Calculation method of renewable energy output simultaneity rate for power grid system

Abstract

The present invention discloses a method for calculating the simultaneous output rate of new energy for a power grid system, including obtaining historical wind power output data and historical photovoltaic output data of a target power grid system; calculating the simultaneous output rate of wind power for the target power grid system, the simultaneous output rate of photovoltaic for the target power grid system, and the simultaneous output rate of wind power-photovoltaic for the target power grid system; finally, calculating the simultaneous output rate of new energy for the target power grid. The method for calculating the simultaneous output rate of new energy for a power grid system provided by the present invention innovatively considers the output state of new energy for the power grid and the power abandonment state, and proposes a comprehensive, new and accurate method for calculating the simultaneous output rate of new energy; therefore, the method of the present invention has good accuracy, high reliability and good practicality.

Description

Technical Field

[0001] The invention belongs to the field of electrical automation, and in particular relates to a method for calculating a new energy output simultaneity rate for a power grid system. 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] At present, environmental problems are becoming increasingly prominent, so new energy power generation systems have developed rapidly, and new energy power generation systems have also begun to be incorporated into the existing power grid system in large quantities. At present, the scale of new energy installed capacity has exceeded the limit that the current power grid system can absorb, and the phenomenon of new energy abandonment is frequent, and wind and solar resources are seriously wasted. As the proportion of wind and solar power generation installed capacity in the total installed capacity of the power grid increases, the problem of intermittent output and poor temporal and spatial matching of power grid load has become increasingly prominent, the peak-to-valley difference of the equivalent load of the power grid has greatly increased, and there are problems with the grid transmission in some new energy-intensive areas, and the situation of new energy absorption in the power grid has become increasingly severe.

[0004] Since the construction period of power grid engineering is long, while the construction period of new energy power generation projects is short, it is necessary to consider in advance whether the future planned grid can meet the demand for new energy transmission under the boundary conditions of future new energy installed capacity in the power grid planning. If it cannot be met, the power grid system can timely propose grid reinforcement projects and promote their early implementation; however, unreasonable estimates will result in low utilization of grid reinforcement projects, resulting in a large amount of waste of power grid company data. Therefore, it is urgent to study how to reasonably consider the output of new energy in the planning of power grid, that is, the simultaneous output rate of new energy, so as to reasonably evaluate the energy consumption problem of future new energy power generation systems.

[0005] However, the current calculation method of the simultaneous output rate of new energy generally uses the confidence interval method to solve the simultaneous output rate of new energy: the analysis data is arranged from large to small according to the simultaneous rate, the first 5% of the data points are removed, and then the simultaneous rate corresponding to the first point of the remaining data points is used as the simultaneous output rate of new energy. However, this method is not very accurate in calculation and leaves a very large margin; this makes the practicality of the current calculated simultaneous output rate of new energy poor. Summary of the invention

[0006] The purpose of the present invention is to provide a method for calculating the simultaneous output rate of renewable energy for a power grid system with good accuracy, high reliability and good practicability.

[0007] The method for calculating the simultaneous output rate of renewable energy for a power grid system provided by the present invention comprises the following steps:

[0008] S1. Obtain historical wind power output data and historical photovoltaic output data of the target power grid system;

[0009] S2. Calculate the wind power output synchronization rate of the target power grid system based on the historical wind power output data obtained in step S1;

[0010] S3. Calculate the photovoltaic output simultaneous rate of the target power grid system based on the historical photovoltaic output data obtained in step S1;

[0011] S4. Calculate the wind power-photovoltaic output simultaneity rate of the target power grid system based on the historical wind power output data and the historical photovoltaic output data obtained in step S1;

[0012] S5. Calculate the new energy output simultaneity rate of the final target power grid based on the wind power output simultaneity rate calculated in step S2, the photovoltaic output simultaneity rate calculated in step S3, and the wind power-photovoltaic output simultaneity rate calculated in step S4.

[0013] Step S2, according to the historical wind power output data obtained in step S1, calculates the wind power output synchronization rate of the target power grid system, and specifically includes the following steps:

[0014] A. Obtain wind power output data every 15 minutes from 0:00 to 7:00 every day in a year; 29 sets of data per day, a total of 10,585 sets of data for the whole year; form the wind power output data set wind out For wind out =[w1,w2,…,w 10585 ], where w i is the wind output value of the ith data point;

[0015] B. Wind power output dataset obtained according to step A out , calculate the simultaneity rate of each data point and obtain the preliminary simultaneity rate array wind of wind power percentage For wind percentage =[a1,a2,…,a 10585 ], where a i is the wind power synchronization rate of the ith data point, and S wind,i is the system wind power installed capacity of the i-th data point;

[0016] C. The wind power preliminary synchronization rate array wind obtained in step B percentage Sort the elements in from large to small to get the wind power simultaneous rate array wind range For wind range=[b1,b2,…,b 10585 ]; then the wind power output dataset wind out The elements in the wind power synchronization rate array wind range Sort the elements in and get the wind power output array wind' out for wind' out =[w′1,w′2,…,w′ 10585 ]; where w′ i Wind is the wind power synchronization rate array range The i-th element b in i The corresponding wind power output value;

[0017] D. Calculate the total wind power generation W of the system throughout the year wind for Where P wind,j is the system wind power output value of the jth data point, Δt is the time interval and its value is 0.25 hours;

[0018] E. Calculate the system’s annual wind power curtailment ΔW wind for Where λ w The wind power synchronization rate array wind range Select the wind power synchronization rate obtained; when calculating, if and only if ΔW wind The cumulative calculation is performed, otherwise no cumulative calculation is performed;

[0019] F. Calculate the wind power curtailment rate η of the system wind for

[0020] G. Wind power abandonment rate η obtained in step F wind Make a judgment:

[0021] If η wind ≤ε wind , then select the minimum wind power synchronization rate λ that meets the requirements w ;

[0022] If η wind >ε wind , then return to step E and recalculate;

[0023] ε wind is the set wind power curtailment rate threshold;

[0024] H. The wind power synchronization rate λ obtained in step G w , as the ultimate target grid system's wind power output synchronization rate.

[0025] The step S3 of calculating the photovoltaic output synchronization rate of the target power grid system based on the historical photovoltaic output data obtained in step S1 specifically includes the following steps:

[0026] a. Obtain PV output data every 15 minutes from 12:00 to 14:00 every day in a year; 9 sets of data per day, a total of 3285 sets of data for the whole year; compose the PV output data set PV out PV out =[p1,p2,…,p 3285 ], where p i is the photovoltaic output value of the i-th data point;

[0027] b. Photovoltaic output data set PV obtained according to step a out , calculate the simultaneity rate of each data point and obtain the photovoltaic preliminary simultaneity rate array PV percentage PV percentage =[c1,c2,…,c 3285 ], where c i is the photovoltaic simultaneity rate of the i-th data point, and S pv,i is the system photovoltaic installed capacity of the i-th data point;

[0028] c. The photovoltaic preliminary synchronization rate array PV obtained in step b percentage Sort the elements in from large to small to get the photovoltaic simultaneous rate array PV range PV range =[d1,d2,…,d 3285 ]; then the photovoltaic output data set PV out The elements in the PV array are calculated according to the photovoltaic synchronization rate. percentage Sort the elements in and get the photovoltaic output array PV′ out PV′ out =[p′1,p′2,…,p′ 3285 ]; where p′ i PV is the photovoltaic array simultaneity rate range The i-th element d in i The corresponding photovoltaic output value;

[0029] d. Calculate the total photovoltaic power generation W of the system throughout the year PV for Where P PV,j is the system PV output value at the jth data point, Δt is the time interval and its value is 0.25 hours;

[0030] e. Calculate the system’s annual photovoltaic power abandonment ΔW PV for Where λ pAccording to the photovoltaic synchronization rate array PV range Select the obtained photovoltaic synchronization rate; when calculating, if and only if ΔW PV The cumulative calculation is performed, otherwise no cumulative calculation is performed;

[0031] f. Calculate the system's photovoltaic power abandonment rate η PV for

[0032] g. The photovoltaic power abandonment rate η obtained in step f PV Make a judgment:

[0033] If η PV ≤ε PV , then select the minimum photovoltaic synchronization rate λ that meets the requirements p ;

[0034] If η PV >ε PV , then return to step e and recalculate;

[0035] ε PV is the set PV power abandonment rate threshold;

[0036] h. The photovoltaic simultaneous rate λ obtained in step g p , as the ultimate target grid system's photovoltaic output synchronization rate.

[0037] Step S4, according to the historical wind power output data and the historical photovoltaic output data acquired in step S1, calculates the wind power-photovoltaic output simultaneity rate of the target power grid system, and specifically includes the following steps:

[0038] (1) Obtain wind and solar power output data every 15 minutes from 0:00 to 7:00 and from 12:00 to 14:00 every day of the year; 38 sets of data per day, a total of 13,870 sets of data throughout the year; constitute the wind and solar power output data set WP out For WP out =[wp1,wp2,…,wp 13870 ], where wp i is the wind and solar power output value of the i-th data point;

[0039] (2) The wind and solar power output dataset WP obtained according to step (1) out , calculate the simultaneity rate of each data point and obtain the preliminary simultaneity rate array WP of wind and solar percentage For WP percentage =[e1,e2,…,e 13870 ], where e i is the wind-solar simultaneous rate of the ith data point, and S WP,iis the system wind and solar installed capacity of the i-th data point;

[0040] (3) The preliminary wind-solar synchronization rate array WP obtained in step (2) percentage Sort the elements in from large to small to get the wind-solar simultaneous rate array WP range For WP range =[f1,f2,…,f 13870 ]; then the wind and solar power output data set WP out The elements in the wind and solar simultaneous rate array WP range Sort the elements in and get the wind and solar power output array WP′ out WP′ out =[wp′1,wp′2,…,wp′ 13870 ]; where wp′ i WP is the wind and solar simultaneous rate array range The i-th element f in i The corresponding wind and solar output value;

[0041] (4) Calculate the total wind and solar power generation of the system throughout the year W WP for Where P WP,j is the system wind and solar output value of the jth data point, Δt is the time interval and its value is 0.25 hours;

[0042] (5) Calculate the system's annual wind and solar power curtailment ΔW WP for Where λ WP WP array based on the wind and solar simultaneous rate range Select the wind power-photovoltaic synchronization rate obtained; when calculating, if and only if ΔW WP The cumulative calculation is performed, otherwise no cumulative calculation is performed;

[0043] (6) Calculate the wind and solar curtailment rate η of the system WP for

[0044] (7) The wind and solar power abandonment rate η obtained in step (6) WP Make a judgment:

[0045] If η WP ≤ε WP , then select the minimum wind power-photovoltaic synchronization rate λ that meets the requirements WP ;

[0046] If η WP >ε WP , then return to step (5) and recalculate;

[0047] εwind is the set wind and solar power curtailment rate threshold;

[0048] (8) The wind power-photovoltaic synchronization rate λ obtained in step (7) WP , as the ultimate target grid system's wind power-photovoltaic output synchronization rate.

[0049] Step S5, according to the wind power output simultaneity rate calculated in step S2, the photovoltaic output simultaneity rate calculated in step S3 and the wind power-photovoltaic output simultaneity rate calculated in step S4, calculates the final target power grid's new energy output simultaneity rate, specifically including the following steps:

[0050] If the installed capacity of wind turbines in the system is 10 times or more than the installed capacity of photovoltaic power in the system, the synchronous rate of renewable energy output of the target power grid is selected as the synchronous rate of wind power λ w ;

[0051] If the system photovoltaic installed capacity is 10 times or more than the system wind turbine installed capacity, the target grid's new energy output simultaneous rate is selected as the photovoltaic simultaneous rate λ p ;

[0052] Otherwise, the target grid’s renewable energy output synchronism rate is selected as the wind power-photovoltaic synchronism rate λ WP .

[0053] The method for calculating the simultaneous output rate of renewable energy for a power grid system provided by the present invention innovatively considers the renewable energy output state and power abandonment state of the power grid, and proposes a comprehensive, new and accurate method for calculating the simultaneous output rate of renewable energy; therefore, the method of the present invention has good accuracy, high reliability and good practicality. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] Figure 1 It is a schematic diagram of the method flow of the present invention.

[0055] Figure 2 This is a schematic diagram of the distribution of wind power synchronization rate from 0 o'clock to 7 o'clock in 2021 according to an embodiment of the present invention.

[0056] Figure 3 This is a distribution diagram of the wind power synchronization rate in 2021 between 0 o'clock and 7 o'clock and excluding the part greater than 50% according to an embodiment of the present invention.

[0057] Figure 4 This is a distribution diagram of the wind power synchronization rate in 2021 between 0 o'clock and 7 o'clock and excluding the part greater than 35% according to an embodiment of the present invention.

[0058] Figure 5 This is a schematic diagram of the distribution of photovoltaic synchronization rate at 12:00-14:00 in 2021 according to an embodiment of the present invention.

[0059] Figure 6 This is a distribution diagram of the photovoltaic synchronization rate in 2021 between 12:00 and 14:00, excluding the part greater than 35% according to an embodiment of the present invention.

[0060] Figure 7 This is a distribution diagram of the photovoltaic synchronization rate in 2021 between 12:00 and 14:00, excluding the part greater than 22% according to an embodiment of the present invention.

[0061] Figure 8 This is a schematic diagram of the distribution of the wind-solar coupling simultaneity rate at 0:00-7:00 and 12:00-14:00 in 2021 of an embodiment of the present invention.

[0062] Fig. 9 This is a distribution diagram of the wind-solar coupling simultaneity rates in 2021 at 0:00-7:00 and 12:00-14:00, excluding the part greater than 13% of the wind-solar coupling rates of an embodiment of the present invention. DETAILED DESCRIPTION

[0063] like Figure 1 The method flow chart of the present invention is shown as follows: The method for calculating the simultaneous output rate of renewable energy for a power grid system provided by the present invention comprises the following steps:

[0064] S1. Obtain historical wind power output data and historical photovoltaic output data of the target power grid system;

[0065] S2. Calculate the wind power output synchronization rate of the target power grid system according to the historical wind power output data obtained in step S1; specifically, the steps include:

[0066] A. Generally, the period of high output of wind turbines is from 0:00 am to 7:00 am the next day, which is a low-load period for the power system. If the wind turbines have high output at this time, it may lead to wind and power abandonment. Therefore, the calculation of wind turbine output synchronization rate mainly analyzes the data of this period throughout the year.

[0067] Obtain wind power output data every 15 minutes from 0:00 to 7:00 every day in a year; 29 sets of data per day, a total of 10585 sets of data for the whole year; form the wind power output data set wind out For wind out =[w1,w2,…,w 10585 ], where w i is the wind output value of the ith data point;

[0068] B. Wind power output dataset obtained according to step A out , calculate the simultaneity rate of each data point and obtain the preliminary simultaneity rate array wind of wind power percentage For wind percentage =[a1,a2,…,a10585 ], where a i is the wind power synchronization rate of the ith data point, and S wind,i is the system wind power installed capacity of the i-th data point;

[0069] C. The wind power preliminary synchronization rate array wind obtained in step B percentage Sort the elements in from large to small to get the wind power simultaneous rate array wind range For wind range =[b1,b2,…,b 10585 ]; then the wind power output dataset wind out The elements in the wind power synchronization rate array wind range Sort the elements in and get the wind power output array wind' out for wind' out =[w′1,w′2,…,w′1 0585 ]; where w′ i Wind is the wind power synchronization rate array range The i-th element b in i The corresponding wind power output value;

[0070] D. Calculate the total wind power generation W of the system throughout the year wind for Where P wind,j is the system wind power output value of the jth data point, Δt is the time interval and its value is 0.25 hours;

[0071] E. Calculate the system’s annual wind power curtailment ΔW wind for Where λ w The wind power synchronization rate array wind range Select the wind power synchronization rate obtained; when calculating, if and only if ΔW wind The cumulative calculation is performed, otherwise no cumulative calculation is performed;

[0072] F. Calculate the wind power curtailment rate η of the system wind for

[0073] G. The wind power abandonment rate η obtained in step F wind Make a judgment:

[0074] If η wind ≤ε wind , then select the minimum wind power synchronization rate λ that meets the requirements w ;

[0075] If η wind>ε wind , then return to step E and recalculate;

[0076] ε wind is the set wind power curtailment rate threshold;

[0077] H. The wind power synchronization rate λ obtained in step G w , as the ultimate target grid system wind power output simultaneous rate;

[0078] S3. Calculate the photovoltaic output synchronization rate of the target power grid system according to the historical photovoltaic output data obtained in step S1; specifically, the steps include:

[0079] a. Generally, the period of the year when photovoltaic power generation is the largest is between 12 noon and 2 p.m., and for the power system, as the scale of new energy installed capacity increases, the problem of absorbing new energy at noon will become prominent after the superposition of wind and light at noon. If the photovoltaic power generation is large at this time, it may lead to the phenomenon of abandoning light and electricity. Therefore, when calculating the photovoltaic power generation simultaneous rate, the data of this period of the year is mainly analyzed;

[0080] Get the photovoltaic output data every 15 minutes from 12:00 to 14:00 every day in a year; 9 sets of data per day, a total of 3285 sets of data for the whole year; form the photovoltaic output data set PV out PV out =[p1,p2,…,p 3285 ], where p i is the photovoltaic output value of the i-th data point;

[0081] b. Photovoltaic output data set PV obtained according to step a out , calculate the simultaneity rate of each data point and obtain the photovoltaic preliminary simultaneity rate array PV percentage PV percentage =[c1,c2,…,c 3285 ], where c i is the photovoltaic simultaneity rate of the i-th data point, and S pv,i is the system photovoltaic installed capacity of the i-th data point;

[0082] c. The photovoltaic preliminary synchronization rate array PV obtained in step b percentage Sort the elements in from large to small to get the photovoltaic simultaneous rate array PV range PV range =[d1,d2,…,d 3285 ]; then the photovoltaic output data set PV out The elements in the PV array are calculated according to the photovoltaic synchronization rate. percentage Sort the elements in and get the photovoltaic output array PV′ outPV′ out =[p′1,p′2,…,p′ 3285 ]; where p′ i PV is the photovoltaic array simultaneity rate range The i-th element d in i The corresponding photovoltaic output value;

[0083] d. Calculate the total photovoltaic power generation W of the system throughout the year PV for Where P PV,j is the system PV output value at the jth data point, Δt is the time interval and its value is 0.25 hours;

[0084] e. Calculate the system’s annual photovoltaic power abandonment ΔW PV for Where λ p According to the photovoltaic synchronization rate array PV range Select the obtained photovoltaic synchronization rate; when calculating, if and only if ΔW PV The cumulative calculation is performed, otherwise no cumulative calculation is performed;

[0085] f. Calculate the system's photovoltaic power abandonment rate η PV for

[0086] g. The photovoltaic power abandonment rate η obtained in step f PV Make a judgment:

[0087] If η PV ≤ε PV , then select the minimum photovoltaic synchronization rate λ that meets the requirements p ;

[0088] If η PV >ε PV , then return to step e and recalculate;

[0089] ε PV is the set PV power abandonment rate threshold;

[0090] h. The photovoltaic simultaneous rate λ obtained in step g p , as the ultimate target grid system photovoltaic output simultaneous rate;

[0091] S4. Calculate the wind power-photovoltaic output simultaneity rate of the target power grid system according to the historical wind power output data and the historical photovoltaic output data obtained in step S1; specifically, the steps include:

[0092] (1) When the installed capacity of wind power and photovoltaic power is large or one of them is large (the installed capacity difference is not large), the problem of new energy consumption may occur at noon; therefore, it is also necessary to consider the superposition of wind power and photovoltaic output and analyze the new energy consumption;

[0093] Obtain wind and solar power output data every 15 minutes from 0:00 to 7:00 and from 12:00 to 14:00 every day in a year; 38 sets of data per day, a total of 13,870 sets of data for the whole year; constitute the wind and solar power output data set WP out For WP out =[wp1,wp2,…,wp 13870 ], where wp i is the wind and solar power output value of the i-th data point;

[0094] (2) The wind and solar power output dataset WP obtained according to step (1) out , calculate the simultaneity rate of each data point and obtain the preliminary simultaneity rate array WP of wind and solar percentage For WP percentage =[e1,e2,…,e 13870 ], where e i is the wind-solar simultaneous rate of the ith data point, and S WP,i is the system wind and solar installed capacity of the i-th data point;

[0095] (3) The preliminary wind-solar synchronization rate array WP obtained in step (2) percentage Sort the elements in from large to small to get the wind-solar simultaneous rate array WP range For WP range =[f1,f2,…,f 13870 ]; then the wind and solar power output data set WP out The elements in the wind and solar simultaneous rate array WP range Sort the elements in and get the wind and solar power output array WP′ out WP′ out =[wp′1,wp′2,…,wp′ 13870 ]; where wp′ i WP is the wind and solar simultaneous rate array range The i-th element f in i The corresponding wind and solar output value;

[0096] (4) Calculate the total wind and solar power generation of the system throughout the year W WP for Where P WP,j is the system wind and solar output value of the jth data point, Δt is the time interval and its value is 0.25 hours;

[0097] (5) Calculate the system's annual wind and solar power curtailment ΔW WP for Where λ WP WP array based on the wind and solar simultaneous rate range Select the wind power-photovoltaic synchronization rate obtained; when calculating, if and only if ΔW WP The cumulative calculation is performed, otherwise no cumulative calculation is performed;

[0098] (6) Calculate the wind and solar curtailment rate η of the system WP for

[0099] (7) The wind and solar power abandonment rate η obtained in step (6) WP Make a judgment:

[0100] If η WP ≤ε WP , then select the minimum wind power-photovoltaic synchronization rate λ that meets the requirements WP ;

[0101] If η WP >ε WP , then return to step (5) and recalculate;

[0102] ε wind is the set wind and solar power curtailment rate threshold;

[0103] (8) The wind power-photovoltaic synchronization rate λ obtained in step (7) WP , as the ultimate target grid system wind power-photovoltaic output simultaneity rate;

[0104] S5. Calculate the final target power grid's new energy output simultaneity rate based on the wind power output simultaneity rate calculated in step S2, the photovoltaic output simultaneity rate calculated in step S3, and the wind power-photovoltaic output simultaneity rate calculated in step S4; specifically, the following steps:

[0105] When the system's wind power installed capacity is much larger than the photovoltaic installed capacity, the system's power curtailment is mainly wind power curtailment. Therefore, the system wind power output simultaneity rate and curtailment are mainly considered in system analysis and new energy consumption analysis. When the system's photovoltaic installed capacity is much larger than the wind power installed capacity, the system's power curtailment is mainly photovoltaic curtailment. Therefore, the system photovoltaic output simultaneity rate and curtailment are mainly considered in analysis. When the system's wind power installed capacity and photovoltaic installed capacity are not much different, the coupling characteristics of wind power and photovoltaic output should be comprehensively analyzed to calculate the new energy output simultaneity rate and the overall new energy curtailment.

[0106] Therefore, the calculation method of the new energy output simultaneous rate of the final target power grid is:

[0107] If the installed capacity of wind turbines in the system is 10 times or more than the installed capacity of photovoltaic power in the system, the synchronous rate of renewable energy output of the target power grid is selected as the synchronous rate of wind power λ w ;

[0108] If the system photovoltaic installed capacity is 10 times or more than the system wind turbine installed capacity, the target grid's new energy output simultaneous rate is selected as the photovoltaic simultaneous rate λ p ;

[0109] Otherwise, the target grid’s renewable energy output synchronism rate is selected as the wind power-photovoltaic synchronism rate λ WP .

[0110] The method of the present invention is further described below in conjunction with an embodiment:

[0111] Taking a certain area as an example, the simultaneous rates of wind, solar and wind-solar coupling are calculated under two different circumstances: considering a 5% power abandonment rate and a 95% guarantee rate.

[0112] (1) Wind power synchronization rate

[0113] The wind power output data from 0:00 to 7:00 in 2021, which is the period with the largest wind turbine output, is selected. The data is divided into 15-minute intervals. There are 29 sets of data in one day and 10,585 sets of data in the whole year. The corresponding wind power simultaneity rate is calculated and the simultaneity rate is arranged from large to small to obtain a schematic diagram of the wind power simultaneity rate distribution, as shown in the figure below: Figure 2 shown.

[0114] Considering the removal of the output corresponding to the simultaneous rate higher than 50%, the wind power curtailment rate is 4.04%. Continue to calculate until the wind power curtailment rate is close to 5%. Finally, it can be concluded that when all the outputs corresponding to the simultaneous rate higher than 35% are removed, the corresponding wind power curtailment rate is 4.99%. Therefore, considering the case of a wind power curtailment rate of 5%, it is recommended that the wind power simultaneous rate be 35%; Figure 3 and Figure 4 As shown;

[0115] Considering the 95% guarantee rate, the corresponding wind power simultaneous rate is 59%. Therefore, if a higher margin is to be left when planning the power grid, it is recommended that the wind power simultaneous rate be 59%.

[0116] (2) Photovoltaic power generation simultaneity rate

[0117] The photovoltaic power generation output data from 12:00 to 14:00 in 2021, which is the period with the largest photovoltaic power generation output, is selected. The data is divided into 9 groups of data in one day with an interval of 15 minutes, and a total of 3285 groups of data in the whole year. The corresponding photovoltaic output simultaneity rate is calculated, and the simultaneity rate is arranged from large to small to obtain the photovoltaic simultaneity rate distribution diagram, as shown below: Figure 5 shown.

[0118] Considering the removal of the output corresponding to the simultaneous rate higher than 35%, the photovoltaic power abandonment rate is 3.1%. Continue to calculate until the photovoltaic power abandonment rate is close to 5%. Finally, it can be concluded that when all the outputs corresponding to the simultaneous rate higher than 22% are removed, the corresponding photovoltaic power abandonment rate is 4.87%. Therefore, considering the photovoltaic power abandonment rate of 5%, it is recommended that the photovoltaic simultaneous rate be 22%; Figure 6 and Figure 7 As shown;

[0119] Considering the 95% guarantee rate, the corresponding PV simultaneous rate is 58.4%. Therefore, if a higher margin is to be left when planning the power grid, it is recommended that the PV simultaneous rate be 58.4%.

[0120] (3) Wind-solar coupled power generation synchronisation rate

[0121] The wind power and photovoltaic coupling power generation output data from 0:00 to 7:00 in 2021, when wind power output is relatively large, and from 12:00 to 14:00 in 2021, when photovoltaic power generation output is relatively large, are selected. The data is divided into 15-minute intervals. There are 28 sets of data in one day, and 13,870 sets of data in the whole year. The corresponding wind-solar coupling output simultaneity rate is calculated, and the simultaneity rate is arranged from large to small to obtain a schematic diagram of the wind-solar coupling simultaneity rate distribution, as shown in the figure below: Figure 8 shown.

[0122] Considering the removal of the output corresponding to the simultaneous rate higher than 30%, the wind-solar curtailment rate is 3.2%. Continue to calculate until the wind-solar curtailment rate is close to 5%. Finally, it can be concluded that when all the outputs corresponding to the simultaneous rate higher than 13% are removed, the corresponding wind-solar curtailment rate is 5%. Therefore, considering the wind-solar curtailment rate of 5%, it is recommended that the wind-solar coupling simultaneous rate be 13%; if Fig. 9 As shown;

[0123] Considering the 95% guarantee rate, the corresponding wind-solar coupling rate is 15.8%. Therefore, if a higher margin is to be left when planning the power grid, it is recommended that the wind-solar coupling rate be 15.8%.

[0124] (4) Conclusion

[0125] Considering the case of a 5% power abandonment rate, when the system wind power installed capacity is much larger than the photovoltaic installed capacity, the system's new energy abandonment is mainly determined by the wind power output under the small mode, so it is recommended that the wind power simultaneous rate under the small mode be 35%. When the system photovoltaic installed capacity is much larger than the wind power installed capacity, the system's new energy abandonment is mainly determined by the photovoltaic output under the noon operation mode, so it is recommended that the photovoltaic output simultaneous rate under the noon mode be 22%. When the system's wind power and photovoltaic installed capacities are not much different, the coupling characteristics of wind power output and photovoltaic output should be considered when calculating the simultaneous rate, so it is recommended that the simultaneous rate be 13% under the coupling of wind power and photovoltaic output. If you want to leave a higher margin, you can consider selecting the simultaneous rate according to the 95% guarantee rate method.

[0126] The above calculation example shows a method for calculating the simultaneous rate of new energy output that can be used when checking the grid planning of the power grid or making power balance for the planned year. The simultaneous rate obtained under the constraint of 5% power abandonment rate is obviously lower than the simultaneous rate obtained under the condition of 95% guarantee rate. It can be considered that the former reflects the lower limit of the simultaneous rate value, and the margin left is relatively low. If the grid transmission problem is checked on this basis, it should be recommended to implement the grid reinforcement project as soon as possible; the latter leaves a higher margin, but there is also the possibility that the situation considered is too serious. The grid transmission problem checked based on this simultaneous rate may not be an urgent problem to be solved. The simultaneous rate calculation method proposed in the present invention is helpful to derive a planned grid reinforcement plan that needs to be proposed and implemented as soon as possible in the grid verification of the power grid, so as to meet the demand for new energy transmission and improve the new energy absorption capacity; and the method of the present invention has better accuracy, higher reliability and better practicality.

Claims

1. A method for calculating the simultaneous output rate of renewable energy for a power grid system, comprising the following steps: S1. Obtain historical wind power output data and historical photovoltaic output data of the target power grid system; S2. Calculate the wind power output synchronization rate of the target power grid system according to the historical wind power output data obtained in step S1; specifically, the steps include: A. Obtain wind power output data every 15 minutes from 0:00 to 7:00 every day in a year; 29 sets of data per day, a total of 10,585 sets of data for the whole year; form the wind power output data set wind out For wind out =[w1,w2,…,w 10585 ], where w i is the wind output value of the ith data point; B. Wind power output dataset obtained according to step A out , calculate the simultaneity rate of each data point and obtain the preliminary simultaneity rate array wind of wind power percentage For wind percentage =[a1,a2,…,a 10585 ], where a i is the wind power synchronization rate of the ith data point, and S wind,i is the system wind power installed capacity of the i-th data point; C. The wind power preliminary synchronization rate array wind obtained in step B percentage Sort the elements in from large to small to get the wind power simultaneous rate array wind range For wind range =[b1,b2,…,b 10585 ]; then the wind power output dataset wind out The elements in the wind power synchronization rate array wind range Sort the elements in and get the wind power output array wind' out for wind' out =[w1',w'2,…,w1' 0585 ];in, w i ' is the wind power simultaneous rate array wind range The i-th element b in i The corresponding wind power output value; D. Calculate the total wind power generation W of the system throughout the year wind for Where P wind,j is the system wind power output value of the jth data point, Δt is the time interval and its value is 0.25 hours; E. Calculate the system’s annual wind power curtailment ΔW wind for Where λ w The wind power synchronization rate array wind range Select the wind power synchronization rate obtained; when calculating, if and only if ΔW wind The cumulative calculation is performed, otherwise no cumulative calculation is performed; F. Calculate the wind power curtailment rate η of the system wind for G. The wind power abandonment rate η obtained in step F wind Make a judgment: If η wind ≤ε wind , then select the minimum wind power synchronization rate λ that meets the requirements w ; If η wind >ε wind , then return to step E and recalculate; ε wind is the set wind power curtailment rate threshold; H. The wind power synchronization rate λ obtained in step G w , as the ultimate target grid system wind power output simultaneous rate; S3. Calculate the photovoltaic output synchronization rate of the target power grid system according to the historical photovoltaic output data obtained in step S1; specifically, the steps include: a. Obtain PV output data every 15 minutes from 12:00 to 14:00 every day in a year; 9 sets of data per day, a total of 3285 sets of data for the whole year; compose the PV output data set PV out PV out =[p1,p2,…,p 3285 ], where p i is the photovoltaic output value of the i-th data point; b. Photovoltaic output data set PV obtained according to step a out , calculate the simultaneity rate of each data point and obtain the photovoltaic preliminary simultaneity rate array PV percentage PV percentage =[c1,c2,…,c 3285 ], where c i is the photovoltaic simultaneity rate of the i-th data point, and S pv,i is the system photovoltaic installed capacity of the i-th data point; c. The photovoltaic preliminary synchronization rate array PV obtained in step b percentage Sort the elements in from large to small to get the photovoltaic simultaneous rate array PV range PV range =[d1,d2,…,d 3285 ]; then the photovoltaic output data set PV out The elements in the PV array are calculated according to the photovoltaic synchronization rate. percentage Sort the elements in and get the photovoltaic output array PV o ' ut PV o ' ut =[p1',p'2,…,p' 3285 ]; where p i 'is the photovoltaic simultaneous rate array PV range The i-th element d in i The corresponding photovoltaic output value; d. Calculate the total photovoltaic power generation W of the system throughout the year PV for Where P PV,j is the system PV output value at the jth data point, Δt is the time interval and its value is 0.25 hours; e. Calculate the system’s annual photovoltaic power abandonment ΔW PV for Where λ p According to the photovoltaic synchronization rate array PV range Select the obtained photovoltaic synchronization rate; when calculating, if and only if ΔW PV The cumulative calculation is performed, otherwise no cumulative calculation is performed; f. Calculate the system's photovoltaic power abandonment rate η PV for g. The photovoltaic power abandonment rate η obtained in step f PV Make a judgment: If η PV ≤ε PV , then select the minimum photovoltaic synchronization rate λ that meets the requirements p ; If η PV >ε PV , then return to step e and recalculate; ε PV is the set PV power abandonment rate threshold; h. The photovoltaic simultaneous rate λ obtained in step g p , as the ultimate target grid system photovoltaic output simultaneous rate; S4. Calculate the wind power-photovoltaic output simultaneity rate of the target power grid system according to the historical wind power output data and the historical photovoltaic output data obtained in step S1; specifically, the steps include: (1) Obtain wind and solar power output data every 15 minutes from 0:00 to 7:00 and from 12:00 to 14:00 every day of the year; 38 sets of data per day, a total of 13,870 sets of data for the whole year; constitute the wind and solar power output data set WP out For WP out =[wp1,wp2,…,wp 13870 ], where wp i is the wind and solar power output value of the i-th data point; (2) The wind and solar power output dataset WP obtained according to step (1) out , calculate the simultaneity rate of each data point and obtain the preliminary simultaneity rate array WP of wind and solar percentage For WP percentage =[e1,e2,…,e 13870 ], where e i is the wind-solar simultaneous rate of the ith data point, and S WP,i is the system wind and solar installed capacity of the i-th data point; (3) The preliminary wind-solar synchronization rate array WP obtained in step (2) percentage Sort the elements in from large to small to get the wind-solar simultaneous rate array WP range For WP range =[f1,f2,…,f 13870 ]; then the wind and solar power output data set WP out The elements in the wind and solar simultaneous rate array WP range Sort the elements in and get the wind and solar power output array WP o ' ut For WP o ' ut =[wp1',wp'2,…,wp1' 3870 ]; among them, wp i 'For the wind and solar simultaneous rate array WP range The i-th element f in i The corresponding wind and solar output value; (4) Calculate the total wind and solar power generation of the system throughout the year W WP for Where P WP,j is the system wind and solar output value of the jth data point, Δt is the time interval and its value is 0.25 hours; (5) Calculate the system's annual wind and solar power curtailment ΔW WP for Where λ WP WP array based on the wind and solar simultaneous rate range Select the wind power-photovoltaic synchronization rate obtained; when calculating, if and only if ΔW WP The cumulative calculation is performed, otherwise no cumulative calculation is performed; (6) Calculate the wind and solar curtailment rate η of the system WP for (7) The wind and solar power abandonment rate η obtained in step (6) WP Make a judgment: If η WP ≤ε WP , then select the minimum wind power-photovoltaic synchronization rate λ that meets the requirements WP ; If η WP >ε WP , then return to step (5) and recalculate; ε wind is the set wind and solar power curtailment rate threshold; (8) The wind power-photovoltaic synchronization rate λ obtained in step (7) WP , as the ultimate target grid system wind power-photovoltaic output simultaneity rate; S5. Calculate the final target power grid's new energy output simultaneity rate based on the wind power output simultaneity rate calculated in step S2, the photovoltaic output simultaneity rate calculated in step S3, and the wind power-photovoltaic output simultaneity rate calculated in step S4; specifically, the following steps: If the installed capacity of wind turbines in the system is 10 times or more than the installed capacity of photovoltaic power in the system, the synchronous rate of renewable energy output of the target power grid is selected as the synchronous rate of wind power λ w ; If the system photovoltaic installed capacity is 10 times or more than the system wind turbine installed capacity, the target grid's new energy output simultaneous rate is selected as the photovoltaic simultaneous rate λ p ; Otherwise, the target grid’s renewable energy output synchronism rate is selected as the wind power-photovoltaic synchronism rate λ WP .

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