An electric ship energy optimization method, device, equipment and medium

Abstract

The present application relates to the field of ship navigation technology, in particular to an electric ship energy optimization method, device, equipment and medium. The present application first constructs a speed constraint based on the distance of the voyage and the set total navigation time, then deduces the joint constraint of battery power and generator power based on the speed constraint. At the same time, based on the battery state of charge evolution law and the rated capacity limit, a refined battery attenuation constraint is established. Finally, under the conditions of joint constraint, speed constraint and battery power constraint, the total loss function of the ship is optimized to optimize the speed, generator start-stop state and battery power and generator power. The present application can effectively reduce the battery cycle depth and life loss and improve the economy of operation under the premise of guaranteeing the task navigation time requirement.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of ship navigation technology, in particular to an electric ship energy optimization method, device, equipment and medium. BACKGROUND

[0002] All-electric ships gradually get applied in inland shipping and offshore transportation scenarios due to their zero emissions and low noise advantages. In order to extend the voyage and improve the operation efficiency, the current ships are equipped with hybrid electric propulsion systems composed of energy storage battery systems and auxiliary generators. At the same time, the energy scheduling and voyage management of the ship increasingly rely on intelligent optimization methods to improve the overall energy efficiency and system reliability.

[0003] The prior art optimizes the route and sailing speed to ensure that the ship completes the navigation task within the specified navigation time, but the sailing speed is related to the generator power and the battery power. The prior art does not consider the battery power loss of the battery while optimizing the sailing speed in order to complete the navigation task, thereby making it difficult to balance the battery loss while optimizing the sailing speed.

[0004] In summary, the prior art reduces the ship navigation efficiency due to not considering the battery loss.

[0005] Therefore, the prior art still needs to be improved and improved. SUMMARY

[0006] To solve the above technical problems, the present application provides an electric ship energy optimization method, device, equipment and medium, which solves the problem that the prior art reduces the ship navigation efficiency due to not considering the battery loss.

[0007] To achieve the above purpose, the present application adopts the following technical solutions:

[0008] In a first aspect, the present application provides an electric ship energy optimization method, which comprises:

[0009] Obtain the voyage distance of the ship to be navigated, obtain the total navigation time set for the ship to navigate in advance, and based on the voyage distance and the total navigation time, construct the speed constraint of the ship;

[0010] Based on the speed constraint, construct the propulsion power constraint of the ship, and based on the propulsion power constraint, construct the battery-generator combined power constraint;

[0011] Obtain the rated capacity of the battery, and based on the rated capacity of the battery, construct the battery power constraint;

[0012] obtaining a total loss function constructed based on a battery power and a generator power of the ship and a generator start-stop state related to the generator power, and optimizing the sailing speed, the generator start-stop state, the battery power and the generator power based on the battery-generator combined power constraint and the sailing speed constraint and the battery power constraint, with the total loss function as an optimization target.

[0013] In an implementation manner, the battery-generator combined power constraint is constructed based on the propulsion power constraint, including:

[0014] obtaining a power of an electrical equipment powered by the ship;

[0015] obtaining a power provided by the ship according to a sum of the battery power and the generator power of the ship;

[0016] determining a constraint of the power provided by the ship based on the power of the electrical equipment and the propulsion power constraint, and taking the constraint of the power provided by the ship as the battery-generator combined power constraint.

[0017] In an implementation manner, the battery power constraint is constructed based on the battery rated capacity, including:

[0018] obtaining a set battery energy storage value constraint;

[0019] converting the battery energy storage value constraint into the battery power constraint based on the battery rated capacity.

[0020] In an implementation manner, the total loss function is a weighted function of a battery capacity loss function, a generator power loss function and a generator start-stop loss function, wherein the battery capacity loss function is related to the battery power, the generator power loss function is related to the generator power, and the generator start-stop loss function is used to represent a loss brought to the generator due to starting and stopping the generator.

[0021] In an implementation manner, the battery capacity loss function is constructed, including:

[0022] constructing a battery average power function of the battery about battery charging and discharging power based on a battery charging power and a battery discharging power in a charging and discharging cycle of the battery;

[0023] constructing a depth of discharge function about battery charging and discharging power based on the battery rated capacity and the battery charging power and the battery discharging power;

[0024] constructing a battery life loss function based on the battery average power function and the depth of discharge function;

[0025] constructing the battery capacity loss function based on the battery life loss function, the depth of discharge function and the battery average power function.

[0026] In an implementation manner, the construction of the generator start-stop loss function comprises:

[0027] The variables corresponding to the generator starting action and the variables corresponding to the generator stopping action are weighted to obtain the generator start-stop loss function.

[0028] In an implementation manner, based on the battery-generator combined power constraint and the sailing speed constraint and the battery power constraint, the sailing speed, the generator start-stop state, the battery power and the generator power are optimized with the total loss function as an optimization target, comprising:

[0029] Based on the battery power constraint, the value of the battery power is optimized to optimize the value of the battery capacity loss function;

[0030] Based on the battery-generator combined power constraint, the value of the generator power is optimized to optimize the value of the generator power loss function;

[0031] The value of the generator start-stop loss function is optimized by optimizing the generator start-stop state;

[0032] The value of the total loss function is optimized by optimizing the value of the battery capacity loss function, optimizing the value of the generator power loss function and optimizing the value of the generator start-stop loss function, so that the total loss function reaches a minimum value, to obtain the number of times of the optimized generator start-stop state, the value of the optimized battery power and the value of the optimized generator power;

[0033] Based on the sailing speed constraint and the value of the optimized battery power and the value of the optimized generator power, the value of the optimized sailing speed is obtained.

[0034] In a second aspect, the embodiments of the present application also provide an electric ship energy optimization device, wherein the device comprises the following components:

[0035] A sailing speed constraint module is configured to obtain a voyage distance to be sailed by a ship, obtain a total sailing time set for the ship in advance, and construct a sailing speed constraint of the ship based on the voyage distance and the total sailing time.

[0036] A power combined constraint module is configured to construct a propulsion power constraint of the ship based on the sailing speed constraint, and construct a battery-generator combined power constraint based on the propulsion power constraint.

[0037] A battery power constraint module is configured to obtain a rated capacity of a battery, and construct a battery power constraint based on the rated capacity of the battery.

[0038] An optimization module is configured to obtain a total loss function constructed based on the battery power and the generator power of the ship and a generator start-stop state related to the generator power, and optimize the sailing speed, the generator start-stop state, the battery power and the generator power based on the battery-generator combined power constraint, the sailing speed constraint and the battery power constraint, and taking the total loss function as an optimization target.

[0039] In a third aspect, an embodiment of the present application further provides a terminal device, which comprises a memory, a processor, and an electric ship energy optimization program stored in the memory and executable on the processor, and the processor implements the steps of the electric ship energy optimization method when executing the electric ship energy optimization program.

[0040] In a fourth aspect, an embodiment of the present application further provides a computer readable storage medium, which stores an electric ship energy optimization program, and the processor implements the steps of the electric ship energy optimization method when executing the electric ship energy optimization program.

[0041] Beneficial effects: The present application firstly constructs a sailing speed constraint based on the voyage distance and the set total sailing time, that is, the constraint that the ship sails at what speed to sail the voyage distance within the specified total sailing time, and then derives a joint constraint of the battery power and the generator power based on the sailing speed constraint, that is, the power of the battery power and the generator power added together reaches how much to make the sailing speed be within the sailing speed constraint. The present application also constructs a battery power constraint based on the rated capacity of the battery to ensure that the battery capacity does not exceed the rated capacity, thereby reducing the battery loss. Finally, the total loss function of the ship is optimized under the joint constraint, the sailing speed constraint and the battery power constraint to optimize the sailing speed, the generator start-stop state, the battery power and the generator power. From the above analysis, the present application can ensure that the ship completes the sailing task (the moving distance of the ship within the specified total sailing time reaches the voyage distance) within the specified total sailing time by optimizing the sailing speed, and reduce the battery loss by optimizing the battery power, so the present application can balance the sailing task and reduce the battery loss, that is, the present application can not only ensure that the ship completes the sailing task, but also reduce the battery loss, thereby improving the sailing efficiency of the ship. BRIEF DESCRIPTION OF DRAWINGS

[0042] Figure 1 is a whole flowchart of the present application;

[0043] Figure 2 is an electric power system structure diagram of an all-electric ship in an embodiment of the present application;

[0044] Figure 3 is a battery discharge depth schematic diagram in an embodiment of the present application;

[0045] Figure 4 A ship voyage scheduling diagram in an embodiment of the present application;

[0046] Figure 5 A ship energy scheduling diagram in an embodiment of the present application;

[0047] Figure 6 A structure diagram of an electric ship energy optimization device provided by the present application;

[0048] Figure 7 An internal structure principle block diagram of a terminal device provided by an embodiment of the present application. DETAILED DESCRIPTION

[0049] The technical solutions in the present application are described clearly and completely below in combination with embodiments and the accompanying drawings. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor fall within the scope of the present application.

[0050] It is found through research that all-electric ships are gradually applied in inland shipping and offshore transportation scenarios due to their zero emissions and low noise advantages. In order to extend the voyage and improve the operation efficiency, the current ships are equipped with hybrid electric propulsion systems composed of energy storage battery systems and auxiliary generators. At the same time, the energy scheduling and voyage management of the ship increasingly rely on intelligent optimization methods to improve the overall energy efficiency and system reliability.

[0051] The prior art optimizes the route and the sailing speed to ensure that the ship completes the sailing task within the specified sailing time, but the sailing speed is related to the generator power and the battery power. The prior art does not consider the battery power loss of the battery while optimizing the sailing speed in order to complete the sailing task, thereby making it difficult to balance the battery loss while optimizing the sailing speed.

[0052] Embodiment one, to solve the above technical problems, provides an electric ship energy optimization method, device, equipment and medium, solves the problem that the prior art reduces the ship sailing efficiency due to not considering the battery loss.

[0053] The electric ship energy optimization method of the present embodiment can be applied to a terminal device, which can be a terminal product with data processing function, such as a ship controller, etc. In the present embodiment, as shown in Figure 1 The electric ship energy optimization method specifically includes the following steps:

[0054] S100, obtaining a voyage distance to be sailed by a ship, obtaining a total sailing time set in advance for the ship sailing, and constructing a sailing speed constraint of the ship based on the voyage distance and the total sailing time.

[0055] S200, based on the speed constraint, construct the ship's propulsion power constraint, and based on the propulsion power constraint, construct the battery-generator combined power constraint;

[0056] S300: Obtain the rated capacity of the battery and construct a battery power constraint based on the rated capacity of the battery;

[0057] S400: Obtain the total loss function based on the ship's battery power, generator power, and generator start / stop status related to the generator power; and optimize the speed, generator start / stop status, battery power, and generator power based on the combined battery-generator power constraint, the speed constraint, and the battery power constraint, with the total loss function as the optimization objective.

[0058] The vessel in this embodiment is a fully electric vessel, and the electrical system structure diagram of the fully electric vessel is as follows. Figure 2 As shown, from Figure 2 As can be seen from this, the power system of an all-electric ship includes an energy storage battery power system, a generator power system, a service load power system, a propulsion load power system, and an energy management system. The navigation optimization method based on S100, S200, S300, and S400 is located in the energy management system. The energy management system optimizes the generator power, optimizes the battery power, optimizes the speed required for forward propulsion of the ship, and optimizes the generator start-stop state based on this navigation optimization method.

[0059] The ship speed constraint in step S100 is constructed based on formulas (1), (2) and (3).

[0060] (1)

[0061] (2)

[0062] (3)

[0063] In the formula, The representative ship in The sailing distance needs to be determined at all times. The representative ship in The sailing distance needs to be determined at all times. The representative ship in The speed at any moment, Representing the Time and the The duration between moments Represents starting point To the finish line The voyage distance (this voyage distance is the voyage distance that the ship needs to travel in step S100). the actual distance to be completed by the ship within the total set sailing time, is represented by the total set sailing time, the minimum sailing speed value of the ship, the maximum sailing speed value that can be achieved by the ship during sailing.

[0064] Equation (2) defines the actual distance to be sailed by the ship (the actual distance is ) within the total set sailing time (the total set sailing time is ), and is composed of a plurality of , so that the sailing distance to be completed by the ship in each is defined by equation (2), the sailing distance to be completed by the ship in each is in equation (1), that is, the size of is defined to limit the size of in equation (1), and further to limit the size of in equation (1), that is, the size of is defined by equation (1) and equation (2) together, and equation (3) further defines the size of , so that the sailing speed constraint in step S100 can be obtained according to equation (1), equation (2) and equation (3), that is, the size of is defined by equation (1), equation (2) and equation (3).

[0065] The and in equation (1), equation (2) and equation (3) are known, and and are also known, and is divided into a plurality of , so that is known, and since the actual distance to be completed by the ship in is , which is greater than , the sailing distance to be completed by the ship in (the sailing distance is ) is further limited, so that the size of is limited, and is known, so that the size of is limited by equation (1) to form one of the limiting conditions of , and the limiting condition is combined with equation (3) to form a limiting condition for Size constraints. Formula (3) sets upper and lower limits on the ship's speed at each moment to ensure navigation safety and seaworthiness.

[0066] In step S200, based on the speed constraint, the propulsion power constraint of the ship is constructed, that is, the magnitude of the propulsion power is constrained according to formula (4).

[0067] (4)

[0068] In the formula, The representative ship in The propulsion power at any given moment; propulsion power is used to move the ship forward. It represents the meaning of moving forward. Represents linear parameters. Represents the exponential parameter. and The size of each can be a specified value, where The value can be 3. Since the ship speed constraint in step S100 has already limited the speed... The size, therefore the speed Substituting the magnitude into formula (4) yields the propulsion power. The maximum and minimum values ​​of the propulsion power can be constructed based on the speed constraint using formula (4).

[0069] The step S200, which constructs a combined battery-generator power constraint based on the propulsion power constraint, includes: obtaining the power of the electrical equipment required to supply power to the ship; constructing the power supply that the ship can provide based on the sum of the ship's battery power and generator power; determining the power supply constraint based on the power of the electrical equipment and the propulsion power constraint, and using the power supply constraint as the combined battery-generator power constraint.

[0070] (5)

[0071] In the formula, The generator is in the The output power of the generator at time t, the generator at time t The output power at any given time is the generator power. This represents a generator, which is used to charge batteries. This represents the power consumption of the electrical equipment. This equipment requires a generator or battery to provide power. Figure 2 Service load in Representative services. Represents battery power. Represents batteries. , represents the charging power of the battery, represents the meaning of charging, represents the discharging power of the battery, represents the meaning of discharging, when the battery is in a discharging state at the moment, the value of is zero, the battery power the value of is equal to the discharging power of the battery at the moment, when the battery is in a charging state at the moment, the value of is zero, the battery power the value of is a negative value, and the size of is equal to the charging power of the battery the size of.

[0072] represents the sum of the battery power and the generator power, since only the battery and the generator can provide power on the ship, the power that can be provided by the ship to the outside.

[0073] is known, the constraint condition of has been solved, so the battery generator combined power constraint, that is, the constraint of the sum of the battery power and the generator power, can be solved by formula (5), which is used to limit the value range of the sum of the battery power and the generator power.

[0074] In step S300, the battery power constraint is constructed based on the battery rated capacity, including: obtaining a set battery energy storage value constraint; converting the battery energy storage value constraint into a battery power constraint based on the battery rated capacity.

[0075] That is, the battery power constraint is obtained by formula (6), formula (7) and formula (8), which is used to limit the value range of the battery power.

[0076] ; (6)

[0077] ; (7)

[0078] ; (8)

[0079] In the formula, represents the battery energy storage value of the battery at the moment, represents the battery energy storage value of the battery at the moment, represents the battery rated capacity, which is a fixed known value for the same battery, This represents the minimum energy storage capacity of the battery. Represents the maximum energy stored in the battery. Represents the minimum power of the battery. This represents the battery's maximum power, when the battery is in its [number]th [period]. If the battery is in a charging state at a certain time, then the minimum power is the minimum power when the battery is charging, and the maximum power is the maximum power when the battery is charging; when the battery is in the charging state at a certain time... If the battery is in a discharge state at any given time, then the minimum power is the minimum power when the battery is discharging, and the maximum power is the maximum power when the battery is discharging.

[0080] Formula (7) limits The size will Substitute the size into formula (6), formula (8) and substitute... The subsequent formula (6) together constitutes the battery power constraint.

[0081] In this embodiment, the total loss function in step S400 is obtained through formula (9). :

[0082] (9)

[0083] In the formula, It means the sum total. Represents the generator power loss function. This represents the battery capacity loss function. This represents the generator start-up and shutdown loss function, which indicates the losses incurred by the generator due to starting and stopping the generator. This represents the start operation. This indicates that the operation has stopped.

[0084] Among them, the battery capacity loss function The construction includes the following specific steps S401, S402, S403, and S404:

[0085] S401, based on the battery charging power and battery discharging power, constructs the battery average power function with respect to the battery charging and discharging power during the charge and discharge cycle. :

[0086] (10)

[0087] In the formula, represent Charging time during each charge / discharge cycle represent Discharge duration within each charge / discharge cycle.

[0088] S402, constructing a discharge depth function of the battery charge-discharge power based on the battery rated capacity (battery rated capacity is represented by ) and the battery charging power (battery charging power is represented by ) and the battery discharging power (battery discharging power is represented by ).

[0089] That is, the discharge depth function is constructed according to formula (11) :

[0090] ; (11)

[0091] As shown in Figure 3 , the battery discharge depth represents the maximum change range of the battery energy storage in a complete charging or discharging event of the battery.

[0092] S403, constructing a battery life loss function based on the battery average power function and the discharge depth function.

[0093] That is, the battery life loss function is constructed according to formula (12) :

[0094] ; (12)

[0095] The battery life loss is the remaining life of the battery at the moment, and the remaining life is the remaining use time of the battery, representing the rated use time of the battery, representing the battery discharge depth; and are two fitting coefficients related to the battery discharge depth, represents the base of the natural logarithm, represents a correction function of the average power on the battery use time.

[0096] ; (13)

[0097] In the formula, and represent two coefficients related to power, respectively.

[0098] S404, constructing a battery capacity loss function based on the battery life loss function, the discharge depth function and the battery average power function.

[0099] That is, the battery capacity loss function is constructed by formula (14) :

[0100] ; (14)

[0101] wherein, represents the cost of the battery system per unit capacity, represents the total number of charge and discharge events, the number of charge and discharge events reaches the required time length is that is .

[0102] wherein, the generator start-stop loss function is constructed by: weighting the variable corresponding to the generator starting action and the variable corresponding to the generator stopping action, to obtain the generator start-stop loss function.

[0103] that is, the generator power loss function is constructed by formula (15):

[0104] ; (15)

[0105] wherein, represents the binary variable corresponding to the starting operation of the generator, represents the weight of , represents the binary variable corresponding to the stopping operation of the generator, represents the weight of .

[0106] The embodiment constructs the generator power loss function by formula (16):

[0107] ; (16)

[0108] wherein, and respectively represent the quadratic term coefficient and the linear term coefficient of , represents the constant term coefficient.

[0109] Under the battery-generator combined power constraint, the speed constraint and the battery power constraint, the value of when the total loss function reaches the minimum value, the value of , the value of and the value of , since the value of and the value of are substituted into formula (5), the value of can be calculated, and the value of is substituted into formula (4) to calculate the value of the speed .

[0110] ​​Embodiment two, based on embodiment one, not only adds generator power constraint in addition to the three constraints of battery generator combined power constraint, speed constraint and battery power constraint, calculates the total loss function corresponding to the minimum value, corresponding to the minimum value, corresponding to the minimum value, corresponding to the minimum value and speed corresponding to the minimum value.

[0111] According to formula (17), formula (18), formula (19), formula (20) and formula (21), the motor power constraint can be obtained:

[0112] ; (17)

[0113] ; (18)

[0114] ; (19)

[0115] ; (20)

[0116] ; (21)

[0117] In the formula, represents the minimum power of the generator, represents the maximum power of the generator, represents the running state corresponding to the running state of the generator at the time, represents the running state corresponding to the running state of the generator at the time, the running state represents whether the generator is in the starting state, represents the power of the generator at the time, represents the allowed starting slope of the generator, represents the allowed stopping slope of the generator, represents the ship climbing rate, represents the ship descending rate.

[0118] Embodiment three, based on embodiment one or embodiment two, according to the value of corresponding to the minimum value, corresponding to the minimum value, corresponding to the minimum value, corresponding to the minimum value and speed ​The value generation includes a voyage and energy scheduling strategy, which is used to guide the intelligent collaborative control of voyage scheduling and energy management in the actual operation of the all-electric ship, ultimately improving energy efficiency and prolonging battery life.

[0119] As shown in the voyage optimization scheduling Figure 4 , the voyage scheduling optimization result realizes the orderly arrangement of ship acceleration, uniform speed sailing, deceleration and berthing through segmented control of the sailing speed. Among them, the scheduling period is divided into departure segment , cruising segment , berthing segment and berthing segment , forming a periodic sailing mode to match the task demand and energy consumption characteristics.

[0120] As shown in the energy management energy optimization scheduling Figure 5 , it can be known from Figure 5 that the balance between the generator power, the energy storage battery system power and the load power is realized through energy scheduling optimization. Figure 5 The columnar stacking form is adopted in the to show the change relationship of each power component with time, and the propulsion segment participates in discharging to assist the load power supply. By reasonably controlling the energy storage output, the ship system realizes the optimization of generator start-stop and the dynamic scheduling of energy storage charging and discharging, effectively relieving the energy supply pressure.

[0121]

[0121] The embodiment also provides a certain device, as shown in Figure 6 , the device comprises the following components:

[0122] The speed constraint module 01 is used to obtain the voyage distance of the ship to be sailed, obtain the total sailing time set for the ship sailing in advance, and construct the speed constraint of the ship based on the voyage distance and the total sailing time;

[0123] The power joint constraint module 02 is used to construct the propulsion power constraint of the ship based on the speed constraint, and construct the battery-generator joint power constraint based on the propulsion power constraint;

[0124] The battery power constraint module 03 is used to obtain the rated capacity of the battery, and construct the battery power constraint based on the rated capacity of the battery;

[0125] The optimization module 04 is used to obtain the total loss function constructed based on the battery power and the generator power of the ship and the generator start-stop state related to the generator power, and optimize the sailing speed, the generator start-stop state, the battery power and the generator power based on the battery-generator joint power constraint, the speed constraint and the battery power constraint, with the total loss function as the optimization target.

[0126] Based on the above embodiments, the application further provides a terminal device, a principle block diagram of which can be shown in Figure 7 The terminal device includes a processor, a memory, a network interface, and a display screen connected through a system bus. The processor of the terminal device is configured to provide computing and control capabilities. The memory of the terminal device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operating system and the computer program in the non-volatile storage medium to run. The network interface of the terminal device is configured to communicate with an external terminal through a network connection. The computer program is executed by the processor to implement an electric ship energy optimization method. The display screen of the terminal device can be a liquid crystal display screen or an electronic ink display screen.

[0127] Those skilled in the art can understand that Figure 7 The principle block diagram shown in the above embodiments is only a block diagram of part of the structure related to the application scheme, and does not constitute a limitation on the terminal device to which the application scheme is applied. The specific terminal device can include more or fewer components than those shown in the diagram, or combine certain components, or have a different component arrangement.

[0128] In one embodiment, a terminal device is provided, which includes a memory, a processor, and an electric ship energy optimization program stored in the memory and executable on the processor. When the processor executes the electric ship energy optimization program, the following operation instructions are implemented:

[0129] Obtain a voyage distance to be traveled by a ship, obtain a total voyage time set in advance for the ship to travel, and construct a speed constraint of the ship based on the voyage distance and the total voyage time;

[0130] Construct a propulsion power constraint of the ship based on the speed constraint, and construct a battery-generator combined power constraint based on the propulsion power constraint;

[0131] Obtain a rated capacity of a battery, and construct a battery power constraint based on the rated capacity of the battery;

[0132] Obtain a total loss function constructed based on a battery power and a generator power of the ship and a generator start-stop state related to the generator power, and optimize a speed, the generator start-stop state, the battery power, and the generator power with the total loss function as an optimization target based on the battery-generator combined power constraint, the speed constraint, and the battery power constraint.

[0133] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program. The computer program can be stored in a non-volatile computer readable storage medium, and when the computer program is executed, the processes of the above-mentioned embodiments of the methods can be included. Any reference to memory, storage, database or other medium used in each embodiment of the present application can include non-volatile and / or volatile memory. Non-volatile memory can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM) or flash memory. Volatile memory can include random access memory (RAM) or external cache memory. As an illustration but not limitation, RAM is available in various forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDR SDRAM), enhanced SDRAM (ESDRAM), Synchlink DRAM (SLDRAM), Rambus direct RAM (RDRAM), direct RAM bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM), etc.

[0134] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, and not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that: it can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement for part of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A method for optimizing the energy of electric ships, characterized in that, include: Obtain the distance the ship needs to travel, obtain the total travel time preset for the ship's travel, and construct the ship's speed constraint based on the distance and the total travel time; Based on the speed constraint, the ship's propulsion power constraint is constructed, and based on the propulsion power constraint, the battery-generator combined power constraint is constructed. Obtain the rated capacity of the battery, and construct a battery power constraint based on the rated capacity of the battery; Obtain a total loss function based on the ship's battery power, generator power, and generator start-stop state related to the generator power. The total loss function includes a battery capacity loss function. Based on the joint power constraints of the battery and generator, the speed constraints, and the battery power constraints, optimize the speed, generator start-stop state, battery power, and generator power with the total loss function as the optimization objective. The construction of the battery capacity loss function includes: Based on the battery charging power and battery discharging power, a battery average power function with respect to the battery charging and discharging power is constructed during the charge and discharge cycle. Based on the battery's rated capacity, charging power, and discharging power, a depth of discharge function is constructed regarding the battery's charging and discharging power. : In the formula, Represents the battery's rated capacity. Represents battery charging power. Represents the battery discharge power. represent Charging time during each charge / discharge cycle represent Discharge duration during each charge / discharge cycle; A battery lifetime loss function is constructed based on the battery average power function and the depth of discharge function. : This represents the battery's rated operating time. Represents the depth of battery discharge; and These are two fitting coefficients related to the depth of battery discharge. The base of the natural logarithm. A correction function representing the impact of average power on battery life; Based on the battery life loss function, the depth of discharge function, and the battery average power function, a battery capacity loss function is constructed. : In the formula, Represents the cost per unit capacity of the battery system. This represents the total number of charge / discharge events; the number of charge / discharge events reaches [a certain threshold]. The required time is , This represents the average power function of the battery.

2. The energy optimization method for electric ships as described in claim 1, characterized in that, Based on the aforementioned propulsion power constraint, a joint power constraint for the battery and generator is constructed, including: Obtain the power consumption of the electrical equipment required by the ship; The total power output of a ship is determined by the sum of its battery power and generator power. Based on the power of the electrical equipment and the propulsion power constraints, the constraints on the power supply are determined, and the constraints on the power supply are used as the combined power constraints of the battery and generator.

3. The energy optimization method for electric ships as described in claim 1, characterized in that, Based on the battery's rated capacity, a battery power constraint is constructed, including: Obtain the set battery energy storage value constraint; Based on the battery's rated capacity, the battery energy storage value constraint is converted into a battery power constraint.

4. The energy optimization method for electric ships as described in claim 1, characterized in that, The total loss function is a weighted function of the generator power loss function and the generator start-stop loss function. The battery capacity loss function is related to the battery power, the generator power loss function is related to the generator power, and the generator start-stop loss function is used to characterize the losses caused to the generator by starting and stopping the generator.

5. The energy optimization method for electric ships as described in claim 4, characterized in that, The construction of the generator start-stop loss function includes: By weighting the variables corresponding to the generator starting action and the generator stopping action, the generator start-stop loss function is obtained.

6. The energy optimization method for electric ships as described in claim 4, characterized in that, Based on the combined power constraints of the battery and generator, the speed constraints, and the battery power constraints, and with the total loss function as the optimization objective, the following optimizations are made: Speed, generator start / stop status, battery power, and generator power are optimized. Based on the battery power constraint, the value of the battery capacity loss function is optimized by optimizing the value of the battery power. Based on the combined power constraint of the battery and generator, the value of the generator power loss function is optimized by optimizing the value of the generator power. The value of the generator start-stop loss function is optimized by optimizing the generator start-stop state; By optimizing the values ​​of the battery capacity loss function, the generator power loss function, and the generator start-stop loss function, the value of the total loss function is optimized to minimize the total loss function, thereby obtaining the optimized number of generator start-stop states, the optimized battery power value, and the optimized generator power value. Based on the speed constraint, the optimized battery power value, and the optimized generator power value, the optimized speed value is obtained.

7. An energy optimization device for electric ships, characterized in that, The device comprises the following components: The speed constraint module is used to obtain the distance the ship needs to travel, obtain the total travel time preset for the ship's travel, and construct the ship's speed constraint based on the distance traveled and the total travel time. A power joint constraint module is used to construct the ship's propulsion power constraint based on the speed constraint, and to construct the battery generator joint power constraint based on the propulsion power constraint; A battery power constraint module is used to obtain the rated capacity of the battery and construct a battery power constraint based on the rated capacity of the battery. An optimization module is used to obtain a total loss function based on the ship's battery power and generator power, as well as the generator start-stop state related to the generator power. The total loss function includes a battery capacity loss function. Based on the joint power constraints of the battery and generator, the speed constraints, and the battery power constraints, the module optimizes the speed, generator start-stop state, battery power, and generator power with the total loss function as the optimization objective. The construction of the battery capacity loss function includes: Based on the battery charging power and battery discharging power, a battery average power function with respect to the battery charging and discharging power is constructed during the charge and discharge cycle. Based on the battery's rated capacity, charging power, and discharging power, a depth of discharge function is constructed regarding the battery's charging and discharging power. : In the formula, Represents the battery's rated capacity. Represents battery charging power. Represents the battery discharge power. represent Charging time during each charge / discharge cycle represent Discharge duration during each charge / discharge cycle; A battery lifetime loss function is constructed based on the battery average power function and the depth of discharge function. : This represents the battery's rated operating time. Represents the depth of battery discharge; and These are two fitting coefficients related to the depth of battery discharge. The base of the natural logarithm. A correction function representing the impact of average power on battery life; Based on the battery life loss function, the depth of discharge function, and the battery average power function, a battery capacity loss function is constructed. : In the formula, Represents the cost per unit capacity of the battery system. This represents the total number of charge / discharge events; the number of charge / discharge events reaches [a certain threshold]. The required time is , This represents the average power function of the battery.

8. A terminal device, characterized in that, The terminal device includes a memory, a processor, and an electric ship energy optimization program stored in the memory and executable on the processor. When the processor executes the electric ship energy optimization program, it implements the steps of the electric ship energy optimization method as described in any one of claims 1-6.

9. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores an electric ship energy optimization program, which, when executed by a processor, implements the steps of the electric ship energy optimization method as described in any one of claims 1-6.

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