CN104484520A - Equivalent wind speed method for processing wind power plant static power equivalent dispersion problems - Google Patents

Abstract

The invention relates to the technical field of wind power plant static power equivalent processing, in particular to an equivalent wind speed method for processing wind power plant static power equivalent dispersion problems. The method includes the steps of firstly, analyzing output dispersion of each wind turbine generator set of a wind power plant; analyzing the different positions and interactional wind power plant internal wind energy dispersion of the wind turbine generator sets, and using minimum error circulation search to select overall wind power plant operation behaviors and the wind turbine generator sets of wind power plant internal dispersion; secondly, determining equivalent wind speed; using N times of the output power of the wind turbine generator sets driven by equivalent wind speed as the algorithm of the total output power of a wind power plant; thirdly, describing the error analysis of wind power plant static behavioral equivalence on the basis of the equivalent wind speed; comparing and evaluating the output of wind power plant equivalent models and the actual output of the wind power plant. The equivalent wind speed method has the advantages that the overall behaviors of the wind power plant can be described precisely, power grid dispatching and reasonable production plant arrangement are benefited, system backup capacity is reduced, and an important analysis method for correctly evaluating the influence of the grid-connected wind power plant on power grid operation is provided.

Description

A kind of equivalent wind speed method processing the equivalent dispersion problem of wind energy turbine set static power

Technical field

The present invention relates to the equivalent processing technology field of wind energy turbine set static power, particularly relate to a kind of equivalent wind speed method processing the equivalent dispersion problem of wind energy turbine set static power.

Background technology

Large-scale Wind Power field mainly comes from the stochastic volatility of its output power for the impact of electric system, and this characteristic is derived from the natural characteristic of wind energy, and due to the difference of wind energy distribution, in wind energy turbine set, each unit output power also exists very large dispersiveness.Current research is wind farm grid-connected to the method that system has an impact is: the Equivalent Model first setting up wind energy turbine set and electrical network, carries out correlative study on this basis by simulation calculation.Wherein network equivalence model comparative maturity, and to set up the higher wind energy turbine set Equivalent Model of precision be the important topic that this field is urgently studied always.

Wind energy turbine set Equivalent Model major function is the change by Power Output for Wind Power Field, reflects the characteristic that actual wind energy fluctuates, and its mathematics essence is the wind speed by injecting whole wind energy turbine set, by the process of mathematical model, changes into the output power of wind energy turbine set.Therefore, the process of injecting wind speed will directly affect the precision of wind energy turbine set Equivalent Model.

The research method of traditional wind energy turbine set Equivalent Model, as shown in Figure 1 and Figure 2, normally first calculate the output power of certain typhoon group of motors under actual measurement wind speed, then the N of this power (separate unit machine) times (N is running Wind turbines number of units in wind energy turbine set) is carried out the output of equivalently represented whole wind energy turbine set.Its essence directly utilizes the actual measurement wind speed of separate unit Wind turbines as the injection wind speed of whole wind energy turbine set.And actual conditions are: the usual floor area of wind energy turbine set is comparatively large, the floor area of the wind energy turbine set of single-machine capacity 850kW, total installed capacity 49.3MW has exceeded 16km ², in the region of such yardstick, by the impact of wake effect, between the Wind turbines that arrangement is comparatively concentrated, the distributional difference of wind energy is fairly obvious, thus result in Wind turbines output power and have very large dispersiveness.Along with wind energy turbine set floor area is increasing, the blower fan number of units comprised gets more and more, and the spatial distribution differences of wind energy can be more obvious.Although therefore above-mentioned classic method is simple, low precision, affects the accuracy of power supply management department to integrated wind plant postitallation evaluation, is unfavorable for, by the electrical network actual conditions reasonable arrangement production schedule, adding system reserve capacity.

Summary of the invention

For above-mentioned problems of the prior art, the invention provides a kind of equivalent wind speed method processing the equivalent dispersion problem of wind energy turbine set static power.Object is to provide a kind of analysis accurately, contributes to the dispatching of power netwoks reasonable arrangement production schedule, reduces system reserve capacity, correctly can evaluate the equivalent wind speed method of integrated wind plant on the equivalent dispersion problem of process wind energy turbine set static power that operation of power networks affects simultaneously.

The object of the invention is to be realized by following technical scheme:

Process an equivalent wind speed method for the equivalent dispersion problem of wind energy turbine set static power, it comprises the following steps:

(1) each Wind turbines of wind energy turbine set is exerted oneself dispersed analysis;

1. get the complete service data in wind energy turbine set each Wind turbines a period of time, calculate mean wind speed, the average power of wind energy turbine set;

2. find out the dispersiveness of exerting oneself of wind speed and the maximum some typhoon group of motors of power difference, be considered as the dispersiveness of exerting oneself of wind energy turbine set;

3. on same figure, draw wind speed and the maximum some typhoon group of motors of power difference wind speed, power contrast, and find out each moment wind speed, the maximal value of power and minimum value, draw the envelope of wind speed, power;

4. the difference of each moment wind speed, power maximal and minmal value is calculated, i.e. the deviation of wind speed, power, such as formula 1., 2., i.e. the dispersiveness of exerting oneself of wind energy turbine set;

$\mathrm{\Δ}{P}_t=\underset{i=1}{\overset{N}{\max }}\left(P_{\mathrm{it}}\right)-\underset{i=1}{\overset{N}{\min }}\left(P_{\mathrm{it}}\right)$ ①

$\mathrm{\Δ}{V}_t=\underset{i=1}{\overset{N}{\max }}\left(V_{\mathrm{it}}\right)-\underset{i=1}{\overset{N}{\min }}\left(V_{\mathrm{it}}\right)$ ②

In formula: △ P _tfor the deviation of certain moment output of wind electric field; P _tpower is carved when being a typhoon group of motors; △ V _tfor the deviation of certain moment wind farm wind velocity; V _tfor the wind speed of certain moment one typhoon group of motors;

5. for the ease of weighing the dispersiveness of exerting oneself of wind energy turbine set, mark the one being carried out for power, wind speed rated power, wind rating, obtains the ratio epsilon that deviation accounts for rated power _t, ε _t', such as formula 3., 4., draw output of wind electric field dispersiveness figure;

${\mathrm{\ϵ}}_t=\frac{\mathrm{\Δ}{P}_t}{S_N}\×100\%$ ③

${{\mathrm{\ϵ}}_t}^{\′}=\frac{\mathrm{\Δ}{V}_t}{V_N}\×100\%$ ④

As wind energy turbine set ε _t, ε _t' be all less than 10%, prove that the operation conditions of wind energy turbine set every typhoon group of motors is substantially identical, be considered as wind energy turbine set without to exert oneself dispersiveness, work as ε _t, ε _t' be greater than 10%, prove that the operation conditions of wind energy turbine set every typhoon group of motors has certain gap, in the modeling and various grid-connected research of wind energy turbine set, need the dispersiveness of exerting oneself taking into full account wind energy turbine set;

(2) determination of equivalent wind speed: when each Wind turbines of wind energy turbine set is regularly arranged, statistical procedures is done to the wind speed at wind energy turbine set 4 drift angle places and obtains equivalent wind speed, and using the N of the Wind turbines output power under the driving of this equivalent wind speed doubly as the algorithm of wind energy turbine set gross output;

Provide the Wind speed model of this wind energy turbine set, such as formula 5.,

$v=\frac{1}{N}\underset{i=1}{\overset{N}{\mathrm{\Σ}}}{v}_i$ ⑤

In formula, v is mean wind speed, unit: m/s; v _ibe the wind speed of the i-th typhoon group of motors, unit: m/s; V is the mean value of wind energy turbine set each Wind turbines record wind speed, usually selects the data of representational some typhoon group of motors representatively to average;

(3) error analysis of wind energy turbine set static behavior equivalence is described: adopt mean absolute percentage error based on equivalent wind speed, the output of wind energy turbine set Equivalent Model and the actual output of wind energy turbine set are analyzed, the precision of the method is evaluated with this, and the advantage of relative classic method;

What error assessment standard adopted is traditional mean absolute percentage error, if V _aactual value, and V _fbe predicted value, so percentage error is defined as:

⑥

PE＝(V _f-V _a)/V _a×100％

Absolute percent error is defined as:

APE＝|PE| ⑦

Mean absolute percentage error is defined as:

$\mathrm{MAPE}=\frac{1}{N}\underset{i=1}{\overset{N}{\mathrm{\Σ}}}{\mathrm{APE}}_i$ ⑧

Maximum absolute percent error is defined as:

${\mathrm{APE}}_{\max }=\underset{i=1}{\overset{N}{\max }}\left({\mathrm{APE}}_i\right)$ ⑨

The actual measurement air speed data providing wind energy turbine set record is as input, and when the output of wind energy turbine set Equivalent Model conforms to substantially with the actual output of wind energy turbine set, the model being wind energy turbine set is effective.

The described wind energy turbine set regularly arranged with Wind turbines 4 drift angle places;

If wind energy turbine set is square region, then select the data of the Wind turbines record at wind energy turbine set outermost four summits place; If wind energy turbine set is border circular areas, select the data of equidistant four typhoon group of motors records in the outermost of wind energy turbine set.

Advantage of the present invention and beneficial effect are:

The present invention can describe the global behavior of wind energy turbine set more accurately than conventional method, not only contribute to the dispatching of power netwoks reasonable arrangement production schedule, reducing system reserve capacity, important analysis means can also be provided for correctly evaluating the impact of integrated wind plant on operation of power networks simultaneously.

For a better understanding of the present invention, below in conjunction with specific embodiments and the drawings, the present invention is described in further detail;

Accompanying drawing explanation

Fig. 1 is Power Output for Wind Power Field and measured power correlation curve schematic diagram under existing wind energy turbine set equivalence method;

Fig. 2 is wind energy turbine set output power error curve synoptic diagram under existing wind energy turbine set equivalence method;

Fig. 3 is the maximum wind velocity at wind energy turbine set 4 drift angle places that the inventive method is chosen, minimum windspeed and equivalent wind speed schematic diagram thereof;

Fig. 4 is wind energy turbine set 4 drift angle place peak power outputs, minimum output power and equivalent output powers schematic diagram thereof that the inventive method is chosen;

Fig. 5 is that the wind energy turbine set general power that calculates of existing method and the inventive method and real total power contrast schematic diagram;

Fig. 6 is the graph of errors schematic diagram adopting the overall output power of the wind energy turbine set of equivalent wind speed and real total power.

Specific implementation method

The present invention is a kind of equivalent wind speed method processing the equivalent dispersion problem of wind energy turbine set static power, and in order to solve the output of wind electric field dispersion problem that traditional wind energy turbine set static power Equivalent Model cannot process, concrete grammar is as follows:

1, each Wind turbines of wind energy turbine set is exerted oneself dispersed analysis.

By the statistical procedures to Wind turbines actual operating data each in wind energy turbine set, analyze the dispersiveness of the inner wind energy of position wind energy turbine set that are different and that influence each other and produce due to each typhoon group of motors, choose the Wind turbines best embodying the behavior of wind energy turbine set overall operation and wind energy turbine set inner dispersion with least error cyclic search;

(1) get the complete service data in wind energy turbine set each Wind turbines a period of time, calculate mean wind speed, the average power of wind energy turbine set;

(2) find out the dispersiveness of exerting oneself of wind speed and the maximum some typhoon group of motors of power difference, be considered as the dispersiveness of exerting oneself of wind energy turbine set;

(3) on same figure, draw wind speed and the maximum some typhoon group of motors of power difference wind speed, power contrast, and find out each moment wind speed, the maximal value of power and minimum value, draw the envelope of wind speed, power;

(4) difference of each moment wind speed, power maximal and minmal value is calculated, i.e. the deviation of wind speed, power, such as formula (1), (2), i.e. the dispersiveness of exerting oneself of wind energy turbine set;

$\mathrm{\Δ}{P}_t=\underset{i=1}{\overset{N}{\max }}\left(P_{\mathrm{it}}\right)-\underset{i=1}{\overset{N}{\min }}\left(P_{\mathrm{it}}\right)---\left(1\right)$

$\mathrm{\Δ}{V}_t=\underset{i=1}{\overset{N}{\max }}\left(V_{\mathrm{it}}\right)-\underset{i=1}{\overset{N}{\min }}\left(V_{\mathrm{it}}\right)---\left(2\right)$

In formula: △ P _tfor the deviation of certain moment output of wind electric field; P _tpower is carved when being a typhoon group of motors; △ V _tfor the deviation of certain moment wind farm wind velocity; V _tfor the wind speed of certain moment one typhoon group of motors;

(5) for the ease of weighing the dispersiveness of exerting oneself of wind energy turbine set, mark the one being carried out for power, wind speed rated power, wind rating, obtains the ratio epsilon that deviation accounts for rated power _t, ε _t', such as formula (3), (4), draw output of wind electric field dispersiveness figure;

${\mathrm{\ϵ}}_t=\frac{\mathrm{\Δ}{P}_t}{S_N}\×100\%---\left(3\right)$

${{\mathrm{\ϵ}}_t}^{\′}=\frac{\mathrm{\Δ}{V}_t}{V_N}\×100\%---\left(4\right)$

As wind energy turbine set ε _t, ε _t' be all less than 10%, prove that the operation conditions of wind energy turbine set every typhoon group of motors is substantially identical, be considered as wind energy turbine set without to exert oneself dispersiveness, work as ε _t, ε _t' be greater than 10%, prove that the operation conditions of wind energy turbine set every typhoon group of motors has certain gap, in the modeling and various grid-connected research of wind energy turbine set, need the dispersiveness of exerting oneself taking into full account wind energy turbine set.

Fig. 1 is N certain typhoon group of motors output power doubly and the comparison diagram of whole wind energy turbine set general power, although this figure shows to adopt the N of certain typhoon group of motors output power doubly to carry out the method for the output of equivalently represented whole wind energy turbine set simply, can bring obvious error.Fig. 2 then gives error between the two, and wherein maximum error power reaches 18MW, and average error power is about 11MW, and average error power is about rated power 22%.

2, the determination of equivalent wind speed.

The present invention proposes a kind of specific implementation using the wind speed mean value at regularly arranged wind energy turbine set 4 the drift angle places of Wind turbines as equivalent wind speed, and using the N of the Wind turbines output power under the driving of this equivalent wind speed doubly as the algorithm of wind energy turbine set gross output.

Provide the Wind speed model of this wind energy turbine set, such as formula (5),

$v=\frac{1}{N}\underset{i=1}{\overset{N}{\mathrm{\Σ}}}{v}_i---\left(5\right)$

In formula, v is mean wind speed, unit: m/s; v _ibe the wind speed of the i-th typhoon group of motors, unit: m/s; V is the mean value of wind energy turbine set each Wind turbines record wind speed, and the Wind turbines number of usual wind energy turbine set is a lot, and the possibility obtaining surveying air speed data is one by one smaller, therefore needs to select representational a few number of units according to representatively averaging;

If wind energy turbine set is square region, select the data of the Wind turbines record at wind energy turbine set outermost four summits place, if wind energy turbine set is border circular areas, select the data of equidistant four typhoon group of motors records in the outermost of wind energy turbine set.Find by contrasting with the mean wind speed of all Wind turbines of actual wind energy turbine set, the average power of this four typhoons group of motors and the average power of whole wind energy turbine set the most close.So, by asking the mean wind speed of mean wind speed as wind energy turbine set of wind energy turbine set edge four typhoon group of motors.Fig. 3 is wind energy turbine set 4 drift angle place maximum wind velocities, minimum windspeed, mean wind speeds; Fig. 4 is wind energy turbine set 4 drift angle place peak power outputs, minimum output power, average output power curves.

3, the error analysis of wind energy turbine set static behavior equivalence is described based on equivalent wind speed.

Adopt mean absolute percentage error, the output of wind energy turbine set Equivalent Model and the actual output of wind energy turbine set are analyzed, evaluate the precision of the method with this, and the advantage of relative classic method;

What error assessment standard adopted is traditional mean absolute percentage error, MeanAbsolute Percentage Error, is called for short MAPE, if V _aactual value, and V _fpredicted value, so percentage error, Percentage Error, is called for short PE, is defined as:

PE＝(V _f-V _a)/V _a×100％ (6)

Absolute percent error, Absolute Percentage Error, is called for short APE, is defined as:

APE＝|PE| (7)

Mean absolute percentage error is defined as:

$\mathrm{MAPE}=\frac{1}{N}\underset{i=1}{\overset{N}{\mathrm{\Σ}}}{\mathrm{APE}}_i---\left(8\right)$

Maximum absolute percent error is defined as:

${\mathrm{APE}}_{\max }=\underset{i=1}{\overset{N}{\max }}\left({\mathrm{APE}}_i\right)---\left(9\right)$

The actual measurement air speed data providing wind energy turbine set record is as input, and when the output of wind energy turbine set Equivalent Model conforms to substantially with the actual output of wind energy turbine set, the model being wind energy turbine set is effective.

Fig. 5 is the wind energy turbine set general power and measured power correlation curve that adopt equivalent wind speed to calculate, and Fig. 6 is corresponding graph of errors.As seen from the figure, the maximum error of this equivalence method is no more than 6.5MW, and average error power is 3.3MW, and average error power is equivalent to 6.6% of the total rated power of wind energy turbine set.Above analytic explanation: adopt equivalent wind speed, namely all driving by equivalent wind speed of each Wind turbines of wind energy turbine set is set to, now corresponding wind energy turbine set general power and wind energy turbine set real total power more close, average error is no more than 6.6%, far below the error rate of classic method 22%.

Claims (2)

1. process an equivalent wind speed method for the equivalent dispersion problem of wind energy turbine set static power, it is characterized in that it comprises the following steps:

(1) each Wind turbines of wind energy turbine set is exerted oneself dispersed analysis;

1. get the complete service data in wind energy turbine set each Wind turbines a period of time, calculate mean wind speed, the average power of wind energy turbine set;

2. find out the dispersiveness of exerting oneself of wind speed and the maximum some typhoon group of motors of power difference, be considered as the dispersiveness of exerting oneself of wind energy turbine set;

3. on same figure, draw wind speed and the maximum some typhoon group of motors of power difference wind speed, power contrast, and find out each moment wind speed, the maximal value of power and minimum value, draw the envelope of wind speed, power;

4. the difference of each moment wind speed, power maximal and minmal value is calculated, i.e. the deviation of wind speed, power, such as formula 1., 2., i.e. the dispersiveness of exerting oneself of wind energy turbine set;

${\mathrm{\ΔP}}_t=\underset{i=1}{\overset{N}{\max }}\left(P_{\mathrm{it}}\right)-\underset{i=1}{\overset{N}{\min }}\left(P_{\mathrm{it}}\right)$ ①

${\mathrm{\ΔV}}_t=\underset{i=1}{\overset{N}{\max }}\left(V_{\mathrm{it}}\right)-\underset{i=1}{\overset{N}{\min }}\left(V_{\mathrm{it}}\right)$ ②

In formula: △ P _tfor the deviation of certain moment output of wind electric field; P _tpower is carved when being a typhoon group of motors; △ V _tfor the deviation of certain moment wind farm wind velocity; V _tfor the wind speed of certain moment one typhoon group of motors;

5. for the ease of weighing the dispersiveness of exerting oneself of wind energy turbine set, mark the one being carried out for power, wind speed rated power, wind rating, obtains the ratio epsilon that deviation accounts for rated power _t, ε _t', such as formula 3., 4., draw output of wind electric field dispersiveness figure;

${\mathrm{\ϵ}}_t=\frac{{\mathrm{\ΔP}}_t}{S_N}\×100\%$ ③

${{\mathrm{\ϵ}}_t}^{\′}=\frac{{\mathrm{\ΔV}}_t}{V_N}\×100\%$ ④

As wind energy turbine set ε _t, ε _t' be all less than 10%, prove that the operation conditions of wind energy turbine set every typhoon group of motors is substantially identical, be considered as wind energy turbine set without to exert oneself dispersiveness, work as ε _t, ε _t' be greater than 10%, prove that the operation conditions of wind energy turbine set every typhoon group of motors has certain gap, in the modeling and various grid-connected research of wind energy turbine set, need the dispersiveness of exerting oneself taking into full account wind energy turbine set;

(2) determination of equivalent wind speed: when each Wind turbines of wind energy turbine set is regularly arranged, statistical procedures is done to the wind speed at wind energy turbine set 4 drift angle places and obtains equivalent wind speed, and using the N of the Wind turbines output power under the driving of this equivalent wind speed doubly as the algorithm of wind energy turbine set gross output;

Provide the Wind speed model of this wind energy turbine set, such as formula 5.,

$v=\frac{1}{N}\underset{i=1}{\overset{N}{\mathrm{\Σ}}}{v}_i$ ⑤

In formula, v is mean wind speed, unit: m/s; v _ibe the wind speed of the i-th typhoon group of motors, unit: m/s; V is the mean value of wind energy turbine set each Wind turbines record wind speed, usually selects the data of representational some typhoon group of motors representatively to average;

(3) error analysis of wind energy turbine set static behavior equivalence is described: adopt mean absolute percentage error based on equivalent wind speed, the output of wind energy turbine set Equivalent Model and the actual output of wind energy turbine set are analyzed, the precision of the method is evaluated with this, and the advantage of relative classic method;

What error assessment standard adopted is traditional mean absolute percentage error, if V _aactual value, and V _fbe predicted value, so percentage error is defined as:

PE＝(V _f-V _a)/V _a×100％ ⑥

Absolute percent error is defined as:

APE＝|PE| ⑦

Mean absolute percentage error is defined as:

$\mathrm{MAPE}=\frac{1}{N}\underset{i=1}{\overset{N}{\mathrm{\Σ}}}{\mathrm{APE}}_i$ ⑧

Maximum absolute percent error is defined as:

${\mathrm{APE}}_{\max }=\underset{i=1}{\overset{N}{\mathrm{ma}}}\left({\mathrm{APE}}_i\right)$ ⑨

The actual measurement air speed data providing wind energy turbine set record is as input, and when the output of wind energy turbine set Equivalent Model conforms to substantially with the actual output of wind energy turbine set, the model being wind energy turbine set is effective.

2. a kind of equivalent wind speed method processing the equivalent dispersion problem of wind energy turbine set static power according to claim 1, is characterized in that: the described wind energy turbine set regularly arranged with Wind turbines 4 drift angle places;

If wind energy turbine set is square region, then select the data of the Wind turbines record at wind energy turbine set outermost four summits place; If wind energy turbine set is border circular areas, select the data of equidistant four typhoon group of motors records in the outermost of wind energy turbine set.