Control method of full-submersible multifunctional offshore energy island system and energy island system

Abstract

The present application relates to the technical field of deep-sea ocean engineering, and provides a control method of a full-submersible multifunctional offshore energy island system and the energy island system, comprising: in response to a typhoon warning instruction, acquiring sea state parameters in a future time period, and establishing a relationship between a wave spectrum and the sea state parameters; through a wave attenuation theory, establishing wave energy attenuation coefficients at different shelter depths; according to a structural dynamics model of a full-submersible support structure, establishing water-comprehensive-platform motion response amplitude operators under different shelter depths and different wave frequencies; based on the relationship between the wave spectrum and the sea state parameters, the wave energy attenuation coefficients and the water-comprehensive-platform motion response amplitude operators, solving an optimal shelter depth within a water-comprehensive-platform motion safety threshold; and based on the optimal shelter depth, adjusting a ballast water tank water injection amount, so as to submerge the full-submersible support structure to the optimal shelter depth. The problem of "over-submergence" or "under-submergence" caused by a fixed depth is avoided.

Description

Technical Field

[0001] This invention belongs to the field of deep-sea marine engineering technology, and particularly relates to the control method and energy island system of a fully submersible multifunctional marine energy island system. Background Technology

[0002] The statements in this section are merely background information related to the present invention and do not necessarily constitute prior art.

[0003] As the global energy transition accelerates, the development of renewable energy sources such as offshore wind power is gradually moving towards the deep sea. However, the deep sea environment is characterized by complex wind, wave, and current conditions, frequent extreme weather events, and long distances from the shore, posing severe challenges to the construction and operation of offshore platforms.

[0004] Existing offshore platform technologies have the following limitations: It is difficult to balance wind and wave resistance with the convenience of personnel living: Traditional semi-submersible / barge platforms concentrate power generation, energy storage and living functions on the surface deck. The structure is simple but the wind and wave resistance is limited. In extreme sea conditions such as typhoons and giant waves, the platform's movement response is violent, personnel need to be evacuated, and the long-term living comfort is poor. Single function and lack of coordination: Most existing deep-sea platforms are single-function (such as independent wind farms and oil and gas platforms), lacking comprehensive bases that integrate energy production, energy storage and regulation, personnel accommodation, material storage and wind farm maintenance. As a result, wind farm maintenance has to start from distant shore bases, which is slow to respond and costly. Offshore wind power operation and maintenance response time is long: Deep-sea wind farms are usually more than 100 kilometers away from shore-based maintenance bases, and maintenance vessels need several hours to travel one way, resulting in serious delays in fault response; personnel commuting costs are high: maintenance personnel are at sea for long periods of time, which is greatly limited by weather windows, resulting in short effective working time, and there are also safety hazards such as seasickness and fatigue; lack of intermediate supply bases: Deep-sea areas lack transit stations where maintenance vessels can dock, personnel can rest, and supplies can be replenished, which seriously restricts the economics of wind farms.

[0005] More importantly, existing offshore platform control systems are designed only for single operating conditions and do not incorporate multi-objective collaborative optimization based on the wave propagation attenuation laws in deep-sea areas and the platform's structural dynamics. They cannot dynamically adapt to the wind-sheltered diving depth according to real-time sea conditions, making it difficult to balance the core requirements of wave resistance safety, operational energy consumption, and operational efficiency. At the same time, existing technologies lack dynamic power control strategies for multi-energy coupled systems, resulting in poor coordination and matching between energy production, energy storage, and load power consumption. This further reduces the overall operational efficiency of the integrated energy island and fails to meet the industrial application requirements of routine operation and maintenance, all-weather safe operation, and efficient energy supply for deep-sea wind farms. Summary of the Invention

[0006] To address the technical problems mentioned above, this invention provides a control method and energy island system for a fully submersible multifunctional marine energy island system, featuring adaptive wind shelter depth adjustment: through wave attenuation theory, platform motion response model, and multi-objective optimization, the optimal wind shelter depth is dynamically calculated to minimize the diving depth while ensuring platform safety, thereby reducing ballast energy consumption and ascent recovery time, and avoiding the "over-diving" or "under-diving" problems caused by a fixed depth.

[0007] To achieve the above objectives, the present invention adopts the following technical solution: The first aspect of the present invention provides a control method for a fully submersible multi-functional marine energy island system, comprising: In response to typhoon warning instructions, obtain sea state parameters for the future time period and establish the relationship between wave spectrum and sea state parameters; Based on wave attenuation theory, wave energy attenuation coefficients at different sheltered depths are established. Based on the structural dynamics model of the fully submersible support structure, an amplitude operator for the motion response of the integrated water platform under different sheltered depths and wave frequencies is established. Based on the relationship between wave spectrum and sea state parameters, wave energy attenuation coefficient and motion response amplitude operator of integrated water platform, the optimal shelter depth is solved within the motion safety threshold of integrated water platform. Based on the optimal shelter depth, the water injection volume of the ballast water tank is adjusted to allow the fully submersible support structure to submerge to the optimal shelter depth.

[0008] Furthermore, the sea state parameters include: significant wave height, spectral peak period, and main wave direction.

[0009] Furthermore, the wave energy attenuation coefficient is α(z) = e -kz Where k is the wave number, k = 2π / λ, and λ is the wavelength, which is related to the wave period T. p Satisfying λ=(gT) p ²) / (2π), where g is the acceleration due to gravity.

[0010] Furthermore, the motion safety thresholds for the integrated water platform include a pitch angle threshold and a heave amplitude threshold.

[0011] Furthermore, the inequality satisfied by the optimal shelter depth is: ; Where S(ω) is the wave spectrum, The wave energy attenuation coefficient. R is the amplitude operator for the motion response of the integrated water platform. max The safety threshold for the movement of the water-based integrated platform.

[0012] Furthermore, it also includes: using a rolling time-domain optimization algorithm to solve for the optimal power allocation within the future time window in each control cycle, with the goal of minimizing system operating costs or maximizing renewable energy utilization.

[0013] Furthermore, it also includes: using the optimal power allocation as the power reference value, and performing real-time power adjustment based on the bus voltage deviation.

[0014] A second aspect of the present invention provides a fully submersible multifunctional marine energy island system, comprising a fully submersible support structure, a surface integrated platform, and an intelligent control system integrated on the surface integrated platform. Ballast water tanks are arranged inside the fully submersible support structure, and the intelligent control system is equipped with a control method for the fully submersible multifunctional marine energy island system as described in the first aspect.

[0015] Furthermore, the top of the fully submersible support structure is provided with several fixed connecting columns, the lower end of which is fixedly connected to the top of the fully submersible support structure and the upper end of which is fixedly connected to the bottom of the water-based integrated platform.

[0016] Furthermore, the aforementioned integrated water platform adopts a deck structure and is divided into functional areas: a living area, an energy storage area, a material storage area, and a power generation operation area.

[0017] Compared with the prior art, the beneficial effects of the present invention are: This invention features adaptive wind shelter depth adjustment: by using wave attenuation theory, platform motion response model and multi-objective optimization, the optimal wind shelter depth is dynamically calculated. Under the premise of ensuring platform safety, the diving depth is minimized, ballast energy consumption and ascent recovery time are reduced, and the problems of "over-diving" or "under-diving" caused by fixed depth are avoided. Attached Figure Description

[0018] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0019] Figure 1 This is a flowchart of the control method for the fully submersible multi-functional marine energy island system according to Embodiment 1 of the present invention; Figure 2 This is a schematic diagram of the functional zoning layout of the integrated water platform according to Embodiment 1 of the present invention; Figure 3 This is a schematic diagram of the layout of the ballast water tanks and underwater energy equipment inside the fully submersible support structure according to Embodiment 1 of the present invention; Figure 4 This is a block diagram of the energy flow direction in Embodiment 1 of the present invention; Figure 5 This is a flowchart of the adaptive windbreak depth determination method according to Embodiment 2 of the present invention. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings.

[0021] It should be noted that the following detailed description is illustrative and intended to provide further explanation of the invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0022] Example 1 This embodiment provides a fully submersible, multi-functional offshore energy island system.

[0023] The fully submersible multi-functional marine energy island system provided in this embodiment, such as Figure 1 As shown, it includes a fully submersible support structure 1, connecting columns 21, a surface integrated platform 3, and integrated functional modules and intelligent control systems integrated on the surface integrated platform 3.

[0024] like Figure 3 As shown, the fully submersible support structure 1 is a cylindrical pressure hull 11, which is permanently submerged below the water surface (normal operating depth is 10-30 meters below the water surface), and is mainly responsible for providing buoyancy and ensuring stability of the system.

[0025] like Figure 3 As shown, the interior of the fully submersible support structure 1 mainly houses ballast water tanks 12 (for depth adjustment) and underwater energy harvesting equipment 13 (e.g., tidal power generator sets, watertight compartments, with the power generation section extending outside the shell).

[0026] like Figure 3 As shown, a small number of emergency refuge cabins 14 can be set up inside the fully submersible support structure 1 as needed, for personnel to take temporary refuge in extreme situations, but not as the main living area.

[0027] like Figure 3 As shown, the top of the fully submersible support structure 1 is provided with mounting bases 15 for multiple fixed connecting columns 21.

[0028] like Figure 1 As shown, the top of the fully submersible support structure 1 is provided with several fixed connecting columns 21. The lower end of the connecting columns 21 is fixedly connected to the top of the fully submersible support structure 1, and the upper end is fixedly connected to the bottom of the water-based integrated platform 3.

[0029] The connecting column 21 mainly serves as a structural support. It can be equipped with pipeline channels (for laying cables, water pipes, and communication optical cables) to connect the upper and lower parts. It does not provide a daily passage for personnel (personnel activities are concentrated on the water platform).

[0030] The connecting column 21 is made of high-strength corrosion-resistant material, and the connection with the fully submersible support structure 1 is reinforced.

[0031] The third integrated water platform will be permanently above the water, serving as the main place for personnel to live, work, store, and generate electricity.

[0032] The 3rd integrated water platform adopts a large deck structure, such as Figure 2 As shown, the area is divided according to functional zones: Living Area 31: Includes living quarters, dining hall, medical room, recreation room, and control center; equipped with a complete living system (ventilation, heating, and fresh water supply); Energy storage area 32: Centrally located energy storage battery cabinet 321, hydrogen storage tank 322 (if hydrogen energy is used), and fuel generator (backup); in addition, a seawater desalination unit 323 is installed to provide fresh water for the living area; Material storage area 33: includes spare parts warehouse, food warehouse, tool room, and cold storage; Power generation operation area 34: Installation of wind turbine generator sets 341, photovoltaic panel arrays 342, helicopter landing pads 343, ship berthing docks 344, and meteorological monitoring equipment 345.

[0033] The water-based integrated platform 3 is equipped with safety railings 35, life-saving equipment, and a fire-fighting system.

[0034] The intelligent control system is located in the control center of the surface integrated platform 3, which integrates and monitors the operation status of the entire fully submersible multi-functional marine energy island system.

[0035] The integrated functional modules of this embodiment include: Energy Module: The main power generation sources for the surface integrated platform 3 are wind and solar power; the tidal energy of the fully submersible support structure 1 provides supplementary power generation; the energy storage area 32 on the surface integrated platform 3 enables time-shift regulation of electrical energy, such as... Figure 4 As shown; Living support module: living area + seawater desalination + sewage treatment + food storage to meet the living needs of permanent residents; in addition, it can be combined with aquaculture to achieve a stable food supply. Operation and maintenance support module: material warehouse + maintenance tool room + ship berthing facilities + helicopter pad, providing maintenance support for surrounding wind farms; Positioning and navigation module: The surface integrated platform 3 is equipped with a satellite positioning system (BeiDou / GPS); the fully submersible support structure 1 is equipped with an underwater acoustic positioning system to provide a positioning reference for underwater vehicles.

[0036] The operating mode switching of the fully submersible multi-functional marine energy island system provided in this embodiment is as follows: Normal operating mode: The fully submersible support structure 1 is maintained at the normal operating depth H1 (e.g., 15 meters below the water surface); the floating integrated platform 3 generates electricity normally, personnel live in the living area 31, and provide berthing and resupply to the maintenance vessels of the surrounding wind farms via the ship berthing dock 344; the tidal power generator unit continuously generates electricity to supplement the platform's power consumption.

[0037] Typhoon Shelter Survival Mode: Upon receiving a typhoon warning, all personnel are evacuated back to the mainland or transferred to the emergency refuge chamber 14 within the fully submersible support structure 1; ballast tank 12 is filled with water, and the fully submersible support structure 1 submerges to a shelter depth H2 (e.g., 50 meters below the water surface); the surface integrated platform 3 subsequently sinks a certain distance but remains above the water surface; the wind turbine generator 341 on the surface integrated platform 3 is shut down and feathered, and all doors and windows are closed and reinforced; the surface integrated platform 3 relies on the tidal power generator and the reserve power in the energy storage area 32 to maintain basic operation (e.g., navigation lights, communication equipment); the fully submersible support structure 1 is deeply submerged, significantly reducing the platform's movement amplitude with the waves and ensuring structural safety.

[0038] Recovery mode: After the typhoon, ballast tank 12 is drained, the fully submersible support structure 1 floats to the normal operating depth H1, personnel return to the platform, and operations resume.

[0039] The fully submersible multi-functional marine energy island system provided in this embodiment has centralized functions and is easy to operate: living quarters, energy storage, and materials are all located on the water platform, and personnel do not need to frequently dive up and down for daily activities, thus improving living comfort and operational efficiency.

[0040] The fully submersible multi-functional marine energy island system provided in this embodiment has a simplified underwater structure: the fully submersible support structure is only responsible for buoyancy, ballast and underwater energy harvesting, and does not require a complex life support system inside, resulting in a simple structure and high reliability.

[0041] The fully submersible multi-functional offshore energy island system provided in this embodiment is multi-energy complementary and has a stable power supply: surface wind power and photovoltaic power + underwater tidal energy + platform energy storage, to achieve stable power supply around the clock.

[0042] The fully submersible multi-functional marine energy island system provided in this embodiment includes a deep-sea maintenance hub: the underwater acoustic positioning system of the underwater support structure can provide navigation for surrounding underwater vehicles; and the materials and berths on the surface platform can provide support for surface maintenance vessels.

[0043] Example 2 The control method for the fully submersible multifunctional marine energy island system provided in this embodiment is configured within the intelligent control system of the fully submersible multifunctional marine energy island system described in Embodiment 1, and includes: Step 1: In response to the typhoon warning, based on sea state forecast data and the platform's dynamic response model, dynamically calculate the optimal shelter depth H2, such as... Figure 5 As shown.

[0044] Step A1: Obtain sea state parameters for the future time period through the meteorological forecasting system, including significant wave height H. s Spectral peak period T p The main direction of the wave is θ.

[0045] Step A2: Based on wave attenuation theory, establish the wave energy attenuation coefficient α(z) = e at different shelter depths z. -kz Where k is the wave number, k = 2π / λ, and λ is the wavelength, which is related to the wave period T. p Satisfying λ=(gT) p ²) / (2π), where g is the acceleration due to gravity.

[0046] Step A3: Based on the structural dynamics model of the fully submersible support structure, establish the motion response amplitude operator RAO(z,ω) of the waterborne integrated platform under different shelter depths z and different wave frequencies ω.

[0047] Specifically, the response amplitude operator is essentially the motion response amplitude of a floating body under the action of a regular wave with a unit amplitude at a specific frequency (ω) and direction (z). RAO(z,ω) is a transfer function, mathematically defined as the ratio of the motion response (X(ω)) of a specific degree of freedom to the wave amplitude (F(ω)): RAO(ω) = X(ω) / F(ω).

[0048] To calculate the transfer function RAO(z,ω), the core is to solve the frequency domain motion equation of the floating body in the waves. For a system with N floating bodies, the general matrix form of the equation is as follows: [-ω²(M+A(ω))+iωB(ω)+(C_h+C_m)]·X(ω)=F_w(ω); Where ω is the angular frequency of the wave; M is the structural mass / inertia matrix of the floating body; A(ω) is the added mass matrix, representing the inertial effect of the surrounding fluid when the floating body accelerates; B(ω) is the potential flow damping matrix, representing the energy lost by the floating body due to the radiation waves generated during its motion; C_h is the still water restoring force stiffness matrix, representing the buoyancy / gravity effect that returns the floating body to its equilibrium position; C_m is the external stiffness matrix (such as the stiffness of mooring cables and connectors); X(ω) is the complex motion response amplitude of the floating body (i.e., the quantity to be solved); F_w(ω) is the complex amplitude of the wave excitation force (moment). The entire [-ω²(M+A(ω))+iωB(ω)+(C_h+C_m)] on the left side of the equation is called the impedance matrix. By solving the above equation, the complex form of the motion response X(ω) can be obtained, and RAO (amplitude) is the magnitude (absolute value) of this complex response.

[0049] RAO(ω) = |X(ω)| / |F_w(ω)| (when the amplitude is unit 1, |F_w(ω)| = 1), where the amplitude of RAO represents the magnitude of the response; the phase angle of X(ω) represents the phase difference of the response relative to the excitation wave.

[0050] The influence of depth z in RAO(z,ω) is not directly reflected in the above equations, but rather indirectly through changes in the hydrodynamic coefficients (A(ω), B(ω)) and wave excitation force (F(ω)). Specifically, changing depth z alters the submerged shape of the float, thus affecting: Added mass A(ω) and radiation damping B(ω): The change in the wetted surface shape of the float alters the volume of water displaced and the wave field generated during motion, thereby affecting these two parameters. Wave excitation force F(ω): The wave pressure distribution acting on the wetted surface of the float varies with its submerged depth. Therefore, to establish RAO(z,ω), it is necessary to recalculate the hydrodynamic coefficients (A,B) and wave force (F) of the float at each depth of interest z, and then substitute them into the frequency domain motion equations for solution.

[0051] Step A4: Establish the relationship between the wave spectrum S(ω) and sea state parameters, wherein the wave spectrum S(ω) is described by the JONSWAP spectrum or PM spectrum to describe the distribution of wave energy in the frequency domain.

[0052] Specifically, S(ω)=αg 2 / ω 5 .exp[ β(ω0 / ω) 4 ]; Where: ω: wave angular frequency (rad / s), typically ranging from 0.2 to 3.0 rad / s; g: gravitational acceleration, taken as 9.81 m / s²; α = 8.1 × 10⁻⁶ 3 (Dimensionless constant, Phillips constant); β = 0.74 (dimensionalless constant); ω0 = g / U 19.5 U 19.5 The wind speed (m / s) is located at a height of 19.5m above the sea surface. The wind speed U is obtained through a meteorological forecasting system. 19.5 Substituting the values ​​into the formula will generate the complete spectral curve.

[0053] Step A5: Set the motion safety threshold R for the integrated water platform max Including the pitch angle threshold θ max , heave amplitude threshold η max Find the minimum depth z that satisfies the following inequality. : ; Among them, z This is the optimal shelter depth H2. Optimal shelter depth z The minimum depth required to simultaneously satisfy safety constraints for heave and pitch motion.

[0054] Step A6: The intelligent ballast control system automatically adjusts the water injection volume of the ballast tank according to the calculated H2, so that the fully submersible support structure can be submerged to that depth.

[0055] For example, obtaining weather forecast data: significant wave height H s =12m, spectral peak period T p =14s, the wave direction makes an angle of 30° with the main axis of the platform; Calculate wavelength λ=λ=(gT) p 2) / (2π)≈306m, wavenumber k==2π / λ≈0.0205; The wave spectrum S(ω) is established and described using JONSWAP spectrum; By combining the platform motion response amplitude operator RAO(z,ω), the root mean square value of the platform motion response at different depths z is calculated; Set safety thresholds: pitch angle ≤ 5°, heave amplitude ≤ 1m; Find the minimum depth z that satisfies the safety conditions. The calculation result is H2=42m; Ballast tank 12 is filled with water, and support structure 1 is submerged to a depth of 42 meters instead of a fixed depth, which saves ballast energy consumption and reduces the ascent recovery time by about 20%.

[0056] Step 2: Based on predictive control and hierarchical optimization architecture, achieve optimized energy allocation across multiple time scales.

[0057] Step 201, Upper-level scheduling layer: Step B1: Using meteorological forecast data, establish prediction curves for wind speed and light intensity within a future time window T (e.g., 24 hours).

[0058] Step B2: Based on historical electricity consumption data and operation and maintenance plans, predict the load demand curve within the future time window T.

[0059] Step B3: Define the optimization objective function to minimize system operating costs and maximize renewable energy utilization. Let t be the current time, T be the optimization time window length (e.g., 24 hours), and τ be the integration time variable (τ∈[t,t+T]). Let C... bat The battery charge / discharge cost coefficient (yuan / kWh) reflects the battery cycle life loss and charge / discharge efficiency loss; P bat (τ) represents the charging and discharging power of the battery energy storage system at time τ, with positive values ​​indicating charging (consuming electrical energy) and negative values ​​indicating discharging (releasing electrical energy); Ch2 The hydrogen production cost coefficient (yuan / kWh) includes the comprehensive costs of electrolyzer power consumption, seawater desalination, and compressor energy consumption; P elec (τ) represents the hydrogen production power consumed by the electrolyzer at time τ; C curt P is the power curtailment penalty factor (yuan / kWh); curt (τ) represents the abandoned power at time τ (the power of renewable energy generation that is discarded due to lack of utilization). The following multi-objective optimization function is established: ; Among them, the power curtailment penalty coefficient C curt The value of satisfies C curt C bat C h2 This allows the system to prioritize the use of renewable energy, and only permits power curtailment when both energy storage and hydrogen energy systems have reached their capacity limits.

[0060] The power balance constraint is: P wind (τ)+P pv (τ)+P tidal (τ)+P fc (τ)+P bat_dis (τ)=P load (τ)+P bat_ch (τ)+P elec (τ)+P curt (τ); Among them, P elec (τ) represents the hydrogen production power of the electrolyzer; P wind (τ), P pv (τ), P tidal (τ) represents the output power of wind power, photovoltaic power, and tidal current power generation at time τ, respectively; P fc (τ) represents the output power of the hydrogen fuel cell at time τ; P load (τ) represents the total system load at time τ (including residential electricity consumption, maintenance equipment, seawater desalination, etc.); P bat_ch (τ) and P bat_dis (τ) represents the battery charging power and discharging power (P) respectively. bat (τ)=P bat_ch (τ) P bat_dis (τ), and only one mode works at any given time.

[0061] Through the above optimizations, the system prioritizes the consumption of all renewable energy generation when the energy storage and hydrogen energy capacities allow, and only generates curtailment when both the energy storage and hydrogen energy systems reach their capacity limits, thereby maximizing the utilization rate of renewable energy.

[0062] Step B4: Use the rolling time-domain optimization algorithm (model predictive control, MPC) to solve for the optimal power allocation within the future time window T in each control cycle Δt, and issue and execute the instructions for the first control cycle. Then, update the prediction data on a rolling basis and repeat the optimization.

[0063] Step 202, Lower Real-Time Layer: Step C1: Monitor the bus voltage Udc and system frequency fac in real time, using seconds / minutes as the time scale.

[0064] Step C2: P in the optimal power allocation output by the upper scheduling layer bat0 P fc0 As the power reference value for the lower real-time layer, a droop control model for the battery energy storage system and the hydrogen fuel cell system is established: P bat =P bat0 +k bat (Udc Uref); P fc =P fc0 +k fc (Udc Uref); Where, k bat k fc The droop coefficient is... Uref is the measured voltage, and P is the reference voltage. bat0 P represents the power reference value of the battery energy storage system. fc0 This represents the power reference value for a hydrogen fuel cell system. Based on the droop control model, calculate the power command; determine the power direction, P bat >0 Battery charging (absorbing power, causing voltage drop), P fc =>0 Fuel cell generates electricity (outputs power, causing voltage to rise).

[0065] Step C3: The lower layer adjusts the power in real time according to the bus voltage deviation to achieve instantaneous power balance.

[0066] Step C3 adjusts the output power of each distributed power source, specifically including: Battery energy storage system: Adjusting its charging and discharging power Pbat; Hydrogen fuel cell system: Adjusting its power generation Pfc.

[0067] When the system power is unbalanced, the bus voltage will deviate from the reference value. Droop control responds to the voltage deviation by adjusting the power of these devices in real time, thus restoring the bus voltage to stability.

[0068] Step C4: The upper and lower layers achieve coordination through state variable interaction. The upper layer coordinates based on the battery state of charge (SOC) and hydrogen storage pressure (P). h2 The real-time feedback is used to adjust the scheduling plan.

[0069] Specifically, when the upper scheduling layer performs rolling optimization in each control cycle (e.g., every 15 minutes), it first obtains the battery state of charge (SOC) from the lower real-time layer. measured (t) and hydrogen storage pressure P h2_measured The measured value of (t) is used as the initial state of the optimization model: SOC(0) = SOC measured (t),P h2 (0)=P h2_measured (t); Where t is the current time, SOC(0) and P h2 (0) represents the initial values ​​of the battery state of charge and the initial value of the hydrogen storage pressure at the start of the optimization time window, respectively.

[0070] In the optimization model, SOC and P h2 The kinetic equations are as follows: ; ; Where Δt is the discrete time step, E bat P is the rated total capacity of the battery. bat (k) represents the battery charging and discharging power (positive value for discharging, negative value for charging); R is the ideal gas constant, T is the temperature inside the hydrogen storage tank, V is the effective volume of the hydrogen storage tank, and η elec For the hydrogen production efficiency of the electrolyzer, P elec (k) represents the power consumed by the electrolyzer for hydrogen production, P fc (k) represents the fuel cell output power, η fc This refers to the power generation efficiency of fuel cells.

[0071] At the same time, SOC and P h2 As a constraint, it participates in the optimization: SOC min ≤SOC(k)≤SOC max ; P h2_min ≤P h2 (k)≤P h2_max ; Among them, SOC min SOC max These are the lower and upper limits of the allowable state of charge of the battery, respectively, P. h2_min P h2_max These represent the lower and upper limits of the permissible hydrogen storage pressure, respectively.

[0072] When the State of Charge (SOC) approaches its upper limit, the upper layer automatically limits the battery charging power and prioritizes allocating excess power to the electrolyzer for hydrogen production; when the SOC approaches its lower limit, the upper layer automatically limits the battery discharging power and prioritizes power supply from the fuel cell. Similarly, when P... h2 When approaching the upper limit, the upper layer reduces the electrolyzer power and can increase the fuel cell output; when P h2 When the limit is approached, the upper layer prioritizes hydrogen production from the electrolyzer and limits power generation from the fuel cell.

[0073] Through the aforementioned feedback correction mechanism, the upper-level scheduling layer can dynamically adjust the power allocation strategy according to the real-time status of the energy storage system, thereby achieving coordinated optimization of the battery and hydrogen energy system, avoiding overcharging and over-discharging of the battery and empty / over-pressure of the hydrogen storage tank, and improving the safety and economy of system operation.

[0074] The control method for the fully submersible multi-functional marine energy island system provided in this embodiment features adaptive wind shelter depth adjustment: by using wave attenuation theory, platform motion response model and multi-objective optimization, the optimal wind shelter depth is dynamically calculated, minimizing the diving depth while ensuring platform safety, reducing ballast energy consumption and ascent recovery time, and avoiding the "over-diving" or "under-diving" problems caused by fixed depth.

[0075] The control method for the fully submersible multifunctional offshore energy island system provided in this embodiment features multi-source collaborative energy optimization management: it adopts an energy management strategy that combines predictive control and hierarchical optimization. The upper-level scheduling layer performs rolling time-domain optimization based on power generation and load forecasts, while the lower-level real-time layer achieves instantaneous power balance based on droop control. This approach balances long-term economic efficiency and real-time stability, improves the renewable energy absorption rate, and extends the lifespan of energy storage equipment.

[0076] It should be noted that each module in this embodiment corresponds one-to-one with each step in Embodiment 1, and their specific implementation processes are the same, so they will not be repeated here.

[0077] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A control method for a fully submersible multi-functional offshore energy island system, characterized in that, include: In response to typhoon warning instructions, obtain sea state parameters for the future time period and establish the relationship between wave spectrum and sea state parameters; Based on wave attenuation theory, wave energy attenuation coefficients at different sheltered depths are established. Based on the structural dynamics model of the fully submersible support structure, an amplitude operator for the motion response of the integrated water platform under different sheltered depths and wave frequencies is established. Based on the relationship between wave spectrum and sea state parameters, wave energy attenuation coefficient and motion response amplitude operator of integrated water platform, the optimal shelter depth is solved within the motion safety threshold of integrated water platform. Based on the optimal shelter depth, the water injection volume of the ballast water tank is adjusted to allow the fully submersible support structure to submerge to the optimal shelter depth.

2. The control method for the fully submersible multi-functional marine energy island system as described in claim 1, characterized in that, The sea state parameters include: significant wave height, spectral peak period, and main wave direction.

3. The control method for the fully submersible multifunctional marine energy island system as described in claim 1, characterized in that, The wave energy attenuation coefficient is α(z) = e -kz Where k is the wave number, k = 2π / λ, and λ is the wavelength, which is related to the wave period T. p Satisfying λ=(gT) p ²) / (2π), where g is the acceleration due to gravity.

4. The control method for the fully submersible multi-functional marine energy island system as described in claim 1, characterized in that, The motion safety thresholds for the integrated water platform include the pitch angle threshold and the heave amplitude threshold.

5. The control method for the fully submersible multifunctional marine energy island system as described in claim 1, characterized in that, The inequality satisfied by the optimal shelter depth is: ； Where S(ω) is the wave spectrum, The wave energy attenuation coefficient. R is the amplitude operator for the motion response of the integrated water platform. max The safety threshold for movement of the water-based integrated platform.

6. The control method for the fully submersible multifunctional marine energy island system as described in claim 1, characterized in that, It also includes: using a rolling time-domain optimization algorithm to solve for the optimal power allocation within a future time window in each control cycle, with the goal of minimizing system operating costs or maximizing renewable energy utilization.

7. The control method for the fully submersible multi-functional marine energy island system as described in claim 6, characterized in that, Also includes: Using the optimal power allocation as the power reference value, real-time power adjustment is performed based on the bus voltage deviation.

8. The control system of a fully submersible multi-functional marine energy island system, characterized in that: The system includes a fully submersible support structure, a surface integrated platform, and an intelligent control system integrated on the surface integrated platform. The fully submersible support structure is equipped with ballast water tanks, and the intelligent control system is equipped with a control method for a fully submersible multi-functional marine energy island system as described in any one of claims 1-7.

9. The control system of the fully submersible multifunctional marine energy island system as described in claim 8, characterized in that, The top of the fully submersible support structure is provided with several fixed connecting columns. The lower end of the connecting columns is fixedly connected to the top of the fully submersible support structure, and the upper end is fixedly connected to the bottom of the water-based integrated platform.

10. The control system of the fully submersible multifunctional marine energy island system as described in claim 8, characterized in that, The above-ground integrated platform adopts a deck structure and is divided into functional areas: living area, energy storage area, material storage area and power generation operation area.

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