CN103427431A - Charging/discharging control method of wind farm energy storage device - Google Patents

Abstract

A charging/discharging control method of a wind farm energy storage device is characterized by controlling the charging/discharging power of the energy storage device in a wind storage integrated system based on the prediction error of a wind farm power, monitoring the change of a wind farm actual output Pmk and a wind farm prediction output Ppk in a real-time on-line manner to obtain an actual relative error epk, taking a relative error value beta=25% as the demarcation point of the energy storage huff and puff power Psk and the standby control, using an energy storage device comparator to send a control signal to an energy storage device controller according to the comparison result of the actual relative error epk and the relative error value beta, and using the energy storage device controller to control the energy storage device to charge and discharge.

Description

A kind of wind energy turbine set energy storage device charge/discharge control method

Technical field

The present invention relates to energy storage device charge/discharge control method in wind storage integral system.

Background technology

Due to fluctuation and the intermittent characteristics of wind, the fluctuation of wind power and intermittent can stability and the quality of power supply of local line voltage being exerted an influence.Up to now, the researcher has proposed multiple solution, can be divided into 2 classes: the one, carry out level and smooth its power output by the running status of regulating wind turbine, can classify as direct Power Control, but the power adjustments of the method wind energy turbine set larger to fluctuations in wind speed is limited in one's ability; The 2nd, carry out the output rating of smooth wind power field by additional energy storage device, can classify as indirect power and control, the method can realize the power adjustments of relative broad range, effectively suppresses the fluctuation of Power Output for Wind Power Field.

On June 9th, 2011, " wind farm power prediction forecast management Tentative Measures " that National Energy Board issues No. [2011] 177, energy (state newly) (hereinafter to be referred as " way ") clear scheduling and the operation of following wind energy turbine set, wind power Predicting Technique that all must be based on degree of precision and confidence level.The accurate weather information of the wind energy turbine set region relied on due to power forecast is obtained difficulty, and the simple forecast precision that relies on conventional methods such as improving the wind power forecasting model to improve wind power, be difficult to accomplish technically in a short time.

Under the prior art condition, the wind power short-term forecasting precision index is difficult to meet the requirement of electrical network and " way ".Yet, along with the development of large-scale electric energy memory technology, its flexibly electrical power " gulp down " " telling " transfer characteristic, effectively " assurance " wind-powered electricity generation is exerted oneself according to prediction curve, has indirectly improved precision and the confidence level of wind power forecast.

Aspect multiple dimensioned distribution mechanism research in the wind power short-term forecasting error on time domain, have no the pertinent literature of publishing.But, the research of the domestic and international wind power prediction error for the different time yardstick has obtained some is worth achievements of using for reference, document 1(ZHANG Bo-Ming, WU Wen-chuan, et al.Design of a Multi-time Scale Coordinated Active Power Dispatching System for Accommodating Large Scale Wind Power Penetration Automation of Electric Power Systems, 2011, 35(1): 1-6.) analyzed the wind-powered electricity generation precision of prediction characteristic that yardstick improves step by step in time, document 2(Hans Bludszuweit, Jos é Antonio Dom í nguez-Navarro, Andr é s Llombart.Statistical Analysis of Wind Power Forecast Error[J] .IEEE TRANSACTIONS ON POWER SYSTEMS, 2008, 23 (3): 983-991) propose to carry out the short-term wind power prediction error modeling based on the Gaussian random variable method.Yet the time scale in these researchs is corresponding with ultrashort-term wind power prediction, short-term forecast and medium-term forecast etc.

At present, the technical performance of dissimilar energy storage device and the application in wind-electricity integration thereof have been carried out to large quantity research both at home and abroad, and some achievements have been obtained, but these researchs are the application start in wind-electricity integration for single energy storage device mostly, and rarely seen have on consideration particular type energy storage device technical and economic peculiarities basis, in conjunction with electric network performance, energy storage is discussed and is improved the method for wind power forecast precision and principle etc., need to further go deep into.Chinese patent 201120143895 and 201010555730 etc. is for various dissimilar ting model small-power energy storage devices, Mathematical Modeling based on certain also controls according to the preparation technology of energy storage device and self electric physical characteristic that it discharges and recharges, so these energy storage method ranges of application are narrow and small, application scenario is limited, rarely seen have be applied to single energy storage device and be unified into the charge/discharge control method of large-scale energy-storage system, rarely be applied to especially the charge/discharge control method of energy storage device in wind energy turbine set.

Summary of the invention

The objective of the invention is to overcome the shortcoming of wind power forecast prior art aspect accuracy and confidence, propose a kind of wind energy turbine set energy storage device charge/discharge control method.The present invention is based on the wind power prediction error, accurately control energy storage device and discharge and recharge power, the power throughput of energy storage device, can improve the accuracy and confidence of wind power forecast indirectly, to wind energy turbine set short-term prediction error revised of exerting oneself, improve stability and the quality of power supply of electrical network.

The present invention is based on the energy storage device that wind energy turbine set power prediction error controls in wind storage integral system and discharge and recharge power, can carry out for the wind power prediction error under different operating modes power fast and efficiently handles up, and then correction wind power prediction error, realize that wind-powered electricity generation, by the generating curve motion, keeps stable output power to follow the Real-Time Scheduling desired value.

The present invention is that the technical scheme that solve the technical problem employing is:

The present invention monitors the actual P of exerting oneself of wind energy turbine set by the real-time online mode _MkPredict with wind-powered electricity generation the P that exerts oneself _PkVariation, obtain practical relative error e _Pk, and adopt relative error value β=25% as the energy storage power P of handling up _SkAnd the separation of Opportunity awaiting control for linear, the comparator of wind storage integral system energy storage device is according to practical relative error e _PkWith the comparative result of relative error value β, control signal is sent to the controller that gives described energy storage device, control energy storage device by the controller of described energy storage device and discharge and recharge.

The present invention discharges and recharges power by the energy storage device of controlling wind storage integral system, and actual the exerting oneself of wind energy turbine set revised with the different mechanism according to " filling a vacancy flat remaining " of planned dispatching value difference.

" fill a vacancy flat remaining " mechanism is: the practical relative error e that exerts oneself and exert oneself with the wind-powered electricity generation prediction when wind energy turbine set is actual _PkBe defined as " lacking " in the time of<-25%, supply wind-powered electricity generation by the electric discharge of described energy storage device and exert oneself, wind-powered electricity generation is exerted oneself and with the energy storage relative error of comparing with the planned dispatching value with given of exerting oneself, be not less than-25%; The practical relative error e that exerts oneself and exert oneself with wind-powered electricity generation prediction when wind energy turbine set is actual _PkIn the time of>25%, be defined as " remaining ", by the charging of described energy storage device absorption portion wind-powered electricity generation, wind-powered electricity generation exerted oneself and with the energy storage relative error of comparing with the planned dispatching value with given of exerting oneself, be not more than 25%.

Wherein, P _MkFor wind energy turbine set is actual, exert oneself; P _PkFor the wind energy turbine set prediction is exerted oneself; e _PkP exerts oneself for wind energy turbine set is actual _MkPredict with wind-powered electricity generation the P that exerts oneself _PkPractical relative error.

Under ideal state, the maximum throughput power of described energy storage device must be greater than power " vacancy " or " remaining sum " that may occur.Energy storage device electric discharge during power shortage, energy storage device charging during the power surplus, utilize energy storage technology to improve the precision level of wind power forecast.

The present invention can accurately control the power throughput capacity of energy storage device, and using the wind power short-term forecasting value and proposed the needed stored energy capacitance proportioning of compensation wind power prediction error as sample, can be effectively to improve than low-cost or precision and the reliability of " assurance " Short-term Wind Power Prediction.

The present invention stores up by wind the practical relative error e that the comparator of integral system energy storage device will obtain by the real-time online mode _PkWith set-point β=25%, compare, when | e _Pk|≤25%, energy storage is exerted oneself as p _Sk=0, the controller of energy storage device is controlled energy storage device in holding state; As practical relative error e _PkIn the time of<-25%, supply wind-powered electricity generation by the energy storage device electric discharge and exert oneself, it is p that power is sent in the controller control energy storage of energy storage device _Sk=(e _Pk-0.25) Cap, exert oneself wind-powered electricity generation and exert oneself and be not less than-25% with the relative error that the planned dispatching value-the power predicted value is compared with given with energy storage; As practical relative error e _PkIn the time of>25%, the charging of energy storage device absorption portion wind-powered electricity generation, it is p that the controller of energy storage device is controlled the energy storage absorbed power _Sk=(e _Pk-0.25) Cap, exert oneself wind-powered electricity generation and exert oneself and be not more than 25% with the relative error that the planned dispatching value-the power predicted value is compared with given with energy storage.

The present invention obtains the actual P of exerting oneself of wind energy turbine set by the real time on-line monitoring instrument _MkPredict with wind-powered electricity generation the P that exerts oneself _Pk, these two dynamic variable values are sent into to the comparator of energy storage device, obtain practical relative error value e _Pk=(P _Mk-P _Pk)/P _Pk, the comparator of energy storage device compares this error amount and set-point β=25% again, when comparative result is | and e _Pk| in the time of≤25%, the comparator of energy storage device is sent out the controller that control signal is given energy storage device, and the controller of energy storage device is failure to actuate, and now energy storage is exerted oneself as p _Sk=0, energy storage device is in holding state; When comparative result is e _PkIn the time of<-25%, the comparator of energy storage device is sent out the controller that control signal is given energy storage device, the controller action of energy storage device, and it is p that the control energy storage device sends power _Sk=(e _Pk-0.25) Cap, now energy storage device electric discharge is supplied wind-powered electricity generation and is exerted oneself, and wind-powered electricity generation is exerted oneself and with the energy storage relative error of comparing with the planned dispatching value with given of exerting oneself, be not less than-25%; When comparative result is e _PkIn the time of>25%, the comparator of energy storage device is sent out the controller that control signal is given energy storage device, the controller action of energy storage device, and controlling the energy storage device absorbed power is p _Sk=(e _Pk-0.25) Cap, now energy storage device absorption portion wind-powered electricity generation charging, exert oneself wind-powered electricity generation and be not more than 25% with the energy storage relative error of comparing with the planned dispatching value with given of exerting oneself.

The accompanying drawing explanation

Fig. 1 energy storage device " filling a vacancy, it is remaining to put down " principle schematic;

Fig. 2 energy storage device discharges and recharges power control flow schematic diagram;

The energy storage device power control block diagram of handling up in Fig. 3 wind storage integral system;

Fig. 4 stored energy capacitance configuration schematic diagram.

Embodiment

Below in conjunction with the drawings and the specific embodiments, the present invention will be further described.

Energy storage device in the present invention " is filled a vacancy flat remaining ", and principle as shown in Figure 1.

At first the present invention monitors the actual situation of exerting oneself of wind-powered electricity generation, by the actual P that exerts oneself of wind energy turbine set _MkPredict with wind-powered electricity generation the P that exerts oneself _PkCompare, with Relative Error value β, judge whether energy storage device exerts oneself, adopt relative error value β=25% to gulp down, tell power P as energy storage _SkAnd the separation of Opportunity awaiting control for linear, with the situation of specifically exerting oneself of " filling a vacancy flat remaining " mechanism control energy storage link.Work as practical relative error | e _Pk|≤25%, energy storage is exerted oneself as p _Sk=0, energy storage device is in holding state; As practical relative error e _PkIn the time of<-25%, be defined as " lacking ", supply wind-powered electricity generation by the energy storage device electric discharge and exert oneself, wind-powered electricity generation is exerted oneself, and the relative error that the planned dispatching value-the power predicted value is compared that exert oneself with energy storage and with given is not less than-25%; As practical relative error e _PkIn the time of>25%, be defined as " remaining ", the charging of energy storage device absorption portion wind-powered electricity generation, wind-powered electricity generation is exerted oneself, and the relative error that the planned dispatching value-the power predicted value is compared that exert oneself with energy storage and with given is not more than 25%.

Fig. 2 is that energy storage device discharges and recharges power control flow schematic diagram.As shown in Figure 2, actual the exerting oneself of Real-Time Monitoring wind energy turbine set predicts with wind-powered electricity generation the practical relative error e exerted oneself _Pk, as practical relative error e _PkIn the time of<-25%, the energy storage device electric discharge is supplied wind-powered electricity generation and is exerted oneself, and wind-powered electricity generation is exerted oneself and with energy storage, exert oneself and be not less than-25% with the relative error that the planned dispatching value-the power predicted value is compared with given, and energy storing and electricity generating is exerted oneself as p _Sk=(e _Pk-0.25) Cap, energy storage device is in discharge condition; As practical relative error e _PkIn the time of>25%, the charging of energy storage absorption portion wind-powered electricity generation, exert oneself wind-powered electricity generation and exert oneself and be not more than 25% with the relative error that the planned dispatching value-the power predicted value is compared with given with energy storage, and energy storing and electricity generating is exerted oneself as p _Sk=(e _Pk-0.25) Cap, energy storage device is in charged state.

The present invention adopts the prerequisite of rational capacity of energy storing device configuration as optimization system function technical indicator, and has considered the problem of following two aspects:

The total capacity of whole energy storage device.Less energy storage total capacity is difficult to guarantee the wind-powered electricity generation prediction error of exerting oneself is carried out to the universe correction, and although the target of exerting oneself is easily reached in the configuration of excessive energy storage total capacity, but can cause on the once input of energy storage device larger, the optimization that is difficult to reach the systematic economy performance.

The capacity ratio of the energy storage device that energy storage device is inner dissimilar.At energy storage device, in the capacity ratio of inner dissimilar energy storage device, if lithium battery homenergic type energy storage device capacity is too small, easily cause the energy type energy storage device " to overcharge deeply and put " continually, the economic index of its life cycle management sharply reduces; In like manner, if the capacity configuration of ultracapacitor homenergic type energy storage device is too low, easily cause the quick component in the error distribution to be difficult to by the full width correction.

Concrete, when | e _Pk|≤25%, energy storage is exerted oneself as p _Sk=0, the energy storage device standby; Work as e _Pk>25%, energy storage is exerted oneself as p _Sk=(e _Pk-0.25) Cap, the energy storage device charging; Work as e _Pk<-25%, energy storage is exerted oneself as p _Sk=(e _Pk-0.25) Cap, the energy storage device electric discharge.

Concrete, target for the energy-storage system power configuration computing formula that improves wind-powered electricity generation economic dispatch plan confidence level is

Wherein,

The actual wind power short-term forecasting sequential value that is greater than 25% for power prediction relative error absolute value,

For with

The envelope sequence value of corresponding actual wind power value, the wind power short-term forecasting sequential value that virtual predicated error equals 25%, predicated error equals 25% wind power short-term forecasting sequential value and is $p_{\mathrm{pk}}^{\&CenterDot;}=p_{\mathrm{mk}}\&PlusMinus;0.25\&CenterDot;\mathrm{Cap},$ Wherein, P _MkFor wind energy turbine set is actual, exert oneself.

Further, in order to make energy storage device, can realize the compensation to the power prediction error with certain probability, energy storage device be take the rated power continuous output time as t, and formula is as follows:

$t=k\&CenterDot;\frac{{\mathrm{<figure-callout\; id="0"\; label="s"\; filenames="HDA00003202683600011.png,HDA00003202683600012.png"\; state="\{\{state\}\}">s</figure-callout>}}_0+\max \left(\right|{\mathrm{<figure-callout\; id="1"\; label="s"\; filenames="HDA00003202683600011.png"\; state="\{\{state\}\}">s</figure-callout>}}_1|,|{\mathrm{<figure-callout\; id="1"\; label="s"\; filenames="HDA00003202683600011.png"\; state="\{\{state\}\}">s</figure-callout>}}_1+s_2|,|{\mathrm{<figure-callout\; id="1"\; label="s"\; filenames="HDA00003202683600011.png"\; state="\{\{state\}\}">s</figure-callout>}}_1+s_2+{\mathrm{<figure-callout\; id="3"\; label="s"\; filenames="HDA00003202683600011.png"\; state="\{\{state\}\}">s</figure-callout>}}_3|,\&CenterDot;\&CenterDot;\&CenterDot;|\underset{i=1}{\overset{n}{\mathrm{\&Sigma;}}}{s}_i\left|\right)}{P_{\mathrm{se}}}$

Wherein, s ₀For the least residue electric weight determined by the electric physical property of energy storage device; s ₁, s ₂... in certain computing cycle, usually getting 1 day, 96 periods is a computing cycle, the discharge electricity amount of energy storage when each wind power vacancy or remaining sum period need " filling a vacancy ", for on the occasion of, or the charge capacity of the energy storage while needing " flat remaining ", be negative value; p _SeDischarge and recharge power for energy storage device is specified, the general same p of value _sN is the period sum that needs " filling a vacancy flat remaining " in research cycle; K is safety factor, and its value should reflect the statistics power of wind power prediction error, has determined that energy storage device can realize its " fill a vacancy flat remaining " target with great probability simultaneously.

Further, the purpose of according to " filling a vacancy flat remaining " mechanism, the wind power prediction error being revised for reaching energy storage device, various energy storage devices need to have certain capacity requirement, and need to realize by corresponding controlling organization, Figure 3 shows that configuration and control method thereof to stored energy capacitance.

As shown in Figure 3, at first by the real-time online mode, obtain the actual P of exerting oneself of wind energy turbine set _MkPredict with wind-powered electricity generation the P that exerts oneself _Pk, these two dynamic variable values are sent into to the comparator of energy storage device, its output valve is practical relative error value e _Pk=(P _Mk-P _Pk)/P _PkThen the comparator of energy storage device compares this error amount and set-point β=25%, obtain three kinds of comparative results, the comparator of energy storage device sends out according to different comparative results the controller that control signal is given energy storage device, the controller action of energy storage device is in energy storage device and make it in 3 kinds of operating states, and details are as follows for this section process:

1. working as comparative result is | e _Pk| in the time of≤25%, the comparator of energy storage device is sent out the controller that control signal is given energy storage device, and the controller of energy storage device is failure to actuate, and now energy storage is exerted oneself as p _Sk=0, energy storage device is in holding state;

2. working as comparative result is e _PkIn the time of<-25%, the comparator of energy storage device is sent out control signal and is given the energy storage device controller, the controller action of energy storage device, and controlling the energy storage device power that spues is p _Sk=(e _Pk-0.25) Cap, now energy storage device electric discharge is supplied wind-powered electricity generation and is exerted oneself, and wind-powered electricity generation is exerted oneself and with energy storage, exert oneself and be not less than-25% with the relative error that the planned dispatching value-the power predicted value is compared with given;

3. working as comparative result is e _PkIn the time of>25%, the comparator of energy storage device is sent out control signal and is given the energy storage device controller, the controller action of energy storage device, and it is p that the control energy storage device is swallowed power _Sk=(e _Pk-0.25) Cap, now energy storage device absorption portion wind-powered electricity generation charging, exert oneself wind-powered electricity generation and exert oneself and be not more than 25% with the relative error that the planned dispatching value-the power predicted value is compared with given with energy storage.Finally, wind-powered electricity generation is exerted oneself and the energy storage gross power that sum is the wind energy turbine set injected system of exerting oneself.

Meritorious power curve while having two envelopes to represent predicated error ± 25% in Fig. 4, one in order to dope force curve, another is actual power curve, when occurring that prediction curve is above envelope, predicted value is bigger than normal, i.e. e _Pk>25%, the diagonal line hatches zone, energy storage device is in discharge condition; When occurring that prediction curve is below envelope, predicted value is less than normal, i.e. e _Pk<-25%, the grid shadow region, energy storage device is in charged state; In all the other situations, energy storage device is in holding state.

Claims (3)

1. a wind energy turbine set energy storage device charge/discharge control method, is characterized in that, described charge/discharge control method is based on wind energy turbine set power prediction error, and the energy storage device of controlling in wind storage integral system discharges and recharges power; Monitor the actual P of exerting oneself of wind energy turbine set by the real-time online mode _MkPredict with wind-powered electricity generation the P that exerts oneself _PkVariation, obtain practical relative error e _Pk, and adopt relative error value β=25% as the energy storage power P of handling up _SkAnd the separation of Opportunity awaiting control for linear, the comparator of described energy storage device is according to actual absolute error e _PkWith the comparative result of relative error value β, control signal is sent to the controller that gives energy storage device, control energy storage device by the controller of energy storage device and discharge and recharge.

2. according to wind energy turbine set energy storage device charge/discharge control method claimed in claim 1, it is characterized in that, described real-time online mode is monitored the actual P of exerting oneself of wind energy turbine set _MkPredict with wind-powered electricity generation the P that exerts oneself _PkPractical relative error e _Pk, as practical relative error e _PkIn the time of<-25%, energy storage device electric discharge is supplied wind-powered electricity generation and is exerted oneself, and wind-powered electricity generation is exerted oneself and with the energy storage sum of exerting oneself, with the given relative error that the planned dispatching value-the power predicted value is compared, be not less than-25%, and energy storing and electricity generating is exerted oneself as p _Sk=(e _Pk-0.25) Cap, energy storage device is in discharge condition; As practical relative error e _PkIn the time of>25%, the charging of energy storage absorption portion wind-powered electricity generation, wind-powered electricity generation is exerted oneself, and the relative error that the planned dispatching value-the power predicted value is compared that exert oneself with energy storage and with given is not more than 25%, and energy storing and electricity generating is exerted oneself as p _Sk=(e _Pk-0.25) Cap, energy storage device is in charged state.

3. according to the described wind energy turbine set energy storage device of claim 1 or 2 charge/discharge control method, it is characterized in that, the step of described charge/discharge control method is:

(1) obtain the actual P of exerting oneself of wind energy turbine set by the real time on-line monitoring mode _MkPredict with wind-powered electricity generation the P that exerts oneself _Pk, these two dynamic variable values are sent into to the comparator of energy storage device, output practical relative error value e _Pk=(P _Mk-P _Pk)/P _Pk

(2) comparator of energy storage device compares this error amount and set-point β=25%, obtains three kinds of comparative results:

1) when comparative result be | e _Pk| in the time of≤25%, the comparator of energy storage device is sent out the controller that control signal is given energy storage device, and the controller of energy storage device is failure to actuate, and now energy storage is exerted oneself as p _Sk=0, energy storage device is in holding state;

2) when comparative result be e _PkIn the time of<-25%, the comparator of energy storage device is sent out the controller that control signal is given energy storage device, the controller action of energy storage device, and controlling the energy storage device power that spues is p _Sk=(e _Pk-0.25) Cap, now energy storage device electric discharge is supplied wind-powered electricity generation and is exerted oneself, and wind-powered electricity generation is exerted oneself and with energy storage, exert oneself and be not less than-25% with the relative error that the planned dispatching value-the power predicted value is compared with given;

3) when comparative result be e _PkIn the time of>25%, the comparator of energy storage device is sent out the controller that control signal is given energy storage device, the controller action of energy storage device, and it is p that the control energy storage device is swallowed power _Sk=(e _Pk-0.25) Cap, now energy storage device absorption portion wind-powered electricity generation charging, exert oneself wind-powered electricity generation and exert oneself and be not more than 25% with the relative error that the planned dispatching value-the power predicted value is compared with given with energy storage.

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