CN103166226B - Network voltage reactive-power compound coordination control system and method for new energy power generation - Google Patents

Abstract

The invention belongs to the technical field of voltage and reactive power control for grid-connected operation of wind power, photovoltaic and other new energy power generation in electrical engineering, and particularly relates to a grid voltage and reactive power composite coordinated control system and method for new energy power generation. The present invention combines the static dynamic reactive power generator, the dynamic voltage restorer and the existing substation voltage and reactive power comprehensive control device to form a dynamic voltage and reactive power control system. The unit adjustment variation of the on-load voltage regulating transformer tap divides the voltage and reactive power plane into sixteen control areas, and each area corresponds to the corresponding control strategy. Through the coordinated control of the dynamic voltage and reactive power control system, the present invention suppresses the frequent fluctuation of grid voltage and reactive power caused by wind power and photovoltaic intermittent power generation, improves the comprehensive control level of grid voltage and reactive power, and is convenient for practical engineering applications. The comprehensive control of voltage and reactive power for new energy grid-connected power generation operation provides key technical support.

Description

A kind of idle composite coordination control system of line voltage of generation of electricity by new energy and method

Technical field

The invention belongs to the voltage & var control technical field that in electrical engineering, the new energy grid-connected power such as wind-powered electricity generation, photovoltaic runs, particularly a kind of idle composite coordination control system of line voltage and method containing generation of electricity by new energy.

Background technology

The basic performance element of electrical network automatic voltage control system (Automatic Voltage Control System-AVC) is transforming plant voltage reactive composite control apparatus (Voltage and Reactive Power Control System-VQC), VQC device is primarily of Capacitor banks and on-load tap-changing transformer composition, and the conversion (On Load Tap Changer-OLTC) of switching and on-load transformer tap changer that VQC system passes through nine-area control policy co-ordination control capacitor group is to realize line voltage and idle Comprehensive Control.And the subject matter existed in existing VQC device and " nine-zone diagram " control strategy is: the adjustment of on-load transformer tap changer and Capacitor banks is all have level to regulate, and regulate differential larger, be difficult to realize accurate control, in addition can produce the phenomenon of oscillation action during employing nine-area control strategy in some control area, cause traditional VQC device effectively can not meet the voltage power-less fluctuation problem caused when the intermittent new energy such as wind-powered electricity generation, photovoltaic electricity generation grid-connecting runs.

Power system reactive power voltage optimization controls to be the effective measures improving grid voltage quality, reduce network loss, improve power network safety operation.But improving constantly of the quality of power supply being required along with the large-scale development of the generation of electricity by new energy such as wind power generation, photovoltaic generation and user; the intermittent new energy being representative with wind-powered electricity generation, photovoltaic generating has also inevitably caused the power quality problem such as voltage fluctuation, voltage flicker frequently while alleviation Pressure on Energy, has had a strong impact on the normal operation of electrical network automatic voltage control system.Therefore, research and development are suitable for the voltage powerless control system of intermittent new energy electricity generation grid-connecting operation is very urgent and necessary.Given this, the present invention devises dynamic electric voltage powerless control system (Dynamic Voltage and Reactive Power Control System-DVQC), and correspondingly proposes a kind of idle composite coordination control method of line voltage containing generation of electricity by new energy.Its principle carries out cooperation control by the dynamic electric voltage idle composite coordination control method based on " 16 district figure " to the various voltage and reactive power compensation devices in DVQC thus solve to generate electricity by way of merging two or more grid systems due to intermittent new energy running the outstanding problem of the voltage power-less frequent fluctuation caused.The method is that the voltage & var control that in intelligent grid, new energy grid-connected power runs provides key technology support.

Summary of the invention

The present invention is directed to because intermittent new energy is generated electricity by way of merging two or more grid systems the outstanding power quality problem of the frequent voltage fluctuation, voltage flicker etc. that cause, propose a kind of idle composite coordination control system of line voltage and method of generation of electricity by new energy.

The idle composite coordination control system of line voltage of generation of electricity by new energy, this system is made up of on-load tap-changing transformer 2, Capacitor banks 3, silent oscillation dynamic reactive generator 4, dynamic electric voltage recovery device 5, first power amplification unit 6, second power amplification unit 7, the 3rd power amplification unit 8, the 4th power amplification unit 9 and voltage power-less composite coordination controller 1; Wherein,

Described voltage power-less composite coordination controller 1 is connected with on-load tap-changing transformer 2 by the first power amplification unit 6;

Described voltage power-less composite coordination controller 1 is connected with Capacitor banks 3 by the second power amplification unit 7;

Described voltage power-less composite coordination controller 1 is connected with silent oscillation dynamic reactive generator 4 by the 3rd power amplification unit 8;

Described voltage power-less composite coordination controller 1 is connected with dynamic electric voltage recovery device 5 by the 4th power amplification unit 9;

Described on-load tap-changing transformer 2 is connected with dynamic electric voltage recovery device 5;

Described Capacitor banks 3 is connected with dynamic electric voltage recovery device 5 with on-load tap-changing transformer 2 respectively with after the parallel connection of silent oscillation dynamic reactive generator 4;

Described first power amplification unit 6, second power amplification unit 7, the 3rd power amplification unit 8 and the 4th power amplification unit 9 are used for that the weak electric signal that voltage power-less composite coordination controller 1 sends action command is converted to forceful electric power signal and distribute to each device.

The idle composite coordination control method of line voltage of generation of electricity by new energy, the method comprises the following steps:

Step 1: voltage power-less composite coordination controller 1 carries out initialization, receives the information collected after initialization;

Step 2: voltage power-less composite coordination controller 1 is according to substation low-voltage side busbar voltage U ⁽⁰⁾with high-pressure side inject reactive power Q ⁽⁰⁾, judge that the voltage power-less running status of current system is in residing region in 16 district figure subregions;

Step 3: voltage power-less composite coordination controller 1 is region residing for the voltage power-less running status of current system, the control strategy corresponding according to this region in the information collected and 16 district figure control strategies sends instruction respectively to on-load tap-changing transformer 2, Capacitor banks 3, silent oscillation dynamic reactive generator 4 and dynamic electric voltage recovery device 5;

Step 4: on-load tap-changing transformer 2, Capacitor banks 3, silent oscillation dynamic reactive generator 4 and dynamic electric voltage recovery device 5, after the instruction that the idle composite coordination controller 1 of receiver voltage sends, carry out corresponding actions and realize the control of dynamic voltage power-less composite coordination.

Information described in step 1 comprises substation low-voltage side busbar voltage U ⁽⁰⁾; The reactive power Q that high-pressure side is injected ⁽⁰⁾; The same day on-load tap-changing transformer 2 tap action frequency N; The group number F of Capacitor banks can be dropped into _in, the group number F of Capacitor banks can be excised _out; The tap current gear k of on-load tap-changing transformer 2.

The concrete partitioned mode of 16 district figure described in step 2 is as follows:

One district: provincial characteristics $\left\{\begin{array}{c}Q\≤Q_O-{\mathrm{\ΔQ}}_q\\ U\≥U_O+{\mathrm{\ΔU}}_u\end{array}\right.;$

2nd district: provincial characteristics $\left\{\begin{array}{c}{Q}_O-{\mathrm{\&Delta;Q}}_q<Q\&le;Q_O\\ U\&GreaterEqual;U_O+{\mathrm{\&Delta;U}}_u\end{array}\right.;$

3rd district: provincial characteristics $\left\{\begin{array}{c}{Q}_O<Q<Q_O+{\mathrm{\&Delta;Q}}_q\\ U\&GreaterEqual;U_O+{\mathrm{\&Delta;U}}_u\end{array}\right.;$

4th district: provincial characteristics $\left\{\begin{array}{c}Q\&GreaterEqual;Q_O+{\mathrm{\&Delta;Q}}_q\\ U\&GreaterEqual;U_O+{\mathrm{\&Delta;U}}_u\end{array}\right.;$

5th district: provincial characteristics $\left\{\begin{array}{c}Q\&le;Q_O-{\mathrm{\&Delta;Q}}_q\\ U_O\&le;U<U_O+{\mathrm{\&Delta;U}}_u\end{array}\right.;$

6th district: provincial characteristics $\left\{\begin{array}{c}{Q}_O-{\mathrm{\&Delta;Q}}_q<Q\&le;Q_O\\ U_O\&le;U<U_O+{\mathrm{\&Delta;U}}_u\end{array}\right.;$

7th district: provincial characteristics $\left\{\begin{array}{c}{Q}_O<Q<Q_O+{\mathrm{\&Delta;Q}}_q\\ U_O<U<U_O+{\mathrm{\&Delta;U}}_u\end{array}\right.;$

8th district: provincial characteristics $\left\{\begin{array}{c}{Q}_O+{\mathrm{\&Delta;Q}}_q\&le;Q\\ U_O<U<U_O+{\mathrm{\&Delta;U}}_u\end{array}\right.;$

9th district: provincial characteristics $\left\{\begin{array}{c}{Q}_O-{\mathrm{\&Delta;Q}}_q\&GreaterEqual;Q\\ U_O-{\mathrm{\&Delta;U}}_u<U<U_O\end{array}\right.;$

Tenth district: provincial characteristics $\left\{\begin{array}{c}{Q}_O-{\mathrm{\&Delta;Q}}_q<Q\&le;Q_O\\ U_O-{\mathrm{\&Delta;U}}_u<U<U_O\end{array}\right.;$

11st district: provincial characteristics $\left\{\begin{array}{c}{Q}_O<Q<Q_O+{\mathrm{\&Delta;Q}}_q\\ U_O-{\mathrm{\&Delta;U}}_u<U\&le;U_O\end{array}\right.;$

No.12 District: provincial characteristics $\left\{\begin{array}{c}Q\&GreaterEqual;Q_O+{\mathrm{\&Delta;Q}}_q\\ U_O-{\mathrm{\&Delta;U}}_u<U\&le;U_O\end{array}\right.;$

13rd district: provincial characteristics $\left\{\begin{array}{c}Q\&le;Q_O-{\mathrm{\&Delta;Q}}_q\\ U\&le;U_O-{\mathrm{\&Delta;U}}_u\end{array}\right.;$

14th district: provincial characteristics $\left\{\begin{array}{c}{Q}_O-{\mathrm{\&Delta;Q}}_q<Q\&le;Q_O\\ U\&le;U_O-{\mathrm{\&Delta;U}}_u\end{array}\right.;$

15th district: provincial characteristics $\left\{\begin{array}{c}{Q}_O<Q<Q_O+{\mathrm{\&Delta;Q}}_q\\ U\&le;U_O-{\mathrm{\&Delta;U}}_u\end{array}\right.;$

16th district: provincial characteristics $\left\{\begin{array}{c}Q\&GreaterEqual;Q_O+{\mathrm{\&Delta;Q}}_q\\ U\&le;U_O-{\mathrm{\&Delta;U}}_u\end{array}\right.;$

Wherein, O point is the optimized operation state of electrical network, U _ofor the voltage of optimized operation state, Q _ofor the reactive power of optimized operation state, Q is the reactive power under system current operating conditions, and U is the voltage under system current operating conditions, Δ Q _qfor the idle work variable quantity that switching one group capacitor causes, Δ U _uone grade of voltage variety caused is changed for regulating the tap of on-load tap-changing transformer 2.

Described in step 2,16 district figure control strategies are:

One district's strategy:

(1) if F _out≠ 0, calculate M.m=|Q ⁽⁰⁾-Q _o|/Δ Q _q.If (i) M≤F _out, voltage power-less composite coordination controller 1 sends instruction excision M group capacitor; (ii) if M>F _out, voltage power-less composite coordination controller 1 sends instruction excision F _outgroup capacitor;

(2) if F _out=0, voltage power-less composite coordination controller 1 sends instruction makes silent oscillation dynamic reactive generator 4 send reactive power compensation amount Q _sVG=Q ⁽⁰⁾-Q _o;

Two district's strategies:

(1) if Q _o-Q ⁽⁰⁾>Q _ε, enter idle controlling unit, voltage power-less composite coordination controller 1 sends instruction makes silent oscillation dynamic reactive generator 4 send reactive power compensation amount Q _sVG=Q ⁽⁰⁾-Q _o;

(2) if Q _o-Q ⁽⁰⁾≤ Q _ε, enter voltage control link, if (i) k=k _maxand N=N _maxin have an establishment at least, voltage power-less composite coordination controller 1 sends instruction makes dynamic electric voltage recovery device 5 send voltage compensation U _dVR=U _o-U ⁽⁰⁾; (ii) if k<k _maxand N<N _max, voltage power-less composite coordination controller 1 sends instruction makes the tap of on-load tap-changing transformer 2 rise one grade;

Three district's strategies:

(1) if k=k _maxand N=N _maxin have an establishment at least, voltage power-less composite coordination controller 1 sends instruction makes dynamic electric voltage recovery device 5 produce voltage compensation quantity U _dVR=U _o-U ⁽⁰⁾;

(2) if k<k _maxand N<N _max, voltage power-less composite coordination controller 1 sends instruction makes the tap of on-load tap-changing transformer 2 rise one grade;

Four district's strategies:

(1) if k=k _maxand N=N _maxin have an establishment at least, voltage power-less composite coordination controller 1 sends instruction makes dynamic electric voltage recovery device 5 produce voltage compensation quantity U _dVR=U _o-U ⁽⁰⁾;

(2) if k<k _maxand N<N _max, voltage power-less composite coordination controller 1 sends instruction makes the tap of on-load tap-changing transformer 2 rise one grade;

Five district's strategies:

(1) if F _out≠ 0, M.m=|Q ⁽⁰⁾-Q _o|/Δ Q _qif, (i) M≤F _out, voltage power-less composite coordination controller 1 sends instruction excision M group capacitor; (ii) if M>F _out, voltage power-less composite coordination controller 1 sends instruction excision F _outgroup capacitor;

(2) if F _out=0, voltage power-less composite coordination controller 1 sends instruction makes silent oscillation dynamic reactive generator 4 send reactive power compensation amount Q _sVG=Q ⁽⁰⁾-Q _o;

Six district's strategies:

(1) if Q _o-Q ⁽⁰⁾>Q _ε, enter idle controlling unit, voltage power-less composite coordination controller 1 sends instruction makes silent oscillation dynamic reactive generator 4 send reactive power compensation amount Q _sVG=Q ⁽⁰⁾-Q _o;

(2) if Q _o-Q ⁽⁰⁾≤ Q _ε, enter voltage control link, voltage power-less composite coordination controller 1 sends instruction makes dynamic electric voltage recovery device 5 produce voltage compensation quantity U _dVR=U _o-U ⁽⁰⁾;

Seven district's strategies:

Voltage power-less composite coordination controller 1 sends instruction makes dynamic electric voltage recovery device 5 produce voltage compensation quantity U _dVR=U _o-U ⁽⁰⁾;

Eight district's strategies:

Voltage power-less composite coordination controller 1 sends instruction makes dynamic electric voltage recovery device 5 produce voltage compensation quantity U _dVR=U _o-U ⁽⁰⁾;

Nine district's strategies:

Voltage power-less composite coordination controller 1 sends instruction makes dynamic electric voltage recovery device 5 produce voltage compensation quantity U _dVR=U _o-U ⁽⁰⁾;

Ten district's strategies:

Voltage power-less composite coordination controller 1 sends instruction makes dynamic electric voltage recovery device 5 produce voltage compensation quantity U _dVR=U _o-U ⁽⁰⁾;

11 district's strategies:

(1) if Q ⁽⁰⁾-Q _o>Q _ε, enter idle controlling unit, voltage power-less composite coordination controller 1 sends instruction makes silent oscillation dynamic reactive generator 4 send reactive power compensation amount Q _sVG=Q ⁽⁰⁾-Q _o;

(2) if Q ⁽⁰⁾-Q _o≤ Q _ε, enter voltage control link.Voltage power-less composite coordination controller 1 sends instruction makes dynamic electric voltage recovery device 5 produce voltage compensation quantity U _dVR=U _o-U ⁽⁰⁾;

No.12 District strategy:

(1) if F _in=0, voltage power-less composite coordination controller 1 sends instruction makes silent oscillation dynamic reactive generator 4 send reactive power compensation amount Q _sVG=Q ⁽⁰⁾-Q _o;

(2) if F _in≠ 0, calculate M.m=|Q ⁽⁰⁾-Q _o|/Δ Q _q;

If (i) M≤F _in, voltage power-less composite coordination controller 1 sends instruction and drops into M group capacitor;

(ii) if M>F _in, voltage power-less composite coordination controller 1 sends instruction and drops into F _ingroup capacitor;

13 district's strategies:

(1) if k=k _minand N=N _maxin have an establishment at least, voltage power-less composite coordination controller 1 sends instruction makes dynamic electric voltage recovery device 5 produce voltage compensation quantity U _dVR=U _o-U ⁽⁰⁾;

(2) if k ≠ k _minand N ≠ N _max, voltage power-less composite coordination controller 1 sends instruction makes the tap of on-load tap-changing transformer 2 fall one grade;

14 district's strategies:

(1) if k=k _minand N=N _maxin have an establishment at least, voltage power-less composite coordination controller 1 sends instruction makes dynamic electric voltage recovery device 5 produce voltage compensation quantity U _dVR=U _o-U ⁽⁰⁾;

(2) if k ≠ k _minand N ≠ N _max, voltage power-less composite coordination controller 1 sends instruction makes the tap of on-load tap-changing transformer 2 fall one grade;

15 district's strategies:

(1) if Q ⁽⁰⁾-Q _o>Q _ε, enter idle controlling unit, voltage power-less composite coordination controller 1 sends instruction makes silent oscillation dynamic reactive generator 4 send reactive power compensation amount Q _sVG=Q ⁽⁰⁾-Q _o;

(2) if Q ⁽⁰⁾-Q _o≤ Q _ε, enter voltage control link, if (i) k=k _minand N=N _maxin have an establishment at least, voltage power-less composite coordination controller 1 sends instruction makes dynamic electric voltage recovery device 5 produce voltage compensation quantity U _dVR=U _o-U ⁽⁰⁾; (ii) if k ≠ k _minand N ≠ N _max, voltage power-less composite coordination controller 1 sends instruction makes the tap of on-load tap-changing transformer 2 fall one grade;

16 district's strategies:

(1) if F _in=0, voltage power-less composite coordination controller 1 sends instruction makes silent oscillation dynamic reactive generator 4 send reactive power compensation amount Q _sVG=Q ⁽⁰⁾-Q _o;

(2) if F _in≠ 0, calculate M.m=|Q ⁽⁰⁾-Q _o|/Δ Q _q.If (i) M≤F _in, voltage power-less composite coordination controller 1 sends instruction and drops into M group capacitor; (ii) if M>F _in, voltage power-less composite coordination controller 1 sends instruction and drops into F _ingroup capacitor;

Wherein, total group of number of Capacitor banks 3 is F _in+ F _out; M.m is | Q ⁽⁰⁾-Q _o|/Δ Q _qnumerical value, wherein M representative | Q ⁽⁰⁾-Q _o|/Δ Q _qinteger part, m represent | Q ⁽⁰⁾-Q _o|/Δ Q _qfractional part; The tap upper limit position of on-load tap-changing transformer 2 is k _max, lower position is k _min.

Beneficial effect of the present invention: the present invention adopts the idle composite coordination control system of line voltage and the method for a kind of generation of electricity by new energy proposed, voltage power-less dynamic adjustments is carried out for the electrical network containing the generating of the intermittent new energy such as wind-powered electricity generation, photovoltaic, effectively can solve the outstanding problem of the voltage power-less frequent fluctuation caused due to the randomness of wind-powered electricity generation, photovoltaic, fluctuation, intermittence, effectively can realize the Real-time Balancing of reactive power, guarantee that voltage maintains normal level.Overcome the phenomenon of the oscillation action that existing VQC device and nine-area control strategy may cause simultaneously, the Dynamic controlling that line voltage can be made idle is more flexible, the optimal load flow being conducive to realizing electrical network runs, and improves the efficiency of generating electricity by way of merging two or more grid systems of the intermittent new energy such as wind-powered electricity generation, photovoltaic generating.The voltage power-less that the method significantly can suppress the intermittent new energy such as wind-powered electricity generation, photovoltaic electricity generation grid-connecting to run and cause fluctuates, improve line voltage reactive comprehensive level of control, improve electric network security, stability, reliability and economy that the intermittent new energy such as wind-powered electricity generation, photovoltaic in intelligent grid is generated electricity by way of merging two or more grid systems when running.In a word, the method is particularly suitable for, containing the idle cooperation control of line voltage of intermittent new energy generating, being convenient to practical engineering application, and the voltage and reactive power integrative control run for new energy grid-connected power in intelligent grid provides key technology support.

Accompanying drawing explanation

Fig. 1. containing the wind-electricity integration power generation system structure schematic diagram of DVQC in embodiment;

" 16 district figure " control strategy principle schematic in Fig. 2 embodiment;

Dynamic electric voltage powerless control system DVQC operation principle flow chart in Fig. 3 embodiment;

Fig. 4. the wind farm wind velocity change curve in embodiment under Wind speed up operating mode;

Wind energy turbine set in Fig. 5 embodiment under Wind speed up operating mode is gained merit change curve;

Change curve contrast that wind energy turbine set in Fig. 6 embodiment under Wind speed up operating mode before and after DVQC regulates is idle;

Wind energy turbine set voltage change curve contrast in Fig. 7 embodiment under Wind speed up operating mode before and after DVQC regulates;

The wind farm wind velocity change curve under wind speed operating mode is surveyed in Fig. 8 embodiment;

The wind energy turbine set of surveying in Fig. 9 embodiment under wind speed operating mode is gained merit change curve;

The idle change curve contrast of the wind energy turbine set of front and back is regulated through DVQC under surveying wind speed operating mode in Figure 10 embodiment;

The wind energy turbine set voltage change curve of front and back is regulated to contrast through DVQC under surveying wind speed operating mode in Figure 11 embodiment;

Wherein, 1-voltage power-less composite coordination controller, 2-on-load tap-changing transformer, 3-Capacitor banks, 4-silent oscillation dynamic reactive generator, 5-dynamic electric voltage recovery device, 6-first power amplification unit, 7-second power amplification unit, 8-the 3rd power amplification unit, 9-the 4th power amplification unit.

Embodiment

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

As shown in Figure 1, existing transforming plant voltage reactive composite control apparatus VQC comprises Capacitor banks and on-load tap-changing transformer, and the present invention is by silent oscillation dynamic reactive generator (Static Var Generator-SVG), dynamic electric voltage recovery device (Dynamic Voltage Restorer-DVR) combines with existing transforming plant voltage reactive composite control apparatus VQC and constitutes dynamic electric voltage powerless control system DVQC, wherein, on-load tap-changing transformer 2 is connected with dynamic electric voltage recovery device 5, Capacitor banks 3 is connected with dynamic electric voltage recovery device 5 with on-load tap-changing transformer 2 respectively with after the parallel connection of silent oscillation dynamic reactive generator 4, first power amplification unit 6, second power amplification unit 7, 3rd power amplification unit 8 and the 4th power amplification unit 9 are used for that the weak electric signal that voltage power-less composite coordination controller 1 sends action command is converted to forceful electric power signal and distribute to each device.They are all connected by power amplification unit the reception and the information feed back that realize order with voltage power-less composite coordination controller 1, and command signal carries out the conversion between weak electric signal and forceful electric power signal by power amplification unit.This system utilizes the unit of the idle optimized operation state of line voltage and VQC device (Capacitor banks, on-load transformer tap changer) to regulate variable quantity, and voltage and idle plane are divided into 16 controlled areas, the corresponding corresponding control strategy of regional.

Control strategy principle schematic that Fig. 2 gives " 16 district figure ", control strategy is according to the voltage of system Real-Time Monitoring, idle judgement electrical network current operating conditions region, then control with the cycle in compensating power vacancy and voltage deviation long according to the corresponding control strategy in this region to discrete type voltage and reactive power control systems such as on-load tap-changing transformer 2 and Capacitor banks 3, the flat part of vary within wide limits, control the dynamic electric voltage reactive-load adjusting device such as dynamic electric voltage recovery device 5 and silent oscillation dynamic reactive generator 4 shorter with the cycle in compensating power vacancy and voltage deviation, the dynamic fluctuation part that amplitude is little, thus real-time and precise realize the idle control of dynamic electric voltage, improve quality of voltage, reduce network loss, be conducive to Optimum Reactive Power Flow distribution, thus obtain good technical economic benefit.

In the 16 district figure control strategies of dynamic electric voltage control system DVQC, its desirable control objectives will be no longer a region, but a point, the voltage power-less parameter of this operating point is the voltage power-less value under electrical network optimized operation state, and calculating link by electrical network optimal load flow provides.This control program can reach control objectives more accurately, realizes the optimization of reactive power flow, guarantees quality of voltage.Wherein, O point is the optimized operation state of electrical network, U _ofor the voltage of optimized operation state, Q _ofor the reactive power of optimized operation state, Q is the reactive power under system current operating conditions, and U is the voltage under system current operating conditions, Δ Q _qfor the idle work variable quantity that switching one group capacitor causes, Δ U _uone grade of voltage variety caused is changed for regulating the tap of on-load tap-changing transformer." 16 district figure " control strategy with O point for control objectives, according to Δ U _u, Δ Q _qvoltage power-less plane marks off 16 regions, Δ U _u, Δ Q _qvalue the change of the difference of the tap joint position along with on-load tap-changing transformer and low-pressure side bus voltage is changed.

DVQC System Working Principle flow chart as indicated at 3.At every turn before DVQC system judges operating point interval and sends corresponding control strategy, first to obtain following information by electrical network remote signalling, telemetry function:

(1) substation low-voltage side busbar voltage U ⁽⁰⁾;

(2) high-pressure side inject reactive power Q ⁽⁰⁾;

(3) the tap joint position k(of on-load tap-changing transformer sets the tap upper limit position of on-load tap-changing transformer as k _max, lower position is k _min);

(4) Capacitor banks number F can be excised _outand Capacitor banks number F can be dropped into _in;

(5) the tap action frequency on the same day of on-load tap-changing transformer is that N(tap maximum actuation every day number of times is restricted to N _max)

Adjustment tap and the mathematical relationship of opening-closing capacitor bank on voltage and idle impact are:

(1) voltage variety caused by tap-c hange control one grade of on-load tap-changing transformer is such as formula (1):

ΔU _u=(Δk/k)U' (1)

Wherein, Δ k is the gear change amount between adjacent taps, is fixed value for same transformer; K is for regulating the gear residing for front tap; U' is the low-pressure side bus magnitude of voltage before tap-c hange control.

(2) tap-c hange control one grade of idle work variable quantity caused of on-load tap-changing transformer is such as formula (2):

ΔQ _u=(Δk/k)(2+Δk/k)B _CNU' ² (2)

Wherein, B _cNit is the specified susceptance value of a group capacitor.

(3) voltage variety that causes of switching one group capacitor is such as formula shown in (3).

ΔU _q=U'*(Q _CN/S _SC) (3)

Wherein, Q _cNit is the rated capacity of a group capacitor; S _sCmain transformer low-pressure side capacity of short circuit.

(4) idle work variable quantity that causes of switching one group capacitor is such as formula shown in (4).

ΔQ _q=B _CNU' ² (4)

3, " 16 district figure " control strategy is described in detail as follows:

Here M.m represents a numerical value, and M represents | Q ⁽⁰⁾-Q _o|/Δ Q _qinteger part, m represent | Q ⁽⁰⁾-Q _o|/Δ Q _qfractional part; Q ⁽⁰⁾, U ⁽⁰⁾represent idle and magnitude of voltage initial in this control cycle of DVQC system, Q ⁽¹⁾, U ⁽¹⁾represent the idle and magnitude of voltage of DVQC system after this control cycle regulates.

(1) a district: its provincial characteristics $\left\{\begin{array}{c}Q\&le;Q_O-{\mathrm{\&Delta;Q}}_q\\ U\&GreaterEqual;U_O+{\mathrm{\&Delta;U}}_u\end{array}\right.$

First the excised group number F of the section of sentencing Capacitor banks 3 _outwhether be 0;

If 1. F _out≠ 0, then preferentially should excise capacitor.By | Q _o-Q ⁽⁰⁾|/Δ Q _q=M.m, can excise M group capacitor.Judge again should excise Capacitor banks number M and Capacitor banks number F can be excised _outrelation.

If (i) M≤F _out, then can excise Capacitor banks and count up to and all can enough meet the requirement should excising Capacitor banks number, voltage power-less composite coordination controller 1 sends the instruction of excision M group capacitor.The change in voltage caused by excision M group capacitor thus cause operation of power networks point from (Q ⁽⁰⁾, U ⁽⁰⁾) become (Q ⁽¹⁾, U ⁽¹⁾), wherein $\left\{\begin{array}{c}{Q}^{\left(1\right)}=Q^{\left(0\right)}=M*{\mathrm{\&Delta;Q}}_q\\ U^{\left(1\right)}=U^{\left(0\right)}+\mathrm{\&Delta;U}\end{array}\right.$

(ii) if M>F _out, then can excise Capacitor banks number can not meet the requirement should excising Capacitor banks number completely.Voltage power-less composite coordination controller 1 can only send excision F _outgroup capacitor instruction.Excision F _outgroup capacitor causes corresponding change in voltage operation of power networks state will from (Q ⁽⁰⁾, U ⁽⁰⁾) become (Q ⁽¹⁾, U ⁽¹⁾), wherein $\left\{\begin{array}{c}{Q}^{\left(1\right)}=Q^{\left(0\right)}=F_{\mathrm{out}}*{\mathrm{\&Delta;Q}}_q\\ U^{\left(1\right)}=U^{\left(0\right)}+\mathrm{\&Delta;U}\end{array}\right.$

If 2. F _out=0, can not excise capacitor, then should preferentially allow silent oscillation dynamic reactive generator 4 send capacitive reactive power, its value size is Q _sVG=Q ⁽⁰⁾-Q _o, correspondingly can cause voltage variety Δ U=-(U ⁽⁰⁾/ S _sC) * | Q _sVG|.Operation of power networks state will from (Q ⁽⁰⁾, U ⁽⁰⁾) become (Q ⁽¹⁾, U ⁽¹⁾), wherein $\left\{\begin{array}{c}{Q}^{\left(1\right)}=Q_O\\ U^{\left(1\right)}=U^{\left(0\right)}+\mathrm{\&Delta;U}\end{array}\right.$

(2) 2nd district: its provincial characteristics $\left\{\begin{array}{c}{Q}_O-{\mathrm{\&Delta;Q}}_q<Q\&le;Q_O\\ U\&GreaterEqual;U_O+{\mathrm{\&Delta;U}}_u\end{array}\right.$

First Q is judged _o-Q ⁽⁰⁾>Q _εset up no.Q _εfor the reactive power adjusting deviation amount allowed in actual operating mode.

1. Q _o-Q ⁽⁰⁾>Q _ε, then idle controlling unit is entered.Because idle difference is less than the idle work variable quantity that switching one group capacitor causes, so without the need to opening-closing capacitor bank 3, directly make silent oscillation dynamic reactive generator 4 send capacitive reactive power, its value is Q _sVG=Q ⁽⁰⁾-Q _o, correspondingly cause voltage variety to be Δ U=(-U ⁽⁰⁾/ S _sC) * | Q _sVG|, operation of power networks state will from (Q ⁽⁰⁾, U ⁽⁰⁾) become (Q ⁽¹⁾, U ⁽¹⁾), wherein $\left\{\begin{array}{c}{Q}^{\left(1\right)}=Q_O\\ U^{\left(1\right)}=U^{\left(0\right)}+\mathrm{\&Delta;U}\end{array}\right.$

2. Q _o-Q ⁽⁰⁾≤ Q _ε, enter voltage control link.The tap upshift step-down of on-load tap-changing transformer 2 need be regulated, now need the tap joint position k judging on-load tap-changing transformer 2 whether to be in lower limit k _minand whether action frequency N reaches maximum permission action frequency N _max.

If (i) k=k _maxand N=N _maxin have an establishment at least, then show that the tap of on-load tap-changing transformer 2 is non-adjustable.Dynamic electric voltage recovery device 5 action now should be made to produce voltage compensation quantity, and its value is U _dVR=U _o-U ⁽⁰⁾, operation of power networks state will from (Q ⁽⁰⁾, U ⁽⁰⁾) become (Q ⁽¹⁾, U ⁽¹⁾), wherein $\left\{\begin{array}{c}{Q}^{\left(1\right)}=Q_O\\ U^{\left(1\right)}=U_O\end{array}\right.$

(ii) if k<k _maxand N<N _max, then the tap upshift step-down of on-load tap-changing transformer 2 is regulated.Thus voltage variety is Δ U _u=-(Δ k/k) U ⁽⁰⁾, owing to upshifing, the idle work variable quantity caused is operation of power networks state will from (Q ⁽⁰⁾, U ⁽⁰⁾) become (Q ⁽¹⁾, U ⁽¹⁾), wherein $\left\{\begin{array}{c}{Q}^{\left(1\right)}=Q^{\left(0\right)}+\mathrm{\&Delta;Q}\\ U^{\left(1\right)}=U^{\left(0\right)}+{\mathrm{\&Delta;U}}_u\end{array}\right.$

(3) 3rd district: its provincial characteristics $\left\{\begin{array}{c}{Q}_O<Q<Q_O+{\mathrm{\&Delta;Q}}_q\\ U\&GreaterEqual;U_O+{\mathrm{\&Delta;U}}_u\end{array}\right.$

First, need judge whether the tap joint position k of on-load tap-changing transformer 2 is in lower limit k _maxand whether action frequency N reaches maximum permission action frequency N _max.

If 1. k=k _maxand N=N _maxin have an establishment at least, then the tap of on-load tap-changing transformer 2 can not carry out upshift step-down again.Now should allow and directly allow dynamic electric voltage recovery device 5 directly produce voltage compensation quantity U _dVR=U _o-U ⁽⁰⁾, operation of power networks state will from (Q ⁽⁰⁾, U ⁽⁰⁾) become (Q ⁽¹⁾, U ⁽¹⁾), wherein $\left\{\begin{array}{c}{Q}^{\left(1\right)}=Q^{\left(0\right)}\\ U^{\left(1\right)}=U^{\left(0\right)}+U_{\mathrm{DVR}}\end{array}\right.$

If 2. k<k _maxand N<N _max, then the tap upshift step-down of on-load tap-changing transformer 2 can be made.

The tap of on-load tap-changing transformer 2 rises one grade and causes voltage variety to be Δ U _u=-(Δ k/k) U ⁽⁰⁾, corresponding idle work variable quantity is operation of power networks state will from (Q ⁽⁰⁾, U ⁽⁰⁾) become (Q ⁽¹⁾, U ⁽¹⁾), wherein $\left\{\begin{array}{c}{Q}^{\left(1\right)}=Q^{\left(0\right)}+\mathrm{\&Delta;Q}\\ U^{\left(1\right)}=U^{\left(0\right)}+{\mathrm{\&Delta;U}}_u\end{array}\right.$

(4) 4th district: its provincial characteristics $\left\{\begin{array}{c}Q\&GreaterEqual;Q_O+{\mathrm{\&Delta;Q}}_q\\ U\&GreaterEqual;U_O+{\mathrm{\&Delta;U}}_u\end{array}\right.$

First, need judge whether the tap joint position k of on-load tap-changing transformer 2 is in lower limit k _maxand whether action frequency N reaches maximum permission action frequency N _max.

If 1. k=k _maxand N=N _maxin have an establishment at least, then the tap of on-load tap-changing transformer 2 can not carry out upshift step-down again.Dynamic electric voltage recovery device 5 now should be directly allowed directly to produce voltage compensation quantity U _dVR=U _o-U ⁽⁰⁾, operation of power networks state will from (Q ⁽⁰⁾, U ⁽⁰⁾) become (Q ⁽¹⁾, U ⁽¹⁾), wherein $\left\{\begin{array}{c}{Q}^{\left(1\right)}=Q^{\left(0\right)}\\ U^{\left(1\right)}=U^{\left(0\right)}+U_{\mathrm{DVR}}\end{array}\right.$

If 2. k<k _maxand N<N _max, then the tap upshift step-down of on-load tap-changing transformer 2 is made.

The tap of on-load tap-changing transformer 2 rises one grade and causes voltage variety to be Δ U _u=-(Δ k/k) U ⁽⁰⁾, corresponding idle work variable quantity is operation of power networks state will from (Q ⁽⁰⁾, U ⁽⁰⁾) become (Q ⁽¹⁾, U ⁽¹⁾), wherein $\left\{\begin{array}{c}{Q}^{\left(1\right)}=Q^{\left(0\right)}+\mathrm{\&Delta;Q}\\ U^{\left(1\right)}=U^{\left(0\right)}+{\mathrm{\&Delta;U}}_u\end{array}\right.$

(5) 5th district: its provincial characteristics $\left\{\begin{array}{c}Q\&le;Q_O-{\mathrm{\&Delta;Q}}_q\\ U_O\&le;U<U_O+{\mathrm{\&Delta;U}}_u\end{array}\right.$

First the excised group number F of the section of sentencing Capacitor banks 3 _outwhether be 0;

If 1. F _out≠ 0, then preferentially should excise capacitor.By | Q _o-Q ⁽⁰⁾| Δ Q _q=M.m, can excise M group capacitor.Judge again should excise Capacitor banks number M and Capacitor banks number F can be excised _outrelation.

If (i) M≤F _out, then can excise Capacitor banks and count up to and all can enough meet the requirement should excising Capacitor banks number, voltage power-less composite coordination controller 1 sends the instruction of excision M group capacitor.The change in voltage caused by excision M group capacitor thus cause operation of power networks point from (Q ⁽⁰⁾, U ⁽⁰⁾) become (Q ⁽¹⁾, U ⁽¹⁾), wherein $\left\{\begin{array}{c}{Q}^{\left(1\right)}=Q^{\left(0\right)}+M*{\mathrm{\&Delta;Q}}_q\\ U^{\left(1\right)}=U^{\left(0\right)}+\mathrm{\&Delta;U}\end{array}\right.$

(ii) if M>F _out, then can excise Capacitor banks number can not meet the requirement should excising Capacitor banks number completely.Voltage power-less composite coordination controller 1 can only send excision F _outgroup capacitor instruction.Excision F _outgroup capacitor causes corresponding change in voltage operation of power networks state will from (Q ⁽⁰⁾, U ⁽⁰⁾) become (Q ⁽¹⁾, U ⁽¹⁾), wherein $\left\{\begin{array}{c}{Q}^{\left(1\right)}=Q^{\left(0\right)}+F_{\mathrm{out}}*{\mathrm{\&Delta;Q}}_q\\ U^{\left(1\right)}=U^{\left(0\right)}+\mathrm{\&Delta;U}\end{array}\right.$

If 2. F _out=0, can not excise capacitor, then should preferentially allow silent oscillation dynamic reactive generator 4 send capacitive reactive power, its value size is Q _sVG=Q ⁽⁰⁾-Q _o, correspondingly can cause voltage variety Δ U=-(U ⁽⁰⁾/ S _sC) * | Q _sVG|.Operation of power networks state will from (Q ⁽⁰⁾, U ⁽⁰⁾) become (Q ⁽¹⁾, U ⁽¹⁾), wherein $\left\{\begin{array}{c}{Q}^{\left(1\right)}=Q_O\\ U^{\left(1\right)}=U^{\left(0\right)}+\mathrm{\&Delta;U}\end{array}\right.$

(6) 6th district: its provincial characteristics $\left\{\begin{array}{c}{Q}_O-{\mathrm{\&Delta;Q}}_q<Q\&le;Q_O\\ U_O\&le;U<U_O+{\mathrm{\&Delta;U}}_u\end{array}\right.$

First Q is judged _o-Q ⁽⁰⁾>Q _εset up no.

If 1. Q _o-Q ⁽⁰⁾>Q _ε, then idle controlling unit is entered.First allow silent oscillation dynamic reactive generator 4 send capacitive reactive power, its value is Q _sVG=Q ⁽⁰⁾-Q _o, cause correspondingly voltage variety operation of power networks state will from (Q ⁽⁰⁾, U ⁽⁰⁾) become (Q ⁽¹⁾, U ⁽¹⁾), wherein $\left\{\begin{array}{c}{Q}^{\left(1\right)}=Q_O\\ U^{\left(1\right)}=U^{\left(0\right)}+\mathrm{\&Delta;U}\end{array}\right.$

If 2. Q _o-Q ⁽⁰⁾≤ Q _ε, enter voltage control link.Directly make dynamic electric voltage recovery device 5 action, make it produce voltage compensation quantity U _dVR=U _o-U ⁽⁰⁾, operation of power networks state will from (Q ⁽⁰⁾, U ⁽⁰⁾) become (Q ⁽¹⁾, U ⁽¹⁾), wherein $\left\{\begin{array}{c}{Q}^{\left(1\right)}=Q_O\\ U^{\left(1\right)}=U_O\end{array}\right.$

(7) 7th district: its provincial characteristics $\left\{\begin{array}{c}{Q}_O<Q<Q_O+{\mathrm{\&Delta;Q}}_q\\ U_O<U<U_O+{\mathrm{\&Delta;U}}_u\end{array}\right.$

Directly make dynamic electric voltage recovery device 5 action, make it produce voltage compensation quantity U _dVR=U _o-U ⁽⁰⁾, operation of power networks state will from (Q ⁽⁰⁾, U ⁽⁰⁾) become (Q ⁽¹⁾, U ⁽¹⁾), wherein $\left\{\begin{array}{c}{Q}^{\left(1\right)}=Q^{\left(0\right)}\\ U^{\left(1\right)}=U_O\end{array}\right.$

(8) 8th district: its provincial characteristics $\left\{\begin{array}{c}{Q}_O+{\mathrm{\&Delta;Q}}_q\&le;Q\\ U_O<U<U_O+{\mathrm{\&Delta;U}}_u\end{array}\right.$

Directly make dynamic electric voltage recovery device 5 action, make it produce voltage compensation quantity U _dVR=U _o-U ⁽⁰⁾, operation of power networks state will from (Q ⁽⁰⁾, U ⁽⁰⁾) become (Q ⁽¹⁾, U ⁽¹⁾), wherein $\left\{\begin{array}{c}{Q}^{\left(1\right)}=Q^{\left(0\right)}\\ U^{\left(1\right)}=U_O\end{array}\right.$

(9) 9th district: its provincial characteristics $\left\{\begin{array}{c}{Q}_O-{\mathrm{\&Delta;Q}}_q\&GreaterEqual;Q\\ U_O-{\mathrm{\&Delta;U}}_u<U<U_O\end{array}\right.$

Directly make dynamic electric voltage recovery device 5 action, make it produce voltage compensation quantity U _dVR=U _o-U ⁽⁰⁾, operation of power networks state will from (Q ⁽⁰⁾, U ⁽⁰⁾) become (Q ⁽¹⁾, U ⁽¹⁾), wherein $\left\{\begin{array}{c}{Q}^{\left(1\right)}=Q^{\left(0\right)}\\ U^{\left(1\right)}=U_O\end{array}\right.$

(10) tenth district: its provincial characteristics $\left\{\begin{array}{c}{Q}_O-{\mathrm{\&Delta;Q}}_q<Q\&le;Q_O\\ U_O-{\mathrm{\&Delta;U}}_u<U<U_O\end{array}\right.$

Directly make dynamic electric voltage recovery device 5 action, make it produce voltage compensation quantity U _dVR=U _o-U ⁽⁰⁾, operation of power networks state will from (Q ⁽⁰⁾, U ⁽⁰⁾) become (Q ⁽¹⁾, U ⁽¹⁾), wherein $\left\{\begin{array}{c}{Q}^{\left(1\right)}=Q^{\left(0\right)}\\ U^{\left(1\right)}=U_O\end{array}\right.$

(11) 11st district: its provincial characteristics $\left\{\begin{array}{c}{Q}_O<Q<Q_O+{\mathrm{\&Delta;Q}}_q\\ U_O-{\mathrm{\&Delta;U}}_u<U\&le;U_O\end{array}\right.$

First Q is judged ⁽⁰⁾-Q _o>Q _εset up no.

If 1. Q ⁽⁰⁾-Q _o>Q _ε, then idle controlling unit is entered.Allow silent oscillation dynamic reactive generator 4 send lagging reactive power, its value is Q _sVG=Q ⁽⁰⁾-Q _o, cause corresponding voltage variety to be operation of power networks state will from (Q ⁽⁰⁾, U ⁽⁰⁾) become (Q ⁽¹⁾, U ⁽¹⁾), wherein $\left\{\begin{array}{c}{Q}^{\left(1\right)}=Q_O\\ U^{\left(1\right)}=U^{\left(0\right)}+\mathrm{\&Delta;U}\end{array}\right.$

If 2. Q ⁽⁰⁾-Q _o≤ Q _ε, then voltage control link is entered.Dynamic electric voltage recovery device 5 action is made to produce voltage compensation quantity U _dVR=U _o-U ⁽⁰⁾, operation of power networks state will from (Q ⁽⁰⁾, U ⁽⁰⁾) become (Q ⁽¹⁾, U ⁽¹⁾), wherein $\left\{\begin{array}{c}{Q}^{\left(1\right)}=Q_O\\ U^{\left(1\right)}=U_O\end{array}\right.$

(12) No.12 District: its provincial characteristics $\left\{\begin{array}{c}Q\&GreaterEqual;Q_O+{\mathrm{\&Delta;Q}}_q\\ U_O-{\mathrm{\&Delta;U}}_u<U\&le;U_O\end{array}\right.$

First judge that capacitor can drop into group number F _inwhether be 0.

If 1. F _in=0, then illustrate that capacitorless can be thrown.Need to make silent oscillation dynamic reactive generator 4 send lagging reactive power, its value is Q _sVG=Q ⁽⁰⁾-Q _o, cause corresponding voltage variety operation of power networks state will from (Q ⁽⁰⁾, U ⁽⁰⁾) become (Q ⁽¹⁾, U ⁽¹⁾), wherein $\left\{\begin{array}{c}{Q}^{\left(1\right)}=Q_O\\ U^{\left(1\right)}=U^{\left(0\right)}+\mathrm{\&Delta;U}\end{array}\right.$

If 2. F _in≠ 0, then can drop into Capacitor banks 3.By | Q _o-Q ⁽⁰⁾|/Δ Q _q=M.m known needs drops into M group capacitor.

If (i) M≤F _in, then can drop into Capacitor banks and count up to and all can enough meet the requirement that should drop into Capacitor banks number.Send the instruction dropping into M group capacitor, cause corresponding voltage variety operation of power networks state will from (Q ⁽⁰⁾, U ⁽⁰⁾) become (Q ⁽¹⁾, U ⁽¹⁾), wherein $\left\{\begin{array}{c}{Q}^{\left(1\right)}=Q^{\left(0\right)}-M*{\mathrm{\&Delta;Q}}_q\\ U^{\left(1\right)}=U^{\left(0\right)}+\mathrm{\&Delta;U}\end{array}\right.$

(ii) if M>F _in, then F can only be dropped into _ingroup capacitor, correspondingly causes voltage variety to be operation of power networks state will from (Q ⁽⁰⁾, U ⁽⁰⁾) become (Q ⁽¹⁾, U ⁽¹⁾), wherein $\left\{\begin{array}{c}{Q}^{\left(1\right)}=Q^{\left(0\right)}-F_{\mathrm{in}}*{\mathrm{\&Delta;Q}}_q\\ U^{\left(1\right)}=U^{\left(0\right)}+\mathrm{\&Delta;U}\end{array}\right.$

(13) 13rd district: its provincial characteristics $\left\{\begin{array}{c}Q\&le;Q_O-{\mathrm{\&Delta;Q}}_q\\ U\&le;U_O-{\mathrm{\&Delta;U}}_u\end{array}\right.$

First judge whether the tap joint position k of on-load tap-changing transformer 2 is in lower limit k _minand whether action frequency N reaches maximum permission action frequency N _max.

If 1. k=k _minand N=N _maxin have an establishment at least, then the tap of on-load tap-changing transformer 2 cannot carry out gear shift action again, and dynamic electric voltage recovery device 5 direct action now should be allowed to produce voltage compensation quantity U _dVR=U _o-U ⁽⁰⁾, operation of power networks state will from (Q ⁽⁰⁾, U ⁽⁰⁾) become (Q ⁽¹⁾, U ⁽¹⁾), wherein $\left\{\begin{array}{c}{Q}^{\left(1\right)}=Q^{\left(0\right)}\\ U^{\left(1\right)}=U_O\end{array}\right.$

If 2. k ≠ k _minand N ≠ N _max, then make the tap downshift boosting of on-load tap-changing transformer 2, thus cause voltage variety to be Δ U _u=(Δ k/k) U ⁽⁰⁾, cause corresponding idle work variable quantity to be operation of power networks state will from (Q ⁽⁰⁾, U ⁽⁰⁾) become (Q ⁽¹⁾, U ⁽¹⁾), wherein $\left\{\begin{array}{c}{Q}^{\left(1\right)}=Q^{\left(0\right)}+{\mathrm{\&Delta;Q}}_q\\ U^{\left(1\right)}=U^{\left(0\right)}+{\mathrm{\&Delta;U}}_u\end{array}\right.$

(14) 14th district: its provincial characteristics $\left\{\begin{array}{c}{Q}_O-{\mathrm{\&Delta;Q}}_q<Q\&le;Q_O\\ U\&le;U_O-{\mathrm{\&Delta;U}}_u\end{array}\right.$

First judge whether the tap joint position k of on-load tap-changing transformer 2 is in lower limit k _minand whether action frequency N reaches maximum permission action frequency N _max.

If 1. k=k _minand N=N _maxin have an establishment at least, then illustrate that the tap of on-load tap-changing transformer 2 cannot carry out downshift boosting again, now should allow dynamic electric voltage recovery device 5 direct action generation voltage compensation quantity U _dVR=U _o-U ⁽⁰⁾, operation of power networks state will from (Q ⁽⁰⁾, U ⁽⁰⁾) become (Q ⁽¹⁾, U ⁽¹⁾), wherein $\left\{\begin{array}{c}{Q}^{\left(1\right)}=Q^{\left(0\right)}\\ U^{\left(1\right)}=U_O\end{array}\right.$

If 2. k ≠ k _minand N ≠ N _max, then make the tap downshift boosting of on-load tap-changing transformer 2, thus cause voltage variety to be Δ U _u=(Δ k/k) U ⁽⁰⁾, cause corresponding idle work variable quantity to be operation of power networks state will from (Q ⁽⁰⁾, U ⁽⁰⁾) become (Q ⁽¹⁾, U ⁽¹⁾), wherein $\left\{\begin{array}{c}{Q}^{\left(1\right)}=Q^{\left(0\right)}+{\mathrm{\&Delta;Q}}_q\\ U^{\left(1\right)}=U^{\left(0\right)}+{\mathrm{\&Delta;U}}_u\end{array}\right.$

(15) 15th district: its provincial characteristics $\left\{\begin{array}{c}{Q}_O<Q<Q_O+{\mathrm{\&Delta;Q}}_q\\ U\&le;U_O-{\mathrm{\&Delta;U}}_u\end{array}\right.$

First Q is judged ⁽⁰⁾-Q _o>Q _εset up no.

If 1. Q ⁽⁰⁾-Q _o>Q _ε, then idle controlling unit is entered.Allow the action of silent oscillation dynamic reactive generator 4 send perception idle, its value is Q _sVG=Q ⁽⁰⁾-Q _o, cause corresponding voltage variety operation of power networks state will from (Q ⁽⁰⁾, U ⁽⁰⁾) become (Q ⁽¹⁾, U ⁽¹⁾), wherein $\left\{\begin{array}{c}{Q}^{\left(1\right)}=Q_O\\ U^{\left(1\right)}=U^{\left(0\right)}+\mathrm{\&Delta;U}\end{array}\right.$

If 2. Q ⁽⁰⁾-Q _o≤ Q _ε, then voltage control link is entered.First, judge whether the tap joint position k of on-load tap-changing transformer 2 is in lower limit k _minand whether action frequency N reaches maximum permission action frequency N _max.

(i) if k=k _minand N=N _maxin have an establishment at least, then illustrate that the tap of on-load tap-changing transformer 2 cannot carry out downshift boosting again, now should allow dynamic electric voltage recovery device 5 direct action generation voltage compensation quantity U _dVR=U _o-U ⁽⁰⁾, operation of power networks state will from (Q ⁽⁰⁾, U ⁽⁰⁾) become (Q ⁽¹⁾, U ⁽¹⁾), wherein $\left\{\begin{array}{c}{Q}^{\left(1\right)}=Q_O\\ U^{\left(1\right)}=U_O\end{array}\right.$

(ii) if k ≠ k _minand N ≠ N _max, then make the tap downshift boosting of on-load tap-changing transformer 2, thus cause voltage variety to be Δ U _u=(Δ k/k) U ⁽⁰⁾, cause corresponding idle work variable quantity to be operation of power networks state will from (Q ⁽⁰⁾, U ⁽⁰⁾) become (Q ⁽¹⁾, U ⁽¹⁾), wherein $\left\{\begin{array}{c}{Q}^{\left(1\right)}=Q^{\left(0\right)}+{\mathrm{\&Delta;Q}}_q\\ U^{\left(1\right)}=U^{\left(0\right)}+{\mathrm{\&Delta;U}}_u\end{array}\right.$

(16) 16th district: its provincial characteristics $\left\{\begin{array}{c}Q\&GreaterEqual;Q_O+{\mathrm{\&Delta;Q}}_q\\ U\&le;U_O-{\mathrm{\&Delta;U}}_u\end{array}\right.$

First judge that capacitor can drop into group number F _inwhether be 0.

If 1. F _in=0, then illustrate that capacitorless can be thrown.Need to make silent oscillation dynamic reactive generator 4 send lagging reactive power, its value is Q _sVG=Q ⁽⁰⁾-Q _o, cause corresponding voltage variety operation of power networks state will from (Q ⁽⁰⁾, U ⁽⁰⁾) become (Q ⁽¹⁾, U ⁽¹⁾), wherein $\left\{\begin{array}{c}{Q}^{\left(1\right)}=Q_O\\ U^{\left(1\right)}=U^{\left(0\right)}+\mathrm{\&Delta;U}\end{array}\right.$

If 2. F _in≠ 0, then can drop into Capacitor banks 3.By | Q _o-Q ⁽⁰⁾|/Δ Q _q=M.m known needs drops into M group capacitor.

If (i) M≤F _in, then can drop into Capacitor banks and count up to and all can enough meet the requirement that should drop into Capacitor banks number.Send the instruction dropping into M group capacitor, cause corresponding voltage variety operation of power networks state will from (Q ⁽⁰⁾, U ⁽⁰⁾) become (Q ⁽¹⁾, U ⁽¹⁾), wherein $\left\{\begin{array}{c}{Q}^{\left(1\right)}=Q^{\left(0\right)}-M*{\mathrm{\&Delta;Q}}_q\\ U^{\left(1\right)}=U^{\left(0\right)}+\mathrm{\&Delta;U}\end{array}\right.$

(ii) if M>F _in, then F can only be dropped into _ingroup capacitor, correspondingly causes voltage variety to be operation of power networks state will from (Q ⁽⁰⁾, U ⁽⁰⁾) become (Q ⁽¹⁾, U ⁽¹⁾), wherein $\left\{\begin{array}{c}{Q}^{\left(1\right)}=Q^{\left(0\right)}-F_{\mathrm{in}}*{\mathrm{\&Delta;Q}}_q\\ U^{\left(1\right)}=U^{\left(0\right)}+\mathrm{\&Delta;U}\end{array}\right.$

The emulation experiment model of the wind-electricity integration electricity generation system containing DVQC has as shown in Figure 1 been built under MATLAB/SIMULINK simulated environment.It is that the wind energy turbine set of 50MW is through 110/35kV boosting on-load tap-changing transformer access electrical network that this simulation model simulates capacity, wind energy turbine set unit is collected to wind energy turbine set 110kV booster stations with 35kV voltage, go out a 110kV circuit (LGJ-240) to access on the 110kV bus of certain 220kV transformer station, line length is about 18km.Wherein, the two volume step-up transformer of three-phase oil immersion air-cooled copper winding on-load voltage regulation selected by main transformer, and its model specification is: SFPZ-50000/110121 ± 8*1.25%/35kV; This wind energy turbine set primary substation low-pressure side bus is in parallel, and 8 pool-sizes are the capacitor of 2000kVar; Silent oscillation dynamic reactive generator SVG capacity is 10Mvar.This analogue system has carried out emulation experiment under the Wind speed up operating mode of simulation and the actual measurement wind speed operating mode of certain wind energy turbine set domestic.Simulation result as represented in figures 4 to 11, wherein Fig. 4 ~ 7 are the wind speed of wind-powered electricity generation grid-connected system under Wind speed up operating mode, meritorious, idle and change in voltage correlation curve before and after DVQC regulates, and Fig. 8 ~ 11 be the wind speed of wind-powered electricity generation grid-connected system under actual measurement wind speed operating mode, meritorious, the idle and change in voltage correlation curve that regulates front and back through DVQC.

From Fig. 4 ~ 11, the adjustment of the dynamic electric voltage powerless control system DVQC by the idle composite coordination control method of dynamic electric voltage based on " 16 district figure " can be found out in Wind speed up operating mode and a kind of simulation result of surveying under wind speed operating mode by wind-electricity integration electricity generation system simulation model, the voltage power-less fluctuation that wind speed drastic change and fluctuations in wind speed cause obtains and effectively suppresses, significantly improve the voltage power-less running status of electrical network, compensation effect is more accurate, greatly improves security and stability and the economy of operation of power networks.

Claims (1)

1. A network voltage and reactive power composite coordinated control method for new energy generation, characterized in that, the method may further comprise the steps: Step 1: The voltage and reactive power composite coordination controller (1) is initialized, and receives the collected information after initialization; Step 2: Voltage and reactive power composite coordination controller (1) judges that the voltage and reactive power operating state of the current system is in the sixteenth zone according to the bus voltage U ⁽⁰⁾ on the low voltage side of the substation and the reactive power Q ⁽⁰⁾ injected into the high voltage side The area in the graph partition; Step 3: Voltage and reactive power composite coordination controller (1) According to the area where the current system voltage and reactive power operating state is located, according to the collected information and the control strategy corresponding to the area in the control strategy of the 16-area map, the on-load dispatcher Transformer (2), capacitor bank (3), static dynamic var generator (4) and dynamic voltage restorer (5) send instructions; Step 4: On-load tap changer (2), capacitor bank (3), static dynamic var generator (4) and dynamic voltage restorer (5) receive the voltage and reactive power composite coordination controller (1) sent After the instruction, carry out the corresponding action to realize the dynamic compound coordination control of voltage and reactive power; In the described step 1, the information includes the busbar voltage U ⁽⁰⁾ at the low-voltage side of the substation; the reactive power Q ⁽⁰⁾ injected at the high-voltage side; the number of times N of tap taps of the on-load tap changer (2) that day; The group number F _in , the group number F _out of the removable capacitor bank; the current gear position k of the tap of the on-load tap changer transformer (2); The specific partitioning method of the sixteen district map in the step 2 is as follows: Region I: Regional Characteristics Zone II: Regional Characteristics Zone III: Regional Characteristics Region Four: Regional Characteristics Zone V: Regional Characteristics Region VI: Regional Characteristics Region VII: Regional Characteristics Region Eight: Regional Characteristics District Nine: Regional Characteristics District Ten: Regional Characteristics District XI: Regional Characteristics District XII: Regional Characteristics District Thirteen: Regional Characteristics District Fourteen: Regional Characteristics District XV: Regional Characteristics Sixteenth District: Regional Characteristics Among them, point O is the optimal operating state of the power grid, U _O is the voltage in the optimal operating state, Q _O is the reactive power in the optimal operating state, Q is the reactive power in the current operating state of the system, and U is the current state of the system. The voltage in the running state, △Q _q is the reactive power change caused by switching a group of capacitors, △U _u is the voltage change caused by adjusting the tap change of the on-load tap changer (2); In the step 2, the control strategy of the sixteen district map is: One district strategy: (1) If F _out ≠ 0, calculate Mm＝|Q ⁽⁰⁾ -Q _O |/ΔQ _q ; (i) If M≤F _out , the voltage and reactive power composite coordination controller (1) issue an instruction to cut off M groups of capacitors ; (ii) If M>F _out , the voltage and reactive power composite coordination controller (1) issues an instruction to cut off the F _out group capacitor; (2) If F _out = 0, the voltage reactive composite coordination controller (1) issues an instruction to make the static dynamic var generator (4) issue a reactive compensation amount Q _SVG = Q ⁽⁰⁾ -Q _O ; Zone Two Strategy: (1) If Q _O -Q ⁽⁰⁾ >Q _ε , Q _ε is the allowable reactive power adjustment deviation in actual operating conditions, enters the reactive power control link, and the voltage reactive power composite coordination controller (1) issues instructions Make static type dynamic var generator (4) send out reactive power compensation Q _SVG =Q ⁽⁰⁾ -Q _O ; (2) If Q _O -Q ⁽⁰⁾ ≤ Q _ε , enter the voltage control link, (i) if at least one of k=k _max and N=N _max is established, N _max is the maximum number of daily actions of the tap, The voltage-reactive compound coordination controller (1) issues an instruction to make the dynamic voltage restorer (5) issue voltage compensation U _DVR =U _O -U ⁽⁰⁾ ; (ii) if k<k _max and N<N _max , the voltage has no The power compound coordination controller (1) issues an instruction to make the tap of the on-load tap changer (2) rise to a gear; Three-zone strategy: (1) If at least one of k=k _max and N=N _max is established, the voltage reactive power composite coordination controller (1) issues an instruction to make the dynamic voltage restorer (5) generate voltage compensation U _DVR =U _O -U ⁽⁰⁾ ; (2) If k<k _max and N<N _max , the voltage-reactive composite coordinating controller (1) issues an instruction to upgrade the tap of the on-load tap changer (2) to one gear; Four-zone strategy: (1) If at least one of k=k _max and N=N _max is established, the voltage reactive power composite coordination controller (1) issues an instruction to make the dynamic voltage restorer (5) generate voltage compensation U _DVR =U _O -U ⁽⁰⁾ ; (2) If k<k _max and N<N _max , the voltage-reactive composite coordinating controller (1) issues an instruction to upgrade the tap of the on-load tap changer (2) to one gear; Five-zone strategy: (1) If F _out ≠ 0, Mm＝|Q ⁽⁰⁾ -Q _O |/ΔQ _q , (i) If M≤F _out , the voltage and reactive composite coordination controller (1) issues an instruction to remove M groups of capacitors; (ii) If M>F _out , the voltage reactive power composite coordination controller (1) issues an instruction to cut off the F _out group capacitor; (2) If F _out = 0, the voltage reactive composite coordination controller (1) issues an instruction to make the static dynamic var generator (4) issue a reactive compensation amount Q _SVG = Q ⁽⁰⁾ -Q _O ; Six-zone strategy: (1) If Q _O -Q ⁽⁰⁾ >Q _ε , enter the reactive power control link, and the voltage reactive power composite coordination controller (1) issues an instruction to make the static dynamic var generator (4) issue a reactive power compensation amount Q _SVG = Q ⁽⁰⁾ - Q _O ; (2) If Q _O -Q ⁽⁰⁾ ≤ Q _ε , enter the voltage control link, and the voltage reactive power composite coordination controller (1) issues an instruction to make the dynamic voltage restorer (5) generate voltage compensation U _DVR = U _O - U ⁽⁰⁾ ; Seven District Strategy: The voltage and reactive composite coordination controller (1) issues an instruction to make the dynamic voltage restorer (5) generate a voltage compensation amount U _DVR = U _O - U ⁽⁰⁾ ; Eight district strategy: The voltage and reactive composite coordination controller (1) issues an instruction to make the dynamic voltage restorer (5) generate a voltage compensation amount U _DVR = U _O - U ⁽⁰⁾ ; Nine District Strategy: The voltage and reactive composite coordination controller (1) issues an instruction to make the dynamic voltage restorer (5) generate a voltage compensation amount U _DVR = U _O - U ⁽⁰⁾ ; Ten District Strategy: The voltage and reactive composite coordination controller (1) issues an instruction to make the dynamic voltage restorer (5) generate a voltage compensation amount U _DVR = U _O - U ⁽⁰⁾ ; Eleven District Strategy: (1) If Q ⁽⁰⁾ -Q _O >Q _ε , enter the reactive power control link, and the voltage reactive power composite coordination controller (1) issues an instruction to make the static dynamic var generator (4) issue a reactive power compensation amount Q _SVG = Q ⁽⁰⁾ - Q _O ; (2) If Q ⁽⁰⁾ -Q _O ≤ Q _ε , enter the voltage control link; the voltage and reactive power composite coordination controller (1) issues an instruction to make the dynamic voltage restorer (5) generate voltage compensation U _DVR = U _O - U ⁽⁰⁾ ; Twelve District Strategy: (1) If F _in = 0, the voltage reactive composite coordination controller (1) issues an instruction to make the static dynamic var generator (4) issue a reactive compensation amount Q _SVG = Q ⁽⁰⁾ -Q _O ; (2) If F _in ≠0, calculate Mm=|Q ⁽⁰⁾ -Q _O |/ΔQ _q ; (i) If M≤F _in , the voltage and reactive power composite coordination controller (1) issues an instruction to input M groups of capacitors; (ii) If M>F _in , the voltage and reactive power composite coordination controller (1) issues an instruction to input the F _in group capacitor; Thirteen district strategy: (1) If at least one of k=k _min and N=N _max is established, the voltage reactive power composite coordination controller (1) issues an instruction to make the dynamic voltage restorer (5) generate voltage compensation U _DVR =U _O -U ⁽⁰⁾ ; (2) If k≠k _min and N≠N _max , the voltage-reactive compound coordinating controller (1) issues an instruction to lower the tap of the on-load tap changer (2) by one gear; Fourteen District Strategy: (1) If at least one of k=k _min and N=N _max is established, the voltage reactive power composite coordination controller (1) issues an instruction to make the dynamic voltage restorer (5) generate voltage compensation U _DVR =U _O -U ⁽⁰⁾ ; (2) If k≠k _min and N≠N _max , the voltage-reactive compound coordinating controller (1) issues an instruction to lower the tap of the on-load tap changer (2) by one gear; Fifteen district strategy: (1) If Q ⁽⁰⁾ -Q _O >Q _ε , enter the reactive power control link, and the voltage reactive power composite coordination controller (1) issues an instruction to make the static dynamic var generator (4) issue a reactive power compensation amount Q _SVG = Q ⁽⁰⁾ - Q _O ; (2) If Q ⁽⁰⁾ -Q _O ≤ Q _ε , enter the voltage control link, (i) if at least one of k=k _min and N=N _max is established, the voltage reactive power composite coordination controller (1) sends The instruction makes the dynamic voltage restorer (5) generate the voltage compensation U _DVR =U _O -U ⁽⁰⁾ ; (ii) if k≠k _min and N≠N _max , the voltage reactive composite coordination controller (1) issues an instruction Lower the tap of the on-load tap changer (2) by one gear; Sixteen district strategy: (1) If F _in = 0, the voltage reactive composite coordination controller (1) issues an instruction to make the static dynamic var generator (4) issue a reactive compensation amount Q _SVG = Q ⁽⁰⁾ -Q _O ; (2) If F _in ≠ 0, calculate Mm＝|Q ⁽⁰⁾ -Q _O |/ΔQ _q ; (i) If M≤F _in , the voltage and reactive composite coordination controller (1) issue an instruction to input M groups of capacitors ; (ii) If M>F _in , the voltage and reactive composite coordination controller (1) issues an instruction to put into the F _in group capacitor; Wherein, the total group number of the capacitor bank (3) is F _in +F _out ; Mm is the value of |Q ⁽⁰⁾ -Q _O |/ΔQ _q , wherein M represents |Q ⁽⁰⁾ -Q _O |/ΔQ _q The integer part of , m represents the fractional part of |Q ⁽⁰⁾ -Q _O |/ΔQ _q ; the upper limit position of the tap of the on-load tap changer (2) is k _max , and the lower limit position is k _min .