Multi-time scale scheduling method for port multi-region integrated energy system

Abstract

The invention relates to the technical field of scheduling of energy systems, in particular to a multi-time-scale scheduling method for a port multi-region integrated energy system, and the method comprises the steps: collecting operation data of energy equipment, carrying out the fusion processing, and generating source load prediction data; and constructing a multi-time-scale scheduling model including day-ahead scheduling, intra-day scheduling and real-time scheduling based on the prediction data. A long-term operation plan is made through day-ahead scheduling to optimize the system operation cost; in-day scheduling, energy equipment operation parameters are adjusted based on a short-time-interval rolling optimization strategy, and prediction errors are corrected; real-time scheduling is combined with a flexible direct current device and an energy storage unit to dynamically optimize power distribution, and supply and demand balance of an energy system is maintained. Through multi-time-scale cooperative regulation and control, the operation cost is reduced, the new energy utilization efficiency and the system economy are improved, and the method is suitable for port integrated energy system scheduling optimization in a complex load environment.

Description

Technical Field

[0001] The present invention relates to the technical field of scheduling of energy systems, and in particular to a multi-time scale scheduling method for a multi-region integrated energy system of a port. Background Art

[0002] In the existing technology, the scheduling of energy systems in port areas usually adopts a single time scale or static optimization method, which fails to effectively address the following problems: Renewable energy sources such as wind power and photovoltaics have large fluctuations, which, combined with the randomness of port load demand, lead to unstable system operation; traditional scheduling methods ignore the response characteristics and adjustment capabilities of different energy equipment (such as energy storage units and electrolyzers), making it difficult to achieve a dynamic balance between supply and demand; existing technologies mostly rely on long-term load forecasts, whose errors accumulate over time, making it difficult to correct deviations in scheduling plans in a timely manner. These shortcomings make it difficult for existing solutions to balance energy efficiency and economy, further restricting the development of multi-regional integrated energy systems in ports. Summary of the invention

[0003] In view of the many problems existing in the above-mentioned prior art, the present invention provides a multi-time scale scheduling method for a multi-region integrated energy system in a port. The present invention coordinates the operation of controllable energy resources in the port by constructing a three-level multi-time scale scheduling model, combining long-term planning of day-ahead scheduling, short-term optimization of intraday scheduling, and dynamic adjustment of real-time scheduling. Through the coordinated regulation of flexible DC devices and energy storage equipment, system power balance is achieved, while the utilization efficiency of new energy is improved and the system operation cost is reduced.

[0004] A multi-time scale scheduling method for a multi-region integrated energy system of a port comprises the following steps: Collecting the operating data of various energy equipment in the port integrated energy system, including power load data, renewable energy generation data and equipment operating status data; fusing the operating data to generate predicted source-load data within a time range for building a multi-time scale scheduling model; Based on the predicted source-load data, a multi-time-scale scheduling model including day-ahead scheduling, intraday scheduling and real-time scheduling is constructed: day-ahead scheduling is used to formulate an operation plan for the port integrated energy system in the future to optimize the system operation cost; intraday scheduling is based on the day-ahead scheduling plan and more accurate prediction data to dynamically adjust the operating parameters of energy equipment to cope with source-load prediction deviations and changes in operating status; real-time scheduling is based on real-time source-load data to dynamically optimize the energy supply and demand balance in the system by coordinating the operation of energy equipment and power distribution devices; Coordinate the operation of energy equipment and power transmission devices, and maintain the operation of the port area energy system through the synergy of energy storage units, fuel cells and flexible DC devices; According to the operating results of the multi-time scale scheduling model, the scheduling parameters are continuously adjusted to achieve energy supply and demand optimization.

[0005] Preferably, the operating data is acquired through distributed data acquisition nodes deployed in the port area. Each acquisition node is connected to the corresponding energy equipment and is used to collect real-time data on the operating status, power load and renewable energy generation of the energy equipment, and generate predicted source-load data containing time series through data fusion model processing.

[0006] Preferably, the data fusion model is based on a time series analysis algorithm, combining historical operation data of port equipment with electricity purchase records of external power networks, to predict power load demand and renewable energy generation capacity within the next 24 hours, and generate predicted source-load data.

[0007] Preferably, the day-ahead scheduling generates an operation plan for energy equipment through an optimization algorithm, wherein the operation plan includes the start and stop status of the electrolyzer, the working power of the electrolyzer, the charging power and discharging power of the energy storage unit, and the power transfer amount of the flexible DC device, and the optimization goal is to reduce the system operating cost and meet the energy balance constraints of the port area.

[0008] Preferably, the optimization algorithm for the day-ahead scheduling uses a time interval of 15 minutes, considers the startup time of the equipment, the maximum power output and the fluctuation characteristics of renewable energy power generation, allocates the load demand in different areas of the port area and generates a step-by-step operation plan.

[0009] Preferably, the intraday scheduling is based on a rolling optimization strategy, with updated predicted source-load data as input, and combined with the operation plan generated by the day-ahead scheduling, the charging power, discharging power of the energy storage unit and the power output of the fuel cell are dynamically adjusted. The optimization goal of the dynamic adjustment is to reduce the impact of source-load fluctuations on the operation of the port area energy system.

[0010] Preferably, the rolling optimization strategy performs calculations every 5 minutes, monitors the charge state of the energy storage unit based on real-time updated random source load forecast data, and dynamically corrects equipment operating parameters to ensure safe operation and continuous power supply capability of the energy equipment.

[0011] Preferably, the real-time scheduling is based on the power load data of the first bus and the second bus collected in real time, adjusts the power distribution through the bidirectional power transmission function of the flexible DC device, and realizes the real-time load balance of the port energy system in combination with the charging and discharging behavior of the energy storage unit.

[0012] Preferably, the flexible DC device calculates the power transfer amount according to the voltage difference between the first bus and the second bus, and when excess power is detected, it preferentially transmits power to the low-load bus, and reduces the external power purchase amount in combination with real-time regulation of the energy storage unit.

[0013] Preferably, the charge state of the energy storage device is optimized by adjusting the charging rate of the energy storage unit and the power generation power of the fuel cell to prevent overcharging or over-discharging, and the dynamic balance of energy supply and demand in the port area is ensured by coordinating the operation of the energy storage unit and the flexible DC device.

[0014] Compared with the prior art, the advantages and beneficial effects of the present invention are: By constructing a multi-time scale scheduling model, the effect of dynamically adjusting the operating parameters of energy equipment is achieved: day-ahead scheduling is used to formulate long-term operation plans and optimize the working status of energy equipment; intraday scheduling adopts a rolling optimization strategy to adjust operating parameters at short time intervals and correct prediction errors; real-time scheduling combines flexible DC devices and energy storage units to coordinately optimize power distribution and maintain system supply and demand balance.

[0015] Accurate source-load prediction is achieved through distributed data collection and fusion technology: prediction data is generated based on real-time collection and historical analysis, providing high-precision input for the scheduling model.

[0016] By optimizing the coordinated operation of energy storage and hydrogen energy equipment, the effect of improving the utilization rate of new energy is achieved: dynamically regulating the charging and discharging behavior of energy storage equipment and the hydrogen production rate of the electrolyzer, reducing energy waste and lowering electricity purchase costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a schematic diagram of the multi-region integrated energy system of the port in the present invention; Figure 2 It is a schematic diagram of the multi-time scale scheduling framework of the port integrated energy system in the present invention; Figure 3 This is a schematic diagram of the core concept of intra-day rolling scheduling in the present invention; Figure 4 This is the bus energy balance diagram of section I dispatched in the present invention a day ago; Figure 5 This is the bus power balance diagram for the day-ahead dispatching of section II in the present invention; Figure 6 This is a rendering of the day-ahead dispatching energy storage system in the present invention; Figure 7 This is the hydrogen energy balance diagram for day-ahead scheduling in the present invention; Figure 8 This is the bus power balance diagram for intra-day dispatching of section I in the present invention; Fig. 9 This is the bus power balance diagram for the intra-day dispatching of Section II in the present invention; Fig.10 This is a rendering of the intra-day dispatching energy storage system in the present invention; Fig.11It is the intra-day scheduling hydrogen energy balance diagram of the present invention; Fig.12 It is a schematic diagram of real-time simulation results in the present invention; Fig.13 It is a schematic diagram for comparing simulation results in the present invention; Fig.14 It is a schematic diagram of the process of the present invention. DETAILED DESCRIPTION

[0018] Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings. However, it should be understood that these descriptions are exemplary only and are not intended to limit the scope of the present disclosure. In the following detailed description, for ease of explanation, many specific details are set forth to provide a comprehensive understanding of the embodiments of the present disclosure. However, it is obvious that one or more embodiments may also be implemented without these specific details. In addition, in the following description, descriptions of known structures and technologies are omitted to avoid unnecessary confusion of the concepts of the present disclosure.

[0019] The terms used herein are only for describing specific embodiments and are not intended to limit the present disclosure. The terms "include", "comprising", etc. used herein indicate the existence of the features, steps, operations and / or components, but do not exclude the existence or addition of one or more other features, steps, operations or components.

[0020] All terms (including technical and scientific terms) used herein have the meanings commonly understood by those skilled in the art unless otherwise defined. It should be noted that the terms used herein should be interpreted as having a meaning consistent with the context of this specification and should not be interpreted in an idealized or overly rigid manner.

[0021] The present invention aims to realize the efficient utilization of energy in ports and the sustainable development of ports, and designs a multi-time scale optimization scheduling method for multi-regional integrated energy systems in ports. The execution steps are as follows: Fig.14 As shown in Figure 1. The port integrated energy system can integrate external power grid, renewable energy devices, power equipment, chemical energy storage units and soft openpoint (SOP) devices. Renewable energy devices include wind power generation systems and solar photovoltaic systems. Power equipment includes container bridge cranes, shore cranes, ship shore power systems and lighting facilities. Figure 1 As shown in the figure, the framework design of the multi-energy fusion system is proposed. In Substation No. 6, a flexible DC device connecting two buses is installed. The function of this device is to adjust the energy balance between the two buses, and the flexible DC converter is a new device in the power grid.

[0022] Taking into account that there are certain errors in load forecasting and renewable energy output forecasting, the prediction accuracy increases with the shorter the time scale and the closer to the current moment. In addition, the adjustment rates of various adjustable resources are different. Some resources respond to adjustment instructions slowly, such as alkaline electrolyzer equipment, etc., which require a long time in advance to formulate an operation plan, while some resources respond to adjustment instructions quickly, such as electrochemical energy storage, etc., which can formulate adjustment plans in a shorter time and act in time to fill the deviation of the adjustment effect caused by factors such as prediction errors and equipment abnormalities. Therefore, it is necessary to revise the optimization scheduling scheme based on multi-time scale source-load prediction results. Based on this, the present invention constructs a multi-energy coordinated optimization scheduling architecture for the port area, and decomposes the optimization scheduling of the port area multi-energy fusion system into three different time scales: day-ahead planning, intraday rolling scheduling, and real-time scheduling, so as to coordinate adjustable resources with different adjustment rates and eliminate the influence of prediction errors and system interference step by step.

[0023] The multi-time scale scheduling optimization scheduling architecture of the multi-region integrated energy system of the port is as follows Figure 2 As shown in the figure, it is divided into three different time scales: day-ahead planning, intraday rolling scheduling and real-time scheduling. The scheduling resources and optimization models of each time scale have different focuses.

[0024] from Figure 2 It can be seen that the strategy is based on day-ahead dispatch, and gradually improves the dispatch plan through intraday rolling optimization to achieve more accurate dispatch results. Finally, according to the real-time source and load data, the SOP and the power of the No. 2 energy storage are adjusted to achieve bus power balance. In the day-ahead optimization dispatch stage, a plan is made every 24 hours, and each time a plan for the next 24 hours is made, with a time scale of 15 minutes. The day-ahead dispatch aims to minimize the total operating cost of the system, and uses the forecast data of renewable energy output and load demand to formulate the output plan of each unit in the system for the next 24 hours. However, since a single day-ahead optimization dispatch may be significantly different from the actual situation, it is necessary to further adjust the output plan through intraday optimization dispatch to improve feasibility.

[0025] The day-ahead dispatching gives priority to the electrolytic cell equipment with the worst flexibility and determines the following operating parameters: the start and stop status identification position of the water electrolysis equipment; and the operating power of the water electrolysis equipment.

[0026] In the intraday optimization scheduling stage, a plan is made every 5 minutes, and each time a plan for the next 2 hours is made, with a time scale of 5 minutes. In intraday scheduling, due to the randomness of the fluctuation of renewable energy power generation, it is required to continuously revise the unit output plan determined by the day-ahead scheduling during the adjustment process to ensure that the day-ahead scheduling plan can be carried out efficiently. The core idea of ​​intraday rolling scheduling can be summarized as follows: exist t time, with t arrive t+2Random source load forecast information within the hour, equipment operating parameters that have been determined a few days ago, and t The equipment operating parameters determined before the time are used as input variables and brought into the model to find t arrive t+2 The best scheduling solution within the hour interval, but only The scheduling results within the interval are used for system scheduling. Repeat the above rolling scheduling idea until all scheduling of 288 moments in a day is completed.

[0027] The day-ahead scheduling model is as follows: Energy purchase cost , system operation and maintenance costs and carbon emission costs composition:

[0028] The energy purchase cost includes the electricity purchase cost and the hydrogen purchase cost:

[0029] Where: , and They are the electricity purchase price, electricity sales price and hydrogen purchase price; and are the purchased power and sold power at time t respectively; is the hydrogen purchase rate at time t.

[0030] The operation and maintenance costs of each device in the port integrated energy system are as follows:

[0031] Where: is the start-up and shutdown cost of the electrolyzer; and They are the unit operating costs of wind turbines, photovoltaics, soft opening points, energy storage, electrolyzers, fuel cells and hydrogen storage tanks; is the number of fans; It is Typhoon in t Power at the moment; Photovoltaic equipment in t The power generation at the moment; for t The SOP power of bus section I and bus section II at the moment stipulates that the power transferred from bus section I to bus section II is positive; They are t The charging power and discharging power of the energy storage device at all times; fort The operating power of the electrolyzer at any moment; for t The operating power of the fuel cell at all times; for t The hydrogen storage rate of the hydrogen storage tank at this moment. A value greater than 0 indicates hydrogen storage, and a value less than 0 indicates hydrogen release.

[0032] Carbon emission costs are indirectly generated by the system purchasing electricity from the external power grid:

[0033] Where: Unit CO 2 Emission costs, For CO 2 Emission factors.

[0034] The constraints are as follows: Restrictions on electricity purchase and sale:

[0035]

[0036] Where: and They are the upper limits of the power purchased and the power sold respectively.

[0037] External hydrogen purchase constraints:

[0038] Where: is the upper limit of hydrogen purchase rate.

[0039] The state of charge (SOC) of an energy storage device indicates the charge or energy level of the energy storage element and is used to describe the degree of its charging or discharging. t At this moment, the SOC of the energy storage device can be obtained by the following formula:

[0040] Where: for t The charge status of the energy storage device at all times; is the total capacity of the energy storage device; It is the remaining capacity of the energy storage device at the last moment; are the charging / discharging efficiency of the energy storage device, respectively.

[0041] In order to ensure that the energy storage system operates in the optimal state and prevent overcharging or over-discharging, a certain margin must be reserved for the capacity of the energy storage system. Therefore, it is necessary to properly control the state of charge of the energy storage device:

[0042] Where: , They represent the upper and lower limits of the state of charge of the energy storage device respectively.

[0043] To ensure that the energy storage system can be used normally in the next dispatch, its initial and final power levels need to remain consistent:

[0044] Where: is the state of charge of the energy storage device at the end of the scheduling time, It is the charge state of the energy storage device at the initial scheduling time.

[0045] The charging and discharging power of the energy storage system needs to be kept within a certain range:

[0046]

[0047] Where: is a 0-1 variable, Indicates that the energy storage device is in charging state, otherwise ; Indicates that the energy storage device is in a discharging state. Otherwise . and They are the upper limits of the charging power and discharging power of the energy storage system respectively.

[0048] Energy storage system t Cannot be in charging and discharging state at the same time:

[0049] Since the SOP characteristic has power limitations, its operating constraints are:

[0050] Where: It is the upper limit of flexible DC transfer power.

[0051] An electrolyzer is an electrochemical device that uses electricity to decompose water into hydrogen and oxygen. Due to its characteristics, the electrolyzer has power-on and power-off constraints and ramp-up constraints. With shutdown action , the operating state of the electrolytic cell before and after the difference can be obtained to obtain the combined sequence of power on and off actions .from t The stop state of time 0 to t The running state 1 at time +1 is called the power-on action, and its state flag is equal to -1. t The running status at time 1 to t +1 time stop state 0 is called shutdown action, and its status flag is equal to 1. t Moment and t +1 If the state is always stopped or running, no power on / off action occurs, and the state flag is equal to 0.

[0052]

[0053] In order to calculate the start-up costs of the electrolyzers and shutdown costs , it is necessary to further combine the electrolytic cell power on and off action sequence Decoupling.

[0054]

[0055] Turn the electrolytic cell on and off After decoupling, they can be multiplied by the unit startup cost and unit shutdown cost , after accumulation, the total cost of switching on and off in a certain period of time can be obtained .

[0056]

[0057] In addition, the operating power of the electrolyzer needs to be kept within a certain range.

[0058]

[0059] Where: is the lower limit of electrolytic cell power, is the electrolyzer power rating.

[0060] t Hydrogen production power by water electrolysis at any time The hydrogen production rate of the electrolyzer The relationship between (kg / h) is as follows:

[0061]

[0062] Where: is the hydrogen production coefficient of the electrolyzer, kg / kWh; is the Faraday efficiency, which reflects the ratio of actual hydrogen production to theoretical hydrogen production and is closely related to the electrolysis temperature; is the number of electrolyzers in the electrolyzer array, is the number of moles of electrons transferred in the reaction of hydrogen; is the Faraday constant, which is approximately 96485 coulombs per mole ( ); A constant terminal voltage maintained for the AC / DC converter.

[0063] The ramp power constraint of the electrolyzer is:

[0064] Where: It is the maximum climbing power per unit time period when the electrolyzer is in the on state.

[0065] Hydrogen fuel cells use hydrogen energy to generate electricity. They are a green and environmentally friendly high-quality power source. The reaction of proton exchange membrane fuel cells can be regarded as the reverse process of water electrolysis. The output voltage is generated by the accumulation of mobile charges during the reaction, and a large amount of heat is released along with the reaction. The relationship between high-purity hydrogen energy and output power is as follows:

[0066] Where: for t The rate at which the fuel cell uses hydrogen at a given moment; is Avogadro's constant; is the molar mass of hydrogen; is the number of electrons per coulomb; for t Rated output voltage at all times; is the fuel cell conversion efficiency.

[0067] Fuel cells also need to meet power constraints:

[0068] Where: and They are the upper and lower limits of the fuel cell operating power respectively.

[0069] The capacity of the hydrogen energy storage system is determined by the amount of gas stored in the hydrogen storage tank. In order to reflect the hydrogen storage situation of the hydrogen storage tank and facilitate energy management, the equivalent state of charge of the hydrogen storage tank is:

[0070] Where: is the maximum capacity of the hydrogen storage tank; It is the mass of hydrogen stored in the hydrogen storage tank at the last moment.

[0071] In order to ensure that the hydrogen storage tank is in the best working condition and avoid overcharging and overdischarging, the capacity of the hydrogen storage tank needs to have a certain margin. The equivalent state of charge constraints of the hydrogen storage tank are:

[0072] Where: and They are respectively the upper and lower limits of the equivalent state of charge of the hydrogen storage tank.

[0073] The hydrogen inlet and outlet rates of the hydrogen storage tank need to be kept within a certain range:

[0074] Where: The maximum rate at which a hydrogen storage tank can store and release hydrogen.

[0075] To ensure that the hydrogen storage tank can be used normally in the next dispatch, its hydrogen storage level needs to be consistent from beginning to end:

[0076] Where: is the charge state of the hydrogen storage tank at the end of scheduling time, It is the charge state of the hydrogen storage tank at the initial scheduling time.

[0077] Due to the involvement of flexible DC equipment, it is necessary to ensure that the energy supply and load demand on bus section I and bus section II are balanced at any time. The power balance relationship is as follows:

[0078]

[0079] Where: , , and For busbar section I and busbar section II t The power purchase and sales at any given moment; and for t The electrical load power of bus section I and bus section II at this moment.

[0080] Due to the presence of hydrogen-powered equipment in the port area (such as hydrogen-powered container trucks and hydrogen-powered forklifts), hydrogen energy needs to be balanced at any time. The hydrogen energy balance relationship is as follows:

[0081] Where: for t Hydrogen consumption rate at the time, kg / h.

[0082] The goal of the intraday scheduling rolling optimization model is consistent with the day-ahead scheduling, but the parameters that need to be re-forecasted for intraday scheduling include wind power generation, solar power generation, power load of bus section I and bus section II, and hydrogen load. Although the day-ahead scheduling has planned the output of all units 24 hours in advance, the accuracy of such advance predictions is usually low. Therefore, intraday scheduling shortens the prediction time to 2 hours and reduces the time interval to 5 minutes to obtain more accurate prediction results. Based on these more accurate predictions, a more reasonable intraday scheduling plan can be formulated to optimize the economic scheduling plan for the day-ahead.

[0083] The core purpose of intraday dispatch is to deal with the deviation of random source load forecast from the day-ahead to the day-ahead. By adjusting the output of each device, the output of other controllable devices is further refined based on the equipment operating parameters determined by the day-ahead dispatch. Therefore, intraday dispatch can use the same objective function as the day-ahead dispatch, but due to the use of random source load forecasts with smaller errors, its dispatch results will be more accurate.

[0084] The objective function is as follows:

[0085] Constraints: The constraints for intraday scheduling mainly include three parts: single equipment operation constraints, energy balance constraints, and coupling constraints between day-ahead and intraday.

[0086] Among them, the single equipment operation constraints (Formula 5-26) and energy balance constraints (Formula 27-29) are consistent with the day-ahead scheduling.

[0087] The day-ahead and intra-day coupling constraints include the operating power and start / stop status of the electrolyzer.

[0088]

[0089]

[0090] Where: is the day-ahead dispatch result of the electrolyzer operating power, It is the day-ahead scheduling result of the start and stop status of the electrolyzer.

[0091] Due to the different time scales between day-ahead scheduling and intraday scheduling, the ramp power constraint of the electrolyzer changes to:

[0092] Where: It is the maximum climbing power per unit time period when the electrolyzer is in the on state.

[0093] In the real-time dispatching stage, when the system detects a power imbalance between the two bus sections, the system will immediately start the control strategy to achieve fast and effective regulation. SOP can transfer the remaining power on a certain bus section to another bus section, which can not only reduce the system's electricity purchase cost, but also reduce the waste of renewable energy and realize the energy transmission between the two ends of the bus. At the same time, the No. 2 energy storage system, as a flexible regulation resource, can play an important role in the power system. When there is excess power, the energy storage system can absorb excess power, and when there is insufficient power, it can release the stored power to balance supply and demand. The collaborative work of SOP and No. 2 energy storage can achieve precise control of power imbalance. It can not only maintain the stable operation of the power grid, but also optimize resource allocation, reduce energy waste, and ultimately achieve the goal of reducing system operating costs.

[0094] is the net load power of bus section I, is the net load power of bus section II, Provides power to SOP.

[0095] when When , the SOP transfer power flows from bus section I to bus section II; when When , the SOP transfers power from bus section II to bus section I.

[0096] The power flows from the low load bus to the high load bus. If the load rate of bus section I is greater than that of bus section II, the SOP transfer power needs to flow from bus section II to bus section I, and the power command is a negative value, otherwise the power command is a positive value. The adjusted bus power is = + , = . is the charging and discharging power of energy storage No. 2, When it is in charging state, It is in the discharging state.

[0097] According to the load conditions of bus section I and bus section II, it can be divided into 4 state machines. They are as follows: State Machine 1: ,

[0098] State Machine 2:

[0099] State Machine 3:

[0100] State Machine 4: ,

[0101] State Machine 1 ( ) and This indicates that the new energy output of the port power system is consumed locally and there is still a power shortage.

[0102] State machine 1 is mainly for the case where the net loads of bus section I and bus section II in the port area are both greater than 0. First, it is necessary to determine whether the No. 2 energy storage has the ability to charge and discharge. or , then SOP and No. 2 energy storage will not be dispatched and need to purchase electricity from the external power grid. , further judgment is needed If true, it means that the No. 2 energy storage and SOP cannot meet the load requirements of the two bus sections. At this time, the No. 2 energy storage discharges at the maximum discharge power. , further judge If true, it means that the No. 2 energy storage can only provide power for the II section bus, and no excess power is transferred to the I section bus. If not, it means that the energy released by the No. 2 energy storage can still be transferred to the I section bus through SOP after meeting the load demand of the II section bus. .like This is not true, indicating that the No. 2 energy storage and SOP can fully meet the load requirements of bus section I and bus section II. , .

[0103] State Machine 2 ( ) and , indicating that there is load demand on bus section I and surplus power on bus section II.

[0104] State machine 2 is mainly for the case where the net load of section I bus in the port area is greater than 0 and the net load of section II bus is less than 0. First, determine Is it true? If it is true, it means that the net load of bus section I exceeds the SOP transfer upper limit and enters the left process. If this is true, it means that the remaining power of bus section II also exceeds the SOP transfer upper limit. At this time, the excess power of bus section II needs to be transferred to bus section I according to the SOP maximum transfer upper limit. Next, we need to determine whether the SOC of energy storage No. 2 has reached the upper and lower limits. If so, it will not charge. If not, it is necessary to determine whether the remaining power after the II section bus is turned on exceeds the maximum charging power of the maximum No. 2 energy storage. If so, charge at the maximum charging power. If not, charge according to the remaining power of bus section II. .like This means that the excess power of bus section II does not exceed the SOP transfer upper limit. It is necessary to further determine the SOC state of energy storage No. 2. If energy storage No. 2 cannot be charged or discharged, then , and the excess power of bus section II needs to be transferred to bus section I. If the No. 2 energy storage can be charged and discharged, then it is necessary to determine If true, it means that the sum of the remaining power of bus section II and the power that can be released by energy storage No. 2 does not exceed the maximum transfer limit of SOP. At this time, No. 2 operates at the maximum discharge power. , SOP transfers the remaining power of bus section II and the energy released by energy storage No. 2 to bus section I, If not, it means that the busbar in section II has a lot of residual energy, and the energy storage No. 2 can reach the upper limit of SOP transfer without discharging at maximum power. , .

[0105] like If it is not true, it means that the net load of bus section I is less than the upper limit of SOP transfer, and then enter the right process. First, determine whether the load demand of bus section I is greater than the remaining power of bus section II. If so, further determine whether energy storage 2 is available. If so, further determine whether the sum of the remaining power of bus section II and the discharge of energy storage 2 is greater than the load demand of bus section I. If so, then , If not, it means that the No. 2 energy storage needs to operate at the maximum discharge power. , If the No. 2 energy storage is unavailable, then , SOP transfers the remaining power of bus section II to bus section I, If the load demand of bus section I is less than the remaining power of bus section II, the power required by bus section I is directly transferred from bus section II to bus section I through SOP. Next, it is necessary to determine whether energy storage No. 2 is available. If so, it is necessary to determine whether the power of bus section II after transfer is less than the maximum discharge power of energy storage No. 2. If so, energy storage No. 2 is charged at the maximum charging rate. If not established, , if the No. 2 energy storage is unavailable, then .

[0106] State Machine 3 ( ) and , indicating that there is load demand on bus section II and surplus power on bus section I.

[0107] State machine 3 is mainly for the case where the net load of bus section I in the port area is less than 0 and the net load of bus section II is greater than 0. First, determine whether the load demand of bus section II exceeds the SOP transfer upper limit. If so, enter the left process. Determine whether the remaining power of bus section I exceeds the SOP transfer upper limit. If so, then , bus section I still has surplus energy and needs to sell energy to the external grid, and then determine whether energy storage No. 2 is available. If energy storage No. 2 is not available, then If the No. 2 energy storage is available, it is further determined whether the net load of the II section bus after receiving the electric energy transferred by the SOP is greater than the maximum released electric energy of the No. 2 energy storage. If so, it means that the No. 2 energy storage and SOP cannot fully meet the load demand of the II section bus, and it is still necessary to purchase electricity from the external power grid. The No. 2 energy storage discharges at the maximum power. , if not, then If the remaining power of bus section I does not exceed the upper limit of SOP transfer, it is necessary to transfer all the remaining power of bus section I to bus section II, and then further determine whether energy storage No. 2 is available. If not, no charging and discharging operations will be performed. If available, it is also determined whether the net load of bus section II after receiving the SOP transferred power is greater than the maximum released power of energy storage No. 2. If so, , if not, then .

[0108] If the load demand of bus section II does not exceed the SOP transfer upper limit, enter the right process. Determine whether the remaining power of bus section I is greater than that of bus section II. If so, further determine whether the remaining power of bus section I exceeds the SOP transfer upper limit. If so, it is necessary to determine whether energy storage No. 2 is available. If so, determine + , if established, then , ,like + If not established, , If the No. 2 energy storage is unavailable, the bus section I will only transfer the net load power of the bus section II to the bus section II. If the remaining energy of bus section I does not exceed the SOP transfer upper limit, it is necessary to further determine whether energy storage No. 2 is available. If it is available, further determine + Is it true? If so, all the remaining power of bus section I will be transferred to bus section II. On the basis of meeting the load demand of bus section II, the remaining electricity is used to charge energy storage No. 2. If not, then , If the No. 2 energy storage is unavailable, then , If the remaining power of bus section I is less than that of bus section II, it is necessary to transfer all the remaining power of bus section I to bus section II, and then further determine whether energy storage No. 2 is available. If it is available, determine If true, it means that the No. 2 energy storage needs to discharge at maximum power. If not, then , if the No. 2 energy storage is unavailable, then .

[0109] State Machine 4 ( ) and , indicating that there is surplus electric energy in both bus section I and bus section II.

[0110] State machine 4 is mainly for the case where the net loads of bus section I and bus section II in the port area are both less than 0. First, it is necessary to determine whether the remaining power of bus section II is less than the maximum discharge power of energy storage No. 2. If so, it means that there is no need to transfer electric energy from bus section I to bus section II. , determine whether energy storage No. 2 is available. If it is available, energy storage No. 2 is charged at the maximum charging rate. , if not available, then If the remaining power of bus section II is greater than the maximum discharge power of energy storage No. 2, further judgment is required. If it is established, then it is necessary to transfer all the remaining power of bus section I to bus section II to further determine whether energy storage II is available. If it is available, then , if not available, then .like If not established, , further determine whether the No. 2 energy storage is available. If available, then , if not available, then .

[0111] Result analysis: Using the present invention to conduct simulation analysis, the total cost of the day-ahead scheduling stage is 116,849.75 yuan, and the total cost of intraday scheduling is 112,095.16 yuan. Compared with day-ahead scheduling, the total cost of intraday scheduling is reduced by 4,754.59 yuan, about 4.07%.

[0112] The simulation results of day-ahead scheduling are as follows: Figure 4 It can be seen that from 0 to 5 o'clock, the bus load level is low and the wind power generation level is high. The load demand can be basically met by relying on wind turbine power generation, flexible direct current transfer power and energy storage system discharge. As time goes by, the power generation of photovoltaics gradually increases, which reflects the important role of renewable energy in the power grid, especially during the daytime, the output of solar photovoltaics is significant. When the level of new energy power generation is high, in order to meet the hydrogen load demand in the port area, alkaline electrolyzers are used to electrolyze water to produce hydrogen. It can be seen that at a certain point in time, the total output of wind power and photovoltaics exceeds the load demand. At this time, the power grid balances the excess electricity through energy storage charging, flexible direct current transfer or electricity sales. After 12 o'clock, the output of wind power and photovoltaics began to decline, and the load level increased, resulting in an increase in electricity purchases. This may be to ensure that the power grid can meet the load demand when the output of renewable energy is insufficient.

[0113] from Figure 5 It can be clearly seen that the load fluctuates during this period, which may be due to the characteristics of port operations. In the initial stage, the load is relatively low. At this time, wind power generation becomes the main source of electricity. The excess electricity is transferred to the I section bus through flexible direct current to meet the basic needs of the power grid. This shows that wind power plays an increasingly important role in renewable energy, especially in areas with rich wind energy resources. It is worth noting that fuel cells also play an important role during this period. Although the rated power of the fuel cell is low, only 280kW, it still shows the potential and application value of fuel cells in the power grid as a clean and efficient energy conversion technology. As time goes by, the power generation of wind power begins to decrease gradually, and the purchase of electricity begins to appear, which shows that during this period, the II section bus cannot meet its own power demand and needs to purchase electricity from the external power grid.

[0114] Figure 6The relationship between the charging power, discharging power and the state of energy storage (SOC) of the energy storage system over a certain period of time is shown. The energy storage system undergoes multiple charge and discharge cycles during this period. The charging power and discharging power vary from -2500kW to 2500kW, which indicates that the energy storage system stores and releases energy according to the grid demand in different periods. In the initial stage, the energy storage system starts charging with a higher charging power, which may be due to low grid demand or high renewable energy generation, so there is excess electricity to store. As time goes by, the charging power gradually decreases until it approaches 0, which may mean that the energy storage system is close to a full charge state (SOC is close to the maximum value of 0.85). During the charging process, the SOC of the energy storage system gradually increases from 0.2 to 0.8, which indicates that the effective capacity of the energy storage system is fully utilized. After the SOC reaches a high level, the energy storage system begins to switch to the discharge mode to meet the peak demand of the grid or fill the intermittency of renewable energy generation. The increase in discharge power indicates that the energy storage system begins to release the stored energy to support the stable operation of the grid. As the discharge progresses, the SOC gradually decreases, which reflects the energy consumption of the energy storage system. During the discharge process, the SOC of the energy storage system dropped from 0.8 to 0.3, which shows that during this period, the energy storage system effectively supported the load demand of the power grid. It is worth noting that during the discharge process, the peak of the discharge power reached 2500kW, which may correspond to the peak period of power grid demand. This shows that the energy storage system helps to balance the fluctuations of supply and demand in the power grid and improve the reliability and stability of the power grid.

[0115] from Figure 7 It can be seen that in the initial stage, the hydrogen production matches the hydrogen load, which indicates that the system is able to meet part of the demand by producing hydrogen through water electrolysis. Over time, the hydrogen production fluctuates, which may be related to the operating status of the electrolyzer. In the subsequent stage, when the hydrogen production cannot meet the demand, the system supplements it by purchasing additional hydrogen, and the fluctuation of the purchased hydrogen is closely related to the change of hydrogen load. This strategy helps to ensure the stability of hydrogen supply, especially when the hydrogen production capacity is limited or the demand surges. The fluctuation of hydrogen storage reflects the storage and release of hydrogen by the system in different time periods. The increase and decrease of hydrogen storage is coordinated with the changes in hydrogen load, hydrogen production and hydrogen purchase to ensure the continuity and reliability of hydrogen supply. The SOH of the hydrogen storage tank is an important indicator to measure the status of the hydrogen storage tank. The SOH fluctuates between 0.2 and 0.8, which indicates that the hydrogen storage tank stores different amounts of hydrogen in different time periods.

[0116] The day-ahead dispatch has determined the operating parameters of the unit with the worst flexibility. The intraday dispatch stage needs to continue to use such day-ahead dispatch results and focus on determining the variable values ​​of the energy storage system charging and discharging power, fuel cell output, and hydrogen storage tank hydrogen storage rate. Since the intraday predicted random source load is closer to the real value, the intraday dispatch based on the intraday predicted random source load curve is more in line with actual needs. The intraday dispatch simulation results are shown in Figure 2. Figure 8-Figure 11 shown.

[0117] Whether it is intraday scheduling or day-ahead scheduling, the core goal is to ensure the balance of supply and demand in the power system, optimize resource allocation, and improve the efficiency and reliability of system operation. Wind power and photovoltaics, as renewable energy sources, are fully utilized in both scheduling strategies. The energy storage system plays a role in regulating supply and demand and balancing load fluctuations in both scheduling strategies. Especially in intraday scheduling, the charging and discharging behavior of the energy storage system is more frequent to cope with the rapid changes in intraday load. The operating power and start-stop status of the electrolyzers scheduled intraday have not changed, but the power of other equipment has all changed further with the fluctuations of the new random source-load curve. From Figure 8-Figure 11 It can be seen that the results of intraday scheduling are more volatile, which reflects the instability of intraday load and renewable energy generation.

[0118] Through comparative analysis of intraday scheduling and day-ahead scheduling result graphs, it can be concluded that although the two have similarities in scheduling objectives and scheduling elements, there are significant differences in time scale, data granularity, flexibility of scheduling strategies, prediction accuracy and volatility of scheduling results.

[0119] In the real-time scheduling stage, 5 minutes of real-time source and load data are selected for simulation. The simulation results are as follows: from Fig.12It can be seen that the No. 2 energy storage system exhibits an extremely high frequency of charging and discharging in the real-time dispatching stage, frequently reaching the upper limit of its charging and discharging power. This high-frequency and high-depth charging and discharging behavior of the No. 2 energy storage system has a significant positive impact on maintaining the supply and demand balance of the power grid. It helps to relieve the pressure on the power grid and reduce the fluctuation of power supply by discharging at peak power demand and charging at low power demand, which reflects its high efficiency and flexibility in real-time dispatching. Despite the frequent charging and discharging activities, the SOC value of the No. 2 energy storage system does not change much, which shows that it can effectively manage energy storage in real-time dispatching, avoid excessive charging and discharging, and ensure the long-term health and performance of the energy storage system. SOP also plays an important role in the real-time dispatching stage. Especially when the output of renewable energy does not match the load, resulting in power shortage and power surplus in the two sections of the bus, SOP transfers the surplus power of one section of the bus to the other section of the bus with power shortage. On the one hand, it can achieve power balance of the two ends of the bus and reduce the purchase of electricity from the external power grid. On the other hand, it can further play the advantages of charging and discharging of No. 2 energy storage and improve the utilization rate of renewable energy. The power fluctuation amplitude of bus section I before and after optimization is reduced, and the optimized power shows smoother fluctuations, which indicates that the optimization strategy effectively reduces the power fluctuation of bus section I and improves the stability of power supply. Similarly, the power fluctuation of bus section II also shows a decreasing trend after optimization, and the optimized power curve is close to zero in some periods, which means that during these periods, the power supply and demand have reached a better balance and the dependence on external power resources has been reduced. The optimized power curve is more stable than that of bus section I. This is because the No. 2 energy storage of bus section II discharges at peak power demand and charges at low power demand, ensuring the power stability of bus section II. The optimization effect of total bus power is more obvious. The optimized power curve shows smaller fluctuations most of the time, which indicates that the load fluctuation of the entire power system has been effectively controlled.

[0120] from Fig.13 It can be seen that the cost of purchasing and selling electricity for the bus before adjustment was 132.55 yuan, and the cost of purchasing and selling electricity for the bus after adjustment was 83.60 yuan, a decrease of about 36.93%. The carbon emission cost of the bus before adjustment was 11.24 yuan, and the carbon emission cost of the bus after adjustment was 6.97 yuan, a decrease of about 37.99%. The SOP operation and maintenance cost after adjustment was 0.63 yuan, and the operation and maintenance cost of the No. 2 energy storage after adjustment was 0.99 yuan.

[0121] Beneficial effects: By introducing a multi-time scale optimization model, efficient scheduling of the multi-regional integrated energy system of the port is achieved, effectively improving the energy utilization efficiency and the economy of system operation. In the simulation analysis, the total cost is reduced by about 4.07% compared with the traditional scheduling method through the two-stage scheduling strategy of day-ahead and day-intraday, reducing the operating cost of the system. Through the real-time scheduling strategy, the cost of purchasing electricity is reduced by 36.93% and the carbon emission cost is reduced by 37.99%. At the same time, the potential of renewable energy such as wind and solar energy is fully tapped, and through flexible scheduling strategies, the proportion of new energy in the energy structure is increased, which promotes the effective use of renewable energy.

[0122] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems or computer program products. Therefore, the present application may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware.

[0123] The above are only embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the scope of the claims of the present application.

Claims

1. A multi-time scale scheduling method for a multi-region integrated energy system of a port, characterized in that: The following steps are involved: Collecting the operating data of various energy equipment in the port integrated energy system, the operating data includes power load data, renewable energy generation data and equipment operating status data; fusing the operating data to generate predicted source-load data within a time range for building a multi-time scale scheduling model; Based on the predicted source-load data, a multi-time-scale scheduling model including day-ahead scheduling, intraday scheduling and real-time scheduling is constructed: day-ahead scheduling is used to formulate an operation plan for the port integrated energy system in the future to optimize the system operation cost; intraday scheduling is based on the day-ahead scheduling plan and more accurate prediction data to dynamically adjust the operating parameters of energy equipment to cope with source-load prediction deviations and changes in operating status; real-time scheduling is based on real-time source-load data to dynamically optimize the energy supply and demand balance in the system by coordinating the operation of energy equipment and power distribution devices; Coordinate the operation of energy equipment and power transmission devices, and maintain the operation of the port area energy system through the synergy of energy storage units, fuel cells and flexible DC devices; According to the operating results of the multi-time scale scheduling model, the scheduling parameters are continuously adjusted to achieve energy supply and demand optimization.

2. The multi-time scale scheduling method for a multi-region integrated energy system of a port according to claim 1 is characterized in that: The operating data is obtained through distributed data collection nodes deployed in the port area. Each collection node is connected to the corresponding energy equipment to collect real-time data on the operating status of the energy equipment, power load and renewable energy generation, and generate predicted source-load data containing time series through data fusion model processing.

3. The multi-time scale scheduling method for a multi-region integrated energy system of a port according to claim 2 is characterized in that: The data fusion model is based on a time series analysis algorithm, combining the historical operation data of port equipment with the electricity purchase records of the external power network to predict the power load demand and renewable energy generation capacity in the next 24 hours and generate predicted source-load data.

4. The multi-time scale scheduling method for a multi-region integrated energy system of a port according to claim 1, characterized in that: The day-ahead scheduling generates an operation plan for energy equipment through an optimization algorithm. The operation plan includes the start and stop status of the electrolyzer, the working power of the electrolyzer, the charging power and discharging power of the energy storage unit, and the power transfer amount of the flexible DC device. The optimization goal is to reduce the system operating cost and meet the energy balance constraints of the port area.

5. The multi-time scale scheduling method for a multi-region integrated energy system of a port according to claim 4 is characterized in that: The optimization algorithm for day-ahead scheduling takes 15-minute time intervals into account, the startup time of the equipment, the maximum power output, and the fluctuation characteristics of renewable energy generation, allocates the load demand in different areas of the port area, and generates a step-by-step operation plan.

6. The multi-time scale scheduling method for a multi-region integrated energy system of a port according to claim 1, characterized in that: The intraday scheduling is based on a rolling optimization strategy, with updated predicted source-load data as input, and combined with the operation plan generated by the day-ahead scheduling, to dynamically adjust the charging power, discharging power of the energy storage unit and the power output of the fuel cell. The optimization goal of the dynamic adjustment is to reduce the impact of source-load fluctuations on the operation of the port area energy system.

7. The multi-time scale scheduling method for a multi-region integrated energy system of a port according to claim 6, characterized in that: The rolling optimization strategy performs calculations every 5 minutes, monitors the charge state of the energy storage unit based on the real-time updated random source load forecast data, and dynamically corrects the equipment operating parameters to ensure the safe operation and continuous power supply capability of the energy equipment.

8. The multi-time scale scheduling method for a multi-region integrated energy system of a port according to claim 1, characterized in that: The real-time scheduling is based on the real-time collected power load data of the first bus and the second bus, adjusts the power distribution through the bidirectional power transmission function of the flexible DC device, and combines the charging and discharging behavior of the energy storage unit to achieve real-time load balancing of the port energy system.

9. The multi-time scale scheduling method for a multi-region integrated energy system of a port according to claim 8, characterized in that: The flexible DC device calculates the power transfer amount according to the voltage difference between the first bus and the second bus. When excess power is detected, power is transmitted to the low-load bus first, and the external power purchase amount is reduced in combination with the real-time regulation of the energy storage unit.

10. The multi-time scale scheduling method for a multi-region integrated energy system of a port according to claim 1, characterized in that: By adjusting the charging rate of the energy storage unit and the power generation power of the fuel cell, the charge state of the energy storage equipment is optimized to prevent overcharging or over-discharging. By coordinating the operation of the energy storage unit and the flexible DC device, the dynamic balance of energy supply and demand in the port area is ensured.

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