Hybrid energy storage scheduling method, system, equipment and medium

Abstract

The invention discloses a hybrid energy storage scheduling method, system, equipment and medium in the technical field of electric power energy storage, and the method comprises the steps: building a'gravity-electrochemistry 'hybrid energy storage operation economy model based on the characteristics of gravity energy storage and electrochemical energy storage, and carrying out the quantitative representation of the operation cost of a hybrid energy storage system participating in system adjustment, taking the minimum sum of the total operation cost of the system and the power abandoning penalty as an optimization target, considering the power balance constraint, the system safety constraint and the operation constraint of a power supply and energy storage, and establishing a hybrid energy storage scheduling optimization model for peak regulation and frequency modulation of the high-proportion new energy system; and finally, taking power supply and load data of the high-proportion new energy system as input, solving the optimization model based on an interior point method, and obtaining an optimal scheduling scheme of hybrid energy storage participating in peak regulation and frequency modulation of the system. According to the scheme, the problem that there is no effective method for supporting scheduling strategy making in the prior art is solved, the adjustment requirement of a high-proportion new energy system can be met, and the new energy consumption level is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of electric power energy storage, and particularly to a hybrid energy storage scheduling method, system, device and medium for regulating a high-proportion new energy system. Background Art

[0002] With the continuous increase in the proportion of new energy in the power system, the uncertainty and uncontrollability of the output of wind and solar power generation have significantly increased the difficulty of peak-valley regulation of the system. On the one hand, during the high-output period of wind and solar, the excess power generation will lead to the phenomenon of curtailment of wind and light; on the other hand, there may be a shortage of power generation during the peak load period. In addition, due to the intermittency and volatility of new energy output, the frequency regulation requirements of high-proportion new energy systems are also higher. However, the decreasing proportion of traditional thermal power units that undertake the regulation function has made the available peak shaving and frequency modulation resources in the system increasingly tense. Energy storage, as an important regulation resource in the new power system, can effectively relieve the peak shaving and frequency modulation pressures of the system under the condition of high-proportion new energy access.

[0003] Electrochemical energy storage is the most widely used new energy storage technology at present. In addition to playing the role of peak shaving and valley filling, it is also suitable for participating in frequency regulation due to its fast response speed; while gravity energy storage has the advantages of stable output, long discharge duration, high energy conversion efficiency, etc., and is an excellent peak shaving resource. The "gravity-electrochemical" hybrid energy storage combines the advantages of both, and can play a key regulation role in high-proportion new energy systems and improve the new energy consumption level.

[0004] Regarding the coordinated scheduling problem of peak shaving and frequency modulation in high-proportion new energy systems, there is a lack of targeted methods to support the formulation of scheduling strategies. Specifically, there is currently a lack of mature operation scheduling methods for the "gravity-electrochemical" hybrid energy storage to participate in the peak shaving and frequency modulation of the power system. Summary of the Invention

[0005] Aiming at the deficiencies of the prior art, the present invention provides a hybrid energy storage scheduling method for regulating a high-proportion new energy system to solve the problem that there is no mature and effective method in the above prior art to support the formulation of scheduling strategies.

[0006] To achieve the above objectives, the present invention is realized through the following technical solutions:

[0007] A hybrid energy storage scheduling method adopts the following steps:

[0008] S1, establish an operating economy model of the hybrid energy storage to quantitatively characterize the operating cost of the hybrid energy storage system participating in the regulation of the power system. The hybrid energy storage system at least includes gravity energy storage and electrochemical energy storage. The operating cost of the hybrid energy storage system participating in the regulation of the power system at least includes the operating cost C of gravity energy storage participating in the regulation of the power system Gand the operating cost C of the electrochemical energy storage participating in the power system regulation B , the grid-side gravity energy storage participates in the system peak shaving, and the operating cost C of the gravity energy storage participating in the power system regulation G is a linear function of the charge-discharge amount, and is specifically calculated using the following formula:

[0009]

[0010] where c GE is the operating cost per unit charge-discharge amount of the gravity energy storage, are the charge and discharge powers of the gravity energy storage at the scheduling period t respectively, T is the total number of operating scheduling periods, and Δt is the time step of the operating scheduling; the grid-side electrochemical energy storage participates in the system peak shaving and frequency modulation, and the operating cost C of the electrochemical energy storage participating in the power system regulation B is a linear function of the charge-discharge amount and the frequency modulation reserve capacity, and is specifically calculated using the following formula:

[0011]

[0012] where c BE is the operating cost per unit charge-discharge amount of the electrochemical energy storage, and c BF is the operating cost per unit frequency modulation reserve capacity provided by the electrochemical energy storage during the operating scheduling period, R B,t are the charge-discharge power and the frequency modulation reserve capacity of the electrochemical energy storage at the scheduling period t respectively;

[0013] S2, with the sum F of the total system operating cost and the curtailment penalty C CP being the optimization objective, considering the regulation requirements of the high-proportion new energy system and the operating characteristics of the facilities in the system to set the constraint conditions, and establishing a hybrid energy storage scheduling optimization model for the regulation of the high-proportion new energy power system;

[0014] S3, using the power source and load data of the high-proportion new energy system as the input, solving the hybrid energy storage scheduling optimization model based on the interior point method, and obtaining the optimal scheduling scheme for the hybrid energy storage to participate in the power system peak shaving and frequency modulation.

[0015] Preferably, the total system operating cost in the optimization objective with the sum F of the total system operating cost and the curtailment penalty C CP at least includes the thermal power operating cost C Th and the hybrid energy storage operating cost, and the optimization objective is expressed by the function

[0016] min F = C G + C B + C Th + C CP ;

[0017] The thermal power operation cost C Th is the sum of the power generation cost and the frequency regulation reserve cost, and is calculated using the following formula

[0018]

[0019] where P Th,k,t and R Th,k,t are the power generation output and the frequency regulation reserve capacity of thermal power unit k during the scheduling period t, respectively. a k and b k and c k are the quadratic term, the linear term, and the constant term coefficients of the power generation cost of thermal power unit k, respectively. c ThF,k is the operation cost of thermal power unit k providing a unit of frequency regulation reserve capacity during the operation scheduling period, and n Th is the number of thermal power units started up during the scheduling period;

[0020] The curtailment penalty C CP is linearly related to the curtailment of wind and photovoltaic power, and different penalty coefficients are set for the curtailment of wind and photovoltaic power according to the actual characteristics of the high-proportion new energy system. It is specifically calculated using the following formula:

[0021]

[0022] where c WCP and c PVCP are the penalty coefficients for unit curtailment of wind and photovoltaic power, respectively. P WC,i,t is the curtailment power of wind power i during the scheduling period t, and P PVC,j,t is the curtailment power of photovoltaic power j during the scheduling period t, and n W and n PV are the numbers of wind power generation and photovoltaic power generation, respectively.

[0023] Preferably, the constraint conditions include at least system power balance constraints, system security constraints, and operation constraints of power sources and energy storage. The system power balance constraints and system security constraints are set to meet the peak shaving and frequency regulation requirements of the high-proportion new energy system, and the operation constraints of power sources and energy storage are set according to the operation characteristics of different facilities in the high-proportion new energy system.

[0024] Preferably, the power balance constraint is as follows:

[0025]

[0026] 0 ≤ P Tr,t ≤ P Tr,max

[0027] where P W,i,t and P PV,j,t are the actual scheduling powers of wind power i and photovoltaic power j during the scheduling period t, respectively. PLd,t is the electricity load of the system during the scheduling period t, P Tr,t is the power transmitted out of the system during the scheduling period t, P Tr,max is the upper limit of the system's transmission channel capacity.

[0028] Preferably, the system's frequency regulation requirements are met by setting system security constraints for frequency. For a high-proportion new energy system, the frequency regulation reserve capacity requirement depends on the system's maximum load and the installed capacity of new energy. The system security constraints are as follows:

[0029]

[0030] where R B,t is the frequency regulation reserve capacity provided by the electrochemical energy storage during the scheduling period t, R Th,k,t is the frequency regulation reserve capacity provided by thermal power unit k during the scheduling period t, R T is the total frequency regulation reserve capacity requirement of the system, C W,i is the installed capacity of wind power i, C PV,j is the installed capacity of photovoltaic power generation j, P Ld,t is the electricity load of the system during the scheduling period t.

[0031] Preferably, the operating constraints of thermal power units consider upper and lower output limits, ramp rate constraints, and frequency regulation reserve capacity constraints; the actual dispatching power of new energy does not exceed its predicted output, and the difference is the curtailed power; the operating constraints of specific power sources include:

[0032] P Th,k,min ≤P Th,k,t ≤P Th,k,max

[0033] -ΔP Th,k,down ≤P Th,k,t+1 -P Th,k,t ≤ΔP Th,k,up

[0034] 0≤R Th,k,t ≤P Th,k,max -P Th,k,t

[0035] 0≤P W,i,t ≤P WPr,i,t

[0036] P W,i,t +P WC,i,t =P WPr,i,t

[0037] 0≤P PV,j,t ≤P PVPr,j,t

[0038] P PV,j,t +PPVC,j,t = P PVPr,j,t

[0039] where P Th,k,max , P Th,k,min are the upper and lower limits of the output of thermal power unit k respectively, P Th,k,t+1 is the power generation output of thermal power unit k at scheduling period t + 1, ΔP Th,k,up , ΔP Th,k,down are the upper limits of the upward and downward ramping rates of thermal power unit k respectively, P W,i,t , P PV,j,t are the actual scheduling powers of wind power i and photovoltaic power j at scheduling period t respectively, P WPr,i,t , P PVPr,j,t are the predicted outputs of wind power i and photovoltaic power j at scheduling period t respectively.

[0040] Preferably, the operation constraints of the energy storage consider the upper and lower limits of charge-discharge power, state of charge constraints and frequency regulation reserve constraints, and the specific forms are as follows:

[0041]

[0042] σ G,t ∈ {0, 1)

[0043]

[0044] E G,min ≤ E G,t ≤ E G,max

[0045] E G,0 = E G,T

[0046]

[0047] σ B,t ∈ {0, 1}

[0048]

[0049] E B,min ≤ E B,t ≤ E B,max

[0050] E B,0 = E B,T

[0051]

[0052] where are the upper limits of the charge and discharge powers of the gravity energy storage respectively, σ G,tis a binary variable for determining the charge / discharge state of the gravity energy storage during the scheduling period t. When it is 0, it represents charging, and when it is 1, it represents discharging, E G,t and E G,t+1 are the state of charge of the gravity energy storage at times t and t + 1 during the scheduling period, E G,0 and E G,T represent the state of charge of the gravity energy storage at the beginning and end of the scheduling period respectively, E G,max and E G,min are the upper and lower limits of the charge of the gravity energy storage respectively, are the charge and discharge efficiencies of the gravity energy storage respectively, are the upper limits of the charge and discharge power of the electrochemical energy storage respectively, σ B,t is a binary variable for determining the charge / discharge state of the electrochemical energy storage during the scheduling period t. When it is 0, it represents charging, and when it is 1, it represents discharging, E B,t and E B,t+1 are the state of charge of the electrochemical energy storage at times t and t + 1 during the scheduling period respectively, E B,0 and E B,T represent the state of charge of the electrochemical energy storage at the beginning and end of the scheduling period respectively, E B,max and E B,min are the upper and lower limits of the charge of the electrochemical energy storage respectively, are the charge and discharge efficiencies of the electrochemical energy storage respectively.

[0053] Based on the same inventive concept, the present application also discloses a hybrid energy storage scheduling system that uses the aforementioned hybrid energy storage scheduling method. The hybrid energy storage scheduling system includes:

[0054] A hybrid energy storage operation economic model construction unit that establishes a mathematical model of the operating cost of different energy storage systems participating in power regulation according to the characteristics of whether different energy storage systems participate in system peak shaving and frequency modulation;

[0055] A scheduling optimization unit that is used to consider the regulation requirements of a high-proportion new energy system and the operating characteristics of facilities in the system to set constraint conditions, and establish a hybrid energy storage scheduling optimization model for regulating a high-proportion new energy power system with the minimum sum of the total system operating cost and the penalty for abandoned electricity as the optimization goal;

[0056] A solving unit that is used to solve the hybrid energy storage scheduling optimization model to obtain the optimal scheduling plan for the hybrid energy storage to participate in power system peak shaving and frequency modulation.

[0057] Based on the same inventive concept, the present application also discloses a computer device, including a memory, a processor, and a computer program stored on the memory and executable on the processor. When the processor executes the computer program, the aforementioned hybrid energy storage scheduling method for regulating a high-proportion new energy system is implemented.

[0058] Based on the same inventive concept, the present application also discloses a storage medium, on which a computer program is stored, and when the computer program is executed by a processor, it implements the hybrid energy storage scheduling method for regulating a high-proportion new energy system as described above.

[0059] Compared with the prior art, the beneficial effects of this solution are as follows: A hybrid energy storage scheduling method for regulating a high-proportion new energy system is provided, with the sum of the minimum total system operating cost and the curtailment penalty as the optimization objective, and a "gravity-electrochemical" hybrid energy storage scheduling optimization model for peak shaving and frequency modulation of a high-proportion new energy system is established, providing a theoretical basis for hybrid energy storage scheduling and solving it based on the interior point method. By applying this method, the optimal scheduling of "gravity-electrochemical" hybrid energy storage can be achieved, and the optimal peak shaving and frequency modulation scheduling strategy can be provided, meeting the regulation requirements of a high-proportion new energy system including peak shaving and frequency modulation needs, effectively improving the new energy consumption level, verifying the effectiveness of the model through case studies, and clarifying the characteristics and advantages of this solution. Description of the Drawings

[0060] Figure 1 It is a schematic flowchart of an embodiment of this solution;

[0061] Figure 2 It is a schematic diagram of the load characteristics of a high-proportion new energy system;

[0062] Figure 3 It is a schematic diagram of the wind and light output characteristics of a high-proportion new energy system;

[0063] Figure 4 It is a schematic diagram of the charge and discharge strategy when the hybrid energy storage system includes gravity energy storage and electrochemical energy storage;

[0064] Figure 5 It is a schematic diagram of the system power transmission and wind curtailment power completed in an embodiment of this solution;

[0065] Figure 6 It is a schematic diagram of the composition of the system frequency modulation reserve capacity completed in an embodiment of this solution. Detailed Embodiments

[0066] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments.

[0067] Next, a hybrid energy storage scheduling method for regulating a high-proportion new energy system proposed according to an embodiment of the present invention will be described with reference to the drawings.

[0068] Figure 1 The disclosed embodiments include the following steps:

[0069] Step S1: Based on the characteristics of gravity energy storage and electrochemical energy storage, establish an operating economic model for "gravity - electrochemical" hybrid energy storage to quantitatively characterize the operating costs of the hybrid energy storage system participating in system peak shaving and frequency regulation.

[0070] The specific implementation process is as follows:

[0071] Gravity energy storage on the grid side mainly plays a role in peak shaving, and its operating cost C G is linearly related to the charge - discharge amount:

[0072]

[0073] In the formula, C G is the operating cost of gravity energy storage, c GE is the operating cost per unit charge - discharge amount of gravity energy storage, are the charge and discharge powers of gravity energy storage during the scheduling period t respectively, T is the total number of operating scheduling periods, and Δt is the time step of operating scheduling.

[0074] Electrochemical energy storage on the grid side can play roles in peak shaving and frequency regulation. Among them, the peak - shaving operating cost is linearly related to the charge - discharge amount, and the frequency - regulation operating cost is linearly related to the frequency - regulation reserve capacity:

[0075]

[0076] In the formula, C B is the operating cost of electrochemical energy storage, c BE is the operating cost per unit charge - discharge amount of electrochemical energy storage, c BF is the operating cost per unit frequency - regulation reserve capacity provided by electrochemical energy storage during the Δt period, R B,t are the charge - discharge power and frequency - regulation reserve capacity of electrochemical energy storage during the scheduling period t respectively.

[0077] In addition to using gravity energy storage and electrochemical energy storage, other energy storage involved in the hybrid energy storage can also use the corresponding cost functions.

[0078] Step S2: Taking the minimum of the sum of the total system operating cost and the penalty for abandoned electricity as the optimization objective, considering power balance constraints, system security constraints, and the operating constraints of power sources and energy storage, establish a "gravity - electrochemical" hybrid energy storage scheduling optimization model for peak shaving and frequency regulation of a high - proportion new - energy system;

[0079] The specific model composition is as follows:

[0080] (1) Objective function

[0081] Taking the minimum of the sum of the total system operating cost and the curtailment penalty as the optimization objective, where the total operating cost includes the operating cost of thermal power units and the operating cost of the hybrid energy storage in step S1. The specific objective function is set as follows:

[0082] min F=C G +C B +C Th +C CP

[0083] In the formula, C Th is the operating cost of thermal power units, and C CP is the curtailment penalty.

[0084] The operating cost of thermal power units consists of the power generation cost and the frequency regulation reserve operating cost:

[0085]

[0086] In the formula, T is the total number of operating scheduling periods, P Th,k,t , R Th,k,t are the power generation output and the frequency regulation reserve capacity of thermal power unit k in scheduling period t respectively, a k , b k , c k are the quadratic term, the linear term, and the constant term coefficients of the power generation cost of thermal power unit k respectively, c ThF,k is the operating cost of thermal power unit k providing a unit of frequency regulation reserve capacity within the Δt period, and n Th is the number of thermal power units in operation during the scheduling period.

[0087] The curtailment penalty is linearly related to the curtailment of wind power and photovoltaic power, and different penalty coefficients can be set for the curtailment of wind power and photovoltaic power according to the actual characteristics of the high-proportion new energy system:

[0088]

[0089] In the formula, T is the total number of operating scheduling periods, c WCP , c PVCP are the penalty coefficients for unit curtailment of wind power and photovoltaic power respectively, P WC,i,t is the curtailment power of wind power i in scheduling period t, P PVC,j,t is the curtailment power of photovoltaic power j in scheduling period t, n W , n PV are the numbers of wind power generation and photovoltaic power generation power sources respectively.

[0090] (2) Constraints

[0091] To meet the peak shaving and frequency regulation requirements of a high - proportion new - energy system, system power balance constraints and system security constraints are set accordingly. In addition, according to the operating characteristics of different facilities in the high - proportion new - energy system, power - source operating constraints and energy - storage operating constraints are set. The detailed constraint conditions are set as follows:

[0092] ① System power balance constraints:

[0093] The peak shaving scheduling of the high - proportion new - energy system is achieved by setting system power balance constraints:

[0094]

[0095] In the formula, P W,i,t and P PV,j,t are the actual scheduling powers of wind power generation i and photovoltaic power generation j during the scheduling period t, respectively. P Ld,t is the electricity load of the system during the scheduling period t, and P Tr,t is the power transmission capacity of the system to the outside during the scheduling period t.

[0096] In particular, for a high - proportion new - energy system, the transmission of surplus power needs to be considered, and a transmission - channel capacity constraint is established:

[0097] 0 ≤ P Tr,t ≤ P Tr,max

[0098] In the formula, P Tr,max is the upper limit of the system's transmission - channel capacity.

[0099] ② System security constraints:

[0100] By setting system frequency - security constraints, the frequency - regulation requirements of the high - proportion new - energy system are met. Specifically, the sum of the frequency - regulation reserve capacities provided by thermal power generation and electrochemical energy storage should meet the total frequency - regulation reserve demand of the system:

[0101]

[0102] In the formula, R B,t is the frequency - regulation reserve capacity provided by the electrochemical energy storage during the scheduling period t, R Th,k,t is the frequency - regulation reserve capacity provided by thermal - power unit k during the scheduling period t, and R T is the total frequency - regulation reserve capacity demand of the system.

[0103] In particular, in a high - proportion new - energy system, the frequency - regulation reserve capacity demand of the system depends on the system's maximum load and the installed capacity of new energy:

[0104]

[0105] In the formula, C W,iis the installed capacity of wind power generation i, C PV,j is the installed capacity of photovoltaic power generation j.

[0106] ③ New energy output constraint:

[0107] The actual dispatching power of wind and photovoltaic power generation does not exceed its predicted output, and the difference is the curtailed power:

[0108] 0 ≤ P W,i,t ≤ P WPr,i,t

[0109] P W,i,t + P W C ,i,t = P WPr,i,t

[0110] 0 ≤ P PV,j,t ≤ P PVPr,j,t

[0111] P PV,j,t + P PVC,j,t = P PVPr,j,t

[0112] In the formula, P WPr,i,t 、P PVPr,j,t are the predicted outputs of wind power generation i and photovoltaic power generation j during the dispatching period t respectively.

[0113] ④ Thermal power unit operation constraint:

[0114] Upper and lower limits of thermal power unit output constraint:

[0115] P Th,k,min ≤ P Th,k,t ≤ P Th,k,max

[0116] In the formula, P Th,k,max 、P Th,k,min are the upper and lower limits of the output of thermal power unit k respectively.

[0117] Thermal power unit ramp rate constraint:

[0118] -ΔP Th,k,down ≤ P Th,k,t+1 - P Th,k,t ≤ ΔP Th,k,up

[0119] In the formula, ΔP Th,k,up 、ΔP Th,k,down are the upper limits of the upward and downward ramp rates of thermal power unit k respectively.

[0120] Thermal power unit frequency regulation reserve capacity constraint:

[0121] 0 ≤ R Th,k,t ≤ PTh,k,max -P Th,k,t

[0122] 0 ≤ R Th,k,t ≤ P Th,k,t -P Th,k,min

[0123] ⑤ Operating constraints of gravity energy storage:

[0124] Constraints on the upper and lower limits of charge and discharge power:

[0125]

[0126] σ G,t ∈ {0, 1}

[0127] In the formula, are the upper limits of the charge and discharge power of gravity energy storage respectively, and σ G,t is a binary variable for judging the charge / discharge state of gravity energy storage during the scheduling period t. When it is 0, it represents charging, and when it is 1, it represents discharging.

[0128] Constraints on state of charge:

[0129]

[0130] E G,min ≤ E G,t ≤ E G,max

[0131] E G,0 = E G,T

[0132] In the formula, E G,t is the state of charge of gravity energy storage during the scheduling period t, and E G,max , E G,min are the upper and lower limits of the charge amount of gravity energy storage respectively, are the charge and discharge efficiencies of gravity energy storage respectively.

[0133] ⑥ Operating constraints of electrochemical energy storage:

[0134] Constraints on the upper and lower limits of charge and discharge power:

[0135]

[0136] σ B,t ∈ {0, 1}

[0137] In the formula, are the upper limits of the charge and discharge power of electrochemical energy storage respectively, and σ B,t is a binary variable for judging the charge / discharge state of electrochemical energy storage during the scheduling period t. When it is 0, it represents charging, and when it is 1, it represents discharging.

[0138] State of Charge Constraint:

[0139]

[0140] E B,min ≤E B,t ≤E B,max

[0141] E B,0 =E B,T

[0142] Wherein, E B,t is the state of charge of the electrochemical energy storage during the scheduling period t, and E B,max , E B,min are the upper and lower limits of the charge of the electrochemical energy storage respectively, are the charge and discharge efficiencies of the electrochemical energy storage respectively.

[0143] Frequency Regulation Reserve Capacity Constraint of Electrochemical Energy Storage:

[0144]

[0145] Step S3: Using the power source and load data of the high-proportion new energy system as input, solve the optimization model based on the interior point method to obtain the optimal scheduling plan for the "gravity-electrochemical" hybrid energy storage to participate in system peak shaving and frequency regulation.

[0146] Specifically, the following data of the high-proportion new energy system are used as input for the optimal scheduling of the hybrid energy storage to participate in system regulation:

[0147] The load curve of the high-proportion new energy system in this embodiment is as Figure 2 shown. The system is connected to four wind turbines with a total installed capacity of 455 MW and two photovoltaic power generations with a total installed capacity of 156 MW. The wind and light output characteristics are as Figure 3 shown. The system is connected to 2 thermal power units, and the parameter settings are shown in Table 1. It is connected to a 26 MW / 100 MWh gravity energy storage and a 100 MW / 200 MWh electrochemical energy storage, and the parameter settings are shown in Table 2. The system frequency regulation reserve capacity requirement is 5% of the maximum load + 10% of the new energy installed capacity, which is 79.2 MW in this embodiment. The system external transmission channel capacity is set to 100 MW. The curtailment penalties for wind power and photovoltaic are set at 380 yuan / MWh and 450 yuan / MWh respectively with reference to relevant policies.

[0148] Table 1 Parameter Settings of Thermal Power Units

[0149]

[0150] Table 2 Parameter Settings of Energy Storage

[0151]

[0152] The optimization model constructed in step S2 is a quadratic convex optimization, and the interior point method is preferably used for solving. Specifically, in this embodiment, programming is performed using Matlab, and the Gurobi solver is called based on the Yalmip optimization platform for solving. For the above-mentioned high-proportion new energy system, the optimization scheduling results of the hybrid energy storage are as follows:

[0153] From Figure 4 it can be seen that during the peak period of new energy output from 9:00 to 15:00 during the day, when there is a new energy consumption demand (up-regulation peak demand) in the system, the gravity energy storage charges at a maximum power of 26 MW for a long time, while the charging power of the electrochemical energy storage fluctuates with the power output of the power source and the electrical load. Figure 5 shows the outgoing power and the curtailed power of the system when the hybrid energy storage system participates in system regulation. In this embodiment, there is no curtailment of light throughout the scheduling period, and the curtailment of electricity is only the curtailment of wind. In terms of frequency regulation, the demand for the frequency regulation reserve capacity of the system is mainly met by thermal power units, and a small amount is met by electrochemical energy storage. For the specific composition example of the frequency regulation reserve capacity, see Figure 6 . Under the optimal scheduling strategy obtained in this embodiment, compared with participating in system frequency regulation, more of the capacity of the energy storage is used to participate in system peak shaving to improve the new energy consumption level. Table 3 shows the composition of the objective function in the optimization results, that is, the daily operating cost of the system and the composition of the curtailment penalty under the optimal scheduling strategy. The results show that under the curtailment penalty level set according to the current policy, the scheduling strategy of the energy storage participating in the regulation of the high-proportion new energy system tends to give priority to meeting the new energy consumption demand to minimize the curtailment penalty as much as possible.

[0154] Table 3 Composition of the objective function of the optimization results Unit: yuan

[0155]

[0156] According to a hybrid energy storage scheduling method for regulating a high-proportion new energy system proposed in an embodiment of the present invention, through the optimal scheduling of "gravity-electrochemical" hybrid energy storage participating in system peak shaving and frequency regulation, the regulation requirements of the high-proportion new energy system can be met, and the new energy consumption level can be improved.

[0157] Based on the same inventive concept, the present application also discloses a hybrid energy storage scheduling system for regulating a high-proportion new energy system, which uses the aforementioned hybrid energy storage scheduling method for regulating a high-proportion new energy system. The hybrid energy storage scheduling system includes:

[0158] A hybrid energy storage operation economic model construction unit, which establishes a mathematical model of the operating cost of different energy storage systems participating in power regulation according to the characteristics of whether different energy storage systems participate in system peak shaving and frequency regulation;

[0159] A scheduling optimization unit is configured to set constraint conditions by considering the regulation requirements of a high-proportion new energy system and the operating characteristics of facilities within the system, and establish a hybrid energy storage scheduling optimization model for the regulation of a high-proportion new energy power system with the minimum of the sum of the total system operating cost and the penalty for curtailed electricity as the optimization objective;

[0160] A solving unit is configured to solve the hybrid energy storage scheduling optimization model to obtain an optimal scheduling plan for the hybrid energy storage to participate in the peak shaving and frequency modulation of the power system.

[0161] Based on the same inventive concept, the present application also discloses a computer device, including a memory, a processor, and a computer program stored on the memory and executable on the processor. When the processor executes the computer program, the foregoing hybrid energy storage scheduling method for the regulation of a high-proportion new energy system is implemented.

[0162] Based on the same inventive concept, the present application also discloses a storage medium, on which a computer program is stored. When the computer program is executed by a processor, the foregoing hybrid energy storage scheduling method for the regulation of a high-proportion new energy system is implemented. The storage medium can be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as static random access memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic memory, flash memory, a magnetic disk, or an optical disc.

[0163] In the description of the present invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise specifically defined. In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples", etc. means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0164] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention.

Claims

1. A hybrid energy storage scheduling method, characterized in that Use the following steps: S1. Establish an operation economic model of hybrid energy storage, and quantitatively characterize the operation cost of the hybrid energy storage system participating in the power system regulation. The hybrid energy storage system includes at least gravity energy storage and electrochemical energy storage. The operation cost of the hybrid energy storage system participating in the power system regulation includes at least the operation cost C of the gravity energy storage participating in the power system regulation. G and the operating cost of electrochemical energy storage participating in power system regulation C B , the gravity energy storage on the grid side participates in the peak load regulation of the system, and the operating cost of the gravity energy storage participating in the power system regulation is C G It is a linear function of the charge and discharge capacity, and is calculated using the following formula: Among them, c GE is the operating cost of gravity energy storage per unit charge and discharge capacity, are the charging and discharging power of gravity energy storage in the dispatching period t, T is the total number of operation dispatching periods, Δt is the time step of operation dispatching; the grid-side electrochemical energy storage participates in the system peak regulation and frequency regulation, and the operating cost C of the electrochemical energy storage participating in the power system regulation B It is a linear function of the charge and discharge capacity and the frequency regulation reserve capacity, and is calculated using the following formula: Among them, c BE is the operating cost of electrochemical energy storage per unit charge and discharge capacity, c BF The operating cost of providing unit frequency regulation reserve capacity for electrochemical energy storage during the Δt period, R B,t are the charging and discharging power and frequency regulation reserve capacity of electrochemical energy storage in the dispatching period t respectively; S2, based on the total system operating cost and the power abandonment penalty C CP The minimum sum F is taken as the optimization goal, and the constraints are set by considering the regulation demand of the high-proportion renewable energy system and the operating characteristics of the facilities in the system, and a hybrid energy storage dispatch optimization model for the regulation of the high-proportion renewable energy power system is established; S3, using the power supply and load data of the high-proportion new energy system as input, solves the hybrid energy storage scheduling optimization model based on the interior point method, and obtains the optimal scheduling plan for hybrid energy storage to participate in the peak and frequency regulation of the power system.

2. The hybrid energy storage scheduling method according to claim 1, characterized in that: The total system operating cost and the power abandonment penalty C CP The sum F is the minimum, which is the total system operating cost in the optimization target, including at least the thermal power operating cost C Th With the hybrid energy storage operation cost, the optimization objective uses the functional expression: min F=C G +C B +C Th +C CP ; The thermal power operation cost C Th is the sum of power generation cost and frequency regulation reserve cost, calculated using the following formula Among them, P Th,k,t , R Th,k,t are the power generation output and frequency regulation reserve capacity of thermal power unit k in the dispatching period t, a k 、b k 、c k are the coefficients of the quadratic term, linear term and constant term of the power generation cost of thermal power unit k, c ThF,k The operating cost of providing unit frequency regulation reserve capacity for thermal power unit k during the operation and dispatch period, n Th The number of thermal power units started during the dispatch period; The power abandonment penalty C CP It is linearly related to the amount of wind and solar power abandoned, and different penalty coefficients are set for wind and solar power abandoned according to the actual characteristics of the high-proportion new energy system. The specific calculation is based on the following formula: Among them, c WCP 、c PVCP are the penalty coefficients for unit wind and photovoltaic power abandonment, P WC,i,t is the abandoned wind power of wind power generation i in the dispatching period t, P PVC,j,t is the abandoned power of photovoltaic power generation j in the scheduling period t, n W 、n PV are the amounts of wind power and photovoltaic power, respectively.

3. The hybrid energy storage scheduling method according to claim 2, characterized in that: The constraints include at least system power balance constraints, system safety constraints, and power supply and energy storage operation constraints. The system power balance constraints and system safety constraints are set to meet the peak load and frequency regulation requirements of the high-proportion new energy system. The power supply and energy storage operation constraints are set according to the operating characteristics of different facilities in the high-proportion new energy system.

4. The hybrid energy storage scheduling method according to claim 3 is characterized in that: The power balance constraints are as follows: 0≤P Tr,t ≤P Tr,max Among them, P W,i,t and P PV,j,t are the actual dispatching power of wind power generation i and photovoltaic power generation j in dispatching period t, P Ld,t is the power load of the system in the dispatching period t, P Tr,t is the power transmission power of the system in the dispatching period t, P Tr,max It is the upper limit of the system outbound channel capacity.

5. The hybrid energy storage scheduling method according to claim 3 is characterized in that The frequency regulation requirements of the system are met by setting the system safety constraints of the frequency. For a system with a high proportion of new energy, the frequency regulation reserve capacity requirement depends on the maximum load of the system and the installed capacity of new energy. The system safety constraints are as follows: Among them, R B,t The frequency regulation reserve capacity provided by electrochemical energy storage during the dispatch period t, R Th,k,t The frequency regulation reserve capacity provided by thermal power unit k during dispatch period t, R T is the total frequency regulation reserve capacity requirement of the system, C W,i is the installed capacity of wind power generation i, C PV,j is the installed capacity of photovoltaic power generation j, R Ld,t is the power load of the system in the scheduling period t.

6. The hybrid energy storage scheduling method according to claim 3 is characterized in that The operation constraints of thermal power units take into account the upper and lower limits of output, ramp rate constraints, and frequency regulation reserve capacity constraints; the actual dispatch power of new energy does not exceed its predicted output, and the difference is the abandoned power; the specific operation constraints of power sources include: P Th,k,min ≤P Th,k,t ≤P Th,k,max -ΔP Th,k,down ≤P Th,k,t+1 -P Th,k,t ≤ΔP Th,k,up 0≤R Th,k,t ≤P Th,k,max -P Th,k,t 0≤P W,i,t ≤P WPr,i,t P W,i,t +P WC,i,t =P WPr,i,t 0≤P PV,j,t ≤P PVPr,j,t P PV,j,t +P PVC,j,t =P PVPr,j,t Among them, P Th,k,max , P Th,k,min are the upper and lower limits of the output of thermal power unit k, P Th,k,t+1 is the power output of thermal power unit k in the dispatch period t+1, ΔP Th,k,up , ΔP Th,k,down are the upper and lower ramp rate limits of thermal power unit k, respectively, W,i,t , P PV,j,t are the actual dispatching power of wind power generation i and photovoltaic power generation j in dispatching period t, P WPr,i,t , P PVPr,j,t They are the predicted outputs of wind power generation i and photovoltaic power generation j in the scheduling period t respectively.

7. The hybrid energy storage scheduling method according to claim 3 is characterized in that The energy storage operation constraints take into account the upper and lower limits of charge and discharge power, state of charge constraints, and frequency regulation and standby constraints. The specific forms are as follows: s G,t ∈{0,1} AND G,min ≤E G,t ≤E G,max AND G,0 =And G,T s B,t ∈{0,1} AND B,min ≤E B,t ≤E B,max AND B,0 =And B,T in, are the upper limits of the charging and discharging power of gravity energy storage, σ G,t It is a binary variable to judge the charging / discharging state of gravity energy storage in the scheduling period t. When it is 0, it represents charging, and when it is 1, it represents discharging. G,t 、E G,t+1 is the charge state of the gravity energy storage at the dispatching period t and t+1, E G,0 、E G,T They represent the charge state of the gravity energy storage at the beginning and end of the dispatching period, E G,max 、E G,min are the upper and lower limits of gravity energy storage charge, are the charging and discharging efficiency of gravity energy storage, are the upper limits of charge and discharge power of electrochemical energy storage, σ B,t It is a binary variable for determining the charge / discharge state of electrochemical energy storage during the scheduling period t. When it is 0, it represents charging, and when it is 1, it represents discharging. B,t 、E B,t+1 are the charge states of the electrochemical energy storage at the dispatching period t and t+1, E B,0 、E B,T They represent the charge state of the electrochemical energy storage at the beginning and end of the dispatch cycle, E B,max 、E B,min are the upper and lower limits of electrochemical energy storage charge, respectively. are the charging and discharging efficiency of electrochemical energy storage, respectively.

8. A hybrid energy storage dispatching system, characterized in that: Using the hybrid energy storage dispatching method for regulating a high-proportion new energy system according to any one of claims 1 to 7, the hybrid energy storage dispatching system comprises: The hybrid energy storage operation economic model building unit establishes the operation cost mathematical models of different energy storage systems participating in power regulation according to the characteristics of whether different energy storage systems participate in system peak regulation and frequency regulation; The dispatch optimization unit is used to consider the regulation requirements of the high-proportion renewable energy system and the operating characteristics of the facilities in the system to set constraints, and to minimize the sum of the total operating cost of the system and the power abandonment penalty, and to establish a hybrid energy storage dispatch optimization model for the regulation of the high-proportion renewable energy power system; The solving unit is used to solve the hybrid energy storage scheduling optimization model to obtain the optimal scheduling plan for hybrid energy storage to participate in the peak and frequency regulation of the power system.

9. A computer device comprising a memory, a processor and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, it implements the hybrid energy storage scheduling method for regulating a high-proportion new energy system as described in any one of claims 1-7.

10. A storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, a hybrid energy storage scheduling method for regulating a high-proportion new energy system is implemented as described in any one of claims 1 to 7.

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