CN103279639A - Receiving-end network voltage stabilization overall process situation assessment and prevention and control method based on responses - Google Patents

Abstract

The invention provides a receiving-end network voltage stabilization overall process situation assessment and prevention and control method based on responses. The method comprises the steps of S1, obtaining various off-line simulation data or real-time measuring data; S2, constructing equivalent power transmission models of nodes according to node practical transfer power; S3, obtaining a node quiescent voltage stability margin index Vsi of equivalent power transmission model parameters of each node; S4, constructing a node reactive compensation assessment index according to the equivalent power transmission model parameters of each node; S5, setting an early warning threshold value Ncr of the node quiescent voltage stability margin index, and calculating a load shedding estimation of a weaker node when the quiescent voltage stability margin index Vsi of each node is smaller than the Ncr. According to the receiving-end network voltage stabilization overall process situation assessment and prevention and control method based on the responses, a weak node or a weak area in a current operating mode can be found out, a rapid estimation of reactive compensation levels and load shedding of each node is achieved, and the method can be widely applied to the fields of power network planning and online security monitoring.

Description

Stablize the assessment of overall process situation and preventing control method based on the receiving end line voltage of response

Technical field

The present invention relates to the assessment of receiving end line voltage stability and safety and aid decision making field of various grid simulations or measurement data, be specifically related to a kind of receiving end line voltage based on response and stablize the assessment of overall process situation and preventing control method.

Background technology

Deepening continuously of the continuous expansion of the interconnected scope of electrical network, power industry marketization system reform, and extra-high voltage alternating current-direct current is transmitted electricity, the lasting access of renewable energy power generation, increased the uncertain and intermittent of operation of power networks, make that operation of power networks environment probability complicated day by day, that disturbance takes place is bigger and it is wider to involve, the power network safety operation under the running environment and overall process prevention and control are had higher requirement.

Macroscopic view, electrical network be divided into make a start, power transmission network and receiving end 3 parts.Broad sense receiving end electrical network mainly centered by the load area of concentration, links to each other by peripheral interconnection and the remote broad sense power supply of making a start, and then the equilibrium of supply and demand of realization electric energy.Along with the fast development of society, economy and power industry, the swift and violent increase of receiving-end system scale and its complexity are got over complicated.Because not matching of the energy and load center areal distribution, and consider factor restriction such as environment, receiving-end system internal electric source underbraced, a large amount of electric energy need carry out long-distance transmissions from a distant place.

Since the eighties in 20th century, lasting on the low side, the collapse of voltage event of a lot of voltages takes place in a plurality of large-scale power systems in succession in the world, cause large tracts of land, long power failure, cause enormous economic loss and social influence, make the stable focus that becomes the concern of International Power educational circles gradually of voltage.The voltage stable problem comprises that mainly static voltage stability and dynamic electric voltage are stable, divides from the time, and the dynamic electric voltage stable problem can be divided into the stable and medium-term and long-term voltage of transient voltage and stablize.

Current, the emphasis of the stable research of voltage mainly comprises process, mechanism, index and the influence factor that the voltage stability problem takes place, comprising concrete mathematical modeling, analysis and computing method, and developed multiple voltage stability Calculation, analysis tool and prevented automatic control system of collapse of voltage etc.For the static voltage stability problem, have many received computing method at present, as the many solutions of trend, continuous tide method, nearest collapse of voltage point method etc.And people are deep not enough to the research of dynamic electric voltage stability analysis, and especially the time frame that involves of dynamic electric voltage stable problem is long, is difficult to they are carried out unified analysis.Transient voltage mathematical model stable and that the transient state angle stability adopts is more approaching, can adopt traditional time-domain-simulation method to analyze.And the normally used method of medium-term and long-term voltage stability simulation be in the time-domain-simulation program, add with mid-term voltage stablize relevant component models.

The voltage of modeling Network Based and numerical evaluation is stablized advantages such as relevant simulating analysis has intuitively, abundant information, is that existing power grid security analysis is checked important instrument with strategy, also is the main foundation that dispatching of power netwoks department instructs Operation of Electric Systems.As seen, the confidence level of electric system simulation analysis result is directly connected to the safety and economic operation of system.At present, be used for the numerical algorithm comparative maturity of power system steady state voltage stability and dynamic electric voltage stability simulation, cause that the inaccurate reason of emulation mainly is the inaccurate of component models and parameter in the system.The accident of having a power failure on a large scale the several times post-simulation that takes place is found in recent years, uses existing simulation data base can not reappear the real system unstability, and there are a lot of problems in the accuracy of emulation.Based on the analytical approach of mathematical modeling and emulation, be subjected to the restriction of factors such as electric network model, parameter and numerical evaluation, be difficult to adapt to the requirement that voltage is stablized real-time prevention and control at aspects such as application scale, speed and reliabilities.Voltage security defense mode based on " off-line decision-making; online coupling " can not be mated the electrical network real working condition fully, and be subjected to the influence of model and parameter, the gained scheme is too conservative (or optimistic) sometimes, and especially shot array problem has seriously limited the quantity that may consider operating mode.Therefore, electrical network needs off-line and online comprehensive safety assessment and the system of defense that combines.Development of technology such as computing machine, communication, network, (Wide Area Measurement System WAMS) economizes accent in a plurality of nets mediations and comes into operation, for the operation of power networks situation quantitative evaluation under the real time environment brings new opportunity to make WAMS.

From the dynamic recovery characteristics of physics and external presentation, the voltage stable problem mainly focuses on the receiving end electrical network, has certain local characteristics, and voltage unstability (or collapse) is often in electrical network static state (metastable state), transient state or medium-term and long-term overall process.Yet up to the present, the stable static state of ripe voltage, transient state and medium-term and long-term analytical approach and software all have stronger independence at particular problem.Equally, the stabilization of power grids analysis based on the WAMS system mainly focuses on two aspects with control: a transient state angle stability that is based on actual measurement track is estimated; Two are based on the static voltage stability assessment and control of Dai Weinan equivalence method.Use and almost do not have and stablize the research of rapid evaluation and adaptive control aspect and engineering based on the transient voltage of WAMS system.

In the face of current power network development general layout, voltage stable problem at different conditions and scene, run through and utilize existing ripe analytical algorithm and software, in conjunction with ripe WAMS system platform, further investigate the assessment of big receiving end electrical network overall process voltage critical sequences, decision-making and Data Fusion mechanism comprehensively, explore and research and development off-line simulation and the efficient process module Intellectualized starting that combines at line tracking and mutual method of calibration, set up based on the comprehensive safety on line of the receiving end line voltage overall process of multiple information sources and check and real-time system of defense system.

Summary of the invention

For this reason, the invention provides a kind of receiving end electrical network overall process voltage based on the multiple response information source and stablize situation assessment and preventing control method, this method can be at the multiple off-line simulation of electrical network or real-time measuring data, realize that the voltage under the different running statuses stablizes overall process comprehensive assessment, decision-premaking and on-line monitoring and early warning, raising is received greatly terminal voltage voltage security operation level, reduce the collapse of voltage contingency occurrence probability, guarantee the safe and stable operation of China's extra-high voltage grid, all have most important theories and instruct and the engineering practice meaning, this method comprises:

Step S1 obtains various off-line simulation data or real-time measuring data, according to the corresponding scene of the described data obtained respectively unloading be static data formatted file or Temporal Data formatted file;

Described off-line simulation data are transient state fault time-domain-simulation data, the electric network data of described real-time measuring data for measuring in real time by SCADA system, EMS, WAMS, DTS or DCS;

Step S2 adds up the equivalent power P that described node circulates to all electric network elements that arbitrary node connects by meritorious the flow direction _E+ jQ _E, make up the equivalence transmission of electricity model of described node according to described node actual transfer power, in conjunction with node voltage U, adopt the on-line tracing discrimination method to try to achieve the equivalence transmission of electricity model parameter of each described node;

Step S3 tries to achieve node static voltage stability nargin index V according to the described equivalence transmission of electricity model parameter of described each node _Si, according to the static voltage stability nargin index V of described each node _SiValue is determined relative weak node;

Step S4 is according to the described equivalence transmission of electricity model parameter of described each node, in conjunction with the meritorious value of the current circulation of described node P _E, try to achieve virtual active loss under the described node equivalence transmission of electricity model correspondence needed idle amount Q when minimum _Min, make up node reactive-load compensation evaluation index $Q_{\mathrm{ci}}=\left|\frac{Q_E-Q_{\min }}{Q_E}\right|;$

Step S5 sets the early warning sill value N of described node static voltage stability nargin index _Cr, calculate described node static voltage stability nargin index V _SiLess than described early warning sill value N _CrThe cutting load of the relative weak node of Shi Suoshu is estimated.

In first preferred embodiment provided by the invention: among the described step S1, be the flow data formatted file if response data is the data conversion storage of trend section character, if transient state or the dynamic data of time-domain-simulation class, unloading is the time series formatted file;

If response data is the SCADA system data, directly utilizes the later data of SCADA system state estimation to be used as static data and handle.

In second preferred embodiment provided by the invention: among the described step S1,

If the data of obtaining are WAMS data, adopt the method for recursive filtering that PMU measurement time series data is carried out the mean filter processing, the mean value computation formula is

N gets 5 in practical engineering application;

If detecting a certain moment PMU measures with a last moment measured value difference bigger, take off PMU measuring value at a moment again, judge that with this it is that bad data or big disturbance event take place that PMU measures, if judge that it is bad data that PMU measures, using constantly, the PMU measuring value replaces, if judge it is that big disturbance event takes place, start the transient stability quantitative estimation method.

In the 3rd preferred embodiment provided by the invention: the transmission of electricity of equivalence described in described step S2 model parameter comprises equivalent source electromotive force E _E, equivalent branch impedance mould Z _EWith angle of impedance α.

In the 4th preferred embodiment provided by the invention: the described equivalence transmission of electricity model parameter according to described each node among the described step S3 is tried to achieve node static voltage stability nargin index V _SiMethod comprises: find the solution and find the solution according to maximum active power according to modulus of impedance;

According to modulus of impedance solution node static voltage stability nargin index

Wherein, Z _LExpression equivalent load modulus of impedance;

According to maximum active power solution node static voltage stability nargin index

Wherein, P _CrBe the meritorious transport capacity of maximum,

Φ and α are respectively equivalent load power-factor angle and the angle of impedance of node equivalence transmission of electricity model.

In the 5th preferred embodiment provided by the invention: among the described step S3 according to the static voltage stability nargin index V of each node _SiThe value size sorts, and determines relative weak node, realizes the location of relative weak node or weakness zone;

By comparing the V of minimum node under the different modes _SiWeigh each mode voltage degree of stability;

Calculate electrical network averaged static voltage stability margin index N is the grid nodes number.

In the 6th preferred embodiment provided by the invention: it is characterized in that, if the described data of obtaining are transient state fault time-domain-simulation data, computing node static voltage stability nargin index V among the described step S3 _SiMethod is:

When transient state merit angle or transient voltage were all stablized, to merit angle single pendulum reentry point, perhaps minimum voltage fell and a little determines the evaluation time section according to maximal phase; When transient state merit angle unstability or transient voltage unstability, can spend greater than 180 merit angle reentry point according to maximal phase, perhaps minimum voltage falls a little definite evaluation time section;

The data of discontinuity surface are carried out the assessment of static voltage stability situation during in the described evaluation time section each, ask the averaged static voltage stability margin index V of all sections _MsiMean value V _Tmsi, perhaps minimum static voltage stability nargin index V _SiminMean value V _Tsimin, as the voltage stability margin index of described transient state time-domain-simulation data.

In the 7th preferred embodiment provided by the invention: make up node reactive-load compensation evaluation index Q among the step S4 _CiAfter, with the reactive-load compensation evaluation index Q of all nodes of electrical network _CiAverage, try to achieve the average reactive-load compensation vacancy of electrical network index Realize whole reactive-load compensation vacancy proficiency assessment under the current method of operation of electrical network;

Wherein, n represents the number of all nodes of electrical network, Q _CijThe reactive-load compensation evaluation index of representing j node.

In the 8th preferred embodiment provided by the invention: among the step S5, computing node static voltage stability nargin index V _SiLess than early warning sill value N _CrThe time cutting load method estimated be:

According to described node equivalence transmission of electricity model parameter, try to achieve corresponding static voltage stability virtual linear border δ under the described equivalence transmission of electricity model _Cr, described border in the expression formula of power-factor angle and phase angle coordinate space is:

${\mathrm{\δ}}_{\mathrm{cr}}=\left\{\begin{array}{c}-0.5\mathrm{\Φ}+0.5\mathrm{\α}(-\mathrm{\α}\≤\mathrm{\Φ}\≤\mathrm{\π}/2)\\ 0.5\mathrm{\Φ}+1.5\mathrm{\α}(-\mathrm{\π}/2\≤\mathrm{\Φ}\≤-\mathrm{\α})\end{array}\right.$

Wherein, Φ, α are respectively equivalent load power-factor angle and the angle of impedance of node equivalence transmission of electricity model;

(1) constant power factor cutting load amount is:

Meritorious excision amount Δ P ₁:

$\mathrm{\Δ}{P}_1=\frac{{E_E}^2\cos \mathrm{\Φ}\sin ({\mathrm{\δ}}_0-{\mathrm{\δ}}_1+\mathrm{\Φ}-\mathrm{\α})\sin ({\mathrm{\δ}}_1-{\mathrm{\δ}}_0)}{Z_E{\sin }^2(\mathrm{\Φ}-\mathrm{\α})}$

Wherein, δ ₀And δ ₁Be respectively the equivalent merit angle of initial launch point and adjusting back operating point, δ ₁=N _Crδ _Cr,

Idle excision amount Δ Q ₁=Δ P ₁Tan Φ;

(2) minimum cutting load amount:

Equivalence merit angle variable quantity $\mathrm{\Δ\δ}=2\frac{{\mathrm{\δ}}_0-N_{\mathrm{cr}}{\mathrm{\δ}}_{\mathrm{cr}0}}{0.5N_{\mathrm{cr}}+2},$

Equivalent Power Factor angle variable quantity $\mathrm{\Δ\Φ}=\frac{{\mathrm{\δ}}_0-N_{\mathrm{cr}}{\mathrm{\δ}}_{\mathrm{cr}0}}{0.5N_{\mathrm{cr}}+2},$

Be Φ ₁=Φ ₀-ΔΦ, δ ₁=δ ₀-Δ δ, Φ ₀And Φ ₁Be respectively the equivalent load power-factor angle of initial launch point and adjusting back operating point, δ _Cr0Be the corresponding critical phase angular difference of initial launch point;

With Φ ₁And δ ₁Back operating point P is regulated in substitution ₁Computing formula:

$P_1=\frac{{E_E}^2\cos {\mathrm{\Φ}}_1[\cos (2{\mathrm{\δ}}_1+{\mathrm{\Φ}}_1-\mathrm{\α})-\cos ({\mathrm{\Φ}}_1-\mathrm{\α})]}{2Z_E{\sin }^2({\mathrm{\Φ}}_1-\mathrm{\α})}$ After find the solution P ₁,

According to P ₁Find the solution and regulate back operating point Q ₁=P ₁Tan Φ ₁,

Obtain minimum meritorious excision amount Δ P ₁=P ₀-P ₁,

Corresponding idle excision amount Δ Q=Q ₀-Q ₁

In the 9th preferred embodiment provided by the invention: adopt the mode of off-line tasks in parallel to carry out respectively at N-1, N-2, transient state fault collection or medium-term and long-term calculation task and filter out more serious forecast failure, adopt the tasks in parallel pattern to realize that the voltage of the various anticipation methods of operation and fault collection stablize situation and assesses and aid decision making; And N-1 that can static voltage stability is more serious, N-2 fault are utilized transient state or the further verification of medium-term and long-term emulation.

In the tenth preferred embodiment provided by the invention: for the WAMS real-time measuring data, the pattern that adopts online tasks in parallel is carried out voltage to the actual measuring point of PMU and is stablized the situation assessment, and assesses the reactive-load compensation level of each node and the cutting load estimator of low-voltage stabilizing nargin node synchronously;

At different off-lines or online operation of power networks data section, statistics provides the cutting load of static voltage stability nargin index, reactive-load compensation level and the weak node of each node and estimates in advance; At different forecast failure collections, give be out of order order of severity quantizating index and corresponding reactive-load compensation and cutting load aid decision making reference policy, for operation, mode, planning personnel's reference.

The beneficial effect that a kind of receiving end line voltage based on response provided by the invention is stablized the assessment of overall process situation and preventing control method comprises:

1, a kind of receiving end line voltage based on response provided by the invention is stablized the assessment of overall process situation and preventing control method, based on grid responsive (emulation or measurement) data, picks out its equivalence transmission of electricity model parameter according to the true transfer power of each node of electrical network; Try to achieve each node static voltage stability nargin index with each node equivalence transmission of electricity model, each node static voltage stability index is sorted, can find out weak node or weakness zone under this method of operation; Equally, according to each node equivalence transmission of electricity model, can also realize the quick estimation of each node reactive-load compensation level and cutting load amount under the current method of operation; The rapid evaluation efficient of situation is stablized in the pattern raising of employing tasks in parallel to off-line forecast failure collection or on-Line Voltage, realized voltage under real-time power network running status or the forecast failure is stablized the intelligent assessment of situation and aid decision making, had excellent application value and promotion prospect.

2, when the data that obtain are the WAMS data, by adopting the mode of mean filter, bad data and big disturbance anticipation, improve the availability of PMU data, and in time start the transient stability predictor method.

3, follow according to grid nodes actual transfer power and make up this node equivalence two nodes transmission of electricity model, this equivalence model is different from traditional Dai Weinan equivalence method, voltage stability that can all nodes of comprehensive assessment electrical network.

4, at a certain method of operation profile data of electrical network, utilize each node to simplify equivalence transmission of electricity model equivalence transmission power, try to achieve each node static voltage stability nargin index fast, to realize the quick location of electrical network weak node or weakness zone.This equivalent process method is because handle separately at each node, be conducive to realize the tasks in parallel processing, avoided tradition to be subjected to the dependence of electric network model and parameter based on the Jacobian matrix method equally, when electrical network was on a grand scale, classic method computing velocity and precision all were difficult to guarantee.Utilize the static voltage stability nargin index of all nodes of electrical network to try to achieve electrical network average voltage stability margin index, more scientific and rational evaluation different running method or fault collection static voltage stability influence degree.

5, try to achieve electrical network averaged static voltage stability margin index according to each node static voltage stability nargin index, make things convenient for quantitative evaluation different running method or false voltage stability margin situation.

6, in conjunction with node actual fed equivalent power and corresponding equivalent-simplification transmission of electricity model, try to achieve this node at current equivalent model and carry the minimum corresponding idle amount of gained active loss under the meritorious situation, and then the idle amount of comparison present node equivalence conveying is determined the no-power vacancy situation under the current method of operation of this node, only according to electrical network actual operating data, can simply, intuitively weigh whole reactive-load compensation vacancy level under the current method of operation of electrical network.

7, according to node equivalence transmission of electricity model, constructed the static voltage stability linear barrier in power-factor angle and phase angle coordinate space, this border is conducive to intuitively, makes things convenient for online Prediction cutting load direction and amount.By this linear-static voltage stability boundaris, when a certain node static voltage stability nargin index during greater than the early warning sill value of a certain setting, can rapid Estimation go out constant power factor or the minimum cutting load amount of this node correspondence according to the direct algebraic operation of a current running status needs.

Description of drawings

Be illustrated in figure 1 as electrical network arbitrary node representative model synoptic diagram provided by the invention;

Be illustrated in figure 2 as node equivalence transmission of electricity model synoptic diagram provided by the invention;

Be illustrated in figure 3 as virtual reactive-load compensation provided by the invention and network loss and concern synoptic diagram;

Be illustrated in figure 4 as fast cut back provided by the invention and estimate synoptic diagram;

Be illustrated in figure 5 as the voltage based on the multiple response information source provided by the invention and stablize overall process prevention and control structural drawing.

Embodiment

With reference to the accompanying drawings the specific embodiment of the present invention is described in further detail below.

The invention provides a kind of receiving end line voltage based on response and stablize the assessment of overall process situation and preventing control method, comprise the steps:

Step S1 obtains various off-line simulation data or real-time measuring data, according to the corresponding scene of the described data obtained respectively unloading be static data formatted file or Temporal Data formatted file;

Described off-line simulation data are transient state fault time-domain-simulation data, the electric network data of described real-time measuring data for measuring in real time by SCADA system, EMS, WAMS, DTS or DCS;

Step S2 adds up the equivalent power P that described node circulates to all electric network elements that arbitrary node connects by meritorious the flow direction _E+ jQ _E, make up the equivalence transmission of electricity model of described node according to described node actual transfer power, in conjunction with node voltage U, adopt the on-line tracing discrimination method to try to achieve the described equivalence transmission of electricity model parameter of each described node;

Step S3 tries to achieve node static voltage stability nargin index V according to the described equivalence transmission of electricity model parameter of described each node _Si, according to the static voltage stability nargin index V of described each node _SiValue is determined relative weak node;

Step S4 is according to the described equivalence transmission of electricity model parameter of described each node, in conjunction with the meritorious value of the current circulation of described node P _E, try to achieve virtual active loss under the described node equivalence transmission of electricity model correspondence needed idle amount Q when minimum _Min, make up node reactive-load compensation evaluation index $Q_{\mathrm{ci}}=\left|\frac{Q_E-Q_{\min }}{Q_E}\right|;$

Step S5 sets the early warning sill value N of described node static voltage stability nargin index _Cr, calculate described node static voltage stability nargin index V _SiLess than described early warning sill value N _CrThe cutting load of the relative weak node of Shi Suoshu is estimated.

Among the step S1 to off-line simulation data and real-time simulation data, no matter off-line simulation adopts what model, algorithm and electrical network scale, only at the response data of handling static state or transient state, provide quantitative voltage and stablize the situation assessment result, if the data conversion storage of trend section character is native system flow data formatted file, if the data of transient state or dynamic time-domain-simulation one class are the time series formatted file with regard to unloading.Equally, if analyze the SCADA system data, handle with regard to directly utilizing the later data of state estimation to work as static data.

If the data of obtaining among the step S1 are WAMS data, can adopt the method for recursive filtering that PMU measurement time series data is carried out the mean filter processing, the mean value computation formula is

Wherein N is in practical engineering application desirable 5.If detecting a certain moment PMU measures with a last moment measured value difference bigger, take off PMU measuring value at a moment again, judge that with this PMU measures bad data and still has big disturbance event to take place, value replaces if bad data is just used constantly, if judge it is that big disturbance event takes place, will start the transient stability quantitative estimation method.

By adopting the mode of mean filter, bad data and big disturbance anticipation, improve the availability of PMU data, and in time start the transient stability predictor method.

Among the step S2, be illustrated in figure 1 as electrical network arbitrary node representative model synoptic diagram, the electrical network arbitrary node, according to its actual electrical network parts that connect, according to meritorious this node equivalence transfer power of statistics that flows to, form node equivalence transmission of electricity model synoptic diagram as shown in Figure 2, this equivalence transmission of electricity model is different from traditional Dai Weinan equivalence method, voltage stability that can all nodes of comprehensive assessment electrical network, as shown in Figure 2, this equivalence transmission of electricity model parameter comprises equivalent source electromotive force E _E, equivalent branch impedance mould Z _EWith angle of impedance α.

According to the local equivalence circulation of node power, the equivalence transmission of electricity model parameter of each node of on-line tracing identification, the method that discrimination method can adopt many trends method of section, single trend method of section and calculation of short-circuit current result to combine, the confidence level of raising identification result.

Try to achieve node static voltage stability nargin index V according to each node equivalence transmission of electricity model parameter among the step S3 _SiMethod comprises: find the solution and find the solution according to maximum active power according to modulus of impedance.Find the solution according to modulus of impedance

Wherein, Z _LExpression equivalent load modulus of impedance.Find the solution according to maximum active power

P wherein _CrFor the character with regard to load side is seen, when taking into account load power factor, maximum meritorious transport capacity

Φ and α are respectively equivalent load power-factor angle and the angle of impedance of node equivalence transmission of electricity model.

V _SiBe 0 o'clock, reach the static voltage stability critical point, according to the static voltage stability nargin index V of each node _SiThe value size sorts, can determine which node is relative weak node, realize the location of relative weak node or weakness zone, for ease of quantitative evaluation different running method or false voltage stability margin situation, can try to achieve electrical network averaged static voltage stability margin index V _Msi, V _MsiComputing formula is

Wherein n is the grid nodes number, V _SiiThe static voltage stability nargin index of representing i node.The V that also can compare the minimum node under the different modes _SiWeigh each mode voltage degree of stability.

If the data of obtaining are transient state fault time-domain-simulation data, computing node static voltage stability nargin index V among the step S3 _SiMethod is: when transient state merit angle or transient voltage are all stablized, can be according to maximal phase to merit angle single pendulum reentry point, perhaps minimum voltage falls a little definite evaluation time section, when transient state merit angle unstability or transient voltage unstability, can spend greater than 180 merit angle reentry point according to maximal phase, perhaps minimum voltage falls a little definite evaluation time section, the data of discontinuity surface are carried out the assessment of static voltage stability situation during then in the evaluation time section each, ask the averaged static voltage stability margin index V of all sections in the whole evaluation time section at last again _MsiMean value V _Tmsi, perhaps minimum static voltage stability nargin index V _SiminMean value V _Tsimin, as the voltage stability margin index of described transient state time-domain-simulation data.Utilize this method can realize the voltage unstability order of severity ordering of transient state fault collection.

Be illustrated in figure 3 as virtual reactive-load compensation and network loss and concern synoptic diagram, according to shown in Figure 3, can try to achieve the meritorious P of the current circulation of node _EThe time, make the minimum required idle value of equivalence transmission of electricity model corresponding virtual shown in Figure 2 active loss, calculate each node reactive-load compensation evaluation index Q _Ci, make up node reactive-load compensation evaluation index Q among the step S4 _CiAfter, with the reactive-load compensation evaluation index Q of all nodes of electrical network _CiAverage, try to achieve the average reactive-load compensation vacancy of electrical network index

And then whole reactive-load compensation vacancy proficiency assessment under the current method of operation of realization electrical network.

Wherein, n represents the number of all nodes of electrical network, Q _CijThe reactive-load compensation evaluation index of representing j node.

Fast cut back is estimated synoptic diagram as shown in Figure 4, among the step S5, and computing node static voltage stability nargin index V _SiLess than early warning sill value N _CrThe time the method estimated of the cutting load of node be:

According to node equivalence transmission of electricity model parameter, can onlinely try to achieve corresponding static voltage stability virtual linear border δ under this equivalence transmission of electricity model _Cr, this border in the expression formula of power-factor angle and phase angle coordinate space is:

${\mathrm{\δ}}_{\mathrm{cr}}=\left\{\begin{array}{c}-0.5\mathrm{\Φ}+0.5\mathrm{\α}(-\mathrm{\α}\≤\mathrm{\Φ}\≤\mathrm{\π}/2)\\ 0.5\mathrm{\Φ}+1.5\mathrm{\α}(-\mathrm{\π}/2\≤\mathrm{\Φ}\≤-\mathrm{\α})\end{array}\right.$

Wherein, Φ, α are respectively equivalent load power-factor angle and the angle of impedance of node equivalence transmission of electricity model.

(1) constant power factor cutting load amount is:

Meritorious excision amount Δ P ₁:

$\mathrm{\Δ}{P}_1=\frac{{E_E}^2\cos \mathrm{\Φ}\sin ({\mathrm{\δ}}_0-{\mathrm{\δ}}_1+\mathrm{\Φ}-\mathrm{\α})\sin ({\mathrm{\δ}}_1-{\mathrm{\δ}}_0)}{Z_E{\sin }^2(\mathrm{\Φ}-\mathrm{\α})}$

Wherein, δ ₀And δ ₁Be respectively the equivalent merit angle of initial launch point and adjusting back operating point, δ ₁=N _Crδ _Cr,

Idle excision amount Δ Q ₁=Δ P ₁Tan Φ;

(2) minimum cutting load amount

Equivalence merit angle variable quantity $\mathrm{\Δ\δ}=2\frac{{\mathrm{\δ}}_0-N_{\mathrm{cr}}{\mathrm{\δ}}_{\mathrm{cr}0}}{0.5N_{\mathrm{cr}}+2},$

Equivalent Power Factor angle variable quantity

Be Φ ₁=Φ ₀-ΔΦ, δ ₁=δ ₀-Δ δ, Φ ₀And Φ ₁Be respectively the equivalent load power-factor angle of initial launch point and adjusting back operating point, δ _Cr0Be the corresponding critical phase angular difference of initial launch point.

Again with Φ ₁And δ ₁Back operating point P is regulated in substitution ₁Computing formula:

$P_1=\frac{{E_E}^2\cos {\mathrm{\Φ}}_1[\cos (2{\mathrm{\δ}}_1+{\mathrm{\Φ}}_1-\mathrm{\α})-\cos ({\mathrm{\Φ}}_1-\mathrm{\α})]}{2Z_E{\sin }^2({\mathrm{\Φ}}_1-\mathrm{\α})}$

According to P ₁Find the solution and regulate back operating point Q ₁=P ₁Tan Φ ₁,

Obtain minimum meritorious excision amount Δ P ₁=P ₀-P ₁,

Corresponding idle excision amount Δ Q=Q ₀-Q ₁

A kind of receiving end electrical network overall process voltage based on the multiple response information source provided by the invention is stablized the voltage of situation assessment preventing control method and is stablized overall process prevention and control structural drawing as shown in Figure 5.Can adopt the mode of off-line tasks in parallel to carry out respectively at N-1, N-2, transient state fault collection or medium-term and long-term calculation task and filter out more serious forecast failure, adopt the tasks in parallel pattern to realize that the voltage of the various anticipation methods of operation and fault collection stablize situation assessment and aid decision making, raising is stablized assess effectiveness to the voltage of a large amount of forecast failures.And N-1 that can static voltage stability is more serious, N-2 fault are utilized transient state or the further verification of medium-term and long-term emulation.

For the WAMS real-time measuring data, stablize estimating velocity for improving on-Line Voltage, the pattern that adopts online tasks in parallel is carried out voltage to the actual measuring point of PMU stablize the situation assessment, realize the identification of weak node or weakness zone, and assess the reactive-load compensation level of each node and the cutting load estimator of low-voltage stabilizing nargin node synchronously.

At different off-lines or online operation of power networks data section, statistics provides the cutting load of static voltage stability nargin index, reactive-load compensation level and the weak node of each node and estimates in advance.At different forecast failure collections, give be out of order order of severity quantizating index and corresponding reactive-load compensation and cutting load aid decision making reference policy, for operation, mode, planning personnel's reference.

Should be noted that at last: 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 the present invention is had been described in detail, those of ordinary skill in the field are to be understood that: still can make amendment or be equal to replacement the specific embodiment of the present invention, and do not break away from any modification of spirit and scope of the invention or be equal to replacement, it all should be encompassed in the middle of the claim scope of the present invention.

Claims (11)

1. the receiving end line voltage based on response is stablized the assessment of overall process situation and preventing control method, it is characterized in that described method comprises:

Step S1 obtains various off-line simulation data or real-time measuring data, according to the corresponding scene of the described data obtained respectively unloading be static data formatted file or Temporal Data formatted file;

Described off-line simulation data are transient state fault time-domain-simulation data, the electric network data of described real-time measuring data for measuring in real time by SCADA system, EMS, WAMS, DTS or DCS;

Step S2 adds up the equivalent power P that described node circulates to all electric network elements that arbitrary node connects by meritorious the flow direction _E+ jQ _E, make up the equivalence transmission of electricity model of described node according to described node actual transfer power, in conjunction with node voltage U, adopt the on-line tracing discrimination method to try to achieve the equivalence transmission of electricity model parameter of each described node;

Step S3 tries to achieve node static voltage stability nargin index V according to the described equivalence transmission of electricity model parameter of described each node _Si, according to the static voltage stability nargin index V of described each node _SiValue is determined relative weak node;

Step S4 is according to the described equivalence transmission of electricity model parameter of described each node, in conjunction with the meritorious value of the current circulation of described node P _E, try to achieve virtual active loss under the described node equivalence transmission of electricity model correspondence needed idle amount Q when minimum _Min, make up node reactive-load compensation evaluation index $Q_{\mathrm{ci}}=\left|\frac{Q_E-Q_{\min }}{Q_E}\right|;$

Step S5 sets the early warning sill value N of described node static voltage stability nargin index _Cr, calculate described node static voltage stability nargin index V _SiLess than described early warning sill value N _CrThe cutting load of the relative weak node of Shi Suoshu is estimated.

2. the method for claim 1, it is characterized in that, among the described step S1, be the flow data formatted file if response data is the data conversion storage of trend section character, if the data of transient state or dynamic time-domain-simulation class, unloading is the time series formatted file;

If response data is the SCADA system data, directly utilizes the later data of SCADA system state estimation to be used as static data and handle.

3. the method for claim 1 is characterized in that, among the described step S1,

If the data of obtaining are WAMS data, adopt the method for recursive filtering that PMU measurement time series data is carried out the mean filter processing, the mean value computation formula is

N gets 5 in practical engineering application;

If detecting a certain moment PMU measures with a last moment measured value difference bigger, take off PMU measuring value at a moment again, judge that with this it is that bad data or big disturbance event take place that PMU measures, if judge that it is bad data that PMU measures, using constantly, the PMU measuring value replaces, if judge it is that big disturbance event takes place, start the transient stability quantitative estimation method.

4. the method for claim 1 is characterized in that, the transmission of electricity of equivalence described in described step S2 model parameter comprises equivalent source electromotive force E _E, equivalent branch impedance mould Z _EWith angle of impedance α.

5. method as claimed in claim 4 is characterized in that, the described equivalence transmission of electricity model parameter according to described each node among the described step S3 is tried to achieve node static voltage stability nargin index V _SiMethod comprises: find the solution and find the solution according to maximum active power according to modulus of impedance;

According to modulus of impedance solution node static voltage stability nargin index

Wherein, Z _LExpression equivalent load modulus of impedance;

According to maximum active power solution node static voltage stability nargin index

Wherein, P _CrBe the meritorious transport capacity of maximum,

Φ and α are respectively equivalent load power-factor angle and the angle of impedance of node equivalence transmission of electricity model.

6. method as claimed in claim 5 is characterized in that, among the described step S3 according to the static voltage stability nargin index V of each node _SiThe value size sorts, and determines relative weak node, realizes the location of relative weak node or weakness zone;

By comparing the V of minimum node under the different modes _SiWeigh each mode voltage degree of stability;

Calculate electrical network averaged static voltage stability margin index

N is the grid nodes number.

7. method as claimed in claim 5 is characterized in that, if the described data of obtaining are transient state fault time-domain-simulation data, and computing node static voltage stability nargin index V among the described step S3 _SiMethod is:

When transient state merit angle or transient voltage were all stablized, to merit angle single pendulum reentry point, perhaps minimum voltage fell and a little determines the evaluation time section according to maximal phase; When transient state merit angle unstability or transient voltage unstability, can spend greater than 180 merit angle reentry point according to maximal phase, perhaps minimum voltage falls a little definite evaluation time section;

The data of discontinuity surface are carried out the assessment of static voltage stability situation during in the described evaluation time section each, ask the averaged static voltage stability margin index V of all sections _MsiMean value V _Tmsi, perhaps minimum static voltage stability nargin index V _SiminMean value V _Tsimin, as the voltage stability margin index of described transient state time-domain-simulation data.

8. method as claimed in claim 4 is characterized in that, makes up node reactive-load compensation evaluation index Q among the described step S4 _CiAfter, with the reactive-load compensation evaluation index Q of all nodes of electrical network _CiAverage, try to achieve the average reactive-load compensation vacancy of electrical network index

Realize whole reactive-load compensation vacancy proficiency assessment under the current method of operation of electrical network;

Wherein, n represents the number of all nodes of electrical network, Q _CijThe reactive-load compensation evaluation index of representing j node.

9. method as claimed in claim 4 is characterized in that, among the described step S5, and computing node static voltage stability nargin index V _SiLess than early warning sill value N _CrThe time cutting load method estimated be:

According to described node equivalence transmission of electricity model parameter, try to achieve corresponding static voltage stability virtual linear border δ under the described equivalence transmission of electricity model _Cr, described border in the expression formula of power-factor angle and phase angle coordinate space is:

${\mathrm{\δ}}_{\mathrm{cr}}=\left\{\begin{array}{c}-0.5\mathrm{\Φ}+0.5\mathrm{\α}(-\mathrm{\α}\≤\mathrm{\Φ}\≤\mathrm{\π}/2)\\ 0.5\mathrm{\Φ}+1.5\mathrm{\α}(-\mathrm{\π}/2\≤\mathrm{\Φ}\≤-\mathrm{\α})\end{array}\right.$

Wherein, Φ, α are respectively equivalent load power-factor angle and the angle of impedance of node equivalence transmission of electricity model;

(1) constant power factor cutting load amount is:

Meritorious excision amount Δ P ₁:

$\mathrm{\Δ}{P}_1=\frac{{E_E}^2\cos \mathrm{\Φ}\sin ({\mathrm{\δ}}_0-{\mathrm{\δ}}_1+\mathrm{\Φ}-\mathrm{\α})\sin ({\mathrm{\δ}}_1-{\mathrm{\δ}}_0)}{Z_E{\sin }^2(\mathrm{\Φ}-\mathrm{\α})}$

Wherein, δ ₀And δ ₁Be respectively the equivalent merit angle of initial launch point and adjusting back operating point, δ ₁=N _Crδ _Cr

Idle excision amount Δ Q ₁=Δ P ₁Tan Φ;

(2) minimum cutting load amount:

Equivalence merit angle variable quantity $\mathrm{\Δ\δ}=2\frac{{\mathrm{\δ}}_0-N_{\mathrm{cr}}{\mathrm{\δ}}_{\mathrm{cr}0}}{0.5N_{\mathrm{cr}}+2},$

Equivalent Power Factor angle variable quantity $\mathrm{\Δ\Φ}=\frac{{\mathrm{\δ}}_0-N_{\mathrm{cr}}{\mathrm{\δ}}_{\mathrm{cr}0}}{0.5N_{\mathrm{cr}}+2},$

Be Φ ₁=Φ ₀-ΔΦ, δ ₁=δ ₀-Δ δ, Φ ₀And Φ ₁Be respectively the equivalent load power-factor angle of initial launch point and adjusting back operating point, δ _Cr0Be the corresponding critical phase angular difference of initial launch point;

With Φ ₁And δ ₁Back operating point P is regulated in substitution ₁Computing formula:

$P_1=\frac{{E_E}^2\cos {\mathrm{\Φ}}_1[\cos (2{\mathrm{\δ}}_1+{\mathrm{\Φ}}_1-\mathrm{\α})-\cos ({\mathrm{\Φ}}_1-\mathrm{\α})]}{2Z_E{\sin }^2({\mathrm{\Φ}}_1-\mathrm{\α})}$ After find the solution P ₁,

According to P ₁Find the solution and regulate back operating point Q ₁=P ₁Tan Φ ₁,

Obtain minimum meritorious excision amount Δ P ₁=P ₀-P ₁,

Corresponding idle excision amount Δ Q=Q ₀-Q ₁

10. the method for claim 1, it is characterized in that, adopt the mode of off-line tasks in parallel to carry out respectively at N-1, N-2, transient state fault collection or medium-term and long-term calculation task and filter out more serious forecast failure, adopt the tasks in parallel pattern to realize that the voltage of the various anticipation methods of operation and fault collection stablize situation and assesses and aid decision making; And the N-1 that static voltage stability is more serious, N-2 fault are utilized transient state or the further verification of medium-term and long-term emulation.

11. the method for claim 1, it is characterized in that, for the WAMS real-time measuring data, the pattern that adopts online tasks in parallel is carried out voltage to the actual measuring point of PMU and is stablized the situation assessment, and assesses the reactive-load compensation level of each node and the cutting load estimator of low-voltage stabilizing nargin node synchronously;

At different off-lines or online operation of power networks data section, statistics provides the cutting load of static voltage stability nargin index, reactive-load compensation level and the weak node of each node and estimates in advance; At different forecast failure collections, give be out of order order of severity quantizating index and corresponding reactive-load compensation and cutting load aid decision making reference policy, for operation, mode, planning personnel's reference.

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