Electrochemical energy storage-water-wind-light multi-time-scale nested complementary scheduling method

Abstract

The invention discloses an electrochemical energy storage-water-wind-light multi-time-scale nested complementary scheduling method. The method comprises the steps that a day-ahead water-wind-light complementary scheduling model with the maximum daily power generation benefit as the target is established; constructing an intra-day water-wind-light complementary scheduling model with the goal of minimizing the sum of power generation water consumption of the whole hydropower station and penalty water consumption of unit start-stop and vibration region crossing, so as to reduce the risk of frequent start-stop of the unit; establishing a real-time electrochemical energy storage-water-wind-light multi-energy complementary optimization scheduling model with a minimum comprehensive flexibility value as a target, and reducing the risk of lacking and abandoning electricity of a complementary system and the risk of self-scheduling of water and electricity; through day-ahead-day-real-time multi-time-scale nested scheduling and step-by-step information feedback, flexible adjustment requirements of different time scales are met, and cooperative scheduling operation of a hydropower station and electrochemical energy storage is guided. According to the method, the scheduling requirements of the multi-energy complementary system under different time scales can be met, and the hydropower scheduling risk is reduced while the wind and light absorption level and the system power supply reliability are improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of comprehensive utilization of multiple energy sources and relates to a multi-time scale nested complementary scheduling method of electrochemical energy storage-hydro-wind-solar. Background Art

[0002] The high proportion of wind power and photovoltaic power generation grid-connected has aggravated the contradiction between the consumption of new energy and the safe and stable operation of the power system. The power system is facing the demand for flexible adjustment at different time scales. Hydropower has the characteristics of rapid start and stop and flexible operation. Large reservoir hydropower stations can meet the long-term, large-capacity and cross-seasonal flexibility adjustment needs of wind and solar energy. However, due to the unique performance and limited capacity of hydropower units, the load response speed is limited. Electrochemical energy storage has more flexible and rapid real-time response and short-term support capabilities. Combining it with hydropower can significantly reduce the scheduling risk of the system due to insufficient flexibility. To this end, the implementation of electrochemical energy storage-water, wind and solar multi-energy complementary scheduling, the coordinated use of the huge scale effect of cascade hydropower and the rapid response advantages of electrochemical energy storage, and the formation of multi-scale flexibility adjustment capabilities are of great significance for further enhancing the capacity of renewable energy consumption and improving the safe operation level of the power system.

[0003] However, current technologies are still mainly based on single technologies such as conventional cascade hydropower stations, pumped storage power stations or electrochemical energy storage power stations and complementary scheduling of wind and solar energy. There is little research on the coordinated scheduling and operation of hydropower stations and electrochemical energy storage power stations. In addition, the output characteristics and control strategies of hydropower units and electrochemical energy storage power stations are significantly different. The coordinated control strategy of a single time scale cannot ensure the optimization of system benefits. In view of the flexibility demand gap brought about by the large-scale grid connection of new energy, it is urgent to comprehensively consider the matching relationship between regulation demand and regulation resources on multiple time scales, and propose an optimized scheduling method that couples the advantages of cascade hydropower stations and electrochemical energy storage for multi-scale coordinated regulation. Summary of the invention

[0004] Purpose of the invention: The purpose of the present invention is to provide a multi-time-scale nested complementary scheduling method of electrochemical energy storage-water, wind and solar power to guide the multi-scale coordinated scheduling and operation of cascade hydropower stations and electrochemical energy storage to meet the multi-time-scale regulation needs of wind and solar energy.

[0005] Technical solution: The electrochemical energy storage-hydro-wind-solar multi-time scale nested complementary scheduling method of the present invention comprises the following steps: Establish a day-ahead hydro-wind-solar multi-energy complementary optimization dispatching model with the goal of maximizing daily power generation benefits, compensate and adjust the natural uncertainty of wind and solar output, and guide the formulation of a day-ahead joint power generation plan for the multi-energy complementary system; Establish a daily hydropower-wind-solar multi-energy complementary optimization dispatching model with the goal of minimizing the sum of the total power generation water consumption of the hydropower station and the penalty water consumption for unit start-up and shutdown and crossing the vibration zone during the dispatching period, and guide the hydropower station to formulate unit start-up and shutdown plans and output allocation plans; Propose quantitative indicators for the comprehensive flexibility of hydropower units and electrochemical energy storage, establish a real-time electrochemical energy storage-hydro-wind-solar multi-energy complementary optimization scheduling model with the goal of minimizing the comprehensive flexibility value, use electrochemical energy storage to access the hydro-wind-solar complementary system, complement the flexibility advantages of hydropower units, reduce the self-scheduling risk caused by the deviation of wind and solar forecasts caused by hydropower regulating alone, and track system load instructions in real time to reduce the risk of power shortage and abandonment in the complementary system; A multi-time scale nested dispatching model and nesting mechanism of day-ahead, intraday and real-time is established. The day-ahead dispatching model and intraday dispatching model are nested through power generation plan, and the intraday dispatching model and real-time dispatching model are nested through unit start-stop plan and output allocation plan. At the same time, the real-time dispatching model feeds back the final output allocation of the hydropower unit to the intraday dispatching model, and the intraday dispatching model feeds back the unit start-stop plan and output allocation plan to the day-ahead dispatching model, so as to realize hierarchical control of dispatching risks at different time scales of complementary systems.

[0006] Furthermore, the objective function of the day-ahead hydro-wind-solar multi-energy complementary optimization scheduling model is: , in, The combined daily power generation benefits of water, wind and photovoltaic power; For the day Time period; , , The hydropower station is Wind power, photovoltaic power and hydropower output during the period; , , They are the on-grid electricity prices for wind power, photovoltaic power and hydropower respectively; is the number of intraday periods; is the time interval.

[0007] Furthermore, the objective function of the daily hydro-wind-solar multi-energy complementary optimization scheduling model is: , in, It is the sum of the water consumption for power generation of the whole hydropower station and the penalty water consumption for starting and stopping the hydropower units and crossing the vibration zone; is the number of intraday periods; is the number of hydropower units; for Hydropower units in The power on / off status of the time period, 1 for power on and 0 for power off; for Hydropower units in The power on / off status of the time period, 1 for power on and 0 for power off; The power generation head is equal to Time Hydropower units bear the load water consumption; , They are Penalty water consumption for startup and shutdown of hydropower units; For the Hydropower units from Time period is up The number of times the time period crosses the vibration zone; For the The penalty water consumption corresponding to each hydropower unit passing through a vibration zone.

[0008] Furthermore, the comprehensive flexibility quantitative index of hydropower units and electrochemical energy storage is expressed as: , in, for Quantitative indicators of the comprehensive flexibility of hydropower units and electrochemical energy storage during the period; for Quantitative indicators of the flexibility of hydropower stations during different periods of time; for Quantitative indicators of the flexibility of time-slot electrochemical energy storage; Quantitative indicators of flexibility of hydropower plants It is expressed as: , in, , Respectively Hydropower units in Flexibility in adjusting time periods upwards and downwards; For the Hydropower units in The width of the output corridor in the time period; for The number of hydropower units in operation during the period; To take the absolute value; Quantitative indicators of flexibility of electrochemical energy storage It is expressed as: , in, , Electrochemical energy storage is The dischargeable and rechargeable amounts during the time period; For electrochemical energy storage, it can participate in regulating the total capacity.

[0009] Furthermore, a multi-time scale nested scheduling model and nested mechanism of day-ahead, intraday and real-time are established, including: The day-ahead and intraday optimization dispatching models are nested through power generation plans. The day-ahead dispatching comprehensively considers the power compensation and adjustment of hydropower, wind and solar power to declare the day-ahead power generation plan. The intraday dispatching aims to complete the day-ahead power generation plan, taking into account the start and stop and output change factors of the units during the dispatching period, and dynamically allocates the output of the hydropower units. The intraday and real-time optimization dispatching models are nested through the unit start and stop plans and output allocation plans. The intraday dispatching determines the optimal start and stop plans and output plans of the units in different dispatching periods, and the real-time dispatching determines the optimal hydropower unit output plan and the charging and discharging strategy of the electrochemical energy storage. At the same time, the real-time dispatching feeds back the final output allocation of the hydropower units to the intraday optimization dispatching model, and the intraday optimization dispatching model feeds back the unit start and stop plans and output allocation plans to the day-ahead optimization dispatching model, realizing the nested and complementary dispatching of electrochemical energy storage-hydropower, wind and solar power multi-energy and multi-time scales.

[0010] Furthermore, the intraday hydro-wind-solar multi-energy complementary optimization scheduling model realizes the dynamic allocation process of the output of hydropower units. First, a database of unit static load distribution tables for each unit under different unit start-stop combinations, generating heads and total output of the hydropower station is established. In the actual operation of the intraday hydro-wind-solar multi-energy complementary optimization scheduling model, a feasible unit output allocation plan is directly obtained from the database according to the total output of the hydropower station, generating heads and feasible unit start-up combinations; then, from the feasible combinations of unit output allocation plans, the optimal start-stop plans and output plans of units in different scheduling periods are determined through traversal search, with the goal of minimizing the total water consumption during the scheduling period; the model will determine the unit start-stop plans and output allocation plans within the future scheduled time according to the rolling update results of the scheduling period, and finally only execute the start-stop arrangements and output plans of the first scheduling period.

[0011] The electrochemical energy storage-hydro-wind-solar multi-time scale nested complementary scheduling system of the present invention comprises: The day-ahead dispatch model building unit is used to establish a day-ahead hydro-wind-solar multi-energy complementary optimization dispatch model with the goal of maximizing daily power generation benefits, to compensate and adjust the natural uncertainty of wind and solar output, and to guide the formulation of a day-ahead joint power generation plan for the multi-energy complementary system; The intraday dispatch model construction unit is used to establish an intraday hydropower-wind-solar multi-energy complementary optimization dispatch model with the goal of minimizing the sum of the total power generation water consumption of the hydropower station and the penalty water consumption for unit start-up and shutdown and crossing the vibration zone during the dispatch period, and guide the hydropower station to formulate unit start-up and shutdown plans and output allocation plans; The real-time dispatch model construction unit is used to propose quantitative indicators of the comprehensive flexibility of hydropower units and electrochemical energy storage, establish a real-time electrochemical energy storage-hydro-wind-solar multi-energy complementary optimization dispatch model with the goal of minimizing the comprehensive flexibility value, use electrochemical energy storage to access the hydro-wind-solar complementary system, complement the flexibility advantages of hydropower units, reduce the self-dispatching risk caused by the deviation of wind and solar forecasts caused by hydropower alone, and track system load instructions in real time to reduce the risk of power shortage and abandonment in the complementary system; The nested model construction and nested dispatching unit are used to establish a multi-time scale nested dispatching model of day-ahead, intraday and real-time and a step-by-step information feedback mechanism. The nesting of the day-ahead dispatching model and the intraday dispatching model is realized through the power generation plan, and the nesting of the intraday dispatching model and the real-time dispatching model is realized through the unit start-stop plan and the output allocation plan. At the same time, the real-time dispatching model feeds back the final output allocation of the hydropower unit to the intraday dispatching model, and the intraday dispatching model feeds back the unit start-stop plan and the output allocation plan to the day-ahead dispatching model, so as to realize the hierarchical control of the dispatching risks on different time scales of the complementary system.

[0012] The electronic device of the present invention comprises: A memory storing executable program code; a processor coupled to the memory; The processor calls the executable program code stored in the memory to execute the steps of the electrochemical energy storage-hydro-wind-solar multi-time scale nested complementary scheduling method.

[0013] The present invention provides a computer-readable storage medium, which stores computer instructions. When the computer instructions are called, they are used to execute the steps of the electrochemical energy storage-hydro-wind-solar multi-time scale nested complementary scheduling method.

[0014] A computer program product described in the present invention includes a computer program / instruction, which, when executed by a processor, implements the steps of the electrochemical energy storage-hydro-wind-solar multi-time scale nested complementary scheduling method.

[0015] Beneficial effects: Compared with the prior art, the significant technical effects of the present invention are: (1) The proposed day-ahead-intraday-real-time multi-time scale nested dispatch model meets the dispatch requirements of the electrochemical energy storage-hydro-wind-solar complementary system at different time scales. The day-ahead model can ensure the optimal power compensation benefit of the complementary system at the day-ahead scale; the intraday model minimizes the risk of frequent start-up and shutdown of hydropower units due to complementary wind and solar power during the foreseeable period while meeting the power generation plan; the real-time model minimizes the self-dispatching risk caused by the deviation of wind and solar power forecasts caused by the separate adjustment of hydropower as much as possible, and reduces the risk of power shortage and abandonment of the complementary system by real-time tracking of system load instructions; (2) The multi-time-scale nested dispatching method of electrochemical energy storage-hydropower-wind-solar complementarity not only compensates for the random fluctuation characteristics of wind and solar power output in the day-ahead-intraday dispatching stage, thereby improving the output stability of the complementary system, but also uses the flexible adjustment capabilities of electrochemical energy storage and hydropower units to compensate for the forecast uncertainty of wind and solar power output at the real-time level. While improving the wind and solar power consumption level and the power supply reliability of the complementary system, it reduces the risk of frequent crossing of vibration zones caused by hydropower units responding alone to wind and solar power forecast deviations. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 Flexibility supply and demand framework for multi-energy complementary systems; Figure 2 is a flow chart of the method of the present invention; Figure 3 It is a nested scheduling model framework for multi-energy complementarity and multi-time scales. DETAILED DESCRIPTION

[0017] The present invention is described in detail below in conjunction with the accompanying drawings and specific implementation methods: In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the present invention is further described below in conjunction with specific implementation methods.

[0018] like Figure 1 As shown in the flexible supply and demand framework of the multi-energy complementary system, the multi-energy complementary system faces the demand for flexibility adjustment at different time scales. Considering that the power adjustment amplitude of conventional hydropower units is large and the duration is long, it can provide relatively stable energy for the system, but its response time is longer than that of energy storage devices, which is suitable for large-capacity and long-term support; electrochemical energy storage has a faster and flexible response capability, but the overall scale is very small, and it can only provide short-term support on the scale of several hours, which is mainly used to respond to short-term and ultra-short-term load fluctuations. Therefore, the present invention proposes an electrochemical energy storage-water, wind and solar multi-time scale nested complementary scheduling method, which adopts cascade hydropower stations to deal with the wind and solar output fluctuations on the day-ahead and intra-day scales of the system, and adopts hydropower-electrochemical energy storage to deal with the real-time scale wind and solar output fluctuations.

[0019] like Figure 2 As shown, the electrochemical energy storage-hydro-wind-solar multi-time scale nested complementary scheduling method of the present invention comprises the following steps: S1. Establish a day-ahead water, wind and solar multi-energy complementary optimization dispatching model (referred to as: day-ahead dispatching model); Taking into account the day-ahead wind and solar forecast information, a day-ahead hydro-wind-solar multi-energy complementary optimization scheduling model is established with the goal of maximizing daily power generation efficiency. The power compensation effect of hydropower on wind and solar power is fully utilized, and compensation and adjustment are made for the natural uncertainty of wind and solar power output, so as to guide the formulation of the day-ahead joint power generation plan of the multi-energy complementary system.

[0020] (1) Objective function: The core of the day-ahead hydropower, wind-solar multi-energy complementary optimization dispatching model is to utilize the storage and regulation capacity of hydropower to compensate for the natural uncertainties of wind-solar output, such as randomness, intermittency, and volatility, change the long-term water level control mode of the reservoir, and improve the comprehensive utilization efficiency of energy. The day-ahead hydropower, wind-solar multi-energy complementary optimization dispatching model uses the day as the dispatching period and 15 minutes as the dispatching period. It takes the maximum daily power generation benefit of hydropower, wind-solar and photovoltaic power generation as the dispatching target, and takes the reservoir capacity as the decision variable. Its objective function is shown in formula (1): (1), in, The combined daily power generation benefits of water, wind and photovoltaic power; For the day Time period; , , The hydropower station is Wind power, photovoltaic power and hydropower output during the period; , , They are the on-grid electricity prices for wind power, photovoltaic power and hydropower respectively; is the number of intraday periods; It is a short-term scheduling period.

[0021] (2) Constraints: In addition to meeting the constraints of water balance, upper and lower limits of storage capacity, upper and lower limits of outflow flow, upper and lower limits of power generation output, reservoir characteristic curves, etc., the water, wind and solar multi-energy complementary optimization scheduling model also needs to meet the constraints of wind power and photovoltaic installed capacity and power grid transmission channel. (21) Water balance constraints: (2), in, , The reservoirs are Initial and final storage capacity of the time period; , Reservoir No. Inbound and outbound traffic during a period; is the time interval.

[0022] (22) Reservoir capacity constraints: (3), in, It is the dead storage capacity of the reservoir; The reservoir is The maximum allowable storage capacity for each time period is the storage capacity corresponding to the flood control limit water level during the flood season and the storage capacity corresponding to the normal water storage level in other periods.

[0023] (23) Outbound flow range constraints: (4), in, It is the minimum ecological water flow required downstream; is the maximum allowable discharge flow.

[0024] (24) Power generation flow constraints: (5), in, is the minimum power generation flow; is the maximum power generation flow; for The power generation flow during the period.

[0025] (25) Power station output constraints: (6), (7), (8), in, , , They are Output of hydropower stations, wind power stations, and photovoltaic power stations during the period; , , They are the minimum outputs of hydropower stations, wind power stations, and photovoltaic power stations respectively; , , They are the maximum outputs of hydropower stations, wind power stations and photovoltaic power stations respectively.

[0026] (26) Constraints on power grid transmission channels: (9), in, , , They are Output of hydropower stations, wind power stations, and photovoltaic power stations during the period; is the capacity of the transport channel.

[0027] S2. Establish a daily water-wind-solar multi-energy complementary optimization dispatching model (referred to as: daily dispatching model); Taking into account the rolling update of wind and solar power forecast information every 15 minutes in the next hour, a daily hydro-wind-solar multi-energy complementary optimization scheduling model is established with the goal of minimizing the sum of the total water consumption of the hydropower station and the penalty water consumption for unit start-up and shutdown and crossing the vibration zone during the scheduling period. This model guides hydropower stations to formulate reasonable unit start-up and shutdown plans and output allocation plans, and reduces the risk of frequent start-up and shutdown of hydropower units caused by complementary wind and solar power during the forecast period.

[0028] (1) Objective function: The intraday dispatch model combines the forecast information of wind and solar power that is updated in the next hour, takes 1 hour as the dispatch period and 15 minutes as the dispatch period, and takes into account the drastic changes in the output of the hydropower station caused by the complementary wind and solar power, which brings the risk of frequent start and stop of hydropower units and crossing the vibration zone. The goal is to minimize the sum of the water consumption of the whole hydropower station and the penalty water consumption of the start and stop of the units and crossing the vibration zone during the dispatch period. The start and stop plan and output allocation plan of the hydropower station under the water-wind-solar complementary mode are formulated, and the objective function is formed as follows: (10), in, It is the sum of the water consumption for power generation of the whole hydropower station and the penalty water consumption for starting and stopping the units and crossing the vibration zone; is the number of intraday periods; is the number of hydropower units; for Hydropower units in The power on / off status of the time period, 1 for power on and 0 for power off; for Hydropower units in The power on / off status of the time period, 1 for power on and 0 for power off; The power generation head is equal to Time Hydropower units bear the load The water consumption can be obtained by checking the NHQ curve of the corresponding unit; , They are Penalty water consumption for startup and shutdown of hydropower units; For the Hydropower units from Time period is up The number of times the time period crosses the vibration zone; For the The penalty water consumption corresponding to each hydropower unit passing through a vibration zone.

[0029] (2) Constraints: (21) Hydropower station output boundary constraints: (11), (12), in, for The output that the hydropower station needs to bear during the period; for The total output of water, wind and solar power planned by the day-ahead dispatch model during the time period; , They are Wind power and photovoltaic output during the period; For the Hydropower unit Output during the time period; is the number of hydroelectric units.

[0030] (22) Output constraints of hydropower units: (13), in, For the Hydropower unit Output during the time period; For the Hydropower unit The generating head during the period; For the Hydropower unit The power generation flow during the period.

[0031] (23) Vibration zone constraints: (14), (15), (16), in, , Respectively Hydropower unit Maximum and minimum output limits for each time period; For the Hydropower unit The lower limit of the first vibration zone of the time period; For the Hydropower unit The period The upper limit of the vibration zone; For the Hydropower unit The period The lower limit of the vibration zone; For the Hydropower unit The period The upper limit of the vibration zone; is the number of vibration zones of the hydropower station.

[0032] (24) Minimum start-up and shutdown time constraints: (17), (18), in, , Respectively Hydropower units to Continuous on time and continuous off time during the period; , Respectively The shortest startup and shutdown time of each hydropower unit.

[0033] (25) Maximum climbing constraint: (19), in, For the The maximum climbing value of the hydropower unit; For the Hydropower unit Output during the period.

[0034] S3. Establish a real-time electrochemical energy storage-water-wind-solar multi-energy complementary optimization scheduling model (referred to as: real-time scheduling model); Since there is still a forecast deviation for the ultra-short-term output of wind and solar, real-time electrochemical energy storage-hydro, wind and solar multi-energy complementary scheduling needs to adjust the output distribution of hydropower units, and use electrochemical energy storage batteries to store or release electricity to respond to ultra-short-term forecast deviations, thereby meeting the real-time load instructions issued by the power grid. Therefore, the load deviation that the multi-energy complementary system needs to adjust is the deviation between the ultra-short-term forecast output of wind and solar and the real-time output. ,in for Wind power forecast output for each period, for The actual wind power output during the period, for Photovoltaic output forecast for each period, for Actual photovoltaic output during the period. In the water-wind-solar complementary mode, if only hydropower is used to respond to the wind-solar forecast deviation, the hydropower unit will face the risk of frequently crossing the vibration zone during the output adjustment process. In order to minimize the occurrence of adverse conditions caused by the hydropower unit crossing the vibration zone, real-time scheduling uses electrochemical energy storage to access the water-wind-solar complementary system, complement the flexibility advantages of the hydropower unit, and establish a real-time electrochemical energy storage-water-wind-solar multi-energy complementary scheduling model. The study proposes quantitative indicators for the comprehensive flexibility of hydropower units and electrochemical energy storage, and establishes a real-time electrochemical energy storage-water-wind-solar multi-energy complementary optimization scheduling model with the minimum comprehensive flexibility value as the goal. Electrochemical energy storage is used to access the water-wind-solar complementary system, complement the flexibility advantages of the hydropower unit, and through the coordinated scheduling of hydropower and electrochemical energy storage, the self-scheduling risk caused by the hydropower adjusting the wind-solar forecast deviation alone is reduced, and the system load instructions are tracked in real time to reduce the risk of power shortage and abandonment in the complementary system.

[0035] (1) Objective function: The uncertainty of future wind and solar power output leads to uncertain demand for regulation flexibility, which requires sufficient regulation flexibility supply in both the upward and downward directions. Based on this, a quantitative index of comprehensive flexibility for coordinated regulation of hydropower and electrochemical energy storage is proposed, as shown in formula (20). The smaller the value of comprehensive flexibility, the better the comprehensive flexibility of hydropower-electrochemical energy storage.

[0036] The regulation flexibility of hydropower is limited by the vibration zone of the unit, and the output of the unit will fall into different output corridors. In order to avoid the influence of different output corridors on the flexibility of hydropower, the formula is normalized to form a quantitative index of hydropower flexibility, see formula (21); the regulation flexibility of electrochemical energy storage is mainly constrained by its dischargeable capacity and rechargeable capacity, and the calculation method of its flexible quantitative index is shown in formula (22); (20), (twenty one), (twenty two), in, for Quantitative indicators of the comprehensive flexibility of hydropower units and electrochemical energy storage during the period; for Quantitative indicators of the flexibility of hydropower stations during different periods of time; for Quantitative indicators of the flexibility of time-slot electrochemical energy storage; , Respectively Hydropower units in Flexibility in adjusting time periods upwards and downwards; For the Hydropower units in The width of the output corridor (formed by the unit operation constraints) in the time period; for The number of hydropower units in operation during the period; , Electrochemical energy storage is The dischargeable and rechargeable amounts during the time period; Electrochemical energy storage can participate in regulating the total capacity; To take the absolute value.

[0037] (2) Constraints: The real-time dispatching model needs to meet the relevant constraints of reservoirs, hydropower stations and hydropower units described before and during the day, as well as the relevant constraints of electrochemical energy storage batteries and the boundary conditions provided by the intraday dispatching model.

[0038] (21) Energy balance constraints for electrochemical energy storage: (twenty three), (twenty four), in, for The remaining capacity of the electrochemical energy storage at the end of the time period; for The remaining capacity of the electrochemical energy storage at the end of the time period; It is the charge and discharge power of electrochemical energy storage (charging is positive and discharging is negative); , They are the charging efficiency and discharging efficiency of electrochemical energy storage respectively; is the time interval.

[0039] (22) Avoid overcharge and over discharge constraints: (25), (26), in, , are the maximum and minimum charge rates of electrochemical energy storage, respectively; for The charge rate of electrochemical energy storage during a period of time; is the rated capacity of the energy storage battery.

[0040] (23) Avoid frequent start-stop constraints: (27), in, , Respectively Hydropower unit The start and stop status of the time period real-time scheduling model and the start and stop status of the intraday scheduling model.

[0041] S4. Establish multi-time scale nested scheduling and step-by-step information feedback in day-ahead, intra-day and real-time; Multi-energy complementary scheduling is a multi-dimensional, non-convex, nonlinear optimization problem, which contains multiple decision variables, including reservoir scheduling at different time scales, unit start-stop plans, unit output distribution, and charge and discharge power of electrochemical energy storage. The present invention uses the DP algorithm for solution, but the problem of "dimensionality disaster" may occur in the process of model solution using the DP algorithm. In order to avoid this problem, the present invention adopts a hierarchical control method for multi-time scale nested models, as shown below: (1) The day-ahead scheduling model takes into account the complementary characteristics of hydropower, wind power, and photovoltaic power. The scheduling period is 1 day, and the scheduling time interval is 15 minutes. With the goal of maximizing the daily power generation benefit of the combined hydropower, wind power, and photovoltaic power system, the reservoir storage capacity is used as the decision variable, and DP traversal search is used to maximize the daily power generation of the multi-energy complementary system.

[0042] (2) The intra-day scheduling model has a scheduling period of 1 hour and a scheduling time interval of 15 minutes. This model takes into account factors such as the start-stop and output changes of the units during the scheduling period and is a dynamic allocation process of the hydropower unit output. To improve the computational efficiency of the algorithm, a database of the unit static load distribution table for each unit under different unit start-stop combinations, generating heads, and total hydropower station output is first established. In the actual operation of the intra-day scheduling model, according to the total output of the hydropower station, the generating head, and the feasible unit startup combinations, a feasible unit output allocation plan is directly obtained from the database. Then, from the feasible combinations of the unit output allocation plan, through DP traversal search, the optimal start-stop plan and output plan of the units for different scheduling time intervals are determined, with the goal of minimizing the total water consumption during the scheduling period. The results of this model are updated every 15 minutes, determining the unit start-stop plan and output allocation plan for the next hour, and finally only the start-stop arrangement and output plan for the first scheduling time interval, that is, the next 15 minutes, are executed.

[0043] (3) The real-time scheduling model has a scheduling period of 15 minutes and a scheduling time interval of 5 minutes. With the goal of optimizing the comprehensive flexibility of hydropower-electrochemical energy storage at the end of the scheduling time interval, DP traversal search is used to determine the optimal hydropower unit output plan and the charge-discharge strategy of the electrochemical energy storage.

[0044] Establish day-ahead - intra-day - real-time multi-time-scale nested scheduling and step-by-step information feedback to achieve top-down nesting: (as Figure 3 shown): The day-ahead and intra-day scheduling models are nested through the generation plan. The day-ahead scheduling comprehensively considers the power compensation regulation of hydropower, wind power, and photovoltaic power to declare the day-ahead generation plan. The intra-day scheduling aims to complete the day-ahead generation plan, taking into account factors such as the start-stop and output changes of the units during the scheduling period, and dynamically allocates the output of the hydropower units; The intra-day and real-time scheduling models are nested through the unit start-stop plan and output allocation plan. The intra-day scheduling determines the optimal start-stop plan and output plan of the units for different scheduling time intervals, and the real-time scheduling determines the optimal hydropower unit output plan and the charge-discharge strategy of the electrochemical energy storage; At the same time, the real-time scheduling model feeds back the final output allocation of the hydropower units to the intra-day scheduling model, and the intra-day scheduling model feeds back the unit start-stop plan and output allocation plan to the day-ahead scheduling model, realizing the multi-time-scale nested complementary scheduling of electrochemical energy storage - hydropower, wind power, and photovoltaic power.

[0045] The present invention takes a multi-energy complementary system as an example and applies the above scheduling method to carry out analysis. The system includes a 1280MW hydropower station, an 850MW photovoltaic power station and an 85MW / 170MWh lithium-ion energy storage power station. The specific parameters of the hydropower station are shown in Table 1.

[0046] Table 1 Related parameters of Longyangxia Hydropower Station

[0047] By applying the above-mentioned electrochemical energy storage-hydro-wind-solar multi-time nested complementary scheduling method, and setting hydro-solar independent operation and hydro-solar complementary scheduling as comparison strategies. The power generation of the three scheduling strategies at multiple time scales during the scheduling period is shown in Table 2 below. Compared with the independent operation of hydro-solar, the actual power generation of the hydro-solar storage complementary and hydro-solar complementary systems increased by 3.04% and 2.93% respectively. The electrochemical energy storage-hydro-solar multi-energy complementary operation did not experience power shortage and power abandonment during the entire scheduling; while the hydro-solar complementary operation system still had a small amount of power shortage and power abandonment at the real-time level, with a power abandonment of 60,000 kWh and a power shortage of 30,000 kWh. It can be seen that the hydro-solar complementary operation has significantly reduced the risk of power shortage and abandonment of the hydro-solar system, but it also shows that the addition of electrochemical energy storage has made the complementary system have better power supply reliability.

[0048] Table 2 Power generation statistics of three different dispatch strategies during the dispatch period (10,000 kW·h)

[0049] The electrochemical energy storage-hydro-wind-solar multi-time scale nested complementary scheduling system of the present invention comprises: The day-ahead dispatch model building unit is used to establish a day-ahead hydro-wind-solar multi-energy complementary optimization dispatch model with the goal of maximizing daily power generation benefits, to compensate and adjust the natural uncertainty of wind and solar output, and to guide the formulation of a day-ahead joint power generation plan for the multi-energy complementary system; The intraday dispatch model construction unit is used to establish an intraday hydropower-wind-solar multi-energy complementary optimization dispatch model with the goal of minimizing the sum of the total power generation water consumption of the hydropower station and the penalty water consumption for unit start-up and shutdown and crossing the vibration zone during the dispatch period, and guide the hydropower station to formulate unit start-up and shutdown plans and output allocation plans; The real-time dispatch model construction unit is used to propose quantitative indicators of the comprehensive flexibility of hydropower units and electrochemical energy storage, establish a real-time electrochemical energy storage-hydro-wind-solar multi-energy complementary optimization dispatch model with the goal of minimizing the comprehensive flexibility value, use electrochemical energy storage to access the hydro-wind-solar complementary system, complement the flexibility advantages of hydropower units, reduce the self-dispatching risk caused by the deviation of wind and solar forecasts caused by hydropower alone, and track system load instructions in real time to reduce the risk of power shortage and abandonment in the complementary system; The nested model construction and nested dispatching unit are used to establish a multi-time scale nested dispatching model of day-ahead, intraday and real-time and a step-by-step information feedback mechanism. The nesting of the day-ahead dispatching model and the intraday dispatching model is realized through the power generation plan, and the nesting of the intraday dispatching model and the real-time dispatching model is realized through the unit start-stop plan and the output allocation plan. At the same time, the real-time dispatching model feeds back the final output allocation of the hydropower unit to the intraday dispatching model, and the intraday dispatching model feeds back the unit start-stop plan and the output allocation plan to the day-ahead dispatching model, so as to realize the hierarchical control of the dispatching risks on different time scales of the complementary system.

[0050] The electronic device of the present invention comprises: A memory storing executable program code; a processor coupled to the memory; The processor calls the executable program code stored in the memory to execute the steps of the electrochemical energy storage-hydro-wind-solar multi-time scale nested complementary scheduling method.

[0051] The present invention provides a computer-readable storage medium, which stores computer instructions. When the computer instructions are called, they are used to execute the steps of the electrochemical energy storage-hydro-wind-solar multi-time scale nested complementary scheduling method.

[0052] A computer program product described in the present invention includes a computer program / instruction, which, when executed by a processor, implements the steps of the electrochemical energy storage-hydro-wind-solar multi-time scale nested complementary scheduling method.

Claims

1. A multi-time scale nested complementary scheduling method for electrochemical energy storage, water, wind and solar, characterized in that: The following steps are involved: Establish a day-ahead hydro-wind-solar multi-energy complementary optimization dispatching model with the goal of maximizing daily power generation benefits, compensate and adjust the natural uncertainty of wind and solar output, and guide the formulation of a day-ahead joint power generation plan for the multi-energy complementary system; Establish a daily hydropower-wind-solar multi-energy complementary optimization dispatching model with the goal of minimizing the sum of the total power generation water consumption of the hydropower station and the penalty water consumption for unit start-up and shutdown and crossing the vibration zone during the dispatching period, and guide the hydropower station to formulate unit start-up and shutdown plans and output allocation plans; Propose quantitative indicators for the comprehensive flexibility of hydropower units and electrochemical energy storage, establish a real-time electrochemical energy storage-hydro-wind-solar multi-energy complementary optimization scheduling model with the goal of minimizing the comprehensive flexibility value, use electrochemical energy storage to access the hydro-wind-solar complementary system, complement the flexibility advantages of hydropower units, reduce the self-scheduling risk caused by the deviation of wind and solar forecasts caused by hydropower regulating alone, and track system load instructions in real time to reduce the risk of power shortage and abandonment in the complementary system; A multi-time scale nested dispatching model and nesting mechanism of day-ahead, intraday and real-time is established. The day-ahead dispatching model and intraday dispatching model are nested through power generation plan, and the intraday dispatching model and real-time dispatching model are nested through unit start-stop plan and output allocation plan. At the same time, the real-time dispatching model feeds back the final output allocation of the hydropower unit to the intraday dispatching model, and the intraday dispatching model feeds back the unit start-stop plan and output allocation plan to the day-ahead dispatching model, so as to realize hierarchical control of dispatching risks at different time scales of complementary systems.

2. The electrochemical energy storage-hydro-wind-solar multi-time scale nested complementary scheduling method according to claim 1 is characterized in that: The objective function of the day-ahead hydro-wind-solar multi-energy complementary optimization scheduling model is: ， in, The combined daily power generation benefits of water, wind and photovoltaic power; For the day Time period; , , The hydropower station is Wind power, photovoltaic power and hydropower output during the period; , , They are the on-grid electricity prices for wind power, photovoltaic power and hydropower respectively; is the number of intraday periods; is the time interval.

3. The electrochemical energy storage-hydro-wind-solar multi-time scale nested complementary scheduling method according to claim 1 is characterized in that: The objective function of the daily hydro-wind-solar multi-energy complementary optimization scheduling model is: ， in, It is the sum of the water consumption for power generation of the whole hydropower station and the penalty water consumption for starting and stopping the hydropower units and crossing the vibration zone; n is the number of intraday periods; is the number of hydropower units; for Hydropower units in The power on / off status of the time period, 1 for power on and 0 for power off; for Hydropower units in The power on / off status of the time period, 1 for power on and 0 for power off; The power generation head is equal to Time Hydropower units bear the load water consumption; , They are Penalty water consumption for startup and shutdown of hydropower units; For the Hydropower units from Time period is up The number of times the time period crosses the vibration zone; For the The penalty water consumption corresponding to each hydropower unit passing through a vibration zone.

4. The electrochemical energy storage-hydro-wind-solar multi-time scale nested complementary scheduling method according to claim 1 is characterized in that: The quantitative index of the comprehensive flexibility of hydropower units and electrochemical energy storage is expressed as: ， in, for Quantitative indicators of the comprehensive flexibility of hydropower units and electrochemical energy storage during the period; for Quantitative indicators of the flexibility of hydropower stations during different periods of time; for Quantitative indicators of the flexibility of time-slot electrochemical energy storage; Quantitative indicators of flexibility of hydropower plants It is expressed as: ， in, , Respectively Hydropower units in Flexibility in adjusting time periods upwards and downwards; For the Hydropower units in The width of the output corridor in the time period; for The number of hydropower units in operation during the period; To take the absolute value; Quantitative indicators of flexibility of electrochemical energy storage It is expressed as: ， in, , Electrochemical energy storage The dischargeable and rechargeable amounts during the time period; For electrochemical energy storage, it can participate in regulating the total capacity.

5. The electrochemical energy storage-hydro-wind-solar multi-time scale nested complementary scheduling method according to claim 1 is characterized in that: Establish a multi-time scale nested scheduling model and nested mechanism of day-ahead, intraday and real-time, including: The day-ahead and intraday optimization dispatching models are nested through power generation plans. The day-ahead dispatching comprehensively considers the power compensation and adjustment of hydropower, wind and solar power to declare the day-ahead power generation plan. The intraday dispatching aims to complete the day-ahead power generation plan, taking into account the start and stop and output change factors of the units during the dispatching period, and dynamically allocates the output of the hydropower units. The intraday and real-time optimization dispatching models are nested through the unit start and stop plans and output allocation plans. The intraday dispatching determines the optimal start and stop plans and output plans of the units in different dispatching periods, and the real-time dispatching determines the optimal hydropower unit output plan and the charging and discharging strategy of the electrochemical energy storage. At the same time, the real-time dispatching feeds back the final output allocation of the hydropower units to the intraday optimization dispatching model, and the intraday optimization dispatching model feeds back the unit start and stop plans and output allocation plans to the day-ahead optimization dispatching model, realizing the nested and complementary dispatching of electrochemical energy storage-hydropower, wind and solar power multi-energy and multi-time scales.

6. The electrochemical energy storage-hydro-wind-solar multi-time scale nested complementary scheduling method according to claim 1 is characterized in that: The intraday hydro-wind-solar multi-energy complementary optimization scheduling model realizes the dynamic allocation process of the output of hydropower units. First, a database of unit static load distribution tables for each unit under different unit start-stop combinations, generating heads and total output of the hydropower station is established. In the actual operation of the intraday hydro-wind-solar multi-energy complementary optimization scheduling model, a feasible unit output allocation plan is directly obtained from the database according to the total output of the hydropower station, generating heads and feasible unit start-up combinations; then, from the feasible combinations of unit output allocation plans, with the goal of minimizing the total water consumption during the scheduling period, the optimal start-stop plan and output plan of the units in different scheduling periods are determined through traversal search; the model will determine the unit start-stop plan and output allocation plan within the future scheduled time according to the rolling update results of the scheduling period, and finally only execute the start-stop arrangement and output plan of the first scheduling period.

7. An electrochemical energy storage-hydro-wind-solar multi-time scale nested complementary scheduling system, characterized in that: include: The day-ahead dispatch model building unit is used to establish a day-ahead hydro-wind-solar multi-energy complementary optimization dispatch model with the goal of maximizing daily power generation benefits, to compensate and adjust the natural uncertainty of wind and solar output, and to guide the formulation of a day-ahead joint power generation plan for the multi-energy complementary system; The intraday dispatch model construction unit is used to establish an intraday hydropower-wind-solar multi-energy complementary optimization dispatch model with the goal of minimizing the sum of the total power generation water consumption of the hydropower station and the penalty water consumption for unit start-up and shutdown and crossing the vibration zone during the dispatch period, and guide the hydropower station to formulate unit start-up and shutdown plans and output allocation plans; The real-time dispatch model construction unit is used to propose quantitative indicators of the comprehensive flexibility of hydropower units and electrochemical energy storage, establish a real-time electrochemical energy storage-hydro-wind-solar multi-energy complementary optimization dispatch model with the goal of minimizing the comprehensive flexibility value, use electrochemical energy storage to access the hydro-wind-solar complementary system, complement the flexibility advantages of hydropower units, reduce the self-dispatching risk caused by the deviation of wind and solar forecasts caused by hydropower alone, and track system load instructions in real time to reduce the risk of power shortage and abandonment in the complementary system; The nested model construction and nested dispatching unit are used to establish the day-ahead-intraday-real-time multi-time scale nested dispatching model and nesting mechanism. The day-ahead dispatching model and the intraday dispatching model are nested through the power generation plan, and the intraday dispatching model and the real-time dispatching model are nested through the unit start-stop plan and output allocation plan. At the same time, the real-time dispatching model feeds back the final output allocation of the hydropower unit to the intraday dispatching model, and the intraday dispatching model feeds back the unit start-stop plan and output allocation plan to the day-ahead dispatching model, so as to realize the hierarchical control of the dispatching risks on different time scales of the complementary system.

8. An electronic device, characterized in that: The device comprises: A memory storing executable program code; a processor coupled to the memory; The processor calls the executable program code stored in the memory to execute the steps of the electrochemical energy storage-hydro-wind-solar multi-time scale nested complementary scheduling method described in any one of claims 1-6.

9. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer instructions, which, when called, are used to execute the steps of the electrochemical energy storage-hydro-wind-solar multi-time-scale nested complementary scheduling method as described in any one of claims 1 to 6.

10. A computer program product comprising a computer program / instructions, characterized in that When the computer program / instructions are executed by the processor, the steps of the electrochemical energy storage-hydro-wind-solar multi-time scale nested complementary scheduling method according to any one of claims 1 to 6 are implemented.

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