Energy storage configuration planning method based on fire storage combined primary frequency modulation

Abstract

The invention relates to the technical field of primary frequency modulation auxiliary service configuration of a thermal power generating unit, in particular to an energy storage configuration planning method based on fire storage combined primary frequency modulation, which comprises the following steps of: obtaining a primary frequency modulation model of the thermal power generating unit by constructing a unit rotor motion model, a speed regulator model and a steam turbine model; and constructing a primary frequency modulation power shortage calculation model, an energy storage primary frequency modulation model, a fire and energy storage combined primary frequency modulation cost income model and a thermal power generating unit and energy storage combined primary frequency modulation double-layer planning model, and calculating energy storage optimal configuration according to the double-layer planning model.

Description

Background Art

[0002] At present, in most power grids in my country, the frequency regulation task is mainly undertaken by large thermal power and hydropower units, which continuously adjust the unit output power to cope with the deviation of the power grid frequency. However, conventional units are composed of rotating mechanical devices, which are affected by mechanical inertia and wear, and are unable to meet the growing demand for power balance and regulation of the power grid from renewable energy. Because in essence, conventional units are designed to output high power and carry large loads, and their response time lag is long, which is not suitable for participating in the frequency disturbance caused by short-term load fluctuations such as seconds to minutes. On the one hand, conventional units participating in secondary frequency regulation are limited by mechanical inertia and ramp rate, and cannot respond to the action instructions issued by the dispatching center in a timely and accurate manner. On the other hand, the coordinated action of conventional units participating in primary and secondary frequency regulation still needs to be further improved. These limitations will cause conventional units to have a long response time lag to power changes, and cause delays, reversals and deviations in frequency regulation actions. The slow response speed and low response accuracy to power regulation signals will lead to more active hot standby in the frequency operation of the power system.

[0003] As a high-quality frequency regulation resource, energy storage has great potential to be explored in the auxiliary frequency regulation service market. However, current research has not yet conducted more in-depth basic theoretical and applied practical research on energy storage technology in the field of frequency regulation. This situation not only reduces the revenue of thermal power plants, but also weakens the primary frequency regulation capability of thermal power units. Therefore, it is necessary to propose an energy storage configuration planning method based on thermal storage combined with primary frequency regulation to solve the problems in the background technology. Summary of the invention

[0004] The main purpose of the present invention is to provide a method for energy storage configuration planning based on thermal storage combined with primary frequency regulation, which effectively solves the above-mentioned problems mentioned in the background technology.

[0005] The technical solution of the present invention is as follows:

[0006] A method for energy storage configuration planning based on thermal storage combined with primary frequency regulation is proposed. The method includes the following steps:

[0007] S1, construct the unit rotor motion model, speed governor model and steam turbine model to obtain the primary frequency regulation model of the thermal power unit;

[0008] S2. Construct a primary frequency modulation power shortage calculation model;

[0009] S3, constructing an energy storage primary frequency modulation model, wherein the energy storage primary frequency modulation model specifically includes a primary frequency modulation control strategy and a charge state maintenance strategy;

[0010] S4. Construct a cost-benefit model for combined primary frequency regulation with thermal storage;

[0011] S5. Construct a two-level planning model for primary frequency regulation of thermal power units and energy storage, and calculate the optimal configuration of energy storage based on the two-level planning model.

[0012] A further improvement of the present invention is that the construction of the unit rotor motion model in S1 includes the following specific steps:

[0013] S11, constructing an initial model of the unit rotor motion, wherein the specific formula of the initial model of the unit rotor motion is:

[0014]

[0015] Where J is the total moment of inertia of the generator and steam turbine, ω m is the mechanical angular velocity of the rotor, T a is the acceleration torque, T m is the mechanical torque, T e is the electromagnetic torque; for the generator T m and T e is positive; for the motor T m and T e is negative; t is time; the inertia constant H is the kinetic energy at rated speed divided by the system power base value S base ,ω 0m represents the rated angular velocity; ω is the electrical angular velocity of the rotor, ω0 is its rated value, P f is the number of motor pole pairs, f is the grid frequency, and * indicates the per-unit value of the corresponding variable;

[0016] S12. Convert the equation of motion into per unit form, specifically:

[0017]

[0018] S13, introduce the disturbance relationship and consider the initial value T m0 =T e0 , P m0 =P e0 ; When the speed is expressed in per unit value and substituted into ω0 = 1, the following relationship is obtained:

[0019] ΔP m* -ΔP e* =ω0(ΔT m* -ΔT e* )+(T m0* -T e0* )Δω * =ΔT m* -ΔT e*

[0020]

[0021] ΔPe =DΔω+ΔP L ;

[0022] Where ΔP m is the increment of mechanical torque work, ΔP e is the increment of electromagnetic torque work, ΔP L is the power shortage not affected by frequency, D is the damping coefficient of the load, and Δω is the change in rotor speed;

[0023] S14, perform Laplace transformation on the initial model of the unit rotor motion to obtain the final unit rotor motion model, the specific formula is:

[0024] Δω * (s) = Δf * (s)=(ΔP m* (s)-ΔP L* (s)) / (2Hs+D).

[0025] A further improvement of the present invention is that the specific formula for constructing the speed regulator model in S1 is:

[0026]

[0027] Δf=f-50

[0028] Among them, ΔY is the change in the opening of the speed regulator control valve, K G is the unit adjustment power of the thermal power unit, Δf is the frequency deviation, Δf′ is the frequency deviation after Δf is output by the dead zone module, and δ is the unit adjustment coefficient; P Gmax is the upper limit of the unit output, f N is the standard frequency value, 50Hz; T G It is the speed regulator action response time constant; deadzone is the dead zone module.

[0029] A further improvement of the present invention is that the construction of the steam turbine model in S1 comprises the following specific steps:

[0030] S15, constructing an initial model of a steam turbine, wherein the specific formula of the initial model of a steam turbine is:

[0031] Where W = Vρ is the mass of steam in the cylinder, V is the volume of the cylinder, ρ is the density of steam, and Q is the flow rate of the steam mass; Q in is the steam flow rate into the cylinder, Q out is the steam flow rate of the cylinder; P is the steam pressure in the cylinder, P0 is the rated pressure, Q0 is the rated flow rate out of the cylinder; T v is the cylinder time constant;

[0032] S16, performing Laplace transform on the initial model of the steam turbine and taking into account the influence of the steam inlet chamber, the reheater and the control valve, to obtain the final steam turbine model, wherein the specific formula of the Laplace transform is:

[0033]

[0034] The specific formula of the final steam turbine model is:

[0035]

[0036] where F SH 、F H 、F I 、F L is the proportional coefficient of steam work in the unit's ultra-high pressure cylinder, high pressure cylinder, medium pressure cylinder, and low pressure cylinder, T CH is the steam volume time constant, T R1 is the time constant of the primary reheat steam volume, T R2 is the secondary reheat steam volume time constant, T c0 is the crossover tube time constant.

[0037] A further improvement of the present invention is that the specific formula of the primary frequency regulation model of the thermal power unit in S1 is:

[0038] Δf * (s)=(ΔP m* (s)-ΔP L* (s)) / (Ms+D), M=2H

[0039] ΔP m (s)=Gen(s)·Gov(s)·deadzone(Δf).

[0040] A further improvement of the present invention is that the specific formula of the primary frequency modulation power shortage calculation model in S32 is:

[0041] ΔP L* (s)=(Ms+D)Δf * (s)-G equ (s)Δf * (s)

[0042] G equ (s) = G gen (s)·Gov(s)·deadzone(Δf * (s), 0.033 / f N )

[0043] Where G equ is the equivalent primary frequency modulation transfer function of the unit, and Δf is the actual frequency deviation.

[0044] A further improvement of the present invention is that the specific content of the primary frequency modulation control strategy in S3 is:

[0045]

[0046] Δf'=deadzone(Δf,0.03)

[0047]

[0048]

[0049] SOC(s)=SOC0+ΔP B (s) / (3600·E·s)

[0050] SOC min ≤SOC(s)≤SOC max

[0051] Where ΔP B is the actual output power of the battery energy storage system, ΔP B ′ and ΔP B ″ are the initial output command of the battery energy storage system and the output power after considering the charging and discharging efficiency η, K B is the real-time frequency regulation coefficient of the battery energy storage system, T B is the first-order response time constant of the battery energy storage system, T pcs is the response time constant of the first-order link of PCS; Saturation function is a nonlinear saturation function, which limits the energy storage output to the upper and lower limits ±P Bmax Among them, P Bmax is the maximum output (rated output) of the energy storage, the output is positive when the energy storage is discharged, and negative when it is charged; SOC is the state of charge of the energy storage, SOC0 is the initial value of SOC, E is the rated capacity of the energy storage, SOC max , SOC min The upper and lower limits of the state of charge.

[0052] A further improvement of the present invention is that the specific content of the charge state maintenance strategy in S3 is:

[0053]

[0054] Where K Bmax is the maximum frequency regulation coefficient of the battery energy storage system, S is the state of charge, S1, S2, S3, and S4 are SOC constants arranged from small to large, where S1 and S4 are the upper and lower limits of the state of charge of the energy storage system. When S is between S2 and S3, the energy storage frequency regulation coefficient is the largest.

[0055] A further improvement of the present invention is that S4 comprises the following specific steps:

[0056] S41. Calculate the frequency regulation assessment fee F1 within a single day. The calculation formula is:

[0057]

[0058] Where, ΔP(Δf,t) is the theoretical response output change; Δf(t) is the value of the grid frequency exceeding 50±Δfsq at time t, with high frequency being positive and low frequency being negative; δ% is the unit adjustment coefficient; MCR is the rated active output of the unit, and ΔQjY is the integrated power calculated by the primary frequency regulation theory; t 调节 is the time when the grid frequency exceeds 50±Δfsq, with a maximum value of 60 seconds; ΔQsY is the actual integrated power of a frequency regulation action; t0 is the moment when the grid frequency is equal to 50±Δfsq; t 调节1 is 60 seconds; PST is the actual output average value of the generator set within 10 seconds before time t0; PSt is the actual output average value after time t0. 调节 The actual output of the unit within the specified time; F1 is the assessment cost of a frequency regulation action; K 死区调节 is the frequency control dead zone different adjustment coefficients, when the frequency control dead zone is 50±0.033Hz, the value is 1; n is the number of frequency regulation actions that meet the assessment conditions in a single day; ΔQjY i The theoretical calculation of the integrated power for the first frequency modulation action of the i-th time; ΔQsY i is the actual integrated power of the first frequency modulation action for the i-th time; α 一次调频 is the primary frequency modulation assessment coefficient, the value is 1.5; C 并网主体 The monthly transaction price of the current month;

[0059] S42. Calculate the total benefit R over the entire life cycle of energy storage. The specific formula is:

[0060] R=Y b ·(365R d -C op )-C inv -C anc +C r

[0061] R d =F1-F1'-π sell (SOC end -SOC0)

[0062]

[0063] C op,d =C op / 365

[0064] Cinv =c e E+c p P

[0065]

[0066] C r =a(C inv +C op,d )

[0067] Where R is the total benefit of thermal storage combined with primary frequency regulation over the entire life cycle of energy storage, Y b is the energy storage dynamic life; R d is the daily income of thermal power generation combined with primary frequency regulation, F1 is the daily assessment cost of thermal power generation unit single frequency regulation, F1' is the daily assessment cost of thermal power generation combined with primary frequency regulation, π sell is the on-grid electricity price of thermal power units, SOC end is the state of charge of the energy storage at the end of the day; C inv is the energy storage investment cost, where c e is the unit capacity investment cost, c p is the unit power investment cost, E is the rated capacity, P is the rated power; C op is the annual operation and maintenance cost of energy storage, which consists of fixed operation and maintenance cost and variable operation and maintenance cost. is the annual fixed operation and maintenance cost per unit power of the energy storage system, is the variable operation and maintenance cost per unit capacity of the energy storage system; C anc The cost of supporting energy storage facilities is is the auxiliary cost per unit power; is the auxiliary cost per unit capacity; C r is the residual value recovery income of energy storage depreciation, a is the residual value coefficient of energy storage equipment, C op,d The single-day energy storage operation and maintenance cost;

[0068] S43. The specific formula for calculating the dynamic life of energy storage in S42 is:

[0069]

[0070] E r =N r D r E

[0071]

[0072]

[0073] Where D r is the rated discharge depth, and the corresponding number of cycles is N r ;D ais the discharge depth of the actual discharge process, and the corresponding number of cycles is N a ; E r is the total amount of electricity discharged by the energy storage during its service life at the rated discharge depth, E is the rated capacity of the battery energy storage; m DOD is the conversion factor; Ea is the annual discharge capacity converted to the rated discharge depth during the discharge process of different discharge depths in the planned horizontal year; N S is the number of research phases in a year; N D is the number of days in the i-th stage; N is the number of discharge processes experienced on the j-th day of the i-th stage; E bijn , is the discharge capacity of BESS in the nth discharge process on the jth day of the ith stage and the conversion factor corresponding to the actual discharge depth; Y b is the service life of BESS, E r E is the total discharge capacity of the battery energy storage within its service life at the rated discharge depth. a The annual discharge capacity at the rated discharge depth is converted from the discharge process at different discharge depths within the planning level year.

[0074] A further improvement of the present invention is that the two-level programming model in S5 includes an upper-level objective function and a lower-level objective function; the specific formula of the upper-level objective function is:

[0075]

[0076] The specific formula of the lower layer objective function is:

[0077] min f2=-R d

[0078] According to the constraints, the primary frequency regulation model of the unit is adjusted as follows:

[0079] Δf * (s)=(ΔP m* (s)-ΔP L* (s)+ΔP B* (s)) / (Ms+D)

[0080] A further improvement of the present invention is that the two layers of the two-layer programming model in S5 are connected by a particle swarm intelligence algorithm (PSO), and the total benefit within the entire life cycle is set as the fitness function of PSO. The upper layer transmits the energy storage configuration optimized by PSO to the lower layer. Under a given energy storage configuration, simulation is performed according to the set droop control strategy and charge state maintenance strategy to obtain the charging and discharging power of the energy storage at each moment and the grid frequency after adding the energy storage; the lower layer uses simulink simulation in MATLAB to solve, and the obtained objective function value is transmitted back to the upper layer, and the energy storage configuration is continuously optimized by PSO.

[0081] The technical effects of the present invention are as follows:

[0082] A method for planning energy storage configuration based on thermal power generation combined with primary frequency regulation is constructed. The invention obtains the primary frequency regulation model of the thermal power generation unit by constructing the unit rotor motion model, the speed regulator model and the steam turbine model; and constructs the primary frequency regulation power shortage calculation model, the energy storage primary frequency regulation model, the thermal power generation combined with primary frequency regulation cost-benefit model, and the thermal power generation unit and energy storage combined with primary frequency regulation double-layer planning model, and calculates the optimal energy storage configuration according to the double-layer planning model. Taking the maximum benefit of thermal power generation combined with primary frequency regulation as the objective function, considering the present value method and the life loss model of energy storage, the thermal power generation unit, the energy storage primary frequency regulation model and the power shortage calculation model are respectively established. The constructed model can be simulated and solved in MATLAB / simulink to obtain the optimal configuration of energy storage and the grid frequency after adding energy storage, so as to improve the primary frequency regulation capability of the thermal power plant and enhance the grid's resistance to small disturbances. BRIEF DESCRIPTION OF THE DRAWINGS

[0083] Other features, objects and advantages of the present invention will become more apparent from the detailed description of non-limiting embodiments made with reference to the following drawings:

[0084] Figure 1 It is a schematic diagram of the process of the present invention;

[0085] Figure 2 This is a double-layer planning model diagram of the fire storage primary frequency modulation of the present invention;

[0086] Figure 3 It is a simulation module diagram of a thermal power unit of the present invention;

[0087] Figure 4 This is a diagram of the energy storage simulation module of the present invention. DETAILED DESCRIPTION

[0088] The present invention aims to propose an energy storage configuration planning method based on thermal storage combined with primary frequency regulation. By constructing the unit rotor motion model, the speed regulator model and the steam turbine model, the primary frequency regulation model of the thermal power unit is obtained; and the primary frequency regulation power shortage calculation model, the energy storage primary frequency regulation model, the thermal storage combined with primary frequency regulation cost-benefit model, and the double-layer planning model of the thermal power unit and the energy storage combined with primary frequency regulation are constructed, and the optimal energy storage configuration is calculated according to the double-layer planning model. Taking the maximum benefit of the thermal storage combined with primary frequency regulation as the objective function, considering the present value method and the life loss model of energy storage, the thermal power unit, the energy storage primary frequency regulation model and the power shortage calculation model are respectively established. The constructed model can be simulated and solved in MATLAB / simulink to obtain the optimal configuration of energy storage and the grid frequency after adding energy storage, so as to improve the primary frequency regulation capability of the thermal power plant and enhance the grid's resistance to small disturbances.

[0089] Embodiment 1:

[0090] This embodiment proposes a method for energy storage configuration planning based on thermal storage combined with primary frequency regulation, such as Figure 1-Figure 4 As shown, the following specific steps are included:

[0091] S1, construct the unit rotor motion model, speed governor model and steam turbine model to obtain the primary frequency regulation model of the thermal power unit;

[0092] S2. Construct a primary frequency modulation power shortage calculation model;

[0093] S3. Constructing an energy storage primary frequency modulation model, wherein the energy storage primary frequency modulation model specifically includes a primary frequency modulation control strategy and a state of charge maintenance strategy;

[0094] S4. Construct a cost-benefit model for combined primary frequency regulation with thermal storage;

[0095] S5. Construct a two-level planning model for primary frequency regulation of thermal power units and energy storage, and calculate the optimal configuration of energy storage based on the two-level planning model.

[0096] In this embodiment, the construction of the unit rotor motion model in S1 includes the following specific steps:

[0097] S11, constructing an initial model of the unit rotor motion, wherein the specific formula of the initial model of the unit rotor motion is:

[0098]

[0099] Where J is the total moment of inertia of the generator and steam turbine, ω m is the mechanical angular velocity of the rotor, T a is the acceleration torque, T m is the mechanical torque, T e is the electromagnetic torque; for the generator T m and T e is positive; for the motor T m and T e is negative; t is time; the inertia constant H is the kinetic energy at rated speed divided by the system power base value S base ,ω 0m represents the rated angular velocity; ω is the electrical angular velocity of the rotor, ω0 is its rated value, P f is the number of motor pole pairs, f is the grid frequency, and * indicates the per-unit value of the corresponding variable;

[0100] S12. Convert the equation of motion into per unit form, specifically:

[0101]

[0102] S13, introduce the disturbance relationship and consider the initial value T m0 =T e0 , P m0 =P e0 ; When the speed is expressed in per unit value and substituted into ω0 = 1, the following relationship is obtained:

[0103] ΔP m* -ΔP e* =ω0(ΔT m* -ΔT e* )+(T m0* -T e0* )Δω * =ΔT m* -ΔT e*

[0104]

[0105] ΔP e =DΔω+ΔP L ;

[0106] Where ΔP m is the increment of mechanical torque work, ΔP e is the increment of electromagnetic torque work, ΔP L is the power shortage not affected by frequency, D is the damping coefficient of the load, and Δω is the change in rotor speed;

[0107] S14, perform Laplace transformation on the initial model of the unit rotor motion to obtain the final unit rotor motion model, the specific formula is:

[0108] Δω * (s) = Δf * (s)=(ΔP m* (s)-ΔP L* (s)) / (2Hs+D).

[0109] In this embodiment, the specific formula for constructing the speed regulator model in S1 is:

[0110]

[0111] Δf=f-50

[0112] Among them, ΔY is the change in the opening of the speed regulator control valve, K G is the unit adjustment power of the thermal power unit, Δf is the frequency deviation, Δf′ is the frequency deviation after Δf is output by the dead zone module, and d is the unit adjustment coefficient; P Gmax is the upper limit of the unit output, f N is the standard frequency value, 50Hz; T GIt is the speed regulator action response time constant; deadzone is the dead zone module.

[0113] In this embodiment, the construction of the steam turbine model in S1 includes the following specific steps:

[0114] S15, constructing an initial model of a steam turbine, wherein the specific formula of the initial model of a steam turbine is:

[0115]

[0116] Where W = Vρ is the mass of steam in the cylinder, V is the volume of the cylinder, ρ is the density of steam, and Q is the flow rate of the steam mass; Q in is the steam flow rate into the cylinder, Q out is the steam flow rate of the cylinder; P is the steam pressure in the cylinder, P0 is the rated pressure, Q0 is the rated flow rate out of the cylinder; T v is the cylinder time constant;

[0117] S16, performing Laplace transform on the initial model of the steam turbine and taking into account the influence of the steam inlet chamber, the reheater and the control valve, to obtain the final steam turbine model, wherein the specific formula of the Laplace transform is:

[0118]

[0119] The specific formula of the final steam turbine model is:

[0120]

[0121] where F SH 、F H 、F I 、F L is the proportional coefficient of steam work in the unit's ultra-high pressure cylinder, high pressure cylinder, medium pressure cylinder, and low pressure cylinder, T CH is the steam volume time constant, T R1 is the time constant of the primary reheat steam volume, T R2 is the volume time constant of the secondary reheat steam, T c0 is the crossover tube time constant.

[0122] In this embodiment, the specific formula of the primary frequency regulation model of the thermal power unit in S1 is:

[0123] Δf * (s)=(ΔP m* (s)-ΔP L* (s)) / (Ms+D), M=2H

[0124] ΔP m(s)=Gen(s)·Gov(s)·deadzone(Δf).

[0125] In this embodiment, the specific formula of the primary frequency modulation power shortage calculation model in S32 is:

[0126] ΔP L* (s)=(Ms+D)Δf * (s)-G equ (s)Δf * (s)

[0127] G equ (s) = G gen (s)·Gov(s)·deadzone(Δf * (s), 0.033 / f N )

[0128] Where G equ is the equivalent primary frequency modulation transfer function of the unit, and Δf is the actual frequency deviation.

[0129] In this embodiment, the specific content of the primary frequency modulation control strategy in S3 is:

[0130]

[0131] Δf'=deadzone(Δf,0.03)

[0132]

[0133] SOC(s)=SOC0+ΔP B (s) / (3600·E·s)

[0134] SOC min ≤SOC(s)≤SOC max

[0135] Where ΔP B is the actual output power of the battery energy storage system, ΔP B ′ and ΔP B ″ are the initial output command of the battery energy storage system and the output power after considering the charging and discharging efficiency η, K B is the real-time frequency regulation coefficient of the battery energy storage system, T B is the first-order response time constant of the battery energy storage system, T pcs is the response time constant of the first-order link of PCS; Saturation function is a nonlinear saturation function, which limits the energy storage output to the upper and lower limits ±P Bmax Among them, P Bmaxis the maximum output (rated output) of the energy storage, the output is positive when the energy storage is discharged, and negative when it is charged; SOC is the state of charge of the energy storage, SOC0 is the initial value of SOC, E is the rated capacity of the energy storage, SOC max , SOC min The upper and lower limits of the state of charge.

[0136] In this embodiment, the specific content of the charge state maintenance strategy in S3 is:

[0137]

[0138] Where K Bmax is the maximum frequency regulation coefficient of the battery energy storage system, S is the state of charge, S1, S2, S3, and S4 are SOC constants arranged from small to large, where S1 and S4 are the upper and lower limits of the state of charge of the energy storage system. When S is between S2 and S3, the energy storage frequency regulation coefficient is the largest.

[0139] In this embodiment, S4 includes the following specific steps:

[0140] S41. Calculate the frequency regulation assessment fee F1 within a single day. The calculation formula is:

[0141]

[0142] Where, ΔP(Δf,t) is the theoretical response output change; Δf(t) is the value of the grid frequency exceeding 50±Δfsq at time t, with high frequency being positive and low frequency being negative; δ% is the unit adjustment coefficient; MCR is the rated active output of the unit, and ΔQjY is the integrated power calculated by the primary frequency regulation theory; t 调节 is the time when the grid frequency exceeds 50±Δfsq, with a maximum value of 60 seconds; ΔQsY is the actual integrated power of a frequency regulation action; t0 is the moment when the grid frequency is equal to 50±Δfsq; t 调节1 is 60 seconds; PST is the actual output average value of the generator set within 10 seconds before time t0; PSt is the actual output average value after time t0. 调节 The actual output of the unit within the specified time; F1 is the assessment cost of a frequency regulation action; K 死区调节 is the frequency control dead zone different adjustment coefficients, when the frequency control dead zone is 50±0.033Hz, the value is 1; n is the number of frequency regulation actions that meet the assessment conditions in a single day; ΔQjY i The theoretical calculation of the integrated power for the first frequency modulation action of the i-th time; ΔQsY i is the actual integrated power of the first frequency modulation action for the i-th time; α 一次调频 is the primary frequency modulation assessment coefficient, the value is 1.5; C 并网主体 The monthly transaction price of the current month;

[0143] S42. Calculate the total benefit R over the entire life cycle of energy storage. The specific formula is:

[0144] R=Y b ·(365R d -C op )-C inv -C anc +C r

[0145] R d =F1-F1'-π sell (SOC end -SOC0)

[0146]

[0147] C op,d =C op / 365

[0148] C inv =c e E+c p P

[0149]

[0150] C r =a(C inv +C op,d )

[0151] Where R is the total benefit of thermal storage combined with primary frequency regulation over the entire life cycle of energy storage, Y b is the dynamic life of energy storage; R d is the daily income of thermal power generation combined with primary frequency regulation, F1 is the daily assessment cost of thermal power generation unit single frequency regulation, F1' is the daily assessment cost of thermal power generation combined with primary frequency regulation, π sell is the on-grid electricity price of thermal power units, SOC end is the state of charge of the energy storage at the end of the day; C inv is the energy storage investment cost, where c e is the unit capacity investment cost, c p is the unit power investment cost, E is the rated capacity, P is the rated power; C op is the annual operation and maintenance cost of energy storage, which consists of fixed operation and maintenance cost and variable operation and maintenance cost. is the annual fixed operation and maintenance cost per unit power of the energy storage system, is the variable operation and maintenance cost per unit capacity of the energy storage system; C anc The cost of supporting energy storage facilities is is the auxiliary cost per unit power; is the auxiliary cost per unit capacity; C ris the residual value recovery income of energy storage depreciation, a is the residual value coefficient of energy storage equipment, C op,d The single-day energy storage operation and maintenance cost;

[0152] S43. The specific formula for calculating the dynamic life of energy storage in S42 is:

[0153]

[0154] E r =N r D r E

[0155]

[0156] Where D r is the rated discharge depth, and the corresponding number of cycles is N r ;D a is the discharge depth of the actual discharge process, and the corresponding number of cycles is N a ; E r is the total amount of electricity discharged by the energy storage during its service life at the rated discharge depth, E is the rated capacity of the battery energy storage; m DOD is the conversion factor; Ea is the annual discharge capacity converted to the rated discharge depth during the discharge process of different discharge depths in the planned horizontal year; N S is the number of research phases in a year; N D is the number of days in the i-th stage; N is the number of discharge processes experienced on the j-th day of the i-th stage; E bijn , is the discharge capacity of BESS in the nth discharge process on the jth day of the ith stage and the conversion factor corresponding to the actual discharge depth; Y b is the service life of BESS, E r E is the total discharge capacity of the battery energy storage within its service life at the rated discharge depth. a The annual discharge capacity at the rated discharge depth is converted from the discharge process at different discharge depths within the planning level year.

[0157] In this embodiment, the two-level programming model in S5 includes an upper-level objective function and a lower-level objective function; the specific formula of the upper-level objective function is:

[0158]

[0159] The specific formula of the lower layer objective function is:

[0160] min f2=-R d

[0161] According to the constraints, the primary frequency regulation model of the unit is adjusted as follows:

[0162] Δf * (s)=(ΔP m* (s)-ΔP L* (s)+ΔP B* (s)) / (Ms+D)

[0163] In this embodiment, the two layers of the two-layer programming model in S5 are connected by a particle swarm intelligence algorithm (PSO), and the total benefit over the entire life cycle is set as the fitness function of PSO. The upper layer transmits the energy storage configuration optimized by PSO to the lower layer. Under the given energy storage configuration, simulation is performed according to the set droop control strategy and charge state maintenance strategy to obtain the charging and discharging power of the energy storage at each moment and the grid frequency after adding the energy storage; the lower layer uses simulink simulation in MATLAB to solve, and the obtained objective function value is transmitted back to the upper layer, and the energy storage configuration is continuously optimized by PSO.

[0164] Embodiment 2:

[0165] This embodiment provides an electronic device, including: a processor and a memory, wherein the memory stores a computer program that can be called by the processor; the processor executes the above-mentioned energy storage configuration planning method based on thermal storage combined with primary frequency modulation by calling the computer program stored in the memory.

[0166] The electronic device may have relatively large differences due to different configurations or performances, and may include one or more processors (Central Processing Units, CPU) and one or more memories, wherein the memory stores at least one computer program, and the computer program is loaded and executed by the processor to implement a method for energy storage configuration planning based on thermal storage combined with primary frequency modulation provided by the above method embodiment. The electronic device may also include other components for realizing the functions of the device. For example, the electronic device may also have components such as a wired or wireless network interface and an input and output interface to input and output data. This embodiment will not be described in detail here.

[0167] Those skilled in the art know that the present invention can be implemented as a system, method or computer program product. Therefore, the present disclosure can be specifically implemented in the following forms, namely: it can be complete hardware, it can be complete software (including firmware, resident software, microcode, etc.), and it can also be a combination of hardware and software, which is generally referred to as "circuit", "module" or "system" herein. In addition, in some embodiments, the present invention can also be implemented in the form of a computer program product in one or more computer-readable media, and the computer-readable medium contains computer-readable program code.

[0168] Any combination of one or more computer-readable media may be used. A computer-readable medium may be a computer-readable signal medium or a computer-readable storage medium. More specific examples of computer-readable storage media (a non-exhaustive list) include: an electrical connection with one or more wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above. In this document, a computer-readable storage medium may be any tangible medium containing or storing a program that may be used by or in conjunction with an instruction execution system, apparatus, or device.

[0169] The present invention is described with reference to flowcharts and block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process or block in the flowchart and block diagram, as well as the combination of processes and blocks in the flowchart or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowcharts. Figure 1 Process or multiple processes and boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0170] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 Process or multiple processes and boxes Figure 1 The steps for the functions specified in one or more boxes.

[0171] The embodiments of the present invention are described above in conjunction with the accompanying drawings, but the present invention is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the enlightenment of the present invention, ordinary technicians in this field can also make many forms without departing from the scope of protection of the purpose of the present invention and the claims, which all fall within the protection of the present invention.

Claims

1. A method for energy storage configuration planning based on thermal storage combined with primary frequency modulation, characterized in that: The specific steps include: S1, construct the unit rotor motion model, speed governor model and steam turbine model to obtain the primary frequency regulation model of the thermal power unit; S2. Construct a primary frequency modulation power shortage calculation model; S3, constructing an energy storage primary frequency modulation model, wherein the energy storage primary frequency modulation model specifically includes a primary frequency modulation control strategy and a charge state maintenance strategy; S4. Construct a cost-benefit model for combined primary frequency regulation with thermal storage; S5. Construct a two-level planning model for primary frequency regulation of thermal power units and energy storage, and calculate the optimal configuration of energy storage based on the two-level planning model.

2. The energy storage configuration planning method based on thermal storage combined with primary frequency modulation according to claim 1 is characterized by: The construction of the rotor motion model of the unit in S1 includes the following specific steps: S11, constructing an initial model of the unit rotor motion, wherein the specific formula of the initial model of the unit rotor motion is: Where J is the total moment of inertia of the generator and steam turbine, ω m is the mechanical angular velocity of the rotor, T a is the acceleration torque, T m is the mechanical torque, T e is the electromagnetic torque; for the generator T m and T e is positive; for the motor T m and T e is negative; t is time; the inertia constant H is the kinetic energy at rated speed divided by the system power base value S base ,ω 0m Represents the rated angular velocity; ω is the electrical angular velocity of the rotor, ω0 is its rated value, P f is the number of motor pole pairs, f is the grid frequency, and * indicates the per-unit value of the corresponding variable; S12. Convert the equation of motion into per unit form, specifically: S13, introduce the disturbance relationship and consider the initial value T m0 =T e0 , P m0 =P e0 ; When the speed is expressed in per unit value and substituted into ω0 = 1, the following relationship is obtained: ΔP m* -ΔP e* =ω0(ΔT m* -ΔT e* )+(T m0* -T e0* )See * =ΔT m* -ΔT e* ΔP e =DΔω+ΔP L ; Where ΔP m is the increment of mechanical torque work, ΔP e is the increment of electromagnetic torque work, ΔP L is the power shortage not affected by frequency, D is the damping coefficient of the load, and Δω is the change in rotor speed; S14, perform Laplace transformation on the initial model of the unit rotor motion to obtain the final unit rotor motion model, the specific formula is: Δω * (s)=Δf * (s)=(ΔP m* (s)-ΔP L* (s)) / (2Hs+D)。 3. The energy storage configuration planning method based on thermal storage combined with primary frequency modulation according to claim 1 is characterized by: The specific formula for constructing the speed regulator model in S1 is: Δf=f-50 Among them, ΔY is the change in the opening of the speed regulator control valve, K G is the unit adjustment power of the thermal power unit, Δf is the frequency deviation, Δf′ is the frequency deviation after Δf is output by the dead zone module, and d is the unit adjustment coefficient; P Gmax is the upper limit of the unit output, f N is the standard frequency value, 50Hz; T G It is the speed regulator action response time constant; deadzone is the dead zone module.

4. The energy storage configuration planning method based on thermal storage combined with primary frequency modulation according to claim 2 is characterized by: The construction of the steam turbine model in S1 includes the following specific steps: S15, constructing an initial model of a steam turbine, wherein the specific formula of the initial model of a steam turbine is: Where W = Vρ is the mass of steam in the cylinder, V is the volume of the cylinder, ρ is the density of steam, and Q is the flow rate of the steam mass; Q in is the steam flow rate into the cylinder, Q out is the steam flow rate of the cylinder; P is the steam pressure in the cylinder, P0 is the rated pressure, Q0 is the rated flow rate out of the cylinder; T v is the cylinder time constant; S16, performing Laplace transform on the initial model of the steam turbine and taking into account the influence of the steam inlet chamber, the reheater and the control valve, to obtain the final steam turbine model, wherein the specific formula of the Laplace transform is: The specific formula of the final steam turbine model is: where F SH 、F H 、F I 、F L is the proportional coefficient of steam work in the unit's ultra-high pressure cylinder, high pressure cylinder, medium pressure cylinder, and low pressure cylinder, T CH is the steam volume time constant, T R1 is the time constant of the primary reheat steam volume, T R2 is the volume time constant of the secondary reheat steam, T c0 is the crossover tube time constant.

5. The energy storage configuration planning method based on thermal storage combined with primary frequency modulation according to claim 1 is characterized by: The specific formula of the primary frequency regulation model of the thermal power unit in S1 is: Δf * (s)=(ΔP m* (s)-ΔP L *(s)) / (Ms+D),M=2H ΔP m (s)=Gen(s)·Gov(s)·deadzone(Δf)。 6. The energy storage configuration planning method based on thermal storage combined with primary frequency modulation according to claim 1 is characterized by: The specific formula of the primary frequency modulation power shortage calculation model in S32 is: ΔP L* (s)=(Ms+D)Δf * ·(s)-G equ (s)Δf * (s) G equ (s)=G gen (s)·Gov(s)·deadzone(Δf * (s),0.033 / f N ) Where G equ is the equivalent primary frequency modulation transfer function of the unit, and Δf is the actual frequency deviation.

7. The energy storage configuration planning method based on thermal storage combined with primary frequency modulation according to claim 1 is characterized by: The specific content of the primary frequency modulation control strategy in S3 is: Δf'=deadzone(Δf,0.03) SOC(s)=SOC0+ΔP B (s) / (3600·E·s) SOC min ≤SOC(s)≤SOC max Where ΔP B is the actual output power of the battery energy storage system, ΔP B ′ and ΔP B ″ are the initial output command of the battery energy storage system and the output power after considering the charging and discharging efficiency η, K B is the real-time frequency regulation coefficient of the battery energy storage system, T B is the first-order response time constant of the battery energy storage system, T pcs is the response time constant of the first-order link of PCS; Saturation function is a nonlinear saturation function, which limits the energy storage output to the upper and lower limits ±P Bmax Among them, P Bmax is the maximum output (rated output) of the energy storage, the output is positive when the energy storage is discharged, and negative when it is charged; SOC is the state of charge of the energy storage, SOC0 is the initial value of SOC, E is the rated capacity of the energy storage, SOC max , SOC min The upper and lower limits of the state of charge.

8. The energy storage configuration planning method based on thermal storage combined with primary frequency modulation according to claim 1 is characterized by: The specific content of the charge state maintenance strategy in S3 is: Discharge: Charge: Where K Bmax is the maximum frequency regulation coefficient of the battery energy storage system, S is the state of charge, S1, S2, S3, and S4 are SOC constants arranged from small to large, where S1 and S4 are the upper and lower limits of the state of charge of the energy storage system. When S is between S2 and S3, the energy storage frequency regulation coefficient is the largest.

9. The energy storage configuration planning method based on thermal storage combined with primary frequency modulation according to claim 8 is characterized by: The S4 comprises the following specific steps: S41. Calculate the frequency regulation assessment fee F1 within a single day. The calculation formula is: Where, ΔP(Δf,t) is the theoretical response output change; Δf(t) is the value of the grid frequency exceeding 50±Δfsq at time t, with high frequency being positive and low frequency being negative; δ% is the unit adjustment coefficient; MCR is the rated active output of the unit, and ΔQjY is the integrated power calculated by the primary frequency regulation theory; t 调节 is the time when the grid frequency exceeds 50±Δfsq, with a maximum value of 60 seconds; ΔQsY is the actual integrated power of a frequency regulation action; t0 is the moment when the grid frequency is equal to 50±Δfsq; t 调节1 is 60 seconds; PST is the actual output average value of the generator set within 10 seconds before time t0; PSt is the actual output average value after time t0. 调节 The actual output of the unit within a certain period of time; F1 is the assessment fee for a frequency modulation action; K 死区调节 is the frequency control dead zone different adjustment coefficients, when the frequency control dead zone is 50±0.033Hz, the value is 1; n is the number of frequency regulation actions that meet the assessment conditions in a single day; ΔQjY i The theoretical calculation of the integrated power for the first frequency modulation action of the i-th time; ΔQsY i is the actual integrated power of the first frequency modulation action for the i-th time; α 一次调频 is the primary frequency modulation assessment coefficient, the value is 1.5; C 并网主体 The monthly transaction price of the current month; S42. Calculate the total benefit R over the entire life cycle of energy storage. The specific formula is: R=Y b ·(365R d -C op )-C inv -C anc +C r R d =F1-F1'-π sell (SOC end -SOC0) C op,d =C op / 365 C inv =c e E+c p P C r =a(C inv +C op,d ) Where R is the total benefit of thermal storage combined with primary frequency regulation over the entire life cycle of energy storage, Y b is the dynamic life of energy storage; R d is the daily income of thermal power generation combined with primary frequency regulation, F1 is the daily assessment cost of thermal power generation unit single frequency regulation, F1' is the daily assessment cost of thermal power generation combined with primary frequency regulation, π sell is the on-grid electricity price of thermal power units, SOC end is the state of charge of the energy storage at the end of the day; C inv is the energy storage investment cost, where c e is the unit capacity investment cost, c p is the unit power investment cost, E is the rated capacity, P is the rated power; C op is the annual operation and maintenance cost of energy storage, which consists of fixed operation and maintenance cost and variable operation and maintenance cost. is the annual fixed operation and maintenance cost per unit power of the energy storage system, is the variable operation and maintenance cost per unit capacity of the energy storage system; C anc The cost of supporting energy storage facilities is is the auxiliary cost per unit power; is the auxiliary cost per unit capacity; C r is the residual value recovery income of energy storage depreciation, a is the residual value coefficient of energy storage equipment, C op,d The single-day energy storage operation and maintenance cost; S43. The specific formula for calculating the dynamic life of energy storage in S42 is: E r =N r D r E Where D r is the rated discharge depth, and the corresponding number of cycles is N r ;D a is the discharge depth of the actual discharge process, and the corresponding number of cycles is N a ; E r is the total amount of electricity discharged by the energy storage during its service life at the rated discharge depth, E is the rated capacity of the battery energy storage; m DOD is the conversion factor; Ea is the annual discharge capacity converted to the rated discharge depth during the discharge process of different discharge depths in the planned horizontal year; N S is the number of research phases in a year; N D is the number of days in the i-th stage; N is the number of discharge processes experienced on the j-th day of the i-th stage; E bijn , is the discharge capacity of BESS in the nth discharge process on the jth day of the ith stage and the conversion factor corresponding to the actual discharge depth; Y b is the service life of BESS, E r E is the total discharge capacity of the battery energy storage within its service life at the rated discharge depth. a The annual discharge capacity at the rated discharge depth is converted from the discharge process at different discharge depths within the planning level year.

10. The energy storage configuration planning method based on thermal storage combined with primary frequency modulation according to claim 9 is characterized in that: The two-level programming model in S5 includes an upper-level objective function and a lower-level objective function; the specific formula of the upper-level objective function is: The specific formula of the lower layer objective function is: <h2 style=";text-align:left;direction:ltr">min f2=-R<h2 style=";text-align:left;direction:ltr"> d According to the constraints, the primary frequency regulation model of the unit is adjusted as follows: Δf * (s)=(ΔP m* (s)-ΔP L* (s)+ΔP B* (s)) / (Ms+D) 11. The energy storage configuration planning method based on thermal storage combined with primary frequency modulation according to claim 10 is characterized in that: The two layers of the two-layer planning model in S5 are connected by a particle swarm intelligence algorithm (PSO), and the total benefit over the entire life cycle is set as the fitness function of PSO. The upper layer transmits the energy storage configuration optimized by PSO to the lower layer. Under the given energy storage configuration, simulation is performed according to the set droop control strategy and charge state maintenance strategy to obtain the charging and discharging power of the energy storage at each moment and the grid frequency after adding the energy storage; the lower layer uses simulink simulation in MATLAB to solve, and the obtained objective function value is transmitted back to the upper layer, and the energy storage configuration is continuously optimized by PSO.

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