Virtual power plant economic dispatching system and method based on distributed power generation

Abstract

The invention discloses a virtual power plant economic dispatching system based on distributed power generation. The system comprises a model objective function construction module which constructs an objective function for maximizing the economic benefit of a virtual power plant within a set time period; the output planning module obtains virtual power plant planned output based on distributed power generation under the corresponding condition; the operation constraint module constructs the operation constraint of the virtual power plant, and solves the model to obtain the power output of each distributed generator set; the energy storage control module is used for compensating the output deviation of the virtual power plant through combined operation of pumped storage hydroelectric generation and an energy storage battery; and the economic dispatching operation module obtains an optimized dispatching power generation plan of the future virtual power plant in each time period according to the distributed future power generation curve of the uncontrollable power supply, the time-of-use electricity price and the power generation cost. The operation economic benefits of the virtual power plant are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of virtual power plant dispatching, and in particular to a virtual power plant economic dispatching system and method based on distributed power generation. Background Art

[0002] At present, China's power industry is facing the impact of large-scale grid connection of new energy. In order to solve a series of impacts caused by the integration of distributed generators such as wind and solar energy into the power grid, experts and scholars suggest that distributed power generation of a certain scale be built into a virtual power plant. Virtual power plants can effectively integrate a large number of different distributed power generation and user loads, reduce the output power fluctuations of new energy, and improve the reliability of user power supply. Virtual power plants will not change the grid connection mode of each distributed energy source, but through the technical aggregation of various types of distributed resources, such as distributed generation, energy storage systems and controllable loads, to achieve effective aggregation and management of distributed generation, and have similar operating functions to traditional power plants, participating in power market transactions and system scheduling. The core of the virtual power plant is the control and coordination center, which has functions such as power generation management and distributed generation power forecasting.

[0003] Virtual power plants are usually composed of large-scale renewable energy and controllable power sources. Controllable power sources are traditional power sources or energy storage systems. The established optimization model is optimized through different optimization methods to maximize the benefits or minimize the costs of virtual power plants. On the one hand, few studies have considered the impact of time-of-use electricity prices on virtual power plants, while time-of-use electricity prices are widely used in China as price-based demand response. Therefore, for the power generation side of virtual power plants, their operating strategies should adapt to the operating environment of the distribution network, participate in peak-shaving and valley-filling by formulating reasonable operating strategies, reduce power generation costs, and thus obtain greater economic benefits. On the other hand, controllable power sources are traditional power sources or energy storage systems, and when large-scale new energy power is connected to the grid, energy storage systems such as pumped storage and energy storage batteries have limitations when operating alone. Therefore, it is of great significance to study the economic dispatch modeling method of virtual power plants considering distributed generation. Summary of the invention

[0004] The purpose of the present invention is to provide a virtual power plant economic dispatching system and method based on distributed power generation. The present invention reduces the impact of the uncertainty of new energy output power on the safety of the power grid and improves the power supply reliability, thereby maximizing the economic benefits of the virtual power plant.

[0005] To achieve this purpose, the virtual power plant economic dispatch system based on distributed power generation designed by the present invention includes:

[0006] The model objective function construction module is used to construct an objective function that maximizes the economic benefits of the virtual power plant within a set time period by considering the management cost of distributed energy resources, the fuel cost of gas turbines, the penalty for deviation from the output plan, and the penalty for abandoning wind power generation and photovoltaic power generation;

[0007] The output planning module is used to compare the electricity purchase price in a set time period with the unit fuel cost of gas turbine power generation, and obtain the planned output of the virtual power plant based on distributed power generation under the corresponding circumstances;

[0008] The operation constraint module is used to construct the operation constraints of the virtual power plant. Through the objective function and the operation constraints, the economic dispatch model of the virtual power plant is constructed, and the economic dispatch model of the virtual power plant is solved to obtain the power output of each distributed generator set;

[0009] The energy storage control module is used to jointly operate pumped storage hydropower generation and energy storage batteries to compensate for the output deviation of the virtual power plant, so that the actual output of the virtual power plant tracks the planned output of the virtual power plant;

[0010] The economic dispatch operation module is used to calculate the power generation cost of each distributed generator set according to the power output of each distributed generator set multiplied by the time-of-use electricity price in the distribution network, and obtain the distributed future power generation curve of the uncontrollable power source according to the power output of each distributed generator set. When the actual output of the virtual power plant tracks the planned output of the virtual power plant, the optimized dispatching power generation plan for each time period of the future virtual power plant is obtained according to the distributed future power generation curve of the uncontrollable power source, the time-of-use electricity price in the distribution network and the power generation cost of each distributed generator set.

[0011] Beneficial effects of the present invention:

[0012] By constructing a virtual power plant composed of large-scale renewable energy and controllable energy, the present invention can reduce the impact of the uncertainty of new energy output power on the security of the power grid and improve the reliability of power supply; it can enable distributed power sources to effectively participate in peak-loading and valley-filling, thereby obtaining greater benefits; through the virtual power plant economic dispatch model, the virtual power plant can ensure that the power sales revenue is maximized under the premise of meeting the power grid demand and constraints, including making reasonable quotations in the power market, selecting the best trading period and optimizing the number of power transactions; the virtual power plant economic dispatch model can help the virtual power plant reasonably arrange the operation and maintenance plans of each distributed energy source, thereby reducing the overall operating cost; the economic dispatch model can comprehensively consider the characteristics of each distributed energy source and the power grid demand, and realize the optimal allocation and utilization of resources; when a large amount of uncontrollable new energy is integrated into the power grid, by equipping pumped storage and energy storage systems, their limitations can be balanced, so that the virtual power plant can obtain better economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a structural schematic diagram of the present invention;

[0014] Figure 2 is a flow chart of the present invention;

[0015] Figure 3 It is a strategy execution diagram of the present invention;

[0016] Figure 4 The power output curve diagram of the gas turbine of the present invention;

[0017] Figure 5 It is the energy storage state diagram of the pumped storage and energy storage battery of the present invention;

[0018] Figure 6 The virtual power plant revenue curve diagram of the present invention;

[0019] Figure 7 A comparison diagram of the revenue curves of the energy storage system and the system without energy storage of the present invention; DETAILED DESCRIPTION

[0020] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments:

[0021] Example 1

[0022] A virtual power plant economic dispatch system based on distributed generation, such as Figure 1 As shown, it includes:

[0023] The model objective function construction module is used to construct an objective function that maximizes the economic benefits of the virtual power plant within a set time period by considering the management cost of distributed energy, the fuel cost of gas turbines, the penalty for deviation from the output plan, and the penalty for abandoning wind power generation and photovoltaic power generation. This design is used to combine the obtained objective function with the following operating constraints to calculate the power output of each distributed generator set;

[0024] The output planning module is used to compare the electricity purchase price in the set time period with the unit fuel cost of gas turbine power generation, and obtain the planned output of the virtual power plant based on distributed power generation under the corresponding circumstances. This design is used to obtain the planned output of the virtual power plant so that the actual output of the virtual power plant tracks the planned output of the virtual power plant;

[0025] The operation constraint module is used to construct the operation constraints of the virtual power plant. Through the objective function and the operation constraints, the economic dispatch model of the virtual power plant is constructed, and the economic dispatch model of the virtual power plant is solved to obtain the power output of each distributed generator set. This design is used to combine with the above objective function to calculate the power output of each distributed generator set;

[0026] The energy storage control module is used to jointly operate pumped storage hydropower generation and energy storage batteries to compensate for the output deviation of the virtual power plant, so that the actual output of the virtual power plant tracks the planned output of the virtual power plant. This design is used to compensate for the deviation between the planned output and the actual output of the virtual power plant;

[0027] The economic dispatch operation module is used to calculate the power generation cost of each distributed generator set according to the power output of each distributed generator set multiplied by the time-of-use electricity price in the distribution network, and obtain the distributed future power generation curve of the uncontrollable power source according to the power output of each distributed generator set (build a virtual power plant economic dispatch model, and solve the virtual power plant economic dispatch model to obtain the power output of each distributed generator set. The power output obtained is the distributed future power generation curve). When the actual output of the virtual power plant tracks the planned output of the virtual power plant, the distributed future power generation curve of the uncontrollable power source, the time-of-use electricity price in the distribution network and each distributed generator set are used. The optimal dispatching power generation plan of the virtual power plant in each time period in the future is obtained based on the power generation cost of the virtual power plant (by comparing the distributed power generation cost and the time-of-use electricity price of the distribution network: if the distributed power generation cost is greater than the time-of-use electricity price of the distribution network, and the actual output of the uncontrollable distributed power generation is greater than the planned output, the operation of abandoning the wind power generation power and the photovoltaic power generation power is executed; if the distributed power generation cost is less than the time-of-use electricity price of the distribution network, and the actual output of the uncontrollable distributed power generation is greater than the planned output, the operation of selling the excess power to the distribution network is executed; if the actual output of the uncontrollable distributed power generation is less than the planned output, the insufficient electricity is purchased from the distribution network). This design is used to maximize the economic benefits of the operation of the virtual power plant.

[0028] In the above technical solution, the distributed generator set includes wind power generation, photovoltaic power generation, gas turbines, pumped storage and batteries.

[0029] In the above technical solution, the specific construction process of the objective function is:

[0030] As shown in equation (1):

[0031]

[0032] in:

[0033]

[0034] Among them, t is the time series, the time interval of each time period is 15 minutes, t = 1, 2, .., 96; is the net profit of the virtual power plant in time period t; is the revenue of the virtual power plant in time period t, X1 t is the electricity price for time period t, They are the power outputs of wind power generation, photovoltaic power generation, gas turbines, pumped storage and batteries, and the charging power of pumped storage and batteries in time period t; is the operation and management cost of the virtual power plant in time period t; is the operation management coefficient of wind power generation, photovoltaic power generation, gas turbine, pumped storage and battery; are the energy consumption costs of the virtual power plant in time period t; X G is the unit fuel cost of gas turbine power generation; is the penalty cost of the virtual power plant in period t; X2 t is the electricity purchase price in period t; P t is the planned output of the virtual power plant in period t; is the penalty cost of giving up wind power and photovoltaic power; X AP is the unit cost of forgoing wind power and photovoltaic power.

[0035] In the above technical solution, the virtual power plant output plan is calculated according to the following equation:

[0036]

[0037] Among them, P st is the planned output of uncontrollable distributed generation in time period t, is the maximum output of the gas turbine, X2 t is the electricity purchase price in period t, X G is the unit fuel cost of gas turbine power generation.

[0038] In the above technical solution, the specific construction process of the operation constraints of the virtual power plant is:

[0039] Virtual power plants must meet power balance constraints as follows:

[0040]

[0041] Where: is the output deviation of the virtual power plant in time period t;

[0042] The power constraints of the controllable power supply are as follows:

[0043]

[0044] Where: and are the upper and lower limits of gas turbine power, respectively;

[0045] Pumped storage capacity and generation / pumping limits are as follows:

[0046] R min< R t <R max (10)

[0047]

[0048] Where: R min and R max is the lower and upper limits of the reservoir capacity; R t is the water storage capacity of the reservoir in period t; and is the state variable of power generation and water pumping, with a value of 0 or 1; and is the power generation and pumping power in period t; α and β are the power generation efficiency and pumping efficiency respectively; and are the lower and upper limits of power generation, respectively; and are the lower and upper limits of the pumping power, respectively;

[0049] The energy and charge / discharge constraints of the energy storage battery are as follows:

[0050]

[0051] Where: and are the lower and upper limits of the energy storage battery capacity respectively; is the energy level of the battery in period t; and It is the state variable of charging and discharging, with a value of 0 or 1; and are the charging and discharging powers in period t, respectively; η and λ are the charging and discharging efficiencies, respectively; and They are the lower and upper limits of the charging power respectively; and are the lower limit and upper limit of the discharge power respectively; the above design is used to combine with the above objective function to calculate the power output of each distributed generator set.

[0052] In the above technical solution, the power output of the gas turbine in the distributed generator set is obtained in the following manner:

[0053] If the cost of generating electricity from a gas turbine is higher than the time-of-use electricity price in the distribution grid, the gas turbine will shut down;

[0054] If the power generation cost of the gas turbine is lower than the time-of-use electricity price in the distribution network, the gas turbine will generate electricity, and the gas turbine power output at this time will be calculated according to the virtual power plant economic dispatch model;

[0055] The power generation cost of the gas turbine is lower than the time-of-use electricity price in the distribution network. When there is uncontrollable distributed power generation and the energy storage system cannot fully absorb the excess power, the gas turbine obtains the corresponding gas turbine power output based on demand in combination with the virtual power plant economic dispatch model. The above design is used to reduce the use cost of the gas turbine, because gas turbine power generation is a traditional energy source, which will increase the penalty for abandoning wind power generation and photovoltaic power generation, which can also improve the operating economic benefits of the virtual power plant.

[0056] In the above technical solution, the specific process of the virtual power plant compensating the output deviation of the virtual power plant by the joint operation of pumped storage hydropower and energy storage batteries is as follows: if the output deviation of the virtual power plant is greater than 0, indicating that the uncontrollable distributed power generation is insufficient, the virtual power plant energy storage system will generate electricity; if the energy storage system is insufficient, the virtual power plant will purchase electricity from the distribution network to meet its output plan (① if the output deviation is greater than 0 and less than the first preset value, the energy storage battery will generate electricity; ② if the output deviation is greater than 0 and greater than the first preset value, and exceeds the minimum output of the turbine, the pumped storage hydropower and the energy storage battery will jointly operate to generate electricity);

[0057] If the output deviation is less than 0, indicating that the power generation of uncontrollable distributed generation exceeds the planned power generation, the energy storage system in the virtual power plant will store energy (① If the output deviation is less than zero and greater than the second preset value (negative value), the energy storage battery will store energy; ② If the output deviation is less than zero and less than the second preset value (negative value), and exceeds the pumping power of the water pump, the pumped storage hydropower and the energy storage battery will jointly store energy);

[0058] Pumped storage hydropower generation and energy storage batteries operate together to compensate for output deviations, so that the actual virtual power plant output can track the planned output; pumped storage can purchase electricity and store energy during the low electricity price period, and sell electricity during the peak electricity price period, which can achieve economic benefits and play a certain role in peak load shifting;

[0059] The above design is used to compensate for the deviation between the planned output and actual output of the virtual power plant.

[0060] In the above technical solution, the specific process of obtaining the optimal dispatching power generation plan of the future virtual power plant in each time period is as follows:

[0061] The virtual power plant obtains the power output of each distributed generator set by solving the virtual power plant economic dispatch model, predicts the future power generation of uncontrollable distributed power generation, and obtains the output curve of distributed power generation of uncontrollable power sources in future interval time periods;

[0062] The virtual power plant obtains the future power generation plan of the virtual power plant by comprehensively considering the distributed future power generation curve of the uncontrollable power source, the time-of-use electricity price in the distribution network, and the power generation cost of each distributed power generation unit;

[0063] After considering the operation strategy of the virtual power plant based on time-of-use electricity prices, the future real-time optimization scheduling plan is obtained according to the future power generation plan of the virtual power plant, and the future power generation plan of the virtual power plant is submitted to the distribution network;

[0064] The distribution network arranges the output of the virtual power plant and other generating units in the region according to the future power generation plan of the virtual power plant;

[0065] The above design is used to maximize the economic benefits of virtual power plant operation.

[0066] Example 2

[0067] A method for economic dispatch modeling of virtual power plants based on distributed generation, such as Figure 2 As shown, an objective function is constructed to maximize the economic benefits of the virtual power plant within a set time period; the planned output of the virtual power plant based on distributed power generation under corresponding circumstances is obtained; the operation constraints of the virtual power plant are constructed, and the model is solved to obtain the power output of each distributed generator set; the working state of the gas turbine is controlled; pumped-storage hydropower generation and energy storage batteries are jointly operated to compensate for the output deviation of the virtual power plant, so that the actual output of the virtual power plant tracks the planned output; the optimal scheduling power generation plan of the future virtual power plant in each time period is obtained according to the uncontrollable distributed future power generation curve, time-of-use electricity price and power generation cost.

[0068] The specific method of virtual power plant economic dispatch modeling includes the following steps:

[0069] By considering the management cost of distributed energy resources, the fuel cost of gas turbines, the penalty for deviation from the output plan, and the penalty for abandoning wind power generation and photovoltaic power generation, an objective function is constructed to maximize the economic benefits of the virtual power plant within a set time period.

[0070] Compare the electricity purchase price in a set time period with the unit fuel cost of gas turbine power generation, and obtain the planned output of the virtual power plant based on distributed power generation under the corresponding circumstances;

[0071] Constructing the operation constraints of the virtual power plant, constructing the economic dispatch model of the virtual power plant through the objective function and the operation constraints, and solving the economic dispatch model of the virtual power plant to obtain the power output of each distributed power generation unit;

[0072] Combine pumped storage hydroelectric power generation and energy storage batteries to compensate for the output deviation of the virtual power plant, so that the actual output of the virtual power plant tracks the planned output of the virtual power plant;

[0073] The power generation cost of each distributed generator set is calculated by multiplying the power output of each distributed generator set by the time-of-use electricity price in the distribution network. The distributed future power generation curve of the uncontrollable power source is obtained according to the power output of each distributed generator set. When the actual output of the virtual power plant tracks the planned output of the virtual power plant, the optimized scheduling power generation plan for each time period of the future virtual power plant is obtained according to the distributed future power generation curve of the uncontrollable power source, the time-of-use electricity price in the distribution network and the power generation cost of each distributed generator set.

[0074] Example 3

[0075] A virtual power plant economic dispatch system based on distributed generation, such as Figure 3 , Figure 4 , Figure 5 , Figure 6 and Figure 7 As shown, it includes:

[0076] like Figure 3 As shown in the figure, the economic dispatch operation strategy of the virtual power plant based on distributed generation is as follows:

[0077] The virtual power plant obtains the power output of each distributed generator set by solving the virtual power plant economic dispatch model, predicts the future power generation of uncontrollable distributed power generation, and obtains the output curve of distributed power generation of uncontrollable power sources in future interval time periods;

[0078] The virtual power plant obtains the future power generation plan of the virtual power plant by comprehensively considering the distributed future power generation curve of the uncontrollable power source, the time-of-use electricity price in the distribution network, and the power generation cost of each distributed power generation unit;

[0079] After considering the operation strategy of the virtual power plant based on time-of-use electricity prices, the future real-time optimization scheduling plan is obtained according to the future power generation plan of the virtual power plant, and the future power generation plan of the virtual power plant is submitted to the distribution network;

[0080] The distribution network arranges the output of the virtual power plant and other generating units in the region according to the future power generation plan of the virtual power plant;

[0081] like Figure 4 As shown in the figure, during the periods 0-28 and 93-96 (23:00 to 7:00), the cost of power generation from the gas turbine is higher than the cost of purchasing electricity from the power grid. It is recommended to shut down the gas turbine during these time periods, while maintaining normal operation according to the operation strategy of other time periods. By designing the operation strategy of the controllable power source, the virtual power plant can adapt to the time-varying electricity prices in the power grid and obtain better economic benefits.

[0082] like Figure 5As shown, pumped storage is used to store energy during the low-price period (0-28 and 93-96) and compensate for the deviation during the flat-peak period (29-92); it also participates in peak-pricing period peak load regulation; energy storage batteries can compensate for deviations in all time periods; at the same time, the gas turbine is shut down during the low-price period (0-28, 93-96), so only the energy storage battery is running, which leads to a larger output deviation; during the normal price period (29-92), the gas turbine generates electricity, the virtual power plant is provided by renewable energy and gas turbines, and pumped storage and energy storage batteries are operated together, resulting in a smaller output deviation;

[0083] like Figure 6 As shown in the figure, in the low price period (0-28, 93-96), pumped storage filled the reservoir, and the net income decreased due to the need to pay more penalty costs (here the penalty costs refer to the penalty costs caused by giving up wind power generation and photovoltaic power generation); in the normal price period (29-92), especially in the high price period (41-60 and 73-84), the virtual power plant obtained higher net income; it was calculated that the penalty cost paid by the virtual power plant to the distribution network was 2.075×10 5 The net benefit of the virtual power plant after participating in peak load regulation and water storage is 3.401×10 7 Compare Figure 6 The total net income of the combined operation of the two is 3.9503×10 higher than that of the non-storage system. 6 yuan; comparison Figure 7 The total net income of the combined operation of the two is 3.9503×10 higher than that of the non-storage system. 6 Yuan;

[0084] By considering the complementarity of pumped storage and energy storage batteries, it is found that they can complement each other's limitations and work together to bring better benefits to the virtual power plant; pumped storage can participate in peak regulation and water storage, as well as compensate for large output deviations, while energy storage batteries can compensate for small output deviations.

[0085] Example 4

[0086] A computer program product includes a computer program, characterized in that when the computer program is executed by a processor, the steps of the method described in Example 2 are implemented.

[0087] The contents not described in detail in this specification belong to the prior art known to professional and technical personnel in this field.

Claims

1. A virtual power plant economic dispatch system based on distributed power generation, characterized in that: It includes: The model objective function construction module is used to construct an objective function that maximizes the economic benefits of the virtual power plant within a set time period by considering the management cost of distributed energy resources, the fuel cost of gas turbines, the penalty for deviation from the output plan, and the penalty for abandoning wind power generation and photovoltaic power generation; The output planning module is used to compare the electricity purchase price in a set time period with the unit fuel cost of gas turbine power generation, and obtain the planned output of the virtual power plant based on distributed power generation under the corresponding circumstances; The operation constraint module is used to construct the operation constraints of the virtual power plant. Through the objective function and the operation constraints, the economic dispatch model of the virtual power plant is constructed, and the economic dispatch model of the virtual power plant is solved to obtain the power output of each distributed generator set; The energy storage control module is used to jointly operate pumped storage hydropower generation and energy storage batteries to compensate for the output deviation of the virtual power plant, so that the actual output of the virtual power plant tracks the planned output of the virtual power plant; The economic dispatch operation module is used to calculate the power generation cost of each distributed generator set according to the power output of each distributed generator set multiplied by the time-of-use electricity price in the distribution network, and obtain the distributed future power generation curve of the uncontrollable power source according to the power output of each distributed generator set. When the actual output of the virtual power plant tracks the planned output of the virtual power plant, the optimized dispatching power generation plan for each time period of the future virtual power plant is obtained according to the distributed future power generation curve of the uncontrollable power source, the time-of-use electricity price in the distribution network and the power generation cost of each distributed generator set.

2. The virtual power plant economic dispatch system based on distributed power generation according to claim 1 is characterized by: The distributed generator set includes wind power generation, photovoltaic power generation, gas turbines, pumped storage and batteries.

3. The virtual power plant economic dispatch system based on distributed power generation according to claim 1 is characterized by: The specific construction process of the objective function is: As shown in equation (1): in: Where t is the time series; is the net profit of the virtual power plant in time period t; is the revenue of the virtual power plant in time period t, X1 t is the electricity price for time period t, They are the power outputs of wind power generation, photovoltaic power generation, gas turbines, pumped storage and batteries, and the charging power of pumped storage and batteries in time period t; is the operation and management cost of the virtual power plant in time period t; is the operation management coefficient of wind power generation, photovoltaic power generation, gas turbine, pumped storage and battery; are the energy consumption costs of the virtual power plant in time period t; X G is the unit fuel cost of gas turbine power generation; is the penalty cost of the virtual power plant in period t; is the electricity purchase price in period t; P t is the planned output of the virtual power plant in period t; is the penalty cost of giving up wind power and photovoltaic power; X AP is the unit cost of forgoing wind power and photovoltaic power.

4. The virtual power plant economic dispatch system based on distributed power generation according to claim 1 is characterized by: The planned output of the virtual power plant is calculated according to the following equation: Among them, P st is the planned output of uncontrollable distributed generation in time period t, is the maximum output of the gas turbine, is the electricity purchase price in period t, X G is the unit fuel cost of gas turbine electricity generation.

5. The virtual power plant economic dispatch system based on distributed power generation according to claim 1 is characterized by: The specific construction process of the operation constraints of the virtual power plant is as follows: Virtual power plants must meet power balance constraints as follows: Where: is the output deviation of the virtual power plant in time period t; The power constraints of the controllable power supply are as follows: Where: and are the upper and lower limits of gas turbine power, respectively; Pumped storage capacity and generation / pumping limits are as follows: R min < R t <R max (10) Where: R min and R max are the lower and upper limits of reservoir capacity; R t is the water storage capacity of the reservoir in period t; and is the state variable of power generation and water pumping, with a value of 0 or 1; and are the power generation and pumping power in period t; α and β are the power generation efficiency and pumping efficiency respectively; and are the lower and upper limits of power generation, respectively; and are the lower and upper limits of the pumping power, respectively; The energy and charge / discharge constraints of the energy storage battery are as follows: Where: and are the lower and upper limits of the energy storage battery capacity respectively; is the energy level of the battery in period t; and It is the state variable of charging and discharging, with a value of 0 or 1; and are the charging and discharging powers in period t, respectively; η and λ are the charging and discharging efficiencies, respectively; and They are the lower and upper limits of the charging power respectively; and are the lower and upper limits of the discharge power respectively.

6. The virtual power plant economic dispatch system based on distributed power generation according to claim 1 is characterized by: The power output of the gas turbine in the distributed generator set is obtained as follows: If the cost of electricity generated by a gas turbine is higher than the time-of-use electricity price in the distribution grid, the gas turbine will shut down; If the power generation cost of the gas turbine is lower than the time-of-use electricity price in the distribution network, the gas turbine will generate electricity, and the gas turbine power output at this time will be calculated according to the virtual power plant economic dispatch model; The power generation cost of the gas turbine is lower than the time-of-use electricity price in the distribution network. When there is uncontrollable distributed power generation and the energy storage system cannot fully absorb the excess power, the gas turbine obtains the corresponding gas turbine power output based on demand in combination with the virtual power plant economic dispatch model.

7. The virtual power plant economic dispatch system based on distributed power generation according to claim 1 is characterized by: The specific process of the virtual power plant compensating the output deviation of the virtual power plant by the combined operation of pumped storage hydropower generation and energy storage batteries is as follows: If the output deviation of the virtual power plant is greater than 0, indicating that the uncontrollable distributed generation is insufficient, the virtual power plant energy storage system will generate electricity. If the energy storage system is insufficient, the virtual power plant will purchase electricity from the distribution network to meet its output plan; If the output deviation is less than 0, indicating that the power generation of uncontrollable distributed generation exceeds the planned power generation, the energy storage system in the virtual power plant will store energy.

8. The virtual power plant economic dispatch system based on distributed power generation according to claim 1 is characterized by: The specific process of obtaining the optimal dispatching power generation plan for each time period of the future virtual power plant is as follows: The virtual power plant obtains the power output of each distributed generator set by solving the virtual power plant economic dispatch model, predicts the future power generation of uncontrollable distributed power generation, and obtains the output curve of distributed power generation of uncontrollable power sources in future interval time periods; The virtual power plant obtains the future power generation plan of the virtual power plant by comprehensively considering the distributed future power generation curve of the uncontrollable power source, the time-of-use electricity price in the distribution network, and the power generation cost of each distributed power generation unit; After considering the operation strategy of the virtual power plant based on time-of-use electricity price, the future real-time optimization scheduling plan is obtained according to the future virtual power plant power generation plan.

9. A method for economic dispatch modeling of a virtual power plant based on distributed generation, characterized in that: It follows the steps: By considering the management cost of distributed energy resources, the fuel cost of gas turbines, the penalty for deviation from the output plan, and the penalty for abandoning wind power generation and photovoltaic power generation, an objective function is constructed to maximize the economic benefits of the virtual power plant within a set time period. Compare the electricity purchase price in a set time period with the unit fuel cost of gas turbine power generation, and obtain the planned output of the virtual power plant based on distributed power generation under the corresponding circumstances; Constructing the operation constraints of the virtual power plant, constructing the economic dispatch model of the virtual power plant through the objective function and the operation constraints, and solving the economic dispatch model of the virtual power plant to obtain the power output of each distributed generator set; Combine pumped storage hydroelectric power generation and energy storage batteries to compensate for the output deviation of the virtual power plant, so that the actual output of the virtual power plant tracks the planned output of the virtual power plant; The power generation cost of each distributed generator set is calculated by multiplying the power output of each distributed generator set by the time-of-use electricity price in the distribution network. The distributed future power generation curve of the uncontrollable power source is obtained according to the power output of each distributed generator set. When the actual output of the virtual power plant tracks the planned output of the virtual power plant, the optimized scheduling power generation plan for each time period of the future virtual power plant is obtained according to the distributed future power generation curve of the uncontrollable power source, the time-of-use electricity price in the distribution network and the power generation cost of each distributed generator set.

10. A computer program product, comprising a computer program, characterized in that When the computer program is executed by a processor, the steps of the method described in claim 9 are implemented.

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