CN102570483B - Reactive voltage regulation de-mismatching method of 220kV power transformer substation - Google Patents

Abstract

The invention discloses a reactive voltage regulation de-mismatching method of a 220kV power transformer substation, which carries out quantitative evaluation to the regulation mismatch risk of the reactive voltage of the electric grid at the provincial and prefectural levels caused in the operation management. When the risk exceeds a threshold, the de-mismatching strategy is started, so that the problems of the operation security and the economy of the big electric grid caused by the regulation mismatching of the reactive voltage due to the improper match of the electric grid control strategies at the provincial and prefectural levels are solved so as to make up for the blank of the engineering field. The method concretely comprises the following steps: firstly, monitoring state variable of the 220kV power transformer substation; then, respectively calculating corresponding mismatch indexes and operation mismatching indexes delta epsilon; and finally, starting the de-mismatching strategy when the risk exceeds the threshold. Therefore, the full-grid reactive power trend is optimized, and various voltage levels of the system are improved.

Description

Mismatch method is gone in the reactive voltage regulation and control of 220kV transformer station

Technical field

The present invention relates to large electrical network and economize the operational management skill that ground reactive voltage regulation and control coordinate, be specifically related to the reactive voltage regulation and control of 220kV transformer station and go mismatch method.

Background technology

Automatism voltage control (Automatic Voltage Control is called for short AVC) becomes the Main Means of reactive voltage regulation and control gradually.Under conventional operation mode, economize to adjust and can utilize AVC, by existing AVC strategy, under less reactive voltage Readjusting cost, realize the regional control of electric network reactive-load voltage and proofread and correct on the spot.But find in practice, under extreme operational mode, there is limitation in existing AVC strategy, is often difficult to guarantee to make full use of 220kV transformer station reactive power/voltage control equipment and takes into account the demand of province's ground two-stage electric network reactive-load regulating and controlling voltage, the overall situation that is difficult to the to realize electric network reactive-load voltage excellent control that becomes.Although now step down side voltage V _lwith the idle Q in critical point _hbe in the interval of acceptance of control strategy, transformer station there is available idle resource but reactive voltage control system without conduct, cause high voltage side of transformer voltage V _hstill there is regulation and control mismatch phenomenon higher or on the low side.

For lower floor's electrical network, regulate 220kV main transformer of transformer substation tap to carry out the optimal selection that region regulating and controlling voltage is its coordination control strategy, can entirety improve lower floor's grid voltage quality and minimal manipulation, even if still have can the idle resource of switching for this lower floor's electrical network, also can maintain motionless.Meanwhile, due to capacitor, reactor, the first-class discrete adjustment equipment that belongs to limited number of times of main transformer tap, need to consider Readjusting cost, too frequent switching.Under conventional operation mode, the many Primary regulations of certain transformer station or few Primary regulation are little for the energy-saving and cost-reducing impact of electrical network entirety, so that the idle definite value interval of acceptance of AVC arranges wider conventionally, so that lower floor's reactive voltage reduces the operation of adjusting device compared with easily reaching eligible state.Therefore, if critical point voltage is high, mesolow side voltage is not out-of-limit, as long as critical point, high-pressure side is idle not out-of-limit, the reactive power compensation of lower floor's electrical network can not made regulation and control equally.But this has just destroyed the optimization situation of idle in-situ balancing, in Practical Project, often show as lower floor's grid equipment regulation and control number of times few, and brought larger difficulty to upper strata electrical network regulation and control.

For upper strata electrical network, 220kV main transformer of transformer substation high side voltage V _hhigher (or on the low side) means this region idle more than needed (or in short supply), if absorb (or under send) by upper strata electrical network, difficulty will lighten along with system loading level (or becoming heavy) and increase.And from the angle of the whole network idle work optimization, by power plant, a distant place or 500kV transformer station, carry out idle control and be unfavorable for saving energy and reduce the cost compared with the idle in-situ balancing of each 220kV transformer station.Therefore, in fact upper strata electrical network is to wish first to set about the idle regulation and control in region to make every effort to idle in-situ balancing, finally carries out region regulating and controlling voltage.Still more, the result of 220kV main transformer pressure regulation can cause the reactive power flow of levels further to worsen.Especially under extreme operational mode, along with lower floor's electrical network send (or consumption) idle increasing, lower floor's electrical network too relies on the regulation and control of upper strata electrical network, and grid loss increases, and when serious, the voltage security that affects electrical network is stablized.Now need lower floor's electrical network suitably to absorb (sending) reactive power to support upper strata electrical network regulation and control.

Therefore, in the urgent need to the province's ground two-stage electric network reactive-load regulating and controlling voltage mismatch risk to causing in operational management, carry out qualitative assessment.When risk does not exceed threshold value, maintain existing AVC strategy, when risk exceedes threshold value, start and remove mismatch strategy, to solve owing to economizing the problem of adjusting two-stage power grid control strategy mismate that reactive voltage regulation and control mismatch occurs with ground and then affecting large safe operation of electric network and economy of adjusting.To optimize the whole network reactive power flow, improvement system voltage levvls at different levels.

Summary of the invention

The object of the present invention is to provide the reactive voltage regulation and control of a kind of 220kV transformer station to go mismatch method, the province's ground two-stage electric network reactive-load regulating and controlling voltage mismatch risk causing in operational management is carried out to qualitative assessment, when risk exceedes threshold value, start and remove mismatch strategy, for solving owing to economizing the problem of adjusting two-stage power grid control strategy mismate that reactive voltage regulation and control mismatch occurs with ground and then affecting large safe operation of electric network and economy of adjusting.

Mismatch method is gone in the reactive voltage regulation and control of 220kV of the present invention transformer station, comprises step:

(1) state variable in monitoring each moment of 220kV transformer station, i.e. main transformer high side voltage V _h, main transformer low-pressure side voltage V _l, critical point is idle Q _hwith available reactive compensation capacity Q in station _c;

(2) calculate the mismatch index of above-mentioned variable, comprise main transformer high side voltage mismatch λ _vH, main transformer low-pressure side voltage mismatch λ _vL, critical point is idle mismatch λ _qH, stand in available idle resource mismatch degree λ _qC;

(3) by fuzzy operator, realize the integration of These parameters, obtain the regulating and controlling voltage mismatch risk of this transformer station, move mismatch δ _∑;

(4) when operation mismatch exceedes threshold value δ ₀time, if main transformer high side voltage V _hhigher, higher than soft-constraint upper limit V _hmax, exit capacitor to be cut, or drop into reactor to be thrown; If main transformer high side voltage V _hon the low side, lower than soft-constraint lower limit V _hmin, exit reactor to be cut, or drop into capacitor to be thrown.

In said method, the reactive voltage that 220kV substation presents regulates and controls mismatch and refers to, under more extreme operational mode, i.e. and heavy duty or underloading, main transformer low-pressure side voltage V _lwith the idle Q in critical point _hbe in the interval of acceptance of control strategy, transformer station there is available idle resource but reactive voltage control system without conduct, cause main transformer high side voltage V _hstill there is regulation and control mismatch phenomenon higher or on the low side.

Wherein, the correlated variables of transformer station, i.e. main transformer high side voltage V _h, main transformer low-pressure side voltage V _l, critical point is idle Q _hwith available reactive compensation capacity Q in station _c, reflected that the reactive voltage of formation transformer station regulates and controls each factor of mismatch phenomenon.Can use the mismatch risk that mathematical tool causes each factor to quantize, obtain corresponding substation operation mismatch index.

In the present invention, the mismatch index of the relevant operation of transformer station variable, comprises main transformer high side voltage mismatch λ _vH, main transformer low-pressure side voltage mismatch λ _vL, critical point is idle mismatch λ _qHavailable idle resource mismatch degree λ in standing _qC

(1) main transformer high side voltage mismatch λ _vHcalculating:

By main transformer high side voltage V _hsubstitution formula (1), calculates and obtains main transformer high side voltage mismatch λ _vH,

${\mathrm{\λ}}_{\mathrm{VH}}=\left\{\begin{array}{cc}1& V_H\∈\left(\mathrm{0.900,0.987}\right)\\ e^{-{\left(\frac{V_H-0.9870}{0.0215}\right)}^2}& V_H\∈\left[\mathrm{0.987,1.050}\right]\\ e^{-{\left(\frac{V_H-1.0700}{0.0072}\right)}^2}& V_H\∈\left[\mathrm{1.050,1.070}\right]\\ 1& V_H\∈\left(\mathrm{1.070,1.100}\right)\end{array}\right.---\left(1\right)$

Main transformer high side voltage V in formula _hsoft-constraint bound V _hmaxand V _hminperunit value be respectively 1.064,1.005, the perunit value of hard constraint bound is respectively 1.070,0.970, described soft-constraint is transforming plant voltage reactive Comprehensive Control (Voltage Quality Control, be called for short VQC) or automatism voltage control (Automatic Voltage Control, be called for short AVC) the upper lower limit value of voltage interval of acceptance, described hard constraint is the upper lower limit value of main transformer high side voltage examination interval of acceptance in the reactive voltage regulation and control of 220kV transformer station;

The selection of formula (1) relevant parameter is to consider, main transformer high side voltage V in engineering _hwhen interval in [1.020,1.060], grid net loss is less, and performance driving economy is better, if this interval bound of voltage deviation is more, moves mismatch risk higher, considers main transformer high side voltage V _hmore between deviation area, the upper limit is larger on the impact of substation equipment, makes to quantize main transformer high side voltage V _hmain transformer high side voltage mismatch λ in [1.050,1.070] interval in the mismatch risk function curve of gained _vHincrease progressively the interval slope absolute value that successively decreases of slope relative [0.987,1.050] larger;

Therefore, under large mode, main transformer high side voltage V _hon the low side, main transformer high side voltage mismatch λ _vHwith main transformer high side voltage V _hsuccessively decrease and monotonic increase.As main transformer high side voltage V _hexceed under soft-constraint and prescribe a time limit, main transformer high side voltage mismatch λ _vHrapidly close to 1, main transformer high side voltage V _hperunit value is 1.005 o'clock, main transformer high side voltage mismatch λ _vHbe 0.5.Under little mode, main transformer high side voltage V _hhigher, main transformer high side voltage mismatch λ _vHwith main transformer high side voltage V _hincrease progressively and monotonic increase.As main transformer high side voltage V _happroach in soft-constraint and prescribe a time limit, 1.070 o'clock, main transformer high side voltage mismatch λ _vHrapidly close to 1, main transformer high side voltage V _hperunit value is 1.064 o'clock, main transformer high side voltage mismatch λ _vHbe 0.5.As main transformer high side voltage V _hwhen interval in [1.020,1.060], reactive voltage regulating effect is comparatively desirable, now main transformer high side voltage mismatch λ _vHclose to 0.

(2) main transformer low-pressure side voltage mismatch λ _vLwith the idle mismatch λ in critical point _qHcalculating:

By main transformer low-pressure side voltage V _lsubstitution formula (2), calculates and obtains main transformer low-pressure side voltage mismatch λ _vL; By idle critical point Q _hsubstitution formula (3), calculates and obtains the idle mismatch λ in critical point _qH,

${\mathrm{\λ}}_{\mathrm{VL}}=\left\{\begin{array}{cc}1& V_L\∈[V_{\min },V_{\max }]\\ 0& V_L\∉[V_{\min },V_{\max }]\end{array}\right.---\left(2\right)$

${\mathrm{\λ}}_{\mathrm{QH}}=\left\{\begin{array}{cc}1& Q_H\∈[Q_{\min },Q_{\max }]\\ 0& Q_H\∉[Q_{\min },Q_{\max }]\end{array}\right.---\left(3\right)$

In formula, V _maxand V _minbe respectively the upper lower limit value of main transformer low-pressure side voltage soft-constraint, Q _maxand Q _minbe respectively the idle upper lower limit value in main transformer critical point;

The selection of formula (2) and formula (3) relevant parameter is to consider, when the out-of-limit phenomenon of the idle appearance of main transformer low-pressure side voltage or critical point, can proofread and correct on the spot by the VQC of transformer station or AVC system, the underproof main cause of appearance that main transformer of transformer substation low-pressure side voltage or critical point are idle is reactive voltage regulation and control inadequate resource in station, and this mismatch situation does not belong to the category that moves mismatch, make step down side voltage, critical point is idle interval of acceptance be operation mismatch necessary condition.

(3) stand in available idle resource mismatch degree λ _qCcalculating:

Under large mode, by the capacity Q of available idle resource in station _csubstitution formula (4), available idle resource mismatch degree λ in acquisition station _qC; Under little mode, by Q _csubstitution formula (5), available idle resource mismatch degree λ in acquisition station _qC,

${\mathrm{\&lambda;}}_{\mathrm{QC}}=\left\{\begin{array}{cc}1& Q_C\&GreaterEqual;{\mathrm{<figure-callout\; id="0"\; label="Q\; C"\; filenames="HDA0000135572580000021.png,HDA0000135572580000031.png"\; state="\{\{state\}\}">Q</figure-callout>}}_C\\ 0& Q_C=0\end{array}\right.---\left(4\right)$

${\mathrm{\&lambda;}}_{\mathrm{QC}}=\left\{\begin{array}{cc}1& Q_C\&le;-{\mathrm{<figure-callout\; id="0"\; label="Q\; C"\; filenames="HDA0000135572580000021.png,HDA0000135572580000031.png"\; state="\{\{state\}\}">Q</figure-callout>}}_C\\ 0& Q_C\&GreaterEqual;0\end{array}\right.---\left(5\right)$

Q in formula _c0for single group compensation capacity;

The selection of formula (4) and formula (5) relevant parameter is to consider, under automatic voltage control system control, in standing, whether idle resource can be by the mismatch degree that has reflected transformer station, under large mode, and main transformer high side voltage V _hon the low side, main transformer high side voltage mismatch λ _vHbe greater than at 0.5 o'clock, in standing, existence can be thrown capacitor but not throw, or has and can cut reactor but not cut, and is the necessary condition of reactive voltage regulation and control operation mismatch phenomenon, otherwise does not belong to operation mismatch category; Under little mode, main transformer high side voltage V _hhigher, main transformer high side voltage mismatch λ _vHbe greater than at 0.5 o'clock, in standing, existence can be thrown reactor but not throw, and maybe can cut capacitor but not cut, it is the necessary condition of reactive voltage regulation and control operation mismatch phenomenon, otherwise do not belong to operation mismatch category, can throw capacitor and be equivalent to and can cut reactor, can cut capacitor and be equivalent to and can throw reactor.

The present invention integrates corresponding mismatch index by fuzzy operator, obtains operation mismatch index δ _∑, can be used to show the mismatch risk of whole transformer station:

δ _∑＝(λ _QH∧λ _VL)g(λ _QC∧λ _VH)(6)

In formula (6), ∧ and be fuzzy operator, ∧ gets the minimum value in each index, represents common real multiplications; Only has λ _qHand λ _vLbe all 1, low-pressure side voltage and critical point idle all qualified be operation mismatch necessary condition; (λ _qC∧ λ _vH) main transformer high side voltage mismatch λ has been described under automatic voltage control system control in station when existence can switching reactive power compensation _vHit is the key influence factor of transformer station's mismatch degree.

The 0.5th, the present invention carries the threshold value δ of operation mismatch ₀, as the operation mismatch δ of assessment gained _∑be greater than at 0.5 o'clock, illustrate that regulation and control mismatch phenomenon appears in this transformer station, and along with the increase of mismatch risk, mismatch degree is increasing; And calculate the δ of gained when transformer station _∑being less than at 0.5 o'clock, there is not regulating and controlling mismatch in this transformer station, but along with the increase of mismatch risk, more approaches 0.5, and the risk that regulation and control mismatch occurs is larger.

Compared with prior art, the present invention has filled up the blank of engineering circles, has the following advantages:

(1) the present invention has realized the qualitative assessment of economizing ground two-stage electric network reactive-load regulating and controlling voltage mismatch risk;

(2) the present invention emphasizes only when mismatch risk exceedes threshold value, just start and remove mismatch strategy, make 220kV transformer station preferentially assist upper strata electrical network to carry out the idle regulation and control in region, mismatch risk hour, 220kV transformer station serves lower floor's line voltage regulation and control needs, rather than whenever all serve the idle regulation and control demand in upper strata, avoid the frequent movement of adjusting device;

(3) the present invention realizes coordination and the optimization of province's ground levels electric network reactive-load regulating and controlling voltage.To optimize the whole network reactive power flow, improvement system voltage levvls at different levels.

Accompanying drawing explanation

Fig. 1 is that the flow chart of mismatch method is removed in the reactive voltage regulation and control of 220kV of the present invention transformer station.

Fig. 2 is the idle curve in critical point, practical operation situation main transformer high-pressure side.

Fig. 3 is practical operation situation main transformer high and low pressure side voltage and operation mismatch curve.

Fig. 4 is that the present invention applies rear main transformer high and low pressure side voltage and operation mismatch curve.

Embodiment

Below Guangdong Power Grid 220kV Dong Tang transformer station is carried out to instance analysis.This transformer station's power supply area contains some small power stations, has again mining industry and Metallurgy Industry, and load fluctuation is larger.

In conjunction with Fig. 1 estimation flow, the reactive voltage regulation and control of 220kV transformer station go mismatch method to comprise the following steps:

(1) state variable in monitoring each moment of Dong Tang transformer station, i.e. main transformer high side voltage V _h, main transformer low-pressure side voltage V _l, critical point is idle Q _hwith available reactive compensation capacity Q in station _c;

(2) calculate the mismatch index of above-mentioned variable, comprise main transformer high side voltage mismatch λ _vH, main transformer low-pressure side voltage mismatch λ _vL, critical point is idle mismatch λ _qH, stand in available idle resource mismatch degree λ _qC;

(3) by fuzzy operator, realize the integration of These parameters, obtain the regulating and controlling voltage mismatch risk of this transformer station, move mismatch δ _∑;

(4) when operation mismatch exceedes 0.5, if main transformer high side voltage V _hhigher, higher than soft-constraint upper limit V _hmax, exit capacitor to be cut, or drop into reactor to be thrown; If main transformer high side voltage V _hon the low side, lower than soft-constraint lower limit V _hmin, exit reactor to be cut, or drop into capacitor to be thrown.

This station #1 main transformer of providing take grid company under little mode 2011 96 operating points of whole day on January 15, (section) are example, this main transformer disposes the reactor that capacitor that 2 pool-sizes are 7.8Mvar and 2 pool-sizes are 8Mvar, Fig. 2 shows the idle curve in each operating point main transformer critical point, and Fig. 3 shows each operating point main transformer high and low pressure side voltage and operation mismatch curve.Reactive voltage regulating effect (Fig. 4) after practical operation situation (Fig. 2 and Fig. 3) under existing AVC strategy and employing the present invention is contrasted, and in the subscript of each variable, 0 represents actual motion state, and 1 represents to go mismatch Conditions.The threshold value of AVC strategy is as shown in table 1.

The tactful definite value of table 1

One group, the former input capacitor of #1 main transformer.Under existing AVC policy control, although one day 96 interior step down side voltage V _lwith the idle Q on high-tension side critical point _hin interval of acceptance, but since 19, critical point is idle Q _hfor negative, power factor approaches 1.0, and main transformer high side voltage V _hhigher, higher than 234.0kV, even repeatedly higher than permissible value 235.4kV, be the 1.07p.u. in Fig. 3, illustrate that now upper strata electrical network is strong to the demand of lower floor's electric network reactive-load regulating and controlling voltage assistance, and this main transformer maintained the input state of a group capacitor same day always, can not utilize in station can with idle adjusting device support upper strata electrical network, there is reactive voltage of the present invention regulation and control mismatch phenomenon.

If now capacitor is exited, will be favourable to total system: both guaranteed the situation of the idle in-situ balancing of upper strata electrical network, and reduced again station equipment and operation of power networks risk that overvoltage is brought.This has just shown that existing regional AVC strategy lacks under little mode and has regulated and controled responsible power for upper strata electrical network.Now move mismatch δ _∑higher, repeatedly reach 1.0.

And after employing the present invention, can exit in the 19th group capacitor of naming a person for a particular job.After exiting, main transformer high side voltage V _hstill higher, but operation mismatch δ _∑obviously reduce, lower than 0.5.Subsequently according to strategy will the 49th and 54 in succession drop into two groups of reactors, under critical point, send idle increasing, effectively supported upper strata electric network reactive-load regulating and controlling voltage, operation mismatch δ _∑although higher than 0.5, lower than Fig. 3.The 54th to 73 owing to can throwing without reactor, even if main transformer high side voltage exceedes 234kV, now reactive voltage regulation and control inadequate resource in station, does not belong to problem solved by the invention, and interior available idle resource mismatch degree λ stands _qCbe zero, therefore moving mismatch is zero.Until in the time of the 74th, along with exiting of one group of reactor, available idle resource mismatch degree λ in standing _qCrevert to 1.0, main transformer high side voltage V _hgot back to above the average, but main transformer low-pressure side voltage V now _lmore lower limit, will exit one group of reactor according to strategy.In the time of the 90th, due to the idle Q in critical point _hmore the upper limit, will exit one group of reactor again.

As seen from Figure 4, the main transformer low-pressure side voltage V of whole day after employing the present invention _lwith the idle Q in critical point _hall meet original AVC criterion, and avoided main transformer high side voltage V _hhigher than permissible value 235.4kV, i.e. hard constraint, out-of-limit situation, system voltage quality and device security are improved, operation mismatch obviously reduce.Although the same day, the action frequency of idle conditioning equipment increased to some extent, every equipment is also just thrown and has been moved back respectively once at most, and Readjusting cost is little, allows completely.

Adopt after the present invention, the relative Fig. 3 of Fig. 4 moves mismatch δ _∑obviously reduce.But due to single station go mismatch regulation and control limited to the influence power of upper strata electric network reactive-load voltage levvl, cause at 49 to 74 points, when upper strata electric network reactive-load surplus voltage is higher, the mismatch regulation and control of going of our station could not avoid moving mismatch δ _∑higher than 0.5 operating point.Therefore, for improving upper strata electric network reactive-load voltage levvl, need to consider to adopt the present invention in the multiple transformer stations in region, could in region, realize effective support of lower floor's electrical network to upper strata electrical network, finally improve region reactive voltage level.

Visible, the present invention can carry out qualitative assessment to strategy shortcoming under any moment or the improper province's ground two-stage electric network reactive-load regulating and controlling voltage mismatch risk causing, make usual manner 220kV transformer station preferentially assist lower floor's electrical network to carry out region regulating and controlling voltage, when mismatch risk exceedes threshold value, 220kV transformer station preferentially assists upper strata electrical network to carry out the idle regulation and control in region, thus final coordination and the optimization that realizes province's ground levels electric network reactive-load regulating and controlling voltage.

Above-described embodiment is preferably execution mode of the present invention; but embodiments of the present invention are not restricted to the described embodiments; other are any does not deviate from modification, the modification done under Spirit Essence of the present invention and principle, substitute, combination, simplify; all should be equivalent substitute mode, within all protection scope of the present invention should being included in.

Claims (6)

1. Mismatch method is gone in the reactive voltage regulation and control of 1.220kV transformer station, it is characterized in that comprising the following steps:

   (1) state variable in monitoring each moment of 220kV transformer station, i.e. main transformer high side voltage V _h, main transformer low-pressure side voltage V _l, critical point is idle Q _hcapacity Q with available idle resource in station _c;

   (2) calculate the mismatch index of above-mentioned variable, comprise main transformer high side voltage mismatch λ _vH, main transformer low-pressure side voltage mismatch λ _vL, critical point is idle mismatch λ _qH, stand in available idle resource mismatch degree λ _qC; Described main transformer high side voltage mismatch λ _vHby obtaining below:

   By main transformer high side voltage V _hsubstitution formula (1), calculates and obtains main transformer high side voltage mismatch λ _vH,

   ${\mathrm{\&lambda;}}_{\mathrm{vh}}=\left\{\begin{array}{cc}1& V_H\&Element;\left(\mathrm{0.900,0.987}\right)\\ e^{{-\left(\frac{V_H-0.9870}{0.0245}\right)}^2}& V_H\&Element;\left[\mathrm{0.987,1.050}\right)\\ e^{-{\left(\frac{V_H-1.0700}{0.0072}\right)}^2}& V_H\&Element;\left[\mathrm{1.050,1.070}\right]\\ 1& V_H\&Element;\left(\mathrm{1.070,1.100}\right)\end{array}\right.---\left(1\right)$

   Main transformer high side voltage V in formula _hsoft-constraint bound V _hmaxand V _hminperunit value be respectively 1.064,1.005, the perunit value of hard constraint bound is respectively 1.070,0.970, described soft-constraint is the upper lower limit value of the voltage interval of acceptance of transforming plant voltage reactive Comprehensive Control or automatism voltage control, and described hard constraint is the upper lower limit value of main transformer high side voltage examination interval of acceptance during the reactive voltage of 220kV transformer station regulates and controls;

   (3) by fuzzy operator, realize the integration of These parameters, obtain the regulating and controlling voltage mismatch risk of this transformer station, move mismatch δ _∑;

   (4) when operation mismatch exceedes threshold value δ ₀time, if main transformer high side voltage V _hhigher, higher than soft-constraint upper limit V _hmax, exit capacitor to be cut, or drop into reactor to be thrown; If main transformer high side voltage V _hon the low side, lower than soft-constraint lower limit V _hmin, exit reactor to be cut, or drop into capacitor to be thrown.
2. 2. mismatch method is gone in the regulation and control of 220kV according to claim 1 transformer station reactive voltage, it is characterized in that described reactive voltage regulation and control mismatch is under heavy duty or light running mode, the mismatch phenomenon that 220kV transformer station reactive voltage regulates and controls to present, mismatch phenomenon is:

   Under heavy duty or light running mode, main transformer low-pressure side voltage V _lwith the idle Q in critical point _hbe in the interval of acceptance of control strategy, transformer station there is available idle resource but reactive voltage control system without conduct, cause main transformer high side voltage V _hstill there is regulation and control mismatch phenomenon higher or on the low side.
3. 3. mismatch method is gone in the regulation and control of 220kV according to claim 1 transformer station reactive voltage, it is characterized in that the main transformer low-pressure side voltage mismatch λ that step (2) is described _vLwith the idle mismatch λ in critical point _qHby following methods, obtained:

   By main transformer low-pressure side voltage V _lsubstitution formula (2), calculates and obtains main transformer low-pressure side voltage mismatch λ _vL; By idle critical point Q _hsubstitution formula (3), calculates and obtains the idle mismatch λ in critical point _qH,

   ${\mathrm{\&lambda;}}_{\mathrm{VL}}=\left\{\begin{array}{cc}1& V_L\&Element;[V_{\min },V_{\max }]\\ 0& V_L\&NotElement;[V_{\min },V_{\max }]\end{array}\right.---\left(2\right)$

   ${\mathrm{\&lambda;}}_{\mathrm{QH}}=\left\{\begin{array}{cc}1& Q_H\&Element;[Q_{\min },Q_{\max }]\\ 0& Q_H\&NotElement;[Q_{\min },Q_{\max }]\end{array}\right.---\left(3\right)$

   In formula, V _maxand V _minbe respectively the upper lower limit value of main transformer low-pressure side voltage soft-constraint, Q _maxand Q _minbe respectively the idle upper lower limit value in main transformer critical point.
4. 4. mismatch method is gone in the regulation and control of 220kV according to claim 1 transformer station reactive voltage, it is characterized in that available idle resource mismatch degree λ in the described station of step (2) _qCby following mode, obtained:

   Under large mode, by the capacity Q of available idle resource in station _csubstitution formula (4), available idle resource mismatch degree λ in acquisition station _qC; Under little mode, by Q _csubstitution formula (5), available idle resource mismatch degree λ in acquisition station _qC,

   ${\mathrm{\&lambda;}}_{\mathrm{QC}}=\left\{\begin{array}{cc}1& Q_C\&GreaterEqual;Q_{C0}\\ 0& Q_C=0\end{array}\right.---\left(4\right)$

   

   Q in formula _c0for single group compensation capacity.
5. 5. mismatch method is gone in the regulation and control of 220kV according to claim 1 transformer station reactive voltage, it is characterized in that the operation mismatch δ that step (3) is described _∑by following methods, obtained:

   The main transformer high side voltage mismatch λ of gained will be calculated _vH, main transformer low-pressure side voltage mismatch λ _vL, critical point is idle mismatch λ _qH, stand in available idle resource mismatch degree λ _qCsubstitution formula (6), calculates the mismatch risk that obtains this transformer station, moves mismatch δ _∑,

   δ _∑=(λ _QH∧λ _VL)·(λ _QC∧λ _VH) (6)

   In formula (6), ∧ and be fuzzy operator, ∧ gets the minimum value in each index, represents common real multiplications.
6. 6. mismatch method is gone in the regulation and control of 220kV according to claim 1 transformer station reactive voltage, it is characterized in that the threshold value δ of the described operation mismatch of step (4) ₀0.5.

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