CN117767349A

CN117767349A - Optimal scheduling and coordination control method and system for wind-solar new energy power station

Info

Publication number: CN117767349A
Application number: CN202311788922.9A
Authority: CN
Inventors: 魏远; 张欢畅; 梁铮; 周祥; 孙旭东
Original assignee: Northwest Electric Power Design Institute of China Power Engineering Consulting Group
Current assignee: Northwest Electric Power Design Institute of China Power Engineering Consulting Group
Priority date: 2023-12-22
Filing date: 2023-12-22
Publication date: 2024-03-26

Abstract

The invention discloses an optimal scheduling and coordination control method and system for a wind-solar new energy power station, wherein the method comprises the following steps: taking a short-term scheduling plan instruction and a wind-light power prediction curve as inputs, and optimally scheduling a wind-light new energy power station tracking plan through scheduling plan instruction allocation and ultra-short-term-real-time rolling scheduling; the wind-solar new energy power station participates in the coordination control of AGC, AVC and primary frequency modulation auxiliary service by taking the AGC, AVC instruction or grid-connected point frequency deviation signal at the power grid side as input and performing echelon cooperative control on active and reactive power sources in the wind-solar new energy power station. The method can meet the daily power generation control requirement of the wind-light new energy power station, improves the operation flexibility and reliability of the wind-light new energy power station, and has guiding significance and practical value in the aspect of scheduling operation of wind-light new energy power generation projects.

Description

Optimal scheduling and coordination control method and system for wind-solar new energy power station

Technical Field

The invention belongs to the technical field of new energy, and particularly relates to an optimal scheduling and coordination control method and system of a wind-solar new energy power station.

Background

The wind power and photovoltaic new energy output has the characteristics of intermittence, volatility and randomness, and brings technical challenges to the dispatching operation of the power system. The battery energy storage system has the advantages of high response speed, high control precision and flexible charge and discharge, and is widely applied to new energy power systems. The battery energy storage system is configured in the wind-light field station, so that the capability of adjusting and controlling the output of the wind-light field station can be improved, and the problem of wind and light abandoning caused by limited output is solved. Therefore, the wind-solar-energy-storage combined new energy power station is an effective scheme for developing wind power and photovoltaic new energy in a large scale in the future.

The wind-solar energy storage combined power station is internally provided with a plurality of active and reactive power adjusting power supplies. During normal operation, wind power and photovoltaic operate in a maximum power tracking mode, wind and light resources are utilized to the maximum extent, maximum active output is realized, energy storage can be used as an active adjusting power supply and a reactive adjusting power supply, and an SVG/SVC unit is used as the reactive adjusting power supply; wind power and photovoltaic can also emergently participate in active and reactive regulation when power station voltage/frequency out-of-limit events occur or participate in electric auxiliary services. According to the operation scene and the target, the wind-solar new energy power station needs to realize optimal scheduling and coordinated control on the comprehensive power generation system comprising various adjustable output power source types.

Disclosure of Invention

Aiming at the application scene and the technical requirements, the invention provides an optimal scheduling and coordination control method and system for a wind-solar new energy power station, which can realize the optimal scheduling and coordination control functions of the wind-solar new energy power station on three time scales of short term, ultra-short term and real time.

In order to achieve the above purpose, the invention adopts the following technical scheme:

in a first aspect, the invention provides an optimized scheduling and coordination control method for a wind-solar new energy power station, which comprises the following steps:

taking a short-term scheduling plan instruction and a wind-light power prediction curve as inputs, and optimally scheduling a wind-light new energy power station tracking plan through scheduling plan instruction allocation and ultra-short-term-real-time rolling scheduling;

the wind-solar new energy power station participates in the coordination control of AGC, AVC and primary frequency modulation auxiliary service by taking the AGC, AVC instruction or grid-connected point frequency deviation signal at the power grid side as input and performing echelon cooperative control on active and reactive power sources in the wind-solar new energy power station.

As a further improvement of the invention, the method for optimizing and dispatching the tracking plan of the wind-solar new energy power station comprises the following steps:

the total instruction distribution link distributes the total power instruction issued by the dispatching center in a wind, light and storage system; and then entering an ultra-short-term-real-time rolling scheduling link of the wind-light new energy power station, calculating a wind-light-storage system preliminary allocation instruction by taking the minimum tracking error as a target and taking the energy storage constraint condition into consideration in an ultra-short-term scheduling stage, adjusting the wind-light-storage system preliminary allocation instruction obtained in the ultra-short-term scheduling stage by taking the wind-light actual measurement power and the wind-light real-time prediction power as input in a real-time control stage, and finally allocating the wind-light-storage real-time power instruction to each subsystem.

As a further improvement of the invention, the method for optimizing and dispatching the tracking plan of the wind-solar new energy power station specifically comprises the following steps:

and executing a total instruction distribution link, wherein the aim of minimum wind and light abandoning is to optimally distribute the scheduling plan execution instruction among wind, light and storage systems, and the distribution strategy is as follows:

(1) the wind and light abandoning at each moment is calculated, and the expression is as follows:

wherein:the abandoned wind quantity of the power station i at the time t is calculated; />Photovoltaic power generation power of the power station i at the time t;the wind power generation power of the power station i at the moment t; />The energy storage and discharge power of the power station i at the time t; />For power station i to store energy at time t, charging power, < >>Distributing the obtained tracking instruction for the power station i at the time t;

(2) according to the wind and light discarding conditions at each moment, the obtained tracking commandAdjusting; when all the combined power stations have no waste wind and waste light or no waste wind and waste light, the combined power stations do not have the same relation>Adjusting; when the wind and light abandoning exists in the individual combined power station, the adjustment mode is as follows: if the number of the abandoned wind and abandoned light field stations is larger than that of the non-abandoned wind and abandoned light field stations, the tracking instructions after the adjustment of all the light field stations are as follows:

if the number of the abandoned wind and abandoned light field stations is smaller than the number of the non-abandoned wind and abandoned light field stations, the tracking instructions after the adjustment of all the light field stations are as follows:

Wherein:tracking instructions after adjustment for the photoelectric station without wind abandoning; />The method comprises the steps of adjusting a pre-tracking instruction for the no-waste-wind-discarding photoelectric station; n is the number of the photoelectric stations without wind abandoning; />Tracking instructions after adjustment for the wind-discarding photoelectric station; />Adjusting a pre-tracking instruction for the wind-discarding and photoelectric station; m is the number of the wind-discarding and photoelectric stations;

in the ultra-short-term scheduling stage, with the aim of minimizing tracking errors and taking energy storage constraint conditions into consideration, calculating preliminary allocation instructions of wind, light and storage systems, wherein the method comprises the following steps:

taking tracking instruction deviation as an objective function, the expression is:

wherein: t is the total scheduling period, t=24 h; t is the optimal scheduling period number, Δt is the scheduling step length, Δt=1h; p (P) _plan,t A tracking instruction issued by the power grid at the moment t; p (P) _PV,t The power of the photovoltaic power generation at the moment t; p (P) _WT,t For the time t wind powerGenerating power;the discharge power stored for the time t;

the constraint conditions include:

(1) Renewable energy power generation output constraint:

wherein,the upper and lower limits of the output power predicted before the wind power day at the moment t are respectively +.>The upper and lower limits of the output power of the photovoltaic solar front prediction at the moment t are respectively set;

(2) Energy storage device constraints:

the energy storage system adopts an ion battery energy storage form, and has maximum charge and discharge power; and the energy storage system can only be in a charging or discharging state at a single moment:

In the method, in the process of the invention,maximum charging power for the energy storage system; />Maximum discharge power of the energy storage system; />Respectively representing the states of energy storage charging and discharging;

during a charge-discharge cycle, the energy of the energy storage device remains balanced:

in the short-term and ultra-short-term scheduling of the tracking plan, solving a scheduling model through a CPLEX solver;

the ultra-short-term-real-time rolling scheduling mode of the wind-solar new energy power station is as follows:

and after the kth ultra-short-term scheduling period is finished, starting to perform real-time scheduling with resolution in the scheduling period until all real-time scheduling is completed, then performing the (k+1) th ultra-short-term scheduling and all real-time scheduling in the period, and finally completing all ultra-short-term scheduling in the same day.

As a further improvement of the invention, in the short-term and ultra-short-term scheduling of the tracking plan, the scheduling model is solved by a CPLEX solver, which comprises the following steps:

the calculation mode of the wind and light adjustable capacity is as follows:

wherein DeltaP _{WT_adj,t} 、ΔP _{PV_adj,t} Wind power and photovoltaic adjustable capacity at the moment t respectively;respectively predicting power of wind power and photovoltaic in real time at the moment t;

after the adjustable capacity of the wind and light is known, the ultra-short-term wind and light output planned value is adjusted in the following adjustment modes:

Wherein P is _{WT_rt,t} Planning out force for the wind power at the moment t in real time; p (P) _{PV_rt,t} Planning out the power for the photovoltaic at the moment t in real time;

according to the current time SOC, the energy storage maximum charge and discharge quantity at the time is calculated according to the following calculation formula:

wherein Δp is the combined output bias; p (P) _{WT_pra,t} 、P _{PV_pra,t} The measured power of wind power and photovoltaic power is respectively; respectively the maximum charge and discharge power in the real-time adjustment process; p (P) _cs Maximum charge and discharge power of the energy storage system; SOC (State of Charge) _EES,low The low power limit value of the energy storage system is set; SOC (State of Charge) _EES,high Is the high power limit value of the energy storage system.

As a further improvement of the invention, the wind-solar new energy power station participates in the coordination control of AGC, AVC and primary frequency modulation auxiliary service, and comprises the following steps: the wind-light storage new energy power station participates in AGC coordination control, the wind-light storage new energy power station participates in AVC coordination control, and the wind-light storage new energy power station participates in primary frequency modulation coordination control;

the wind-solar new energy power station participating in AGC coordination control comprises the following steps:

the wind-solar new energy power station tracking AGC command coordination control process consists of a command issuing link and a unit response link; the command issuing link distributes AGC command target values received by the telecontrol system to all wind power, photovoltaic and energy storage units; the unit response link is to construct an optimized scheduling model with minimum tracking error based on considering unit constraint conditions, reasonably distribute AGC instructions issued by a superior power grid to each unit, and enable the wind-solar new energy power station to jointly output tracking AGC instructions;

The wind-solar new energy power station participating in AVC coordination control comprises the following steps:

the method comprises the steps that wind-light storage new energy power station tracking AVC instruction coordination control takes a voltage value/a power factor of a grid-connected point of a wind-light storage power station as a coordination control object, the coordination control is executed according to a primary station level and a subarray level two-stage control mode, a first level is a wind-light storage primary station level, target values are distributed to wind power units and photovoltaic units according to AVC instruction target values received by a telemechanical system and are delivered to a wind power plant and a photovoltaic monitoring system to be executed, and meanwhile, action sequences and cooperations of SVC/SVG, a main transformer tap and energy storage are considered; the second stage is a wind, light and storage subarray stage, and the reactive power instruction distribution among wind, light and storage units is coordinated according to the active output states and reactive power availability margin;

the wind-solar new energy power station participates in primary frequency modulation coordination control, and comprises the following components:

the wind-solar new energy power station participates in primary frequency modulation, the frequency value of a grid-connected point of the wind-solar new energy power station is used as a coordination control object, and the coordination control process consists of a multi-power echelon cooperative control link and a wind-light sub-array primary frequency modulation control link;

the multi-power echelon cooperative control loop cooperatively sets primary frequency modulation dead zones, hysteresis time and a difference modulation rate threshold value of various power supplies; the primary frequency modulation control links of the wind, light and storage subarrays adopt subarray-level primary frequency modulation control strategies with adjustable proportion, and frequency modulation power among wind, light and storage units is distributed.

As a further improvement of the invention, the optimized scheduling model is an optimized scheduling model taking tracking power deviation as an objective function, and specifically comprises the following steps:

ΔP _S1,t ＝P _plan,t -P _F1,t

wherein P is _F1,t The sum of power generation plans of all power generation units of the combined power generation system in the t moment planning mode is set;the energy storage and discharge power is at the time t; />Storing energy and charging power for the time t; p (P) _cut,t The wind power generation device is used for generating wind power or light power when the wind power and photovoltaic units are in excess operation, and generating wind power or light power when the wind power and photovoltaic units are not enough in output; p (P) _plan,t Planning an output command for the time t; ΔP _S1,t Is tracking bias in the planning mode.

As a further improvement of the invention, the wind-solar new energy power station participates in AVC coordination control, and specifically comprises the following steps:

(1) The method comprises the steps that an AVC (automatic voltage control) of a wind-light storage station receives a power grid dispatching instruction, and reactive power adjustment quantity required by reactive voltage adjustment of the wind-light storage station is automatically calculated;

(2) Collecting signals of fans in all wind fields, units in photovoltaic and energy storage in all photovoltaic fields and reactive compensation equipment; the wind-solar energy storage station determines the adjustment range of each wind power station, each photovoltaic field and each energy storage reactive power in the area, and collects the reactive power emission quantity of each reactive power emission device;

(3) Comparing the reactive power adjustment quantity required by the reactive voltage adjustment of the wind-solar power storage station with the capacity of the SVG/SVC capable of generating reactive power, and if the required reactive power adjustment quantity is larger than the capacity of the SVG/SVC capable of generating reactive power, fully generating the SVG/SVC, and entering the next step; otherwise, reasonably distributing the required reactive power regulation quantity to SVG/SVC; entering step (6);

(4) Comparing the residual required reactive power adjustment amount with the capacity of the energy storage capable of generating reactive power, and if the required reactive power adjustment amount is larger than the capacity of the energy storage capable of generating reactive power, fully generating the energy storage, and entering the next step; otherwise, reasonably distributing the required reactive power adjustment quantity to the energy storage; entering step (6);

(5) Comparing the distributed residual reactive power adjustment quantity with the capacity of the wind field and the light field capable of generating reactive power, and if the residual required reactive power adjustment quantity is larger than the capacity of the wind field and the light field capable of generating reactive power, fully generating wind and light, and entering the next step; otherwise, reasonably distributing the required reactive power adjustment quantity;

(6) The reactive distribution amount is distributed to each field, and each field sends the received control instruction to each unit in the field;

(7) Judging whether the automatic voltage control target is achieved according to whether the required reactive power adjustment quantity reaches or reaches the degree, if so, jumping out, and if not, entering the step (9);

(8) Judging whether the voltage regulated by the steps is in a normal range or not according to the regulated grid-connected point voltage, if so, continuing to judge, and if not, regulating the tap position of the transformer, and further optimizing the voltage;

(9) And finally, judging whether the voltage control target is not reached, if so, entering a fault condition, and if not, carrying out automatic voltage control again.

As a further improvement of the invention, the wind-solar new energy power station participates in primary frequency modulation coordination control, and specifically comprises the following steps:

in a multi-power supply echelon cooperative control link, various types of power supplies participate in primary frequency modulation in a echelon cooperative manner, and the primary frequency modulation of the new energy simulates the primary frequency modulation characteristic of a traditional thermal power generating unit;

the primary frequency modulation control links of the wind, light and storage subarrays adopt a frequency modulation control strategy based on the equal adjustable proportion; according to the modes of the adjustable capacity proportion, the coordination control layer issues a power adjustment instruction delta P received by the photovoltaic subarray i _i The method comprises the following steps:

p in the formula _maxi Is the maximum output of subarray i, P _maxs For the total maximum output of the power station, P _olds To the total active output of the power station before disturbance occurs, P _oldi To the active force of subarray i before disturbance occurs, deltaP _s Total power change amount for the power station.

According to the invention, in the primary frequency modulation characteristic of the new energy source simulating the traditional thermal power generating unit, when the system frequency slightly fluctuates, the energy storage power station participates in primary frequency modulation, the photovoltaic power station participates in primary frequency modulation, and the wind power station participates in primary frequency modulation, so that the cascade cooperative participation of all types of units in primary frequency modulation is realized.

In a second aspect, the invention provides an optimized scheduling and coordination control system of a wind-solar new energy power station, comprising:

the optimal scheduling module is used for optimally scheduling the tracking plan of the wind-solar new energy power station by taking a short-term scheduling plan instruction and a wind-solar power prediction curve as inputs and performing scheduling plan instruction allocation and ultra-short-term real-time rolling scheduling;

and the coordination control module is used for taking an AGC (automatic gain control) command or an AVC command or grid-connected point frequency deviation signal at the power grid side as input, and enabling the wind-light new energy power station to participate in coordination control of AGC, AVC and primary frequency modulation auxiliary service through echelon cooperative control of active and reactive power sources inside the wind-light new energy power station.

Compared with the prior art, the invention has the following advantages:

the invention provides an optimal scheduling and coordination control method of a wind-light storage new energy power station aiming at a large wind-light storage new energy power station on a power generation side, which comprises three time scales of short term (24 h in the future), ultra-short term (15 min-4 h in the future) and real time (0-15 min in the future). Firstly, providing a tracking plan optimizing and scheduling method of a wind-solar new energy power station, wherein a short-term (future 24 h) scheduling plan instruction and a wind-solar power prediction curve are taken as inputs, and the two steps of scheduling plan instruction allocation and ultra-short-term-real-time rolling scheduling are adopted to improve the tracking plan operation effect of the wind-solar new energy power station and reduce the abandoned wind and the abandoned light; secondly, a coordination control method for participation of the wind-solar new energy power station in AGC, AVC and primary frequency modulation auxiliary service is provided, the method takes the frequency deviation signals of grid-side AGC, AVC instructions or grid-connected points as input, and the rapid response and output control functions of the wind-solar new energy power station are realized through the echelon cooperative control of active and reactive power sources in the wind-solar new energy power station. The method can meet the daily power generation control requirement of the wind-light new energy power station, improves the operation flexibility and reliability of the wind-light new energy power station, and has guiding significance and practical value in the aspect of scheduling operation of wind-light new energy power generation projects.

Drawings

FIG. 1 is a diagram of a rolling schedule coordination relationship;

FIG. 2 is a multi-time scale wind-solar new energy power station tracking plan optimization scheduling flow chart;

FIG. 3 is a flow chart of a wind-solar energy storage AGC coordinated control strategy;

FIG. 4 is a flowchart of a wind-solar storage AVC coordination control strategy;

FIG. 5 is a configuration diagram of frequency modulation parameters of various types of units;

FIG. 6 is a graph of a short-term optimized scheduling result of a wind-solar new energy power station;

FIG. 7 is a graph of ultra-short term optimized scheduling results of a wind-solar new energy power station;

FIG. 8 is a graph of the result of participation of a wind-solar new energy power station in AVC control;

fig. 9 is a graph of the result of participation of the wind-solar new energy power station in primary frequency modulation control.

Detailed Description

In order that those skilled in the art will better understand the present invention, a technical solution in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in which it is apparent that the described embodiments are only some embodiments of the present invention, not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the present invention without making any inventive effort, shall fall within the scope of the present invention.

It should be noted that the terms "first," "second," and the like in the description and the claims of the present invention and the above figures are used for distinguishing between similar objects and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used may be interchanged where appropriate such that the embodiments of the invention described herein may be implemented in sequences other than those illustrated or otherwise described herein. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.

The first object of the invention is to provide an optimized scheduling and coordination control method of a wind-solar new energy power station, which comprises the following steps:

According to the method, the AGC and AVC instructions or grid-connected point frequency deviation signals on the power grid side are used as input, and the rapid response and output control functions of the wind-light storage new energy power station are realized through the echelon cooperative control of active and reactive power sources in the wind-light storage new energy power station. The method can meet the daily power generation control requirement of the wind-light new energy power station, improves the operation flexibility and reliability of the wind-light new energy power station, and has guiding significance and practical value in the aspect of scheduling operation of wind-light new energy power generation projects. The specific steps are as follows:

1) Wind-solar new energy power station tracking plan optimizing and dispatching

The wind-solar new energy power station tracking plan optimizing and dispatching process consists of a total instruction distribution link and a rolling dispatching link, wherein the total instruction distribution link distributes a total power instruction issued by a dispatching center in a wind, light and storage system at first, the method realizes a short-term (24 h in future) time scale optimizing and dispatching function, reduces wind and light abandoning and improves the tracking effect of a power generation system; and then entering an ultra-short-term-real-time rolling scheduling link of a wind-light new energy power station, in an ultra-short-term (15 min-4 h in the future) scheduling stage, taking the minimum tracking error as a target, calculating a preliminary distribution instruction of a wind, light and storage system by taking an energy storage constraint condition into consideration, in a real-time (0-15 min in the future) control stage, taking actual measurement power of wind and light and real-time prediction power of wind and light as input, adjusting the preliminary distribution instruction of the wind, light and storage system obtained in the ultra-short-term scheduling stage so as to reduce the influence of the ultra-short-term prediction error, and finally distributing the wind, light and storage real-time power instruction to each subsystem.

2) Wind-solar new energy power station participating in AGC, AVC and primary frequency modulation coordination control

(1) Wind-solar energy storage new energy power station participating in AGC coordination control

The wind-solar new energy power station tracking AGC command coordination control process consists of a command issuing link and a unit response link. The command issuing link scientifically and reasonably distributes the AGC command target value received by the telecontrol system to each wind power, photovoltaic and energy storage unit; the unit response link is to construct an optimized scheduling model with minimum tracking error based on consideration of unit constraint conditions, reasonably distribute AGC instructions issued by a superior power grid to each unit, and finally enable wind-solar new energy power station to combine to output tracking AGC instructions by utilizing the characteristic of rapid energy storage response to improve the response capability of a power generation system as much as possible.

(2) Wind-solar energy storage new energy power station participating in AVC coordination control

The method comprises the steps that wind-light storage new energy power station tracking AVC instruction coordination control takes a voltage value/a power factor of a grid-connected point of a wind-light storage power station as a coordination control object, the coordination control is executed according to a primary station level and a subarray level two-stage control mode, a first level is a wind-light storage primary station level, target values are distributed to wind power units and photovoltaic units according to AVC instruction target values received by a telemechanical system and are delivered to a wind power plant and a photovoltaic monitoring system to be executed, and meanwhile, action sequences and cooperations of SVC/SVG, a main transformer tap and energy storage are considered; and the second stage is a wind, light and storage subarray stage, and the reactive power instruction distribution among wind, light and storage units is coordinated according to the active output states and reactive power availability margin.

(3) Wind-solar energy storage new energy power station participating primary frequency modulation coordination control

The wind-solar new energy power station participates in primary frequency modulation, the frequency value of the grid-connected point of the wind-solar new energy power station is used as a coordination control object, and the coordination control process consists of a multi-power echelon cooperative control link and a wind-light sub-array primary frequency modulation control link. The multi-power echelon cooperative control loop realizes multi-power echelon cooperative participation in primary frequency modulation by cooperatively setting various power primary frequency modulation dead zones, hysteresis time and a difference modulation rate threshold; the primary frequency modulation control links of the wind, light and storage subarrays adopt subarray-level primary frequency modulation control strategies with adjustable proportion, and frequency modulation power distribution among wind, light and storage units is realized.

In summary, according to the calculation steps, the automatic daily power generation control target of the wind-solar new energy power station is realized. The method can meet the daily power generation control requirement of the wind-light new energy power station, improves the operation flexibility and reliability of the wind-light new energy power station, and has guiding significance and practical value in the aspect of scheduling operation of wind-light new energy power generation projects.

The invention is described in further detail below in connection with specific examples:

1) Wind-solar new energy power station tracking plan optimizing and dispatching

The tracking plan scheduling is divided into short-term output planning and ultra-short-term output rolling optimization adjustment, and three time scales of real-time output control are tracked. The short-term output plan is scheduled by using a short-term wind-solar power predicted value, 4 hours are taken as intervals, short-term predicted information is obtained in a rolling mode every 15 minutes, and the output of each unit of the station is reasonably arranged; the ultra-short-term output rolling optimization is adjusted, rolling prediction is carried out every 15min on the basis of short-term output planning, the dispatching result is 4h after each rolling optimization, and the deviation of a power generation plan is gradually reduced; the real-time dispatching stage is executed once every 5min on the basis of ultra-short-term output rolling optimization, and the ultra-short-term dispatching result is updated according to the renewable energy source real-time output.

The first step is to execute the total instruction distribution link, with the aim of minimum wind and light abandoning, and to optimally distribute the scheduling execution instruction among wind, light and storage systems, wherein the distribution strategy is as follows:

wherein:the abandoned wind quantity of the power station i at the time t is calculated; />Photovoltaic power generation power of the power station i at the time t;the wind power generation power of the power station i at the moment t; />The energy storage and discharge power of the power station i at the time t; / >For power station i to store energy at time t, charging power, < >>And (5) distributing the obtained tracking instruction to the power station i at the time t.

(2) According to the wind and light discarding conditions at each moment, the obtained tracking commandAnd (5) adjusting. When all the combined power stations have no waste wind and waste light or no waste wind and waste light, the combined power stations do not have the same relation>And (5) adjusting. When the wind and light abandoning exists in the individual combined power station, the adjustment mode is as follows: if the number of the abandoned wind and abandoned light field stations is larger than that of the non-abandoned wind and abandoned light field stations, the tracking instructions after the adjustment of all the light field stations are as follows:

wherein:tracking instructions after adjustment for the photoelectric station without wind abandoning; />The method comprises the steps of adjusting a pre-tracking instruction for the no-waste-wind-discarding photoelectric station; n is the number of the photoelectric stations without wind abandoning; />Tracking instructions after adjustment for the wind-discarding photoelectric station; />Adjusting a pre-tracking instruction for the wind-discarding and photoelectric station; and m is the number of the wind-discarding photoelectric stations.

And secondly, executing a short-term (24 h) tracking planning algorithm, taking tracking instruction deviation as an objective function, wherein the expression is as follows:

wherein: t is the total scheduling period, t=24 h; t is the optimal scheduling period number, Δt is the scheduling step length, Δt=1h; p (P) _plan,t A tracking instruction issued by the power grid at the moment t; p (P) _PV,t The power of the photovoltaic power generation at the moment t; p (P) _WT,t The wind power generation power is at the moment t;and the discharge power stored at the time t.

The constraint conditions include:

(1) Renewable energy power generation output constraint:

wherein,the upper and lower limits of the output power predicted before the wind power day at the moment t are respectively +.>The upper and lower limits of the output power predicted before the photovoltaic day at the moment t are respectively.

(2) Energy storage device constraints:

the energy storage system adopts an ion battery energy storage mode, the rated power of the energy storage system is 20% of the installed capacity of wind and light, and the duration is 2 hours, namely the maximum charge and discharge power exists in the energy storage system; and the energy storage system can only be in a certain state of charge or discharge at a single moment.

In the method, in the process of the invention,maximum charging power for the energy storage system; />Maximum discharge power of the energy storage system; />Respectively representing the states of energy storage charging and discharging, and taking the values as 0-1 integer variables; the sum of the two state variables at any time t is equal to 1, namely the energy storage can only be one of the charging state or the discharging state at the time t.

The energy of the energy storage device is kept balanced during a charge-discharge cycle, which is typically taken to be 1 day.

In the short-term and ultra-short-term scheduling of the tracking plan, the scheduling model is solved through a CPLEX solver.

The third part executes the ultra-short-time real-time rolling tracking, and the ultra-short-time real-time rolling scheduling coordination scheduling mode is as follows: and after the kth ultra-short-term scheduling period is finished, starting to perform real-time scheduling with 5min as resolution in 4h of the scheduling period until all real-time scheduling of the 4h is completed, then performing the kth+1th ultra-short-term scheduling and all real-time scheduling of the period, and finally completing all ultra-short-term scheduling of the same day. The coordination mode and the scheduling strategy flow of the ultra-short-time real-time rolling scheduling are shown in figure 1. FIG. 1 is a rolling schedule coordination relationship.

Real-time control within this scheduling period is started. Because ultra-short-term prediction needs to be performed on the wind-light output for 4 hours in the future, the prediction accuracy is not high, and the obtained scheduling result has errors with actual conditions. In the real-time control stage, a wind-light real-time predicted value is input by taking 5min as a resolution, and wind-light planned output obtained in the ultra-short-term scheduling process is finely adjusted by utilizing the real-time predicted value, so that the output is increased on the side with adjustable capacity (namely, the part with the real-time predicted value larger than the planned value), and the output is reduced on the side with the adjustable capacity which is negative, because the predicted time window is shortened, the real-time predicted value is basically consistent with the wind-light actual measured value. The adjustment mode can reduce the influence of a large ultra-short-term prediction error on a scheduling result, the process of increasing the adjustable capacity also improves the wind-solar energy absorption, and the economy of system operation is indirectly improved.

The calculation mode of the wind and light adjustable capacity is as follows:

wherein DeltaP _{WT_adj,t} 、ΔP _{PV_adj,t} Wind power and photovoltaic adjustable capacity at the moment t respectively;and respectively predicting power of wind power and photovoltaic at the moment t in real time.

After the wind-solar adjustable capacity is known, the ultra-short-term wind-solar output planned value can be adjusted, and when the photovoltaic adjustable capacity is negative and the wind-solar adjustable capacity is positive, the wind-power output is required to be increased, and the photovoltaic output is required to be reduced; when the wind power adjustable capacity is negative and the photovoltaic adjustable capacity is positive, the photovoltaic output is required to be increased, the wind power output is reduced, and the wind and light real-time planned output is required to be ensured to be smaller than the wind and light real-time predicted power. In either case, the specific adjustment modes are as follows:

wherein P is _{WT_rt,t} Planning out force for the wind power at the moment t in real time; p (P) _{PV_rt,t} And planning out the power for the photovoltaic at the moment t in real time.

In order to avoid that the electric quantity exceeds the SOC limit value instantaneously in the charge and discharge process, the energy storage maximum charge and discharge quantity at the moment is calculated according to the current moment SOC, and the calculation formula is as follows:

wherein Δp is the combined output bias; p (P) _{WT_pra,t} 、P _{PV_pra,t} The measured power of wind power and photovoltaic power is respectively; respectively the maximum charge and discharge power in the real-time adjustment process; p (P) _cs Maximum charge and discharge power of the energy storage system; SOC (State of Charge) _EES,low The low power limit value of the energy storage system is set; SOC (State of Charge) _EES,high To store energyHigh power limit of the system.

Fig. 2 is a flowchart of the optimal scheduling of the wind-solar-energy-storage new energy power station tracking plan, which comprises a short term (24 h), an ultra-short term (4 h in the future) and a real-time (15 min from the future).

The tracking AGC control strategy is mainly divided into the following three cases, as shown in the flow chart of the tracking AGC algorithm in fig. 3, wherein Δp _t For tracking error at time t, P _EES,t The state of charge of the stored energy at time t,for the time t the stored energy charging power value,for t time, energy storage discharge power value, < >>For the upper limit and the lower limit of the energy storage charging and discharging power at the moment t, P _plan,t Planning a force value for the moment t, P _total,t For the actual output value at time t, P _WT,t For the photovoltaic output power at time t, P _PV,t And outputting power for the wind power at the moment t.

Firstly, at the time t, judging the total active power instruction of the tracking AGC and the adjustable active power value of the stored energy, and when the total active power instruction is in the adjustable range of the stored energy, independently executing the tracking AGC program by the stored energy; if the total active power instruction exceeds the energy storage adjustable range, the wind-solar energy storage is combined to bear the task of tracking instructions; if the energy storage is full (empty) at the time t, the wind-solar unit is combined to carry out instruction tracking, and the energy storage does not participate in power adjustment at the moment.

The tracking AGC algorithm of the wind-light-storage combined power generation system aims at compensating the deviation between the wind-light short-term predicted output and the power grid dispatching plan in real time through mutual coordination and cooperation among wind power, photovoltaic and an energy storage system, so that the wind-light-storage combined power generation system tracks the target instruction as much as possible. Therefore, an optimized scheduling model taking tracking power deviation as an objective function is constructed, the total instruction value is scientifically and reasonably distributed to all wind power and photovoltaic units, and the total instruction value is delivered to a wind power plant and a photovoltaic monitoring system for execution, so that the tracking deviation is reduced to the greatest possible extent.

ΔP _S1,t ＝P _plan,t -P _F1,t (13)

In a wind-light storage reactive power control strategy, a first stage is a wind-light storage collection master station, receives a dispatching control instruction issued by a power grid dispatching center, distributes a total target value of a wind-light reactive power mode to each wind power unit and each photovoltaic unit, issues the total target value to a wind power plant and a photovoltaic monitoring system for execution, and simultaneously considers and cooperates with the action sequence and the cooperation of SVC/SVG, a main transformer tap and energy storage; and the second stage is a wind-solar energy storage substation, receives reactive power control instructions of the collecting station and enables each unit in the area to execute scheduling requirements. A control flow chart of the control strategy is shown in fig. 4.

The calculation flow is as follows:

(1) And the AVC of the wind-light storage power station receives the power grid dispatching instruction and automatically calculates reactive power adjustment quantity required by reactive voltage adjustment of the wind-light storage power station.

Total reactive power output reference value of current wind-solar energy storage station:

Q _ref ＝(U _g -U _ref )I _g cosφ _g tanφ _ref (14)

wherein: phi (phi) _ref A reference value for the common junction power factor angle; u (U) _g 、I _g 、cosφ _g And the measured values of grid-connected point voltage, current and power factor are respectively obtained.

(2) And collecting signals of fans in all wind fields, units in photovoltaic and energy storage in all photovoltaic fields and reactive compensation equipment. The wind-solar energy storage station determines the adjustment range of each wind power station, each photovoltaic field and each energy storage reactive power in the area, and collects information such as the reactive power of each reactive power generation device, and the like.

(3) Comparing the reactive power adjustment quantity required by the reactive voltage adjustment of the wind-solar power storage station with the capacity of the SVG/SVC capable of generating reactive power, and if the required reactive power adjustment quantity is larger than the capacity of the SVG/SVC capable of generating reactive power, fully generating the SVG/SVC, and entering the next step; otherwise, the required reactive power regulation quantity is reasonably distributed to the SVG/SVC. And (6) entering a step 6.

(4) Comparing the residual required reactive power adjustment amount with the capacity of the energy storage capable of generating reactive power, and if the required reactive power adjustment amount is larger than the capacity of the energy storage capable of generating reactive power, fully generating the energy storage, and entering the next step; otherwise, the required reactive power adjustment quantity is reasonably distributed to the energy storage. And (6) entering a step 6.

(5) Comparing the distributed residual reactive power adjustment quantity with the capacity of the wind field and the light field capable of generating reactive power, and if the residual required reactive power adjustment quantity is larger than the capacity of the wind field and the light field capable of generating reactive power, fully generating wind and light, and entering the next step; otherwise, the required reactive power adjustment quantity is reasonably distributed.

(6) And distributing the reactive distribution amount to each field, and sending the received control command to each unit in the field by each field.

(7) After the above steps are completed, whether the automatic voltage control target is achieved is judged according to whether the required reactive power adjustment amount reaches or reaches the degree, if so, the program is jumped out, and if not, the step 9 is entered.

(8) And judging whether the voltage regulated by the steps is in a normal range or not according to the voltage of the grid-connected point actually measured after regulation, if so, continuing to judge, and if not, regulating the tap position of the transformer, thereby further optimizing the voltage.

Firstly, in a multi-power supply echelon cooperative control link, various types of power supplies participate in primary frequency modulation in a echelon cooperative manner, the primary frequency modulation of new energy simulates the primary frequency modulation characteristic of a traditional thermal power generating unit, and the corresponding primary frequency modulation response characteristic of a new energy plant station is as follows:

wherein f is frequency; f (f) _N Is rated frequency; f (f) _d For the frequency modulation dead zone, when the frequency deviation is smaller than the frequency modulation dead zone, the primary frequency modulation is not operated, and the active control rights of the station are all of AGC; when the frequency deviation is larger than the frequency modulation dead zone, the new energy station outputs force according to the mode; p (P) _N Is rated power; p (P) ₀ Is the active power initial value; delta% is a difference adjustment coefficient, and is the ratio of the per unit value of the frequency variation to the active variation.

As shown in FIG. 5, the frequency modulation parameters of various types of units are configured. The setting of the primary frequency modulation dead zone range of the wind power plant is generally larger than that of a photovoltaic power station, and the setting of the primary frequency modulation dead zone range of the photovoltaic power station is generally larger than that of an energy storage power station. When the system frequency slightly fluctuates, the energy storage power station participates in primary frequency modulation firstly, the photovoltaic power station participates in primary frequency modulation secondly, and finally the wind power station participates in primary frequency modulation, so that the cascade cooperative participation of all types of units in primary frequency modulation is realized. The echelon cooperative method is also suitable for cooperative frequency modulation with any two types of power supplies.

Secondly, in the primary frequency modulation control link of the wind, light and storage subarrays, an equal adjustable proportion frequency modulation control strategy is adopted, and an adjustable capacity proportion P of the photovoltaic subarrays i is defined _i The method comprises the following steps:

in which P is _maxi The maximum output of the photovoltaic subarray i; p (P) _mini The minimum output of the photovoltaic subarray i; p (P) _Bi Is the actual power of the photovoltaic sub-array i.

In this mode, each photovoltaic subarray has the same adjustable capacity ratio P _i In the range of 0.ltoreq.P _i And is less than or equal to 1. According to the mode of the equal adjustable capacity ratio, assuming that n independent photovoltaic subarrays exist in the photovoltaic power station, the adjustable capacity ratio among the photovoltaic subarrays meets the following relation:

taking the minimum output P of the photovoltaic subarrays i (i=1, 2, …, n) _mini =0, then the above formula can be converted into:

the above formula is simplified, and the following can be obtained:

assuming that the total active output of the photovoltaic power station before disturbance occurs is P _old The active output of the photovoltaic subarray i is P _oldi The sum of the maximum active power output of each photovoltaic subarray is P _max . Let the power variation borne by the photovoltaic subarray i be delta P _i That is, the work issued by the coordination control layer to the photovoltaic subarraysThe total power change amount born by the photovoltaic power station is delta P according to the rate regulation command _s The following constraints can be obtained:

the above formula can be expressed as:

therefore, the following equation can be solved:

According to the method, the power variation and delta P borne by other photovoltaic subarrays in the photovoltaic power station can be sequentially obtained ₁ Can solve for ΔP _s And delta P ₁ Is the relation of:

then, the power adjustment instruction issued by the coordination control layer to the photovoltaic subarray No. 1 is:

similarly, the power adjustment instruction received by the photovoltaic subarray i can be obtained as follows:

the invention is further illustrated by the following examples:

assuming that the wind-solar new energy power station is installed as follows: wind power is 50MW, 8 6.25MW fans are adopted; the photovoltaic power generation system comprises a photovoltaic power generation system, a power generation system and a power generation system, wherein the photovoltaic power generation system adopts 16 photovoltaic power generation units of 3.125 MW; the energy storage system is 20MW/40WM.h, 4 energy storage subarrays with the energy storage system of 5MW/10WM.h are adopted, and the initial SOC is 0.5. The short-term dispatching output plan curve and wind power and photovoltaic power prediction data are used as input data, an optimal dispatching and coordination control algorithm of the wind-solar new energy power station is automatically executed, an optimal dispatching result of a short-term (24 h,15 min/point) time scale is shown in fig. 6, and the dispatching plan curve can be tracked to the maximum extent by controlling wind, light and storage output plans. The optimal scheduling result of the ultra-short term (15 min-4 h,15 min/point in future) time scale is shown in fig. 7.

FIG. 8 shows the participation of a wind-solar energy storage new energy power station in an AVC control result in one day, the AVC control algorithm takes reactive planning instructions (24 h,15 min/point) as input data, and the working state and real-time active output condition of the wind-solar energy storage power station are considered to respectively give reactive output distribution instructions of wind units, light units, storage units and SVG units.

And 9, when the grid-connected point frequency system of the wind-solar new energy power station suddenly rises, the internal power supply of the power station automatically participates in active output distribution result of primary frequency modulation, according to algorithm logic, the dead zone of the energy storage frequency modulation range is minimum, the lag response time is shortest, the primary frequency modulation is preferentially participated in, the photovoltaic power is inferior, the dead zone of the wind-solar frequency range is maximum, the lag response time is longest, the primary frequency modulation is participated in finally, and the active output value of the wind-solar energy storage participating in the primary frequency modulation adopts an equal adjustable proportion frequency modulation control strategy.

According to the embodiment, the invention provides an optimal scheduling and coordination control method and system of a wind-light storage new energy power station aiming at a large wind-light storage, light storage and wind-light storage new energy power station at a power generation side, wherein the method comprises three time scales of short term (24 h in the future), ultra-short term (15 min-4 h in the future) and real time (0-15 min in the future). The method can meet the daily power generation control requirement of the wind-light new energy power station, improves the operation flexibility and reliability of the wind-light new energy power station, and has guiding significance and practical value in the aspect of scheduling operation of wind-light new energy power generation projects.

The invention also provides an optimized dispatching and coordination control system of the wind-solar new energy power station, which comprises the following steps:

A third object of the embodiment of the present invention is to provide an electronic device, which includes a memory, a processor, and a computer program stored in the memory and capable of running on the processor, where the processor implements an optimized scheduling and coordinated control method of the wind-solar new energy power station when executing the computer program.

A fourth object of the embodiment of the present invention is to provide a computer readable storage medium, where a computer program is stored, and when the computer program is executed by a processor, the method for optimizing and controlling the scheduling and coordination of the wind-solar new energy power station is implemented.

It will be appreciated by those skilled in the art that embodiments of the present invention may be provided as a method, system, or computer program product. Accordingly, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present invention may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein.

The present invention is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems) and computer program products according to embodiments of the invention. It will be understood that each flow and/or block of the flowchart illustrations and/or block diagrams, and combinations of flows and/or blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

Finally, it should be noted that: the above embodiments are only for illustrating the technical aspects of the present invention and not for limiting the same, and although the present invention has been described in detail with reference to the above embodiments, it should be understood by those of ordinary skill in the art that: modifications and equivalents may be made to the specific embodiments of the invention without departing from the spirit and scope of the invention, which is intended to be covered by the claims.

Claims

1. The optimal scheduling and coordination control method for the wind-solar new energy power station is characterized by comprising the following steps of:

2. The method for optimizing and coordinating control of a wind-solar new energy power station according to claim 1, wherein the tracking plan optimizing scheduling of the wind-solar new energy power station comprises the following steps:

3. The method for optimizing and coordinating control of the wind-solar new energy power station according to claim 2, wherein the method is characterized by optimizing the wind-solar new energy power station tracking plan, and specifically comprises the following steps:

wherein:the abandoned wind quantity of the power station i at the time t is calculated; />Photovoltaic power generation power of the power station i at the time t; />The wind power generation power of the power station i at the moment t; />The energy storage and discharge power of the power station i at the time t; />For power station i to store energy at time t, charging power, < >>Distributing the obtained tracking instruction for the power station i at the time t;

wherein: t is the total scheduling period, t=24 h; t is the optimal scheduling period number, Δt is the scheduling step length, Δt=1h; p (P) _plan,t A tracking instruction issued by the power grid at the moment t; p (P) _PV,t The power of the photovoltaic power generation at the moment t; p (P) _WT,t The wind power generation power is at the moment t;the discharge power stored for the time t;

the constraint conditions include:

(1) Renewable energy power generation output constraint:

(2) Energy storage device constraints:

in the method, in the process of the invention,maximum charging power for the energy storage system; />Maximum discharge power of the energy storage system; />Separate tableShowing the state of charge and discharge of the stored energy;

4. The method for optimizing and coordinating control of a wind-solar new energy power station according to claim 3, wherein in the short-term and ultra-short-term scheduling of the tracking plan, the scheduling model is solved by a CPLEX solver, comprising:

The calculation mode of the wind and light adjustable capacity is as follows:

5. The optimal scheduling and coordination control method for a wind-solar new energy power station according to claim 1, wherein the wind-solar new energy power station participates in coordination control of AGC, AVC and primary frequency modulation auxiliary service, and the method comprises the following steps: the wind-light storage new energy power station participates in AGC coordination control, the wind-light storage new energy power station participates in AVC coordination control, and the wind-light storage new energy power station participates in primary frequency modulation coordination control;

6. The method for optimizing and coordinating control of the wind-solar new energy power station according to claim 5, wherein the optimizing and dispatching model is an optimizing and dispatching model taking tracking power deviation as an objective function, and specifically comprises the following steps:

ΔP _S1,t ＝P _plan,t -P _F1,t

7. The optimal scheduling and coordination control method for the wind-solar new energy power station according to claim 5, wherein the wind-solar new energy power station participates in AVC coordination control, and specifically comprises:

8. The optimal scheduling and coordination control method for the wind-solar new energy power station according to claim 5, wherein the wind-solar new energy power station participates in primary frequency modulation coordination control, and specifically comprises the following steps:

the primary frequency modulation control links of the wind, light and storage subarrays adopt a frequency modulation control strategy based on the equal adjustable proportion; according to the mode of the equal adjustable capacity proportion, the coordination control layer transmits power received by the photovoltaic subarray iAdjustment command Δp _i The method comprises the following steps:

9. The optimal scheduling and coordination control method for the wind-solar new energy power station is characterized in that in the primary frequency modulation characteristic of the new energy simulated traditional thermal power unit, when the system frequency slightly fluctuates, the energy storage power station participates in primary frequency modulation firstly, the photovoltaic power station participates in primary frequency modulation secondly, and finally the wind power station participates in primary frequency modulation, so that the cascade cooperative participation of all types of units in primary frequency modulation is realized.

10. An optimized scheduling and coordination control system of a wind-solar new energy power station is characterized by comprising the following components: