CN103337855B - Electrical network operation risk assessment method of wind electricity large-scale tripping - Google Patents
Electrical network operation risk assessment method of wind electricity large-scale tripping Download PDFInfo
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Abstract
The invention provides an electrical network operation risk assessment method of a wind electricity large-scale tripping. The method comprises the following steps of: simulation of a wind electricity large-scale tripping accident caused by a fault, a risk assessment of electrical network transient stability after disturbance, the risk assessment of system frequency stability after the disturbance, and the risk assessment of voltage stability after the disturbance. The method of the invention quantizes the risk of the wind electricity large-scale tripping from each aspect of the electrical network operation, so that the effects of preventing the wind electricity tripping and improving the electrical network safety are achieved.
Description
Technical field
The invention belongs to field of power, be specifically related to a kind of network operation risk assessment method of wind electricity large-scale off-grid.
Background technology
In order to realize the grand energy strategy of low-carbon (LC), environmental protection, green and sustainable development, China greatly developed regenerative resource in recent years, put into effect a series of standard and policy for regenerative resource, State-level gives strong support, and regenerative resource obtains tremendous development.Especially wind-powered electricity generation, the multiple million kilowatt wind power base of China has been built and has accessed operation of power networks, eight ten million multikilowatt wind power base of planning also just progressively carry out construction, the development mode of China's wind-powered electricity generation is different from abroad, " to concentrate access, high pressure long-distance sand transport on a large scale, to dissolve on a large scale ", " to disperse access on a large scale, on-site elimination " is auxiliary pattern.
In recent years, wind-powered electricity generation increases scale newly and speed is in first place, the world, wind-powered electricity generation fast development brings enormous benefits to society, but this wherein also also exists risk: one is that wind-electricity integration standard is progressively implemented from State-level, to also not rectifying and improving according to the wind-powered electricity generation that standard is grid-connected, but on the whole, Wind turbines regulation and control level is very different, as compared the low-voltage, high voltage crossing ability etc. of care, this just causes the phenomenon of grid disturbance wind-powered electricity generation off-grid to occur; Two is core technologies of wind-powered electricity generation, as current transformer and relevant to current transformer etc. meritorious, idle control technology etc. are not grasped completely, introduction of foreign technology adds Wind turbines manufacturing cost, in order to save cost, when putting into operation, meritorious, the idle control of Wind turbines and lowly to wear, height is worn etc., and function is often had a greatly reduced quality, simultaneously, also certain gap etc. is there is with expection with technical specification and practical functions etc. such as the dynamic reactive compensation devices that wind energy turbine set is supporting, to sum up, be difficult to preferably for the dynamic security of electrical network provides support after wind-electricity integration; Three is due to Wind Power Development excessive velocities, there is electric component configuration, design in electric field construction quality and field unavoidably and there is the hidden danger such as unreasonable, as the construction quality of main element cable in wind field, protection for feed line coordinate with blower fan protection seting inharmonious etc., these are the cause of wind electricity large-scale off-grid or inducement often; Four is China's Wind Power Generations is to concentrate grid-connected, high pressure long-distance sand transport on a large scale; be different from external development mode; scale field group's effect and all there is particularity with the coupling of bulk power grid; the chain off-grid of easy initiation scale; all do not have experience can supply to use for reference from planning aspect, operation aspect, wind-powered electricity generation off-grid is to the impact increased risk of electricity net safety stable.
Due to the comprehensive function of the above-mentioned multiple hidden danger that wind-powered electricity generation fast development brings, the risk of the extensive off-grid of wind power base generation blower fan is caused to increase, and wind electricity large-scale, centrality is more outstanding, the probability that chain off-grid occurs is also larger, simultaneously with grid reciprocation, to the impact that power network safety operation brings, affect larger, as 2.24 of Jiuquan wind power base generation in 2011, 4.3, 4.17, 4.25 accidents such as off-grid such as large-scale wind power such as series such as grade, accident causes 598 respectively, 400, 677, 1278 Fans off-grids, off-grid wind-powered electricity generation capacity is respectively 840MW, 568MW, 975MW and 1535MW, on April 17th, 2011 also there is Wind turbines scale off-grid in Zhangbei County's wind power base, and off-grid number of units is 644, capacity is 854MW, and the extensive off-grid accident of wind-powered electricity generation of above-mentioned generation all brings greater impact to electrical network, has had influence on power network safety operation.In order to prevention and control wind-powered electricity generation off-grid better and the safe and stable operation of electrical network after guaranteeing off-grid; be necessary to propose a kind of network operation risk assessment method for wind electricity large-scale off-grid; the impact and influence that quantitative evaluation off-grid brings to electrical network is carried out from the multiple side of power network safety operation, and then prevention and control in addition targetedly.
Due to China's Wind Power Development excessive velocities, and wind-powered electricity generation planning construction and Electric Power Network Planning, blower fan manufacture, Grid-connection standards, construction quality etc. is inharmonious, under large-scale wind power concentrates access high pressure to send scene of dissolving at a distance outside, very easily there is the extensive off-grid of Wind turbines because disturbance causes, and then impact bulk power grid safety.
Summary of the invention
In order to overcome above-mentioned the deficiencies in the prior art; the invention provides a kind of network operation risk assessment method of wind electricity large-scale off-grid; quantize the risk that the extensive off-grid of wind-powered electricity generation brings from each side of operation of power networks, and then play the effect of prevention and control wind-powered electricity generation off-grid, lifting power grid security.
In order to realize foregoing invention object, the present invention takes following technical scheme:
A kind of network operation risk assessment method of wind electricity large-scale off-grid is provided, said method comprising the steps of:
Step 1: simulated failure causes the accident scene of wind electricity large-scale off-grid;
Step 2: the risk assessment carrying out Power Network Transient Stability after disturbance;
Step 3: the risk assessment carrying out system frequency stability after disturbance;
Step 4: the risk assessment carrying out voltage stability after disturbance.
Described step 1 comprises the following steps:
Step 1 ?1: based on bulk power grid PSD ?BPA emulation platform set up bulk power grid Static Power Flow computation model and bulk power grid multilayer output feedback network model;
Step 1 ?2: simulating grid fault causes the disturbance of wind electricity large-scale off-grid.
Described step 1 ?in 1, bulk power grid Static Power Flow computation model comprises generator model, load model, transformer model and circuit model; Bulk power grid multilayer output feedback network model comprises the generator transient Model based on generator dynamic element, and described generator transient Model comprises twin shaft model, excitation model, power system stabilizer, PSS model, governor model and prime mover model.
Described step 1 ?2 to comprise the following steps:
1) the electric component place of simulation wind energy turbine set, bulk power grid causes the fault of wind-powered electricity generation off-grid, comprises symmetrical short-circuit fault, asymmetry short circuit fault and disconnection fault;
2) there is rear relaying protection regular event in simulated failure, excision fault element, and the scene of wind-powered electricity generation off-grid occurs after postponing blink;
3) Wind turbines is simulated according to designated capabilities, the scene of specifying number of units scale off-grid.
In described step 2, the Power Network Transient Stability under the fault generation of assessment electrical network main road and subsequently wind electricity large-scale off-grid dual-impingement, its instability forms comprises merit angle step-out aperiodic and vibration step-out.
System is equivalent to one machine infinity bus system, if establish original machine power P
m, generator internal e.m.f. E and Infinite bus system voltage U ' be constant, ignore line resistance and distributed capacitance, total apparent reactance of system is X
Σ;
Minor interference is stood and linearisation near working point for Infinite bus system, then has Incremental Equation:
Wherein, δ is generator amature angle; δ
0for the generator amature angle at steady operation point place; P
mfor original machine power; P
efor Generator end electromagnetic power; M is inertia time constant; ω is generator speed; K is synchronising torque coefficient, and
Can obtain system features equation by formula (1) is
Mp
2+K＝0 (2)
Equation (2) is had:
1) if K>0, then characteristic root is
ω
nfor generator amature during system undamped is relative to the natural frequency of oscillation of Infinite bus system, when taking into account mechanical damping, system stability;
2) if K<0, then
characteristic root has a positive real root, and system is unstable, and its instability forms is aperiodicity step-out;
3) if K=0, be then zero repeated root, system is positioned at critical condition, and real system does not allow to run in critical condition;
In described step 3, after Wind turbines scale off-grid, system power generation vacancy, vacancy power is redistributed at each generator according to the synchronizing power coefficient of each generator and moment of inertia, generator electromagnetic power changes, because inertia time constant is larger, in this time scale, the mechanical output of unit prime mover remains unchanged, the imbalance of generator electromagnetic power and mechanical output makes generator speed change, when generator speed change and when entering into the mean speed of system, Generator Governor starts to respond rotation speed change, and change exerting oneself of unit further by its characteristic, take into account the functions combination effect of load simultaneously, finally by the comprehensive power frequency characteristic decision systems frequency of system,
Power shortage after wind electricity large-scale off-grid causes system frequency to decline, the stability by following two indices evaluating system frequency:
1) in dynamic transition process, low-limit frequency drops to and is less than 49Hz, loses load to avoid the action of electrical network low frequency load shedding equipment;
2) steady frequency after dynamic transition is greater than 49.5Hz and is less than 50.5Hz.
In described step 4, if the voltage of power supply point is U
1∠ 0 °, through impedance Z
lthe circuit of ∠ θ, powers to the load that power is P+jQ, and at this moment the voltage of load side is U
2∠ δ
2; Output power equation is expressed as:
Cancellation δ
2, can obtain:
If the voltage of given power supply point and the voltage of load side, then formula (4) represent P ?on Q coordinate system with
for the center of circle, with
for the circle of radius; Wherein P represents vertical axis, and Q represents trunnion axis, with the power of load absorption be on the occasion of;
If the voltage of load side is parameter, then obtain bunch circle by formula (4), each circle represents the relation of P and Q under the condition of the voltage of given load side; The common tangent line representative of bunch circle allows the extreme boundary of the operational mode existed, and be the operational mode that impossible exist in the upside of this tangent line, the downside of tangent line is the region that can run;
The active power causing near region ultra-high-tension power transmission line to be sent when the quick off-grid of Wind turbines sharply reduces, therefore reduced fast by the meritorious circuit reactive loss brought of transmission, and it is idle approximate constant to charge, then after off-grid, the idle of near region ultra-high-tension power transmission line injected system will increase, and Wind turbines off-grid capacity is larger, the amplitude of increase that injected system is idle is also larger, wind power base near region substation bus bar voltage magnitude rises fast, easily exceed the maximum of apparatus insulated requirement, the risk of insulation breakdown occurs.
Compared with prior art, beneficial effect of the present invention is:
1. practical, better effect is played to prevention and control wind-powered electricity generation off-grid, lifting power grid security;
2. can the scene of the extensive off-grid of wind-powered electricity generation after simulate fault, meanwhile, more outstanding disturbance is on the impact of bulk power grid safe and stable operation;
3. due to the present invention be based on bulk power grid PSD ?the associated analog that carries out of BPA emulation platform, comparatively accurate on the impact of electrical network after therefore simulating wind-powered electricity generation off-grid;
4. from electrical network merit angle, frequency and voltage etc., each runs the risk of the extensive off-grid of side assessment wind-powered electricity generation, and assessment is comparatively comprehensive, quantification.
Accompanying drawing explanation
Fig. 1 is the network operation risk assessment method flow chart of wind electricity large-scale off-grid;
Fig. 2 is one machine infinity bus system figure in the embodiment of the present invention;
Fig. 3 is Infinite bus power system generator's power and angle characteristic schematic diagram in the embodiment of the present invention;
Fig. 4 is electric power system schematic diagram in the embodiment of the present invention;
Fig. 5 is circuit element power and voltage relationship schematic diagram in the embodiment of the present invention;
Fig. 6 is that in the embodiment of the present invention, Jiuquan wind power base is grid-connected and send schematic diagram;
Fig. 7 is Jiuquan wind power integration northwest net main cross sections Power Exchange schematic diagram under targeted manner year large load method in the embodiment of the present invention;
Fig. 8 is Jiuquan ~ merit angle, circuit N ?1 fault power plant, west of a river schematic diagram under target year large load method in the embodiment of the present invention;
Fig. 9 is Hami ~ Dunhuang line power schematic diagram during Jiuquan ~ west of a river circuit N ?1 fault under target year large load method in the embodiment of the present invention;
Figure 10 is wind-powered electricity generation off-grid 3300MW system frequency change curve under target year large load method in the embodiment of the present invention;
Figure 11 is in the embodiment of the present invention under target year large load method, blower fan off-grid 530MW, west of a river passage each 750kV substation bus bar voltage change curve schematic diagram;
Figure 12 is in the embodiment of the present invention under target year large load method, blower fan off-grid 956MW, passage 750kV Dunhuang, west of a river power station busbar voltage dynamic change schematic diagram.
Embodiment
Below in conjunction with accompanying drawing, the present invention is described in further detail.
Due to China's Wind Power Development excessive velocities, and wind-powered electricity generation planning construction and Electric Power Network Planning, blower fan manufacture, Grid-connection standards, construction quality etc. is inharmonious, under large-scale wind power concentrates access high pressure to send scene of dissolving at a distance outside, very easily there is the extensive off-grid of Wind turbines because disturbance causes, and then impact bulk power grid safety.The present invention is directed to this problem, propose a kind of network operation risk assessment method for wind electricity large-scale off-grid, quantize the risk that the extensive off-grid of wind-powered electricity generation brings from each side of operation of power networks, and then play the effect of prevention and control wind-powered electricity generation off-grid, lifting power grid security.Before proposition the present invention, in conjunction with the extensive evolutionary process of off-grid accident of wind-powered electricity generation and the demand of security and stability analysis of large power grid of actual generation, 3 rational supposed premise conditions are proposed:
1) because the evolutionary process such as cause, development of the extensive off-grid of wind-powered electricity generation and Wind turbines initial condition, Wind turbines dynamic characteristic etc. are closely related, it is different that wind energy turbine set each typhoon group of motors affects initial condition by wind speed etc.; And Wind turbines dynamic characteristic one is relevant with initial condition, initial condition is indefinite, and dynamically performance also respectively has difference; Two is relevant with the machine unit characteristic of Wind turbines producer, physical model etc., and wind field blower fan is generally by multiple manufacturer production, and the characteristic of each producer unit differs, and therefore, it is very difficult for reappearing this process;
2) what stress due to the present invention is the final impact of wind electricity large-scale off-grid on bulk power grid safety and stability, therefore more concerned bulk power grid safety and stability problem, and the Detailed simulation of the chain off-grid sequential of blower fan is not as emphasis;
3) due to the importance of bulk power grid security and stability; so all take relatively conservative thinking in the arrangement of bulk power grid actual operating and control strategy are formulated; namely certain margin of safety is left; therefore; the present invention simulates wind electricity large-scale off-grid scene and takes partially serious mode: in general; namely electric network fault occur after through of short duration time delay, the quick off-grid of Wind turbines, to specifying number of units and designated capabilities, assesses bulk power grid safety under this scene.Be assumed to be with this network operation risk assessment method that precondition proposes wind electricity large-scale off-grid provided by the invention, as Fig. 1, the method comprises the following steps:
Step 1: simulated failure causes the accident scene of wind electricity large-scale off-grid;
Step 2: the risk assessment carrying out Power Network Transient Stability after disturbance;
Step 3: the risk assessment carrying out system frequency stability after disturbance;
Step 4: the risk assessment carrying out voltage stability after disturbance.
Described step 1 comprises the following steps:
Step 1 ?1: based on bulk power grid PSD ?BPA emulation platform set up bulk power grid Static Power Flow computation model and bulk power grid multilayer output feedback network model;
Step 1 ?2: simulating grid fault causes the disturbance of wind electricity large-scale off-grid.
Described step 1 ?in 1, bulk power grid Static Power Flow computation model comprises generator model, load model, transformer model and circuit model; Bulk power grid multilayer output feedback network model comprises the generator transient Model based on generator dynamic element, described generator transient Model comprises twin shaft (d, q) model, excitation model, power system stabilizer, PSS model (power system stabilizer, PSS), governor model and prime mover model.
Described step 1 ?2 to comprise the following steps:
1) the electric component place of simulation wind energy turbine set, bulk power grid causes the fault of wind-powered electricity generation off-grid, comprises symmetrical short-circuit fault, asymmetry short circuit fault and disconnection fault;
2) there is rear relaying protection regular event in simulated failure, excision fault element, and the scene of wind-powered electricity generation off-grid occurs after postponing blink;
3) Wind turbines is simulated according to designated capabilities, the scene of specifying number of units scale off-grid.
In described step 2; because the large-scale wind power base of concentrated access is mostly away from load center; wind-powered electricity generation is sent outside at a distance by ultra-high-tension power transmission line; wind power base near region capacity of short circuit is relatively little, grid structure is relatively weak; anti-transient disturbance ability is more weak; need emphasis to assess electrical network main road fault to occur and Power Network Transient Stability subsequently under wind electricity large-scale off-grid dual-impingement, its instability forms comprises merit angle step-out aperiodic and vibration step-out.
As Fig. 2 and Fig. 3, system is equivalent to one machine infinity bus system, if establish original machine power P
m, generator internal e.m.f. E and Infinite bus system voltage U ' be constant, ignore line resistance and distributed capacitance, total apparent reactance of system is X
Σ;
Minor interference is stood and linearisation near working point for Infinite bus system, then has Incremental Equation:
Wherein, δ is generator amature angle; δ
0for the generator amature angle at steady operation point place; P
mfor original machine power; P
efor Generator end electromagnetic power; M is inertia time constant; ω is generator speed; K is synchronising torque coefficient, and
Can obtain system features equation by formula (1) is
Mp
2+K＝0 (2)
Equation (2) is had:
1) if K>0, then characteristic root is
ω
nfor generator amature during system undamped is relative to the natural frequency of oscillation of Infinite bus system, when taking into account mechanical damping, system stability;
2) if K<0, then
characteristic root has a positive real root, and system is unstable, and its instability forms is aperiodicity step-out;
3) if K=0, be then zero repeated root, system is positioned at critical condition, and real system does not allow to run in critical condition;
Physical interpretation can be made according to load angle characteristic to this as follows, if systematic steady state operates in A point, have at that point: P
m=P
e, A point generator amature angle δ
a<90 °, and have
then when system has small sample perturbations to make rotor angle have a fractional increments known Δ δ >0, by
known Generator end electromagnetic power P
efractional increments Δ P will be had
e>0, and P
m=0, thus have equation of rotor motion known, this Δ P
erotor will be caused to slow down, thus Δ δ is reduced, and be tending towards returning former operating condition, after therefore disturbance disappears, system, under damping action, through a transient process, will get back to δ
arun; Therefore system is statically stable in the operation of A point.
If but system initial launch is at B point, P at that point
m=P
e, B point generator amature angle δ
b<90 °, and have
then when system has small sample perturbations, when making rotor angle have a fractional increments, by
known, Generator end electromagnetic power P
efractional increments Δ P will be had
e<0, and P
m=0, thus have equation of rotor motion known, this Δ P
erotor will be caused to accelerate, thus Δ δ is increased further, generator is tending towards step-out, therefore system cloud gray model is unstable at B point.
When system cloud gray model is at C point, now C point generator amature angle δ
c>90 °,
system is in critical condition.Now Generator end electromagnetic power P
ereach maximum, if increase mechanical output again, then because
generator amature angle δ will speed up and be tending towards infinitely great, system step-out.
To Study of Power System Small Disturbance stability analysis, system when supposing normal operation is at t=t
0moment is interfered, and the running status of system is transferred to Δ x (t in this moment by 0
0).This value is the initial condition of the rear system freewheels of interference disappearance.Because interference is enough little, Δ x (t
0) be in the enough little neighborhood of Δ x=0.Therefore the small interference stability problem of nonlinear power system can be studied according to Liapunov linearized theory.Liapunov linearization technique is relevant with the local stability of non linear system, says intuitively, should have similar characteristic when non linear system is moved among a small circle to its linearisation.
State equation and the power flow equation of each dynamic element of electric power system are expressed as:
Wherein, x
ifor the state variable of dynamic element, U is the terminal voltage of dynamic element, i
ifor the electric current of injection network, f
d(x
i, U) and be the function of state of dynamic element; g
d(x
i, U) and be the trend function of dynamic element;
The Linearized state equations of each dynamic element can be expressed as:
Wherein, A
i, B
i, C
iand Y
ibe respectively equation coefficient; B
iand Y
iin value, except the element non-zero corresponding to dynamic element terminal voltage or be used for controlling far-end voltage, other are all zero.Network represents with admittance battle array, Δ i=Y
nΔ U, Δ i are dynamic elements to the Injection Current vector of network, and except to the bus being connected to dynamic element, other are all zero, Y
nfor node admittance matrix;
Can be obtained fom the above equation: Δ x
i=(A
i+ B
i(Y
n+ Y
i)
-1c
i) Δ x=A Δ x.
Order | λ I-A|=0, this formula is called the characteristic equation of matrix A, and wherein I is unit matrix.Meeting | the value of the λ of λ I-A|=0 is called the characteristic value of A matrix, and according to Lyapunov stability first theorem, the stable among a small circle of linear system is what to be determined by the root of linearisation characteristic equation, is specially:
If the system asymptotically stability l) after linearisation, namely when the real part of all characteristic values of matrix A is negative, so actual non linear system is at balance point asymptotically stability;
2) if the system after linearisation is unstable, namely when all characteristic values of matrix A have at least a real part to be just, so actual non linear system is unstable at balance point;
3) if the system neutrality after linearisation, be namely positive without real part in all characteristic values of matrix A, but have at least a real part to be the characteristic value of zero, to the non linear system of reality in balance point neutrality.For electric power system, this situation is also classified as system instability.
As through assessment, after disturbance, system keeps transient stability, then in a period of time yardstick after, electrical network experiences the dynamic transition of another kind of form, at this moment more concerned Wind turbines off-grid on the impact of system response and busbar voltage characteristic.
In described step 3, after Wind turbines scale off-grid, system power generation vacancy, vacancy power is redistributed at each generator according to the synchronizing power coefficient of each generator and moment of inertia, generator electromagnetic power changes, because inertia time constant is larger, in this time scale, the mechanical output of unit prime mover remains unchanged, the imbalance of generator electromagnetic power and mechanical output makes generator speed change, when generator speed change and when entering into the mean speed of system, Generator Governor starts to respond rotation speed change, and change exerting oneself of unit further by its characteristic, take into account the functions combination effect of load simultaneously, finally by the comprehensive power frequency characteristic decision systems frequency of system,
Under electric power system normal operation, once there is load disturbance, assuming that the idle component of load disturbance amount is very little, node voltage amplitude can be used as invariable.The real component of load disturbance amount changes making the voltage phase angle of disturbance point, and load disturbance amount is delivered to all generating sets in system by the change of this phase angle.
If system has m platform generator, there occurs load disturbance amount Δ P at node k place
l, under action of small disturbance, to the electromagnetic power linearisation that i-th generator exports, have
Wherein: P
eiit is the electromagnetic power that i-th generator exports; δ
ij0for two phase difference of node voltage of i, j before disturbance; δ
ik0for two phase difference of node voltage of i, k before disturbance; E '
iwith E '
jbe respectively i-th, constant potential after the reactance of j platform generator transient state; V
kfor the voltage of disturbance point; B
ijfor the internodal transfer susceptance of i, k two; B
ikfor the internodal transfer susceptance of i, k two; P
sijand P
sikbe synchronizing power coefficient.
In disturbance, occur moment, the disturbance quantity of load is distributed between generating set by the synchronizing power coefficient of each generating set, and this process completes rapidly.Simultaneously the completing of this process, not by any restriction of pool, namely the transfer of load disturbance amount is not only carried out between generator in the one's respective area of disturbance, also passes through interconnection simultaneously and shifts to adjacent domain.Because now any Region control mode also has little time to play a role, the load disturbance occurred in a certain district system is inevitable to be reflected on interconnection.
After generating set bears disturbance component, the original electromagnetic power of flip-flop exports, and in this moment, due to the relation of machinery inertial, the impossible flip-flop of mechanical output, is still original numerical value, at this moment causes the imbalance of power, the change of rotary speed of generator group must be caused, and have following relation:
Wherein, J
iit is the moment of inertia of i-th generator; ω
iit is the rotating speed of i-th generator; ω
0for reference rotation speed; P
eit () is the electromagnetic power that i-th generator t exports.
During this period, each generating set will be played a leading role by moment of inertia, start to change rotating speed.Due to the difference of the difference of load disturbance point, each generating set synchronizing power coefficient and moment of inertia, each generating set will by respective relevant parameters, and along with effect each other, changes exerting oneself and the distribution of system load flow of unit.Due to the effect of the synchronizing power coefficient of generating set, in change, all generating sets are made to progress into the mean speed of system.When generating set enters mean speed, the change of generating set electromagnetic power is decided by its coefficient of rotary inertia.First load disturbance amount distributes between unit by generating set synchronizing power coefficient, then transfers to and distributing by turbine generator inertia coefficient.In this course, along with the change of rotary speed of generator group, governing system experiences signal, and changes exerting oneself of unit further by its characteristic, finally according to the frequency of comprehensive governor control characteristics decision systems and the exerting oneself of each generating set of system.
Power shortage after wind electricity large-scale off-grid causes system frequency to decline, the stability by following two indices evaluating system frequency:
1) in dynamic transition process, low-limit frequency drops to and is less than 49Hz, loses load to avoid the action of electrical network low frequency load shedding equipment;
2) steady frequency after dynamic transition is greater than 49.5Hz and is less than 50.5Hz.
In described step 4, wind power base near region substation bus bar voltage and near region electric network element reactive power distribution are closely related, wherein, circuit element injected system idle is that circuit reactive loss and line mutual-ground capacitor charge idle algebraical sum, most large-scale wind electricity base electric power is all sent outside at a distance by the circuit of supertension line even more voltage levels, because line voltage distribution higher grade, circuit is longer, and the charging of direct-to-ground capacitance is idle all larger.
Fig. 4 is simple power system schematic diagram, if the voltage of power supply point is U
1∠ 0 °, through impedance Z
lthe circuit of ∠ θ, powers to the load that power is P+jQ, and at this moment the voltage of load side is U
2∠ δ
2; Output power equation is expressed as:
Cancellation δ
2, can obtain:
If the voltage of given power supply point and the voltage of load side, then formula (4) represent P ?on Q coordinate system with
for the center of circle, with
for the circle of radius; Wherein P represents vertical axis, and Q represents trunnion axis, with the power of load absorption be on the occasion of;
If the voltage of load side is parameter, then obtain bunch circle by formula (4), as Fig. 5, each circle represents the relation of P and Q under the condition of the voltage of given load side; The common tangent line representative of bunch circle allows the extreme boundary of the operational mode existed, and be the operational mode that impossible exist in the upside of this tangent line, the downside of tangent line is the region that can run;
The active power causing near region ultra-high-tension power transmission line to be sent when the quick off-grid of Wind turbines sharply reduces, therefore reduced fast by the meritorious circuit reactive loss brought of transmission, and it is idle approximate constant to charge, then after off-grid, the idle of near region ultra-high-tension power transmission line injected system will increase, and Wind turbines off-grid capacity is larger, the amplitude of increase that injected system is idle is also larger, wind power base near region substation bus bar voltage magnitude rises fast, easily exceed the maximum of apparatus insulated requirement, the risk of insulation breakdown occurs.
Embodiment
For Northwest Grid targeted manner year, based on PSD ?BPA emulation platform, the operation risk of analysis and evaluation Jiuquan wind power base extensive blower fan off-grid Northwest Grid.
As Fig. 6, Jiuquan wind power base comprises Gan Qiaowan, Gan Qiaobei, Gan Qiaodong, Gan Gandong, Gan Ganbei, Gan Ganxi etc. by the grid-connected main force's wind energy turbine set of 330kV circuit, goal in research year Jiuquan wind power base installed capacity in the present invention is about 5,000,000 kilowatts, each wind energy turbine set is grid-connected by 0.69/35/330kV electric pressure, on send power and send through the honest bright ?wine spring ?river western ?Wusheng 750kV passway for transmitting electricity (west of a river passway for transmitting electricity) of nearly thousand kilometers.
(1) wind-powered electricity generation off-grid transient stability operation risk assessment;
Fig. 7 is targeted manner year Northwest Grid Jiuquan wind power base actual power power, northwest each province discontinuity surface transmission power situation schematic diagram, and wind-powered electricity generation actual exerting oneself in Jiuquan is about 2900MW, and Xinjiang send Gansu, northwest section power to be 1000MW.
When west of a river passway for transmitting electricity Jiu Quan ?the permanent N of west of a river double loop generation three-phase ?1 short trouble, Wind turbines is whole off-grid after system jam, system active power vacancy is larger, system frequency declines, the meritorious raising of exerting oneself of the whole network unit under speed regulator effect, Xinjiang Power northwestwards electrical network power transmission power increase, Xinjiang Power maintenance level is declined, causes major network merit angle, Xinjiang unit relative northwest unstability.From emulation, under this target year large load method, when Jiuquan wind power base wind-powered electricity generation off-grid scale reaches about 2900MW, easily there is transient state merit angle unstability risk.Result of calculation list is as shown in table 1.Simulation result as shown in Figure 8 and Figure 9.
Table 1
(2) wind-powered electricity generation off-grid frequency operation risk assessment;
The spinning reserve capacity of system has great impact to the system response after extensive chaser, according to operating standard, should leave when electrical network normally runs 2% ?5% spinning reserve capacity.The present invention considers relatively serious situation, consider simultaneously Xi Bei ?Xinjiang Power likely separate network operation after a failure, then under target year large load method, Northwest Grid (not containing Xinjiang) spinning reserve should exceed the maximum unit capacity of separate unit in net, i.e. 1000MW, therefore in this research mode, Northwest Grid (not containing Xinjiang) leaves spinning reserve 1120MW, is about 2.37% of maximum generation capacity, adds up to spinning reserve to be about 2.36% of the rear system of Xinjiang, northwest networking;
Wind power base Wind turbines actual power that sends in Jiuquan is about 3300MW, and the whole instantaneous off-grid of Jiuquan wind power base 3300MW online wind-powered electricity generation after consideration disturbance, system frequency change as shown in Figure 10.From simulation result: when wind-powered electricity generation off-grid scale reaches 3300MW, system frequency deviation is close to 1Hz, and system frequency is close to UFLS operating value 49Hz.
Therefore, under target year large load method, when disturbance causes Jiuquan wind-powered electricity generation off-grid scale more than 3300MW, system easy occurrence frequency unstability risk.
(3) wind-powered electricity generation off-grid voltage operation risk assessment;
Under target year large load method, Jiuquan wind power output 2900MW, northwest 1000MW is sent in Xinjiang.Under basal profile, 750kV passage each main substation bus bar voltage levvl in the west of a river is specifically as shown in table 2, and Biao Zhong unit is kV.As seen from the table, voltage levvl all in the reasonable scope.
Table 2
| Hami 750kV | Dunhuang 750/330kV | Jiuquan 750/330kV | West of a river 750/330kV | Wusheng 750/330kV |
| 774.2 | 771.2/356.8 | 766.1/361.2 | 760.5/350.6 | 763.5/348.3 |
| The western wind-electricity integration station of bridge | Yumen 330kV | The Jiayu Pass 330kV | Zhangye 330kV | Liangzhou 330kV |
| 357.1 | 361.4 | 360.4 | 356.2 | 348.5 |
Because certain disturbance occurs wind energy turbine set, when causing Jiuquan blower fan (mainly area, Guazhou County) off-grid 530MW, the dynamic change of west of a river passway for transmitting electricity main 750kV substation bus bar voltage as shown in figure 11.
Jiuquan blower fan (mainly area, Guazhou County) off-grid capacity continues to strengthen, and when off-grid fan capacity reaches 956MW, the 750kV Dunhuang busbar voltage change curve of west of a river passage as shown in figure 12.
The voltage climbs schematic diagram of 530MW, 956MW after comparison blower fan off-grid, can find out the increasing along with wind-powered electricity generation off-grid capacity, the amplitude of voltage climbs strengthens, when after blower fan off-grid capacity 956MW, Dunhuang busbar voltage has exceeded perunit value 1, and namely the famous value of voltage is greater than safe voltage 800kV.
Therefore, under target year large load method, when disturbance causes Jiuquan wind-powered electricity generation off-grid scale more than 956MW, easily there is voltage climbs risk in wind-electricity integration near region busbar voltage, has influence on the insulation safety of grid equipment element.
Finally should be noted that: above embodiment is only in order to illustrate that technical scheme of the present invention is not intended to limit, although with reference to above-described embodiment to invention has been detailed description, those of ordinary skill in the field are to be understood that: still can modify to the specific embodiment of the present invention or equivalent replacement, and not departing from any amendment of spirit and scope of the invention or equivalent replacement, it all should be encompassed in the middle of right of the present invention.
Claims (6)
1. a network operation risk assessment method for wind electricity large-scale off-grid, is characterized in that: said method comprising the steps of:
Step 1: simulated failure causes the accident scene of wind electricity large-scale off-grid;
Step 2: the risk assessment carrying out Power Network Transient Stability after disturbance;
Step 3: the risk assessment carrying out system frequency stability after disturbance;
Step 4: the risk assessment carrying out voltage stability after disturbance;
In described step 2, the Power Network Transient Stability under the fault generation of assessment electrical network main road and subsequently wind electricity large-scale off-grid dual-impingement, its instability forms comprises merit angle step-out aperiodic and vibration step-out;
System is equivalent to one machine infinity bus system, if establish original machine power P
m, generator internal e.m.f. E and Infinite bus system voltage U ' be constant, ignore line resistance and distributed capacitance, total apparent reactance of system is X
Σ;
Minor interference is stood and linearisation near working point for Infinite bus system, then has Incremental Equation:
Wherein, δ is generator amature angle; δ
0for the generator amature angle at steady operation point place; P
mfor original machine power; P
efor Generator end electromagnetic power; M is inertia time constant; ω is generator speed; K is synchronising torque coefficient, and
Can obtain system features equation by formula (1) is
Mp
2+K＝0 (2)
Equation (2) is had:
1) if K>0, then characteristic root is
ω
nfor generator amature during system undamped is relative to the natural frequency of oscillation of Infinite bus system, when taking into account mechanical damping, system stability;
2) if K<0, then
characteristic root has a positive real root, and system is unstable, and its instability forms is aperiodicity step-out;
3) if K=0, be then zero repeated root, system is positioned at critical condition, and real system does not allow to run in critical condition.
2. the network operation risk assessment method of wind electricity large-scale off-grid according to claim 1, is characterized in that: described step 1 comprises the following steps:
Step 1 ?1: based on bulk power grid PSD ?BPA emulation platform set up bulk power grid Static Power Flow computation model and bulk power grid multilayer output feedback network model;
Step 1 ?2: simulating grid fault causes the disturbance of wind electricity large-scale off-grid.
3. the network operation risk assessment method of wind electricity large-scale off-grid according to claim 2, is characterized in that: described step 1 ?in 1, bulk power grid Static Power Flow computation model comprises generator model, load model, transformer model and circuit model; Bulk power grid multilayer output feedback network model comprises the generator transient Model based on generator dynamic element, and described generator transient Model comprises twin shaft model, excitation model, power system stabilizer, PSS model, governor model and prime mover model.
4. the network operation risk assessment method of wind electricity large-scale off-grid according to claim 2, is characterized in that: described step 1 ?2 to comprise the following steps:
1) the electric component place of simulation wind energy turbine set, bulk power grid causes the fault of wind-powered electricity generation off-grid, comprises symmetrical short-circuit fault, asymmetry short circuit fault and disconnection fault;
2) there is rear relaying protection regular event in simulated failure, excision fault element, and the scene of wind-powered electricity generation off-grid occurs after postponing blink;
3) Wind turbines is simulated according to designated capabilities, the scene of specifying number of units scale off-grid.
5. the network operation risk assessment method of wind electricity large-scale off-grid according to claim 1, it is characterized in that: in described step 3, after Wind turbines scale off-grid, system power generation vacancy, vacancy power is redistributed at each generator according to the synchronizing power coefficient of each generator and moment of inertia, generator electromagnetic power changes, because inertia time constant is larger, in this time scale, the mechanical output of unit prime mover remains unchanged, the imbalance of generator electromagnetic power and mechanical output makes generator speed change, when generator speed change and when entering into the mean speed of system, Generator Governor starts to respond rotation speed change, and change exerting oneself of unit further by its characteristic, take into account the functions combination effect of load simultaneously, finally by the comprehensive power frequency characteristic decision systems frequency of system,
Power shortage after wind electricity large-scale off-grid causes system frequency to decline, the stability by following two indices evaluating system frequency:
1) in dynamic transition process, low-limit frequency drops to and is less than 49Hz, loses load to avoid the action of electrical network low frequency load shedding equipment;
2) steady frequency after dynamic transition is greater than 49.5Hz and is less than 50.5Hz.
6. the network operation risk assessment method of wind electricity large-scale off-grid according to claim 1, is characterized in that: in described step 4, if the voltage of power supply point is U
1∠ 0 °, through impedance Z
lthe circuit of ∠ θ, powers to the load that power is P+jQ, and at this moment the voltage of load side is U
2∠ δ
2; Output power equation is expressed as:
Cancellation δ
2, can obtain:
If the voltage of given power supply point and the voltage of load side, then formula (4) represent P ?on Q coordinate system with
for the center of circle, with
for the circle of radius; Wherein P represents vertical axis, and Q represents trunnion axis, with the power of load absorption be on the occasion of;
If the voltage of load side is parameter, then obtain bunch circle by formula (4), each circle represents the relation of P and Q under the condition of the voltage of given load side; The common tangent line representative of bunch circle allows the extreme boundary of the operational mode existed, and be the operational mode that impossible exist in the upside of this tangent line, the downside of tangent line is the region that can run;
The active power causing near region ultra-high-tension power transmission line to be sent when the quick off-grid of Wind turbines reduces, therefore reduced by the meritorious circuit reactive loss brought of transmission, and it is idle constant to charge, then after off-grid, the idle of near region ultra-high-tension power transmission line injected system will increase, and Wind turbines off-grid capacity is larger, the amplitude of increase that injected system is idle is also larger, and wind power base near region substation bus bar voltage magnitude rises, exceed the maximum of apparatus insulated requirement, the risk of insulation breakdown occurs.
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| CN103729557B (en) * | 2013-12-25 | 2016-10-05 | 大连理工大学 | Static N-X batch processing method based on PSD-BPA |
| CN104901330B (en) * | 2014-03-04 | 2017-05-10 | 国家电网公司 | Comprehensive design method for preventing high-voltage grid disconnection of wind power plant |
| CN103956742B (en) * | 2014-04-14 | 2015-12-02 | 国家电网公司 | The defining method of power system operation mode under a kind of complicated energy environment |
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| CN104156614B (en) * | 2014-08-25 | 2017-09-01 | 国家电网公司 | A kind of Study of Risk Evaluation Analysis for Power System method based on Steady State Security Region |
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| CN105354761B (en) * | 2015-11-02 | 2020-03-20 | 山东大学 | Safety and efficiency evaluation method and system for accessing wind power into power grid |
| CN106786788B (en) * | 2015-11-20 | 2019-07-19 | 中国电力科学研究院 | A kind of power grid wind submitting capability assessment method counted and wind power plant off-grid constrains |
| CN105490263B (en) * | 2015-11-24 | 2017-12-29 | 国家电网公司 | The method and system of the small probability of interference stability analysis of wind power integration power system |
| CN106202729A (en) * | 2016-07-12 | 2016-12-07 | 中国石油化工股份有限公司 | A kind of transient characterisitics evaluation methodology of refining and petrochemical processing units electric power system |
| CN106451528B (en) * | 2016-08-03 | 2019-01-25 | 国电南瑞科技股份有限公司 | A kind of large-scale wind power off-grid control method of comprehensive FACTS and HVDC coordination optimization |
| CN106549389B (en) * | 2016-11-10 | 2022-04-29 | 中国电力科学研究院 | Amplitude limiting parameter optimization method for direct-current minimum trigger angle limiter |
| CN108512219B (en) * | 2018-03-14 | 2020-08-28 | 国家电网公司华中分部 | Method for evaluating power receiving capacity of multi-channel receiving end system under voltage stability constraint |
| CN109088413B (en) * | 2018-08-02 | 2022-12-30 | 清华大学 | Dynamic reactive power planning and site selection method and device for direct-current receiving-end power grid |
| CN111276980B (en) * | 2018-12-04 | 2021-07-13 | 国网冀北电力有限公司电力科学研究院 | Method, device and equipment for predicting high-voltage interlocking offline risk |
| CN110943451B (en) * | 2019-12-12 | 2021-05-25 | 华北电力大学 | System partition area inertia evaluation method based on disturbance data |
| CN111444596B (en) * | 2020-03-12 | 2023-07-18 | 国家电网公司东北分部 | Method and device for detecting frequency safety after power disturbance of power system |
| CN112101793B (en) * | 2020-09-16 | 2022-07-01 | 国电南瑞南京控制***有限公司 | Safety and stability risk quantitative evaluation method considering new energy uncertainty |
| CN113449968B (en) * | 2021-06-09 | 2023-08-29 | 重庆锦禹云能源科技有限公司 | New energy power grid frequency risk assessment method and device based on deep learning |
| CN117057618B (en) * | 2023-10-11 | 2024-01-30 | 成都大公博创信息技术有限公司 | Regional electromagnetic security risk assessment method, system, equipment and medium |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
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-
2013
- 2013-05-09 CN CN201310169659.5A patent/CN103337855B/en active Active
Non-Patent Citations (3)
| Title |
|---|
| 基于PSD—BPA的电网潮流稳定计算分析平台开发与应用;罗彬等;《电力***自动化》;20120910;第36卷(第17期);第119-123页 * |
| 大规模风电机组连锁脱网仿真分析及对策;杨帆等;《电力科学与工程》;20130131;第29卷(第1期);第21-26页 * |
| 风电在线风险评估***的开发及应用;苏峰等;《电力***保护与控制》;20120816;第40卷(第16期);第130-135页 * |
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