CN101917060A - Automatic power generation control method - Google Patents

Abstract

The invention relates to an automatic power generation control method, which is implemented by an automatic control power generation system, namely an AGC system. The method comprises the following steps: (1) acquiring and computing area control error (ACE) of a power grid by using an SCADA system; (2) filtering the value of ACE; (3) setting an ACE regulation dead zone; (4) computing a proportional regulating variable; (5) computing a load ramp auxiliary regulating variable Pset2; (6) computing a sudden force application regulating variable Pset3; (7) computing an error integral regulating variable Pset4; and (8) distributing the output power of the machine set by using a unit value. The method has the advantages of quickly, efficiently and smoothly regulating the active power balance of the power grid, and greatly improving the economy and safety of the operation of the power grid.

Description

A kind of automatic power generation control method

Technical field

The present invention relates to a kind of automatic power generation control method, belong to automatic generation control under A1, the A2 control criterion.

Background technology

Automatic generation control is called for short AGC (Automatic Generation Control), it is the important component part of EMS (EMS), controlled target by grid dispatching center sends to concerned power generation factory or unit with instruction, by the automatic control and adjustment device of power plant or unit, realize automatic control to generator power.

As the part of North China-Central China interconnected network, southern power grid main employing in the past in Hebei is manually assigned instruction adjusting power plant and is exerted oneself.The data that grid dispatching center collects by each automatization terminal are carried out the clean exchange power error of interconnection between frequency error and net comprehensively, and the Region control error (Area Control Error) of formation Hebei southern power grid is designated hereinafter simply as ACE.Routine dispatching person assigns unit output instruction by phone to the power plant, to the distribution of exerting oneself of gaining merit of each generating set, makes ACE level off to 0.

Hebei southern power grid ACE appraisal standards are undertaken by the A1 of North America Reliability Committee (NERC), A2 standard, are made up of 2 parts: A ₁, in the 15min ACE at least zero passage once, this is in order to guarantee that ACE is within controlled range; A ₂, i.e. the mean value of the ACE of 15min should be less than given limit value, so that control is offset from the electric weight of program trading value.

Along with the scale of China's electric power system is increasing, particularly extra-high voltage grid north and south interconnected after, the amplitude that Power Exchange and system loading change between net strengthens, and traditional manually assign instruction and regulates power plant and exert oneself and be difficult to adapt to electric network active and regulate requirement.The fluctuation of ACE will certainly cause harmful effect to electric power netting safe running.Therefore generator power is controlled automatically, fast, efficiently, smoothly adjustment electric network active power-balance becomes the task of top priority.

Domestic AGC correlation technique is just discussed control model and examination strategy mostly at present, and paper is to be based upon on the basis of simulation example mostly, and relevant detailed, concrete calculating and control method in actual electric network operation control rarely have argumentation.

Summary of the invention

Technical problem to be solved by this invention provide can fast, efficiently, smoothly adjustment electric network active power-balance a kind of automatic power generation control method.

The technical solution adopted for the present invention to solve the technical problems is as follows:

It is that the AGC system finishes that the present invention adopts automatic control electricity generation system, it is characterized in that concrete steps are as follows:

(1) utilize SCADA system acquisition and the Region control error ACE that calculates electrical network:

ACE＝ΔP+KΔF (1)

In the formula, ACE is the Region control error, and unit is Mw; Δ P is current interconnection power deviation, and unit is Mw; K is the electric network active _ frequecy characteristic value of somewhere electrical network, and unit is Mw/Hz; Δ F is current exemplary frequency deviation values, and unit is Hz;

(2) described ACE value is carried out filtering:

Filtering method is as follows: adopt 5 methods of average, promptly with 5 nearest ACE values, average;

(3) ACE is set and regulates the dead band:

ACE regulates the dead band: | A _f|＞55

A _fBe the ACE value;

(4) calculate ratio regulated quantity P _Set1:

Work as A _fAfter breaking through described adjusting dead band, ratio regulated quantity P of described AGC system's generation _Set1

P _set1＝(|A _f|-55)*1.05*(A _f/|A _f|)，|A _f|＞55 (2)

P in the formula _Set1Be the ratio regulated quantity, 1.05 is the proportionality coefficient relevant with the unit individual features;

(5) calculated load climbing auxiliary adjustment amount P _Set2

Work as A _fAfter breaking through described adjusting dead band, and somewhere electrical network SCADA system per 5 seconds gathers load P and calculates once, and described AGC system calculated a slope in per 15 seconds to load P, as load slope A _xDuring greater than 6MW/min, load climbing assistant starting produces load climbing auxiliary adjustment amount P _Set2

$A_x=\frac{\∂P}{\∂t}=(P_3-P_1)*4---\left(3\right)$

In the formula, A _xBe the load slope, unit is Mw/min; P ₃Load when being 15 seconds, P ₁Load when being 0 second, P ₁, P ₃Unit be Mw;

P _set2＝(A _x-6)*7.5，A _x＞6 (4)

P in the formula _Set2Be load climbing auxiliary adjustment amount, 6 are load slope dead band value, and 7.5 is coefficient;

(6) calculate the afterburning regulated quantity P of sudden change _Set3

Work as A _fAfter breaking through described adjusting dead band, and unusual when the electrical network generation, and ACE undergos mutation, to each A _fBy its sudden change amount of described AGC system-computed A _m:

A _m＝(A _f1-A _f2)*60/5＝(A _f1-A _f2)*12 (5)

A in the formula _mBe the sudden change amount of ACE value, unit is Mw; A _F1, A _F2Be respectively the filter value of the ACE value of former and later two adjacent moment, work as A then _mDuring greater than 3Mw, produce the afterburning regulated quantity P of sudden change _Set3:

P _set3＝6*(A _m-3) (6)

In the formula: P _Set3Be the afterburning regulated quantity of suddenling change, 3 are sudden change amount dead band, and 6 is coefficient;

(7) error of calculation integration regulated quantity P _Set4

Work as A _fAfter breaking through described adjusting dead band, and in a 15min assessment period to A ₁Continue to depart from 0 and produce error value product component A _j, make A ₂Level off to zero, work as A _jAfter error value product component dead band value, produce error intergal regulated quantity P _Set4

$A_j=\underset{0}{\overset{15\min }{\∫}}{A}_1\∂t=\underset{1}{\overset{180}{\mathrm{\Σ}}}{A}_1---\left(7\right)$

P _set4＝6.29*(A _j-23) (8)

In the formula, P _Set4Be error intergal regulated quantity, A _jBe the error value product component, unit is Mw; 6.29 be coefficient, 23 is the dead band value of error value product component;

Described P _Set1-P _Set4Unit be Mw;

(8) adopt perunit value to the unit distribution of exerting oneself

After above-mentioned 4 regulated quantitys produced, algebraic addition obtained a final comprehensive adjustment amount P _Set, this comprehensive adjustment amount is distributed in each control unit;

Dividing hour apportion designs such as timing employing, promptly is fiducial value with the adjustable range, is side-play amount with the difference of unit output and adjusting lower limit, i.e. perunit value, perunit value=(unit output-adjusting lower limit)/(unit capacity-adjusting lower limit); Work as P _SetWhen promptly rising from power, assign instruction, distribute successively according to 4% of unit capacity by perunit value order from low to high for timing; When all units all distribute, then start anew once more the residual accommodation amount to be distributed, until having divided; Work as P _SetFall when negative when exerting oneself and assign instruction by perunit value order from high to low, distribution method is the same.

The invention has the beneficial effects as follows can fast, efficiently, smoothly adjustment electric network active power-balance, has improved the economy and the fail safe of operation of power networks greatly.

Description of drawings

Fig. 1 is AGC system works flow process figure (control model).

Fig. 2 is the AGC system principle diagram.

Embodiment

Embodiment (referring to Fig. 1,2):

The concrete steps of present embodiment are as follows:

1.ACE collection, calculating and filtering

In the electrical network each moves unit, comprises each equipment of power plant and transformer station, and the terminal (SCADA system) of responsible image data is all arranged, and these terminals are transferred to province with the data that collect by fiber optic network and transfer the automation machine room.Economize then to transfer above-mentioned data are changed and calculated, obtain each data of operation of power networks control, ACE is one of them.The TBC control mode is adopted in electrical network each regional power grid adjustment in North China.

ACE＝ΔP+KΔF (1)

Wherein Δ P is current interconnection power deviation, and K is the electric network active-frequency characteristic value of Hebei southern power grid, and Δ F is current exemplary frequency deviation values.

Too frequent for fear of AGC control, at first the ACE value is carried out filtering, filtering method is: 5 methods of average, with 5 nearest ACE values, average.

Because after the power plant unit received that province transfers the AGC instruction, the unit adjustment had hysteresis effect (the Hebei Southern network source is thermoelectricity substantially, and the relative water power of fired power generating unit regulations speed is slower).Relatively relax through ACE curvilinear motion after the filtering, trend is also more fixing, the regulated quantity of AGC instruction also can effectively minimizing generator.

2. the dead band is set

Because interconnection and load variations are frequent between net, the ACE value presents the trend of quick concussion.For fear of the frequent and excessive adjustment of AGC, the ACE value is provided with the adjusting dead band.It is 55 that Hebei Southern net ACE regulates the dead band, i.e. A _fAfter value departed from 0 55, AGC regulated program start, and unit is sent the regulating command of exerting oneself, so that the ACE value is returned to 0.After deviation value is lower than 55, send instructions under stopping.

3. ratio regulated quantity P _Set1Generation

For A _fValue behind the breakthrough dead band, the AGC system produces a ratio regulated quantity P to it _Set1:

P _set1＝(|A _f|-55)*1.05*(A _f/|A _f|)，|A _f|＞55 (2)

Wherein 1.05 is the proportionality coefficient relevant with the unit individual features.

4. the climbing auxiliary adjustment of loading amount P _Set2Generation

Because Hebei Southern net load peak-valley difference is very big, particularly some period loads present zooming trend.To this, work as A _fAfter breaking through described adjusting dead band, and after the rate of change of loading was greater than certain value, the AGC system produced load climbing auxiliary adjustment amount P _Set2Calculating is gathered once to load P per 5 seconds by Hebei Southern net SCADA system, and the AGC system calculated a slope in per 15 seconds to P.As load slope A _xDuring greater than 6MW/min, load climbing assistant starting produces load climbing auxiliary adjustment amount P _Set2

$A_x=\frac{\∂P}{\∂t}=(P_3-P_1)*4,---\left(3\right)$

P wherein ₃Load when being 15 seconds, P ₁Load when being 0 second.

P _set2＝(A _x-6)*7.5，A _x＞6 (4)

Wherein 6 are load slope dead band value, and 7.5 is coefficient.

The afterburning regulated quantity P 5.ACE suddenly change _Set3Generation

Some are unusual when electrical network takes place, and during as big capacity unit breaking or pumped storage unit starting, this moment, load big variation can not take place, but the ACE value can undergo mutation, and numerical value is far longer than dead band value, as 600MW unit breaking, A ₁Moment can reach-500Mw.Need this moment a large amount of units to adjust rapidly and exert oneself, avoid A ₁Cross low or too high frequency anomaly that causes and even power grid accident.Therefore, to each A _fCalculate its sudden change amount A _m:

A _m＝(A _f1-A _f2)*60/5＝(A _f1-A _f2)*12 (5)

A wherein _F1, A _F2Be respectively the filter value of former and later two adjacent moment, work as A then _mDuring greater than 3MW, produce the afterburning regulated quantity P of sudden change _Set3:

P _set3＝6*(A _m-3) (6)

Wherein 6 is coefficient, and 3 are sudden change amount dead band.

6. ACE being carried out error intergal regulates

Above-mentioned each regulated quantity can meet A substantially ₁The examination requirement.But if A ₁Depart from for a long time near 50-55, when the sudden change of assessment period internal loading of last a few minutes, ACE continues greater than dead band value, then A ₂Be difficult to reach the examination requirement.To this, (15min) is to A in an assessment period ₁Continue to depart from 0 and produce error intergal signal A _j, make A ₂Level off to zero.Work as A _jAfter error value product component dead band value, produce error intergal regulated quantity P _Set4

$A_j=\underset{0}{\overset{15\min }{\∫}}{A}_1\∂t=\underset{1}{\overset{180}{\mathrm{\Σ}}}{A}_1---\left(7\right)$

P _set4＝6.29*(A _j-23) (8)

Wherein 6.29 is coefficient, and 23 is error value product component dead band value.

7. adopt perunit value to the unit distribution of exerting oneself

After above-mentioned 4 regulated quantitys produced, algebraic addition obtained a final comprehensive adjustment amount P _Set, this regulated quantity is distributed in each control unit.

Dividing hour apportion designs such as timing employing, promptly is fiducial value with the adjustable range, is side-play amount (perunit value) with unit output with the difference of regulating lower limit.Perunit value=(unit output-adjusting lower limit)/(unit capacity-adjusting lower limit).As the deep blue east #2 of power plant generator, capacity 600MW, the 400MW that exerts oneself this moment, then perunit value is (400-300)/(600-300)=0.333.Emersion power (P _SetFor just) time, assign instruction by perunit value order from low to high, distribute successively according to 4% of unit capacity.If all units all distribute, then start anew to remain once more the conciliation amount and distribute, until having divided.(P when exerting oneself falls _SetFor negative) assign instruction by perunit value order from high to low, distribution method is the same.

AGC system works flow process as shown in Figure 1, the diagram workflow be a cycle period with 15 seconds.The SCADA system is imported the data that collect into after the AGC system, through filtering, produces filtered ACE curve.If do not exceed the dead band, then the AGC system program is not regulated; If exceed the dead band, then the AGC system begins to calculate sudden change amount, integration amount and load slope.Each regulated quantity addition by ratio is regulated, sudden change is afterburning, integration amount is regulated, the climbing power-assisted produces obtains a total regulated quantity.Then regulated quantity is calculated and spread out of to each controller batch total.

Fig. 2 is the AGC system principle diagram, explained somewhere electrical network AGC system the control unit sent the process that mains frequency is controlled in regulating command, for example, the AGC regulated quantity P that first generating set will receive from provincial control centre AGC system _Set1With the self generating P that exerts oneself ₁₁In first comparator, obtain the current desired value P that exerts oneself after the addition ₁₂, exert oneself by the first gen-set control system regulator generator group then.

Claims (1)

1. automatic power generation control method, its adopts automatically that the control electricity generation system is that the AGC system finishes, and it is characterized in that concrete steps are as follows:

(1) utilize SCADA system acquisition and the Region control error ACE that calculates electrical network:

ACE＝ΔP+KΔF (1)

In the formula, ACE is the Region control error, and unit is Mw; Δ P is current interconnection power deviation, and unit is Mw; K is the electric network active _ frequecy characteristic value of somewhere electrical network, and unit is Mw/Hz; Δ F is current exemplary frequency deviation values, and unit is Hz;

(2) described ACE value is carried out filtering:

Filtering method is as follows: adopt 5 methods of average, promptly with 5 nearest ACE values, average;

(3) ACE is set and regulates the dead band:

ACE regulates the dead band: | A _f|＞55

A _fBe the ACE value;

(4) calculate ratio regulated quantity P _Set1:

Work as A _fAfter breaking through described adjusting dead band, ratio regulated quantity P of described AGC system's generation _Set1

P _set1＝(|A _f|-55)*1.05*(A _f/|A _f|)，|A _f|＞55 (2)

P in the formula _Set1Be the ratio regulated quantity, 1.05 is the proportionality coefficient relevant with the unit individual features;

(5) calculated load climbing auxiliary adjustment amount P _Set2

Work as A _fAfter breaking through described adjusting dead band, and somewhere electrical network SCADA system per 5 seconds gathers load P and calculates once, and described AGC system calculated a slope in per 15 seconds to load P, as load slope A _xDuring greater than 6MW/min, load climbing assistant starting produces load climbing auxiliary adjustment amount P _Set2

$A_x=\frac{\∂P}{\∂t}=(P_3-P_1)*4---\left(3\right)$

In the formula, A _xBe the load slope, unit is Mw/min; P ₃Load when being 15 seconds, P ₁Load when being 0 second, P ₁, P ₃Unit be Mw;

P _set2＝(A _x-6)*7.5，A _x＞6 (4)

P in the formula _Set2Be load climbing auxiliary adjustment amount, 6 are load slope dead band value, and 7.5 is coefficient;

(6) calculate the afterburning regulated quantity P of sudden change _Set3

After Af breaks through described adjusting dead band, and unusual when the electrical network generation, and ACE undergos mutation, to each A _fBy its sudden change amount of described AGC system-computed A _m:

A _m＝(A _f1-A _f2)*60/5＝(A _f1-A _f2)*12 (5)

A in the formula _mBe the sudden change amount of ACE value, unit is Mw; A _F1, A _F2Be respectively the filter value of the ACE value of former and later two adjacent moment, work as A then _mDuring greater than 3Mw, produce the afterburning regulated quantity P of sudden change _Set3:

P _set3＝6*(A _m-3) (6)

In the formula: P _Set3Be the afterburning regulated quantity of suddenling change, 3 are sudden change amount dead band, and 6 is coefficient;

(7) error of calculation integration regulated quantity P _Set4

Work as A _fAfter breaking through described adjusting dead band, and in a 15min assessment period to A ₁Continue to depart from 0 and produce error value product component A _j, make A ₂Level off to zero, work as A _jAfter error value product component dead band value, produce error intergal regulated quantity P _Set4

$A_j=\underset{0}{\overset{15\min }{\∫}}{A}_1\∂t=\underset{1}{\overset{180}{\mathrm{\Σ}}}{A}_1---\left(7\right)$

P _set4＝6.29*(A _j-23) (8)

In the formula, P _Set4Be error intergal regulated quantity, A _jBe the error value product component, unit is Mw; 6.29 be coefficient, 23 is the dead band value of error value product component;

Described P _Set1-P _Set4Unit be Mw;

(8) adopt perunit value to the unit distribution of exerting oneself

After above-mentioned 4 regulated quantitys produced, algebraic addition obtained a final comprehensive adjustment amount P _Set, this comprehensive adjustment amount is distributed in each control unit;

Dividing hour apportion designs such as timing employing, promptly is fiducial value with the adjustable range, is side-play amount with the difference of unit output and adjusting lower limit, i.e. perunit value, perunit value=(unit output-adjusting lower limit)/(unit capacity-adjusting lower limit); Work as P _SetWhen promptly rising from power, assign instruction, distribute successively according to 4% of unit capacity by perunit value order from low to high for timing; When all units all distribute, then start anew once more the residual accommodation amount to be distributed, until having divided; Work as P _SetFall when negative when exerting oneself and assign instruction by perunit value order from high to low, distribution method is the same.

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