CN103023024A - Computing method for transmission grid active loss reduction by automatic voltage control - Google Patents

Abstract

The invention relates to a computing method for transmission grid active loss reduction by automatic voltage control and belongs to the technical field of automatic voltage control of power systems. The method comprises the steps of first reversely simulating control strategies of an automatic voltage control system on the basis of a current state of a transmission grid, performing load flow calculation, obtaining transmission grid active power loss in a simulated state, and comparing the transmission grid active power loss in the simulated state with the active power loss in the current actual state, and obtaining reduced values of the transmission grid active power loss through automatic voltage control in each turn; then, accumulating the reduced values of the transmission grid active power loss obtained by calculation in each turn, and performing integral in a time axis, and obtaining reduced values of transmission grid active electric quantity loss within continuous time periods. By adopting the method, values of the transmission grid active loss reduction caused by the automatic voltage control system can be calculated on line, benefits generated by the automatic voltage control system are analyzed accurately, and scientific bases are provided for operating maintenance workers to evaluate and improve running level of the system.

Description

A kind of computational methods that caused power transmission network active loss reduction by automatism voltage control

Technical field

The present invention relates to a kind of computational methods that caused power transmission network active loss reduction by automatism voltage control, belong to electric power system automatism voltage control technical field.

Background technology

Automatism voltage control (hereinafter to be referred as AVC, Automatic Voltage Control) system realizes the important means of power transmission network safety (raising voltage stability margin), economic (reduction via net loss), high-quality (raising rate of qualified voltage) operation.The AVC system architecture is on energy management system (EMS), can utilize the power transmission network real-time running data, go out best var-volt regulation scheme from the angle science decision of power transmission network global optimization, automatically be handed down to power plant, transformer station and dispatching of power netwoks mechanism of subordinate and carry out.Sun Hongbin, Zhang Baiming, Guo Qing have illustrated the architecture of large electrical network automatism voltage control in " based on the overall voltage optimization Control System Design of soft sectoring " (Automation of Electric Systems,, the 8th phase of the 27th volume, 16-20 page or leaf in 2003).

The main website of AVC system partly realizes based on software in Power System Control Centers, and its voltage control strategy to power transmission network mainly contains to each generator reactive control strategy of power plant and to reactive apparatus control strategy 2 classes of transformer station.Wherein to the idle control strategy of each generator of power plant, the major way that adopts at present is: after the AVC main station system of control centre calculates the idle regulated quantity of each unit of power plant by idle work optimization, send by the AVC substation system of data communication channel to power plant, after the AVC substation of power plant receives the generator reactive adjustment amount, running status according to each generator in the current power plant, adopt step-by-step system to adjust the reactive power that generator sends, until reach the adjustment amount that the AVC main website issues.Be switching instruction to reactive-load compensation equipment to the control strategy of transformer station, reactive apparatus mainly comprises capacitor and reactor, and when dropping into capacitor or excision reactor, busbar voltage raises; When excision capacitor or input reactor, busbar voltage reduces.The AVC main website issues and drops into or the instruction of excision reactive apparatus, and the Automatic monitoring systems transformer station in are according to the instruction of reception, finds the circuit breaker that reactive apparatus connects and closes or cut-off breaker, with input or the excision of finishing reactive apparatus.

Power network is being carried and is being distributed in the process of electric energy, because transmission facility exists resistance, when electric current flows through, will produce the active power loss of some, within the given period (day, the moon, season, year), the whole active energies that consume in each grid equipment are called Energy loss, generally comprise the active energy that active energy that line facility consumes and transformer equipment consume, and can be referred to as the active energy that branch road consumes.A major control target of AVC system is guaranteeing that voltage reduces active loss in qualified the largelyst exactly.After the AVC system drops into closed-loop control, can reduce the active loss of electrical network, thereby obtain the benefit of highly significant, and the numerical value that the power transmission network active loss that is caused by the AVC system is reduced calculating and analyzes, also is the important means of estimating AVC running quality and system level.

The account form of electric network active loss can be divided into statistics loss and theoretical loss two classes.The statistics loss is calculated according to the electric energy meter indicated number, depends on the data acquisition of electric energy meter meter, layouted and the constraint such as image data real-time by table meter, is difficult to use in and carries out online analysis.Theoretical loss is electric network composition parameter and the operational factor of basis, use the theory in the principles of electric and electronic engineering and the electricity, the voltage, electric current and the corresponding loss that comprise each transmission facility in the power transmission network model are calculated, the loss that calculates like this is referred to as theoretical loss, and the theoretical loss of whole power transmission network is the theoretical loss sum of the whole electric equipments that comprise in the computation model.Theoretical loss calculates and can carry out online, and its real-time is high, and the restriction that is not subjected to ammeter to layout and gather can be used for real-time Losses analysis and calculation.The meritorious trend value calculating of the equipment that calculates according to electric network swim Δ P has been described among Li Xuyang, the Xing Bozai " the in real time realization of theory wire loss Analysis System " (power informatization,, the 10th phase of the 5th volume, 63-65 page or leaf in 2007) _IjMethod, provided a kind of application process of online theory nework losses.

The Real-time Power Flow that above relates to electrical network calculates, He Yangzan, Wen Zengyin etc. are in " power system analysis (third edition) " (publishing house of the Central China University of Science and Technology, 2002) in discuss, trend calculate be the active power of electric parameter, power generator according to power transmission network topological structure, primary equipment and reactive power, etc. the active power of duty value and deciliter state of reactive power, circuit breaker and isolation plug-in strip and the switching state of secondary capacitor or low tension reactor calculate the active power of each equipment of power transmission network, the program of numerical calculation of reactive power.

After the AVC system drops into operation with closed ring, it is in the state of continuous closed-loop control, every electric network state of taking turns after the equal above wheel control strategy of control strategy is carried out is basic, therefore the numerical value that the power transmission network active loss that is caused by AVC reduces is the result who accumulates in continuous time, accurately calculates relatively difficulty.After AVC drops into closed-loop control simultaneously, can not arbitrarily AVC be withdrawed from closed-loop control and be analyzed.Therefore the quantitative analysis that the actual power transmission network active loss that causes of AVC system of closed-loop control is reduced is a difficult point always.And on the other hand, AVC owing to reasons such as generator and reactive apparatus outfits, may cause the AVC effect to be difficult to bring into play fully after dropping into operation with closed ring.The quantitative result of calculation that the operation maintenance personnel need to reduce in conjunction with the active loss that the AVC closed-loop control produces, improved suggestion is analyzed and provided to the various factors that affects the AVC operation, along with at present domestic power transmission network AVC at different levels system extensive use, cause that by AVC the quantitative calculation and analysis of power transmission network active loss reduction requires day by day urgent, not yet see at present in this respect relevant computational methods or achievement in research both at home and abroad.

Summary of the invention

The objective of the invention is to propose a kind of computational methods that caused power transmission network active loss reduction by automatism voltage control, it is characterized in that, the method may further comprise the steps:

(1) sets an automatism voltage control cycle T _c

(2) when begin every day, damage trend aggregate-value is fallen in automatism voltage control in the power transmission network

With the same day automatism voltage control fall and decrease the electric quantity accumulation value

Be set to respectively 0;

(3) when the automatism voltage control cycle arrives, it is t that note arrives constantly ₁, preserve the constantly t that arrives ₁Power transmission network operational parameter data bag, information in the power transmission network operational parameter data bag comprises: the electric parameter of power transmission network topological structure, power transmission network primary equipment, the active power of power generator and reactive power, etc. deciliter state of the active power of duty value and reactive power, power transmission network circuit breaker and isolation plug-in strip, and the switching state of power transmission network mesolow capacitor or low tension reactor;

(4) according to the constantly t that arrives ₁Power transmission network operational parameter data bag in information, adopt tidal current computing method, the power transmission network model is calculated, obtain active power and the reactive power of each branch road in the power transmission network model, thereby obtain total active power loss of power transmission network model

(5) from the automatic voltage control system of power transmission network, read constantly t of last automatism voltage control cycle arrival ₀The reactive power regulated quantity Δ Q that automatic voltage control system issues to every power generator _GiAnd the switching state of secondary capacitor to be controlled or low tension reactor;

(6) every the power generator reactive power regulated quantity Δ Q that reads according to step (5) _Gi, to the constantly t that arrives ₁Power transmission network operational parameter data bag in the reactive power of corresponding each power generator regulate, regulated quantity is-Δ Q _Gi

(7) secondary capacitor to be controlled that reads according to step (5) or the switching state of low tension reactor are to the constantly t that arrives ₁Power transmission network operational parameter data bag in secondary capacitor corresponding to be controlled or low tension reactor carry out reverse operating;

(8) according to adjusting and the operation of step (6) and step (7), adopt tidal current computing method, the power transmission network model is calculated, obtain active power and the reactive power of each branch road in the power transmission network model, thereby obtain total active power loss of power transmission network model

(9) according to above-mentioned total active power loss

With total active power loss

Obtain the difference of the total active power loss of power transmission network:

And will

The automatism voltage control that counts step (2) is fallen in the damage trend aggregate-value: $P_{\mathrm{sum}}^{\mathrm{loss}}=P_{\mathrm{sum}}^{\mathrm{loss}}+\mathrm{\Δ}{P}_{t1}^{\mathrm{loss}};$

(10) adopt Rectangular Method to carry out integration, obtain an automatism voltage control cycle T _cBe t ₀~ t ₁In period, because the changing value of the power transmission network active energy loss that automatic voltage control system causes:

$\mathrm{\Δ}{E}_{t1}^{\mathrm{loss}}=P_{\mathrm{sum}}^{\mathrm{loss}}\·T_c,$

And will

The automatism voltage control on the same day that counts step (2) is fallen in the damage electric quantity accumulation value:

$E_{\mathrm{sum}}^{\mathrm{loss}}=E_{\mathrm{sum}}^{\mathrm{loss}}+\mathrm{\Δ}{E}_{t1}^{\mathrm{loss}};$

(11) when the next automatism voltage control cycle arrives, return step (3), the beginning next round is calculated.

The present invention proposes a kind of computational methods that caused power transmission network active loss reduction by automatism voltage control, its characteristics and advantage are, the control strategy of inverse analog automatic voltage control system and carry out trend and calculate on power transmission network current state basis at first, obtain the power transmission network active power loss under the emulation mode, and compare with the active power loss of current virtual condition, obtain every reduction value that automatism voltage control control causes the power transmission network active power loss of taking turns; Secondly, every reduction value of taking turns the power transmission network active power loss that calculates is added up and carry out integration at time shaft, obtain the reduction value of power transmission network active energy loss in the continuous time, embodied automatic voltage control system and moved continuously the long lasting effect that power transmission network is produced.

Therefore the computational methods that adopt the present invention to propose, can on-line analysis calculate the numerical value that power transmission network active loss that the closed-loop control of AVC system causes reduces, thereby carry out the accurate quantitative analysis analysis by reducing the benefit that defeated power transmission network active loss brings after the AVC system put into operation, for operation maintenance personnel evaluation and the operation level that improves the AVC system provide scientific basis.

Embodiment

The present invention proposes a kind of computational methods that caused power transmission network active loss reduction by automatism voltage control, it is characterized in that, the method may further comprise the steps:

(1) sets an automatism voltage control cycle T _c

This cycle is the control cycle of automatic voltage control system, is generally 5 minutes and does not wait by 15 minutes, and when each control cycle arrives, automatic voltage control system will carry out control strategy and calculate, and issue control strategy to power plant or transformer station.This cycle can manually be set according to actual conditions and demand;

(2) when begin every day, damage trend aggregate-value is fallen in automatism voltage control in the power transmission network

With the same day automatism voltage control fall and decrease the electric quantity accumulation value

Be set to respectively 0;

Because the purpose of this method is the numerical value that reduces in the power transmission network active loss that line computation AVC system causes, and to the statistics of power transmission network active loss generally take day as unit, so the target of this method is to calculate in real time the numerical value that active loss that every day, the closed-loop control of AVC system caused reduces.

Be the reduction value of the active power loss that every day, AVC totally caused from 0 o'clock, the reduction value of the active power loss that each control cycle AVC causes all is accumulated to In.Right Carry out the rectangular integration of period, just can obtain the reduction value of the active energy loss that AVC accumulative total caused from 0 o'clock every day Since line computation and statistics take day as unit, therefore when begin every day, need to be 0 with these 2 amount values of putting.

(3) when the automatism voltage control cycle arrives, it is t that note arrives constantly ₁, preserve the constantly t that arrives ₁Power transmission network operational parameter data bag, information in the power transmission network operational parameter data bag comprises: the electric parameter of power transmission network topological structure, power transmission network primary equipment, the active power of power generator and reactive power, etc. deciliter state of the active power of duty value and reactive power, power transmission network circuit breaker and isolation plug-in strip, and the switching state of power transmission network mesolow capacitor or low tension reactor;

Power transmission network operational parameter data bag is a kind of medium of storing the power transmission network operation information that this method adopts.A power transmission network operational parameter data bag has comprised complete power transmission network topological structure, power transmission network electrical parameters of equipment and the current running state information of power transmission network.Trend calculating in this method just is based on this power transmission network operational parameter data bag and carries out.Because each cycle of power transmission network operational parameter data bag has deposited in the commercial data base, therefore this method is except being used for line computation, also can be with the power transmission network operational parameter data bag of preserving in the database, the numerical value that the active power loss that certain AVC system closed-loop control in historical day of appointment is caused reduces carries out off-line analysis and calculating.

(4) according to the constantly t that arrives ₁Power transmission network operational parameter data bag in information, adopt tidal current computing method, the power transmission network model is calculated, obtain active power and the reactive power of each branch road in the power transmission network model, thereby obtain total active power loss of power transmission network model

The equation that trend is calculated is:

$\left\{\begin{array}{c}{P}_{\mathrm{Gi}}-P_{\mathrm{Di}}-V_i\underset{j\∈I}{\mathrm{\Σ}}{V}_j(G_{\mathrm{ij}}\cos {\mathrm{\θ}}_{\mathrm{ij}}+B_{\mathrm{ij}}\sin {\mathrm{\θ}}_{\mathrm{ij}})=0\\ Q_{\mathrm{Gi}}-Q_{\mathrm{Di}}-V_i\underset{j\∈I}{\mathrm{\Σ}}{V}_j(G_{\mathrm{ij}}\sin {\mathrm{\θ}}_{\mathrm{ij}}-B_{\mathrm{ij}}\cos {\mathrm{\θ}}_{\mathrm{ij}})=0\\ i=1,...,\mathrm{NB}{\mathrm{\θ}}_s=0\end{array}\right.---\left(1\right)$

In the formula, NB is all node set in the described electrical network, and S is reference node, P _GiAnd Q _GiBe respectively the meritorious and reactive power generation power output of described NB interior nodes i, P _DiAnd Q _DiBe respectively burden with power and the load or burden without work of described NB interior nodes i, V _iAnd V _jBe the voltage magnitude of described NB interior nodes i and j, set I represents the node set that all and node i have branch road to be connected, G _Ij, B _IjFor the electricity between described NB interior nodes i and the node j is led, susceptance, θ _Ij=θ _i-θ _jBe the phase angle difference between node i and the node j.During trend is calculated, known P _GiQ _GiP _DiQ _Di, and G _Ij, B _Ij, P wherein _GiQ _GiP _DiQ _DiBe the running status of electrical network, G _Ij, B _IjBe the parameter of branch road, all from the holographic profile data bag of preserving in the step (3), the unknown quantity of finding the solution is V to this tittle _iAnd θ _iTotal N mode equation number and N unknown number can in the hope of deciding solution, obtain the V of all nodes by numerical computation method _iAnd θ _iAfter, by the Branch Power Flow computing formula:

$P_{\mathrm{ij}}=V_i^2{G}_{\mathrm{ij}}-V_i{V}_j(G_{\mathrm{ij}}\cos {\mathrm{\θ}}_{\mathrm{ij}}+B_{\mathrm{ij}}\sin {\mathrm{\θ}}_{\mathrm{ij}})$

$Q_{\mathrm{ij}}=-V_i^2(B_{\mathrm{ij}}+y_c)-V_i{V}_j(G_{\mathrm{ij}}\sin {\mathrm{\θ}}_{\mathrm{ij}}-B_{\mathrm{ij}}\cos {\mathrm{\θ}}_{\mathrm{ij}})---\left(2\right)$

Can calculate the meritorious trend P of each branch road _Ij, pass through following formula:

$P_{t1}^{\mathrm{loss}}=\underset{(i,j)\∈\mathrm{NL}}{\mathrm{\Σ}}(P_{\mathrm{ij}}+P_{\mathrm{ji}})$

Can calculate constantly t ₁The meritorious trend loss of electrical network

Wherein NL is all set that produce the branch road of active loss in the power transmission network, P _IjAnd P _JiBe the active power at branch road (i, the j) two ends of i node to the j node in the power transmission network, itself and be the active power loss of this branch road.

(5) from the automatic voltage control system of power transmission network, read constantly t of last automatism voltage control cycle arrival ₀The reactive power regulated quantity Δ Q that automatic voltage control system issues to every power generator _GiAnd the switching instruction of secondary capacitor to be controlled or low tension reactor;

The main website of AVC system partly realizes based on software in Power System Control Centers, and its voltage control strategy to power transmission network mainly contains to the idle control strategy of power generator and to control strategy 2 classes of the reactive apparatus of transformer station.

The AVC system is by calculating the idle regulated quantity Δ Q of each unit of power plant _GiAfter, send by the AVC substation system of data communication channel to power plant, after the AVC substation of power plant receives the generator reactive adjustment amount, running status according to each generator in the current power plant, adopt step-by-step system to adjust the reactive power that generator sends, until reach the adjustment amount that the AVC main website issues.During idle increase (minimizing) that generator sends, high-voltage side bus voltage raise (reduction).

In the AVC main website, every control cycle of taking turns all will calculate and issue the generator reactive control strategy, and every each generator reactive adjustment amount of taking turns in the strategy deposits commercial data base in simultaneously.By reading commercial data base, can obtain the idle adjustment amount of each power generator that last cycle AVC issues.

The AVC main website is switching instruction to Substation Reactive-power Compensation equipment to the control strategy of transformer station, and reactive-load compensation equipment mainly comprises secondary capacitor and low tension reactor, and when dropping into capacitor or excision reactor, busbar voltage raises; When the excision capacitor or after dropping into reactor, the busbar voltage reduction.The AVC main website issues and drops into or the instruction of excision reactive apparatus, and the Automatic monitoring systems transformer station in are according to the instruction that receives, and the circuit breaker that finds reactive-load compensation equipment to connect closes circuit breaker or disconnects, with input or excise reactive-load compensation equipment.

In the AVC main website, whenever take turns the control strategy that control cycle is all wanted calculable capacitor or reactor, calculate capacitor or the reactor that needs control and issue control command, the capacitor or the reactor that need simultaneously to control deposit in the commercial data base.By reading commercial data base, can obtain capacitor to be controlled that last cycle AVC issues or the switching instruction of reactor.

(6) every the reactive power regulated quantity Δ Q that reads according to step (5) _Gi, to the constantly t that arrives ₁Power transmission network operational parameter data bag in the reactive power of corresponding each power generator regulate, regulated quantity is-Δ Q _Gi

The power transmission network operational parameter data bag of preserving in step (3) is constantly t of current period arrival ₁Data, the constantly t that arrives of last automatism voltage control cycle namely ₀Produce the running status of the complete rear power transmission network of control strategy.In the trend of step (3) is calculated, the idle Q that exerts oneself of generator _GiBe the result of last periodic Control strategy execution after finishing.If the last cycle is to the idle Δ Q that is adjusted to of i generator _Gi, then in power transmission network operational parameter data bag, the reactive power flow of i generator exerted oneself in this step and carry out reverse adjusting, as follows:

Q′ _Gi=Q _Gi-ΔQ _Gi （3）

Be that regulated quantity is-Δ Q _Gi, this regulated quantity has been simulated the control strategy of last cycle AVC system and " has been carried out " in the situation idle value of exerting oneself of each generator.

(7) secondary capacitor to be controlled that reads according to step (5) or the switching state of low tension reactor are to the constantly t that arrives ₁Power transmission network operational parameter data bag in secondary capacitor corresponding to be controlled or low tension reactor carry out reverse operating;

Read the control strategy of last cycle of AVC system to power transmission network transformer station secondary capacitor or low tension reactor in the step (4), i.e. the switching instruction of capacitor or reactor.Capacitor and reactor are presented as over the ground branch road in electric network swim calculates, drop into or withdraw from impact that capacitor, reactor calculate electric network swim and be embodied in B in formula (1) and the formula (2) _IiB is passed through in the variation of (being the situation of i=j in the formula) _IiVariation can affect the result that trend is calculated.Before carrying out trend calculating, program can according to the switching of capacitor and reactor, be calculated and also revise B at every turn _Ii

The power transmission network operational parameter data bag of preserving in step (3) is constantly t of current period arrival ₁Data, the constantly t that arrives of last automatism voltage control cycle namely ₀The running status of the complete rear power transmission network of control strategy of the AVC that produces, so in the trend of step (3) is calculated, B _IiThe equipment switching of switching instruction after complete that is the capacitor that produces according to last control cycle or reactor calculates.

Owing to carrying out before trend calculates at every turn, the circuit breaker that program can be connected according to capacitor and reactor and the state of disconnecting link are judged the running status of capacitor and reactor, calculate and also revise B _Ii, therefore in this step, do not need directly to revise B _Ii, only need according to the capacitor in last cycle and reactor throwing, cut control strategy oppositely insert capacitor and reactor institute connecting valve minute, the state of closing gets final product.

(8) according to adjusting and the operation of step (6) and step (7), adopt tidal current computing method, the power transmission network model is calculated, obtain active power and the reactive power of each branch road in the power transmission network model, thereby obtain total active power loss of power transmission network model

Recomputate trend according to formula (1), at this moment the generator reactive power in the power flow equation of power transmission network model output has not been the idle output of current actual power transmission network running status, but the idle Q ' that exerts oneself after in step (6), carrying out analog regulation according to (4) formula _Gi, the B in the while power flow equation _IiNeither parameter corresponding to actual power transmission network running status, but carry out the B ' that calculates after the inverse analog operation according to the running status of the capacitor that in the step (7) i node is connected or reactor _Ii, namely power flow equation becomes:

$\left\{\begin{array}{c}{P}_{\mathrm{Gi}}-P_{\mathrm{Di}}-V_i^{\′}\underset{j\∈I}{\mathrm{\Σ}}{V}_j^{\′}(G_{\mathrm{ij}}\cos {\mathrm{\θ}}_{\mathrm{ij}}^{\′}+B_{\mathrm{ij}}^{\′}\sin {\mathrm{\θ}}_{\mathrm{ij}}^{\′})=0\\ Q_{\mathrm{Gi}}^{\′}-Q_{\mathrm{Di}}-V_i^{\′}\underset{j\∈I}{\mathrm{\Σ}}{V}_j^{\′}\left(G_{\mathrm{ij}}\sin {\mathrm{\θ}}_{\mathrm{ij}}^{\′}\text{-}{B}_{\mathrm{ij}}^{\′}\cos {\mathrm{\θ}}_{\mathrm{ij}}^{\′}\right)=0\\ i=1,...,\mathrm{NB}{\mathrm{\θ}}_s=0\end{array}\right.---\left(4\right)$

Can obtain new solution V ' _iAnd θ ' _iAfter, in the substitution formula (2), can obtain the meritorious trend P ' of each branch road _Ij, pass through following formula:

$P_{t0}^{\mathrm{loss}}=\underset{(i,j)\∈\mathrm{NL}}{\mathrm{\Σ}}(P_{\mathrm{ij}}^{\′}+P_{\mathrm{ji}}^{\′})$

Can calculate the rear power transmission network electric network active trend loss of analog regulation operation

(9) according to above-mentioned total active power loss

With total active power loss

Obtain the difference of the total active power loss of power transmission network:

And will The automatism voltage control that counts step (2) is fallen in the damage trend aggregate-value: $P_{\mathrm{sum}}^{\mathrm{loss}}=P_{\mathrm{sum}}^{\mathrm{loss}}+\mathrm{\Δ}{P}_{t1}^{\mathrm{loss}};$

Calculate

Physical significance be that if the control strategy of the upper wheel of AVC is not carried out, then power transmission network active power loss value is

Active power loss value with current power transmission network reality Poor, for the numerical value that the power transmission network active power loss value that causes of control reduces is taken turns by this by the AVC system.

Will

Be added to In physical significance be: because the AVC system carries out continuously to the closed-loop control of power transmission network, every take turns control all be take turns control strategy complete after, electrical network proceeds after entering into a new state, it is therefore every that to take turns impact that control strategy produces electrical network be continuous action at thereafter time interval, being reduced in thereafter period of the active power loss of its generation is still effective, has embodied the accumulative effect that active loss reduces.

It should be noted that the AVC system is to reduce the power transmission network active power loss as the control target, therefore generally speaking

But because the control target of AVC system is guaranteeing that power transmission network voltage reduces active power loss in qualified, be not every the wheel therefore

All be positive, the AVC system is qualified in order to guarantee power transmission network voltage sometimes, and the control strategy of some period can cause network loss to increase, namely

But from accumulative effect, Positive in most of periods, namely represent the AVC system when the overall benefit of day operation for reducing active power loss.

(10) adopt Rectangular Method to carry out integration, obtain an automatism voltage control cycle T _cBe t ₀~ t ₁In period, because the changing value of the power transmission network active energy loss that automatic voltage control system causes:

$\mathrm{\Δ}{E}_{t1}^{\mathrm{loss}}=P_{\mathrm{sum}}^{\mathrm{loss}}\·T_c$

And will

The automatism voltage control on the same day that counts step (2) is fallen in the damage electric quantity accumulation value:

$E_{\mathrm{sum}}^{\mathrm{loss}}=E_{\mathrm{sum}}^{\mathrm{loss}}+\mathrm{\Δ}{E}_{t1}^{\mathrm{loss}};$

In step (9), calculate

Be the aggregate-value that current power transmission network active power loss reduces, its dimension is kilowatt (kW), with the aggregate-value of current active power loss reduction

Time shaft is carried out rectangular integration, and the time step of integration is T _c, can obtain the aggregate-value that the loss of power transmission network active energy reduces within this period, dimension is kilowatt hour (kWH).Each control cycle be exactly a step-length of rectangular integration, the continuous computational process of whole day is to variable

Carry out the process of integration at the time shaft of whole day.

(11) when the next automatism voltage control cycle arrives, return step (3), the beginning next round is calculated.

In the inventive method, calculating

Be the reduction value of the power transmission network active energy loss of i control cycle automatic voltage control system generation,

Be the reduction value of the power transmission network active energy loss of whole day accumulative total, these 2 amounts have provided the quantitative values that power transmission network active loss that automatism voltage control produces reduces, and can calculate corresponding economic benefit value according to Settlement price.

Therefore the inventive method is to calculate online continuously, can provide the aggregate-value that the power transmission network active energy loss that caused by closed-loop control to current time AVC system from 0 o'clock every day reduces constantly in the arrival of each control cycle The benefit that the active loss that the AVC system is produced reduces has provided online, quantitative analysis result.

Claims (1)

1. computational methods that caused power transmission network active loss reduction by automatism voltage control is characterized in that, the method may further comprise the steps:

(1) sets an automatism voltage control cycle T _c

(2) when begin every day, damage trend aggregate-value is fallen in automatism voltage control in the power transmission network

With the same day automatism voltage control fall and decrease the electric quantity accumulation value

Be set to respectively 0;

(3) when the automatism voltage control cycle arrives, it is t that note arrives constantly ₁, preserve the constantly t that arrives ₁Power transmission network operational parameter data bag, information in the power transmission network operational parameter data bag comprises: the electric parameter of power transmission network topological structure, power transmission network primary equipment, the active power of power generator and reactive power, etc. deciliter state of the active power of duty value and reactive power, power transmission network circuit breaker and isolation plug-in strip, and the switching state of power transmission network mesolow capacitor or low tension reactor;

(4) according to the constantly t that arrives ₁Power transmission network operational parameter data bag in information, adopt tidal current computing method, the power transmission network model is calculated, obtain active power and the reactive power of each branch road in the power transmission network model, thereby obtain total active power loss of power transmission network model

(5) from the automatic voltage control system of power transmission network, read constantly t of last automatism voltage control cycle arrival ₀The reactive power regulated quantity Δ Q that automatic voltage control system issues to every power generator _GiAnd the switching state of secondary capacitor to be controlled or low tension reactor;

(6) every the power generator reactive power regulated quantity Δ Q that reads according to step (5) _Gi, to the constantly t that arrives ₁Power transmission network operational parameter data bag in the reactive power of corresponding each power generator regulate, regulated quantity is-Δ Q _Gi

(7) secondary capacitor to be controlled that reads according to step (5) or the switching state of low tension reactor are to the constantly t that arrives ₁Power transmission network operational parameter data bag in secondary capacitor corresponding to be controlled or low tension reactor carry out reverse operating;

(8) according to adjusting and the operation of step (6) and step (7), adopt tidal current computing method, the power transmission network model is calculated, obtain active power and the reactive power of each branch road in the power transmission network model, thereby obtain total active power loss of power transmission network model

(9) according to above-mentioned total active power loss With total active power loss

Obtain the difference of the total active power loss of power transmission network:

And will

The automatism voltage control that counts step (2) is fallen in the damage trend aggregate-value: $P_{\mathrm{sum}}^{\mathrm{loss}}=P_{\mathrm{sum}}^{\mathrm{loss}}+\mathrm{\Δ}{P}_{t1}^{\mathrm{loss}};$

(10) adopt Rectangular Method to carry out integration, obtain an automatism voltage control cycle T _cBe t ₀~ t ₁In period, because the changing value of the power transmission network active energy loss that automatic voltage control system causes:

$\mathrm{\Δ}{E}_{t1}^{\mathrm{loss}}=P_{\mathrm{sum}}^{\mathrm{loss}}\·T_c,$

And will

The automatism voltage control on the same day that counts step (2) is fallen in the damage electric quantity accumulation value:

$E_{\mathrm{sum}}^{\mathrm{loss}}=E_{\mathrm{sum}}^{\mathrm{loss}}+\mathrm{\Δ}{E}_{t1}^{\mathrm{loss}};$

(11) when the next automatism voltage control cycle arrives, return step (3), the beginning next round is calculated.