Optimization method of adjustable load capacity of power system based on new energy consumption

Abstract

The present invention discloses a method for optimizing the adjustable load capacity of an electric power system based on the consumption of new energy, including obtaining the operating data of the electric power system to be analyzed; constructing an objective function with the goal of minimizing the adjustable load capacity under the premise that the amount of abandoned new energy meets the set requirements; constructing the constraint conditions of the objective function with the operating rules of the electric power system as constraints; using the linear interpolation method and the perturbation method to solve the objective function to obtain the final optimization result of the adjustable load capacity of the electric power system. The present invention takes the amount of abandoned new energy as a constraint condition, considers the operation strategy of the energy storage system dominated by time-of-use electricity prices, and solves the minimum value of the adjustable load capacity required for the system configuration; therefore, the method of the present invention not only improves the capacity of absorbing new energy and effectively reduces the amount of abandoned new energy, but also has high reliability, good accuracy, and is objective and scientific.

Description

Technical Field

[0001] The present invention belongs to the field of electrical automation, and in particular relates to a method for optimizing the adjustable load capacity of an electric power system based on new energy consumption. Background Art

[0002] With the development of economy and technology and the improvement of people's living standards, electricity has become an indispensable secondary energy source in people's production and life, bringing endless convenience to people's production and life. Therefore, ensuring the stable and reliable supply of electricity has become one of the most important tasks of the power system.

[0003] In recent years, with the large-scale integration of renewable energy into the power grid, the power grid has encountered problems such as large peak-to-valley difference and new energy absorption. In addition, the randomness, volatility and intermittency of new energy have significant characteristics, and the problems of power grid operation and new energy absorption have become prominent.

[0004] New energy sources such as wind power and photovoltaic power are more random and volatile. To maintain the safe operation of the power system itself, higher requirements are placed on flexible resources to support peak load regulation, voltage regulation, and frequency regulation of the power grid. As the proportion of traditional thermal power units gradually decreases, the control mode of traditional power grids that relies on thermal power units for regulation faces the dilemma of insufficient flexible resources. At present, the changes in the energy consumption structure on the user side are also changing in sync with the electronic characteristics of the power supply side. There will be a large number of controllable loads on the power consumption side at this stage and in the future. Involving flexible and adjustable loads in the regulation of the power grid to support the safe and stable operation of the power grid is an effective form of participation of adjustable loads on the user side in the regulation of the power grid; at the same time, this can also improve the level of new energy consumption.

[0005] However, there is currently no research on the calculation of the adjustable load capacity on the user side, which undoubtedly seriously restricts the participation of the adjustable load on the user side in the grid regulation process. Summary of the invention

[0006] The purpose of the present invention is to provide a method for optimizing the adjustable load capacity of an electric power system based on new energy consumption, which is highly reliable, accurate, objective and scientific.

[0007] The method for optimizing the adjustable load capacity of a power system based on new energy consumption provided by the present invention comprises the following steps:

[0008] S1. Obtaining the operating data of the power system to be analyzed;

[0009] S2. On the premise that the amount of abandoned renewable energy meets the set requirements, the objective function is constructed with the minimum adjustable load capacity as the goal;

[0010] S3. Taking the operation rules of the power system as constraints, construct the constraint conditions of the objective function;

[0011] S4. Using the linear interpolation method combined with the perturbation method, under the constraints obtained in step S3, the objective function constructed in step S2 is solved to obtain the final optimization result of the adjustable load capacity of the power system.

[0012] In step S2, under the premise that the amount of abandoned new energy meets the set requirements, the objective function is constructed with the minimum adjustable load capacity as the goal, which specifically includes the following steps:

[0013] The following formula is used as the objective function:

[0014] min F=P ad.load

[0015] Where F is the value of the objective function; P ad.load For adjustable load capacity.

[0016] The step S3 of constructing the constraint conditions of the objective function based on the operation rules of the power system as constraints specifically includes the following steps:

[0017] A. The working conditions of the power system to be analyzed are the unit startup combination and the minimum output constraints of conventional power units under the low-load mode during the flood season;

[0018] B. Use the following formula as the power balance constraint:

[0019] P ab (t)+P RES (t)+P thermal (t)+P hydro (t)+P line (t) = P B (t)+P L (t)+P ad.load (t)

[0020] Where P ab (t) is the additional adjustment power at time t, and P ab (t)>0 means that the power system to be analyzed needs additional power regulation, P ab (t)<0 indicates the abandoned power of new energy in the power system to be analyzed; P RES (t) is the power generation of the renewable energy at time t, and the direction in which the active power flows out from the renewable energy is defined as the positive direction; P thermal (t) is the power generation of the thermal power unit at time t, and it is stipulated that the direction of active power outflow from the unit is the positive direction; P hydro (t) is the power generation of the hydroelectric unit at time t, and it is stipulated that the direction of active power outflow from the unit is the positive direction; P line(t) is the exchange power of the tie line at time t, and it is stipulated that the active power flowing into the power system to be analyzed is in the positive direction; P B (t) is the active power absorbed by the energy storage system at time t, and the direction in which the active power flows to the energy storage system is defined as the positive direction; P L (t) is the system load of the power system to be analyzed at time t, and it is stipulated that the direction of active power flowing to the load is the positive direction; P ad.load (t) is the active power of the adjustable load at time t, and the direction in which the active power flows to the load is defined as the positive direction;

[0021] C. Use the following formula as the energy storage charge state constraint:

[0022] SOC min ≤SOC(t)≤SOC max

[0023] Where SOC min is the lower limit of the state of charge of the energy storage system; SOC(t) is the state of charge of the energy storage system at time t; SOC max is the upper limit of the state of charge of the energy storage system;

[0024] D. Set the peak-flat-valley period of the power system to be analyzed:

[0025] Valley period: time is t 6 ~t 1 ;

[0026] The first flat period: time is t 1 ~t 2 ;

[0027] The first peak period: time is t 2 ~t 3 ;

[0028] The second normal period: time is t 3 ~t 4 ;

[0029] The second peak period: time is t 4 ~t 5 ;

[0030] The third normal period: time is t 5 ~t 6 ;

[0031] In the formula, time point t 1 ~t 6 is a time point set according to the load state of the power system to be analyzed;

[0032] E. Use the following formula as the energy storage system charging and discharging speed constraint:

[0033] W B ≤E B S max

[0034] Where W B E is the charging and discharging power of the energy storage system; B is the capacity of the energy storage system; S max is the maximum charge and discharge rate of the energy storage system;

[0035] F. Use the following formula as the constraint of energy storage capacity:

[0036] E B ≤ηW RES

[0037] Where η is the ratio of energy storage system capacity to new energy installed capacity; W RES Installed capacity for new energy sources;

[0038] G. Use the following formula as the power abandonment constraint:

[0039] ΔP≤ΔP N

[0040] Where ΔP N is the maximum amount of power abandonment allowed by the power system to be analyzed; ΔP is the amount of new energy abandonment in the power system to be analyzed, and P ab (t) is the additional adjustment power at time t and P ab (t)<0.

[0041] The following formula is used to calculate the adjustable power P of the adjustable load of the power system to be analyzed within one day: ad :

[0042] P ad =XαP ad.load

[0043] Where X is the state sequence of whether each load participates in regulation within 24 hours of a day, X = [x 1 ,x 2 ,x 3 ,……,x 22 ,x 23 ,x 24 ], x i is the indicator variable of the adjustable load participating in load regulation at the i-th moment, and x i =0 means that the adjustable load at the i-th moment does not participate in load regulation, x i =1 means that the adjustable load at the i-th moment participates in load regulation, i=1,2,...,24; α is the proportion sequence of the adjustable load participating in regulation within 24 hours a day, α=[α 1,α 2 ,α 3 ,……,α 22 ,α 23 ,α 24 ] T , α i is the proportion of adjustable load participating in regulation at the i-th moment, and α i ∈(a,b), a is the lower limit of the adjustment ratio, b is the upper limit of the adjustment ratio, and α i A positive number indicates an increase in load, α i A negative number indicates a reduced load.

[0044] The following formula is used to calculate the power generation P of the thermal power unit at time t: thermal (t) and the power generation power P of the hydropower unit at time t hydro (t) and P con.total (t):

[0045] P con.total (t) = P thermal (t)+P hydro (t) = λ 1 P total.thermal (t)+λ 2 P total.hdro (t)

[0046] Where P total.thermal (t) is the maximum active power of the thermal power unit in the startup combination; P total.hdro (t) is the maximum active power of the hydropower unit in the startup combination; 1 is the minimum output coefficient of the thermal power unit; 2 It is the minimum output coefficient of the hydropower unit.

[0047] The exchange power P of the tie line at time t is calculated using the following formula: line (t):

[0048] P line (t) = P plan (t)

[0049] Where P plan (t) is the planned value of the interconnection line power.

[0050] The linear interpolation method in step S4 is combined with the perturbation method to solve the objective function constructed in step S2 under the constraint conditions obtained in step S3 to obtain the final optimization result of the adjustable load capacity of the power system, which specifically includes the following steps:

[0051] The linear difference method is used to calculate the system adjustable load P when the difference η between the actual power abandonment and the allowable power abandonment is 0. ad.load.3 for Where P ad.load.1 is the first initial value of the adjustable load of the system obtained by using the linear difference method, P ad.load.2 is the second initial value of the system adjustable load obtained by linear difference method, η 1 To solve the difference between the actual power abandonment and the allowable power abandonment corresponding to the first initial value of the system adjustable load using the linear difference method, η 2 The difference between the actual power abandonment and the allowable power abandonment corresponding to the second initial value of the system adjustable load is solved by the linear difference method;

[0052] In the process of calculating by linear difference method, when the η value is within the set range, the numerical perturbation method is used on the basis of the solution of linear difference method to solve the system adjustable load when η=0;

[0053] The system adjustable load change τ is calculated using the following formula: I The sensitivity of η to change is a I :

[0054]

[0055] Where τ I is the change in the system's adjustable load; η(P ad.load ,τ I ) is the adjustable load of the system at P ad.load On the basis of increasing the change τ I The difference between the actual amount of power abandoned and the amount of power allowed to be abandoned after η(P ad.load ) is the adjustable load of the system, P ad.load The difference between the actual amount of power abandoned and the amount of power allowed abandoned at that time;

[0056] According to the obtained sensitivity a I , use the following formula to calculate η(P ad.load )=0 The system can adjust the load variation:

[0057] η(P ad.load (I+1) )=η(P ad.load (I) )+a I Δp

[0058] Where η(P ad.load (I) ) is the adjustable load during the I-th calculation; Δp is the value of η(P ad.load (I+1) )=0 when the system can adjust the load;

[0059] When the system adjustable load P obtained by two consecutive solutionsad.load When the difference between the two values ​​is within the set range, the system adjustable load P obtained by the last calculation is considered ad.load The final power system can adjust the load capacity optimization results.

[0060] The method for optimizing the adjustable load capacity of the power system based on the consumption of new energy provided by the present invention takes the amount of abandoned power of new energy as a constraint condition, considers the operation strategy of the energy storage system dominated by time-of-use electricity prices, and solves the minimum value of the adjustable load capacity required for the system configuration; therefore, the method of the present invention not only improves the capacity of absorbing new energy and effectively reduces the amount of abandoned power of new energy, but also has high reliability, good accuracy, and is objective and scientific. BRIEF DESCRIPTION OF THE DRAWINGS

[0061] Figure 1 It is a schematic diagram of the method flow of the present invention.

[0062] Figure 2 It is a schematic diagram of an equivalent load curve of a system after deducting the power of conventional power supply and tie line in an embodiment of the present invention.

[0063] Figure 3 Schematic diagram of a system output curve according to an embodiment of the present invention.

[0064] Figure 4 It is a schematic diagram of the system output curve after considering the adjustable load of the present invention. DETAILED DESCRIPTION

[0065] like Figure 1 The method flow diagram of the present invention is shown as follows: the method for optimizing the adjustable load capacity of the power system based on the consumption of new energy provided by the present invention comprises the following steps:

[0066] S1. Obtaining the operating data of the power system to be analyzed;

[0067] S2. On the premise that the amount of abandoned renewable energy meets the set requirements, the objective function is constructed with the minimum adjustable load capacity as the goal; specifically, the steps include:

[0068] The following formula is used as the objective function:

[0069] min F=P ad.load

[0070] Where F is the value of the objective function; P ad.load For adjustable load capacity;

[0071] S3. Taking the operation rules of the power system as constraints, construct the constraint conditions of the objective function; specifically, the steps include:

[0072] A. The working conditions of the power system to be analyzed are the unit startup combination and the minimum output constraints of conventional power units under the low-load mode during the flood season;

[0073] B. Use the following formula as the power balance constraint:

[0074] P ab (t)+P RES (t)+P thermal (t)+P hydro (t)+P line (t) = P B (t)+P L (t)+P ad.load (t)

[0075] Where P ab (t) is the additional adjustment power at time t, and P ab (t)>0 means that the power system to be analyzed needs additional power regulation, P ab (t)<0 indicates the abandoned power of new energy in the power system to be analyzed; P RES (t) is the power generation of the renewable energy at time t, and the direction in which the active power flows out from the renewable energy is defined as the positive direction; P thermal (t) is the power generation of the thermal power unit at time t, and it is stipulated that the direction of active power outflow from the unit is the positive direction; P hydro (t) is the power generation of the hydroelectric unit at time t, and it is stipulated that the direction of active power outflow from the unit is the positive direction; P line (t) is the exchange power of the tie line at time t, and it is stipulated that the active power flowing into the power system to be analyzed is in the positive direction; P B (t) is the active power absorbed by the energy storage system at time t, and the direction in which the active power flows to the energy storage system is defined as the positive direction; P L (t) is the system load of the power system to be analyzed at time t, and it is stipulated that the direction of active power flowing to the load is the positive direction; P ad.load (t) is the active power of the adjustable load at time t, and the direction in which the active power flows to the load is defined as the positive direction;

[0076] In specific implementation, the conventional power supply in the system has different combinations of startup units under different operating modes. Usually, the startup plan is formulated according to the load conditions and will not be adjusted significantly in the short term. Since the output limit of conventional power has an important impact on the consumption of new energy, more serious scenarios should be considered when selecting startup units, that is, units with larger rated power should be selected among the optional units for calculation; thus, the following formula is used to calculate the power generation power P of the thermal power unit at time t thermal (t) and the power generation power P of the hydropower unit at time t hydro(t) and P con.total (t):

[0077] P con.total (t) = P thermal (t)+P hydro (t) = λ 1 P total.thermal (t)+λ 2 P total.hdro (t)

[0078] Where P total.thermal (t) is the maximum active power of the thermal power unit in the startup combination; P total.hdro (t) is the maximum active power of the hydropower unit in the startup combination; 1 is the minimum output coefficient of the thermal power unit; 2 is the minimum output coefficient of the hydropower unit;

[0079] The exchange power P of the tie line at time t is calculated using the following formula: line (t):

[0080] P line (t) = P plan (t)

[0081] Where P plan (t) is the planned value of the tie line power, which can be regarded as a known quantity;

[0082] C. Use the following formula as the energy storage charge state constraint:

[0083] SOC min ≤SOC(t)≤SOC max

[0084] Where SOC min is the lower limit of the state of charge of the energy storage system; SOC(t) is the state of charge of the energy storage system at time t; SOC max is the upper limit of the state of charge of the energy storage system; at the same time, it should be ensured that SOC(0) = SOC(24) = SOC min ;

[0085] D. Set the peak-flat-valley period of the power system to be analyzed:

[0086] Valley period: time is t 6 ~t 1 ;

[0087] The first flat period: time is t 1 ~t 2 ;

[0088] The first peak period: time is t 2 ~t3 ;

[0089] The second normal period: time is t 3 ~t 4 ;

[0090] The second peak period: time is t 4 ~t 5 ;

[0091] The third normal period: time is t 5 ~t 6 ;

[0092] In the formula, time point t 1 ~t 6 is a time point set according to the load state of the power system to be analyzed;

[0093] E. Use the following formula as the energy storage system charging and discharging speed constraint:

[0094] W B ≤E B S max

[0095] Where W B E is the charging and discharging power of the energy storage system; B is the capacity of the energy storage system; S max is the maximum charge and discharge rate of the energy storage system;

[0096] F. Use the following formula as the constraint of energy storage capacity:

[0097] E B ≤ηW RES

[0098] Where η is the ratio of energy storage system capacity to new energy installed capacity; W RES Installed capacity for new energy sources;

[0099] G. Use the following formula as the power abandonment constraint:

[0100] ΔP≤ΔP N

[0101] Where ΔP N is the maximum amount of power abandonment allowed by the power system to be analyzed; ΔP is the amount of new energy abandonment in the power system to be analyzed, and P ab (t) is the additional adjustment power at time t and P ab (t)<0;

[0102] In addition, the following formula is used to calculate the adjustable power P of the adjustable load of the power system to be analyzed within one day: ad :

[0103] P ad =XαP ad.load

[0104] Where X is the state sequence of whether each load participates in regulation within 24 hours of a day, X = [x 1 ,x 2 ,x 3 ,……,x 22 ,x 23 ,x 24 ], x i is the indicator variable of the adjustable load participating in load regulation at the i-th moment, and x i =0 means that the adjustable load at the i-th moment does not participate in load regulation, x i =1 means that the adjustable load at the i-th moment participates in load regulation, i=1,2,...,24; α is the proportion sequence of the adjustable load participating in regulation within 24 hours a day, α=[α 1 ,α 2 ,α 3 ,……,α 22 ,α 23 ,α 24 ] T , α i is the proportion of adjustable load participating in regulation at the i-th moment, and α i ∈(a,b), a is the lower limit of the adjustment ratio, b is the upper limit of the adjustment ratio, and α i A positive number indicates an increase in load, α i A negative number indicates a reduced load;

[0105] S4. Using the linear interpolation method combined with the perturbation method, under the constraint conditions obtained in step S3, the objective function constructed in step S2 is solved to obtain the final optimization result of the adjustable load capacity of the power system; specifically comprising the following steps:

[0106] The linear difference method is used to calculate the system adjustable load P when the difference η between the actual power abandonment and the allowable power abandonment is 0. ad.load.3 for Where P ad.load.1 is the first initial value of the adjustable load of the system obtained by using the linear difference method, P ad.load.2 is the second initial value of the system adjustable load obtained by linear difference method, η 1 To solve the difference between the actual power abandonment and the allowable power abandonment corresponding to the first initial value of the system adjustable load using the linear difference method, η 2 The difference between the actual power abandonment and the allowable power abandonment corresponding to the second initial value of the system adjustable load is solved by the linear difference method;

[0107] In the process of calculating by linear difference method, when the η value is within the set range, the numerical perturbation method is used on the basis of the solution of linear difference method to solve the system adjustable load when η=0;

[0108] The system adjustable load change τ is calculated using the following formula: I The sensitivity of η to change is a I :

[0109]

[0110] Where τ I is the change in the system's adjustable load; η(P ad.load ,τ I ) is the adjustable load of the system at P ad.load On the basis of increasing the change τ I The difference between the actual amount of power abandoned and the amount of power allowed to be abandoned after η(P ad.load ) is the adjustable load of the system, P ad.load The difference between the actual amount of power abandoned and the amount of power allowed abandoned at that time;

[0111] According to the obtained sensitivity a I , use the following formula to calculate η(P ad.load )=0 The system can adjust the load variation:

[0112] η(P ad.load (I+1) )=η(P ad.load (I) )+a I Δp

[0113] Where η(P ad.load (I) ) is the adjustable load during the I-th calculation; Δp is the value of η(P ad.load (I+1) )=0 when the system can adjust the load;

[0114] When the system adjustable load P obtained by two consecutive solutions ad.load When the difference between the two values ​​is within the set range, the system adjustable load P obtained by the last calculation is considered ad.load The final power system can adjust the load capacity optimization results.

[0115] In addition, in the specific implementation, the electricity generated by renewable energy should be consumed in the region first, and the excess electricity should be stored in the energy storage system and used for grid peak load regulation during peak hours. If the energy storage battery is already full during peak hours and cannot fully consume the excess electricity generated by renewable energy, the renewable energy will be abandoned. In order to make full use of the charging and discharging times of the energy storage system, the remaining electricity required for grid peak load regulation during the first peak hour will be provided by the energy storage system during the off-peak hour; the remaining electricity required for grid peak load regulation during the second peak hour will be provided by the energy storage system during the second flat hour.

[0116] The method of the present invention is further described below in conjunction with a specific embodiment:

[0117] Take a regional power grid as an example. The installed capacity of renewable energy in the regional power grid is 800MW, including 500MW of wind power and 300MW of photovoltaic power. Assume that the equivalent load curve of the regional power grid after deducting the minimum output of conventional power sources and the power of the tie line is as follows: Figure 2 As shown. Under normal circumstances, wind power is configured with 15% energy storage, photovoltaic power is configured with 5% energy storage, the system energy storage power and minimum configuration capacity are 90MW / 180MWh, and the utilization hours of the energy storage system are 2.0 hours.

[0118] The time periods of the power grid are shown in Table 1:

[0119] Table 1 Schematic diagram of power grid time division

[0120] Time time Duration (hours) valley 23:00-7:00 8 flat 7:00-10:00 3 peak 10:00-15:00 5 flat 15:00-18:00 3 peak 18:00-21:00 3 flat 21:00-23:00 2

[0121] Without considering the adjustable load, the proposed control strategy can be used to iteratively solve the output curves of the additional adjustment power of the regional power grid, the new energy generation power, the energy storage absorption active power and the equivalent system load power. Figure 3 As shown. As can be seen from the figure, during the low electricity consumption period, the energy storage system uses surplus electricity for charging, releases the stored electricity during the first peak load period, and then uses the second level consumption period for charging, and releases the stored electricity during the second high load period. At this time, the system's additional adjustment power has two situations: greater than 0 and less than. When the additional adjustment power is less than 0, since the conventional power supply has reached the lower limit of output and no longer has the ability to reduce output, it can only abandon power. When the additional adjustment power is greater than 0, it can be regarded as the conventional power supply increasing its output to meet the system power demand when the system active power is insufficient. It can be calculated from the figure below that within 24 hours a day, the system's abandoned power under given conditions is 234.66MWh.

[0122] When considering the time division of the power grid, the system adjustable load participates in the regulation. Assume that the maximum amount of renewable energy abandoned is 120MWh. Assume that the proportion parameters of the adjustable load participating in the regulation are a=-0.3, b=0.3, and the system output curve after considering the adjustable load participating in the regulation is as follows Figure 4 shown.

[0123] X=[1,1,1,1,1,0,0,0,0,0,0,0,0,1,1,0,0,0,1,1,1,0,0,1]

[0124] α=[0.3,0.3,0.3,0.3,0.3,0.3,0.3,0.1,0.1,0.2,0.2,0.2,0.2,0.2,0.2,0,0,0,-0.3,-0.3,-0.3,-0.1,-0.1,0.3] T

[0125] Through program simulation, it can be obtained that the minimum adjustable load is 115MW at this time. The output curve of the system is as follows: Figure 4 At this time, the amount of abandoned renewable energy is 119.6MWh, which meets the constraint condition of abandoned renewable energy.

[0126] According to the above analysis, when the system configuration energy storage ratio is certain, the coordinated operation between source, load and storage can be achieved through power supply regulation, adjustable load and energy storage charging and discharging control. Under the premise of maintaining the balance of power supply and demand and the amount of new energy abandonment within the allowable range, the reasonable and optimized configuration of adjustable loads can fully and effectively improve the new energy consumption capacity and effectively reduce the amount of new energy abandonment.

Claims

1. A method for optimizing adjustable load capacity of a power system based on new energy consumption, comprising the following steps: S1. Obtaining the operating data of the power system to be analyzed; S2. On the premise that the amount of abandoned renewable energy meets the set requirements, the objective function is constructed with the minimum adjustable load capacity as the goal; specifically, the steps include: The following formula is used as the objective function: min F=P ad.load Where F is the value of the objective function; P ad.load For adjustable load capacity; S3. Taking the operation rules of the power system as constraints, construct the constraint conditions of the objective function; specifically, the steps include: A. The working conditions of the power system to be analyzed are the unit startup combination and the minimum output constraints of conventional power units under the low-load mode during the flood season; B. Use the following formula as the power balance constraint: P ab (t)+P RES (t)+P thermal (t)+P hydro (t)+P line (t)=P B (t)+P L (t)+P ad.load (t) Where P ab (t) is the additional adjustment power at time t, and P ab (t)>0 means that the power system to be analyzed needs additional power regulation, P ab (t)<0 indicates the abandoned power of new energy in the power system to be analyzed; P RES (t) is the power generation of the renewable energy at time t, and the direction in which the active power flows out from the renewable energy is defined as the positive direction; P thermal (t) is the power generation of the thermal power unit at time t, and it is stipulated that the direction of active power outflow from the unit is the positive direction; P hydro (t) is the power generation of the hydroelectric unit at time t, and it is stipulated that the direction of active power outflow from the unit is the positive direction; P line (t) is the exchange power of the tie line at time t, and it is stipulated that the active power flowing into the power system to be analyzed is in the positive direction; P B (t) is the active power absorbed by the energy storage system at time t, and the direction in which the active power flows to the energy storage system is defined as the positive direction; P L (t) is the system load of the power system to be analyzed at time t, and it is stipulated that the direction of active power flowing to the load is the positive direction; P ad.load (t) is the active power of the adjustable load at time t, and the direction in which the active power flows to the load is defined as the positive direction; C. Use the following formula as the energy storage charge state constraint: SOC min ≤SOC(t)≤SOC max Where SOC min is the lower limit of the state of charge of the energy storage system; SOC(t) is the state of charge of the energy storage system at time t; SOC max is the upper limit of the state of charge of the energy storage system; D. Set the peak-flat-valley period of the power system to be analyzed: Valley period: time is t6~t1; The first normal period: time is t1~t2; The first peak period: time is t2~t3; The second normal period: time is t3~t4; The second peak period: time is t4~t5; The third normal period: time is t5-t6; Wherein, time points t1 to t6 are time points set according to the load state of the power system to be analyzed; E. Use the following formula as the energy storage system charging and discharging speed constraint: W B ≤E B S max Where W B E is the charging and discharging power of the energy storage system; B is the capacity of the energy storage system; S max is the maximum charge and discharge rate of the energy storage system; F. Use the following formula as the constraint of energy storage capacity: AND B ≤ηW RES Where η is the ratio of energy storage system capacity to new energy installed capacity; W RES Installed capacity for new energy sources; G. Use the following formula as the power abandonment constraint: ΔP≤ΔP N Where ΔP N is the maximum amount of power abandonment allowed by the power system to be analyzed; ΔP is the amount of new energy abandonment in the power system to be analyzed, and P ab (t) is the additional adjustment power at time t and P ab (t)<0; S4. Using the linear interpolation method combined with the perturbation method, under the constraints obtained in step S3, the objective function constructed in step S2 is solved to obtain the final optimization result of the adjustable load capacity of the power system.

2. The method for optimizing the adjustable load capacity of a power system based on new energy consumption according to claim 1 is characterized in that The following formula is used to calculate the adjustable power P of the adjustable load of the power system to be analyzed within one day: ad : P ad =XαP ad.load Where X is the state sequence of whether each load participates in regulation within 24 hours a day, X=[x1,x2,x3,……,x 22 ,x 23 ,x 24 ], x i is the indicator variable of the adjustable load participating in load regulation at the i-th moment, and x i =0 means that the adjustable load at the i-th moment does not participate in load regulation, x i =1 means that the adjustable load at the i-th moment participates in load regulation, i=1,2,...,24; α is the proportion sequence of the adjustable load participating in regulation within 24 hours a day, α=[α1,α2,α3,……,α 22 ,α 23 ,α 24 ] T , α i is the proportion of adjustable load participating in regulation at the i-th moment, and α i ∈(a,b), a is the lower limit of the adjustment ratio, b is the upper limit of the adjustment ratio, and α i A positive number indicates an increase in load, α i A negative number indicates a reduced load.

3. The method for optimizing the adjustable load capacity of a power system based on new energy consumption according to claim 2 is characterized in that The following formula is used to calculate the power generation P of the thermal power unit at time t: thermal (t) and the power generation power P of the hydropower unit at time t hydro (t) and P con.total (t): P con.total (t)=P thermal (t)+P hydro (t)=λ1P total.thermal (t)+λ2P total.hdro (t) Where P total.thermal (t) is the maximum active power of the thermal power unit in the startup combination; P total.hdro (t) is the maximum active power of the hydropower unit in the startup combination; λ1 is the minimum output coefficient of the thermal power unit; λ2 is the minimum output coefficient of the hydropower unit.

4. The method for optimizing the adjustable load capacity of a power system based on the consumption of new energy according to claim 3 is characterized in that The exchange power P of the tie line at time t is calculated using the following formula: line (t): P line (t)=P plan (t) Where P plan (t) is the planned value of the interconnection line power.

5. The method for optimizing the adjustable load capacity of a power system based on new energy consumption according to claim 4 is characterized in that The linear interpolation method in step S4 is combined with the perturbation method to solve the objective function constructed in step S2 under the constraint conditions obtained in step S3 to obtain the final optimization result of the adjustable load capacity of the power system, which specifically includes the following steps: The linear difference method is used to calculate the system adjustable load P when the difference η between the actual power abandonment and the allowable power abandonment is 0. ad.load.3 for Where P ad.load.1 is the first initial value of the adjustable load of the system obtained by using the linear difference method, P ad.load.2 is the second initial value of the system adjustable load obtained by the linear difference method, η1 is the difference between the actual power abandonment and the allowable power abandonment corresponding to the first initial value of the system adjustable load obtained by the linear difference method, η2 is the difference between the actual power abandonment and the allowable power abandonment corresponding to the second initial value of the system adjustable load obtained by the linear difference method; In the process of calculating by linear difference method, when the η value is within the set range, the numerical perturbation method is used on the basis of the linear difference method to solve the system load when η=0; The system adjustable load change τ is calculated using the following formula: I The sensitivity of η to change is a I : Where τ I is the change in the system's adjustable load; η(P ad.load ,τ I ) is the adjustable load of the system at P ad.load On the basis of increasing the change τ I The difference between the actual amount of power abandoned and the amount of power allowed to be abandoned after η(P ad.load ) is the adjustable load of the system, P ad.load The difference between the actual amount of power abandoned and the amount of power allowed abandoned at that time; According to the obtained sensitivity a I , use the following formula to calculate η(P ad.load )=0, the system can adjust the load variation: the(P ad.load (I+1) )=η(P ad.load (I) )+a I Δp Where η(P ad.load (I) ) is the adjustable load during the first calculation; Δp is the time for the I+1th calculation and solution. Let η(P ad.load (I+1) )=0 when the system can adjust the load; When the system adjustable load P obtained by two consecutive solutions ad.load When the difference between the two is within the set range, the system adjustable load P obtained by the last calculation is considered ad.load The final power system can adjust the load capacity optimization results.

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