained within a certain range, neither too deep nor too shallow.

[0003] For small and medium-sized ships driven by motors or hydraulic motors, especially unmanned ships, the hull size and weight are very small, and the draft is relatively shallow. When sailing at sea, affected by waves, the hull will generate motions such as pitching and heaving. If the vertical heaving and longitudinal pitching amplitudes of the hull are too large, the immersion depth of the propeller will change, and the propeller may partially or completely emerge from the water. In this state, the propeller cannot generate sufficient thrust, or even no thrust acts on the hull, resulting in the ship being in an intermittent out-of-control state, unable to maintain the established course, speed and trajectory, affecting the safety of ship navigation; in addition, the intermittent emergence and immersion of the propulsion propeller will cause severe fluctuations in the load of the transmission mechanism and the ship's main engine, resulting in fatigue damage and main engine damage, posing a great threat to the safety of the equipment.

[0004] Currently, most of the propellers used on ships are fixedly installed. Large ships mostly rely on the ballast system to adjust the ship's draft and longitudinal and transverse inclinations. Small and medium-sized ships cannot adjust the immersion depth of the propeller as needed. Summary of the Invention

[0005] The applicant of the present invention aims at the above-mentioned disadvantages in the existing production technology, and provides a wave adaptive ship propeller control system and a control method, so as to achieve the purpose of dynamically adjusting the operating depth of the propeller, ensuring that the immersion depth of the propeller is always maintained at the optimal operating depth, and further ensuring the ship propulsion efficiency and navigation safety.

[0006] The technical solution adopted by the present invention is as follows:

[0007] A wave adaptive ship propeller control system includes:

[0008] A control unit system, including a signal acquisition and processing subsystem, a state estimation filter and a controller, which are connected by electrical signals;

[0009] A physical unit system, including a winch driver, a winch mechanism, a lifting platform mechanism and a propulsion system. The propulsion system is arranged on the platform in the lifting platform mechanism, and the winch driver drives the platform to lift through the winch mechanism to realize the lifting of the propulsion system;

[0010] The sensor unit system includes a wave height sensor, a multi-turn absolute encoder, and a gyroscope.

[0011] Further improved technical solution:

[0012] The wave height sensor is used to measure the actual working depth information of the propeller. The multi-turn absolute encoder is used to obtain the position information of the lifting platform. The gyroscope is used to obtain the longitudinal motion attitude signal of the ship, and the attitude signal includes heave displacement and pitch angle.

[0013] The signal acquisition and processing subsystem receives the propeller working depth, platform position information, and ship attitude signal monitored by the sensor unit system, performs preprocessing and data fusion, eliminates the corresponding error signals, obtains useful information and performs effective combination to form new effective information.

[0014] The state estimation filter is based on the Kalman filtering method. Using the new effective information obtained from the signal acquisition and processing subsystem and the state estimation value at the previous moment, and with the help of the state transition equation of the system itself, it calculates the estimated value of the current working depth of the propeller according to the recurrence formula.

[0015] The controller uses the deviation between the estimated state of the current working depth of the propeller and the desired optimal working depth state as the input quantity, performs PID control, gives a control command and sends it to the winch driver to realize real-time lifting dynamic adjustment of the platform, so that the working depth of the propeller always meets the working requirements.

[0016] The control method of the above wave adaptive ship propulsion control system includes the following steps:

[0017] S1. The wave height sensor, multi-turn absolute encoder, and gyroscope respectively obtain the actual working depth information of the propeller, the position information of the platform, and the ship attitude signal, and send them to the signal acquisition and processing subsystem;

[0018] S2. The signal acquisition and processing subsystem performs preprocessing and data fusion to form new effective information and transmits it to the state estimation filter;

[0019] S3. The state estimation filter is based on the Kalman filtering method. According to the new effective information and the state estimation value at the previous moment, it calculates the estimated value of the current working depth of the propeller and transmits it to the controller;

[0020] S4. The controller generates a platform height control command based on the deviation between the estimated value of the current working depth and the desired working depth value, and transmits it to the winch driver;

[0021] S5. The winch driver drives the winch mechanism to adjust the platform height by winding and unwinding the steel cable, and then drives the propulsion system to change the immersion depth of the propeller, so that the propeller is at the optimal working depth.

[0022] Further improved technical solution:

[0023] Specifically in step S3, the heave (vertical motion) displacement z and pitch angle θ of the ship's longitudinal motion are obtained through the Kalman filtering method. By fusing the propeller operation depth observation values obtained by the signal acquisition and processing subsystem, and according to the discrete state equation and prediction equation, the predicted value of the actual propeller operation depth is further obtained, and the current estimated propeller operation depth state is obtained.

[0024] Discrete state equation:

[0025] X(k + 1) = φ Z (k)X(k) + Γ Z (k)W(k)

[0026] In the formula, X(k) and X(k + 1) represent the state quantities at times k and k + 1;

[0027] φ Z is the longitudinal one-step transfer matrix, T s is the sampling period, obtained according to the sampling theorem and combined with the actual analysis frequency band;

[0028] Γ Z is the system longitudinal motion noise driving matrix,

[0029] W(k) is the system excitation noise sequence;

[0030] Discrete prediction equation:

[0031] Y(k) = C Z X(k + 1) + V(k + 1)

[0032] In the formula, Y(k) represents the predicted physical quantity at time k, and V(k + 1) is the measurement noise sequence at time k + 1

[0033]

[0034] Specifically, the continuous state equation and prediction equation

[0035] According to the ship's longitudinal motion, including the ship's heave (vertical motion) and pitch, the longitudinal motion differential equation is established as follows:

[0036]

[0037] In the formula, z, respectively represent the hull heave (vertical motion) displacement, velocity, and angular velocity, m, m / s, m / s 2 ;

[0038] θ, respectively represent the pitch angle, angular velocity, and angular acceleration of the hull, in rad, rad / s, rad / s 2 ;

[0039] m represents the mass of the hull, in kg; I5 represents the pitch moment of inertia, in kg·m 2 ;

[0040] a 33 represents the added mass, a 55 represents the mass moment, a 35 、a 53 represents the moment of inertia;

[0041] b 33 、b 53 represent the damping coefficient, b 55 、b 35 represent the damping moment coefficient;

[0042] c 33 、c 53 represent the restoring force coefficient, c 55 、c 35 represent the restoring moment coefficient;

[0043] Z3 represents the heaving (swaying) disturbing force, in kg·m / s 2 ; M5 represents the pitch disturbing moment, in kg·m 2 / s 2 。

[0044] Let the state variable the wave disturbance W T =[Z3, M5], and express the longitudinal motion differential equation in matrix form as follows:

[0045]

[0046]

[0047]

[0048]

[0049] Then the continuous state equation is expressed as follows:

[0050]

[0051] In the formula, A Z =E -1 M, B Z =E -1 N.

[0052] The heaving position and pitching angle are the predicted physical quantities, and the equations for the predicted physical quantities are expressed as follows:

[0053] Y = C Z X + V

[0054]

[0055] Where V is the two-dimensional measurement noise.

[0056] Specifically, in step S4, the controller uses the deviation e(t) between the current operation depth estimation state c(t) and the desired optimal operation depth state r(t) as the input quantity for PID control:

[0057] e(t) = r(t) - c(t)

[0058]

[0059] Where K p , T i , T d are the controller parameters, and u(t) is the control output of the controller.

[0060] The beneficial effects of the present invention are as follows:

[0061] The present invention provides a thruster control system for medium and small-sized ships without a ballast system, especially for medium and small-sized ships driven by motors or hydraulic motors and unmanned ships when sailing in high sea states. When paired with the ship propulsion system, it can dynamically adjust the propeller operation depth in real time, ensuring that the propeller immersion depth is always maintained at the optimal operation depth, thereby ensuring the ship propulsion efficiency and navigation safety.

[0062] The present invention also has the following advantages:

[0063] (1) The present invention comprehensively utilizes the sensor unit system and the state estimation filter based on the Kalman filter state estimation method to achieve dynamic motion control. The control method is a feedback control based on the propeller operation depth, the lifting platform position information, and the ship attitude signal. In order to compensate for static environmental interference, the integral theorem is appropriately introduced to accurately achieve real-time adjustment of the propeller operation depth.

[0064] (2) In the present invention, the signal acquisition and processing subsystem preprocesses and fuses the data collected by the sensor unit system, eliminates the corresponding error signals, obtains useful information and combines it effectively, avoiding the interference introduced by measurement noise in the measurement values of the sensor unit system.

[0065] (3) In the present invention, the signal acquisition and processing subsystem preprocesses and fuses the acquired information to form new valid information, which is transmitted to the state estimation filter; the state estimation filter, based on the Kalman filtering method, calculates the current estimated value of the propeller operation depth according to the new valid information and the state estimation value at the previous moment, and transmits it to the controller; the controller generates a platform height control command based on the deviation between the current estimated value of the operation depth and the expected value of the operation depth, and transmits it to the winch driver; the winch driver drives the winch mechanism to adjust the platform height by winding and unwinding the steel cable, thereby driving the propulsion system and changing the immersion depth of the propeller, so as to ensure that the propeller is at the optimal operation depth.

[0066] (4) The present invention does not need to save and utilize all past measurement data, reduces the requirements for computer storage and computing volume, facilitates real-time processing, is easy to implement, and has high controllability and stability. Description of the Drawings

[0067] Figure 1 is the structural block diagram of the control system of the present invention.

[0068] Figure 2 is the structural block diagram of the control unit system in the present invention.

[0069] Figure 3 is the structural schematic diagram of the physical unit system in the present invention.

[0070] Figure 4 is the structural schematic diagram of the propulsion system in the present invention.

[0071] Among them: 100, hull; 101, gyroscope; 200, calm water surface; 301, winch driver; 302, winch drive shaft; 303, cable winding and unwinding mechanism; 304, multi-turn absolute encoder, 305, base; 306, slide rail; 307, platform counterweight; 308, platform; 309, steel cable; 310, fixed pulley; 401, propeller driver; 402, steering mechanism; 403, steering driver; 404, shaft tube; 405, wave height sensor; 406, propeller; 407, propeller immersion depth; 408, right-angle transmission housing; 409, vertical transmission shaft; 410, horizontal transmission shaft. Detailed Embodiment

[0072] The following combines the drawings to illustrate the detailed embodiment of the present invention.

[0073] As shown in the attached Figure 1 and 2As shown in the figure, a wave adaptive ship propulsion control system includes a control unit system, a physical unit system, and a sensor unit system, which are interconnected; the control unit system includes a signal acquisition and processing subsystem, a state estimation filter, and a controller, which are connected by electrical signals; the physical unit system includes a winch driver 301, a winch mechanism, a lifting platform mechanism, and a propulsion system. The propulsion system is arranged on the platform in the lifting platform mechanism. The winch driver 301 drives the platform 308 to lift through the winch mechanism to realize the lifting of the propulsion system; the sensor unit system includes a wave height sensor 405, a multi-turn absolute encoder 304, and a gyroscope 101. The wave height sensor 405 is arranged on the propulsion system, the multi-turn absolute encoder 304 is arranged on the lifting platform mechanism, and the gyroscope 101 is arranged on the hull 100.

[0074] The wave height sensor 405 is used to measure the actual working depth information of the propeller. The multi-turn absolute encoder 304 is used to obtain the position information of the lifting platform. The gyroscope 101 is used to obtain the longitudinal motion attitude signal of the ship. The attitude signal includes heave displacement and pitch angle.

[0075] The signal acquisition and processing subsystem receives the propeller working depth, platform position information, and ship attitude signal monitored by the sensor unit system, performs preprocessing and data fusion, eliminates the corresponding error signals, obtains useful information and performs effective combination to form new effective information.

[0076] The state estimation filter, based on the Kalman filtering method, uses the new effective information obtained from the signal acquisition and processing subsystem and the state estimation value at the previous moment, and calculates the current working depth estimation value of the propeller according to the recurrence formula with the help of the state transition equation of the system itself.

[0077] The controller uses the deviation between the current working depth estimation state of the propeller and the desired optimal working depth state as the input quantity, performs PID control, gives a control command to the winch driver 301, and realizes real-time lifting dynamic adjustment of the platform, so that the working depth of the propeller always meets the working requirements.

[0078] Since the measured values of the sensor unit system contain interference introduced by measurement noise (determined by the sensor type and measurement method), therefore, the data collected by the sensor unit system is first preprocessed and data fused by the signal acquisition and processing subsystem to eliminate the corresponding error signals and obtain effective information. After the state estimation filter performs state estimation and calculates the current working depth estimation value of the propeller, the estimated value of the current working depth of the propeller is transmitted to the controller to realize closed-loop feedback control.

[0079] The physical unit system includes a winch driver 301, a winch mechanism, a lifting platform mechanism, and a propulsion system. The propulsion system is arranged on a platform 308 in the lifting platform mechanism. The winch driver 301 drives the platform 308 to lift through the winch mechanism, thereby realizing the lifting of the propulsion system.

[0080] As shown in the appendix Figure 3 As shown, the winch mechanism includes a cable winding and unwinding mechanism 303. The cable winding and unwinding mechanism 303 is connected to one end of a steel cable 309, and the other end of the steel cable 309 is fixedly connected to the platform 308. The winch driver 301 drives the cable winding and unwinding mechanism 303 to rotate through a winch drive shaft 302, drives the steel cable 309 to wind and unwind, and thereby realizes the lifting of the platform 308.

[0081] The lifting platform mechanism includes a base 305 fixed on a hull 100, a platform 308 arranged on the base 305, and a winch mechanism for adjusting the height of the platform 308; the winch mechanism drives the platform 308 to lift through a fixed pulley 310 and a steel cable 309.

[0082] Sliding rails 306 are arranged on the side walls of the base 305, and the platform 308 moves up and down along the sliding rails 306 when lifting. A platform counterweight 307 is arranged at one end of the platform 308 away from the propulsion system.

[0083] The propulsion system includes a drive assembly, a transmission assembly, and a propulsion assembly. The drive assembly is fixed on the platform 308. The transmission assembly passes through the platform body 308 and is respectively connected to the drive assembly and the propulsion assembly at both ends.

[0084] As shown in the appendix Figure 4 As shown, the transmission assembly includes a shaft tube 404 and a vertical transmission shaft 409 arranged inside the shaft tube 404. A wave height sensor 405 is installed on the side wall of the shaft tube 404. The propulsion assembly includes a propeller 406 and a right-angle transmission housing 408; the propeller 406 is in transmission connection with the vertical transmission shaft 409 through a horizontal transmission shaft 410. The horizontal transmission shaft 410 penetrates into the right-angle transmission housing 408, and the lower end of the vertical transmission shaft 409 penetrates into the right-angle transmission housing 408. The right-angle transmission housing 408 is fixedly connected to the shaft tube 404.

[0085] The drive assembly includes a rudder drive 403 and a propeller drive 401. The rudder drive 403 drives the shaft tube 404 to rotate, and at the same time drives the entire propulsion assembly below to rotate, realizing the rudder drive function; the propeller drive 401 drives the vertical transmission shaft 409 and the horizontal transmission shaft 410 to rotate to realize the rotational drive of the propeller 406, realizing the propulsion function of the hull 100. The two rotational degrees of freedom operate independently.

[0086] The rudder drive 403 drives the shaft tube 404 and the right-angle transmission housing 408 to rotate integrally through a rudder mechanism 402.

[0087] Further, the wave height sensor 405 is installed on the side wall of the shaft tube 404, and the multi-turn absolute encoder 304 is arranged on the cable winching mechanism 303.

[0088] Operating principle of the physical unit system:

[0089] Under normal conditions, i.e., on the calm water surface 200, the propeller 406 in the propulsion system is at the designed height, which ensures that the immersion depth 407 of the propeller is in the optimal operating depth state; when the hull 100 is affected by waves and forms a wavy liquid surface, resulting in the immersion depth of the propeller 406 being less than the lower limit of the operating depth, the winch driver 301 controls the winch mechanism to release the steel cable 309, and the platform 308 slides down along the slide rail 306, driving the propulsion system to descend and maintaining it at the optimal operating depth; when the immersion depth exceeds the upper limit of the operating depth, the winch mechanism is controlled to recover the steel cable 309, the platform 308 slides up along the slide rail 306, driving the propulsion system to lift, and the propeller 406 returns to the designed height.

[0090] The control method of the above wave adaptive ship propulsion control system includes the following steps:

[0091] S1. The wave height sensor 405, the multi-turn absolute encoder 304, and the gyroscope 101 respectively obtain the actual operating depth information of the propeller, the position information of the platform, and the attitude signal of the ship, and send them to the signal acquisition and processing subsystem.

[0092] S2. The signal acquisition and processing subsystem performs preprocessing and data fusion to form new valid information and transmits it to the state estimation filter.

[0093] S3. Based on the Kalman filtering method, the state estimation filter calculates the current estimated operating depth value of the propeller according to the new valid information and the state estimation value at the previous moment, and transmits it to the controller.

[0094] The heave (vertical motion) displacement z and pitch angle θ of the ship's longitudinal motion are obtained through the Kalman filtering method. By fusing the observed values of the propeller operating depth obtained by the signal acquisition and processing subsystem, according to the discrete state equation and prediction equation, the predicted value of the actual operating depth of the propeller is further obtained, and the current estimated operating depth state of the propeller is obtained.

[0095] Specifically:

[0096] According to the ship's longitudinal motion, including ship heave (vertical motion) and pitch, the following differential equation of longitudinal motion is established:

[0097]

[0098] In the formula, z, respectively represent the heave (vertical motion) displacement, velocity, and angular velocity of the hull, m, m / s, m / s2 ;

[0099] θ, respectively represent the pitch angle, angular velocity, and angular acceleration of the hull, in rad, rad / s, rad / s 2 ;

[0100] m represents the mass of the hull, in kg; I5 represents the pitch moment of inertia, in kg·m 2 ;

[0101] a 33 represents the added mass, a 55 represents the mass moment, a 35 , a 53 represents the moment of inertia;

[0102] b 33 , b 53 represent the damping coefficient, b 55 , b 35 represent the damping moment coefficient;

[0103] c 33 , c 53 represent the restoring force coefficient, c 55 , c 35 represent the restoring moment coefficient;

[0104] Z3 represents the heave (sway) disturbing force, in kg·m / s 2 ; M5 represents the pitch disturbing moment, in kg·m 2 / s 2 .

[0105] Let the state variable the wave disturbance W T = [Z3, M5], and express the longitudinal motion differential equation in matrix form as follows:

[0106]

[0107]

[0108]

[0109]

[0110] Then the continuous state equation is expressed as follows:

[0111]

[0112] In the formula, A Z = E -1 M, B Z = E -1 N.

[0113] The heaving position and pitching angle are the predicted physical quantities, and the equations for the predicted physical quantities are expressed as follows:

[0114] Y = C Z X + V

[0115]

[0116] where V is the two-dimensional measurement noise.

[0117] The discretized state equation:

[0118] X(k + 1) = φ Z (k)X(k) + Γ Z (k)W(k)

[0119] where X(k) and X(k + 1) represent the state quantities at times k and k + 1;

[0120] φ Z is the longitudinal one-step transition matrix, T s is the sampling period, obtained according to the sampling theorem in combination with the actual analysis frequency band;

[0121] Γ Z is the system longitudinal motion noise driving matrix,

[0122] W(k) is the system excitation noise sequence;

[0123] The state X(k + 1) to be estimated at time k + 1 is driven by the system noise sequence W(k), and the driving reason is described by the above state equation;

[0124] The discretized prediction equation:

[0125] Y(k) = C Z X(k + 1) + V(k + 1)

[0126] where Y(k) represents the predicted physical quantity at time k, and V(k + 1) is the measurement noise sequence at time k + 1.

[0127] S4. The controller generates a platform height control command based on the deviation between the current estimated value of the operation depth and the expected value of the operation depth, and transmits it to the winch driver 301.

[0128] Specifically, the controller uses the deviation e(t) between the current estimated state c(t) of the operation depth and the expected optimal operation depth state r(t) as the input quantity for PID control:

[0129] e(t) = r(t) - c(t)

[0130]

[0131] In the formula, K p , T i , T d are controller parameters, and u(t) is the control output of the controller.

[0132] S5. The winch driver 301 drives the winch mechanism to adjust the height of the platform 308 by winding and unwinding the steel cable 309, and then drives the propulsion system to change the immersion depth of the propeller 406, so that the propeller 406 is at the optimal working depth.

[0133] It should be noted that in this application, represents the first derivative of z with respect to z, represents the second derivative of z with respect to z; represents the first derivative of X with respect to X.

[0134] The above description is an explanation of the present invention, not a limitation of the invention. The scope defined by the present invention is referred to the claims, and any form of modification can be made within the protection scope of the present invention.

Claims

1. A control method for a wave adaptive ship propulsion control system, characterized in that: The wave adaptive ship propulsion control system includes: A control unit system, including a signal acquisition and processing subsystem, a state estimation filter, and a controller, which are connected by electrical signals; A physical unit system, including a winch driver (301), a winch mechanism, a lifting platform mechanism, and a propulsion system. The propulsion system is arranged on the platform (308) in the lifting platform mechanism. The winch driver (301) drives the platform (308) to lift through the winch mechanism to realize the lifting of the propulsion system; A sensor unit system, including a wave height sensor (405), a multi-turn absolute encoder (304), and a gyroscope (101); During operation, it includes the following steps: S1. The wave height sensor (405), the multi-turn absolute encoder (304), and the gyroscope (101) respectively obtain the actual operation depth information of the propeller, the position information of the platform, and the attitude signal of the ship, and send them to the signal acquisition and processing subsystem; S2. The signal acquisition and processing subsystem performs preprocessing and data fusion to form new effective information and transmits it to the state estimation filter; S3. The state estimation filter, based on the Kalman filtering method, calculates the current operation depth estimate of the propeller according to the new effective information and the state estimate value at the previous moment, and transmits it to the controller; S4. The controller generates a platform height control command based on the deviation between the current operation depth estimate value and the expected operation depth value, and transmits it to the winch driver (301); S5. The winch driver (301) drives the winch mechanism to adjust the height of the platform (308) by winding and unwinding the steel cable (309), thereby driving the propulsion system and changing the immersion depth of the propeller (406), so that the propeller (406) is at the optimal operation depth; Specifically in step S3, the heave displacement of the ship's longitudinal motion is obtained through the Kalman filtering method and the pitch angle , by fusing the observed value of the propeller operation depth obtained by the signal acquisition and processing subsystem, according to the discrete state equation and prediction equation, the predicted value of the actual propeller operation depth is further obtained, and the current estimated operation depth state of the propeller is obtained; The discretized state equation: In the formula, and represent k and k the state variables at the +1 moment; is the longitudinal one-step transition matrix, , is the sampling period, obtained according to the sampling theorem and by combining the actual analysis frequency band; It is the noise-driven array for the longitudinal movement of the system, ; is the system excitation noise sequence; The discretized prediction equation: In the formula, represents k the predicted physical quantity at time is k the measurement noise sequence at time +1.

2. The control method of the wave adaptive ship propulsion control system according to claim 1, characterized in that: The wave height sensor (405) is used to measure the actual operation depth information of the propeller. The multi-turn absolute encoder (304) is used to obtain the position information of the lifting platform (308). The gyroscope (101) is used to obtain the longitudinal motion attitude signal of the ship. The attitude signal includes heave displacement and pitch angle.

3. The control method of the wave adaptive ship propulsion control system according to claim 1, characterized in that: The signal acquisition and processing subsystem receives the propeller operation depth, platform position information, and ship attitude signal monitored by the sensor unit system, performs preprocessing and data fusion, eliminates the corresponding error signals, obtains useful information and performs effective combination to form new effective information.

4. The control method of the wave adaptive ship propulsion control system according to claim 3, characterized in that: The state estimation filter, based on the Kalman filtering method, uses the new effective information obtained from the signal acquisition and processing subsystem and the state estimate value at the previous moment, and calculates the current operation depth estimate of the propeller according to the state transition equation of the system itself and the recurrence formula.

5. The control method of the wave adaptive ship propulsion control system according to claim 1, characterized in that: The controller uses the deviation between the current operation depth estimation state of the propeller and the desired optimal operation depth state as the input quantity, performs PID control, gives a control command and sends it to the winch driver (301) to realize the real-time lifting dynamic adjustment of the platform (308), so that the operation depth of the propeller always meets the operation requirements.

6. The control method of the wave adaptive ship propulsion control system according to claim 1, characterized in that: The continuous state equation and prediction equation specifically, According to the longitudinal motion of the ship, including heave and pitch of the ship, the following longitudinal motion differential equation is established: In the formula, , , respectively represent the heave displacement, velocity, and angular velocity of the hull, ; , , respectively represent the hull pitching angle, angular velocity, and angular acceleration, ; Represents the hull mass, kg; Represents the pitching moment of inertia, kg·m 2 ; represents the added mass, represents the mass moment, , represents the moment of inertia; , represents the damping coefficient, , represents the damping moment coefficient; , represents the resilience coefficient, , represents the restoring moment coefficient; Indicates the heaving interference force, kg·m / s 2 ; Indicates the pitching interference moment, kg·m 2 / s 2 ; Let the state variable , ocean wave interference , and the longitudinal motion differential equation is expressed in matrix form as follows: The continuous state equation is expressed as follows: In the formula, ; The heave position and pitch angle are the predicted physical quantities, and the equations for the predicted physical quantities are expressed as follows: Where V is the two-dimensional measurement noise.

7. The control method of the wave adaptive ship propulsion control system according to claim 6, characterized in that: Specifically in step S4, the controller uses the deviation e(t) between the estimated state c(t) of the current operation depth and the desired optimal operation depth state r(t) as the input quantity for PID control: In the formula, , , are controller parameters, is the control output of the controller.

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