CN103997045B - The collocation method of Reactive Compensation in Wind Farm and system - Google Patents

Abstract

The present invention provides the collocation method of a kind of Reactive Compensation in Wind Farm, comprises the steps: to gather the electric data of wind energy turbine set；According to described electric data and default wind energy turbine set electrical simulation model, measure maximum capacitive reactive power and the maximum inductive reactive power of wind energy turbine set；According to the reactive power regulating power of described electric data, maximum capacitive reactive power, maximum inductive reactive power and blower fan, determine the type of reactive power compensator and calculate the reactive compensation capacity of reactive power compensator；Wherein, described reactive power compensator includes shunt reactor, shnt capacitor and/or SVG device；The reactive power compensator being configured with described reactive compensation capacity is installed in the also site of described wind energy turbine set.The present invention also provides for the system of correspondence, can determine type and the capacity of reactive-load compensation quickly and easily.

Description

The collocation method of Reactive Compensation in Wind Farm and system

Technical field

The present invention relates to technical field of wind power, particularly relate to the collocation method of a kind of Reactive Compensation in Wind Farm, and the configuration system of a kind of Reactive Compensation in Wind Farm.

Background technology

Along with the carrying out of global energy crisis, new forms of energy especially wind-powered electricity generation quickly grows in the whole world, and marine wind electric field, relative to land wind-powered electricity generation, has wind-resources good, and annual electricity generating capacity is high, takies the advantages such as land is few, quickly grows in recent years.

In the research of wind energy turbine set at sea and design, reactive-load compensation is a very important problem, directly influences power factor (PF) and voltage levvl that wind energy turbine set is examined, and wind energy turbine set reactive power support ability.For the idle allocation problem of marine wind electric field, including the type selecting of reactive power compensator, capacity is chosen, and position selects, and lacks relevant ripe achievement in research and practical experience the most both at home and abroad, does not also have authoritative method and conclusion at design aspect.

For current engineering practice, because offshore platform cost is high and limited space, the reactive power compensator of wind energy turbine set is placed at the wind farm grid-connected point of land by most wind energy turbine set, so arranges to be equally beneficial for the fast reaction to examination point.Reactive power compensator type is depending on the electrical network grid-connected requirement to wind energy turbine set, the most typically select SVG (Static Var Generator, static reacance generator) more, because SVG adjustable range is big, and real-time is good, it is possible to quickly floating voltage and the change of reactive power, compensation effect is good, but the SVG of equivalent capability compares other compensation ways costly, and floor space is bigger simultaneously.For the control of compensation capacity, the electrical network the to be combined grid-connected requirement to wind energy turbine set, reactive power compensator type and the selection of position, consider, by being calculated capacity selected value.The capacity of reactive-load compensation can directly influence the economy of project, general the most comparatively laborious to the method for Reactive Compensation in Wind Farm capacity, amount of calculation is bigger than normal, and not necessarily practical, needs type and the capacity searching out a kind of correct and easy method to determine Reactive Compensation in Wind Farm.

Summary of the invention

Based on this, the present invention provides reactive compensation configuration method and the system of a kind of wind energy turbine set, can determine type and the capacity of reactive-load compensation quickly and easily.

The collocation method of a kind of Reactive Compensation in Wind Farm, comprises the steps:

Gather the electric data of wind energy turbine set；

According to described electric data and default wind energy turbine set electrical simulation model, measure maximum capacitive reactive power and the maximum inductive reactive power of wind energy turbine set；

According to the reactive power regulating power of described electric data, maximum capacitive reactive power, maximum inductive reactive power and blower fan, determine the type of reactive power compensator and calculate the reactive compensation capacity of reactive power compensator；Wherein, described reactive power compensator includes shunt reactor, shnt capacitor and/or SVG device；

The reactive power compensator being configured with described reactive compensation capacity is installed in the also site of described wind energy turbine set.

A kind of reactive-load compensation configuration system of wind energy turbine set, including reactive power compensator, described reactive power compensator includes shunt reactor, shnt capacitor and/or SVG device, also includes:

Acquisition module, for gathering the electric data of wind energy turbine set；

Measurement module, for according to described electric data and default wind energy turbine set electrical simulation model, measuring maximum capacitive reactive power and the maximum inductive reactive power of wind energy turbine set；

Computing module, for the reactive power regulating power according to described electric data, maximum capacitive reactive power, maximum inductive reactive power and blower fan, determines reactive power compensator type and calculates the reactive compensation capacity of reactive power compensator；

Described reactive power compensator is configured with described reactive compensation capacity, and is arranged on the also site of described wind energy turbine set.

The collocation method of above-mentioned Reactive Compensation in Wind Farm and system, by maximum capacitive reactive power and the maximum inductive reactive power of detection wind energy turbine set, reactive power regulating power further according to electric data, maximum capacitive reactive power, maximum inductive reactive power and blower fan, determine reactive power compensator type, calculating the reactive compensation capacity of reactive power compensator, the calculating process of reactive compensation capacity is the quickest；Using shunt reactor, shnt capacitor or SVG device as reactive power compensator, on the premise of meeting wind farm grid-connected condition, use the most jumbo reactor, space the most more saved by reactor so that the control program of reactive-load compensation is more economically.

Accompanying drawing explanation

Fig. 1 is the reactive compensation configuration method schematic flow sheet in one embodiment of wind energy turbine set of the present invention.

Fig. 2 is the reactive-load compensation configuration system structural representation in one embodiment of wind energy turbine set of the present invention.

Detailed description of the invention

Below in conjunction with embodiment and accompanying drawing, the present invention is described in further detail, but embodiments of the present invention are not limited to this.

As it is shown in figure 1, be the reactive compensation configuration method schematic flow sheet in one embodiment of wind energy turbine set of the present invention, comprise the steps:

S11, the electric data of collection wind energy turbine set；

S12, according to described electric data and default wind energy turbine set electrical simulation model, measure maximum capacitive reactive power and the maximum inductive reactive power of wind energy turbine set；

S13, reactive power regulating power according to described electric data, maximum capacitive reactive power, maximum inductive reactive power and blower fan, determine reactive power compensator type and calculate the reactive compensation capacity of reactive power compensator；Wherein, described reactive power compensator includes shunt reactor, shnt capacitor and/or SVG device；

S14, described wind energy turbine set and site install configure described reactive compensation capacity reactive power compensator；

In the present embodiment, by maximum capacitive reactive power and the maximum inductive reactive power of detection wind energy turbine set, reactive power regulating power further according to electric data, maximum capacitive reactive power, maximum inductive reactive power and blower fan, calculating the reactive compensation capacity of reactive power compensator, the calculating process of reactive compensation capacity is the quickest；Use reactor and SVG device as reactive power compensator, on the premise of meeting wind farm grid-connected condition, the most jumbo reactor (or capacitor), reactor (or capacitor) is used the most more to save space so that the control program of reactive-load compensation is more economically.

In a preferred embodiment, described according to described electric data with the wind energy turbine set electrical simulation model preset, the step measuring the maximum capacitive reactive power of wind energy turbine set and maximum inductive reactive power includes:

According to described wind energy turbine set electrical simulation model, make P_WT=0, Q_WT=0, U=U_max, it is thus achieved that described maximum capacitive reactive power；Wherein, P_WTThe active power sent for blower fan, Q_WTThe reactive power sent for blower fan, U is grid-connected voltage, U_maxThe grid-connected voltage of maximum for default wind energy turbine set；

According to described wind energy turbine set electrical simulation model, make P_WT=P_N, U=U_min, it is thus achieved that described maximum capacitive reactive power；Wherein, P_NFor the specified active power of blower fan, U_minThe grid-connected voltage of minimum for default wind energy turbine set；

In the present embodiment, when wind energy turbine set is carried out the control of reactive power compensating, there are following two assumed conditions:

Think that in the calculating of capacity of reactive power compensation device wind power plant operation mode is constant, do not consider the failure operation state of wind energy turbine set, i.e. electric capacity and the reactance value of the equivalence in wind energy turbine set are constant；

Consider that wind energy turbine set to run builtin voltage loss less, send in analytical calculation reactive power and thinks when consuming that voltage levvl is the same with grid-connected voltage in wind field.

It may thus be appreciated that, do not consider reactive power compensator and blower fan idle exert oneself in the case of, reactive power total amount Q that wind-powered electricity generation place sends is solely dependent upon the P that exerts oneself (wind energy turbine set output electric current I) of grid-connected voltage U and wind energy turbine set, wherein square being directly proportional of the charge power Q of cable and static exciter reactive power and grid-connected voltage U, the lagging reactive power that cable, transformer leakage reactance part send and wind energy turbine set output electric current I square are directly proportional.

The capacitive reactive power of wind energy turbine set can be:

Q_WFC=-Q_CL-Q_TRL-Q_TRB+Q_CC-Q_MCR+Q_MSC±Q_WT±Q_SVG；

Wherein Q_WFCFor the lagging reactive power that wind energy turbine set is total, Q_CLThe lagging reactive power sent for cable reactance, Q_TRLThe lagging reactive power sent for transformer leakage reactance, Q_TRBThe lagging reactive power sent by static exciter reactance, Q_CCFor the charge power (reactive power of capacitive) sent of cable, Q in wind field_MCRThe lagging reactive power sent by the reactor installed, Q_MSCThe capacitive reactive power sent for opening-closing capacitor bank, Q_WTThe lagging reactive power sent for blower fan, Q_SVGThe lagging reactive power sent for SVG, owing to blower fan and SVG can send capacitive and the reactive power of perception, so Q_WTAnd Q_SVGBefore can just can bear.

In the formula of the capacitive reactive power of above-mentioned wind energy turbine set, Q_CLAnd Q_TRLSquare I with electric current²It is directly proportional, Q_TRB、Q_MCR、Q_MSCAnd Q_CCSquare U with grid-connected voltage²It is directly proportional, Q_WTAnd Q_SVGCan regulate with apparent wind electric field reactive voltage control system (AVC), send corresponding reactive power, with grid-connected voltage U and wind field electric current I without direct relation.

For marine wind electric field, owing to there is substantial amounts of submarine cable in wind energy turbine set, the charge power of submarine cable is the biggest, more than wind energy turbine set inner cable and the equivalent reactance of transformer, so marine wind electric field entirety presents capacitive load, according to integrated wind plant reactive power requirement, need to install additional suitable capacity can switching reactor to balance too much capacitive reactive power Q.

For land wind energy turbine set, owing to wind energy turbine set inside cable is less, during wind energy turbine set zero load, capacitive reactive power is more, increase along with output of wind electric field, the lagging reactive power sent increases, make the reactive power of wind energy turbine set slowly in perception, so land wind energy turbine set may present inductive load character, if land wind energy turbine set is overall in perception, switched shunts can be installed additional to balance unnecessary lagging reactive power, if land wind energy turbine set is overall in capacitive, can install additional can switching Reactor banks to balance unnecessary capacitive reactive power.

The reactive power of wind energy turbine set can be divided into two class sources: a class is square proportional reactive power source or the load with grid-connected voltage, distribution capacity such as cable, the excitation reactance of transformer, and the switched capacitors of parallel connection and reactor, become 1 class load or burden without work by this type load.One class is square reactive power source being directly proportional or the load to electric current, such as the reactance of cable, the leakage reactance of transformer, this type load becomes 2 class load or burden without work.

The lagging reactive power making 1 class load or burden without work send is Q_C(U), there is following computing formula:

Q_C(U)=Q_CC-Q_MCR-Q_TRB=wCU²-U²/wL_MCR-B_TU²=(wC-B_T-1/wL_MCR)·U²；

Wherein, Q_C(U) for the lagging reactive power sent with square proportional reactive power source or the load of grid-connected voltage, w is angular frequency, and C is the capacity of wind energy turbine set, and U is grid-connected voltage, L_MCRFor the reactive compensation capacity of shunt reactor, B_TFor susceptance, L_CFor cable reactance value, L_TRFor transformer reactance value, P_WFThe active power sent for wind energy turbine set, Q_WFThe reactive power sent for wind energy turbine set；

As a example by marine wind electric field, owing to marine wind electric field submarine cable is more, marine wind electric field is overall in capacitive load, has wC ＞ B_T+1/wL_MCR, it is possible to know the capacitive reactive power Q that such load or burden without work sends_C(U) it is increasing function at U ∈ (0 ,+∞), i.e. works as U=U_maxTime 1 class load or burden without work to send capacitive reactive power maximum, work as U=U_minTime 1 class reactive power load to send capacitive reactive power minimum.

The lagging reactive power making 2 class load or burden without work send is Q_L(I), there is expression formula:

Q_L(I)=(wL_C+wL_TR)·I²=(wL_C+wL_TR)·(P_WF ²+Q_WF ²)/U²；

Can be known by above-mentioned formula, 2 class load or burden without work are completely sent out in wind energy turbine set, (P=P when grid-connected voltage is minimum_max, U=U_min) lagging reactive power that sends is maximum, unloaded at wind field, grid-connected voltage is up to P_WT=0, Q_WT=0, U=U_max, the lagging reactive power sent is minimum.

Summary is described, and the capacitive reactive power that whole marine wind electric field sends has Q_WF=Q_C(U)-Q_L(I), by above-mentioned analysis it is recognised that when wind energy turbine set zero load, blower fan does not send power, during grid-connected voltage maximum, i.e. P_WT=0, Q_WT=0, U=U_max, it is maximum that wind energy turbine set 1 class load or burden without work sends capacitive reactive power, and it is minimum that 2 class load or burden without work send lagging reactive power, so the capacitive reactive power that now wind energy turbine set sends is maximum, is designated as Q_Cmax.In like manner understand, when wind energy turbine set is fully loaded with, when grid-connected voltage is minimum, i.e. P=P_max, U=U_min, it is maximum that wind energy turbine set sends lagging reactive power, is designated as Q_Lmax.More than analyze, equally applicable for land wind energy turbine set.

Thus, it can be known that work as P_WT=0, Q_WT=0, U=U_maxTime, the maximum capacitive reactive power of available wind energy turbine set；Work as P_WT=P_N, U=U_minTime, the maximum inductive reactive power of available wind energy turbine set.

In a preferred embodiment, when blower fan does not possess reactive power regulating power,

If Q_Cmax＞ Q_Lmax, according to reactive compensation capacity and the reactive compensation capacity of SVG device of the following formula described shunt reactor of calculating:

If Q_Cmax=Q_Lmax, the reactive compensation capacity of SVG device: C is calculated according to following formula_SVG=Q_Cmax；

If Q_Cmax＜ Q_Lmax, according to reactive compensation capacity and the reactive compensation capacity of SVG device of following formula calculating Shunt Capacitor Unit:

Wherein, L_MCRFor the reactive compensation capacity of shunt reactor, w is angular frequency, Q_CmaxFor described maximum capacitive reactive power, Q_LmaxFor described maximum inductive reactive power, C_SVGFor the reactive compensation capacity of SVG device, C_MSCReactive compensation capacity for Shunt Capacitor Unit；

When blower fan possesses reactive power regulating power, according to the reactive compensation capacity of following formula calculating reactive power compensator:

Wherein, L_MCRFor the reactive compensation capacity of shunt reactor, C_SVGReactive compensation capacity for SVG device；

In the present embodiment, when obtaining the maximum capacitive reactive power of wind energy turbine set and maximum inductive reactive power, it may be determined that reactive power compensator type, calculate the reactive compensation capacity of reactive power compensator, be divided into the following two kinds situation:

When not considering the reactive power regulating power of blower fan, as a example by marine wind electric field, the reactive power regulation of wind field only regulates by MSR (Mechanical Switching Reactor, machinery switching reactor) and SVG, and the most only SVG has corresponding Reactive-power control ability.The filled SVG of wind field should be able to should be able to be fully compensated wind energy turbine set and reactive power that outlet line is sent when wind energy turbine set sends maximum capacitive or lagging reactive power, i.e. Q=0,Then have:

Above formula is solved, obtains the capacity C of SVG_SVGCapacity L with shunt reactor_MCR:

As seen from the above, the effect of reactor is that wind energy turbine set load character is adjusted equilibrium, if the equilibrium of wind field load character, has Q_Cmax-Q_Lmax=0, then parallel reactance L_MCR=∞ now C_SVG=Q_Cmax=Q_Lmax, i.e. need not to install switching reactor in parallel, the SVG capacity of installation is the capacitive that sends of wind energy turbine set and perception peak power.In like manner, if for land wind energy turbine set, if there being Q_Cmax＜ Q_Lmax, then opening-closing capacitor bank in parallel should be installed, have:

Above formula is solved, obtains the capacity C of SVG_SVGCapacity C with Shunt Capacitor Unit_MSC:

No matter install parallel reactance or shunt capacitance additional, be provided to Equilibrium Wind load, reduce the capacity of SVG；In two kinds of compensation ways, the capacity expression of SVG is just as.

In order to ensure meeting the grid-connected requirement of wind field, can leave allowance to reactive-load compensation configuration, reactance value capacity can be configured by calculated value, 110% the 120% of the desirable calculated value of capacity of SVG.

When considering the Reactive-power control ability of blower fan, according to GBT19963-2011 " wind energy turbine set accesses power system technology regulation ", specify grid-connected wind field blower fan should possess power factor dynamic adjustable ability, i.e.-0.312P in the range of advanced 0.95～delayed 0.95_WT≤Q_WT≤+0.312P_WT。

Because blower fan possesses the ability dynamically regulating reactive power, perception or capacitive reactive power can be sent according to controlling requirement, be equivalent to the function of SVG.When, after the Reactive-power control ability considering blower fan, increasing the regulating power of the reactive power of wind energy turbine set, simultaneously in terms of reactive-load compensation configuration, the biggest cost can be saved according to calculating the installed capacity suitably reducing SVG.But the reactive power regulating power of blower fan only could be considered when blower fan is incorporated into the power networks, randomness due to wind-resources, wind energy turbine set there may be some Fans at run duration and can not generate electricity by way of merging two or more grid systems for some reason operation, and now the reactive power regulating power of wind energy turbine set is also restricted.

Owing to grid-connected blower fan has possessed the idle dynamic regulating power of SVG, so the capacity of SVG can according to circumstances be reduced, from the angle of economy, use the scheme that cost is minimum to use reactor as the capital equipment compensated as far as possible, i.e. use jumbo reactor arrangement.

When considering wind field zero load, blower fan off-grid, take P_WT=0, Q_WT=0, U=U_max, the capacitive reactive power Q that wind field maximum sends can be obtained_Cmax.Now consider to use shunt reactor to compensate whole capacitive reactive power Q_Cmax。

Then have:

Can be by I_C=(wC_C-B_T)U_maxSubstitute into, then have:

Therefore, the capacity of the electrical equipment in parallel obtaining installation is:

L_MCR=1/w (wC_C-B_T)·(wC_C-B_T-wL_TR-wL_C)。

When blower fan is incorporated into the power networks, can inject to grid power and electric current, add the output of wind field lagging reactive power, but being incorporated to due to blower fan, also make wind field add corresponding blower fan Reactive-power control ability, the increase of some or all of lagging reactive power can be offset.Need to blower fan grid-connected after, the change of wind field reactive power calculates.

By fan operation rated power calculate, increase a Fans grid-connected after, wind energy turbine set increase capacitive reactive power deposit have:

Wherein, U is grid-connected voltage, and according to power supply quality requirement, typically i.e. can not have more than 10% for the voltage drop of transmission line in wind field:

Therefore capacitive reactive power deposit is:

So after in wind field, increase by one Fans is incorporated into the power networks, it practice, what the deposit of the capacitive reactive power of wind field was to increase.Mean when the grid-connected number of units of the blower fan in wind field gradually increases, the increase of the lagging reactive power that the electric current of wind energy turbine set output increases and causes, but the increments of lagging reactive power can be dissolved by the reactive power regulating power of blower fan, and grid-connected blower fan number of units is the most, the capacitive reactive power deposit of whole wind field will be the biggest.

Owing to the capacity of shunt reactor is L_MCR=1/w (wC_C-B_T)·(wC_C-B_T-wL_TR-wL_C), how the most grid-connected voltage changes, and the lagging reactive power that shunt reactor is issued can compensate reactive power that the distribution capacity of power down cable brings (including the consumption of the lagging reactive power that cable charge power and charge power brought).

So the most grid-connected voltage is how many, after the reactor installing respective volume additional, the Reactive-power control ability of blower fan can regulate the reactive power of whole wind field, makes the reactive power sent of whole wind field meet grid-connected requirement.Therefore consider power of fan factor in the range of advanced 0.95～delayed 0.95 dynamically can timing, only need to install shunt reactor additional and just can meet wind farm grid-connected regulation requirement, it is not necessary to install extra SVG device additional.In the case of Gai, obtain the capacity C of SVG_SVGCapacity L with shunt reactor_MCRHave

Actually the regulating power of blower fan tend not to meet grid-connected require regulation under any operating mode, power factor is the most adjustable in the range of advanced 0.95～delayed 0.95, so the capacity of SVG can the most suitably be increased, such as the capacity of SVG is set to 10% (or reactance value takes the 90% of calculated value, the 20% of the anti-calculated value of SVG capacity power taking) of reactor.

As in figure 2 it is shown, be the reactive-load compensation configuration system structural representation in one embodiment of wind energy turbine set of the present invention, wind energy turbine set includes that reactive power compensator 24, described reactive power compensator include shunt reactor, shnt capacitor and/or SVG device, also include:

Acquisition module 21, for gathering the electric data of wind energy turbine set；

Measurement module 22, for according to described electric data and default wind energy turbine set electrical simulation model, measuring maximum capacitive reactive power and the maximum inductive reactive power of wind energy turbine set；

Computing module 23, for the reactive power regulating power according to described electric data, maximum capacitive reactive power, maximum inductive reactive power and blower fan, determines reactive power compensator type and calculates the reactive compensation capacity of reactive power compensator；

Described reactive power compensator is configured with described reactive compensation capacity, and is arranged on the also site of described wind energy turbine set.

In the present embodiment, by maximum capacitive reactive power and the maximum inductive reactive power of detection wind energy turbine set, reactive power regulating power further according to electric data, maximum capacitive reactive power, maximum inductive reactive power and blower fan, calculating the reactive compensation capacity of reactive power compensator, the calculating process of reactive compensation capacity is the quickest；Use reactor and SVG device as reactive power compensator, on the premise of meeting wind farm grid-connected condition, the most jumbo reactor (or capacitor), reactor (or capacitor) is used the most more to save space so that the control program of reactive-load compensation is more economically.

In a preferred embodiment, described measurement module 22 is additionally operable to:

According to described wind energy turbine set electrical simulation model, make P_WT=0, Q_WT=0, U=U_max, it is thus achieved that described maximum capacitive reactive power；Wherein, P_WTThe active power sent for blower fan, Q_WTThe reactive power sent for blower fan, U is grid-connected voltage, U_maxThe grid-connected voltage of maximum for default wind energy turbine set；

According to described wind energy turbine set electrical simulation model, make P_WT=P_N, U=U_min, it is thus achieved that described maximum capacitive reactive power；Wherein, P_NFor the specified active power of blower fan, U_minThe grid-connected voltage of minimum for default wind energy turbine set.

In the present embodiment, when wind energy turbine set is carried out the control of reactive power compensating, there are following two assumed conditions:

Think that in the calculating of capacity of reactive power compensation device wind power plant operation mode is constant, do not consider the failure operation state of wind energy turbine set, i.e. electric capacity and the reactance value of the equivalence in wind energy turbine set are constant；

Consider that wind energy turbine set to run builtin voltage loss less, send in analytical calculation reactive power and thinks when consuming that voltage levvl is the same with grid-connected voltage in wind field.

It may thus be appreciated that, do not consider reactive power compensator and blower fan idle exert oneself in the case of, reactive power total amount Q that wind-powered electricity generation place sends is solely dependent upon the P that exerts oneself (wind energy turbine set output electric current I) of grid-connected voltage U and wind energy turbine set, wherein square being directly proportional of the charge power Q of cable and static exciter reactive power and grid-connected voltage U, the lagging reactive power that cable, transformer leakage reactance part send and wind energy turbine set output electric current I square are directly proportional.

The capacitive reactive power of wind energy turbine set can be:

Q_WFC=-Q_CL-Q_TRL-Q_TRB+Q_CC-Q_MCR+Q_MSC±Q_WT±Q_SVG；

Wherein Q_WFCFor the lagging reactive power that wind energy turbine set is total, Q_CLThe lagging reactive power sent for cable reactance, Q_TRLThe lagging reactive power sent for transformer leakage reactance, Q_TRBThe lagging reactive power sent by static exciter reactance, Q_CCFor the charge power (reactive power of capacitive) sent of cable, Q in wind field_MCRThe lagging reactive power sent by the reactor installed, Q_MSCThe capacitive reactive power sent for opening-closing capacitor bank, Q_WTThe lagging reactive power sent for blower fan, Q_SVGThe lagging reactive power sent for SVG, owing to blower fan and SVG can send capacitive and the reactive power of perception, so Q_WTAnd Q_SVGBefore can just can bear.

In the formula of the capacitive reactive power of above-mentioned wind energy turbine set, Q_CLAnd Q_TRLSquare I with electric current²It is directly proportional, Q_TRB、Q_MCR、Q_MSCAnd Q_CCSquare U with grid-connected voltage²It is directly proportional, Q_WTAnd Q_SVGCan regulate with apparent wind electric field reactive voltage control system (AVC), send corresponding reactive power, with grid-connected voltage U and wind field electric current I without direct relation.

For marine wind electric field, owing to there is substantial amounts of submarine cable in wind energy turbine set, the charge power of submarine cable is the biggest, more than wind energy turbine set inner cable and the equivalent reactance of transformer, so marine wind electric field entirety presents capacitive load, according to integrated wind plant reactive power requirement, need to install additional suitable capacity can switching reactor to balance too much capacitive reactive power Q.

For land wind energy turbine set, owing to wind energy turbine set inside cable is less, during wind energy turbine set zero load, capacitive reactive power is more, increase along with output of wind electric field, the lagging reactive power sent increases, make the reactive power of wind energy turbine set slowly in perception, so land wind energy turbine set may present inductive load character, if land wind energy turbine set is overall in perception, switched shunts can be installed additional to balance unnecessary lagging reactive power, if land wind energy turbine set is overall in capacitive, can install additional can switching Reactor banks to balance unnecessary capacitive reactive power.

The reactive power of wind energy turbine set can be divided into two class sources: a class is square proportional reactive power source or the load with grid-connected voltage, distribution capacity such as cable, the excitation reactance of transformer, and the switched capacitors of parallel connection and reactor, become 1 class load or burden without work by this type load.One class is square reactive power source being directly proportional or the load to electric current, such as the reactance of cable, the leakage reactance of transformer, this type load becomes 2 class load or burden without work.

The lagging reactive power making 1 class load or burden without work send is Q_C(U), there is following computing formula:

Q_C(U)=Q_CC-Q_MCR-Q_TRB=wCU²-U²/wL_MCR-B_TU²=(wC-B_T-1/wL_MCR)·U²；

Wherein, Q_C(U) for the lagging reactive power sent with square proportional reactive power source or the load of grid-connected voltage, w is angular frequency, and C is the capacity of wind energy turbine set, and U is grid-connected voltage, L_MCRFor the reactive compensation capacity of shunt reactor, B_TFor susceptance, L_CFor cable reactance value, L_TRFor transformer reactance value, P_WFThe active power sent for wind energy turbine set, Q_WFThe reactive power sent for wind energy turbine set；

As a example by marine wind electric field, owing to marine wind electric field submarine cable is more, marine wind electric field is overall in capacitive load, has wC ＞ B_T+1/wL_MCR, it is possible to know the capacitive reactive power Q that such load or burden without work sends_C(U) it is increasing function at U ∈ (0 ,+∞), i.e. works as U=U_maxTime 1 class load or burden without work to send capacitive reactive power maximum, work as U=U_minTime 1 class reactive power load to send capacitive reactive power minimum.

The lagging reactive power making 2 class load or burden without work send is Q_L(I), there is expression formula:

Q_L(I)=(wL_C+wL_TR)·I²=(wL_C+wL_TR)·(P_WF ²+Q_WF ²)/U²；

Can be known by above-mentioned formula, 2 class load or burden without work are completely sent out in wind energy turbine set, (P=P when grid-connected voltage is minimum_max, U=U_min) lagging reactive power that sends is maximum, unloaded at wind field, grid-connected voltage is up to P_WT=0, Q_WT=0, U=U_max, the lagging reactive power sent is minimum.

Summary is described, and the capacitive reactive power that whole marine wind electric field sends has Q_WF=Q_C(U)-Q_L(I), by above-mentioned analysis it is recognised that when wind energy turbine set zero load, blower fan does not send power, during grid-connected voltage maximum, i.e. P_WT=0, Q_WT=0, U=U_max, it is maximum that wind energy turbine set 1 class load or burden without work sends capacitive reactive power, and it is minimum that 2 class load or burden without work send lagging reactive power, so the capacitive reactive power that now wind energy turbine set sends is maximum, is designated as Q_Cmax.In like manner understand, when wind energy turbine set is fully loaded with, when grid-connected voltage is minimum, i.e. P=P_max, U=U_min, it is maximum that wind energy turbine set sends lagging reactive power, is designated as Q_Lmax.More than analyze, equally applicable for land wind energy turbine set.

Thus, it can be known that work as P_WT=0, Q_WT=0, U=U_maxTime, the maximum capacitive reactive power of available wind energy turbine set；Work as P_WT=P_N, U=U_minTime, the maximum inductive reactive power of available wind energy turbine set.

In a preferred embodiment, described computing module 23 can be additionally used in: when blower fan does not possess reactive power regulating power,

If Q_Cmax＞ Q_Lmax, according to reactive compensation capacity and the reactive compensation capacity of SVG device of the following formula described shunt reactor of calculating:

If Q_Cmax=Q_Lmax, the reactive compensation capacity of SVG device: C is calculated according to following formula_SVG=Q_Cmax；

If Q_Cmax＜ Q_Lmax, according to reactive compensation capacity and the reactive compensation capacity of SVG device of following formula calculating Shunt Capacitor Unit:

Wherein, L_MCRFor the reactive compensation capacity of shunt reactor, w is angular frequency, Q_CmaxFor described maximum capacitive reactive power, Q_LmaxFor described maximum inductive reactive power, C_SVGFor the reactive compensation capacity of SVG device, C_MSCReactive compensation capacity for Shunt Capacitor Unit.

When blower fan possesses reactive power regulating power, according to the reactive compensation capacity of following formula calculating reactive power compensator:

Wherein, L_MCRFor the reactive compensation capacity of shunt reactor, C_SVGReactive compensation capacity for SVG device.

In the present embodiment, when obtaining the maximum capacitive reactive power of wind energy turbine set and maximum inductive reactive power, it may be determined that reactive power compensator type, calculate the reactive compensation capacity of reactive power compensator, be divided into the following two kinds situation:

When not considering the reactive power regulating power of blower fan, as a example by marine wind electric field, the reactive power regulation of wind field only regulates by MCR and SVG, and the most only SVG has corresponding Reactive-power control ability.The filled SVG of wind field should be able to should be able to be fully compensated wind energy turbine set and reactive power that outlet line is sent when wind energy turbine set sends maximum capacitive or lagging reactive power, i.e. Q=0,Then have:

Above formula is solved, obtains the capacity C of SVG_SVGCapacity L with shunt reactor_MCR:

As seen from the above, the effect of reactor is that wind energy turbine set load character is adjusted equilibrium, if the equilibrium of wind field load character, has Q_Cmax-Q_Lmax=0, then parallel reactance L_MCR=∞ now C_SVG=Q_Cmax=Q_Lmax, i.e. need not to install switching reactor in parallel, the SVG capacity of installation is the capacitive that sends of wind energy turbine set and perception peak power.In like manner, if for land wind energy turbine set, if there being Q_Cmax＜ Q_Lmax, then opening-closing capacitor bank in parallel should be installed, have:

Above formula is solved, obtains the capacity C of SVG_SVGCapacity C with Shunt Capacitor Unit_MSC:

No matter install parallel reactance or shunt capacitance additional, be provided to Equilibrium Wind load, reduce the capacity of SVG；In two kinds of compensation ways, the capacity expression of SVG is just as.

In order to ensure meeting the grid-connected requirement of wind field, can leave allowance to reactive-load compensation configuration, reactance value capacity can be configured by calculated value, 110% the 120% of the desirable calculated value of capacity of SVG.

When considering the Reactive-power control ability of blower fan, according to GBT19963-2011 " wind energy turbine set accesses power system technology regulation ", specify grid-connected wind field blower fan should possess power factor dynamic adjustable ability, i.e.-0.312P in the range of advanced 0.95～delayed 0.95_WT≤Q_WT≤+0.312P_WT。

Because blower fan possesses the ability dynamically regulating reactive power, perception or capacitive reactive power can be sent according to controlling requirement, be equivalent to the function of SVG.When, after the Reactive-power control ability considering blower fan, increasing the regulating power of the reactive power of wind energy turbine set, simultaneously in terms of reactive-load compensation configuration, the biggest cost can be saved according to calculating the installed capacity suitably reducing SVG.But the reactive power regulating power of blower fan only could be considered when blower fan is incorporated into the power networks, randomness due to wind-resources, wind energy turbine set there may be some Fans at run duration and can not generate electricity by way of merging two or more grid systems for some reason operation, and now the reactive power regulating power of wind energy turbine set is also restricted.

Owing to grid-connected blower fan has possessed the idle dynamic regulating power of SVG, so the capacity of SVG can according to circumstances be reduced, from the angle of economy, use the scheme that cost is minimum to use reactor as the capital equipment compensated as far as possible, i.e. use jumbo reactor arrangement.

When considering wind field zero load, blower fan off-grid, take P_WT=0, Q_WT=0, U=U_max, the capacitive reactive power Q that wind field maximum sends can be obtained_Cmax.Now consider to use shunt reactor to compensate whole capacitive reactive power Q_Cmax。

Then have:

Can be by I_C=(wC_C-B_T)U_maxSubstitute into, then have:

Therefore, the capacity of the electrical equipment in parallel obtaining installation is:

L_MCR=1/w (wC_C-B_T)·(wC_C-B_T-wL_TR-wL_C)。

When blower fan is incorporated into the power networks, can inject to grid power and electric current, add the output of wind field lagging reactive power, but being incorporated to due to blower fan, also make wind field add corresponding blower fan Reactive-power control ability, the increase of some or all of lagging reactive power can be offset.Need to blower fan grid-connected after, the change of wind field reactive power calculates.

By fan operation rated power calculate, increase a Fans grid-connected after, wind energy turbine set increase capacitive reactive power deposit have:

Wherein, U is grid-connected voltage, and according to power supply quality requirement, typically i.e. can not have more than 10% for the voltage drop of transmission line in wind field:

Therefore capacitive reactive power deposit is:

So after in wind field, increase by one Fans is incorporated into the power networks, it practice, what the deposit of the capacitive reactive power of wind field was to increase.Mean when the grid-connected number of units of the blower fan in wind field gradually increases, the increase of the lagging reactive power that the electric current of wind energy turbine set output increases and causes, but the increments of lagging reactive power can be dissolved by the reactive power regulating power of blower fan, and grid-connected blower fan number of units is the most, the capacitive reactive power deposit of whole wind field will be the biggest.

Owing to the capacity of shunt reactor is L_MCR=1/w (wC_C-B_T)·(wC_C-B_T-wL_TR-wL_C), how the most grid-connected voltage changes, and the lagging reactive power that shunt reactor is issued can compensate reactive power that the distribution capacity of power down cable brings (including the consumption of the lagging reactive power that cable charge power and charge power brought).

So the most grid-connected voltage is how many, after the reactor installing respective volume additional, the Reactive-power control ability of blower fan can regulate the reactive power of whole wind field, makes the reactive power sent of whole wind field meet grid-connected requirement.Therefore consider power of fan factor in the range of advanced 0.95～delayed 0.95 dynamically can timing, only need to install shunt reactor additional and just can meet wind farm grid-connected regulation requirement, it is not necessary to install extra SVG device additional.In the case of Gai, obtain the capacity C of SVG_SVGCapacity L with shunt reactor_MCRHave

Actually the regulating power of blower fan tend not to meet grid-connected require regulation under any operating mode, power factor is the most adjustable in the range of advanced 0.95～delayed 0.95, so the capacity of SVG can the most suitably be increased, such as the capacity of SVG is set to 10% (or reactance value takes the 90% of calculated value, the 20% of the anti-calculated value of SVG capacity power taking) of reactor.

The collocation method of Reactive Compensation in Wind Farm of the present invention and system, by maximum capacitive reactive power and the maximum inductive reactive power of detection wind energy turbine set, reactive power regulating power further according to electric data, maximum capacitive reactive power, maximum inductive reactive power and blower fan, calculating the reactive compensation capacity of reactive power compensator, the calculating process of reactive compensation capacity is the quickest；Using shunt reactor, shnt capacitor or SVG device as reactive power compensator, on the premise of meeting wind farm grid-connected condition, use the most jumbo reactor, space the most more saved by reactor so that the control program of reactive-load compensation is more economically.

Embodiment described above only have expressed the several embodiments of the present invention, and it describes more concrete and detailed, but therefore can not be interpreted as the restriction to the scope of the claims of the present invention.It should be pointed out that, for the person of ordinary skill of the art, without departing from the inventive concept of the premise, it is also possible to make some deformation and improvement, these broadly fall into protection scope of the present invention.Therefore, the protection domain of patent of the present invention should be as the criterion with claims.

Claims (4)

1. the collocation method of a Reactive Compensation in Wind Farm, it is characterised in that comprise the steps:

Gather the electric data of wind energy turbine set；

According to described electric data and default wind energy turbine set electrical simulation model, measure the maximum capacitive of wind energy turbine set Reactive power and maximum inductive reactive power；

According to described electric data, maximum capacitive reactive power, maximum inductive reactive power and the nothing of blower fan Merit power adjusting ability, determines the type of reactive power compensator and calculates the reactive-load compensation of reactive power compensator Capacity；Wherein, described reactive power compensator is shunt reactor and SVG device or is shnt capacitor and SVG Device；

The reactive power compensator being configured with described reactive compensation capacity is installed in the also site of described wind energy turbine set；

Wherein, described according to described electric data and preset wind energy turbine set electrical simulation model, measure wind energy turbine set Maximum capacitive reactive power and the step of maximum inductive reactive power include:

According to described wind energy turbine set electrical simulation model, make P_WT=0, Q_WT=0, U=U_max, it is thus achieved that described Big capacitive reactive power；Wherein, P_WTThe active power sent for blower fan, Q_WTThe idle merit sent for blower fan Rate, U is grid-connected voltage, U_maxThe grid-connected voltage of maximum for default wind energy turbine set；

According to described wind energy turbine set electrical simulation model, make P_WT=P_N, U=U_min, it is thus achieved that described maximum inductive without Merit power；Wherein, P_NFor the specified active power of blower fan, U_minThe grid-connected voltage of minimum for default wind energy turbine set； When blower fan does not possess reactive power regulating power,

If Q_Cmax＞ Q_Lmax, reactive compensation capacity and the SVG device of described shunt reactor is calculated according to following formula Reactive compensation capacity:

$\left\{\begin{array}{c}{L}_{MCR}=({U_{max}}^2+{U_{\min }}^2)/w(Q_{Cmax}-Q_{Lmax})\\ C_{SVG}\≥({U_{\max }}^2{Q}_{L\max }+{U_{\min }}^2{Q}_{Cmax})/({U_{\max }}^2+{U_{\min }}^2)\end{array}\right.;$

If Q_Cmax=Q_Lmax, the reactive compensation capacity of SVG device: C is calculated according to following formula_SVG=Q_Cmax；

If Q_Cmax＜ Q_Lmax, reactive compensation capacity and the nothing of SVG device of shnt capacitor is calculated according to following formula Merit compensation capacity:

$\left\{\begin{array}{c}{C}_{MSC}=(Q_{Lmax}-Q_{Cmax})/w({U_{max}}^2+{U_{\min }}^2)\\ C_{SVG}\≥({U_{max}}^2{Q}_{Lmax}+{U_{\min }}^2{Q}_{Cmax})/({U_{\max }}^2+{U_{\min }}^2)\end{array}\right.;$

Wherein, Q_CmaxFor described maximum capacitive reactive power, Q_LmaxFor described maximum inductive reactive power, L_MCR For the reactive compensation capacity of shunt reactor, w is angular frequency, C_SVGFor the reactive compensation capacity of SVG device, C_MSCReactive compensation capacity for shnt capacitor.

The collocation method of Reactive Compensation in Wind Farm the most according to claim 1, it is characterised in that work as wind When facility are for reactive power regulating power, according to the reactive compensation capacity of following formula calculating reactive power compensator:

$\left\{\begin{array}{c}{L}_{MCR}=1/w\·(w{C}_C-B_T)\·(w{C}_C-B_T-w{L}_{TR}-w{L}_C)\\ C_{SVG}=0\end{array}\right.$

Wherein, w is angular frequency, C_CFor cable capacitance value, B_TFor transformer susceptance value, L_CFor cable reactance Value, L_TRFor transformer reactance value, L_MCRFor the reactive compensation capacity of shunt reactor, C_SVGFor SVG device Reactive compensation capacity.

3. the reactive-load compensation configuration system of a wind energy turbine set, it is characterised in that include reactive power compensator, institute State reactive power compensator to be shunt reactor and SVG device or be shnt capacitor and SVG device, also wrap Include:

Acquisition module, for gathering the electric data of wind energy turbine set；

Measurement module, for according to described electric data and default wind energy turbine set electrical simulation model, measuring wind The maximum capacitive reactive power of electric field and maximum inductive reactive power；

Computing module, for according to described electric data, maximum capacitive reactive power, maximum inductive is idle merit The reactive power regulating power of rate and blower fan, determines the type of reactive power compensator and calculates reactive-load compensation The reactive compensation capacity of device；

Described reactive power compensator is configured with described reactive compensation capacity, and is arranged on the grid-connected of described wind energy turbine set Point；

Wherein, described measurement module is additionally operable to:

According to described wind energy turbine set electrical simulation model, make P_WT=0, Q_WT=0, U=U_max, it is thus achieved that described Big capacitive reactive power；Wherein, P_WTThe active power sent for blower fan, Q_WTThe idle merit sent for blower fan Rate, U is grid-connected voltage, U_maxThe grid-connected voltage of maximum for default wind energy turbine set；

According to described wind energy turbine set electrical simulation model, make P_WT=P_N, U=U_min, it is thus achieved that described maximum inductive without Merit power；Wherein, P_NFor the specified active power of blower fan, U_minThe grid-connected voltage of minimum for default wind energy turbine set；

Described computing module is additionally operable to: when blower fan does not possess reactive power regulating power,

If Q_Cmax＞ Q_Lmax, reactive compensation capacity and the SVG device of described shunt reactor is calculated according to following formula Reactive compensation capacity:

$\left\{\begin{array}{c}{L}_{MCR}=({U_{max}}^2+{U_{\min }}^2)/w(Q_{Cmax}-Q_{Lmax})\\ C_{SVG}\≥({U_{\max }}^2{Q}_{L\max }+{U_{\min }}^2{Q}_{Cmax})/({U_{\max }}^2+{U_{\min }}^2)\end{array}\right.;$

If Q_Cmax=Q_Lmax, the reactive compensation capacity of SVG device: C is calculated according to following formula_SVG=Q_Cmax；

If Q_Cmax＜ Q_Lmax, reactive compensation capacity and the nothing of SVG device of shnt capacitor is calculated according to following formula Merit compensation capacity:

$\left\{\begin{array}{c}{C}_{MSC}=(Q_{Lmax}-Q_{Cmax})/w({U_{max}}^2+{U_{\min }}^2)\\ C_{SVG}\≥({U_{max}}^2{Q}_{Lmax}+{U_{\min }}^2{Q}_{Cmax})/({U_{\max }}^2+{U_{\min }}^2)\end{array}\right.;$

Wherein, L_MCRFor the reactive compensation capacity of shunt reactor, w is angular frequency, Q_CmaxFor described maximum appearance Property reactive power, Q_LmaxFor described maximum inductive reactive power, C_SVGFor the reactive compensation capacity of SVG device, C_MSCReactive compensation capacity for shnt capacitor.

The reactive-load compensation configuration system of wind energy turbine set the most according to claim 3, it is characterised in that described Computing module is additionally operable to: when blower fan possesses reactive power regulating power, calculates reactive-load compensation dress according to following formula The reactive compensation capacity put:

$\left\{\begin{array}{c}{L}_{MCR}=1/w\·(w{C}_C-B_T)\·(w{C}_C-B_T-w{L}_{TR}-w{L}_C)\\ C_{SVG}=0\end{array}\right.$

Wherein, w is angular frequency, C_CFor cable capacitance value, B_TFor transformer susceptance value, L_CFor cable reactance Value, L_TRFor transformer reactance value, L_MCRFor the reactive compensation capacity of shunt reactor, C_SVGFor SVG device Reactive compensation capacity.