A method for nuclear storage combined peak shaving considering step carbon trading combined with carbon capture

Abstract

This invention relates to a nuclear power-storage combined peak-shaving method considering tiered carbon trading combined with carbon capture. It includes: Step S1: Importing historical data such as wind, solar, and hydroelectric loads to extract typical scenarios; Step S2: Introducing dynamic time-of-use pricing to adjust system load demand; Step S3: Establishing a deep peak-shaving model for thermal power units to adjust and constrain their output; Step S4: Performing low-carbon retrofitting on thermal power units to establish a comprehensive and flexible carbon capture system; Step S5: Combining the characteristics of nuclear power units and pumped storage power stations to establish a nuclear power-storage combined peak-shaving model; Step S6: Solving the overall model using the Gurobi solver based on the typical scenarios in Step S1; Step S7: Outputting the dispatch output of each unit. This invention can improve the renewable energy absorption rate while balancing the system's low-carbon nature and economic efficiency.

Description

Technical Field

[0001] This invention relates to a nuclear power-shaving combined peak shaving method that considers tiered carbon trading combined with carbon capture. Background Technology

[0002] Since the beginning of the 21st century, with the rapid development of the national economy and the increasing demand for electricity, China's power industry has developed rapidly, with the total installed capacity of various power sources exceeding 2 billion kilowatts, among which the proportion of non-fossil energy power generation has increased significantly. However, due to the high proportion of new energy connected to the grid, the stable operation of the power grid has become more complex and uncertain, increasing the peak-shaving burden on thermal power units. Therefore, it is necessary to consider the peak-shaving capacity of nuclear power to meet peak-shaving demand while improving the absorption capacity of renewable energy.

[0003] Meanwhile, the environmental impact of over-reliance on fossil fuel power generation cannot be underestimated. Since my country clearly proposed the "dual carbon" target, low-carbon retrofitting of thermal power units has been an important measure and key method to achieve the "dual carbon" target. Introducing tiered carbon trading combined with carbon capture technology is one of the effective methods to reduce system carbon emissions.

[0004] Most studies addressing the insufficient peak-shaving capacity of the power system caused by the high proportion of renewable energy grid connection focus on deep peak shaving by thermal power or grid-based energy storage to meet peak-shaving demands, neglecting the ability and dispatchability of nuclear power units to participate in grid peak shaving. However, with the continuous increase in my country's installed nuclear power capacity, a large number of nuclear power units operating at base load will further increase the pressure on the power grid for peak shaving.

[0005] Currently, traditional thermal power units still rely on fossil fuels for power generation, resulting in severe carbon emissions, which runs counter to environmental protection goals. However, thermal power units still occupy a dominant position in my country's power industry installed capacity structure due to their sufficient reliability. This necessitates low-carbon retrofitting of thermal power units to alleviate the problem of excessive carbon emissions. Summary of the Invention

[0006] The purpose of this invention is to provide a nuclear power-pumped storage (NPS) combined peak shaving method that considers tiered carbon trading combined with carbon capture. Based on the low-carbon retrofitting of thermal power units, this invention focuses on reducing carbon emissions, improving the absorption rate of new energy sources, and mobilizing the enthusiasm of thermal power units for deep peak shaving. It establishes a deep peak shaving model for thermal power units that considers tiered carbon trading combined with carbon capture. Furthermore, based on the excellent complementary capabilities between nuclear power and pumped storage power stations, a three-stage load tracking mode is adopted for NPS combined peak shaving. Due to the good peak shaving capabilities of pumped storage power stations, NPS combined peak shaving operation can better meet the peak shaving needs of the power system and improve the power system's ability to absorb new energy sources.

[0007] To achieve the above objectives, the technical solution of the present invention is: a nuclear power-storage combined peak shaving method considering tiered carbon trading combined with carbon capture, comprising:

[0008] Step S1: Import historical data including scenery, water features, and lotus flowers, and extract typical scenes;

[0009] Step S2: Introduce dynamic time-of-use pricing to adjust system load demand;

[0010] Step S3: Establish a deep peak-shaving model for thermal power units to adjust and constrain the output of thermal power units;

[0011] Step S4: Carry out low-carbon retrofitting of thermal power units and establish a comprehensive and flexible carbon capture system;

[0012] Step S5: Combine the characteristics of nuclear power units and pumped storage power stations to establish a joint nuclear-storage peak-shaving model;

[0013] Step S6: Based on the typical scenario in Step S1, solve the nuclear-energy combined peak shaving model using the Gurobi solver;

[0014] Step S7: Output the power output of each unit.

[0015] In one embodiment of the present invention, step S4 is specifically implemented as follows:

[0016] (1) Tiered carbon trading model

[0017] The carbon trading mechanism is as follows: each unit has a portion of free carbon emission allowances. When its carbon emissions exceed the allocated allowances, it needs to purchase the excess carbon emission allowances from the carbon trading market. Conversely, it can sell the remaining allowances to the carbon trading market to generate revenue.

[0018] (1.1) Carbon emission model

[0019] E C =λP G (1)

[0020] In the formula: E C P represents the carbon emissions produced by the thermal power unit; λ represents the carbon emission intensity of the thermal power unit; G Indicates the output of the thermal power unit;

[0021] Therefore, the carbon trading volume of thermal power units participating in carbon trading is:

[0022] E C,a =E C -εP G (2)

[0023] In the formula: E C,aε represents the carbon trading volume of thermal power units participating in carbon trading; ε represents the carbon emission quota coefficient of thermal power units.

[0024] (1.2) Tiered carbon trading model

[0025] Tiered carbon trading divides carbon emission allowances into multiple trading zones at equal intervals. As the amount of carbon emission allowances to be purchased increases, the corresponding carbon trading price also increases, thereby promoting energy conservation and emission reduction. The tiered carbon trading model is as follows:

[0026]

[0027] In the formula: C CO2 α represents the carbon trading cost, γ represents the carbon trading base price, γ represents the carbon trading range length, and β represents the carbon trading price increase rate.

[0028] (2) Mathematical Model of Carbon Capture Power Plant

[0029] The total output of a carbon capture power plant after the low-carbon retrofit of thermal power units is divided into two parts: net output and capture energy consumption. Capture energy consumption is further divided into stationary energy consumption and operational energy consumption. The absorption energy consumption within the operational energy consumption is negligible. The mathematical model for the carbon capture power plant is as follows:

[0030]

[0031] Where: δ i E represents the flue gas split ratio of unit i; total E represents the total amount of CO2 captured by the unit. CG The amount of CO2 to be captured that can be supplied by the unit's solution storage is represented by μ; the carbon capture efficiency is represented by η; the maximum operating condition coefficient of the regeneration tower and compressor is represented by P. G,max To maximize the technical output of the unit; P B ζ represents the operating energy consumption of the carbon capture unit; P represents the energy consumption per unit of CO2 captured. J P is the net output of the thermal power unit. D This refers to the fixed energy consumption of the carbon capture unit.

[0032] In one embodiment of the present invention, step S5 is specifically implemented as follows:

[0033] To fully exploit the peak-shaving capacity of the combined operation of nuclear power and pumped storage, a three-stage combined operation peak-shaving model based on nuclear power peak shaving and supplemented by pumped storage is proposed. This model effectively tracks the load curve by tracking the peak-to-valley difference and the peak-to-valley difference of the load curve.

[0034] First, the daily average load curve is divided into three periods: peak, flat, and trough: P feng P ping Pgu Correspondingly, the output curve of the nuclear-electric combined unit is also divided into three segments: peak, flat and valley. The effective output of the nuclear-electric combined capacity is different in the three periods, and the operating status is also different.

[0035] The nuclear power plant will operate in a "12-1-10-1" mode, meaning 12 hours of low-power operation and 10 hours of high-power operation; the daily effective output time is 24 hours, and the installed capacity is G. He Its peak, flat, and trough power outputs are respectively: H feng H ping H gu The installed capacity of the pumped storage power station is G. CX Its peak, flat, and trough power outputs are respectively: S feng S ping S gu If the normal output is negative, it means that the pumped storage power station is in a pumping power consumption state during normal operation. In summary, the combined nuclear and pumped storage power output is: S feng +H feng H ping ±S ping H gu -S gu The maximum output of the three sections is less than or equal to the binding capacity S. max The independent operating capacity of a pumped storage power station is: S du The total output of the pumped storage power station at time t is P. CX,t The power contribution of those participating in the joint operation is: P kun,t The output power of independent operation is P du,t ;

[0036] Based on this, a mathematical model for peak shaving through combined nuclear and energy storage operations is obtained:

[0037] Normally in power generation mode:

[0038] Normally in pumping mode:

[0039] (I) Constructing the objective function

[0040] The objective function is to minimize the total system cost C. An optimal scheduling model is established with this objective in mind, incorporating the system operating cost C. YX Penalty Cost C CF Its expression is:

[0041] C = C YX +C CF (7)

[0042] (1) System operating cost C YX

[0043] System operating costs include the operating costs of thermal power units (C). G Nuclear power unit operating cost C HE Operating cost of pumped storage power station C CX And carbon trading costs C CO2 Its expression is:

[0044] C YX =C G +C HE +C CX +C CO2 +C R (8)

[0045] (1.1) Operating cost of thermal power units C G

[0046] The cost of generating electricity from thermal power units is much higher than that from renewable energy sources, primarily wind and solar power. Therefore, the cost of renewable energy generation, including coal consumption cost C, is ignored. G1 Start-up and shutdown costs C G2 Hot standby cost C G3 Loss cost C G4 , fuel cost of oil injection G5 ;

[0047]

[0048]

[0049]

[0050]

[0051] S R,t =P Gmax -P G,t (13)

[0052] C G4 =dρS G (14)

[0053] C G5 =Oil cost S oil (15)

[0054] In the formula, a g b g c g These are the fuel cost coefficients for thermal power units; P G,t S represents the output of the thermal power unit at time t; g U represents the start-up and shutdown cost coefficient for thermal power plants. G The thermal power plant is in operation; C s,tS represents the unit's hot standby cost coefficient. R,t d represents the thermal standby capacity of the unit; d represents the service life loss rate of the thermal power unit; ρ represents the influence coefficient of the thermal power unit; S G Unit purchase cost of thermal power units; Oil cost The amount of fuel consumed per unit time for deep peak shaving and fuel stabilization of the unit; S oil For oil prices;

[0055] The cost modeling method based on hot standby capacity yields the unit hot standby cost coefficient C. s,t and electricity price ρ t The relationship between them is shown in equation (16):

[0056]

[0057] (1.2) Total operating cost of nuclear power unit C HE

[0058] The total operating cost of a nuclear power unit consists of the nuclear power operating cost, the additional fuel cost and safety cost caused by nuclear power peak shaving:

[0059]

[0060] P N =P N,f +σP N,s (18)

[0061] In the formula, a HE b HE These are the conventional operating cost coefficients for nuclear power units; P HE,t P represents the output of the nuclear power unit at time t. HE,t P HE,t,N These are the nuclear power plant's dispatch output and rated output, respectively; P N P represents the peak-shaving cost coefficient for nuclear power. N,f P is the peak-shaving fuel cost coefficient. N,s σ is the peak-shaving safety cost coefficient; σ is the nuclear power safety value coefficient, used to balance the safety and economy of nuclear power peak shaving.

[0062] (1.3) Operating cost C of pumped storage unit CX

[0063] The operating cost of a pumped storage unit is its start-up and shutdown cost:

[0064]

[0065] In the formula, S FD U represents the startup cost coefficient for pumped storage power generation. FD This is the pumped storage power generation operation status; S CSU represents the pumped storage pumping start-up cost coefficient. CS The pumped storage system is in operation.

[0066] (2) Penalty cost C CF

[0067]

[0068] In the formula, P ww,t P pvv,t P wwater,t These represent the maximum output of the wind turbine, the maximum output of the photovoltaic power plant, and the maximum output of the hydropower unit at time t, respectively; P W,t P PV,t P water,t These represent the power outputs of the wind turbine, photovoltaic power unit, and hydropower unit at time t, respectively; q w q v q water These are the unit cost of wind curtailment penalty, the unit cost of solar curtailment penalty, and the unit cost of hydropower curtailment;

[0069] (3) Carbon capture cost C R

[0070] The cost of carbon capture integration is the discounted cost of the carbon capture equipment, C. Z The solvent loss cost C during the carbon capture process S composition:

[0071] C R =C Z +C S (twenty one)

[0072]

[0073]

[0074] In the formula, C FL and N ZJ These represent the total cost and depreciation period of the carbon capture equipment, respectively; r is the discount rate for the carbon capture power plant project; P RY V represents the total cost per unit volume of solution storage; RV and N RY These represent the volume and depreciation period of the solution storage device, respectively; K S This represents the cost coefficient of ethanolamine solvent. E represents the solvent operating loss coefficient. total,n,t This represents the amount of carbon captured by the i-th carbon capture unit at time t;

[0075] (II) Constraints

[0076] (1) Thermal power unit constraints

[0077] This includes upper and lower limits of thermal power unit output, thermal power unit ramping constraints, thermal power unit spinning reserve constraints, and thermal power unit loss constraints.

[0078] P G,min ≤P G,t ≤P G,max (twenty four)

[0079] P G,t -P G,t-1 ≤k g *P G,max (25)

[0080] P G,max -P G,t ≥0.01*P load1 (26)

[0081] P G,t -P G,min ≥0.01*P load1 (27)

[0082] In the formula, P G,min The minimum technical output of a thermal power unit during normal peak shaving is 0.5 * P. G,max The peak value during deep peak tuning is 0.3*P. G,max ;P G,t-1 P G,t These represent the output of the thermal power unit at times t-1 and t, respectively; k g P is the ramp rate of the thermal power unit. load1 The load after implementing a demand response mechanism;

[0083] (2) Constraints of hydropower units

[0084] 0≤P water,t ≤P wwater,t (28)

[0085] P water,t -P water,t-1 ≤k water *G water (29)

[0086] In the formula, P water,t-1 P water,t These represent the output of the hydropower unit at times t-1 and t, respectively; k water G is the hydroelectric generator's ramp-up rate. water The capacity of the hydroelectric generator assembly;

[0087] (3) Constraints on new energy output

[0088] 0≤P W,t ≤P ww,t (30)

[0089] 0≤P PV,t ≤P pvv,t (31)

[0090] (4) Operating output constraints of nuclear power units

[0091]

[0092] (5) Operational constraints of pumped storage units

[0093]

[0094]

[0095]

[0096] In the formula, U cs The pumped storage unit is in pumping mode; U fd This refers to the pumped-storage unit's power generation status. During peak load periods, the pumped-storage unit should generate power to reduce peak loads; during off-peak load periods, the pumped-storage unit should pump water to fill the valleys. G cx,min This represents the lower limit of pumped storage power generation capacity; G cx,max This represents the upper limit of pumped storage power generation (pumping) capacity; P FD P represents the power generation of the pumped-storage unit. CS η is the pumping capacity of the pumped storage unit; cx To improve the operating efficiency of pumped storage units. At the same time, the pumping and power generation conditions of pumped storage cannot change abruptly;

[0097] (6) Load shedding constraint

[0098]

[0099] In the formula, P load0 This represents the actual load; P load1 The load after implementing a demand response mechanism; ξ load The percentage of load shedding allowed by the system;

[0100] (7) Constraints related to carbon capture

[0101]

[0102] In the formula: V F,i,t V represents the volume of solution in the flooded storage tank of unit i at time t; CA,i,t V represents the volume of solution required by the solution storage of unit i to release CO2 at time t; P,i,t V represents the volume of the lean solution reservoir in unit i at time t; CR V represents the capacity of the solution storage device. CA,i,t The expression is:

[0103]

[0104] Where: M MEA M represents the molar mass of monoethanolamine (MEA); CO2 θ represents the molar mass of carbon dioxide (CO2); θ represents the output of the regeneration tower; ψ R Indicates the concentration of the alkanolamine solution; ρ R This indicates the density of an alkanolamine solution;

[0105] Since the carbon capture unit was converted from a thermal power unit, the net processing range of the power system after the conversion is constrained as follows:

[0106] P G,min -ζημλδP G,max -P D ≤P J ≤P G,max -P D (39)

[0107] (8) Power balance constraint

[0108] P W,t +P PV,t +P water,t +P J,t +P HE,t +P CX,t =P load1 (40)

[0109] Compared to existing technologies, this invention has the following advantages: The method of this invention can improve the grid's absorption rate of renewable energy under high-proportion renewable energy grid-connected operation, and fully utilize the dispatchability of nuclear power. Simultaneously, it introduces tiered carbon trading and transforms thermal power units into carbon capture units, achieving the low-carbon goals of the power system. Attached Figure Description

[0110] Figure 1 The present invention considers a multi-power nuclear power and energy storage joint peak shaving optimization scheduling flowchart that combines tiered carbon trading with carbon capture. Detailed Implementation

[0111] The technical solution of the present invention will now be described in detail with reference to the accompanying drawings.

[0112] This invention provides a nuclear power-storage combined peak-shaving method considering tiered carbon trading combined with carbon capture, comprising:

[0113] Step S1: Import historical data including scenery, water features, and lotus flowers, and extract typical scenes;

[0114] Step S2: Introduce dynamic time-of-use pricing to adjust system load demand;

[0115] Step S3: Establish a deep peak-shaving model for thermal power units to adjust and constrain the output of thermal power units;

[0116] Step S4: Carry out low-carbon retrofitting of thermal power units and establish a comprehensive and flexible carbon capture system;

[0117] Step S5: Combine the characteristics of nuclear power units and pumped storage power stations to establish a joint nuclear-storage peak-shaving model;

[0118] Step S6: Based on the typical scenario in Step S1, solve the nuclear-energy combined peak shaving model using the Gurobi solver;

[0119] Step S7: Output the power output of each unit.

[0120] The following is a detailed implementation process of the present invention.

[0121] This invention provides a nuclear-storage combined peak shaving method that considers tiered carbon trading combined with carbon capture, and establishes an optimization model for nuclear-storage combined peak shaving scheduling with multiple types of power sources that considers carbon capture.

[0122] (1) Based on the idea of ​​low-carbon transformation of thermal power units, we will start from reducing carbon emissions, improving the absorption rate of new energy, and mobilizing the enthusiasm of thermal power units for deep peak shaving, and establish a deep peak shaving model for thermal power units that considers the combination of tiered carbon trading and carbon capture.

[0123] (2) Based on the excellent complementary capabilities between nuclear power and pumped storage power stations, a three-stage tracking load mode is adopted for joint nuclear-pumped storage peak shaving. Based on the good peak shaving capabilities of pumped storage power stations, joint nuclear-pumped storage peak shaving operation can better meet the peak shaving needs of the power system and enhance the power system's ability to absorb new energy sources.

[0124] This invention can improve the grid's absorption rate of renewable energy under high-proportion renewable energy grid-connected operation and fully utilize the dispatchability of nuclear power. It also introduces tiered carbon trading and transforms thermal power units into carbon capture units, achieving the low-carbon goals of the power system. The technical effects of this invention are shown in Table 1, with specific embodiments. Scheme 1 is the traditional scheme where thermal power units only perform conventional peak shaving, while the nuclear power plant operates at base load. Scheme 2 is an improved scheme where thermal power units undergo deep peak shaving, while the nuclear power plant still operates at base load. Scheme 3 involves deep peak shaving and low-carbon transformation of thermal power units, while the nuclear power plant and pumped storage power station jointly perform peak shaving, which is the optimized scheme proposed in this invention.

[0125] Table 1 Comparison of the effects of different methods

[0126]

[0127]

[0128] As shown in Table 1, when thermal power units only perform conventional peak shaving while nuclear power plants operate at base load, the limited output capacity of thermal power units results in insufficient adjustable capacity, leading to a series of renewable energy curtailment issues. Therefore, it is necessary to carry out deep peak shaving retrofits on thermal power units to alleviate the renewable energy consumption problem. When Scheme 2, based on Scheme 1, performs deep peak shaving retrofits on thermal power units, it can be seen that the renewable energy curtailment rate decreased by 1%. The coal-saving characteristics of wind power significantly reduced the total operating cost of the system, providing some relief to the curtailment problem, but it is still slightly insufficient. At the same time, since deep peak shaving increases the carbon emission intensity of the units, the decrease in carbon emissions is only due to the reduction in the output of thermal power units and does not represent a low-carbon characteristic of this scheme. However, by implementing the optimized scheme proposed in this invention, the renewable energy curtailment rate can be reduced to 0.35%, almost achieving full renewable energy consumption. While ensuring the efficient utilization of renewable energy, the carbon emission coefficient is reduced to 0.5482, truly realizing the low-carbonization of the power system.

[0129] This invention considers a multi-power nuclear power and energy storage joint peak-shaving optimization scheduling process that combines tiered carbon trading with carbon capture, such as... Figure 1 As shown.

[0130] 1. Peak, flat, and valley time periods

[0131] Based on the fluctuation pattern of the daily load curve in the power system, it can be divided into off-peak periods, mid-load periods, and peak periods. Therefore, the new method promotes peak-valley time-of-use pricing in the electricity sales strategy. The peak-valley time-of-use pricing and time period division in the electricity market are shown in Table 2.

[0132] Table 2 Peak-Valley Time-of-Use Electricity Prices and Time Segments

[0133]

[0134] 2. Deep Peak Shaving Model for Low-Carbonization of Thermal Power

[0135] Given China's current power structure, both installed capacity and power generation are dominated by thermal power. Deep peak shaving by thermal power units remains the primary means of promoting the absorption of new energy sources and ensuring stable load operation in the power system, effectively addressing the uncertainties brought to the power supply or load side by a high proportion of new energy grid connection. However, this reliance on thermal power units also results in persistently high carbon emissions from the power system, highlighting the increasing importance of low-carbon retrofitting of thermal power units.

[0136] (1) Tiered carbon trading model

[0137] The carbon trading models currently in use are largely similar and can alleviate carbon emission problems in various industries to some extent. The carbon trading mechanism generally works as follows: each generating unit receives a portion of free carbon emission allowances. When its carbon emissions exceed the allocated allowances, it needs to purchase the excess allowances from the carbon trading market. Conversely, it can sell the remaining allowances to the carbon trading market to generate revenue.

[0138] (1.1) Carbon emission model

[0139] E C =λP G (1)

[0140] In the formula: E C P represents the carbon emissions produced by the thermal power unit; λ represents the carbon emission intensity of the thermal power unit; G This indicates the output of the thermal power unit.

[0141] Therefore, the carbon trading volume of thermal power units participating in carbon trading is:

[0142] E C,a =E C -εP G (2)

[0143] In the formula: E C,a ε represents the carbon trading volume of thermal power units participating in carbon trading; ε represents the carbon emission quota coefficient of thermal power units.

[0144] (1.2) Tiered carbon trading model

[0145] The biggest difference between tiered carbon trading and traditional carbon trading is that it divides carbon emission allowances into multiple equally spaced trading zones. As the amount of carbon emission allowances to be purchased increases, the corresponding price per carbon trading unit also increases, thereby promoting energy conservation and emission reduction. The tiered carbon trading model is as follows:

[0146]

[0147] In the formula: C CO2 α represents the carbon trading cost, γ represents the carbon trading base price, γ represents the carbon trading range length, and β represents the carbon trading price increase rate.

[0148] (2) Mathematical Model of Carbon Capture Power Plant

[0149] The total output of a carbon capture power plant after the low-carbon retrofit of thermal power units is generally divided into two parts: net output and capture energy consumption. Capture energy consumption can be further divided into stationary energy consumption and operational energy consumption, with the absorption energy consumption within operational energy consumption being negligible. The mathematical model for a carbon capture power plant is as follows:

[0150]

[0151] Where: δ i E represents the flue gas split ratio of unit i; total E represents the total amount of CO2 captured by the unit. CG The amount of CO2 to be captured that can be supplied by the unit's solution storage is represented by μ; the carbon capture efficiency is represented by η; the maximum operating condition coefficient of the regeneration tower and compressor is represented by P. G,max To maximize the technical output of the unit; P B ζ represents the operating energy consumption of the carbon capture unit; P represents the energy consumption per unit of CO2 captured. J P is the net output of the thermal power unit. D This refers to the fixed energy consumption of the carbon capture unit.

[0152] 3. Nuclear-Storage Combined Operation Peak Shaving Model

[0153] To fully exploit the peak-shaving capacity of the combined operation of nuclear power and pumped storage, this paper proposes a three-stage combined operation peak-shaving model based on nuclear power peak shaving and supplemented by pumped storage. This model effectively tracks the load curve by tracking the peak-to-valley difference and the load curve level difference.

[0154] The model first divides the daily average load curve into three periods: peak, flat, and trough: P feng P ping P gu Correspondingly, the output curve of the nuclear-electric combined unit is also divided into three segments: peak, flat, and valley. The effective output of the combined nuclear-electric capacity varies in each of the three periods, and the operating status also differs.

[0155] The nuclear power plant will operate in a "12-1-10-1" mode, meaning 12 hours of low-power operation followed by 10 hours of high-power operation. The daily effective output time is 24 hours, and the installed capacity is G. He Its peak, flat, and trough power outputs are respectively: H feng H ping H gu The installed capacity of the pumped storage power station is G. CX Its peak, flat, and trough power outputs are respectively: S feng S ping S gu If the normal output is negative, it means that the pumped-storage power station is in a pumping power consumption state during normal operation. In summary, the combined nuclear and pumped-storage power output is: S feng +H feng H ping ±S ping H gu -S gu The maximum output of the three sections is less than or equal to the binding capacity S. maxThe independent operating capacity of a pumped storage power station is: S du The total output of the pumped storage power station at time t is P. CX,t The power contribution of those participating in the joint operation is: P kun,t The output power of independent operation is P du,t ;

[0156] Based on this, a mathematical model for peak shaving through combined nuclear and energy storage operations is obtained:

[0157] Normally in power generation mode:

[0158] Normally in pumping mode:

[0159] 4. Objective function

[0160] The objective function is to minimize the total system cost C. An optimal scheduling model is established based on this objective. This model primarily includes the system operating cost C. YX Penalty Cost C CF Carbon capture integration cost C R Its expression is:

[0161] C = C YX +C CF (7)

[0162] (1) System operating cost C YX

[0163] System operating costs include the operating costs of thermal power units (C). G Nuclear power unit operating cost C HE Operating cost of pumped storage power station C CX And carbon trading costs C CO2 Its expression is:

[0164] C YX =C G +C HE +C CX +C CO2 +C R (8)

[0165] (1.1) Operating cost of thermal power units C G

[0166] The power generation cost of thermal power units is much higher than that of renewable energy sources, mainly wind and solar power. Therefore, this paper ignores the power generation cost of renewable energy sources, including the coal consumption cost C. G1 Start-up and shutdown costs C G2 Hot standby cost C G3 Loss cost C G4 Oil-fired fuel cost C G5 .

[0167]

[0168]

[0169]

[0170]

[0171] S R,t =P Gmax -P G,t (13)

[0172] C G4 =dρS G (14)

[0173] C G5 =Oil cost S oil (15)

[0174] In the formula, a g b g c g These are the fuel cost coefficients for thermal power units; P G,t S represents the output of the thermal power unit at time t; g U represents the start-up and shutdown cost coefficient for thermal power plants. G The thermal power plant is in operation; C s,t S represents the unit's hot standby cost coefficient. R,t d represents the thermal standby capacity of the unit; d represents the service life loss rate of the thermal power unit; ρ represents the influence coefficient of the thermal power unit; S G Unit purchase cost of thermal power units; Oil cost The amount of fuel consumed per unit time for deep peak shaving and fuel stabilization of the unit; S oil For oil prices.

[0175] The cost modeling method based on hot standby capacity yields the unit hot standby cost coefficient C. s,t and electricity price ρ t The relationship between them is shown in equation (16).

[0176]

[0177] (1.2) Total operating cost of nuclear power unit C HE

[0178] The total operating cost of a nuclear power unit mainly consists of the nuclear power operating cost, the additional fuel cost caused by nuclear power peak shaving, and the safety cost.

[0179]

[0180] P N =P N ,f+σP N ,s(18)

[0181] In the formula, a HE b HE These are the conventional operating cost coefficients for nuclear power units; P HE,t P represents the output of the nuclear power unit at time t. HE ,t、P HE ,t,N represent the dispatched output and rated output of the nuclear power plant, respectively; P N P represents the peak-shaving cost coefficient for nuclear power. N,f P is the peak-shaving fuel cost coefficient. N,s σ is the peak-shaving safety cost coefficient; σ is the nuclear power safety value coefficient, used to balance the safety and economy of nuclear power peak shaving.

[0182] (1.3) Operating cost C of pumped storage unit CX

[0183] Generally, the operating cost of a pumped storage unit is its start-up and shutdown cost:

[0184]

[0185] In the formula, S FD U represents the startup cost coefficient for pumped storage power generation. FD This is the pumped storage power generation operation status; S CS U represents the pumped storage pumping start-up cost coefficient. CS This indicates the pumped storage and pumping operation status.

[0186] (1.4) Carbon trading cost C CO2

[0187] See equation (3).

[0188] (2) Penalty cost C CF

[0189]

[0190] In the formula, P ww,t P pvv,t P wwater,t These represent the maximum output of the wind turbine, the maximum output of the photovoltaic power plant, and the maximum output of the hydropower unit at time t, respectively; P W,t P PV,t P water,t These represent the power outputs of the wind turbine, photovoltaic power unit, and hydropower unit at time t, respectively; q w q v q water These are the unit cost of wind curtailment penalty, the unit cost of solar curtailment penalty, and the unit cost of water curtailment penalty.

[0191] (3) Carbon capture cost C R

[0192] The cost of carbon capture integration is the discounted cost of the carbon capture equipment, C. Z The solvent loss cost C during the carbon capture process S composition:

[0193] C R =C Z +C S (twenty one)

[0194]

[0195]

[0196] In the formula, C FL and N ZJ These represent the total cost and depreciation period of the carbon capture equipment, respectively; r is the discount rate for the carbon capture power plant project; P RY V represents the total cost per unit volume of solution storage; RV and N RY These represent the volume and depreciation period of the solution storage device, respectively; K S E represents the solvent cost factor for ethanolamine, θ represents the solvent operating loss factor, and E total,n,t Let represent the amount of carbon captured by the i-th carbon capture unit at time t.

[0197] 5. Constraints

[0198] (1) Thermal power unit constraints

[0199] This includes upper and lower limits of thermal power unit output, thermal power unit ramping constraints, thermal power unit spinning reserve constraints, and thermal power unit loss constraints.

[0200] P G,min ≤P G,t ≤P G,max (twenty four)

[0201] P G,t -P G,t-1 ≤k g *P G,max (25)

[0202] P G,max -P G,t ≥0.01*P load1 (26)

[0203] P G,t -P G,min ≥0.01*P load1 (27)

[0204] In the formula, P G,min The minimum technical output of a thermal power unit during normal peak shaving is 0.5 * P. G,max The peak value during deep peak tuning is 0.3*P. G,max ;P G,t-1 P G,t These represent the output of the thermal power unit at times t-1 and t, respectively; k g P is the ramp rate of the thermal power unit. load1 The load after adopting a demand response mechanism.

[0205] (2) Constraints of hydropower units

[0206] 0≤P water,t ≤P wwater,t (28)

[0207] P water,t -P water,t-1 ≤k water *G water (29)

[0208] In the formula, P water,t-1 P water,t These represent the output of the hydropower unit at times t-1 and t, respectively; k water G is the hydroelectric generator's ramp-up rate. water This refers to the installed capacity of the hydroelectric generator.

[0209] (3) Constraints on new energy output

[0210] 0≤P W,t ≤P ww,t (30)

[0211] 0≤P PV,t ≤P pvv,t (31)

[0212] (4) Operating output constraints of nuclear power units

[0213]

[0214] (5) Operational constraints of pumped storage units

[0215]

[0216]

[0217]

[0218] In the formula, U cs The pumped storage unit is in pumping mode; U fdThis refers to the pumped-storage unit's power generation status. During peak load periods, the pumped-storage unit should generate power to reduce peak loads; during off-peak load periods, the pumped-storage unit should pump water to fill the valleys. G cx,min This represents the lower limit of pumped storage power generation capacity; G cx,max This represents the upper limit of pumped storage power generation (pumping) capacity; P FD P represents the power generation of the pumped-storage unit. CS η is the pumping capacity of the pumped storage unit; cx This is to improve the operating efficiency of pumped storage units. At the same time, the pumping and power generation conditions of pumped storage cannot change abruptly.

[0219] (6) Load shedding constraint

[0220]

[0221] In the formula, P load0 This represents the actual load; P load1 The load after implementing a demand response mechanism; ξ load This represents the percentage of load that the system is allowed to discard.

[0222] (7) Constraints related to carbon capture

[0223]

[0224] In the formula: V F,i,t V represents the volume of solution in the flooded storage tank of unit i at time t; CA,i,t V represents the volume of solution required by the solution storage of unit i to release CO2 at time t; P,i,t V represents the volume of the lean solution reservoir in unit i at time t; CR This represents the capacity of the solution storage device. Where V CA,i,t The expression is:

[0225]

[0226] Where: M MEA M represents the molar mass of monoethanolamine (MEA); CO2 θ represents the molar mass of carbon dioxide (CO2); θ represents the output of the regeneration tower; ψ R Indicates the concentration of the alkanolamine solution; ρ R This indicates the density of the alkanolamine solution.

[0227] Since carbon capture units are generally converted from thermal power units, the net processing range of the power system after the conversion of thermal power units is constrained as follows:

[0228] P G,min -ζημλδP G,max -P D ≤P J ≤P G,max -PD (39)

[0229] (8) Power balance constraint

[0230] P W,t +P PV,t +P water,t +P J,t +P HE,t +P CX,t =P load1 (40)

[0231] The above are preferred embodiments of the present invention. Any changes made to the technical solution of the present invention that do not exceed the scope of the technical solution of the present invention shall fall within the protection scope of the present invention.

Claims

1. A method of nuclear accumulation combined with peak shaving considering stepwise carbon trading combined with carbon capture, characterized by, include: Step S1: Import historical data including scenery, water features, and lotus flowers, and extract typical scenes; Step S2: Introduce dynamic time-of-use pricing to adjust system load demand; Step S3: Establish a deep peak-shaving model for thermal power units to adjust and constrain the output of thermal power units; Step S4: Carry out low-carbon retrofitting of thermal power units and establish a comprehensive and flexible carbon capture system; Step S5: Combine the characteristics of nuclear power units and pumped storage power stations to establish a joint nuclear-storage peak-shaving model; Step S6: Based on the typical scenario in Step S1, solve the nuclear power and energy storage joint peak shaving model using the Gurobi solver; Step S7: Output the power output of each unit; Step S5 is implemented as follows: To fully exploit the peak-shaving capacity of the combined operation of nuclear power and pumped storage, a three-stage combined operation peak-shaving model based on nuclear power peak shaving and supplemented by pumped storage is proposed. This model effectively tracks the load curve by tracking the peak-to-valley difference and the peak-to-valley difference of the load curve. First, the daily average load curve is divided into three periods: peak, flat, and trough. , , Correspondingly, the output curve of the nuclear-electric combined unit is also divided into three segments: peak, flat and valley. The effective output of the nuclear-electric combined capacity is different in the three periods, and the operating status is also different. The nuclear power plant will operate in a "12-1-10-1" mode, meaning 12 hours of low-power operation and 10 hours of high-power operation; the effective daily output time is 24 hours, and the installed capacity is... Its peak, flat, and trough power outputs are respectively: , , The installed capacity of the pumped storage power station is Its peak, flat, and trough power outputs are respectively: , , If the normal output is negative, it means that the pumped storage power station is in a pumping power consumption state during normal operation. In summary, the combined output of nuclear and pumped storage systems is as follows: , , The maximum output of the three stages is less than or equal to the binding capacity. The independent operating capacity of a pumped storage power station is: The total output of the pumped storage power station at time t is The contributions from those participating in the joint operation are as follows: Independent operation output is ; Based on this, a mathematical model for peak shaving through combined nuclear and energy storage operations is obtained: (5) (6) (a) Constructing the objective function The objective function is the total system cost. To minimize system operating costs, an optimal scheduling model is established. Penalty costs Its expression is: (7) (1) System operating costs The system operation cost includes the operation cost of the thermal power unit , the operation cost of the nuclear power unit , the operation cost of the pumped storage power station and the carbon trading cost ; and the expression is: (8) (1.1) Operation cost of thermal power unit The cost of generating electricity from thermal power units is much higher than that from renewable energy sources, primarily wind and solar power. Therefore, the cost of renewable energy generation, including coal consumption costs, is ignored. Start-up and shutdown costs Hot standby cost Loss and cost Stable fuel costs due to oil injection ; (9) (10) (11) (12) (13) (14) (15) In the formula, , , These are the fuel cost coefficients for thermal power units; Let t be the output of the thermal power unit; This refers to the start-up and shutdown cost coefficient for thermal power plants. The thermal power plant is in operation. This is the unit's hot standby cost coefficient; This is the unit's hot standby capacity; The service life loss rate of thermal power units; This represents the influence coefficient of thermal power units; Unit purchase cost of thermal power units; The amount of fuel consumed per unit time for deep peak shaving and fuel stabilization of the unit; For oil prices; Cost modeling methods based on hot standby capacity yield unit hot standby cost coefficients. and electricity prices The relationship between them is shown in equation (16): (16) (1.2) Total operating cost of nuclear power units The total operating cost of a nuclear power unit consists of the nuclear power operating cost, the additional fuel costs and safety costs caused by nuclear power peak shaving: (17) (18) In the formula, , These are the conventional operating cost coefficients for nuclear power units; The output of the nuclear power unit at time t; , These are the nuclear power plant's dispatch output and rated output, respectively. This is the peak-shaving cost coefficient for nuclear power. This is the peak-shaving fuel cost coefficient; This is the peak-shaving safety cost coefficient; This is the nuclear power safety value coefficient, used to balance the safety and economy of nuclear power peak shaving. (1.3) Pumped storage unit operating cost The operating cost of a pumped storage unit is its start-up and shutdown cost: (19) In the formula, This is the startup cost coefficient for pumped storage power generation; This is the pumped storage power generation operation status; The pumped storage pumping start-up cost coefficient; The pumped storage system is in operation. (2) penalty cost (20) In the formula, , , These represent the maximum output of the wind turbine, the maximum output of the photovoltaic system, and the maximum output of the hydropower unit at time t, respectively. , , These represent the power output of the wind turbine, the photovoltaic power unit, and the hydropower unit at time t, respectively. , , These are the unit cost of wind curtailment penalty, the unit cost of solar curtailment penalty, and the unit cost of hydropower curtailment; (3) Carbon capture costs Carbon capture cost from carbon capture plant discounted cost With solvent loss cost in carbon capture process Composition: (21) (22) (23) In the formula, and These are the total cost and depreciation period of the carbon capture equipment, respectively. Discount rate for carbon capture power plant projects; The total cost per unit volume of solution storage; and These are the volume and depreciation period of the solution storage device, respectively. This represents the cost coefficient of ethanolamine solvent. Indicates the solvent operating loss coefficient. Indicates the first Taiwan carbon capture unit Carbon capture at any given time; (ii) Constraints (1) Constraints of thermal power units This includes upper and lower limits of thermal power unit output, thermal power unit ramping constraints, thermal power unit spinning reserve constraints, and thermal power unit loss constraints. (24) (25) (26) (27) In the formula, For the minimum technical output of thermal power units, during normal peak shaving: Deep peak shaving is ; , For thermal power units , Efforts made at all times; The ramp rate of the thermal power unit; The load after implementing a demand response mechanism; (2) Constraints of hydropower units (28) (29) In the formula, , The hydropower units are respectively , Efforts made at all times; The rate of ascent for the hydroelectric generator unit; The capacity of the hydroelectric generator assembly; (3) Constraints on new energy output (30) (31) (4) Operating output constraints of nuclear power units (32) (5) Operating constraints of pumped storage units (33) (34) (35) In the formula, The pumped storage unit is in pumping mode; This refers to the pumped storage unit's power generation status; when the load is at its peak, the pumped storage unit should generate power to reduce the peak; when the load is at its valley, the pumped storage unit should pump water to fill the valley. This represents the lower limit of pumped storage power generation capacity. This is the upper limit of the pumping power for pumped storage power generation; This refers to the power generation of the pumped storage unit; This refers to the pumping capacity of the pumped storage unit; To improve the operating efficiency of pumped storage units; at the same time, the pumping and power generation conditions of pumped storage cannot change abruptly. (6) Load shedding constraint (36) In the formula, is the actual load; is the load after taking the demand response mechanism; is the proportion of abandoned load allowed by the system; (7) Constraints related to carbon capture (37) In the formula: Indicates the unit flooded storage in The volume of the solution at time t; Indicates the unit Solution storage in Release at any time Required solution volume; Indicates the unit The depleted fluid storage in The volume of the solution at time t; This indicates the capacity of the solution storage device, where, The expression is: (38) In the formula: Indicates monoethanolamine molar mass; Represents carbon dioxide molar mass; This indicates the analytical value of the regeneration tower; Indicates the concentration of the alkanolamine solution; This indicates the density of an alkanolamine solution; Since the carbon capture unit was converted from a thermal power unit, the net processing range of the power system after the conversion is constrained as follows: (39) (8) Power balance constraints (40)。 2. The method of claim 1, wherein the method is characterized by, Step S4 is implemented as follows: (1) Ladder-style carbon trading model The carbon trading mechanism is as follows: each unit has a portion of free carbon emission allowances. When its carbon emissions exceed the allocated allowances, it needs to purchase the excess carbon emission allowances from the carbon trading market. Conversely, it can sell the remaining allowances to the carbon trading market to generate revenue. (1.1) Carbon emission model (1) In the formula: This indicates the amount of carbon emissions produced by thermal power units. Indicates the carbon emission intensity of thermal power units; Indicates the output of the thermal power unit; Therefore, the carbon trading volume of thermal power units participating in carbon trading is: (2) In the formula: This indicates the amount of carbon transactions in which thermal power units participate in carbon trading; This represents the carbon emission quota coefficient for thermal power units; (1.2) Ladder-style carbon trading model Tiered carbon trading divides carbon emission allowances into multiple trading zones at equal intervals. As the amount of carbon emission allowances to be purchased increases, the corresponding carbon trading price also increases, thereby promoting energy conservation and emission reduction. The tiered carbon trading model is as follows: (3) In the formula: Indicates carbon trading costs, Indicates the base price for carbon trading. Indicates the length of the carbon trading range. Indicates the rate of increase in carbon trading prices; (2) Mathematical model of carbon capture power plant The total output of a carbon capture power plant after the low-carbon retrofit of thermal power units is divided into two parts: net output and capture energy consumption. Capture energy consumption is further divided into stationary energy consumption and operational energy consumption. The absorption energy consumption within the operational energy consumption is negligible. The mathematical model for the carbon capture power plant is as follows: (4) In the formula: Indicates the unit The flue gas split ratio; Indicates the data captured by the crew Total amount; This indicates the amount of solution storage capacity available for the unit to be captured. quantity; For carbon capture efficiency; This refers to the maximum operating condition coefficient of the regeneration tower and compressor; To maximize the technical output of the generator unit; Energy consumption for the operation of carbon capture units; For the collection unit Energy consumption; This refers to the net output of the thermal power unit. This refers to the fixed energy consumption of the carbon capture unit.

Images