Direct current integrated power system ship economy dispatching calculation method

Abstract

The present application relates to a kind of DC integrated power system ship economy scheduling calculation method, establish DC integrated power system ship power system mathematical model, establish DC integrated power system ship thermal system mathematical model, while meeting the demand of ship power load and heat load, with the operation cost and carbon emission of DC integrated power system ship lowest as target, determine the objective function of DC integrated power system ship economy scheduling based on fuel cell waste heat recovery, under the constraint condition of hydrogen fuel cell waste heat recovery DC integrated power system, with the hourly power output of ship diesel generator system, hydrogen fuel cell initial state, indoor temperature, ship speed as variable, optimal variable combination is obtained using optimization algorithm for scheduling.The present application better utilizes hydrogen fuel cell waste heat, further improves the fuel efficiency of ship diesel generator, thereby reduces fuel cost, makes ship power system and thermal system cooperate with each other, efficiently operates.

Description

Technical Field

[0001] This invention relates to power system operation and ship technology, and particularly to a method for calculating the economic dispatch of ships in a DC integrated power system based on waste heat recovery from hydrogen fuel cells. Background Technology

[0002] Ocean shipping accounts for approximately 3% of global CO2 emissions and nearly 15% of NO emissions. x A study by the International Maritime Organization (IMO) indicates that global shipping emissions will further increase by 2050 if left unchecked. In response, the IMO has introduced a series of new ship energy efficiency regulations and pollutant emission amendments. The shipping industry has begun in-depth energy conservation and emission reduction reforms, on the one hand, by utilizing new energy sources as alternative energy sources for existing ships, and on the other hand by seeking new technologies to improve ship energy efficiency and environmental benefits.

[0003] Hydrogen fuel cells offer advantages such as high efficiency, no need for mechanical transmission components, and low emissions of harmful gases. Introducing hydrogen fuel cells into traditional ship power plants can reduce ships' excessive reliance on fossil fuels and alleviate their greenhouse gas emission burden. However, the new DC integrated power system for ships, encompassing diesel generator systems, hydrogen fuel cells, electric propulsion loads, and living loads, is a multi-dimensional complex system with multiple variables coupled, complex operation, and high uncertainty. A key challenge in the economic dispatch strategy for DC integrated power systems for ships is how to achieve optimization goals in terms of economy, reliability, and environmental protection by rationally adjusting the output of generation and energy storage units while meeting load demands and system operation constraints.

[0004] Currently, hydrogen fuel cells are used in vehicles such as automobiles and rail, but their application in the marine sector is still in its early stages, especially with little attention paid to waste heat recovery from hydrogen fuel cells. Addressing the new field of economical ship scheduling considering waste heat recovery from hydrogen fuel cells, this invention pioneers a method for economical ship scheduling using a DC integrated power system based on hydrogen fuel cell waste heat recovery. Utilizing hydrogen fuel cells as energy storage devices within the DC integrated power system for ships, this method fully leverages waste heat recovery from hydrogen fuel cells while improving the energy efficiency of ship operation and reducing pollution emissions through a rational ship economical operation scheduling framework. Summary of the Invention

[0005] To improve the energy efficiency of ships operating under DC integrated electric power systems and reduce pollution emissions, an economic scheduling calculation method for ships with DC integrated electric power systems is proposed. This method utilizes hydrogen fuel cells as energy storage devices within the ship's DC integrated electric power system. Simultaneously, it integrates a waste heat utilization system for the hydrogen fuel cell system, using the reaction water produced by the hydrogen fuel cell as a heat source to supply the heating module and transfer it to relevant modules. While ensuring the stable operation of the hydrogen fuel cell, the heat energy generated by the heating module is used to power the ship's cabins, thus fully utilizing the waste heat of the hydrogen fuel cell to achieve energy conservation and emission reduction for ships.

[0006] The technical solution of this invention is: a method for calculating the economic dispatch of ships in a DC integrated power system, specifically including the following steps:

[0007] 1) Establish a mathematical model of the ship's power system for a DC integrated power system, including mathematical models of diesel generators, hydrogen fuel cells, electric propulsion loads, and living loads;

[0008] 2) Establish a mathematical model of the ship's thermal system using a DC integrated power system, including the hydrogen fuel cell supplying heat to the heat load, the electrothermal conversion device, and the mathematical model of the heat load;

[0009] 3) Based on steps 1) and 2), the steps for establishing the economic dispatch model of the DC integrated power system for ships are as follows: While meeting the ship's power load and heat load requirements, the objective function for economic dispatch of the DC integrated power system for ships based on fuel cell waste heat recovery is determined with the goal of minimizing the operating cost and carbon emissions of the DC integrated power system for ships. Under the constraint of the DC integrated power system with hydrogen fuel cell waste heat recovery, the hourly power output of the ship's diesel generator system, the initial state of the hydrogen fuel cell, the indoor temperature, and the ship's speed are used as variables, and an optimization algorithm is used to obtain the optimal combination of variables for dispatch.

[0010] Furthermore, the method for establishing the mathematical model of the diesel generator in step 1) is as follows: The unit fuel consumption function of the diesel generator is an important indicator for evaluating the working efficiency of the diesel engine. Its unit fuel consumption function is fitted by a binomial formula, as shown below:

[0011]

[0012] Among them, a 0i a 1i a 2i Here are the parameters for the i-th generator; P DG,i Let be the output power of the i-th diesel generator; the fuel consumption FC of the diesel generator is derived from the unit fuel consumption function SFC of the diesel generator system, as follows:

[0013] Furthermore, the method for establishing the mathematical model of the hydrogen fuel cell in step 1) is as follows: The hydrogen fuel cell acts as an energy storage system, balancing the power of the power system in a DC integrated power system ship. When there is excess power, the hydrogen fuel cell achieves power balance through charging, as shown in the following equation:

[0014]

[0015] When the power of the ship's electric power system is insufficient in a DC integrated power system, the hydrogen fuel cell supplies power to the ship's load by discharging, as shown in the following formula:

[0016]

[0017] in, This represents the remaining energy of the hydrogen fuel cell at time t. Power for charging hydrogen fuel cells; For hydrogen fuel cell discharge power; η ch For hydrogen fuel cell charging efficiency; η dc Δt represents the discharge efficiency of the hydrogen fuel cell; Δt represents the time interval.

[0018] Furthermore, the method for establishing the mathematical model of electric propulsion load in step 1) is as follows: the power demand of electric propulsion load has a non-linear relationship with ship speed, as shown in the following formula:

[0019]

[0020] in, V represents the power demand of the electric propulsion system at time t. t Let t be the ship speed at time t; c1 is the conversion coefficient between the ship speed to the power of c2 and the propeller power; c2 is a parameter related to the ship's electric propulsion system, which is related to the scale and model of the electric propulsion system.

[0021] Furthermore, the mathematical model establishment method for the ship's thermal system in step 2) is as follows: the hydrogen fuel cell serves as the heat source in the ship's DC integrated power system to supply heat to the heat load, so the heat formula is approximately expressed as:

[0022] Q st (t)≈P FC (6)

[0023] Among them, Q st (t) represents the heat generated by the hydrogen fuel cell; P FC This refers to the discharge power of a hydrogen fuel cell.

[0024] In ships with DC integrated electric power systems, electric boilers, acting as electrothermal conversion devices, generate heat with constant efficiency. Their mathematical model is as follows:

[0025] Q EB(t)=COP EB ·P EB (t) (7)

[0026] Among them, Q EB For converting heat in electric boilers; P EB Input power for the electric boiler; COP EB For electric boiler conversion efficiency;

[0027] The mathematical model for heat load in a ship with a DC integrated power system is as follows:

[0028]

[0029]

[0030] In the formula, Let t be the indoor temperature (°C). Let t be the outdoor temperature (°C). Let t be the water temperature (°C) of the thermal energy system at time t; Let t be the heat energy generated by the outdoor temperature at time t (kWh); The indoor thermal energy at time t+1 (kWh); S ex The outer surface area of ​​a DC integrated power system ship (m²) 2 ); K h is the thermal convection coefficient; c is the specific heat capacity (kWh / ℃) of the ship's hot water system in the DC integrated power system; Q w To generate heat energy (kWh) from hot water in the thermal energy system; c air Specific heat capacity of air (kWh / ℃); c e Specific heat capacity of water (kWh / ℃); c r ρ is the thermal conductivity of the insulation layer; ρ is the air density; U is the ship volume; q is the hot water heat transfer coefficient in the thermal energy system.

[0031] Furthermore, the objective function for the economical scheduling of ships in the DC integrated power system based on fuel cell waste heat recovery in step 3) is specifically expressed as:

[0032]

[0033]

[0034]

[0035] In the formula, f1 is the operating cost; f2 is the carbon emission; Cost MT For maintenance costs; Cost DG,i The fuel consumption cost of the i-th diesel generator; GE DG,iThe emissions from the i-th diesel generator are represented by Ng; Ng represents the total number of diesel generators in the DC integrated power system; Price represents the emissions from the i-th diesel generator. fuel For ship fuel costs; and K represents the output power and rated power of the i-th diesel generator at time t, respectively; ES For the operating cost of the energy storage system; K EB Cost of converting thermal energy to electrical energy; Let be the heat absorbed by the thermal energy storage at time t; Let t be the amount of heat released by the thermal energy storage. The power consumed by the electrothermal conversion device at time t; Em fuel b is the carbon dioxide conversion coefficient; 0,i b 1,i b 2,i Let be the carbon emission parameters of the i-th diesel generator.

[0036] Furthermore, the constraints of the DC integrated power system for waste heat recovery from the hydrogen fuel cell are specifically expressed as follows:

[0037]

[0038] Q EB -Q st =Q H (14)

[0039]

[0040]

[0041] E ES (0)=E ES (24) = 80% Cap ES (17)

[0042]

[0043]

[0044]

[0045] 0≤V t ≤V max (twenty one)

[0046] In the formula, P EB P represents the power of the electrothermal conversion device. service Power required for domestic load; P propulsion Q represents the power required for electrically driven loads. EB The heat output of the electrothermal conversion device; Q H This represents the total heat of the system. Let be the minimum output power of the i-th diesel generator; Let be the rated power of the i-th diesel generator. ΔP is the climbing power of the diesel generator; Cap ES For energy storage system capacity; ΔT min / ΔT max The minimum / maximum change in indoor temperature; T min / T max The minimum / maximum indoor temperature; δ midD δ represents the allowable distance error between intermediate ports. termD δ represents the allowable distance error between the initial port and the destination port. termD Dis represents the allowable distance error between intermediate ports; term It is the distance between ports; Dis n Dis represents the total voyage distance between the initial port and the final port. nT This represents the actual distance a ship travels between the two ports.

[0047] Furthermore, the optimization algorithm obtains the optimal variable combination. Specifically, it utilizes a multi-objective particle swarm optimization algorithm to solve the economic scheduling of ships in a DC integrated power system. First, variables are initialized to form a population P with N particles. Then, within the constraints of the DC integrated power system with hydrogen fuel cell waste heat recovery, a speed is randomly assigned to each particle. Second, each particle is evaluated based on the economic scheduling objective function of the DC integrated power system based on fuel cell waste heat recovery. Then, it is checked whether the operating cost and pollutant emissions of the DC integrated power system ships are minimized. If not, the particles are updated using speed and position update formulas, generating a new population Q. Subsequently, populations P and Q are integrated to synthesize a new population R, and population R is sorted. After sorting, N optimal particles are reselected for the next iteration. Finally, until the program ends, the final optimized scheduling result is output.

[0048] The beneficial effects of this invention are as follows: The DC integrated power system ship economic dispatch calculation method of this invention effectively and flexibly adjusts the power distribution in the DC integrated power system ship power system, improving the power quality and operating efficiency of the ship power system; through hydrogen fuel cells, the integrated electric propulsion system can be better utilized, improving the fuel efficiency of diesel generators, thereby reducing fuel costs and improving environmental friendliness; through hydrogen fuel cell waste heat recovery and economic dispatch methods, resources can be effectively integrated, enabling the ship power system and thermal system to cooperate and operate efficiently; the economic dispatch method in this invention is not limited to a fixed network structure, has wide applicability and good scalability, and can be applied to different types of ships and even land transportation vehicles. Attached Figure Description

[0049] Figure 1This is a structural diagram of the ship power system of the DC integrated power system containing hydrogen fuel cells of the present invention;

[0050] Figure 2 For the conventional load curve of a DC integrated power system for ships;

[0051] Figure 3 This is a flowchart of the ship economical dispatching method based on waste heat recovery from hydrogen fuel cells according to the present invention. Detailed Implementation

[0052] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. These embodiments are based on the technical solution of the present invention and provide detailed implementation methods and specific operating procedures. However, the scope of protection of the present invention is not limited to the following embodiments.

[0053] like Figure 1 The diagram shows the structural design of a ship's electrical system incorporating a hydrogen fuel cell-based DC integrated power system. The hydrogen fuel cell serves as the energy storage device within this system. Combined with a waste heat utilization system, the reaction water produced by the hydrogen fuel cell is used as a heat source, fed into a heat bus to supply the heating module, which in turn powers related modules. While ensuring stable operation of the hydrogen fuel cell, the heat generated by the heating module powers the ship's cabins, thus fully utilizing the waste heat from the hydrogen fuel cell to achieve energy conservation and emission reduction for the ship.

[0054] A method for calculating the economic dispatch of ships based on the waste heat recovery of hydrogen fuel cells in a DC integrated power system specifically includes:

[0055] A: Mathematical Model of DC Integrated Power System and Ship Power System

[0056] The unit fuel consumption function of a diesel generator is an important indicator for evaluating the working efficiency of a diesel engine. Its unit fuel consumption function can be fitted using a binomial formula, as shown in the following equation:

[0057]

[0058] Among them, a 0i a 1i a 2i Here are the parameters for the i-th generator; P DG,i Let be the output power of the i-th diesel generator.

[0059] The fuel consumption (FC) of a diesel generator can be derived from the unit fuel consumption function (SFC) of the diesel generator system, as shown in the following formula:

[0060]

[0061] Hydrogen fuel cells, as energy storage systems, play a crucial role in power balance within DC integrated electric power systems in ships. When there is excess power, the hydrogen fuel cells achieve power balance through recharging, as shown in the equation:

[0062] When the ship's power system is insufficient in a DC integrated power system, hydrogen fuel cells supply power to the ship's load through discharge, as shown in the following formula:

[0063]

[0064] in, This represents the remaining energy of the hydrogen fuel cell at time t. Power for charging hydrogen fuel cells; For hydrogen fuel cell discharge power; η ch For hydrogen fuel cell charging efficiency; η dc Δt represents the discharge efficiency of the hydrogen fuel cell; Δt represents the time interval.

[0065] The power demand of electric propulsion loads has a non-linear relationship with ship speed, as shown in the following equation:

[0066]

[0067] in, V represents the power demand of the electric propulsion system at time t. t Let t be the ship speed at time t; c1 is the conversion coefficient between the ship speed to the power of c2 and the propeller power; c2 is a parameter related to the ship's electric propulsion system, which is related to the scale and model of the electric propulsion system.

[0068] The living load of a ship equipped with a DC integrated electric power system mainly includes air conditioning, refrigeration, ventilation, lighting, and communication systems. This living load is closely related to the ship's functions and operating conditions, and power requirements vary significantly under different conditions. For example... Figure 2 The figure shows the conventional load curve of a DC integrated power system for ships.

[0069] B: Mathematical Model of Ship Thermal System in DC Integrated Power System

[0070] Hydrogen fuel cells can serve as a heat source for heating loads in ships using DC integrated power systems. Since the actual operating efficiency of the fuel cell stack is generally around 50%, more than half of the input energy is converted into heat. Therefore, the heat generation formula can be approximated as:

[0071] Q st (t)≈P FC (6)

[0072] Among them, Q st (t) represents the heat generated by the hydrogen fuel cell; P FCThis represents the discharge power of the hydrogen fuel cell.

[0073] In ships with DC integrated electric power systems, electric boilers, acting as electrothermal conversion devices, generate heat with constant efficiency. Their mathematical model is as follows:

[0074] Q EB (t)=COP EB ·P EB (t) (7)

[0075] Among them, Q EB For converting heat in electric boilers; P EB Input power for the electric boiler; COP EB This refers to the conversion efficiency of the electric boiler.

[0076] The mathematical model for heat load in a ship with a DC integrated power system is as follows:

[0077]

[0078]

[0079] In the formula, Let t be the indoor temperature (°C). Let t be the outdoor temperature (°C). Let t be the water temperature (°C) of the thermal energy system at time t; Let t be the heat energy generated by the outdoor temperature at time t (kWh); The indoor thermal energy at time t+1 (kWh); S ex The outer surface area of ​​a DC integrated power system ship (m²) 2 ); K h is the thermal convection coefficient; c is the specific heat capacity (kWh / ℃) of the ship's hot water system in the DC integrated power system; Q w To generate heat energy (kWh) from hot water in the thermal energy system; c air Specific heat capacity of air (kWh / ℃); c e Specific heat capacity of water (kWh / ℃); c r ρ is the thermal conductivity of the insulation layer; ρ is the air density; U is the ship volume; q is the hot water heat transfer coefficient in the thermal energy system.

[0080] C: DC Integrated Power System Ship Economic Dispatch Model

[0081] Economic dispatching of ships using a DC integrated power system involves rationally allocating power sources within the power system and heat sources within the thermal system to minimize ship operating costs and pollution emissions while meeting the ship's electrical and thermal load demands. Therefore, the objective function for economic dispatching of ships using a DC integrated power system based on hydrogen fuel cell waste heat recovery can be specifically expressed as:

[0082]

[0083]

[0084]

[0085] In the formula, Cost MT For maintenance costs; Cost DG,i The fuel consumption cost of the i-th diesel generator; GE DG,i Price represents the pollutant emissions from the i-th diesel generator; Ng represents the total number of diesel generators in the DC integrated power system. fuel For ship fuel costs; and K represents the output power and rated power of the i-th diesel generator at time t, respectively; ES For the operating cost of the energy storage system; K EB Cost of converting thermal energy to electrical energy; Let be the heat absorbed by the thermal energy storage at time t; Let t be the heat released by the thermal energy storage. Em represents the power consumed by the electrothermal conversion device at time t. fuel b is the carbon dioxide conversion coefficient; 0,i b 1,i b 2,i Let be the carbon emission parameters of the i-th diesel generator.

[0086] The constraints on the economic dispatch of ships based on the DC integrated power system using hydrogen fuel cell waste heat recovery can be specifically expressed as follows:

[0087]

[0088] Q EB -Q st =Q H (14)

[0089]

[0090]

[0091] E ES (0)=E ES (24) = 80% Cap ES (17)

[0092]

[0093]

[0094]

[0095] 0≤V t ≤V max (twenty one)

[0096] In the formula, P EB P represents the power of the electrothermal conversion device. service Power required for domestic load; P propulsion Q represents the power required for electrically driven loads. EB The heat output of the electrothermal conversion device; Q H This represents the total heat of the system. Let be the minimum output power of the i-th diesel generator; Cap represents the rated power of the i-th diesel generator. ΔP represents the diesel generator's ramp-up power. ES This represents the capacity of the energy storage system. ΔT min / ΔT max The minimum / maximum change in indoor temperature; T min / T max The minimum / maximum indoor temperature; δ midD δ represents the allowable distance error between intermediate ports. termD δ represents the allowable distance error between the initial port and the destination port. termD Dis represents the allowable distance error between intermediate ports; term It is the distance between ports; Dis n Dis represents the total voyage distance between the initial port and the final port. nT This represents the actual distance a ship travels between the two ports.

[0097] D: Economic Dispatch Method for Ships Based on DC Integrated Power Systems with Waste Heat Recovery from Hydrogen Fuel Cells

[0098] As a heuristic global optimization method, Particle Swarm Optimization (PSO) effectively solves multi-objective optimization problems and has received widespread attention and application. The optimization mechanism of PSO evolved from the foraging process of group animals. When flocks of birds or schools of fish forage, they communicate by sharing information with each other, while each individual animal summarizes its own historical experience. The entire group continuously updates its position and direction until it finally finds its target. Based on this, PSO integrates the historical information of the group with the individual experience of each animal, searching for the optimal solution under the guidance of the globally optimal particle and the individual optimal particle. The specific mathematical expression is shown below.

[0099]

[0100] Where k is the current iteration number, v i x is the velocity of the i-th particle; iThe position of the i-th particle; w is the inertial weight; u1 and u2 are learning factors; r1 and r2 represent random numbers varying in [0,1]; p i denoted as the position of the individual optimal particle; g represents the global optimal position.

[0101] This project utilizes a multi-objective particle swarm optimization algorithm to solve the economic scheduling problem of ships in a DC integrated electric power system. The method first initializes variables to form a population P with N particles, including the hourly power output of the onboard diesel generator system, the initial state of the hydrogen fuel cell, the indoor temperature, and the ship's speed. Then, within constraints, a speed is randomly assigned to each particle. Next, each particle is evaluated in conjunction with the objective function. Then, it checks whether the operating cost and pollutant emissions of the DC integrated electric power system ship (Equation 10) are minimized. If not, the particles are updated using the speed and position update formula (Equation 22), generating a new population Q. Subsequently, populations P and Q are integrated to synthesize a new population R, and population R is sorted. After sorting, N optimal particles are reselected for the next iteration. Finally, until the program terminates, the final optimized scheduling result is output. The specific process is as follows: Figure 3 As shown.

[0102] Existing methods for economical ship scheduling typically involve uniformly allocating power generation at the generator end to meet load demand. However, there is currently no research or application of using waste heat recovery from hydrogen fuel cells, combined with optimized control technology, as one of the heat sources of the thermal system for economical ship scheduling.

[0103] The proposed economic dispatching method for ships using a DC integrated electric power system based on waste heat recovery from hydrogen fuel cells can reduce fuel consumption and pollution emissions during ship operation. Taking a ship with a DC integrated electric power system equipped with three 1000kW diesel generators and a 400kW hydrogen fuel cell as an example, the economic dispatching optimization results are shown in Table 1.

[0104] Table 1

[0105] No economic scheduling examples Example of this scheme Fuel consumption cost () 36200 20685 Pollution emissions (kg) 12067 6875

[0106] Table 1 shows that, considering a diesel engine fuel consumption of 181 g / kWh, the average daily fuel cost of the optimized DC integrated power system for ship power systems is 20,685 yuan, with pollutant emissions of 6,875 kg. Compared to a non-economical dispatching scheme, this invention can reduce carbon emissions by 43.03%. Simulation results demonstrate that the ship economical dispatching method based on hydrogen fuel cell waste heat recovery proposed in this scheme can make fuller use of hydrogen fuel cell waste heat recovery, improve ship operation economy and energy utilization, and further solve problems such as high ship fuel consumption, heavy pollution, and low efficiency.

[0107] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A method for calculating the economic dispatch of ships in a DC integrated power system, characterized in that, Specifically, the following steps are included: 1) Establish a mathematical model of the ship's power system using a DC integrated power system, including mathematical models for diesel generators, hydrogen fuel cells, electric propulsion loads, and living loads; the method for establishing the mathematical model of the electric propulsion load is as follows: the power demand of the electric propulsion load has a non-linear relationship with the ship's speed, as shown in the following formula: （5） in, for t Power requirements of the electric propulsion system at all times; for t Ship speed at any time; For ship speed The conversion factor between the power and the thruster power; These are parameters related to the ship's electric propulsion system, which are related to the scale and model of the electric propulsion system. 2) Establish a mathematical model of the ship's thermal system using a DC integrated power system, including the hydrogen fuel cell supplying heat to the heat load, the electrothermal conversion device, and the mathematical model of the heat load; The mathematical model for the ship's thermal system in the DC integrated power system is established as follows: Hydrogen fuel cells serve as the heat source for the ship's thermal load within the DC integrated power system; therefore, the heat formula is approximately expressed as: （6） in, It generates heat for hydrogen fuel cells; This refers to the discharge power of a hydrogen fuel cell. In ships with DC integrated electric power systems, electric boilers, acting as electrothermal conversion devices, generate heat with constant efficiency. Their mathematical model is as follows: （7） in, Converting heat for electric boilers; Input power to the electric boiler; For electric boiler conversion efficiency; The mathematical model for heat load in a ship with a DC integrated power system is as follows: （8） （9） In the formula, For time intervals; for t Indoor temperature at any given time, in °C; for t Outdoor temperature at any time, in °C; for t The water temperature of the thermal energy system at any given time, in °C; for t The heat energy generated by the outdoor temperature at any given time, expressed in kWh. for t+ Indoor thermal energy at moment 1, unit: kWh; The external surface area of ​​a ship with a DC integrated power system is expressed in meters (m²). 2 ; The thermal convection coefficient; Specific heat capacity of the ship's hot water system in a DC integrated power system, in kWh / ℃; The heat energy generated by hot water in a thermal energy system, expressed in kWh; Specific heat capacity of air, in kWh / ℃; Specific heat capacity of water, in kWh / ℃; The thermal conductivity of the insulation layer; air density; U For the volume of the ship; q The heat transfer coefficient of hot water in the thermal energy system; 3) Based on steps 1) and 2), the steps for establishing the economic dispatch model of the DC integrated power system for ships are as follows: While meeting the ship's power load and heat load requirements, the objective function for economic dispatch of the DC integrated power system for ships based on fuel cell waste heat recovery is determined with the goal of minimizing the operating cost and carbon emissions of the DC integrated power system for ships. Under the constraint of the DC integrated power system with hydrogen fuel cell waste heat recovery, the hourly power output of the ship's diesel generator system, the initial state of the hydrogen fuel cell, the indoor temperature, and the ship's speed are used as variables, and an optimization algorithm is used to obtain the optimal combination of variables for dispatch.

2. The method for calculating the economic dispatch of ships in a DC integrated power system according to claim 1, characterized in that, The method for establishing the mathematical model of the diesel generator in step 1) is as follows: The unit fuel consumption function of the diesel generator is an important indicator for evaluating the working efficiency of the diesel engine. Its unit fuel consumption function is fitted by a binomial formula, as shown below: （1） in, , , For the first i Generator parameters; For the first i Output power of the diesel generator; The fuel consumption FC of a diesel generator is derived from the unit fuel consumption function SFC of the diesel generator system, as shown in the following formula: （2）。 3. The method for calculating the economic dispatch of ships in a DC integrated power system according to claim 1, characterized in that, The method for establishing the mathematical model of the hydrogen fuel cell in step 1) is as follows: The hydrogen fuel cell acts as an energy storage system to balance the power of the DC integrated power system in a ship. When there is excess power, the hydrogen fuel cell achieves power balance through charging, as shown in the following equation: （3） When the power of the ship's electric power system is insufficient in a DC integrated power system, the hydrogen fuel cell supplies power to the ship's load by discharging, as shown in the following formula: （4） in, For hydrogen fuel cells t Remaining energy at any given time; Power for charging hydrogen fuel cells; This refers to the discharge power of a hydrogen fuel cell. Improve the charging efficiency of hydrogen fuel cells; For hydrogen fuel cell discharge efficiency; For time intervals.

4. The method for calculating the economic dispatch of ships in a DC integrated power system according to claim 1, characterized in that, The objective function for the economical scheduling of ships in the DC integrated power system based on fuel cell waste heat recovery in step 3) is specifically expressed as follows: （10） （11） （12） In the formula, f 1 represents operating costs; f 2 represents carbon emissions; For maintenance costs; For the first i Fuel consumption cost of one diesel generator; For the first i Pollutant emissions from a diesel generator; Ng This represents the total number of diesel generators in the DC integrated power system. For ship fuel costs; , , For the first i Generator parameters; and Representing the first i diesel generator t Constant output power and rated power; For the operating costs of energy storage systems; Cost of converting thermal energy to electrical energy; for t The heat absorbed by thermal energy storage at all times; for t The heat released by the thermal energy storage at all times; for t The power consumed by the electrothermal conversion device at all times; The carbon dioxide conversion coefficient; , , For the first i Carbon emission parameters of a diesel generator.

5. The method for calculating the economic dispatch of ships in a DC integrated power system according to claim 4, characterized in that, The constraints of the DC integrated power system for waste heat recovery from the hydrogen fuel cell are specifically expressed as follows: （13） （14） （15） （16） （17） （18） （19） （20） （21） In the formula, Power of the electrothermal conversion device; Power required for residential load; The power required for electric propulsion loads; The heat is output to the electrothermal conversion device; It generates heat for hydrogen fuel cells; This represents the total heat of the system. For the first i Minimum output power of a diesel generator; For the first i The rated power of the diesel generator; This refers to the climbing power of the diesel generator; For energy storage system capacity; / This represents the minimum / maximum change in indoor temperature. for t Real-time indoor temperature; / This represents the minimum / maximum indoor temperature. This represents the allowable distance error between intermediate ports; This represents the allowable distance error between the initial port and the destination port. It is the distance between ports; This represents the total voyage distance between the initial port and the final port. This represents the actual distance the ship travels between the two ports. for t Ship speed at any given time.

6. The method for calculating the economic dispatch of ships in a DC integrated power system according to claim 5, characterized in that, The optimization algorithm obtains the optimal variable combination. Specifically, it uses a multi-objective particle swarm optimization algorithm to solve the economic scheduling of ships in a DC integrated power system. First, variables are initialized to form a population P with N particles. Then, within the constraints of the DC integrated power system with hydrogen fuel cell waste heat recovery, a speed is randomly assigned to each particle. Second, each particle is evaluated based on the economic scheduling objective function of the DC integrated power system based on fuel cell waste heat recovery. Then, it is checked whether the operating cost and pollutant emissions of the DC integrated power system ships are minimized. If not, the particles are updated using speed and position update formulas, generating a new population Q. Subsequently, populations P and Q are integrated to synthesize a new population R, and population R is sorted. After sorting, N optimal particles are reselected for the next iteration. Finally, the final optimized scheduling result is output until the program ends.

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