Pumped storage power station comprehensive value evaluation method and computer system

Abstract

The invention provides a comprehensive value evaluation method for a pumped storage power station and a computer system, which are suitable for value quantification and real-time optimization decision of the pumped storage power station in a novel power system containing high-proportion new energy and high-proportion power electronic equipment. The method comprises the following steps: loading a power system scheduling operation optimization model considering a new energy power generation power abandoning punishment mechanism and constraint conditions thereof, wherein the model aims at minimizing the total operation cost of the power system and the new energy power abandoning punishment; collecting power system basic data covering the structure, parameters and evaluation indexes of the power system, inputting the structure and parameters of the power system into the model and the constraint conditions of the model, and calculating operation data of the power system; and substituting the operation data and the evaluation indexes of the power system into the pumped storage power station value evaluation model, and quantitatively calculating the values of the pumped storage power station in economic, safe, social and environmental dimensions and the comprehensive value of the pumped storage power station in the power system.

Description

TECHNICAL FIELD

[0001] The application relates to a pumped storage power station comprehensive value evaluation method and a computer system. BACKGROUND

[0002] In recent years, the penetration rate of new energy power generation such as wind power and photovoltaic power is continuously improved, and the new power system presents the characteristics of high proportion of new energy and high proportion of power electronic equipment. However, new energy power generation has strong volatility and intermittency, and high proportion of access to the power system may lead to wind curtailment, light curtailment and load loss, thereby threatening the stable and reliable operation of the new energy power system. It is urgent to fully tap the flexibility resources on the source, network, load and storage sides to enhance the regulation capability of the power system.

[0003] As an effective flexible resource of the power system, the pumped storage power station has the ability of rapid start and stop and flexible output regulation, which helps to improve the consumption capacity of new energy, ensures the safe and stable operation of the system, and improves the economy and power supply quality of the power system. However, due to the lack of a unified pumped storage value evaluation system, the necessity and importance of its construction are often questioned. Under the planning of the total installed capacity target, it is difficult to avoid some pumped storage power stations with limited contribution to the construction of new power systems. Therefore, a comprehensive value evaluation technology of pumped storage power stations suitable for new power systems is urgently needed to scientifically guide the rational investment and orderly construction of pumped storage power stations.

[0004] At present, the value evaluation technology of pumped storage power stations mainly considers the operation characteristics of traditional power systems and focuses on the value measurement from the perspective of meeting the operation demand of the power grid. The existing method usually evaluates the value of pumped storage from a single dimension (such as economy), and cannot fully reflect the comprehensive role of pumped storage in improving the resilience of the power system, promoting new energy consumption and reducing carbon emissions. In addition, the existing evaluation technology does not fully consider the influence of the new energy curtailment penalty mechanism on the dispatching of the power system, resulting in deviation between the evaluation results and actual demand. Therefore, the application proposes a comprehensive value evaluation method of pumped storage power stations, which is multi-dimensional, dynamic and matched with the operation characteristics of new power systems. SUMMARY

[0005] The application proposes a comprehensive value evaluation method and computer system of pumped storage power stations, which is suitable for the value quantification and real-time optimization decision of pumped storage power stations in new power systems containing high proportion of new energy and high proportion of power electronic equipment.

[0006] A comprehensive value evaluation method of pumped storage power stations, comprising: loading a power system dispatching operation optimization model considering the new energy power generation curtailment penalty mechanism and its constraint conditions, the model aiming to minimize the total operation cost of the power system and the new energy curtailment penalty, and the expression of the model being: wherein:C t a total variable operation cost model of the thermal power generating unit, C r a new energy curtailment penalty model; collect power system basic data covering power system structure, parameters and evaluation indexes, input the power system structure and parameters into the model and its constraint conditions, calculate the operation data of the power system; substitute the operation data of the power system and the evaluation indexes into the pumped storage power station value evaluation model, and quantitatively calculate the value of the pumped storage power station in the economic, safe, social and environmental dimensions, and the comprehensive value in the power system.

[0007] The present application can comprehensively reflect the benefits of pumped storage in new power systems in multiple dimensions such as economy, system safety, society and environment; the present application quantitatively calculates the benefits by simulating the system operation with and without pumped storage participation, providing a scientific basis for investment returns and policy making; the present application helps guide the rational investment of pumped storage power stations and the improvement of power grid subsidy policies and price mechanisms, promoting the high-quality coordinated development of pumped storage and new energy systems. BRIEF DESCRIPTION OF DRAWINGS

[0008] Figure 1 is the installed capacity structure of a certain power grid.

[0009] Figure 2 is the typical daily load curve and wind-solar output curve of the region.

[0010] Figure 3 is a comprehensive value evaluation system diagram of pumped storage power stations. DETAILED DESCRIPTION

[0011] As an effective power system flexibility resource, pumped storage power stations can improve the stability and reliability of new energy power systems by adjusting power-energy balance. To scientifically guide the rational investment and orderly construction of pumped storage power stations, the present application proposes a multi-dimensional, dynamic and matched with the operation characteristics of new power systems comprehensive value evaluation method of pumped storage power stations. The method collects power grid and new energy data, establishes a dispatching model considering new energy curtailment penalty, constructs system operation simulation scenarios with and without pumped storage participation, and based on the operation simulation data, builds a value quantitative calculation model of pumped storage power stations in economy, safety, society and environment, realizing the comprehensive quantification of multi-dimensional value of pumped storage. The method can provide a scientific basis for investment decision, subsidy policy making and price mechanism design of pumped storage power stations in new power systems, thereby promoting the high-quality coordinated development of pumped storage industry and new power systems.

[0012] Step 1: Collect power system basic data covering power system structure, parameters and evaluation indexes.

[0013] Power System Structure: Power system installed capacity structure (capacity and distribution of generating units such as thermal power, hydropower, wind power, and photovoltaic power). Basic Parameters: Load curves, wind and solar power output curves, basic parameters of pumped storage power stations (such as installed capacity, head, efficiency, and charge / discharge characteristics). Evaluation Indicators: Evaluation parameters from economic, safety, social, and environmental dimensions (such as unit electricity cost, carbon emissions, and reliability indicators). Figure 1 The data shows the power generation capacity structure of a local power grid, with thermal power accounting for 68.70%, hydropower accounting for 12.29%, photovoltaic power accounting for 10.26%, and wind power accounting for 8.75%. Figure 2 This displays typical daily load and wind / solar power output curves for the region, where the long dashed line represents the load curve, the short dashed line represents the solar power output curve, and the dotted dashed line represents the wind power output curve. Figure 2 It is evident that the load curve is relatively low at night and high during the day, reflecting high electricity demand during the day; photovoltaic output is zero at night, but rises rapidly during the day; wind power output exhibits randomness and volatility. Table 1 provides basic information on pumped storage power stations in the region, and Table 2 further provides relevant power system parameters used for value assessment.

[0014] Table 1. Basic parameters of pumped storage power stations in a certain region's power system

[0015] Table 2. Parameters for Valuation of Pumped Storage Power Stations

[0016] Step 2: Load a new power system dispatch and operation optimization model that takes into account the penalty mechanism for curtailment of new energy power generation.

[0017] A novel power system dispatch and operation optimization model that takes into account the penalty mechanism for curtailment of renewable energy generation aims to minimize the variable cost of synchronous generator units in the entire power system and reduce the curtailment of renewable energy.

[0018] First, a total variable operating cost model for thermal power generating units in the new power system is established. This model should comprehensively consider the start-up and shutdown costs as well as the generation costs of the thermal power units. On an hourly time scale, the total start-up and shutdown cost model for thermal power units can be expressed as: (1) In the formula: C ts Total start-up and shutdown cost of thermal power generating units; T Number of time periods; N t This represents the number of thermal power units. For thermal power units n The start-stop cost (expressed as a constant for simplified calculation); For thermal power units n In t the operating state of the period, there are: (2) The total generation cost model of thermal power units in the hourly time scale can be expressed as: (3) In the formula: C tg is the total generation cost of thermal power units; is the unit power generation cost of thermal power units n ; is the generation power of thermal power units n in the period t .

[0019] Therefore, the total variable operating cost of thermal power units in the new power system can be obtained as: (4) In the formula: C t is the total variable operating cost of thermal power units.

[0020] Then, a new energy curtailment penalty model in the new power system is constructed, mainly including wind power and photovoltaic curtailment penalties.

[0021] The wind power curtailment penalty model is as follows: (5) In the formula: C rw is the wind power unit curtailment penalty; N w is the number of wind power units; η w is the wind power curtailment coefficient; is the wind power curtailment power.

[0022] The photovoltaic curtailment penalty model is as follows: (6) In the formula: C rp is the photovoltaic unit curtailment penalty; N p is the number of photovoltaic units; η p is the photovoltaic curtailment coefficient; is the photovoltaic curtailment power.

[0023] Therefore, the new energy curtailment penalty model in the new power system can be expressed as: (7) wherein: C r Penalty for new energy curtailment.

[0024] In summary, the new power system dispatching and operation model considering the penalty mechanism of new energy curtailment can be expressed as: (8) The objective function is to minimize the total operation cost of the power grid and the waste of new energy: (9) The constraint conditions include power balance constraints, spinning reserve constraints, and unit characteristics constraints, etc., as follows: (1) Considering the power balance constraints of wind power and photovoltaic power (10) wherein: is the wind turbine n in period t ; is the photovoltaic turbine n in period t ; K t is the number of pumped storage units in period t ; is the rated power of pumped storage units (assuming that pumping can only be operated at maximum power); N s is the number of pumped storage units; is the generation power of pumped storage units n in period t ; is the total load in period t ; is the total network loss in period t .

[0025] Wherein, the generation power of wind power and photovoltaic power can be further expressed as: (11) (12) wherein: is the upper limit of the generation of wind turbine n in period t ; is the upper limit of the generation of photovoltaic turbine n in period t .

[0026] (2) Spinning reserve constraints (13) (14) In the formula: and thermal power units n exist t Upper and lower limits of power generation during different time periods; Spinning reserve ratio; The spinning reserve rate added for wind power integration; The spinning reserve rate added for photovoltaic grid connection; This is the upper limit for solar power curtailment; This is the upper limit for wind power curtailment; and The positive and negative spinning reserves that a pumped-storage power station can provide, respectively, can be further expressed as: (15) (16) In the formula: for t The number of generator units in a pumped storage power station during a given period; and These are the upper and lower limits of power generation for pumped storage power station generator units, generally: (17) (18) (3) Climbing ability constraint (19) (20) In the formula: and They are thermal power generating units n The rate of increase or decrease in output speed; and These refer to the lifting and lowering output capacity of pumped storage power stations; and These are the proportions of the maximum fluctuations in wind power and solar power output to the total installed capacity, respectively. and These represent the total installed capacity of wind power and photovoltaic power, respectively.

[0027] (4) Constraints of pumped storage power stations 1) Storage capacity constraints (twenty one) In the formula: τ for T Any time period; Y 0 represents the initial water volume of the pumped storage power station; Y max and Ymin is the maximum water quantity and the minimum water quantity; k p and k g is the average water quantity / power quantity conversion coefficient during pumping and power generation.

[0028] 2) Power generation output constraint (22) In the formula: K is the total number of pumped storage power station units; K t is t the number of pumped storage power station pumping units in the period; is t the number of generator units of the pumped storage power station in the period; and are the upper limit and the lower limit of the rated power of the pumped storage unit, respectively.

[0029] 3) Daily power generation constraint (23) 4) Start-stop times constraint (24) In the formula: N L is the upper limit of the start-stop times of the pumped storage power station unit per day.

[0030] Step 3: Substitute the power system structure and parameters obtained in step 1 into the objective function and its constraints in step 2 to calculate the operation data of the power system.

[0031] Specifically, two scenarios with and without pumped storage power station participation in regulation are constructed, and a typical day is selected by using the Matlab platform CPLEX optimization solver to perform time period (such as hourly, daily) operation simulation on the above two scenarios, and obtain the data of thermal power unit start-stop state, power output, system operation cost, fuel consumption and new energy curtailment under each condition, as shown in Table 3.

[0032] Table 3 Typical operation data of power system

[0033] Step 4: Based on the power system operation data obtained in step 3, the value of the pumped storage power station is calculated from multiple dimensions such as economy, safety, society and environment, so as to build a comprehensive value evaluation model of the pumped storage power station.

[0034] First, a comprehensive value assessment index system for pumped storage power stations should be constructed, adapted to the characteristics of the power system. Pumped storage power stations possess unique technological advantages, enabling them to perform multiple functions such as peak shaving, frequency regulation, compensatory operation, energy storage, emergency backup, and black start. Based on the multi-dimensional contributions of pumped storage power stations to the new power system, the comprehensive value assessment system for pumped storage power stations should cover economic, safety, social, and environmental aspects, such as... Figure 3 As shown.

[0035] Then, based on the power system operation simulation output data obtained in step 3, a value assessment model for pumped storage power stations based on value substitution and multiple function superposition is constructed. For ease of comparison, when quantitatively analyzing the value of pumped storage, a typical day is selected to unify various functions at the daily scale, and then the annual assessment results are obtained based on the probability distribution of the typical day.

[0036] (1) Economic value assessment model 1) Savings in asset investment (25) In the formula: C th , C tr These are the unit investment costs for thermal power units and power transmission equipment, respectively. , These represent the total operating capacity of thermal power units with and without pumped storage; r th , r tr These are the depreciation rates for thermal power units and power transmission equipment, respectively. , These are the annual operation and maintenance rates for thermal power units and power transmission and distribution facilities, respectively. This is the maximum power generation capacity of the pumped storage power station. k r This is the capital recovery coefficient.

[0037] 2) Operating cost savings (26) In the formula: , Thermal power generating units with and without pumped storage power stations n During the period t The cost of electricity generation; , Thermal power generating units with and without pumped storage power stations n During the period t The start-up and shutdown costs.

[0038] (2) Safety value assessment model 1) Enhance the system flexibility adjustment capability (27) Wherein: , are the up / down regulation power of the pumped storage power station in the time period t ; k 1 and k 2 are the capacity and energy compensation standard coefficients of the power system, respectively; is the ratio of the actual regulation energy and the regulation capacity.

[0039] 2) Improve the system stability performance (28) Wherein: is the kinetic energy of the pumped storage unit n ; is the inertia compensation coefficient of the pumped storage unit n ; k 3, k 4, k 5 are the compensation standard coefficients of inertia, reserve capacity and black start, respectively; is the net power load of the pumped storage power station in the time period t ; is the maximum net power load of the pumped storage power station.

[0040] (3) Social value evaluation model (29) Wherein: f s is the average power outage frequency of the user; is the user loss evaluation rate; is the energy storage capacity of the pumped storage power station at time t .

[0041] (4) Environmental value evaluation model 1) Promote renewable energy consumption (30) Wherein: T on is the on-grid price; and are the power levels of the wind turbine n in the time period t with / without the pumped storage power station; and are the power levels of the photovoltaic unit n in the time period t with / without the pumped storage power station.

[0042] 2) emission reduction benefits (31) wherein: and are the standard coal consumption levels with / without pumped storage power station; and are the carbon emission coefficient and carbon emission trading price, respectively; c j and v j are the other pollutant emission coefficient and price, respectively.

[0043] In summary, the comprehensive value evaluation model of pumped storage power station can be expressed as: (32) Step 5: Based on the comprehensive value evaluation model of pumped storage power station constructed in step 4, the value of pumped storage power station in economic, safety, social, environmental and other dimensions, as well as the comprehensive value in the new power system are quantitatively calculated.

[0044] The application further provides a computer system. The system comprises a processor and a memory. The memory and the processor can be interconnected through a bus system and / or other forms of connection mechanism. The processor can include any one or more of a central processing unit (CPU), a graphics processing unit (GPU), a microprocessor (MP), or a digital signal processor (DSP). The memory can include a volatile memory, such as a random access memory (RAM). The memory can also include a non-volatile memory, such as a read-only memory (ROM), a flash memory, a hard disk drive (HDD) or a solid state drive (SSD). The memory stores executable program code, and the processor executes the executable program code to implement the comprehensive value evaluation of pumped storage power station. That is, the memory stores instructions for executing the comprehensive value evaluation method of pumped storage power station.

[0045] The application further provides a computer readable storage medium. For example, the computer readable storage medium is a non-transitory computer readable storage medium, such as a read-only memory (ROM), a random access memory (RAM), a compact disc read-only memory (CD-ROM), a magnetic tape, a floppy disk, an optical data storage device, or the like. The computer readable storage medium is used to store non-transitory computer readable instructions, and when the non-transitory computer readable instructions are executed by a computer, one or more steps in the comprehensive value evaluation method of the pumped storage power station can be implemented.

Claims

1. A method for assessing the overall value of a pumped storage power plant, characterized by, Comprise: The power system dispatching operation optimization model considering the new energy power generation abandoned electricity penalty mechanism and its constraint conditions, the model aims to minimize the total operation cost of the power system and the new energy abandoned electricity penalty, the expression of the model is: wherein: C t is a total variable operation cost model of the thermal power generating unit, C r is a new energy curtailment penalty model; Collect the basic data of the power system covering the structure, parameters and evaluation indexes of the power system, input the structure and parameters of the power system into the model and its constraint conditions, and calculate the operation data of the power system; Substitute the operation data and evaluation indexes of the power system into the pumped storage power station value evaluation model, and quantitatively calculate the value of the pumped storage power station in the economic, safety, social and environmental dimensions, as well as the comprehensive value in the power system.

2. The method of claim 1, wherein, The economic value calculation of the pumped storage power station value evaluation model includes the following formula: Asset investment savings: In the formula: C th , C tr are the unit investment costs of thermal power generating units and power transmission equipment, respectively; , are the total installed capacities of thermal power generating units with and without pumped storage, respectively; r th , r tr are the depreciation rates of thermal power generating units and power transmission equipment, respectively; , are the annual operation and maintenance rates of thermal power generating units and power transmission and distribution facilities, respectively; is the maximum power generation capacity of pumped storage power stations; k r is the capital recovery coefficient; Operation cost savings: In the formula: , are the costs of the thermal power generating units with / without pumped storage power stations n in the time period t ; , are the start-stop costs of the thermal power generating units with / without pumped storage power stations n in the time period t .

3. The method of claim 1, wherein, The safety value calculation of the pumped storage power station value evaluation model includes the following formula: Enhance the flexible adjustment capability of the power system: In the formula: , are the up / down regulation power of the pumped storage power station in the time period t ; k 1 and k 2 are the capacity and energy compensation standard coefficients of the power system, respectively; is the ratio of the actual regulation energy to the regulation capacity. Improve the stability performance of the power system: In the formula: is the kinetic energy of the pumped storage unit n ; is the kinetic energy of the pumped storage unit n ; k 3, k 4, k 5 are the compensation standard coefficients of inertia, standby capacity and black start, respectively; is the net power load of the pumped storage power station in the time period t ; is the maximum net power load of the pumped storage power station.

4. The method of claim 1, wherein, The social value calculation formula of the pumped storage power station value evaluation model is: wherein: f s is the average outage frequency for the user; is the user loss assessment rate; is the energy storage capacity of the pumped storage power station at time t .

5. The method of claim 1, wherein, The environmental value calculation of the pumped storage power station value evaluation model includes the following formula: Promote renewable energy consumption: wherein: T on is the on-grid electricity price; and are the power levels of the wind turbine n in the time period t with / without pumped storage power station, respectively; and are the power levels of the photovoltaic turbine n in the time period t with / without pumped storage power station, respectively. Emission reduction benefit: In the formula: and are the standard coal consumption levels with / without pumped storage; and are the carbon emission coefficient and carbon emission trading price, respectively; c j and v j are the other pollutant emission coefficient and price, respectively.

6. The method of claim 1, wherein, The comprehensive value is the sum of the economic, safety, social and environmental values.

7. The method of claim 1, wherein, The total variable operating cost model of the thermal power generating unit C t The expression is: In the formula, C ts is a total start-stop cost model of the thermal power generating unit, C ts is a total power generation cost model of the thermal power generating unit.

8. The method of claim 1, wherein, New energy curtailment penalty C r The expression is: wherein C rw penalty for wind turbine curtailment; C rp penalty for photovoltaic curtailment.

9. A computer system, characterized by Comprise: including processor and memory, the memory stores one or more computer program modules, the computer program modules are configured to be executed by the processor to realize the pumped storage power station comprehensive value evaluation method of any one of claims 1-8.

10. A non-transitory computer readable storage medium, comprising: The computer program is stored, and when the computer program is executed by the computer, the pumped storage power station comprehensive value evaluation method of any one of claims 1-8 can be realized.

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