A closed-loop automatic control system and method for ship speed

Abstract

The present invention proposes a closed-loop automatic control system and method for ship speed. Feedback information is obtained by detecting a feedback module, and a final effective main engine speed command is generated through an outer-loop control module, so as to realize the conversion of outer-loop ship speed control into middle-loop main engine speed control. The main engine speed command is compared with the main engine speed n to obtain the speed deviation through the middle-loop control module, and a final effective main engine throttle command is generated, so as to realize the conversion of middle-loop main engine speed control into inner-loop throttle control. The throttle deviation between the main engine throttle command and the throttle feedback signal L is generated into an optimized throttle opening S through the inner-loop control module. The throttle closed-loop adjustment is completed, so as to realize the closed-loop automatic control of ship speed, so that the ship's navigation is gradually stable, the operation is safe, and the navigation efficiency is improved, so as to meet the requirements of stable, efficient, safe and reliable navigation of the ship.

Description

Technical Field

[0001] The present invention relates to ship speed optimization control in the shipping field, and in particular to a ship speed closed-loop automatic control system and method. Background Art

[0002] Ship speed is one of the key indicators of shipping economy, and it is of great concern to shipowners, cargo owners and charterers in ship operations. The ship speed is obtained by the main engine driving the propeller to push the ship to overcome the resistance of wind, waves and currents, and is achieved by controlling the main engine speed. According to the ship-engine-propeller matching theory, under calm conditions, there is a corresponding relationship between the ship speed and the propeller speed and the main engine speed. The ship's low-speed two-stroke main engine directly drives the propeller, and the main engine speed is the same as the propeller speed; the ship's medium-speed engine drives the propeller through a gearbox, and the medium-speed engine speed and the propeller speed have a ratio relationship; the ship's electric propulsion system controls the speed of the drive motor through the frequency converter to adjust the ship's speed. Therefore, controlling the main engine or propulsion motor speed indirectly adjusts the ship's speed.

[0003] However, the nonlinear correspondence between propeller speed and ship speed is affected by sea conditions. Simply controlling the diesel engine speed cannot ensure the stability of the ship's speed. This is because the current ship speed control is open-loop. The driver sets the propulsion main engine speed through the joystick. The main engine speed is limited by the control room and then changes the main engine fuel injection amount (throttle opening) to achieve closed-loop adjustment of the main engine speed and indirect control of the ship speed. There is a speed-speed correspondence table next to the joystick on the console to clarify it. However, due to the influence of wind, waves, hull dirt, etc., the ideal correspondence between the main engine speed and the ship speed changes. The speed generated by the propulsion ship at the same main engine speed will increase (such as downwind, downstream, etc.) or decrease (headwind, upstream, hull dirt, etc.). Since the ship speed does not have real-time feedback to form a closed-loop control, the speed is unstable. Therefore, it is not ideal to only control the main engine or propulsion motor speed and the propeller speed to stabilize the ship's navigation. The main goal of ship navigation is to pursue stable ship speed and safe operation of the main engine.

[0004] In particular, when the ship is against the wind and the current, and the hull is seriously dirty, it will cause problems such as main engine overload and black smoke, and the main engine performance will deteriorate under the influence of severe sea conditions. Many literatures on speed optimization are based on the ship propulsion mechanism to build an optimization principle model to calculate the main engine fuel consumption. Even if the ship speed optimization takes weather and sea conditions into consideration, its practicality and accuracy are very low. The fundamental reason is the open-loop control of the ship speed. The open-loop control of the ship speed leads to a deterioration in the accuracy of the ship speed. The driver and the ship control system have ignored the changes in resistance under the ship speed, and do not pay attention to the changes in the main engine speed corresponding to the ship speed and the causes of the abnormality. Summary of the invention

[0005] The purpose of the present invention is to solve the above-mentioned deficiencies and to propose a system or method that can realize closed-loop optimization control of ship speed, thereby ensuring stable and controllable navigation of the ship and safe operation of the main engine.

[0006] To achieve the above object, the present invention proposes a closed-loop automatic control system for ship speed, comprising the following modules:

[0007] Detection feedback module: used to detect and obtain feedback information and convert it into feedback signals;

[0008] Outer loop control module: used to convert the outer loop ship speed control into the middle loop main engine speed control by using the feedback signal;

[0009] Middle-loop control module: used to realize closed-loop control of the main engine speed, converting the middle-loop main engine speed control into inner-loop throttle control;

[0010] Inner loop control module: used to realize closed-loop adjustment of the main engine throttle, thereby realizing closed-loop automatic control of the ship's speed.

[0011] Furthermore, the feedback information includes the main engine shaft power , main engine speed n, actual ship speed And the main engine throttle injection amount L. Among them, the main engine shaft power is detected by the shaft power meter , the main engine speed n is detected by the magnetic pulse sensor at the flywheel, and the actual speed of the ship is obtained through the ship's voyage instrument or GPS The main engine fuel injection volume L of the electronic fuel injection type is obtained through the displacement of FIVA or the piston displacement sensor of the hydraulic high-pressure oil pump, and the main engine fuel injection volume L of the mechanical high-pressure oil pump is detected through the displacement sensor or the servo actuator motor encoder.

[0012] Furthermore, the feedback signal is an analog signal of 4-20 mA or 1-5 V. The feedback signal is also scaled to meet the signal requirements of the respective closed-loop comparison links.

[0013] Furthermore, the system is started through a function setting module, and the function setting module has a car clock and speed setting function, which is used to send a car order, and generate a 0-10V, 0-5V or ±5V electrical signal as a car order and a speed setting value through a potentiometer; through the function setting module, a ship speed control mode or a main engine speed control mode is selected; by selecting the ship speed control mode, the ship speed closed-loop automatic control system is started; in the ship speed control mode, the ship speed is set .

[0014] Furthermore, a function setting module is implemented using a composite handle on the bridge, the handle having 11 positions, including slow speed, slow speed, half speed, full speed and emergency reverse speed for reverse (AS), parking, slow speed, slow speed, half speed, full speed and full speed at sea for forward (AH);

[0015] The handle enters the host speed control mode through the function setting module, after the selection switches S1 and S2 are set to the left position EC, the host speed is set , at this time, the main engine speed is closed-loop controlled, and the ship speed is open-loop controlled;

[0016] The handle enters the ship speed control mode through the function setting module, and after the selection switches S1 and S2 are set to the right position BC, the ship speed is set. , at this time the speed is closed-loop controlled.

[0017] Furthermore, the outer loop control module includes:

[0018] Ship power demand submodule: Based on the ship power-speed algorithm, it is used to set the speed The actual speed Compared with the speed deviation obtained Generate the main engine power variable through the ship resistance model , and then calculate the required main engine power of the ship ;

[0019] The calculation formula 1 of the speed deviation is: ;

[0020] The ship resistance model calculation formula 2 is: ,in, is the ship resistance coefficient, which is affected by sea conditions and ship conditions. size;

[0021] The main engine power required for the ship The calculation formula 3 is: , where is the propulsion power required by the ship at the corresponding speed, that is, the main engine shaft power obtained by the shaft power meter in the above feedback signal; , The power adjusted each time is used to prevent excessive single power adjustment from causing power step changes and affecting the stability of the host.

[0022] Main engine speed generation submodule: Based on the main engine speed-power algorithm, it is used to convert the main engine power required by the ship The required main engine speed of the ship is obtained through the ship propulsion formula ; The ship propulsion formula 4 is: ,

[0023] in, is the torque coefficient; at the same time, - It must be within the allowable range of the ship's propulsion characteristics, that is, it must meet the ship-main engine matching design curve.

[0024] Main engine speed setting submodule: Use the main engine speed required by the ship , through the host speed command control, generate the host speed command , automatically adapt to the ship speed and realize ship speed control;

[0025] The host speed command limiting submodule is used to limit the host speed command After passing the speed limit, the final effective host speed command is generated In the main engine speed command limiting submodule, the main engine speed command output by the ship speed control , it needs to go through the main engine speed limit link, including the minimum stable speed limit, critical speed limit, control room (chief engineer) limit, acceleration rate limit, program load limit, and maximum speed limit. Compared to these speed limits, if When these limits are exceeded, It does not work. The speed command selects the speed limit value. After the speed limit, the host speed command generated is .

[0026] Furthermore, in the main engine speed setting submodule, the ship speed control implemented is divided into progressive tracking control (changing the ship speed set value) and speed control (vessel speed Constant value):

[0027] A) The progressive tracking control method is: when the ship speed is in the follow-up or acceleration / deceleration program control, due to the large inertia of the ship, in order to prevent the main engine from suddenly increasing or decreasing the load, the main engine speed command Through the adjustable step length δT and step height δn, the main engine speed set value is gradually tracked to So that the actual ship speed Can gradually track to the set speed ; Among them, the progressive tracking formula 5 is: , where δn is the absolute value speed regulation, “+” indicates speed increase regulation, and “-” indicates speed decrease regulation; , m To adjust the number of times, i =0,1,… m; T is the total adjustment time, δT is the variable interval time of each adjustment, δT depends on the ship inertia, the larger the ship inertia, the larger δT, and the smaller the ship inertia, the smaller δT, so that the actual speed approaches the given speed in the form of a soaring curve, so that the actual ship speed Can gradually track the set speed .

[0028] B) The method of speed maintenance control is: when the speed is maintained When the fixed value is controlled, the actual ship speed Deviation from set speed The deviation between hour, It is a configurable speed dead zone. When the speed is in the dead zone, the ship speed controller does not work. The dead zone value can be set according to the sea conditions, such as calm sea =0.1 knots, in severe sea conditions =2knots, etc.; if Beyond the dead zone of ship speed, When the host generates a new speed setting ,Right now ,function It includes the ship power-speed algorithm and the main engine speed-power algorithm, namely:

[0029] ,

[0030] In the formula η For the host propulsion system efficiency, ρ is the density of seawater, is the propeller diameter, is the torque coefficient, is the propulsion power required by the ship at the corresponding speed, that is, the main engine shaft power obtained by the shaft power meter in the above feedback signal.

[0031] Furthermore, the central control module includes a main engine speed closed-loop control submodule and a main engine load limiting submodule:

[0032] The host speed control submodule is used to convert the host speed instruction Speed ​​deviation compared to the main engine speed n Through the host speed controller, the throttle injection amount setting value is converted ;

[0033] Speed ​​deviation The calculation formula 6 is: ;

[0034] The host load limiting submodule is used to set the throttle fuel injection amount to a certain value. After load limiting processing, the final effective host throttle command is generated Load restrictions include minimum fuel supply limit, starting fuel supply setting, boost air pressure limit, torque limit and maximum fuel supply limit. Compared with these load limits, if Exceeding the load limit, It does not work. The throttle command selects the load limit value. After the load limit is passed, the effective throttle command is finally generated as .

[0035] Furthermore, the main engine speed controller adopts PID algorithm as the main method and machine learning algorithm as the auxiliary method; learning ship speed The machine learning algorithm is effective only after the PID is applied to compensate for the PID speed regulation algorithm. The PID control parameter has a proportional coefficient K. p , integral coefficient K i , differential coefficient K d These parameters need to be set by manual experience and optimized online; the machine learning algorithm is a speed machine learning algorithm, such as fuzzy neural network, genetic algorithm, evolutionary algorithm, particle swarm algorithm, support vector machine, etc. The machine learning algorithm is used to fine-tune PID control parameters or superimpose on the PID output for compensation to prevent the main engine speed from overshooting, oscillation or untimely control.

[0036] Furthermore, the inner loop control module includes:

[0037] Throttle limit submodule: used to convert the host throttle command The throttle deviation is compared with the throttle feedback signal L , after the throttle dead zone limit processing, the generated ;

[0038] Throttle scale calibration submodule: generate After the throttle-speed calibration process, the throttle command after the throttle scale calibration is generated ;

[0039] The throttle-speed calibration processing method is: After the throttle scale signal (vertical axis) and the host speed signal (horizontal axis) provided by the host manufacturer are calibrated, the throttle position adjustment accuracy is improved. The throttle (fuel injection amount) command after the throttle scale calibration is .

[0040] Throttle scale adjustment submodule: used to adjust the throttle command The throttle controller generates the throttle opening S; wherein the throttle command The throttle actuator is divided into servo motor type throttle position control and FIVA or ELFI type hydraulic injection quantity control. The former has its own angle encoder to complete the throttle position closed-loop adjustment, and the latter uses a displacement sensor to detect the injection plunger stroke to complete the injection quantity closed-loop adjustment.

[0041] Furthermore, due to the large difference in the quality of the fuel burned by the main engine, the power emitted by the main engine after the same amount of fuel is burned is different, which will cause the control system to misjudge whether the control effect is weak or strong and further increase or decrease the amount of fuel injection; on the other hand, severe sea conditions, headwind and upstream, dirty hull, etc. will increase the resistance of the ship and make the ship speed-propulsion power matching abnormal. Therefore, the throttle controller is also provided with a throttle optimization control submodule, which converts the actual speed of the ship into the power (vertical coordinate) matching curve based on the ship speed (horizontal coordinate)-power (vertical coordinate) matching curve. - Actual propulsion shaft power The matching curve is compared and analyzed with the ideal speed-power matching curve, and the throttle optimization control is performed through the throttle actuator to achieve throttle closed-loop adjustment.

[0042] The throttle controller mainly adopts PI control algorithm and uses throttle optimization control submodule to optimize the proportional coefficient and integral coefficient of throttle control intensity, achieve the best match between ship and engine, prevent frequent changes, throttle overshoot, unstable main engine load, and adapt to changes in sea conditions and ship conditions, such as headwind and current or dirty hull, etc. - If the curve becomes steeper, the control coefficient of the throttle controller PI will become weaker to prevent the host from overloading.

[0043] Furthermore, the throttle optimization control method is:

[0044] The actual speed -power The matching curve is compared with the ideal speed-power matching curve as follows:

[0045] 1) If - The matching curve becomes steeper than the ideal speed-power matching curve, that is, more propulsion power is required at the same speed, and the main engine throttle becomes larger, indicating that the ship resistance has increased. At this time, the control system cannot further increase the throttle to meet the set speed. It is allowed that the actual speed does not reach the given speed to prevent the main engine from overloading and the ship's energy efficiency from deteriorating;

[0046] 2) If - The matching curve is below the ideal speed-power matching curve, that is, less propulsion power is required at the same speed, and the main engine throttle becomes smaller, indicating that the ship is sailing with the wind and the current and the resistance is reduced. At this time, the control system will further reduce the throttle until the actual speed is maintained within the given speed range, thereby saving fuel for the main engine and improving the energy efficiency of the ship.

[0047] 3) - The matching curve is the best match, which directly optimizes the throttle scale or throttle position adjustment link to prevent ship speed control oscillation and throttle saturation.

[0048] Furthermore, the throttle scale signal is 1-5V or 4-20mA.

[0049] Furthermore, in the throttle limiting submodule, the throttle dead zone limiting processing method is:

[0050] The throttle deviation calculation formula 7 is: ;

[0051] Will With adjustable throttle deadband In comparison, The dead zone value can be set according to the sea conditions. In calm sea conditions, is the minimum value, in severe sea conditions Take the maximum value to prevent frequent throttle movements;

[0052] when hour, When in the dead zone, the throttle controller output remains unchanged and the throttle actuator does not act;

[0053] when When the throttle controller output starts to change, the throttle adjustment mechanism starts to operate.

[0054] The present invention also proposes a closed-loop automatic control method for ship speed, which is based on the above-mentioned closed-loop automatic control system for ship speed and includes the following steps:

[0055] S1: Obtain feedback information by detecting the feedback module, and the feedback information includes the main engine shaft power , main engine speed n, ship speed and the main engine throttle injection amount L;

[0056] S2: Set the speed Actual speed Speed ​​deviation Generate the final effective host speed command through the outer loop control module , realizing the conversion of outer loop ship speed control into middle loop main engine speed control;

[0057] S3: Set the host speed command The speed deviation obtained by comparing with the main engine speed n Generate the final effective host throttle command through the central control module , realizing the conversion of middle ring host speed control to inner ring throttle control;

[0058] S4: Set the host throttle command The throttle deviation is compared with the throttle feedback signal L , through the inner loop control module, the optimized throttle opening S is generated to achieve throttle closed-loop adjustment.

[0059] Furthermore, step S2 is specifically as follows:

[0060] 2.1: Obtain the ship's set speed through formula 1 Actual speed Speed ​​deviation ;

[0061] 2.2: Through the ship power demand submodule, the speed deviation According to formula 2, the host power variable is generated , and then according to formula 3, the required main engine power of the ship is obtained ;

[0062] 2.3: Generate the required main engine power of the ship through the main engine speed generation submodule By using formula 4, we can get the required main engine speed of the ship. ;

[0063] 2.4: Set the required main engine speed of the ship Input to the host speed setting submodule to generate the host speed command ;

[0064] 2.5: Set the host speed command Enter the host speed command limit submodule, and the host speed command generated after the speed limit is obtained is .

[0065] Furthermore, step S3 is specifically as follows:

[0066] 3.1: Through formula 6, get the host speed command Speed ​​deviation from the main engine speed n ;

[0067] 3.2: After inputting into the host speed controller, the host throttle command is obtained ;

[0068] 3.3: Set the host throttle command Input the host load limit submodule, and after load limit processing, generate the final effective host throttle command .

[0069] Furthermore, step S4 is specifically as follows:

[0070] 4.1: Using formula 7, get the effective host throttle command Throttle deviation from throttle injection amount L ;

[0071] 4.2: Adjust the throttle deviation Input throttle limit submodule, generated after throttle dead zone limit processing ;

[0072] 4.3: Generate Through the throttle scale calibration submodule, after the throttle-speed calibration process, the throttle command after throttle scale calibration is generated ;

[0073] 4.4: The throttle command after throttle scale calibration The throttle scale adjustment submodule is input, and the throttle displacement / fuel injection amount, i.e., the throttle opening S, is generated through the throttle controller; the throttle opening S is transmitted to the throttle actuator for throttle adjustment, thereby changing the amount of fuel injected into the cylinder per cycle of the main engine.

[0074] The premise of closed-loop control of ship speed is to ensure that the main engine is safe, stable and not overloaded. Therefore, the closed-loop regulation of ship speed in the present invention is differential regulation. The deviation between the actual speed value and the speed setting value is Only under ideal sea and ship conditions can =0, in severe sea conditions, headwind and current, dirty hull, etc. ≠0, the final result of the closed-loop speed regulation is that the main engine is not overloaded and is stable, and the actual speed Gradually stabilize at the set speed value Nearby, without showing actual speed Around set speed Oscillation situation.

[0075] Compared with the prior art, the advantages of the present invention are:

[0076] 1. The present invention forms a closed-loop speed control system through a detection feedback module, an outer-loop control module, a middle-loop control module and an inner-loop control module. The outer-loop ship speed control is converted into the middle-loop main engine speed control by using the submodules and algorithms in the outer-loop control module; the main engine speed controller and the main engine load limiting submodule in the middle-loop control module are used to control the main engine speed and convert the middle-loop main engine speed control into the inner-loop throttle control. Finally, the inner-loop throttle control module is used to optimize the throttle control to realize the closed-loop automatic control of the ship speed, so that the ship's navigation is gradually stable, the operation is safe, and the navigation efficiency is improved, thereby meeting the requirements of stable, efficient, safe and reliable navigation of the ship.

[0077] 2. The closed-loop regulation of ship speed of the present invention is a differential regulation. Taking into account the adverse sea conditions, abnormal ship conditions, abnormal propulsion system and other situations, the actual speed is gradually stabilized near the set speed value through differential regulation to avoid the actual speed oscillating around the set speed, ensure the stability of the main engine and prevent the main engine from being overloaded.

[0078] 3. The present invention sets a throttle optimization control submodule, optimizes the proportional coefficient and integral coefficient of the throttle control intensity based on the matching characteristics of the actual speed of the ship and the actual propulsion shaft power, and achieves the best ship-engine matching, thereby adapting to changes in sea conditions or ship conditions, preventing frequent changes, throttle overshoot or unstable main engine load, and improving the energy efficiency of the ship.

[0079] 4. The present invention adopts PID algorithm and machine learning algorithm in the host speed controller to obtain the throttle setting value through PID calculation of the speed deviation, wherein the PID algorithm is mainly used, and the machine learning algorithm is effective for compensation only after the PID algorithm takes effect. Through the machine learning algorithm, the PID control parameters are fine-tuned or superimposed on the PID output, which plays an auxiliary role in compensation, optimizes the host speed regulation process, prevents the host speed from overshooting, oscillation or untimely control, and ensures the stability of the host speed. BRIEF DESCRIPTION OF THE DRAWINGS

[0080] Figure 1 This is a schematic diagram of the structure of a closed-loop automatic control system for ship speed according to an embodiment of the present invention;

[0081] Figure 2 The figure is a flow chart of a closed-loop automatic control method for ship speed according to an embodiment of the present invention. DETAILED DESCRIPTION

[0082] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be further described below.

[0083] This embodiment proposes a closed-loop automatic control system for ship speed, such as Figure 1As shown, the system consists of a function setting module, a detection feedback module, an outer loop control module, a middle loop control module and an inner loop control module.

[0084] Among them, the function setting module has the functions of car clock and speed setting, which is used to send car orders, and generate 0-10V, 0-5V or ±5V electrical signals as car orders and speed setting values ​​through the potentiometer. The function setting module selects the ship speed control mode or the main engine speed control mode through the composite handle of the bridge. In this embodiment, the composite handle of the bridge has 11 positions, including the micro speed, slow speed, half speed, full speed and emergency reversing speed of reverse (AS), parking, micro speed, slow speed, half speed, full speed and full speed at sea of ​​forward (AH); when the handle selection switches S1 and S2 are set to the left position EC, the main engine speed control mode is entered, and the main engine speed is set. At this time, the main engine speed is closed-loop controlled, and the ship speed is open-loop controlled; when the handle is set to the right position BC through the selection switches S1 and S2, the ship speed control mode is entered, and the ship speed is set. , at this time the speed is closed-loop controlled.

[0085] The detection feedback module is used to detect and obtain feedback information and convert it into a feedback signal. The feedback signal must also be scaled to meet the signal requirements of each closed-loop comparison link. In this embodiment, the feedback signal is a 4-20mA or 1-5V analog signal. The feedback information includes the main engine shaft power , main engine speed n, ship speed And the main engine throttle injection amount L. Among them, the main engine shaft power is detected by the shaft power meter The magnetic pulse sensor at the flywheel detects the main engine speed n, and the ship speed is obtained through the ship's voyage meter or GPS The main engine fuel injection volume L of the electronic fuel injection type is obtained through the displacement of FIVA or the piston displacement sensor of the hydraulic high-pressure oil pump, and the main engine fuel injection volume L of the mechanical high-pressure oil pump is detected through the displacement sensor or the servo actuator motor encoder.

[0086] The outer loop control module receives the feedback signal from the detection feedback module, and converts the outer loop ship speed control into the middle loop main engine speed control through its internal submodules to obtain the main engine speed command. ; The outer loop control module specifically includes the following submodules:

[0087] (a) Ship power demand submodule: Based on the ship power-speed algorithm, it is used to set the speed The actual speed Compared with the speed deviation obtained Generate the main engine power variable through the ship resistance model , and then calculate the required main engine power of the ship ;

[0088] The calculation formula of speed deviation is: ;

[0089] The calculation formula 2 of the ship resistance model is: ,in, is the ship resistance coefficient, which is affected by sea conditions and ship conditions. size;

[0090] Main engine power required by the ship The calculation formula 3 is: ,in, is the propulsion power required by the ship at the corresponding speed, that is, the main engine shaft power obtained by the shaft power meter in the above feedback signal; , The power adjusted each time can prevent a single power adjustment from being too large, causing a power step change and affecting the stability of the host.

[0091] (b) Main engine speed generation submodule: Based on the main engine speed-power algorithm, it is used to convert the main engine power required by the ship into The required main engine speed of the ship is obtained through the ship propulsion formula ;Ship propulsion formula 4 is: ,

[0092] in, is the torque coefficient; at the same time, - It must be within the allowable range of the ship's propulsion characteristics, that is, it must meet the ship-main engine matching design curve.

[0093] (c) Main engine speed setting submodule: Use the main engine speed required by the ship , through the host speed command control, generate the host speed command , automatically adapt to the ship speed and realize ship speed control;

[0094] The methods of achieving ship speed control are divided into progressive tracking control (changing ship speed set value) and speed control (vessel speed Constant value):

[0095] The progressive tracking control method is: when the ship speed is in the follow-up or acceleration / deceleration program control, due to the large inertia of the ship, in order to prevent the main engine from suddenly increasing or decreasing the load, the main engine speed command Through the adjustable step length δT and step height δn, the main engine speed set value is gradually tracked to So that the actual ship speed Can gradually track to the set speed ; Among them, the progressive tracking formula 5 is: , where δn is the absolute value speed regulation, “+” indicates speed increase regulation, and “-” indicates speed decrease regulation; , m To adjust the number of times, i =0,1,… m ; T is the total adjustment time, δT is the variable interval time of each adjustment, δT depends on the ship inertia, the larger the ship inertia, the larger δT, and the smaller the ship inertia, the smaller δT, so that the actual speed approaches the given speed in the form of a soaring curve, so that the ship speed Can gradually track the set speed .

[0096] The method of speed maintenance control is: when the speed is maintained When the fixed value is controlled, the actual ship speed Deviation from the set speed The deviation between hour, It is a configurable speed dead zone. When the speed is in the dead zone, the ship speed controller does not work. The dead zone value can be set according to the sea conditions, such as calm sea =0.1 knots, in severe sea conditions =2knots, etc.; if Beyond the dead zone of ship speed, When the host generates a new speed setting ,Right now ,function It includes the ship power-speed algorithm and the main engine speed-power algorithm, namely: , where η For the host propulsion system efficiency, ρ is the density of seawater, is the propeller diameter, is the torque coefficient, It is the propulsion power required for the ship at the corresponding speed.

[0097] (d) Host speed command limiting submodule: used to limit the host speed command After passing the speed limit, the final effective host speed command is generated In the main engine speed command limiting submodule, the main engine speed command output by the ship speed control , it needs to go through the main engine speed limit link, including the minimum stable speed limit, critical speed limit, control room (chief engineer) limit, acceleration rate limit, program load limit, and maximum speed limit. Compared to these speed limits, if When these limits are exceeded, It does not work. The speed command selects the speed limit value. After the speed limit, the host speed command generated is .

[0098] In this embodiment, the middle ring control module is used to realize the closed-loop control of the main engine speed, and convert the middle ring main engine speed control into the inner ring throttle control; the middle ring control module is composed of the main engine speed closed-loop control submodule and the main engine load limit submodule, wherein the main engine speed control submodule is used to convert the main engine speed instruction Speed ​​deviation compared to the main engine speed n Through the host speed controller, the throttle injection amount setting value is converted ;Speed ​​deviation The calculation formula 6 is: ; The main engine speed controller is based on PID control algorithm, supplemented by machine learning algorithm; the ship speed and its rate of change and its rate of change At the same time, after inputting into the speed learning module, the ship speed is learned The PID speed control algorithm and its change compensation are input into the speed learning module to learn the ship speed. The machine learning algorithm is effective only after the PID is applied to compensate for the PID speed control algorithm. In the PID control algorithm, the PID control parameters have a proportional coefficient K. p , integral coefficient K i , differential coefficient K d These parameters need to be set by manual experience and optimized online; the machine learning algorithm is a speed machine learning algorithm, such as fuzzy neural network, genetic algorithm, evolutionary algorithm, particle swarm algorithm, support vector machine, etc. The machine learning algorithm is used to fine-tune the PID control parameters or superimpose on the PID output for compensation to prevent the main engine speed from overshooting, oscillation or untimely control.

[0099] In addition, the host load limit submodule is used to set the throttle injection amount obtained by the host speed control submodule. After load limiting processing, the final effective host throttle command is generated The load limit includes the minimum fuel supply limit, starting fuel supply setting, boost air pressure limit, torque limit and maximum fuel supply limit. Compared with these load limits, if Exceeding the load limit, It does not work. The throttle command selects the load limit value. After the load limit is passed, the effective throttle command is finally generated as .

[0100] The inner loop control module is used to realize the closed-loop adjustment of the main engine throttle, thereby realizing the closed-loop automatic control of the ship's speed; the inner loop control module is specifically composed of the following sub-modules:

[0101] (a) Throttle limit submodule: used to convert the host throttle command obtained by the host load limit submodule into Compared with the throttle feedback signal L, the throttle deviation is obtained , and then adjust the throttle deviation After the throttle dead zone limit processing, the generated ; Among them, the throttle deviation calculation formula 7 is: ; The throttle dead zone limitation processing method is: With adjustable throttle deadband In comparison, The dead zone value can be set according to the sea conditions. In calm sea conditions, is the minimum value, in severe sea conditions Take the maximum value to prevent frequent throttle action; when hour, When in the dead zone, the throttle controller output remains unchanged and the throttle actuator does not act; When the throttle controller output starts to change, the throttle adjustment mechanism starts to operate.

[0102] (b) Throttle scale calibration submodule: The throttle scale calibration submodule generates the After the throttle-speed calibration process, the throttle command after the throttle scale calibration is generated Specifically, the 1-5V or 4-20mA throttle scale signal and the host speed signal are calibrated to improve the throttle position adjustment accuracy. The throttle after throttle scale calibration, that is, the injection quantity instruction is recorded as .

[0103] (c) The throttle-speed calibration process is: After the throttle scale signal (ordinate) and the host speed signal (abscissa) provided by the host manufacturer are calibrated, the throttle position adjustment accuracy is improved. The throttle (fuel injection amount) command after the throttle scale calibration is .

[0104] (d) The throttle scale adjustment submodule is used to convert the above throttle command The throttle controller generates the throttle opening S; wherein the throttle command The throttle actuator is divided into servo motor type throttle position control and FIVA or ELFI type hydraulic injection quantity control. The former has its own angle encoder to complete the throttle position closed-loop adjustment, and the latter uses a displacement sensor to detect the injection plunger stroke to complete the injection quantity closed-loop adjustment.

[0105] Due to the large difference in the quality of the fuel burned by the main engine, the power emitted by the main engine after the same amount of fuel is burned is different, which will cause the control system to misjudge whether the control effect is weak or strong and further increase or reduce the amount of fuel injection; on the other hand, severe sea conditions, headwind and upstream, dirty hull, etc. will increase the resistance of the ship and make the ship speed-propulsion power matching abnormal. Therefore, the above-mentioned throttle controller is also provided with a throttle optimization control submodule:

[0106] The throttle optimization control submodule converts the actual speed of the ship into - Actual propulsion shaft power -Compare and analyze the matching curve with the ideal speed-power matching curve, optimize the throttle control through the throttle actuator, and realize the throttle closed-loop adjustment.

[0107] In this embodiment, the throttle controller mainly adopts the PI control algorithm, and uses the throttle optimization control submodule to optimize the proportional coefficient and integral coefficient of the throttle control intensity to achieve the best match between the ship and the engine, prevent frequent changes, throttle overshoot, and unstable main engine load, and adapt to changes in sea conditions and ship conditions, such as headwind and current or dirty hull, etc. - The steeper the curve, the weaker the control coefficient of the throttle controller PI is, to prevent the host from overloading. The specific method of optimizing the throttle control through the throttle controller is as follows:

[0108] The actual speed -power The matching curve is compared with the ideal speed-power matching curve as follows:

[0109] 1) If - The matching curve becomes steeper than the ideal speed-power matching curve, that is, more propulsion power is required at the same speed, and the main engine throttle becomes larger, indicating that the ship resistance has increased. At this time, the control system cannot further increase the throttle to meet the set speed. It is allowed that the actual speed does not reach the given speed to prevent the main engine from overloading and the ship's energy efficiency from deteriorating;

[0110] 2) If - The matching curve is below the ideal speed-power matching curve, that is, less propulsion power is required at the same speed, and the main engine throttle becomes smaller, indicating that the ship is sailing with the wind and the current and the resistance is reduced. At this time, the control system will further reduce the throttle until the actual speed is maintained within the given speed range, thereby saving fuel for the main engine and improving the energy efficiency of the ship.

[0111] 3) - The matching curve is the best match, which directly optimizes the throttle scale or throttle position adjustment link to prevent ship speed control oscillation and throttle saturation.

[0112] The method flow of realizing closed-loop automatic control of ship speed through the closed-loop automatic control system of ship speed proposed in the above embodiment is as follows: Figure 2 As shown, the specific steps include:

[0113] S1: Obtain feedback information by detecting the feedback module, and the feedback information includes the main engine shaft power , main engine speed n, ship speed And the host throttle injection amount L.

[0114] S2: Set the speed The actual speed Compared with the speed deviation obtained Generate the final effective host speed command through the outer loop control module , realizing the conversion of outer loop ship speed control into middle loop main engine speed control;

[0115] 2.1: Obtain the ship's set speed through formula 1 The actual speed Speed ​​deviation ;

[0116] 2.2: Through the ship power demand submodule, the speed deviation According to formula 2, the host power variable is generated , and then according to formula 3, the required main engine power of the ship is obtained ;

[0117] 2.3: Generate the required main engine power of the ship through the main engine speed generation submodule By using formula 4, we can get the required main engine speed of the ship. ;

[0118] 2.4: Set the required main engine speed of the ship Input to the host speed setting submodule to generate the host speed command ;

[0119] 2.5: Set the host speed command Input the host speed command limit submodule, and the host speed command generated after the speed limit is obtained is .

[0120] S3: Set the host speed command Speed ​​deviation compared to the main engine speed n Generate the final effective host throttle command through the central control module , realizing the conversion of middle ring host speed control to inner ring throttle control;

[0121] 3.1: Through formula 6, get the host speed command Speed ​​deviation from the main engine speed n ;

[0122] 3.2: After inputting into the host speed controller, the host throttle command is obtained ;

[0123] 3.3: Set the host throttle command Input the host load limit submodule, and after load limit processing, generate the final effective host throttle command .

[0124] S4: Set the host throttle command The throttle deviation is compared with the throttle feedback signal L , through the inner loop control module, the optimized throttle opening S is generated to achieve throttle closed-loop adjustment.

[0125] 4.1: Using formula 7, get the effective host throttle command Throttle deviation from throttle injection amount L ;

[0126] 4.2: Adjust the throttle deviation Input throttle limit submodule, generated after throttle dead zone limit processing ;

[0127] 4.3: Generate Through the throttle scale calibration submodule, after the throttle-speed calibration process, the throttle command after throttle scale calibration is generated ;

[0128] 4.4: The throttle command after throttle scale calibration The throttle scale adjustment submodule is input, and the throttle displacement / fuel injection amount, i.e., the throttle opening S, is generated through the throttle controller; the throttle opening S is transmitted to the throttle actuator for throttle adjustment, thereby changing the amount of fuel injected into the cylinder per cycle of the main engine.

[0129] The above is only a preferred embodiment of the present invention and does not limit the present invention in any way. Any technician in the relevant technical field, without departing from the scope of the technical solution of the present invention, makes any form of equivalent replacement or modification to the technical solution and technical content disclosed in the present invention, which does not depart from the content of the technical solution of the present invention and still falls within the protection scope of the present invention.

Claims

1. A closed-loop automatic control system for ship speed, characterized in that: include: Detection feedback module: used to detect and obtain feedback information and convert it into feedback signals; Outer loop control module: used to convert the outer loop ship speed control into the middle loop main engine speed control by using the feedback signal; The outer loop control module comprises: Ship power demand submodule: Based on the ship power-speed algorithm, it is used to set the speed V s * The actual speed V s Speed ​​deviation ΔV s After the ship resistance model, the main engine power variable ΔP is generated * , and then through calculation, we can get the main engine power P required by the ship E * ; Main engine speed generation submodule: Based on the main engine speed-power algorithm, it is used to convert the main engine power P required by the ship E * Through the ship propulsion formula, the required main engine speed n of the ship is obtained s * ; Main engine speed setting submodule: Use the main engine speed n required by the ship s * , through the host speed command control, generate the host speed command n * , to achieve ship speed control; The host speed command limiting submodule is used to limit the host speed command n * After passing the speed limit, the final effective host speed command n is generated E * ; Middle loop control module: used to realize the closed loop control of the main engine speed and generate the final effective main engine throttle command L S * , converting the middle ring host speed control into inner ring throttle control; The central control module includes a main engine speed closed-loop control submodule and a main engine load limiting submodule: The host speed closed-loop control submodule is used to convert the host speed instruction n E * The speed deviation Δn compared with the main engine speed n is converted into the throttle injection amount setting value L through the main engine speed controller E * ; The host load limiting submodule is used to set the throttle fuel injection amount to a value L E * After load limiting processing, the final effective host throttle command L is generated. S * ; Inner loop control module: used to realize closed-loop adjustment of the main engine throttle, thereby realizing closed-loop automatic control of the ship's speed; The inner loop control module comprises: Throttle limit submodule: used to convert the host throttle command L S * The throttle deviation ΔL is compared with the throttle feedback signal L, and after the throttle dead zone limitation processing, ΔL is generated. S ; Throttle scale calibration submodule: The generated ΔL S After the throttle-speed calibration process, the throttle command S after throttle scale calibration is generated. * ; Throttle scale adjustment submodule: used to adjust the throttle command S * The throttle opening S is generated through the throttle controller; The throttle controller is also provided with a throttle optimization control submodule, which converts the actual speed V of the ship into s - Actual propulsion shaft power P s The matching curve is compared and analyzed with the ideal speed-power matching curve, and the throttle optimization control is performed through the throttle actuator to achieve throttle closed-loop adjustment.

2. The closed-loop automatic control system for ship speed according to claim 1 is characterized in that: The feedback information includes the main engine shaft power P s , main engine speed n, actual ship speed V s And the host throttle injection amount L.

3. The closed-loop automatic control system for ship speed according to claim 2 is characterized in that: The system is started by a function setting module, which is used to send a vehicle command and select a ship speed control mode or a host control mode; by selecting the ship speed control mode, the ship speed closed-loop automatic control system is started; in the ship speed control mode, the ship speed V is set. s * .

4. The closed-loop automatic control system for ship speed according to claim 1 is characterized in that: In the main engine speed setting submodule, the ship speed control implemented is divided into progressive tracking control and speed keeping control: The method of progressive tracking control is: when the ship speed is in the following or acceleration and deceleration program control, the main engine speed command n * Through the adjustable step length δT and step height δn, the main engine speed set value is gradually tracked to n s * So the actual speed of the ship V s Can gradually track the set speed V s * ; The method of speed control is: when the speed is maintained at V s * When the fixed value is controlled, the actual speed V s Deviation from given ship speed |ΔV s ∣≤V DB When V DB is the configurable speed dead zone, ΔV s When the ship speed is in the dead zone, the ship speed controller does not work, V DB The dead zone value can be set according to the sea conditions; if ΔV s Exceeding the dead zone of ship speed, i.e. |ΔV s ∣>V DB When the new host speed setting n is generated s * , that is, n s * =f(ΔV s ), function f(ΔV s ) includes the ship power-speed algorithm and the main engine speed-power algorithm.

5. The closed-loop automatic control system for ship speed according to claim 1 is characterized in that: The host speed controller adopts PID algorithm as the main method and machine learning algorithm as the auxiliary method; the machine learning algorithm is used to fine-tune PID control parameters or compensate on PID output.

6. The closed-loop automatic control system for ship speed according to claim 1 is characterized in that: In the throttle limiting submodule, the throttle dead zone limiting processing method is: The |ΔL| and the configurable throttle dead zone L DB In comparison, L DB The dead zone value can be set according to the sea conditions. In calm sea conditions, L DB is the minimum value. In severe sea conditions, L DB Take the maximum value to prevent frequent throttle movements; When |ΔL|≤L DB When ΔL is within the dead zone, the throttle controller output remains unchanged and the throttle actuator does not act; When |ΔL|>L DB When the throttle controller output starts to change, the throttle adjustment mechanism starts to operate.

7. A closed-loop automatic control method for ship speed, based on the closed-loop automatic control system for ship speed according to any one of claims 1 to 6, characterized in that: The steps include: S1: Obtain feedback information by detecting the feedback module, and the feedback information includes the main engine shaft power P s , main engine speed n, actual ship speed V s and the main engine throttle injection amount L; S2: Set the speed V s * The actual speed V s Speed ​​deviation ΔV s Through the outer loop control module, the final effective host speed command n is generated E * , realizing the conversion of outer loop ship speed control into middle loop main engine speed control; S3: Set the host speed command n E * The speed deviation Δn compared with the main engine speed n is generated through the middle loop control module to generate the final effective main engine throttle command L S * , realizing the conversion of middle ring host speed control to inner ring throttle control; S4: Set the host throttle command L S * The throttle deviation ΔL obtained by comparing with the throttle feedback signal L is used to generate the optimized throttle opening S through the inner loop control module to achieve throttle closed-loop regulation.

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