CN110350554B - Wind storage system auxiliary power grid primary frequency modulation control method based on series-parallel structure - Google Patents
Wind storage system auxiliary power grid primary frequency modulation control method based on series-parallel structure Download PDFInfo
- Publication number
- CN110350554B CN110350554B CN201910634025.XA CN201910634025A CN110350554B CN 110350554 B CN110350554 B CN 110350554B CN 201910634025 A CN201910634025 A CN 201910634025A CN 110350554 B CN110350554 B CN 110350554B
- Authority
- CN
- China
- Prior art keywords
- frequency modulation
- storage system
- wind
- energy storage
- output
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 238000000034 method Methods 0.000 title claims abstract description 35
- 238000004146 energy storage Methods 0.000 claims abstract description 128
- 238000011217 control strategy Methods 0.000 claims abstract description 69
- 230000009471 action Effects 0.000 claims abstract description 12
- 238000005457 optimization Methods 0.000 claims abstract description 11
- 238000004422 calculation algorithm Methods 0.000 claims abstract description 6
- 230000002068 genetic effect Effects 0.000 claims abstract description 6
- 230000004044 response Effects 0.000 claims description 31
- 238000012546 transfer Methods 0.000 claims description 13
- 238000004364 calculation method Methods 0.000 claims description 5
- 238000010276 construction Methods 0.000 claims description 3
- 230000005611 electricity Effects 0.000 claims description 3
- 238000012423 maintenance Methods 0.000 claims description 3
- 230000000694 effects Effects 0.000 abstract description 8
- 230000002035 prolonged effect Effects 0.000 abstract description 4
- 230000008569 process Effects 0.000 description 10
- 238000004088 simulation Methods 0.000 description 10
- 230000008859 change Effects 0.000 description 4
- 238000005094 computer simulation Methods 0.000 description 1
- 230000003111 delayed effect Effects 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 230000035699 permeability Effects 0.000 description 1
- 238000010248 power generation Methods 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 238000005070 sampling Methods 0.000 description 1
- 230000001360 synchronised effect Effects 0.000 description 1
- 238000012795 verification Methods 0.000 description 1
Images
Classifications
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/24—Arrangements for preventing or reducing oscillations of power in networks
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/28—Arrangements for balancing of the load in a network by storage of energy
-
- H02J3/386—
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/38—Arrangements for parallely feeding a single network by two or more generators, converters or transformers
- H02J3/46—Controlling of the sharing of output between the generators, converters, or transformers
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J2203/00—Indexing scheme relating to details of circuit arrangements for AC mains or AC distribution networks
- H02J2203/20—Simulating, e g planning, reliability check, modelling or computer assisted design [CAD]
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E10/00—Energy generation through renewable energy sources
- Y02E10/70—Wind energy
- Y02E10/76—Power conversion electric or electronic aspects
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E70/00—Other energy conversion or management systems reducing GHG emissions
- Y02E70/30—Systems combining energy storage with energy generation of non-fossil origin
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Supply And Distribution Of Alternating Current (AREA)
- Control Of Eletrric Generators (AREA)
Abstract
The invention discloses a primary frequency modulation control method of an auxiliary power grid of a wind storage system based on a series-parallel structure, which comprises the following steps of (1) collecting the actual frequency of a power system, and calculating the frequency deviation of the current system; (2) establishing a wind storage system model, and calculating serial frequency modulation task components and the switching time of the system; (3) according to the frequency deviation of the system, the output of the current wind turbine generator and the output of the energy storage system are respectively calculated, the task is sent to the wind turbine generator and the energy storage system to carry out primary frequency modulation, and after the time reaches the switching time, the control mainly takes the mode of series frequency modulation as the main mode and the mode of parallel frequency modulation as the main mode. The serial frequency modulation task component is obtained by modeling the system and optimizing by utilizing a genetic algorithm. The invention can basically achieve the required output of system frequency modulation within 0.3s, thereby ensuring the frequency modulation effect; the energy storage action amount can be reduced through the optimization control strategy, the energy storage service time is prolonged, and the frequency modulation economy is improved.
Description
Technical Field
The invention relates to a power system frequency modulation control method, in particular to a wind storage system auxiliary power grid primary frequency modulation control method based on a series-parallel structure.
Background
By the end of 2017, the wind power total installation reaches 1.88 hundred million kilowatts in China, and China becomes a large country for wind energy utilization. The wind power generation unit self-participating frequency modulation control method mainly aims at sacrificing economy or reducing load capacity, and meanwhile, the one-time frequency modulation rapidity requirement of the power system is difficult to meet in the aspect of response speed, the energy storage system has the characteristics of high power density, high response speed and the like, and a new mode is provided for the one-time frequency modulation of the power system.
At present, wind storage frequency modulation is mainly researched by analyzing the wind power frequency modulation capacity improvement and how to output energy storage and wind power under a frequency modulation instruction, and the problem of how to distribute energy storage systems and wind power after the frequency modulation instruction is issued is not considered, so that the problem of being worthy of exploration is to design a wind storage system frequency modulation control strategy according to energy distribution before the energy storage systems and the wind power.
Disclosure of Invention
The purpose of the invention is as follows: aiming at the problems, the invention provides a primary frequency modulation control method of an auxiliary power grid of a wind storage system based on a series-parallel structure, which realizes that the required output of system frequency modulation is achieved in a very short time in the starting stage of a traditional frequency modulation standby unit, reduces the energy storage action amount after the starting of the traditional unit is finished, and prolongs the energy storage service time.
The technical scheme is as follows: the invention adopts the technical scheme that a wind storage system auxiliary power grid primary frequency modulation control method based on a series-parallel structure comprises the following steps:
(1) acquiring the actual frequency of a power system in a wind storage system with a series-parallel mixed structure, and calculating the frequency deviation of the current system;
(2) establishing a wind storage system model, calculating a serial frequency modulation task component K and the switching time t of the system0；
Wherein the serial FM task component K and the switching time t0The calculation method of (2) is as follows:
(21) modeling a wind turbine generator and an energy storage system in the system, and respectively establishing serial and parallel models of the wind turbine generator and the energy storage system;
the virtual frequency response transfer function of the wind turbine generator is as follows:
wherein k isvdIs the virtual inertial response coefficient; k is a radical ofchangeIs the primary frequency modulation coefficient; t iswind1Is the virtual inertial response time constant; t iswind2Is the pitch time constant; s represents the laplacian operator; gwRepresenting a wind turbine generator virtual frequency response transfer function;
the energy storage system transfer function is:
wherein k isvdIs the virtual inertial response coefficient; k is a radical ofchangeIs the primary frequency modulation coefficient; t isEnergvAn energy storage output response time constant; s represents the laplacian operator.
(22) Establishing an optimal control objective function of the wind storage system;
the wind storage system optimization control objective function is as follows:
min[C1·Δfdev+C2·Δfsta+C3·S]
wherein, C1As a frequency nadir penalty factor, C2Penalty factors for steady-state frequency values, C3For frequency energy storage action penalty factor, Δ fdevIs the lowest point of frequency,. DELTA.fstaAnd S is the cost of the energy storage system in the primary frequency modulation process.
(23) Searching the optimal solution of the optimal control objective function of the wind storage system by adopting a genetic algorithm to obtain the optimal serial frequency modulation task component K and the optimal switching time t0。
Preferably, the penalty factor for the lowest frequency point is 0.25, the penalty factor for the steady-state frequency value is 0.25, and the penalty factor for the frequency energy storage action amount is 0.5.
(24) Simulating the system, traversing time variable, and switching time t0Corresponding to the time value when the frequency deviation is maximum and the steady state frequency value is minimum.
(3) Based on serial frequency modulation control, according to the frequency of the systemCalculating the output of the wind turbine generator and the energy storage system according to the serial frequency modulation task component K obtained in the step (2), and sending the task to the wind turbine generator and the energy storage system for primary frequency modulation; reaches the switching time t0And then, switching to the mode that parallel frequency modulation control is mainly used, namely the serial frequency modulation task component is 1-K, the parallel frequency modulation task component is K, respectively calculating the output of the wind turbine generator and the energy storage system, and transmitting the task to the wind turbine generator and the energy storage system for primary frequency modulation. Wherein the calculated output is 0 < t0Time period and t0T < T period of time,
at 0 < t0Outputting power by the wind storage combined system in a time interval;
is at t0The wind storage combined system outputs power in a time period of T; t is primary frequency modulation maintaining time;
wherein
At 0 < t0The time interval output is as follows:
in the formula: delta Pchu1At 0 < t0In time period, optimizing the serial output condition of the wind storage combined system under the control strategy; delta Pbin1At 0 < t0In time period, optimizing the parallel output condition of the wind storage combined system under the control strategy; delta Pwchu1At 0 < t0In time interval, the output of the serial wind turbine generator under the optimized control strategy; delta Pechu1At 0 < t0In time period, the output of the serial energy storage system under the optimized control strategy; delta Pebin1At 0 < t0In time period, the output of the parallel energy storage system under the control strategy is optimized; delta Pwbin1At 0 < t0In time interval, parallel wind turbine generator output is performed under an optimized control strategy;k1 is a task distribution coefficient of the energy storage system when the wind storage combined system adopts a parallel control strategy to respond to the frequency modulation command; delta Pw+eThe method comprises the steps of modulating frequency task quantity for a wind storage combined system; delta Pvir-ine1At 0 < t0In time interval, the virtual inertia of the wind turbine generator is used for adjusting power; delta Pchange-β1At 0 < t0And in time period, the variable pitch control of the fan adjusts the power.
in the formula: delta Pchu2Is at t0In the time period of T being less than T, the serial output condition of the wind storage combined system is optimized under the control strategy; delta Pbin2Is at t0In the time period of T being less than T, the parallel output condition of the wind storage combined system is optimized under the control strategy; delta Pwchu2Is at t0In the time period of T being less than T, the output of the serial wind turbine generator is optimized under the control strategy; delta Pechu2Is at t0In the time period of T being less than T, the output of the serial energy storage system under the control strategy is optimized; delta Pebin2Is at t0In the time period of T being less than T, the output of the parallel energy storage system is optimized under the control strategy; delta Pwbin2Is at t0In the time period of T being less than T, the output of the parallel wind turbine generator is optimized under the control strategy; k1When a parallel control strategy is adopted for the wind storage combined system to respond to the frequency modulation command, the task distribution coefficient of the energy storage system is obtained; delta Pw+eThe method comprises the steps of modulating frequency task quantity for a wind storage combined system; delta Pvir-ine2In the time period of T0 being more than T and less than T, the virtual inertia of the wind turbine generator adjusts power; delta Pchange-β2Is at t0And when T is less than T, the variable pitch control of the fan adjusts the power.
Has the advantages that: compared with the prior art, the invention has the following advantages: (1) the problem of how to reasonably distribute energy between the energy storage system and the wind power after a frequency modulation instruction is issued is comprehensively considered, and the energy storage rapidity can be utilized in the starting stage of the traditional frequency modulation standby unit by combining the serial and parallel control modes of the wind storage system, so that the required output of system frequency modulation is basically achieved within 0.3s, and the frequency modulation effect is ensured; (2) the wind storage system is accurately modeled, serial frequency modulation task components are obtained by optimizing through a genetic algorithm, and switching time is obtained through simulation, so that the frequency modulation precision is improved; (3) after the traditional unit is started, the energy storage action amount can be reduced by the optimization control strategy, the energy storage service time is prolonged, and the frequency modulation economy is improved.
Drawings
FIG. 1 is a schematic diagram of primary frequency control of a wind storage system according to the present invention;
FIG. 2 is a flow chart of the energy storage system capacity configuration of the present invention;
FIG. 3 is a comparison of energy storage output under different control strategies
FIG. 4 is a comparison of wind power output under different control strategies;
FIG. 5 is a comparison of conventional unit output under different control strategies;
fig. 6 is a comparison graph of the frequency modulation effect under the control strategy of the present invention.
Detailed Description
The technical solution of the present invention is further described below with reference to the accompanying drawings and examples.
The wind storage system auxiliary power grid primary frequency modulation control method based on the series-parallel structure is shown in figure 1, comprehensively considers the problem of how to reasonably distribute energy between an energy storage system and wind power after a frequency modulation instruction is issued, provides a wind storage system serial parallel combined control mode, and comprehensively utilizes an energy storage system parallel and serial control strategy to provide a wind storage frequency modulation optimization control strategy. The specific frequency modulation control method comprises the following steps:
(1) and acquiring the actual frequency of the power system, and calculating the frequency deviation of the current system.
(2) Establishing a wind storage system model, calculating a serial frequency modulation task component K and a time (switching time) t for switching the system from serial frequency modulation to parallel frequency modulation0(ii) a The invention establishes a wind storage system model with a series-parallel mixed structure。
Wherein the serial FM task component K and the switching time t0The calculation method of (2) is as follows:
(21) modeling a wind turbine generator and an energy storage system in the system, and respectively establishing serial and parallel models of the wind turbine generator and the energy storage system;
(a) modeling of wind turbine generator
The current mainstream wind generating set does not have inertia response capability, and the capability of participating in frequency modulation of the fan can be ensured only by adopting a certain technical means. At present, the mainstream control modes are virtual inertia control and pitch control, and both the virtual inertia control and the pitch control simulate the traditional frequency response in a power system by changing the active output of a wind turbine generator.
The virtual inertia control simulates the internal inertia response process of the synchronous generator, the mechanical power is kept constant due to time delay because the rotating speed of the generator set cannot change suddenly, and the rotating speed of the rotor is reduced due to the sudden increase of the electromagnetic power, so that the rotating kinetic energy is released, and the frequency reduction rate of the system is reduced.
The variable pitch control is a control method for the wind driven generator, which enables the wind driven generator to achieve the maximum wind energy utilization rate by adjusting the blade angle and controls the balance of power and rotating speed under different wind conditions.
The transfer function is specifically as follows:
"virtual inertial control" transfer function:
in equation (1): k is a radical ofvdIs a virtual inertial response coefficient, generally takes 8; t iswind1Is an inertia response time constant, generally takes a value of 0.1s, and s represents a laplacian operator; delta Pwind1Representing the power change of the system under virtual inertial control; Δ f represents a frequency deviation;
pitch control transfer function:
in equation (2): k is a radical ofchangeIs a primary frequency modulation coefficient, generally takes the value of 20; t iswind2Is the variable pitch time constant, generally takes 3 s: s represents the laplacian operator; delta Pwind2Representing the power change of the system under the pitch control; Δ f represents a frequency deviation;
wind turbine generator virtual frequency response transfer function:
in equation (3): k is a radical ofvdIs the virtual inertial response coefficient; k is a radical ofchangeIs the primary frequency modulation coefficient; t iswind1Is the virtual inertial response time constant; t iswind2Is the pitch time constant; s represents the laplacian operator; gwRepresenting a wind turbine generator virtual frequency response transfer function; coefficient of primary frequency modulation kchangeThe value is typically 20, depending on the system.
(b) Energy storage system modeling
The energy storage system has the technical advantages of quick response, stable operation and four-quadrant operation, and the energy storage system with a certain capacity configured in the wind power plant can meet the frequency modulation requirement of the power system to the greatest extent. Because the energy storage system is configured in the wind power plant, the inertia response coefficient and the primary frequency modulation coefficient of the energy storage system are basically the same as those of the wind turbine generator. The energy storage system transfer function model is therefore:
in equation (4): t isEnergyThe response time of the energy storage system is generally 0.3 s; k is a radical ofvdIs the virtual inertial response coefficient; k is a radical ofchangeIs the primary frequency modulation coefficient; s represents the laplacian operator; gwRepresenting a wind turbine generator virtual frequency response transfer function; delta PEnergyRepresenting an energy storage power adjustment value; Δ f represents a frequency deviation.
(c) And respectively establishing serial and parallel models of the wind turbine generator and the energy storage system.
(22) Establishing an optimal control objective function of the wind storage system;
and the cost of the energy storage system and the serial and parallel frequency modulation effect constraints are considered, and an optimal control mode of the wind storage system is provided. In the starting stage of the traditional frequency modulation standby resource and the wind turbine generator, the parallel strategy ratio is changed according to different wind power permeability rates, and the frequency modulation effect is ensured; after the traditional unit and the wind turbine generator are started, the control mode is switched from the mode of mainly using serial frequency modulation to the mode of mainly using parallel frequency modulation, and the action amount of the energy storage system and the service life loss of the energy storage system are reduced. Therefore, the optimal control objective function of the air storage system is provided as follows:
min[C1·Δfdev+C2·Δfsta+C3·S] (5)
in equation (5): c1A penalty factor of the lowest frequency point is 0.25; c2A penalty factor of a steady-state frequency value is taken as 0.25; c3A frequency energy storage action amount penalty factor is taken as 0.5; Δ fdevIs the lowest point of frequency; Δ fstaIs the steady state frequency value; and S is the cost of the energy storage system in the primary frequency modulation process, which comprises four parts of the construction cost of the energy storage system, the operation cost of the energy storage system, the maintenance cost of the energy storage system and the electricity purchasing cost of the primary frequency modulation when the primary frequency modulation of the power system is carried out. The functional relationship is as follows:
S＝S1+S2+S3+S4 (6)
in equation (6): s1Construction costs for wind storage systems; s2The operating cost of the wind storage system is reduced; s3Cost for energy storage system maintenance; s4The electricity purchasing cost for the energy storage system to participate in primary frequency modulation is reduced.
(23) And searching the optimal solution of the wind storage system optimization control objective function by adopting a genetic algorithm to obtain the optimal serial frequency modulation task component K. And solving by taking the serial distribution ratio K of the wind storage system as a variable under the condition of establishing an optimal control objective function of the wind storage system. In the embodiment, the serial distribution ratio K is optimized by adopting a genetic algorithm, the initial population number is set to be 50, and the model is solved to obtain the optimal solution of the serial distribution ratio K.
(24) Time (switching time) t for switching system from serial frequency modulation to parallel frequency modulation0The determination method of (2) is as follows:
A. input t0When the frequency deviation is equal to 0 (simulation initial time), simulating a calculation result, and counting the maximum value of the frequency deviation and the steady-state frequency value;
B. comparing the initially set frequency deviation maximum value and the steady-state frequency value with the frequency deviation maximum value and the steady-state frequency value calculated by the simulation program through the program, and storing the smaller frequency deviation maximum value and the smaller steady-state frequency value;
C. judging whether a primary frequency modulation period is satisfied, if not, t0Continuing to execute the loop by adding a sampling period;
D. when the maximum value of frequency deviation and the minimum value of steady-state frequency are obtained, t0The corresponding value of (a).
And carrying out capacity configuration on the energy storage system under different control strategies, wherein a capacity configuration flow chart is shown in FIG. 2. The specific process is as follows:
A.T, importing first frequency modulation data;
B. according to the output data P of the energy storage system at each moment1Determining the rated power P of the energy storage system by considering all relevant constraints in the actual operation of the energy storage system0；
C. Integrating the energy storage system processing curve on a time axis according to the output of the energy storage in the frequency modulation time period to obtain the capacity Ef；
D. Determining the rated capacity E of the energy storage system by considering the constraint condition of the SOC of the energy storage system0；
E.T＝T+1。
(3) Taking serial frequency modulation control as a main part, respectively calculating the output of the wind turbine generator and the energy storage system according to the serial frequency modulation task component K obtained in the step (2) according to the frequency deviation of the system, and issuing the task to the wind turbine generator and the energy storage system for primary frequency modulation; reaches the switching time t0The parallel frequency modulation control is mainly used, namely the parallel frequency modulation task component is equal to K, and the serial frequency modulation task is controlled to be in seriesAnd (4) respectively calculating the output of the wind turbine generator and the energy storage system, and issuing the task to the wind turbine generator and the energy storage system for primary frequency modulation, wherein the service component is 1-K.
When the wind storage system adopts an optimized control strategy, the total output of the wind storage combined system is
In equation (7):
for optimizing the control strategy, t is more than 0 and less than t0Outputting power by the wind storage combined system in a time interval;
for optimizing control strategy at t0The wind storage combined system outputs power in a time period of T; t is the primary frequency modulation maintaining time, which is taken for 30 s.
At 0 < t0The time-interval output condition is shown in equation (8):
wherein, Δ Pchu1At 0 < t0In time period, optimizing the serial output condition of the wind storage combined system under the control strategy; delta Pbin1At 0 < t0In time period, optimizing the parallel output condition of the wind storage combined system under the control strategy; delta Pwchu1At 0 < t0Output delta P of serial wind turbine generator under time interval and optimized control strategyechu1At 0 < t0In time period, the output of the serial energy storage system under the optimized control strategy; delta Pebin1At 0 < t0In time period, the output of the parallel energy storage system under the control strategy is optimized; delta Pwbin1At 0 < t0In time interval, parallel wind turbine generator output is performed under an optimized control strategy; delta Pw+eThe unit is MW for the frequency modulation task quantity of the wind power storage combined system; delta Pvir-ine1At 0 < t0In time interval, the virtual inertia of the wind turbine generator adjusts power, MW; delta Pchange-β1At 0 < t0In time interval, the variable pitch control of the fan adjusts power, MW; k1When the wind storage combined system adopts a parallel control strategy alone to respond to the frequency modulation command, the frequency modulation task distribution coefficient of the energy storage system, in this example, the energy storage frequency modulation distribution coefficient K1And the energy storage system task allocation coefficient is determined by taking the minimum frequency deviation as a constraint condition, and the value is 0.5.
Wherein, Δ Pvir-ine1、ΔPchange-β1The determination method comprises the following steps:
Cp＝Cp(β1+Δβ1) (11)
wherein m is the mass of the fan, kg; v is the rotating speed of the fan, m/s; Δ t1Is the virtual inertial response time, s; rho is air density and is 1.29kg/m under standard conditions3；R1Is the swept area radius, m; vmIs wind speed, m/s; cpThe wind energy utilization coefficient is generally 20-30%, in this example 25%; beta is a1At 0 < t0In time interval, the windward pitch angle of the fan under the parallel control strategy; delta beta 1 is 0 < t0And in time interval, the variation of the windward pitch angle of the fan is controlled in series.
Wherein, Δ Pvir-ine2、ΔPchange-β2The determination method comprises the following steps:
Cp＝Cp(β2+Δβ2) (15)
in formulas (13) to (15), m is the mass of the fan in kg; v is the rotating speed of the fan, m/s; Δ t1Is the virtual inertial response time, s; rho is air density and is 1.29kg/m under standard conditions3；R1Is the swept area radius, m; vmIs wind speed, m/s; cpThe wind energy utilization coefficient is generally 20-30%, in this example 25%; beta 2 is at t0In the time period of T being less than T, the windward pitch angle of the fan under the parallel control strategy; Δ β 2 is t0And in the time period of T being less than T, serially controlling the variation of the windward pitch angle of the fan.
Based on the actual data of the power grid in a certain area of Liaoning, a primary frequency modulation simulation model of the power system is established in MATLAB/Simulink (R2014b) according to the wind storage system primary frequency modulation control method based on the series-parallel structure, and the specific parameters of the model are as follows: the load is 1000MW, the rated power of the wind farm is 200MW, and the load disturbance is 100MW (0.1 p.u.). Calculating the time t when the serial frequency modulation task component K converges to 0.85 and the serial frequency modulation is mainly changed into the parallel frequency modulation0The value converged to 4.5s after the disturbance occurred.
After the power system is disturbed, the specific output condition of the wind storage combined system has important significance for understanding the frequency modulation process; meanwhile, the effectiveness of the strategy can be verified in the process that the energy storage system participates in the frequency modulation output of the power grid under different control strategies. Therefore, the output conditions of the energy storage system and the wind power plant under the serial, parallel and optimized control strategies are verified in a simulation mode.
(1) Output of energy storage system
The energy storage system participating in the power grid frequency modulation output process under different control strategies has important significance for verifying the effectiveness of the strategies. Therefore, under the same disturbance, the frequency modulation output condition of the energy storage system under the parallel, serial and optimized control strategy is simulated, and the simulation result is shown in fig. 3.
When the traditional frequency modulation standby resource is started, the energy storage system quickly responds to frequency change after the power system is disturbed, the output of the energy storage system is rapidly increased from 0, and about 0.3s is needed to reach the maximum output. Under different control strategies, the maximum value of the parallel control output can reach 0.032p.u., the serial control output can reach 0.023p.u., and the energy storage output under the optimized control can reach 0.03p.u. Therefore, the parallel control and the optimized control of the energy storage system can provide larger energy support in the initial period of disturbance occurrence, and the frequency lowest point is lowered.
After the traditional frequency modulation standby resource is started, the output of the parallel control energy storage system is stabilized at 0.019p.u., the output of the serial control energy storage system is basically 0, and the output of the optimization control energy storage system is stabilized at 0.0037p.u. At the moment, the output of the energy storage system is very small under serial and optimal control, the energy storage action amount can be reduced, the service life of the energy storage system is prolonged, and meanwhile, a margin is reserved for the next frequency modulation.
(2) Wind power plant output
The wind power plant is used as an important primary frequency modulation standby resource, the output process of the wind power plant in primary frequency modulation is researched, and the wind power plant has important significance for verifying serial and parallel control strategies. Therefore, the simulation is verified, and the simulation result is shown in FIG. 4
In the starting stage of the wind turbine generator, the wind power plant virtual inertia response under each control strategy releases the kinetic energy of the fan rotor within about 0.1s, so that the rapid frequency drop of the power system is delayed, and the control strategy has small influence on the process;
in the variable pitch control process, because the wind power bearing tasks are different in different control strategies, the control effects of the different control strategies begin to be reflected. In serial control, wind power serves as a main standby resource of a wind storage system, and the wind power output is the largest and can basically reach 0.02 p.u.; in parallel control, because the wind power and the energy storage system respond to the frequency modulation instruction in parallel, the output is small, and is about 0.015 p.u.; under the optimization control strategy, the output of the wind turbine generator is about 0.0197p.u. Therefore, the wind power frequency modulation capability can be better utilized by the optimized control and the serial control, and the energy storage action amount is reduced.
(3) Traditional frequency modulation resource contribution
The traditional frequency modulation standby resource is used as a main body of the frequency modulation of the power system and has important influence on the frequency modulation. The influence of different control strategies on the output of the conventional frequency modulation standby resource is analyzed in a simulation manner, which is specifically shown in fig. 5.
The parallel control strategy seriously occupies the output of the traditional frequency modulation standby resource due to the parallel control of the energy storage system, and cannot completely utilize the frequency modulation capability of the traditional frequency modulation standby resource, so that the output of the traditional frequency modulation standby resource is about 0.067 p.u.; after the traditional frequency modulation standby unit is started, the output of the energy storage system is reduced to a certain extent by the optimization control strategy and the serial control strategy, and the output of the traditional unit is respectively 0.073p.u. and 0.0736p.u. under the optimization and serial control strategies. Therefore, the frequency modulation capability of the traditional frequency modulation unit can be well utilized by the optimized control and the serial control.
In conclusion, the wind storage system adopts an optimized control mode, and the energy storage system can rapidly output power and improve the lowest frequency point in the starting stage of the traditional frequency modulation unit; after the traditional unit is started, the output of the energy storage system can be reduced, the service life loss of the energy storage system is reduced, and the economy of primary frequency modulation is improved.
(4) Frequency modulation effect under different control strategies
In order to research the frequency modulation effect of the energy storage system under different control strategies, simulation verification is performed in Simulink, and the simulation result is shown in FIG. 6.
Under the same power system disturbance, the energy storage system participates in the power system frequency modulation in parallel to optimize a control strategy, and then the control strategy is optimized. The lowest point of the primary frequency modulation frequency and the steady-state frequency deviation of the power system under different control strategies are shown in table 1.
TABLE 1 statistical table of frequency deviation under different control strategies
| Control strategy | Lowest frequency (Hz) | Steady state frequency value (Hz) |
| Energy storage system series | -0.442 | -0.241 |
| Energy storage systemUnified parallelism | -0.387 | -0.187 |
| Optimizing control | -0.401 | -0.205 |
In general, the optimization control strategy provided by the invention can provide active support for a power system by using the rapidity of an energy storage system in the starting stage of a traditional unit and wind power; after the unit is started, on the premise of utilizing the frequency modulation capability of the unit to the maximum extent, the energy storage action amount is reduced, the service life of an energy storage system is prolonged, the lowest point of frequency is improved to the maximum extent, and the frequency quality of an electric power system is maintained.
Claims (6)
1. A wind storage system auxiliary power grid primary frequency modulation control method based on a series-parallel structure is characterized by comprising the following steps:
(1) acquiring the actual frequency of the power system, and calculating the frequency deviation of the current system;
(2) establishing a wind storage system model, calculating a serial frequency modulation task component K and the switching time t of the system0；
(3) Taking serial frequency modulation control as a main part, respectively calculating the output of the wind turbine generator and the energy storage system according to the serial frequency modulation task component K obtained in the step (2) according to the frequency deviation of the system, and issuing the task to the wind turbine generator and the energy storage system for primary frequency modulation; reaches the switching time t0And then, switching to the mode that parallel frequency modulation control is mainly used, namely the serial frequency modulation task component is 1-K, the parallel frequency modulation task component is K, respectively calculating the output of the wind turbine generator and the energy storage system, and transmitting the task to the wind turbine generator and the energy storage system for primary frequency modulation.
2. Wind storage system assistance according to claim 1 based on a hybrid architectureThe power grid primary frequency modulation control method is characterized in that the serial frequency modulation task component K in the step (2) and the switching time t of the system0The calculation method of (2) is as follows:
(21) modeling a wind turbine generator and an energy storage system in the system, and respectively establishing serial and parallel models of the wind turbine generator and the energy storage system;
(22) establishing an optimal control objective function of the wind storage system;
(23) searching an optimal solution of an optimal control objective function of the wind storage system by adopting a genetic algorithm to obtain an optimal serial frequency modulation task component K;
(24) simulating the system, traversing time variable, and switching time t0Corresponding to the time value when the frequency deviation is maximum and the steady state frequency value is minimum.
3. The primary frequency modulation control method for the auxiliary power grid of the wind power storage system based on the series-parallel structure as claimed in claim 2, wherein in the step (21), the wind turbine generator and the energy storage system are modeled, and the virtual frequency response transfer function of the wind turbine generator is as follows:
wherein k isvdIs the virtual inertial response coefficient; k is a radical ofchangeIs the primary frequency modulation coefficient; t iswind1Is the virtual inertial response time constant; t iswind2Is the pitch time constant; s represents the laplacian operator; gwRepresenting a wind turbine generator virtual frequency response transfer function;
the energy storage system transfer function is:
wherein k isvdIs the virtual inertial response coefficient; k is a radical ofchangeIs the primary frequency modulation coefficient; t isEnergvThe energy storage output response time constant; s represents the laplacian operator.
4. The primary frequency modulation control method for the auxiliary power grid of the wind power storage system based on the series-parallel structure is characterized in that the establishing of the wind power storage system optimization control objective function in the step (22) is as follows:
min[C1·Δfdev+C2·Δfsta+C3·S]
wherein, C1As a frequency nadir penalty factor, C2Penalty factors for steady-state frequency values, C3For frequency energy storage action penalty factor, Δ fdevIs the lowest point of frequency,. DELTA.fstaAnd S is the sum of the construction cost of the energy storage system, the operation cost of the energy storage system, the maintenance cost of the energy storage system and the electricity purchasing cost of primary frequency modulation.
5. The wind power storage system auxiliary power grid primary frequency modulation control method based on the series-parallel structure is characterized by comprising the following steps of: the penalty factor of the lowest frequency point is 0.25, the penalty factor of the steady-state frequency value is 0.25, and the penalty factor of the frequency energy storage action amount is 0.5.
6. The primary frequency modulation control method for the auxiliary power grid of the wind storage system based on the series-parallel structure as claimed in claim 1, wherein the calculation of the output of the current wind turbine generator and the energy storage system in step (3) is divided into 0 < t0Time period and t0The output of the wind storage combined system is less than T and T, T is the primary frequency modulation maintaining time,
at 0 < t0The output of the time interval wind storage combined system is as follows:
wherein,
at 0 < t0Output, Δ P, of a time-interval wind-storage combined systemchu1Serial output conditions in the wind storage combined system are obtained; delta Pbin1At 0 < t0In time period, the parallel output condition of the wind storage combined system; delta Pwchu1At 0 < t0The output of the serial wind turbine generator in time interval; delta Pechu1At 0 < t0The output of the time interval serial energy storage system; delta Pebin1At 0 < t0The output of the time-interval parallel energy storage system; delta Pwbin1At 0 < t0The output of the wind turbine is parallel in time interval; k1Adopting a parallel control strategy for the wind storage combined system to respond to the task allocation coefficient of the energy storage system when the frequency modulation instruction is received; delta Pw+eThe method comprises the steps of modulating frequency task quantity for a wind storage combined system; delta Pvir-ine1At 0 < t0Adjusting power of the wind turbine generator by virtual inertia in a time interval; delta Pchange-β1At 0 < t0In time period, the variable pitch of the fan is controlled to regulate power;
at t0The output of the wind storage combined system in the time period of T < T is as follows:
wherein,
at t0The output of the wind storage combined system is delta P in the time interval of Tchu2Is at t0The serial output condition of the wind storage combined system is less than T and less than T; delta Pbin2Is at t0In the time period of T being less than T, the wind storage combined system outputs power in parallel; delta Pwchu2Is at t0The output of the serial wind turbine generator is less than T and less than T; delta Pechu2Is at t0The output of the serial energy storage system is less than T and less than T; delta Pebin2Is at t0The output of the parallel energy storage system is less than T and less than T; delta Pwbin2Is at t0The output of the parallel wind turbine is in the time period of T < T; k1Parallel control strategy for wind storage combined systemWhen a frequency modulation command is received, the task distribution coefficient of the energy storage system is obtained; delta Pw+eThe method comprises the steps of modulating frequency task quantity for a wind storage combined system; delta Pvir-ine2Is at t0In the time period of T being less than T, the virtual inertia of the wind turbine generator adjusts the power; delta Pchange-β2Is at t0And when T is less than T, the variable pitch control of the fan adjusts the power.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910634025.XA CN110350554B (en) | 2019-07-12 | 2019-07-12 | Wind storage system auxiliary power grid primary frequency modulation control method based on series-parallel structure |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910634025.XA CN110350554B (en) | 2019-07-12 | 2019-07-12 | Wind storage system auxiliary power grid primary frequency modulation control method based on series-parallel structure |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN110350554A CN110350554A (en) | 2019-10-18 |
| CN110350554B true CN110350554B (en) | 2022-03-29 |
Family
ID=68176207
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910634025.XA Active CN110350554B (en) | 2019-07-12 | 2019-07-12 | Wind storage system auxiliary power grid primary frequency modulation control method based on series-parallel structure |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110350554B (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111754361B (en) * | 2020-06-29 | 2022-05-03 | 国网山西省电力公司电力科学研究院 | Energy storage capacity optimal configuration method and computing device of wind-storage combined frequency modulation system |
| CN112821427B (en) * | 2021-02-23 | 2023-03-07 | 西安交通大学 | Distributed frequency modulation auxiliary service system design method |
| CN118281908B (en) * | 2024-06-04 | 2024-08-23 | 江苏航运职业技术学院 | Frequency modulation cooperative control method and system for wind power-energy storage system |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2016082070A1 (en) * | 2014-11-24 | 2016-06-02 | Abb Technology Ltd | Method for black starting wind turbine, wind farm, and restoring wind farm and wind turbine, wind farm using the same |
| CN108306331A (en) * | 2018-01-15 | 2018-07-20 | 南京理工大学 | A kind of Optimization Scheduling of wind-light storage hybrid system |
| CN108493962A (en) * | 2018-05-22 | 2018-09-04 | 南京赫曦电气有限公司 | A kind of devices and methods therefor for generating set frequency modulation |
-
2019
- 2019-07-12 CN CN201910634025.XA patent/CN110350554B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2016082070A1 (en) * | 2014-11-24 | 2016-06-02 | Abb Technology Ltd | Method for black starting wind turbine, wind farm, and restoring wind farm and wind turbine, wind farm using the same |
| CN108306331A (en) * | 2018-01-15 | 2018-07-20 | 南京理工大学 | A kind of Optimization Scheduling of wind-light storage hybrid system |
| CN108493962A (en) * | 2018-05-22 | 2018-09-04 | 南京赫曦电气有限公司 | A kind of devices and methods therefor for generating set frequency modulation |
Non-Patent Citations (4)
| Title |
|---|
| Control strategy of energy storage system for power stability in a wind farm;Yun-Hyun Kim et al.;《8th International Conference on Power Electronics - ECCE Asia》;20110707;第2970-2973页 * |
| Optimal Configuration of Energy Storage System Coordinating Wind Turbine to Participate Power System Primary Frequency Regulation;Junhui Li et al.;《ENERGIES》;20180530;第1-16页 * |
| 平抑风电功率波动及负荷调峰的VRB储能应用;林 琳等;《浙江电力》;20190531;第38卷(第5期);第25-30页 * |
| 考虑储能参与调频的风储联合运行优化策略;胡泽春等;《电网技术》;20160831;第40卷(第8期);第2251-2257页 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN110350554A (en) | 2019-10-18 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| WO2021164112A1 (en) | Frequency control method and system during using wind farm as black-start power source by means of optimal configuration of energy storage | |
| CN109103893B (en) | Auxiliary frequency modulation method for cluster temperature control load participating in power grid AGC | |
| CN110350554B (en) | Wind storage system auxiliary power grid primary frequency modulation control method based on series-parallel structure | |
| CN103606108B (en) | It is applicable to speed governing simulation system and the method for pump-storage generator | |
| Meng et al. | Energy storage auxiliary frequency modulation control strategy considering ACE and SOC of energy storage | |
| CN115102239B (en) | Energy storage power station primary frequency modulation control method and system considering SOC balance | |
| CN105006846A (en) | Station level active power optimization method of wind power station | |
| CN102611132B (en) | Method for adjusting parameters of additional frequency controller of double-fed variable-speed wind turbine generator | |
| CN116581780A (en) | Primary frequency modulation characteristic modeling and control method for wind-storage combined system | |
| CN114784854A (en) | Wind storage combined power station participating frequency modulation optimization control method, system, equipment and medium | |
| CN114243760A (en) | Photovoltaic energy storage coordination configuration method suitable for power distribution network | |
| CN114336694A (en) | Energy optimization control method for hybrid energy storage power station | |
| CN111478310A (en) | Direct-current distribution network virtual inertia control method based on variable droop coefficient | |
| CN115864429A (en) | Multi-objective optimization AGC method for wind and fire storage cooperation under double-carbon target | |
| CN114844118A (en) | Multi-type equipment power coordination control method and system suitable for micro-grid | |
| CN117154756B (en) | Wind-energy-storage combined frequency modulation control method considering energy storage charge state | |
| CN110417033B (en) | Extra-high voltage direct current transmission system cooperative frequency modulation control method and system | |
| Li et al. | Design of control strategy and effect evaluation for primary frequency regulation of wind storage system | |
| CN111523947A (en) | Virtual power plant power generation cost generation method | |
| CN116345486A (en) | Model predictive control-based primary frequency modulation coordination control method and device in wind field | |
| CN111049180A (en) | Island microgrid voltage frequency control method and system based on hybrid energy storage | |
| CN115102228A (en) | Multi-target coordination frequency optimization method and device for wind power plant containing flywheel energy storage | |
| CN113592125B (en) | Matching optimization comparison selection method and system for extra-high voltage direct current matched power supply | |
| CN114629135A (en) | Wind storage frequency modulation capacity adjusting method and device, computer equipment and storage medium | |
| CN116345583B (en) | Power grid power supply power adjusting method and system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |