CN111313466A - A method and system for optimal regulation of AGC of sending-end power grid based on wind priority regulation - Google Patents

Abstract

The invention discloses a sending end power grid AGC optimization regulation and control method and a system based on wind power priority regulation, wherein the method comprises the following steps: s1: calculating and solving an ACE value according to a real-time frequency value of a power grid monitored in real time and the exchange power of a tie line; s2: calculating an adjustable power interval of the wind power plant according to the ultra-short-term power predicted value and the actual power of the grid-connected operation wind power plant; s3: selecting the wind power plants participating in AGC regulation according to the size of the adjustable power interval of the wind power plants and the size of the ACE value, and sequencing; s4: and determining the units participating in adjustment according to the ACE value, and cooperatively allocating the thermal power unit and the wind power plant to jointly complete AGC rapid adjustment. The method shortens the frequency stabilization time of the power grid by utilizing the rapidity of the power regulation of the wind power plant, ensures the ACE performance index of the power grid, and ensures the safe and stable operation of the power grid.

Description

A method and system for optimal regulation of AGC of sending-end power grid based on wind priority regulation

technical field

The invention relates to a method and a system for optimizing and regulating AGC of a sending-end power grid based on wind priority regulation, and belongs to the technical field of grid-source coordination control.

Background technique

In recent years, my country's wind power has developed rapidly, and the wind power industry has developed rapidly. However, wind energy has the characteristics of intermittency, volatility and uncertainty. Conventional power frequency control is difficult to meet the system stability requirements. At the same time, the increase in the scale of wind power has squeezed the proportion of traditional frequency regulation units. The traditional frequency regulation units cannot meet the increasing power quality requirements of high wind power penetration power grids in terms of the quality and flexibility of frequency regulation. Participate in FM. In order to eliminate the negative impact of wind power on the frequency stability of the system, some recently released power grid guidelines at home and abroad clearly stated that grid-connected wind farms need to provide the same auxiliary functions as rotating backup, inertial response and frequency regulation as conventional power plants. Among them, the national standard GB/T 19963-2011 "Technical Regulations for Wind Farm Access to Power System" promulgated by my country clearly states that grid-connected wind farms should have the ability to participate in frequency regulation, peak regulation and backup of the power system.

The power grid frequency must be controlled within an allowable range around 50Hz during operation of the power system, that is, the premise of stable operation of the power system is the real-time balance of power generation and power consumption, otherwise it will cause the power quality of the system to decline, and even lead to system instability in extreme cases. . Automatic generation control (AGC) is an automatic integrated control system that realizes the real-time balance of power generation and load in the power system and ensures that the grid frequency and tie line exchange power are maintained at specified values. For the safe and stable operation of the power grid, as the main force of frequency regulation and peak regulation of the current power grid, large thermal power units are required to be put into automatic generation control (AGC) function.

The power grid AGC performance is called in each AGC data collection cycle to evaluate the control behavior of the AGC, and the evaluation standard is mainly the NERC (National Electrical Research Council, North American Electric Power System Reliability Association) code of conduct. The power grid AGC performance can calculate and count the performance indicators of the operating area, the performance indicators of the unit, and can also calculate the frequency, exchange power, ACE (Area Control Error, area control deviation) under different threshold values and different conditions (such as whether AGC is used, etc.) lower pass rate. Figure 1 shows a schematic diagram of grid-source AGC coordinated deployment control, in which ACE is calculated according to grid frequency and tie line power flow. After ACE is generated, it is assigned to each AGC unit to act together according to a certain mechanism to eliminate deviation and achieve grid frequency stability. As early as 1973, NERC formally adopted the A1 and A2 standards to evaluate the control performance of the power grid under normal conditions. The contents are: A1 standard: the ACE in the control area must cross zero at least once within 10 minutes; A2 standard: the ACE in the control area The average value within 10min must be controlled within the specified range _La . NERC requires that the control pass rate of each control area to reach A1 and A2 standards is more than 90%. In this way, by implementing the A1 and A2 standards, the ACE of each control area is always close to zero, thereby ensuring the balance between the electricity load and power generation, planned exchange and actual exchange. NERC launched the CPS1 and CPS2 control performance evaluation standards in 1996, which were officially implemented in 1998, replacing the original A1 and A2 standards. Similar to the A1 and A2 standards, it is required that the average value of ACE every 10min must be controlled within the specified range _La . At present, the domestic AGC control performance evaluation mainly adopts two sets of standards implemented by NERC: A1 and A2 standards and CPS1 and CPS2 standards. CPS2 standard.

The domestic power grids in North China, Northwest China, Northeast China and other regions have formulated corresponding standards and real-time detailed rules in accordance with the country's "two detailed rules". The thermal power unit of the steam drum furnace is 1.5% of the rated active power of the unit; the general thermal power unit with an intermediate storage silo type pulverizing system is 2% of the rated active power of the unit. The value of active power regulation rate A1 in Figure 2 is generally set to 1%-2% P _n MW/min (P _n is the rated power of the unit), and the unit increases or decreases the active power at the same rate. Domestic thermal power units are mainly 300MW and 600MW units, and most thermal power units have a regulation rate of 4.5-10MW/min. According to GB/T 19963-2011, the 1min active power change limit of wind farms under normal operation is: 3MW for wind farms less than 30MW, installed capacity/10 for wind farms of 30-150MW, and wind farms greater than 150MW is 15MW. At present, the capacity of domestic wind farms generally exceeds 49.5MW, and the proportion of 300MW scale is increasing rapidly, that is to say, the active power change rate of most wind farms is 4.95-15MW/min, that is, within the adjustable range, the wind power The regulation rate is better than that of conventional thermal power units.

At present, the domestic units used for AGC regulation are generally thermal power units, and the wind farms operate in the maximum power tracking control mode. The increase of wind power generation and the decrease of thermal power generation can easily lead to insufficient power adjustment and change ability of the power grid in a certain period of time in the day, and it cannot ensure that the average value of the control deviation of the grid region within a certain period of time is controlled within the specified range. , if the ACE is too large, a large number of operating units need to be removed from the sending end grid, and a certain amount of load should be removed from the sending end grid, otherwise a chain reaction will occur, resulting in system instability. At the same time, the fluctuation of wind power will also cause traditional thermal power units to frequently act in response to changes in grid frequency, causing wear and tear of mechanical components, reducing the operating life of frequency-modulating units, and affecting grid security and power quality.

SUMMARY OF THE INVENTION

In order to solve the above problems, the present invention proposes a method and system for optimizing the AGC control of the sending-end power grid based on wind priority adjustment, which can preferentially utilize the wind farm for rapid power adjustment and ensure the stable operation of the power grid.

The technical scheme adopted by the present invention to solve its technical problems is:

On the one hand, a method for optimizing and regulating AGC of a sending-end power grid based on wind priority regulation provided by an embodiment of the present invention includes the following steps:

S1: Calculate the ACE value according to the real-time frequency value of the power grid monitored in real time and the exchange power of the tie line;

S2: Calculate the adjustable power range of the wind farm according to the ultra-short-term power forecast value and actual power of the grid-connected wind farm;

S3: Select the wind farms participating in the AGC adjustment according to the size of the adjustable power range of the wind farm and the size of the ACE value, and sort them;

S4: Determine the units participating in the adjustment according to the size of the ACE value, and coordinate the deployment of thermal power units and wind farms to complete the rapid AGC adjustment.

As a possible implementation manner of this embodiment, in step S1, the calculation formula of the ACE value is:

ACE=BΔf+ _ΔPtie

Among them, B is the frequency deviation coefficient of the area, Δf is the frequency deviation between the measured frequency f of the power grid and the rated frequency 50Hz, that is, Δf=ff ₀ =f-50; ΔP _tie is the actual value of the tie line exchange power P _tiea minus the planned Deviation value obtained from the value P _ties

As a possible implementation manner of this embodiment, in step S2, the ultra-short-term power prediction value P _P of the grid-connected wind farm is the 15min-4h wind farm generation power prediction value reported by the wind farm, which at least satisfies NB/T 31046-2013 "Functional Specification for Wind Power Prediction System" and Q/GDW 10588-2015 "Functional Specification for Wind Power Prediction".

As a possible implementation manner of this embodiment, in step S2, the calculation process of the adjustable power interval of the wind farm:

During normal operation, the wind power is in the maximum power tracking control mode, and the upper limit P _H of the wind farm output is selected from the larger value of the ultra-short-term power prediction value P _P and the actual power P _A of the wind farm;

The lower limit P _L of the wind farm output is selected as 20% P _n , and P _n is the rated power of the wind turbine;

In the adjustable power range of the wind farm, the lower power range is [P _L , P _A ], and the upward power range is [P _A , P _H ].

As a possible implementation manner of this embodiment, in step S3, the downward adjustment amplitude of the wind farm is P _D =P _A -PL , and the _upward adjustment amplitude of the wind farm is P _I =P _H -P _A .

As a possible implementation manner of this embodiment, in step S3, when the ACE is a positive value, the AGC power needs to be lowered, and the order is based on P _D from large to small; when the ACE is a negative value, the AGC power needs to be raised, according to P _I sort from largest to smallest.

As _a possible implementation manner of this embodiment, in step S3, the actual power PA of the wind farm is less than 20% P _n , and the wind farm participating in the _AGC adjustment does not perform AGC power reduction; the actual power PA of the wind farm is greater than the upper limit of the output of the wind farm At _PH , the wind farms participating in the AGC regulation do not perform AGC power upward regulation.

As a possible implementation manner of this embodiment, the process of step S4 includes the following steps:

When |ACE|≤L _d , no AGC adjustment is required, and the AGC command remains unchanged;

则按照P_D排序选取前n座风电场共同通过AGC调节消除ACE；如果

则由并网运行的风电场与火电机组共同完成AGC调节，风电场完成

火电机组完成

部分；When ACE>L _d , if

Then select the top n wind farms according to _PD order to eliminate ACE through AGC adjustment; if

AGC adjustment is completed by the grid-connected wind farm and the thermal power unit, and the wind farm is completed.

Thermal power unit completed

part;

则按照P_I排序选取前n座风电场共同通过AGC调节消除ACE；如果

则由并网运行的风电场与火电机组共同完成AGC调节，风电场完成

火电机组完成

部分；When ACE <-L _d , if

Then select the top n wind farms in the order of _PI to eliminate ACE through AGC adjustment; if

AGC adjustment is completed by the grid-connected wind farm and the thermal power unit, and the wind farm is completed.

Thermal power unit completed

part;

Among them, P _Di is the wind farm downward adjustment amplitude of the ith wind farm, P _Ii is the wind farm upward adjustment amplitude of the ith wind farm, and L _d is the ACE dead zone value in the control area that does not need to be adjusted.

On the other hand, an AGC optimization control system for a sending-end power grid based on wind priority adjustment provided by an embodiment of the present invention includes:

The ACE value calculation module is used to calculate and calculate the ACE value according to the real-time frequency value of the power grid monitored in real time and the exchange power of the tie line;

The adjustable power interval calculation module is used to calculate the adjustable power interval of the wind farm according to the ultra-short-term power forecast value and actual power of the grid-connected wind farm;

The sorting module is used to select and sort the wind farms participating in the AGC adjustment according to the size of the adjustable power interval of the wind farm and the size of the ACE value;

The adjustment unit determination module is used to determine the units participating in the adjustment according to the value determined by the ACE, and coordinately deploy the thermal power unit and the wind farm to complete the AGC rapid adjustment.

As a possible implementation manner of this embodiment, the sending-end power grid AGC optimization control system based on wind priority adjustment further includes:

The power grid monitoring module is used to calculate and obtain the ACE value according to the real-time frequency value of the power grid monitored in real time and the exchange power of the tie line;

The wind farm monitoring module is used to calculate the adjustable power range of the wind farm according to the ultra-short-term power forecast value and actual power of the grid-connected wind farm.

The beneficial effects that the technical solutions of the embodiments of the present invention can have are as follows:

The technical scheme of the embodiment of the present invention firstly calculates and obtains the ACE value according to the real-time frequency value of the power grid monitored in real time and the exchange power of the tie line; Then select the wind farms participating in the AGC adjustment according to the size of the adjustable power interval of the wind farm and the size of the ACE value, and sort them; finally, determine the units participating in the adjustment according to the size of the ACE value, and coordinate the deployment of thermal power units and wind farms to complete the AGC fast adjust. According to the change range of ACE in the regional power grid, the invention preferentially utilizes the wind farm for fast power adjustment and coordinates the deployment of the thermal power unit and the wind farm to jointly complete the AGC adjustment, and utilizes the rapidity of the power adjustment of the wind farm to shorten the frequency stabilization time of the power grid and ensure the ACE performance of the power grid. The index effectively reduces the operation frequency of traditional thermal power units due to the fluctuation of wind power, reduces the wear and tear of mechanical components of thermal power units, improves the operating life of frequency-modulated thermal power units, and ensures the safe and stable operation of the power grid.

Compared with the prior art, the present invention has the following characteristics:

(1) According to the variation range of ACE in the regional power grid, the present invention utilizes the rapidity of power regulation of the wind farm to shorten the grid frequency stabilization time, to ensure that the average value of the regional control deviation of the power grid is controlled within a specified range within a certain period of time, and to ensure that the power transmission Safe and stable operation of the end grid.

(2) The present invention dynamically allocates wind turbines to participate in grid AGC regulation, reduces the operating frequency of traditional thermal power units due to wind power fluctuations, reduces the wear and tear of mechanical components of thermal power units, and increases the operating life of frequency-modulated thermal power units.

Description of drawings:

1 is a schematic diagram of a network source AGC coordinated deployment control;

Fig. 2 is a kind of schematic diagram of conventional thermal power unit AGC control;

3 is a flow chart of a method for optimizing and regulating AGC of a sending-end power grid based on wind priority regulation according to an exemplary embodiment;

Fig. 4 is a structural diagram of an AGC optimal regulation system of a sending-end power grid based on wind priority regulation according to an exemplary embodiment.

Detailed ways

Below in conjunction with accompanying drawing and embodiment, the present invention will be further described:

In order to clearly illustrate the technical features of the solution, the present invention will be described in detail below through specific embodiments and in conjunction with the accompanying drawings. The following disclosure provides many different embodiments or examples for implementing different structures of the invention. In order to simplify the disclosure of the present invention, the components and arrangements of specific examples are described below. Furthermore, the present invention may repeat reference numerals and/or letters in different instances. This repetition is for the purpose of simplicity and clarity and does not in itself indicate a relationship between the various embodiments and/or arrangements discussed. It should be noted that the components illustrated in the figures are not necessarily drawn to scale. Descriptions of well-known components and processing techniques and processes are omitted from the present invention to avoid unnecessarily limiting the present invention.

Fig. 3 is a flow chart of a method for optimizing and regulating AGC of a sending-end power grid based on wind priority regulation according to an exemplary embodiment. As shown in FIG. 3 , a method for optimizing and regulating AGC of a sending-end power grid based on wind priority regulation provided by an embodiment of the present invention includes the following steps:

S1: Calculate the ACE value according to the real-time frequency value of the power grid monitored in real time and the exchange power of the tie line;

S2: Calculate the adjustable power range of the wind farm according to the ultra-short-term power forecast value and actual power of the grid-connected wind farm;

S3: Select the wind farms participating in the AGC adjustment according to the size of the adjustable power range of the wind farm and the size of the ACE value, and sort them;

S4: Determine the units participating in the adjustment according to the size of the ACE value, and coordinate the deployment of thermal power units and wind farms to complete the rapid AGC adjustment.

As a possible implementation manner of this embodiment, in step S1, the calculation formula of the ACE value is:

ACE=BΔf+ _ΔPtie

电网实时频率值和联络线交换功率可由现有相关电网监测设备进行实时监测获取。Among them, B is the frequency deviation coefficient of the area, Δf is the frequency deviation between the measured frequency f of the power grid and the rated frequency 50Hz, that is, Δf=ff ₀ =f-50; ΔP _tie is the actual value of the tie line exchange power P _tiea minus the planned Deviation value obtained from the value P _ties

The real-time frequency value of the power grid and the exchange power of the tie line can be obtained by real-time monitoring with the existing related power grid monitoring equipment.

As a possible implementation manner of this embodiment, in step S2, the ultra-short-term power prediction value P _P of the grid-connected wind farm is the 15min-4h wind farm generating power prediction value reported by the wind farm, which at least needs to satisfy NB/ T 31046-2013 "Functional Specification for Wind Power Prediction System" and Q/GDW 10588-2015 "Functional Specification for Wind Power Prediction" and other relevant standards. The ultra-short-term power prediction value and actual power of the grid-connected wind farm can be collected by the existing grid-connected wind farm monitoring equipment to collect the ultra-short-term power prediction value of the grid-connected wind farm, and monitor the actual power of the grid-connected wind farm.

As a possible implementation manner of this embodiment, in step S2, the calculation process of the adjustable power interval of the wind farm:

During normal operation, the wind power is in the maximum power tracking control mode, and the upper limit P _H of the wind farm output is selected from the larger value of the ultra-short-term power prediction value P _P and the actual power P _A of the wind farm;

According to the regulations of GB/T 19963-2011, the lower limit of continuous and smooth adjustment of active power is 20% of the rated power P _n of the wind turbine, so the lower limit P _L of the wind farm output is selected as 20% P _n , and P _n is the rated power of the wind turbine;

In the adjustable power range of the wind farm, the lower power range is [P _L , P _A ], and the upward power range is [P _A , P _H ].

As a possible implementation manner of this embodiment, in step S3, the downward adjustment amplitude of the wind farm is P _D =P _A -PL , and the _upward adjustment amplitude of the wind farm is P _I =P _H -P _A .

As a possible implementation manner of this embodiment, in step S3, when the ACE is a positive value, the AGC power needs to be lowered, and the order is based on P _D from large to small; when the ACE is a negative value, the AGC power needs to be raised, according to P _I sort from largest to smallest.

As _a possible implementation manner of this embodiment, in step S3, the actual power PA of the wind farm is less than 20% P _n , and the wind farm participating in the _AGC adjustment does not perform AGC power reduction; the actual power PA of the wind farm is greater than the upper limit of the output of the wind farm At _PH , the wind farms participating in the AGC regulation do not perform AGC power upward regulation.

As a possible implementation manner of this embodiment, the process of step S4 includes the following steps:

When |ACE|≤L _d , no AGC adjustment is required, and the AGC command remains unchanged;

则按照P_D排序选取前n座风电场共同通过AGC调节消除ACE；如果

则由并网运行的风电场与火电机组共同完成AGC调节，风电场完成

火电机组完成

部分；When ACE>L _d , if

Then select the top n wind farms according to _PD order to eliminate ACE through AGC adjustment; if

AGC adjustment is completed by the grid-connected wind farm and the thermal power unit, and the wind farm is completed.

Thermal power unit completed

part;

则按照P_I排序选取前n座风电场共同通过AGC调节消除ACE；如果

则由并网运行的风电场与火电机组共同完成AGC调节，风电场完成

火电机组完成

部分；When ACE <-L _d , if

Then select the top n wind farms in the order of _PI to eliminate ACE through AGC adjustment; if

AGC adjustment is completed by the grid-connected wind farm and the thermal power unit, and the wind farm is completed.

Thermal power unit completed

part;

Among them, P _Di is the wind farm downward adjustment amplitude of the ith wind farm, P _Ii is the wind farm upward adjustment amplitude of the ith wind farm, L _d is the ACE dead zone value in the control area that does not need to be adjusted, and the value of L _d The range is generally 70-120MW.

In this embodiment, according to the variation range of ACE in the regional power grid, the wind farm is preferentially used for fast power adjustment, and the thermal power unit and the wind farm are jointly deployed to complete the AGC adjustment. The rapidity of the power adjustment of the wind farm is used to shorten the frequency stabilization time of the power grid and ensure the ACE of the power grid. The performance indicators effectively reduce the operation frequency of traditional thermal power units due to the fluctuation of wind power, reduce the wear and tear of mechanical components of thermal power units, improve the operating life of frequency-modulated thermal power units, and ensure the safe and stable operation of the power grid.

Fig. 4 is a structural diagram of an AGC optimal regulation system of a sending-end power grid based on wind priority regulation according to an exemplary embodiment. As shown in FIG. 4 , an AGC optimization control system for a sending-end power grid based on wind priority adjustment provided by an embodiment of the present invention includes:

The ACE value calculation module is used to calculate and calculate the ACE value according to the real-time frequency value of the power grid monitored in real time and the exchange power of the tie line;

The adjustable power interval calculation module is used to calculate the adjustable power interval of the wind farm according to the ultra-short-term power forecast value and actual power of the grid-connected wind farm;

The sorting module is used to select and sort the wind farms participating in the AGC adjustment according to the size of the adjustable power interval of the wind farm and the size of the ACE value;

The adjustment unit determination module is used to determine the units participating in the adjustment according to the value determined by the ACE, and coordinately deploy the thermal power unit and the wind farm to complete the AGC rapid adjustment.

As a possible implementation manner of this embodiment, the sending-end power grid AGC optimization control system based on wind priority adjustment further includes:

The power grid monitoring module is used to calculate and obtain the ACE value according to the real-time frequency value of the power grid monitored in real time and the exchange power of the tie line;

The wind farm monitoring module is used to calculate the adjustable power range of the wind farm according to the ultra-short-term power forecast value and actual power of the grid-connected wind farm.

The following takes a regional power grid as an example to give an application example of the method proposed by the present invention in an actual power grid.

The thermal power in the provincial power grid is dominated by 300MW positive pressure direct-blowing units, and the power regulation rate of the units stipulated in the "Implementation Rules for the Grid-connected Operation Management of Power Plants in North China": the steam drum furnace of the general direct-blowing pulverizing system The thermal power unit is 1.5% of the rated active power of the unit, and the general thermal power unit with an intermediate storage silo type pulverizing system is 2% of the rated active power of the unit. According to regulations, the power regulation rate of 300MW direct-blowing units is 4.5MW/min respectively. The dead zone value of the grid ACE dynamic adjustment is 70, and the ACE value is in [-70,70], that is, when -70≤ACE≤70, the AGC adjustment of the units in the grid is not performed.

As of October 2019, the provincial power grid has 95 wind farms with a total capacity of 9,554MW. Wind power output is quite random. Taking October 2019 as an example, the maximum output in that month was 6885MW and the minimum output was 117MW. According to GB/T 19963-2011, the limit of 1min active power change of wind farms under normal operation is: 3MW for wind farms less than 30MW, installed capacity/10 for wind farms of 30-150MW, and 15MW for wind farms greater than 150MW . There are 91 wind farms with a capacity of more than 49.5MW and 37 wind farms with a capacity of more than 100MW in the provincial power grid. That is to say, the active power change rate of most wind farms exceeds 4.95MW/min, and more than 38% of the wind farms have a change in active power. When the rate exceeds 10MW/min, that is, within the adjustable range, the adjustment rate of the wind farm is better than that of conventional thermal power units.

At a certain time in October, affected by the fault of the external DC line, the frequency value of the power grid rose to 50.09Hz, and the ACE value was 236MW after calculation and filtering, which exceeded the dead zone value. At this time, there are 78 wind farms connected to the grid and in operation, of which 9 are monitored with the actual power of wind turbines exceeding 20% of their rated power. The specific data are shown in Table 1.

Table 1 Relevant data of 9 wind farms operating above 20% P _n

Further, to obtain the adjustable power range of the wind farm, the upper limit P _H of the wind farm output can be selected from the larger value of the ultra-short-term power prediction value P _P and the actual power P _A of the wind farm; according to GB/T 19963-2011, the active power _The lower limit of continuous smooth adjustment is 20% of the rated power P _n of the wind _turbine , and the lower limit P _L of the wind _farm output is 20% P _{n ;} ], the downward adjustment amplitude of the wind farm is P _D =P _A -PL , and the upward adjustment amplitude of the wind farm is P _I =P _H -P _{A .} Since the grid frequency is 50.09Hz, the ACE value is 236MW after calculation and filtering. , the power grid needs to reduce the AGC power, and sort according to _PD from large to small. The specific data are shown in Table 2.

Table 2 Statistical table of downward adjustment intervals for 9 wind farms operating above 20% P _n

小于236MW的ACE，即触发

则由并网运行的风电场与火电机组共同完成AGC调节，风电场完成

的AGC功率下调，火电机组完成

的AGC功率下调部分。也就是说此时同时给具备下调能力的9座风电场和参与AGC调节的火电机组下发AGC功率下调指令，迅速消除ACE偏差。实际运行结果证明，与常规仅依靠火电机组调节相比，调节时间缩短超过20％，提升了电网安全稳定水平。Because at this time

ACE less than 236MW, i.e. trigger

AGC adjustment is completed by the grid-connected wind farm and the thermal power unit, and the wind farm is completed.

The AGC power is lowered, the thermal power unit is completed

the AGC power down section. That is to say, at this time, AGC power down-regulation commands are issued to 9 wind farms with down-regulation capability and thermal power units participating in AGC regulation at the same time, so as to quickly eliminate the ACE deviation. The actual operation results have proved that compared with the conventional regulation only relying on thermal power units, the regulation time is shortened by more than 20%, which improves the safety and stability of the power grid.

Compared with the prior art, the present invention has the following characteristics:

(1) According to the variation range of ACE in the regional power grid, the present invention utilizes the rapidity of power regulation of the wind farm to shorten the grid frequency stabilization time, to ensure that the average value of the regional control deviation of the power grid is controlled within a specified range within a certain period of time, and to ensure that the power transmission Safe and stable operation of the end grid.

(2) The present invention dynamically allocates wind turbines to participate in grid AGC regulation, reduces the operating frequency of traditional thermal power units due to wind power fluctuations, reduces the wear and tear of mechanical components of thermal power units, and increases the operating life of frequency-modulated thermal power units.

The above are only the preferred embodiments of the present invention. For those skilled in the art, without departing from the principles of the present invention, several improvements and modifications can be made, and these improvements and modifications are also regarded as the present invention. the scope of protection of the invention.

Claims (10)

1. a kind of optimal control method for sending end power grid AGC based on wind priority regulation, is characterized in that, comprises the following steps: S1: Calculate the ACE value according to the real-time frequency value of the power grid monitored in real time and the exchange power of the tie line; S2: Calculate the adjustable power range of the wind farm according to the ultra-short-term power forecast value and actual power of the grid-connected wind farm; S3: Select the wind farms participating in the AGC adjustment according to the size of the adjustable power range of the wind farm and the size of the ACE value, and sort them; S4: Determine the units participating in the adjustment according to the size of the ACE value, and coordinate the deployment of thermal power units and wind farms to complete the rapid AGC adjustment. 2. a kind of sending-end power grid AGC optimization control method based on wind priority adjustment according to claim 1, is characterized in that, in step S1, the calculation formula of described ACE value is: ACE=BΔf+ _ΔPtie Among them, B is the frequency deviation coefficient of the area, Δf is the frequency deviation between the measured frequency f of the power grid and the rated frequency 50Hz, that is, Δf=ff ₀ =f-50; ΔP _tie is the actual value of the tie line exchange power P _tiea minus the planned Deviation value ΔP _tie =P _tiea −P _ties obtained from the value P _ties . 3. A kind of sending-end power grid AGC optimization control method based on wind priority adjustment according to claim 1 or 2, is characterized in that, in step S2, described grid-connected operation wind farm ultra-short-term power prediction value _PP is The 15min-4h wind power forecast value reported by the wind farm meets the requirements of NB/T 31046-2013 "Functional Specification for Wind Power Prediction System" and Q/GDW10588-2015 "Functional Specification for Wind Power Prediction". 4. a kind of sending-end power grid AGC optimization control method based on wind priority adjustment according to claim 3, is characterized in that, in step S2, the calculation process of described wind farm adjustable power interval: During normal operation, the wind power is in the maximum power tracking control mode, and the upper limit P _H of the wind farm output is selected from the larger value of the ultra-short-term power prediction value P _P and the actual power P _A of the wind farm; The lower limit P _L of the wind farm output is selected as 20% P _n , and P _n is the rated power of the wind turbine; In the adjustable power range of the wind farm, the lower power range is [P _L , P _A ], and the upward power range is [P _A , P _H ]. 5 . The AGC optimization control method for the sending-end power grid based on wind priority adjustment according to claim 4 , wherein, in step S3, the wind farm down-adjustment amplitude is P _{D =} P _A -PL , and the wind farm up-adjustment. 6 . The amplitude is P _I = P _H - P _A . 6. A kind of sending-end power grid AGC optimization control method based on wind priority adjustment according to claim 5, is characterized in that, in step S3, when ACE is a positive value, AGC power needs to be lowered, according to _PD from large to large Sort by small value; when ACE is negative, the AGC power needs to be increased, and sorted according to _PI from large to small. 7 . The AGC optimization control method of the sending _- end power grid based on wind priority adjustment according to claim 5 , wherein in step S3, the actual power PA of the wind farm is less than 20% P _n , and the wind farm participating in the AGC adjustment No AGC power reduction is performed; when the actual power PA of the wind farm is greater than the wind farm output upper limit _PH , the wind _farms participating in the AGC adjustment do not perform AGC power upward adjustment. 8. A kind of wind power priority regulation based on wind power priority regulation AGC optimal regulation method for sending-end power grid according to claim 6, is characterized in that, the process of described step S4 comprises the following steps: When |ACE|≤L _d , no AGC adjustment is required, and the AGC command remains unchanged; When ACE>L _d , if

Then select the top n wind farms according to _PD order to eliminate ACE through AGC adjustment; if

AGC adjustment is completed by the grid-connected wind farm and the thermal power unit, and the wind farm is completed.

Thermal power unit completed

part; When ACE <-L _d , if

Then select the top n wind farms in the order of _PI to eliminate ACE through AGC adjustment; if

AGC adjustment is completed by the grid-connected wind farm and the thermal power unit, and the wind farm is completed.

Thermal power unit completed

part; Among them, P _Di is the wind farm downward adjustment amplitude of the ith wind farm, P _Ii is the wind farm upward adjustment amplitude of the ith wind farm, and L _d is the ACE dead zone value in the control area that does not need to be adjusted. 9. A sending-end power grid AGC optimization control system based on wind priority adjustment, is characterized in that, comprises: The ACE value calculation module is used to calculate and calculate the ACE value according to the real-time frequency value of the power grid monitored in real time and the exchange power of the tie line; The adjustable power interval calculation module is used to calculate the adjustable power interval of the wind farm according to the ultra-short-term power forecast value and actual power of the grid-connected wind farm; The sorting module is used to select and sort the wind farms participating in the AGC adjustment according to the size of the adjustable power interval of the wind farm and the size of the ACE value; The adjustment unit determination module is used to determine the units participating in the adjustment according to the value determined by the ACE, and coordinately deploy the thermal power unit and the wind farm to complete the AGC rapid adjustment. 10. The transmission-end power grid AGC optimization control system based on wind priority adjustment according to claim 9, characterized in that, further comprising: The power grid monitoring module is used to calculate and obtain the ACE value according to the real-time frequency value of the power grid monitored in real time and the exchange power of the tie line; The wind farm monitoring module is used to calculate the adjustable power range of the wind farm according to the ultra-short-term power forecast value and actual power of the grid-connected wind farm.

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