CN105896618A - Operating method for energy storage power generation system capable of adjusting reactive power - Google Patents

Abstract

The invention discloses an operating method for an energy storage power generation system capable of adjusting reactive power. According to the operating method, a power generation apparatus, a load unit, an energy storage apparatus and SVG equipment are monitored concurrently; the power fluctuation value of the energy storage power generation system is collected in time; and the power fluctuation value is taken as the information source to dynamically adjust the power of the energy storage apparatus so as to smoothen the power of the grid-connection point and to improve the economical operation of the energy storage power generation system.

Description

A kind of operation method that can be used for regulating idle energy-storing and power-generating system

Art

The present invention relates to a kind of operation method that can be used for regulating idle energy-storing and power-generating system.

Background technology

Along with increasing and the propelling of developing country's process of industrialization of earth population, various fossil energies are rapid Exhaustion, and atmospheric pollution and Ecological Environment Crisis that fossil energy causes during using are the most serious.For Reduce atmospheric pollution, the supply steady in a long-term of the energy of preserving the ecological environment, ensure, be altered in steps existing Energy resource structure, greatly developing green energy resource has become the common recognition of various countries.

Along with the maturation of the renewable energy power generation technology such as wind-power electricity generation, photovoltaic generation, wave-activated power generation, more come The most regenerative resource energy-storing and power-generating system form in a distributed manner accesses electrical network, meet the daily production of people, The demand of household electricity.

Micro-grid system smooths and site power swing often through configuration energy-storage battery, improves electrical network to micro- The receiving ability of net system.In light storage micro-grid system, a part of capacity of energy-storage battery is used as the appearance of emergency service Amount, another part capacity is for the smooth and power swing of site.

Along with wind-powered electricity generation large-scale grid connection, its power swing is more and more prominent to the impact of electrical network.And energy-storage system The feature the most quickly absorbing and releasing energy having, it is possible to effectively make up wind power output power intermittent, The shortcoming of undulatory property, therefore configures energy-storage system in wind power-generating grid-connected system and has become as that to stabilize wind-powered electricity generation defeated One of effective means going out power swing.

Owing to energy-storage system is relatively costly, how to select the maximum economic use value playing energy-storage system, with Shi Tigao energy-storage system service life, become wind-powered electricity generation and run the problem that enterprise is badly in need of considering.Mixed energy storage system The ripple components of special frequency channel a certain in Power Output for Wind Power Field can be compensated, thus realize wind-powered electricity generation merit Rate fluctuation is stabilized.Energy storage setting power is divided into frequent fluctuation part and smooth, respectively by super capacitor Undertake with energy-storage battery, it is possible to achieve to the quick response stabilizing demand.

In order to optimize the operational efficiency of microgrid and for distribution quality, it is the most best that microgrid incorporates external electrical network Selection, it can maintain local power optimization and balance, reduce system run manual dispatching difficulty. But, the generator unit in microgrid and load cell are only monitored by prior art, not to energy-storage system Effectively monitor, it is impossible to the battery-operated state in regulation energy-storage system in time, easily cause microgrid with outer The also site power swing of portion's electrical network is relatively big, and the unstable safety and reliability to distribution of power supply brings bad Impact.

Summary of the invention

The present invention provides a kind of operation method that can be used for regulating idle energy-storing and power-generating system, and the method can be led to Cross and TRT, load unit, energy storage device and SVG equipment are monitored in the lump, timely energy-storing and power-generating system Power swing value, and the power of energy storage device is dynamically regulated as information source, thus realize smooth and site Power, improves energy-storing and power-generating system economical operation.

To achieve these goals, the present invention provides the operation method of a kind of energy-storing and power-generating system, the method bag Include following steps:

S1. TRT monitoring module obtains TRT service data in real time, and stores data, obtains in real time Load power demand situation in energy-storing and power-generating system, obtains the power attenuation situation of energy storage device in real time；

S2. according to load power demand situation, energy storage device in TRT service data, energy-storing and power-generating system Power attenuation situation, be predicted the TRT output in following predetermined instant is meritorious and idle；

S3. gather grid-connected point voltage information, determine that energy-storing and power-generating system is gained merit according to bulk power grid dispatch command simultaneously And idle output demand；

S4. bearing power in meritorious and idle for energy-storing and power-generating system output demand, current energy-storing and power-generating system is needed Ask, TRT is exportable meritorious and idle, exportable idle, the power attenuation of energy storage device of SVG equipment Situation is as constraints, it is achieved the idle work optimization of energy-storing and power-generating system runs, and suppresses voltage pulsation.

Preferably, in step s 2, before accessing bulk power system, TRT monitoring module obtains energy storage Electricity generation system ingredient basic data, the most quantitative in Theoretical Calculation object function；Join based on TRT Number, builds TRT mathematical model, does early-stage preparations for calculating TRT loss, obtains storage further The internal each several part physical parameter of energy electricity generation system, builds whole energy-storing and power-generating system mathematical model.

Preferably, in step s 4, idle work optimization runs and specifically includes following steps:

S41. by TRT monitoring module, obtain TRT running status in energy-storing and power-generating system, gain merit Performance number, the real time data of energy storage device of energy-storing and power-generating system, energy-storing and power-generating system data acquisition during this Integrate frequency range as 10s-60s, extract data and go forward side by side row filter, reject and shut down or there is fault TRT number According to；Based on real time data, set up energy-storing and power-generating system reactive power and voltage control model；Parallel control module The energy-storing and power-generating system grid-connected point voltage instruction assigned according to dispatching patcher, if superior system does not assign instruction, Then by the given instruction of middle control module；Change with the time scale of reactive power and select two kinds of control models；

If the most idle change yardstick changes with minute/hour level time scale, TRT control mode is turned It is changed to constant active power controller, with energy-storing and power-generating system economical operation for controlling target, sets up object function, S1 and S41 fetched data is substituted in model, carries out TRT without the distribution of work；

S43. solve object function, obtain TRT Reactive-power control value；According to also site real-time voltage, design Management process, is divided into five grades by the voltage in adjustable extent, the corresponding different Reactive-power control of each grade Amount, according to the running status that each TRT is different, is assigned to sending out of correspondence by the reactive power value obtained Electric installation；

If the most idle change yardstick is with millisecond/second level time scale change, TRT operational mode is switched For constant voltage control mode；With suppression voltage pulsation as target, set up object function, by S1 and S31 institute Obtain data to substitute in model, carry out TRT without the distribution of work；

S45. in energy-storing and power-generating system, each unit receives Reactive power control instruction, completes according to self corresponding situation Instruction, after performing instruction, feeds back to dispatching patcher by response value and grid-connected point voltage.

Preferably, by supervising device in S41, obtain energy-storing and power-generating system real time data and PCC point voltage Control instruction, arranges PCC point voltage fluctuation threshold values；

Δ U=| U_WFcmd-U_WFout|≤ξ

In formula, U_WFcmdFor energy-storing and power-generating system site desired voltage values；U_WFoutFor energy-storing and power-generating system also Site real-time voltage value；ξ is energy-storing and power-generating system voltage threshold；Δ U is grid-connected point voltage deviation value.

Preferably, in S42, set up the idle work optimization function being assigned as target with energy-storing and power-generating system economic optimization:

Min (F)=w₁P_loss+w₂Q_C+λ₁ΔU_i+λ₂ΔQ

In formula, P_lossFor energy-storing and power-generating system active loss；Q_CFor SVG equipment investment capacity；ΔU_iFor respectively Node voltage gets over limit value；ΔQ_iSend reactive power for TRT and get over limit value；w₁And w₂For active power loss and The weight factor of reactive compensation capacity, and w₁+w₂=1；λ is penalty factor, is calculating optimal function, is rising To restricted problem.

Preferably, S42 is analyzed calculate, first carries out calculating energy-storing and power-generating system Load flow calculation；According to Energy-storing and power-generating system reactive power dimensional variation in time, determines TRT control model, in second/hour level Time, TRT control mode is converted to power limitation control, calculates TRT to reduce network loss as mesh Idle adjustable nargin under Biao, it is ensured that bound for objective function；Set up energy-storing and power-generating system economical operation For the idle control mathematical model of target, by S1 and S41 the data obtained, substitute in model；

The copper loss of the loss of TRT predominantly TRT, its expression formula is:

$P_{cu}=R_s(I_{sq}^2+I_{sd}^2)+R_r(I_{rd}^2+I_{rq}^2)$

In formula, R_sFor generator unit stator resistance, R_rFor generator amature resistance, I_sFor stator current, I_rFor turning Electron current；

In transmission of electricity energy-storing and power-generating system, load is represented by ∏ shape equivalent circuit, load in series in energy-storing and power-generating system Active loss be directly proportional to the current squaring passed through to reactive loss, it may be assumed that

${\mathrm{\ΔP}}_L=\frac{P_1^2+Q_1^2}{U_1^2}R$

${\mathrm{\ΔQ}}_L=\frac{P_1^2+Q_1^2}{U_1^2}X$

U₂For PCC junction point voltage in energy-storing and power-generating system, load in one section of transmission energy-storing and power-generating system Afterwards with bulk power grid before step voltage U₁It is connected；Voltage U₂Active power and the reactive power injected with access point have Close；When fluctuation occurs in wind speed, stablizing of system PCC point busbar voltage can be affected, due to busbar voltage Fluctuation, can increase the network loss of energy-storing and power-generating system, cause economic loss, when fluctuation is more than 10%, and can be to storage The output of energy electricity generation system produces impact, so needing the reactive power of PCC point is regulated and controled, from And maintain U₂Constant；

Under stable situation, energy-storing and power-generating system is incorporated into the power networks, and now energy-storing and power-generating system carries for accessing bulk power grid For electric energy, using unity power factor control, whole energy-storing and power-generating system does not exchanges reactive power with electrical network； Power system voltage regulating depends on TRT, energy storage device and electrical network parameter etc., is determined by reactive requirement, Regulate its stator voltage, with rotor current；

For the purpose of electricity generation system active loss, set up object function:

P_loss=P₁+P₂+P₃

$P_1=\underset{i=1}{\overset{n}{\Σ}}{P}_{cui}$

$P_2=\left\{\underset{i=1}{\overset{n}{\Σ}}\frac{(P_{mi}^2+Q_{mi}^2)(R_{Ti}+R_{Li})}{U_i^2}\right\}$

P₃=P_LT

In formula, P_mi, Q_miIt is respectively i-th doubly-fed generation device and injects meritorious, the idle injection rate of bus bar side； U is that case becomes high side bus voltage；R_Ti, R_LiIt is respectively conversion and becomes on high-tension side resistance and current collection energy storage to case Load resistance in electricity generation system；P₁For TRT copper loss；P₂For load loss in energy-storing and power-generating system；P₃ The active loss of energy storage device.

Preferably, with energy-storing and power-generating system loss minimization as principle, it is contemplated that every TRT active loss, TRT active loss is mainly stator and rotor copper loss, and wherein stator current is:

$I_{si}^2=\frac{\sqrt{({P_i}^2+{Q_i}^2)}}{3U_i}$

Rotor current is:

$I_{ri}=\frac{1}{X_{mi}}\sqrt{\[I_{si}^2(R_{si}^2+X_{li}^2)+U_i^2+2U_i(\frac{P_i{R}_{si}}{3U_i}-\frac{Q_i{X}_{li}}{3U_i})\]}$

$P_{cui}=3I_{si}^2{R}_{si}+3I_{ri}^2{R}_{ri}$

By P_cuiIt is organized into about Q_iOne-place 2-th Order expression formula

$P_{cui}={\mathrm{aQ}}_i^2+{\mathrm{bQ}}_i+c$

$\left\{\begin{array}{c}a=\frac{X_{mi}^2{R}_{si}+R_{si}^2{R}_{ri}+X_{li}^2{R}_{ri}}{3U_i^2{X}_{mi}^2}\\ b=\frac{2X_{li}{R}_{ri}}{X_{mi}^2}\\ c=\frac{(R_{si}{X}_{mi}^2+R_{si}^2{R}_{ri}+X_{li}^2{R}_{ri})P_i^2+6R_{si}{R}_{ri}{U}_i^2{P}_i+9R_{ri}{U}_i^4}{3X_{mi}^2{U}_i^2}\end{array}\right.$

In formula, U_iIt it is the stator terminal voltage of i-th TRT；X_1i=X_si+X_mi, X_2i=X_ri+X_mi, its In, X_si、X_m、X_riIt is respectively the stator leakage reactance of i-th TRT, excitation leakage reactance and rotor leakage reactance；

In energy-storing and power-generating system, the active loss reactive loss in load is expressed as:

$P_{Li}=Q_{Li}\frac{R_i}{X_i}$

In formula, Q_LiFor connecting bus in energy-storing and power-generating system to TRT line concentration and the idle damage of energy storage device Consumption value；

The active loss reactive loss of energy storage device is indicated:

$P_{LT}=P_0+P_k(\frac{100Q_{LT}}{S_N{U}_k\%}-\frac{I_O\%}{U_k\%})$

To sum up, bear in TRT, energy storage device, energy-storing and power-generating system in proposition comprises energy-storing and power-generating system It is loaded in the object function that interior active power loss is minimum:

Min (F)=w₁P_loss+w₂Q_C+λ₁ΔU_i+λ₂ΔQ

In formula, P_lossFor energy-storing and power-generating system active loss；Q_CFor SVG equipment investment capacity；ΔU_iFor respectively Node voltage gets over limit value；ΔQ_iSend reactive power for TRT and get over limit value；w₁And w₂For active power loss and The weight factor of reactive compensation capacity, and w₁+w₂=1；With for penalty factor.

Preferably, wherein the trend constraints of Optimized model is:

$P_i=U_i\underset{j=1}{\overset{n}{\Σ}}{U}_j(G_{ij}{\mathrm{cos\θ}}_{ij}+B_{ij}{\mathrm{sin\θ}}_{ij})$

$Q_i=U_i\underset{j=1}{\overset{n}{\Σ}}{U}_j(G_{ij}{\mathrm{cos\θ}}_{ij}-B_{ij}{\mathrm{sin\θ}}_{ij})$

Idle equality constraint is

$\underset{i=1}{\overset{n}{\Σ}}(Q_{mi}-{\mathrm{\ΔQ}}_i)-Q_{LT}=Q_{ref}$

Inequality constraints

$0\≤P_i\≤P_{imax}^{ref}$

Q_imin≤Q_i≤Q_imax

V_i ^ref-V_i ^err≤V_i≤V_i ^ref+V_i ^err

In formula,It is that i-th TRT maximum predicted sends power, Q_imaxIdle for TRT maximum Output valve, Q_iminFor the minimum idle output valve of TRT, V_i ^errFor node voltage fluctuation range.

Preferably, in step S43, grid-connected point voltage perunit value is divided into different brackets, respectively U_a、 U_b、U₀、U_c、U_d, using different grades of busbar voltage as amplitude limit, whole control process is managed, Ensure, during reducing network loss, to take into account busbar voltage quality；Make U₀=1, i.e. occur without under abnormal conditions Busbar voltage, makes U_b、U_cIt is respectively U₀± 5%, make U_a、U_dIt is respectively U₀± 10%；

(1) U is worked as₂When being in voltage magnitude bottom half；

1)U₂≤U_aTime, PCC point voltage reaches the lower limit that fluctuates, and needs energy-storing and power-generating system to provide reactive power, Improving voltage, TRT control mode is converted to constant voltage control；

2)U_a≤U₂≤U_bTime, it is desirable to provide reactive power reduces energy-storing and power-generating system network loss, but still needs to nothing Merit power assurance voltage, TRT is idle is output as in now regulation

$Q=\frac{2U_b-U_2}{U_b}{Q}_{mi}$

3)U_b≤U₂≤U₀Time, this interval busbar voltage grade meets demand, and TRT provides reactive power Reducing network loss, TRT is idle is output as in now regulation

Q=Q_m

(2) U is worked as₂When being in voltage magnitude upper half, regulation process is similar with flow process (1).

Preferably, in described step S44, set up the idle work optimization function of suppression multiple target voltage pulsation

$Q_{ref}=K_{ref}^U(U_{mea}-U_{ref})+\underset{0}{\overset{T_{ref}^U}{\∫}}(U_{mea}-U_{ref})dt+K_{RX}\[\frac{\underset{0}{\overset{T_{\mathrm{int}}}{\∫}}(P_{avg}-P_{mea})dt}{T_{\mathrm{int}}}\]$

In formula, U_meaFor also site actual measurement voltage, U_refFor voltage reference value,For Control of Voltage gain system Number,For voltage error integration time constant, K_RXFor reactive power compensation gain coefficient, T_intDuring for controlling Between yardstick.

The energy storing and electricity generating method of the present invention have the advantage that (1) can by TRT, load unit, Energy storage device and SVG equipment are monitored in the lump, timely energy-storing and power-generating system power swing value, and as information Source dynamically regulates the power of energy storage device, thus realizes smooth and site power；(2) energy storing and electricity generating system is realized The economical operation of system, and suppression voltage pulsation, by the collection to energy-storing and power-generating system data, set up net Network framework model, under power limitation control strategy, it is ensured that TRT power factor is constant, by idle tune Control economical operation.

Accompanying drawing explanation

Fig. 1 shows a kind of block diagram that can be used for regulating idle energy-storing and power-generating system of the present invention；

Fig. 2 shows the operation method of the energy-storing and power-generating system of a kind of present invention.

Detailed description of the invention

Fig. 1 shows a kind of can be used for of the present invention and regulates idle energy-storing and power-generating system 10, and this energy storage is sent out Electricity system includes: TRT 12, for green energy resource is converted into electric energy；This TRT is preferably wind Power generator group；Load 14 in energy-storing and power-generating system；Energy storage device 15, is used for storing energy, and can send out When electricity system is incorporated into the power networks, output；SVG equipment 13, for providing for energy-storing and power-generating system 10 Reactive power；AC/DC bus, for realizing TRT in electricity generation system, energy storage device, energy storage Power Exchange 16 between loading in electricity generation system；Grid-connecting apparatus 17, is used for realizing energy-storing and power-generating system 10 And the Power Exchange 20 between bulk power grid；With supervising device 11.

This supervising device 11 includes:

TRT monitoring module 113, for monitoring TRT 12 in real time, and sending out TRT 12 Electrical power is predicted；

Parallel control module 112, for monitoring site ac bus voltage, and is used for controlling energy storing and electricity generating system System 10 is incorporated into the power networks via grid-connecting apparatus 17；

Energy storage device monitoring module 117, for the power attenuation situation of monitoring energy storage device 15 in real time；

Load monitoring module 114, the load 14 in monitoring energy-storing and power-generating system in real time；

SVG monitoring module 115, for monitoring SVG equipment 13 in real time；

Middle control module 116, for determining the operation method of energy-storing and power-generating system, and in above-mentioned supervising device Each module sends instruction, to perform this operation method；

Communication bus 111, for the liaison of the modules of this supervising device.

Preferably, described energy storage device 15 include first kind bidirectional power converter, first kind energy storage device, Equations of The Second Kind bidirectional power converter and Equations of The Second Kind energy storage device；

First kind bidirectional power converter, for obtaining the parameter of the physical parameter on described AC/DC bus Value, and when described parameter value changes, change first according to the rate of change of default charge/discharge rates Class energy storage device carries out charge/discharge rates during discharge and recharge；Until the parameter value of described physical parameter is equal to first Parameter value or equal to the second parameter value time, first kind energy storage device is carried out charge/discharge rates during discharge and recharge No longer change；

Equations of The Second Kind bidirectional power converter, for obtaining the parameter value of described physical parameter, and in described parameter When value arrives the boundary value of preset range, Equations of The Second Kind energy storage device is carried out discharge and recharge so that described parameter value Maintain the boundary value of preset range, described first parameter value and described second parameter value and be respectively positioned on described presetting In the range of.

Preferably, according to the rate of change change of default charge/discharge rates, first kind energy storage device is carried out charge and discharge Charge/discharge rates during electricity includes two kinds of situations, and the first situation is: according to the change of default charging rate Rate changes charging rate when being charged first kind energy storage device；The second situation is: according to default The rate of change of the velocity of discharge changes velocity of discharge when discharging first kind energy storage device.

Preferably, the energy density of first kind energy storage device is higher than the energy density of Equations of The Second Kind energy storage device.? In reality, first kind energy storage device can be accumulator, and Equations of The Second Kind energy storage device can be super capacitor or fly Wheel battery.

Preferably, the service data of the described TRT monitoring real-time acquisition TRT 12 of mould 113 pieces, and Storage data.

Preferably, described TRT monitoring module 113, TRT stator leakage reactance, TRT can be obtained Rotor leakage reactance, TRT excitation leakage reactance, TRT stator resistance, generating unit rotor resistance, pass through TRT parameter, builds TRT mathematical model, does early-stage preparations for computed losses, and obtains storage The internal each several part physical parameter of energy electricity generation system, builds the topological model of whole energy-storing and power-generating system.

TRT monitoring module 113, SVG monitoring module 115 and the data acquisition of load monitoring module 114 Within frequency is 10s-60s, screens extracting data, reject and shut down or there are fault TRT data, Middle control module utilizes real time data, sets up energy-storing and power-generating system regulation-control model, power collection generator phase voltage, TRT phase current, TRT active power, TRT reactive power, reactive-load compensation equipment power, After retaining valid data, enter the hind computation stage.

Preferably, this energy-storing and power-generating system 10 carries out imaginary power automatic compensation in the following way:

By TRT monitoring module, obtain TRT running status, wattful power in energy-storing and power-generating system Rate value, the real time data of energy storage device of energy-storing and power-generating system, extract data and go forward side by side row filter, reject and shut down Or there are fault TRT data；Based on real time data, set up energy-storing and power-generating system reactive Voltage Optimum control Simulation；The energy-storing and power-generating system grid-connected point voltage instruction that parallel control module is assigned according to dispatching patcher, if Superior system does not assign instruction, then by the given instruction of middle control module；Change with the time scale of reactive power Select two kinds of control models；

If idle change yardstick changes with minute/hour level time scale, TRT control mode is converted to Constant active power controller, with energy-storing and power-generating system economical operation for controlling target, sets up object function, will Fetched data substitutes in model, carries out TRT without the distribution of work；

Solve object function, obtain TRT Reactive-power control value；According to also site real-time voltage, design pipe Reason flow process, is divided into five grades by the voltage in adjustable extent, the corresponding different Reactive-power control amount of each grade, According to the running status that each TRT is different, the reactive power value obtained is assigned to the generating dress of correspondence Put；

If idle change yardstick is with millisecond/second level time scale change, TRT operational mode is switched to perseverance Determine voltage control mode；With suppression voltage pulsation as target, set up object function, fetched data is substituted into In model, carry out TRT without the distribution of work；

In energy-storing and power-generating system, each unit receives Reactive power control instruction, completes to refer to according to self corresponding situation Order, after performing instruction, feeds back to dispatching patcher by response value and grid-connected point voltage.

Seeing accompanying drawing 2, the operation method of the energy-storing and power-generating system of the present invention comprises the steps:

S1. TRT monitoring module obtains TRT service data in real time, and stores data, obtains in real time Load power demand situation in energy-storing and power-generating system, obtains the power attenuation situation of energy storage device in real time；

S2. according to load power demand situation, energy storage device in TRT service data, energy-storing and power-generating system Power attenuation situation, be predicted the TRT output in following predetermined instant is meritorious and idle；

S3. gather grid-connected point voltage information, determine that energy-storing and power-generating system is gained merit according to bulk power grid dispatch command simultaneously And idle output demand；

S4. bearing power in meritorious and idle for energy-storing and power-generating system output demand, current energy-storing and power-generating system is needed Ask, TRT is exportable meritorious and idle, exportable idle, the power attenuation of energy storage device of SVG equipment Situation is as constraints, it is achieved the idle work optimization of energy-storing and power-generating system runs, and suppresses voltage pulsation.

Preferably, in step s 2, before accessing bulk power system, TRT monitoring module obtains energy storage Electricity generation system ingredient basic data, the most quantitative in Theoretical Calculation object function；Join based on TRT Number, builds TRT mathematical model, does early-stage preparations for calculating TRT loss, obtains storage further The internal each several part physical parameter of energy electricity generation system, builds whole energy-storing and power-generating system mathematical model.

Preferably, in step s 4, idle work optimization runs and specifically includes following steps:

S41. by TRT monitoring module, obtain TRT running status in energy-storing and power-generating system, gain merit Performance number, the real time data of energy storage device of energy-storing and power-generating system, energy-storing and power-generating system data acquisition during this Integrate frequency range as 10s-60s, extract data and go forward side by side row filter, reject and shut down or there is fault TRT number According to；Based on real time data, set up energy-storing and power-generating system reactive power and voltage control model；Parallel control module The energy-storing and power-generating system grid-connected point voltage instruction assigned according to dispatching patcher, if superior system does not assign instruction, Then by the given instruction of middle control module；Change with the time scale of reactive power and select two kinds of control models；

If the most idle change yardstick changes with minute/hour level time scale, TRT control mode is turned It is changed to constant active power controller, with energy-storing and power-generating system economical operation for controlling target, sets up object function, S1 and S41 fetched data is substituted in model, carries out TRT without the distribution of work；

S43. solve object function, obtain TRT Reactive-power control value；According to also site real-time voltage, design Management process, is divided into five grades by the voltage in adjustable extent, the corresponding different Reactive-power control of each grade Amount, according to the running status that each TRT is different, is assigned to sending out of correspondence by the reactive power value obtained Electric installation；

If the most idle change yardstick is with millisecond/second level time scale change, TRT operational mode is switched For constant voltage control mode；With suppression voltage pulsation as target, set up object function, by S1 and S31 institute Obtain data to substitute in model, carry out TRT without the distribution of work；

S45. in energy-storing and power-generating system, each unit receives Reactive power control instruction, completes according to self corresponding situation Instruction, after performing instruction, feeds back to dispatching patcher by response value and grid-connected point voltage.

Preferably, by supervising device in S41, obtain energy-storing and power-generating system real time data and PCC point voltage Control instruction, arranges PCC point voltage fluctuation threshold values；

Δ U=| U_WFcmd-U_WFout|≤ξ

In formula, U_WFcmdFor energy-storing and power-generating system site desired voltage values；U_WFoutFor energy-storing and power-generating system also Site real-time voltage value；ξ is energy-storing and power-generating system voltage threshold；Δ U is grid-connected point voltage deviation value.

Preferably, in S42, set up the idle work optimization function being assigned as target with energy-storing and power-generating system economic optimization:

Min (F)=w₁P_loss+w₂Q_C+λ₁ΔU_i+λ₂ΔQ

In formula, P_lossFor energy-storing and power-generating system active loss；Q_CFor SVG equipment investment capacity；ΔU_iFor respectively Node voltage gets over limit value；ΔQ_iSend reactive power for TRT and get over limit value；w₁And w₂For active power loss and The weight factor of reactive compensation capacity, and w₁+w₂=1；λ is penalty factor, is calculating optimal function, is rising To restricted problem.

Preferably, S42 is analyzed calculate, first carries out calculating energy-storing and power-generating system Load flow calculation；According to Energy-storing and power-generating system reactive power dimensional variation in time, determines TRT control model, in second/hour level Time, TRT control mode is converted to power limitation control, calculates TRT to reduce network loss as mesh Idle adjustable nargin under Biao, it is ensured that bound for objective function；Set up energy-storing and power-generating system economical operation For the idle control mathematical model of target, by S1 and S41 the data obtained, substitute in model；

The copper loss of the loss of TRT predominantly TRT, its expression formula is:

$P_{cu}=R_s(I_{sq}^2+I_{sd}^2)+R_r(I_{rd}^2+I_{rq}^2)$

In formula, R_sFor generator unit stator resistance, R_rFor generator amature resistance, I_sFor stator current, I_rFor turning Electron current；

In transmission of electricity energy-storing and power-generating system, load is represented by ∏ shape equivalent circuit, load in series in energy-storing and power-generating system Active loss be directly proportional to the current squaring passed through to reactive loss, it may be assumed that

${\mathrm{\ΔP}}_L=\frac{P_1^2+Q_1^2}{U_1^2}R$

${\mathrm{\ΔQ}}_L=\frac{P_1^2+Q_1^2}{U_1^2}X$

U₂For PCC junction point voltage in energy-storing and power-generating system, load in one section of transmission energy-storing and power-generating system Afterwards with bulk power grid before step voltage U₁It is connected；Voltage U₂Active power and the reactive power injected with access point have Close；When fluctuation occurs in wind speed, stablizing of system PCC point busbar voltage can be affected, due to busbar voltage Fluctuation, can increase the network loss of energy-storing and power-generating system, cause economic loss, when fluctuation is more than 10%, and can be to storage The output of energy electricity generation system produces impact, so needing the reactive power of PCC point is regulated and controled, from And maintain U₂Constant；

Under stable situation, energy-storing and power-generating system is incorporated into the power networks, and now energy-storing and power-generating system carries for accessing bulk power grid For electric energy, using unity power factor control, whole energy-storing and power-generating system does not exchanges reactive power with electrical network； Power system voltage regulating depends on TRT, energy storage device and electrical network parameter etc., is determined by reactive requirement, Regulate its stator voltage, with rotor current；

For the purpose of electricity generation system active loss, set up object function:

P_loss=P₁+P₂+P₃

$P_1=\underset{i=1}{\overset{n}{\Σ}}{P}_{cui}$

$P_2=\left\{\underset{i=1}{\overset{n}{\Σ}}\frac{(P_{mi}^2+Q_{mi}^2)(R_{Ti}+R_{Li})}{U_i^2}\right\}$

P₃=P_LT

In formula, P_mi, Q_miIt is respectively i-th doubly-fed generation device and injects meritorious, the idle injection rate of bus bar side； U is that case becomes high side bus voltage；R_Ti, R_LiIt is respectively conversion and becomes on high-tension side resistance and current collection energy storage to case Load resistance in electricity generation system；P₁For TRT copper loss；P₂For load loss in energy-storing and power-generating system；P₃ The active loss of energy storage device.

Preferably, with energy-storing and power-generating system loss minimization as principle, it is contemplated that every TRT active loss, TRT active loss is mainly stator and rotor copper loss, and wherein stator current is:

$I_{si}^2=\frac{\sqrt{({P_i}^2+{Q_i}^2)}}{3U_i}$

Rotor current is:

$I_{ri}=\frac{1}{X_{mi}}\sqrt{\[I_{si}^2(R_{si}^2+X_{li}^2)+U_i^2+2U_i(\frac{P_i{R}_{si}}{3U_i}-\frac{Q_i{X}_{li}}{3U_i})\]}$

$P_{cui}=3I_{si}^2{R}_{si}+3I_{ri}^2{R}_{ri}$

By P_cuiIt is organized into about Q_iOne-place 2-th Order expression formula

$P_{cui}={\mathrm{aQ}}_i^2+{\mathrm{bQ}}_i+c$

$\left\{\begin{array}{c}a=\frac{X_{mi}^2{R}_{si}+R_{si}^2{R}_{ri}+X_{li}^2{R}_{ri}}{3U_i^2{X}_{mi}^2}\\ b=\frac{2X_{li}{R}_{ri}}{X_{mi}^2}\\ c=\frac{(R_{si}{X}_{mi}^2+R_{si}^2{R}_{ri}+X_{li}^2{R}_{ri})P_i^2+6R_{si}{R}_{ri}{U}_i^2{P}_i+9R_{ri}{U}_i^4}{3X_{mi}^2{U}_i^2}\end{array}\right.$

In formula, U_iIt it is the stator terminal voltage of i-th TRT；X_1i=X_si+X_mi, X_2i=X_ri+X_mi, its In, X_si、X_m、X_riIt is respectively the stator leakage reactance of i-th TRT, excitation leakage reactance and rotor leakage reactance；

In energy-storing and power-generating system, the active loss reactive loss in load is expressed as:

$P_{Li}=Q_{Li}\frac{R_i}{X_i}$

In formula, Q_LiFor connecting bus in energy-storing and power-generating system to TRT line concentration and the idle damage of energy storage device Consumption value；

The active loss reactive loss of energy storage device is indicated:

$P_{LT}=P_0+P_k(\frac{100Q_{LT}}{S_N{U}_k\%}-\frac{I_O\%}{U_k\%})$

To sum up, bear in TRT, energy storage device, energy-storing and power-generating system in proposition comprises energy-storing and power-generating system It is loaded in the object function that interior active power loss is minimum:

Min (F)=w₁P_loss+w₂Q_C+λ₁ΔU_i+λ₂ΔQ

In formula, P_lossFor energy-storing and power-generating system active loss；Q_CFor SVG equipment investment capacity；ΔU_iFor respectively Node voltage gets over limit value；ΔQ_iSend reactive power for TRT and get over limit value；w₁And w₂For active power loss and The weight factor of reactive compensation capacity, and w₁+w₂=1；With for penalty factor.

Preferably, wherein the trend constraints of Optimized model is:

$P_i=U_i\underset{j=1}{\overset{n}{\Σ}}{U}_j(G_{ij}{\mathrm{cos\θ}}_{ij}+B_{ij}{\mathrm{sin\θ}}_{ij})$

$Q_i=U_i\underset{j=1}{\overset{n}{\Σ}}{U}_j(G_{ij}{\mathrm{cos\θ}}_{ij}-B_{ij}{\mathrm{sin\θ}}_{ij})$

Idle equality constraint is

$\underset{i=1}{\overset{n}{\Σ}}(Q_{mi}-{\mathrm{\ΔQ}}_i)-Q_{LT}=Q_{ref}$

Inequality constraints

$0\≤P_i\≤P_{i\max }^{ref}$

Q_imin≤Q_i≤Q_imax

V_i ^ref-V_i ^err≤V_i≤V_i ^ref+V_i ^err

In formula,It is that i-th TRT maximum predicted sends power, Q_imaxIdle for TRT maximum Output valve, Q_iminFor the minimum idle output valve of TRT, V_i ^errFor node voltage fluctuation range.

Preferably, in step S43, grid-connected point voltage perunit value is divided into different brackets, respectively U_a、 U_b、U₀、U_c、U_d, using different grades of busbar voltage as amplitude limit, whole control process is managed, Ensure, during reducing network loss, to take into account busbar voltage quality；Make U₀=1, i.e. occur without under abnormal conditions Busbar voltage, makes U_b、U_cIt is respectively U₀± 5%, make U_a、U_dIt is respectively U₀± 10%；

(1) U is worked as₂When being in voltage magnitude bottom half；

1)U₂≤U_aTime, PCC point voltage reaches the lower limit that fluctuates, and needs energy-storing and power-generating system to provide reactive power, Improving voltage, TRT control mode is converted to constant voltage control；

2)U_a≤U₂≤U_bTime, it is desirable to provide reactive power reduces energy-storing and power-generating system network loss, but still needs to nothing Merit power assurance voltage, TRT is idle is output as in now regulation

$Q=\frac{2U_b-U_2}{U_b}{Q}_{mi}$

3)U_b≤U₂≤U₀Time, this interval busbar voltage grade meets demand, and TRT provides reactive power Reducing network loss, TRT is idle is output as in now regulation

Q=Q_m

(2) U is worked as₂When being in voltage magnitude upper half, regulation process is similar with flow process (1).

Preferably, in described step S44, set up the idle work optimization function of suppression multiple target voltage pulsation

$Q_{ref}=K_{ref}^U(U_{mea}-U_{ref})+\underset{0}{\overset{T_{ref}^U}{\∫}}(U_{mea}-U_{ref})dt+K_{RX}\[\frac{\underset{0}{\overset{T_{\mathrm{int}}}{\∫}}(P_{avg}-P_{mea})dt}{T_{\mathrm{int}}}\]$

In formula, U_meaFor also site actual measurement voltage, U_refFor voltage reference value,For Control of Voltage gain system Number,For voltage error integration time constant, K_RXFor reactive power compensation gain coefficient, T_intDuring for controlling Between yardstick.

First according to voltage measured value and voltage reference value, according to TRT constant voltage control mode, calculate Under constant voltage control mode, the reactive requirement value of whole field；It is simultaneously introduced voltage pulsation inhibition function, obtains The idle reference value of suppression voltage pulsation, obtains final reactive requirement value, according to energy-storing and power-generating system SCADA Data, when TRT carries out reactive power distribution, need to take into full account going out in real time of each TRT Power situation, operation conditions, could utilize algorithm that TRT is carried out different process.

When TRT is classified by the present invention, mainly account at two aspects, be first TRT Operation conditions, in the assignment procedure, it should first the TRT that operation conditions is bad is paid the utmost attention to；Its Secondary consideration wind speed and wind power prediction result, according to the running status between energy-storing and power-generating system TRT, TRT is divided three classes.The first kind is next period shut-down TRT；Equations of The Second Kind is that TRT is adjusted The TRT that the energy-conservation force rate previous control cycle is strong, the 3rd class is that TRT regulating power ratio is previous The TRT that the control cycle is weak.The allocation strategy of TRT is as follows.

$\underset{i=1}{\overset{n}{\Σ}}{Q}_i=Q_{ref}+Q_{loss}$

In formula, Q_refFor suppression voltage pulsation calculated energy-storing and power-generating system reactive requirement；Q_lossFor energy storage Electricity generation system reactive loss.

Q_i1=0

$Q_{i2}=({\mathrm{\ΣQ}}_{i2,t+1}-{\mathrm{\ΣQ}}_{i2,t})\frac{Q_{i2,t}}{{\mathrm{\ΣQ}}_{i2,t+1}}+Q_{i2,t}$

$Q_{i3}=({\mathrm{\ΣQ}}_{i3,t}-{\mathrm{\ΣQ}}_{i3,t+1})\frac{Q_{i3,t+1}}{{\mathrm{\ΣQ}}_{i3,t}}+Q_{i3,t+1}$

$Q_{i4}=\frac{Q_{i4,t+1}}{{\mathrm{\ΣQ}}_{i4,t}}+Q_{i4,t+1}$

In formula, Q_ixFor the idle output valve of i-th TRT of xth class, Q_ix,tIdle defeated for current period Go out value, Q_ix,t+1Idle output valve for next cycle.

Above content is to combine concrete preferred implementation further description made for the present invention, no Can assert the present invention be embodied as be confined to these explanations.Common for the technical field of the invention For technical staff, without departing from the inventive concept of the premise, make some equivalents and substitute or obvious modification, And performance or purposes are identical, protection scope of the present invention all should be considered as belonging to.

Claims (10)

1. an operation method for energy-storing and power-generating system, the method comprises the steps:

S1. TRT monitoring module obtains TRT service data in real time, and stores data, obtains in real time Load power demand situation in energy-storing and power-generating system, obtains the power attenuation situation of energy storage device in real time；

S2. according to load power demand situation, energy storage device in TRT service data, energy-storing and power-generating system Power attenuation situation, be predicted the TRT output in following predetermined instant is meritorious and idle；

S3. gather grid-connected point voltage information, determine that energy-storing and power-generating system is gained merit according to bulk power grid dispatch command simultaneously And idle output demand；

S4. bearing power in meritorious and idle for energy-storing and power-generating system output demand, current energy-storing and power-generating system is needed Ask, TRT is exportable meritorious and idle, exportable idle, the power attenuation of energy storage device of SVG equipment Situation is as constraints, it is achieved the idle work optimization of energy-storing and power-generating system runs, and suppresses voltage pulsation.

2. the method for claim 1, it is characterised in that in step s 2, is accessing bulk power grid system Before system, TRT monitoring module obtains energy-storing and power-generating system ingredient basic data, Theoretical Calculation target In function the most quantitative；Based on TRT parameter, build TRT mathematical model, for calculating generating dress Put loss and do early-stage preparations, obtain the internal each several part physical parameter of energy-storing and power-generating system further, build whole Energy-storing and power-generating system mathematical model.

3. method as claimed in claim 2, it is characterised in that in step s 4, idle work optimization runs tool Body comprises the steps:

S41. by TRT monitoring module, obtain TRT running status in energy-storing and power-generating system, gain merit Performance number, the real time data of energy storage device of energy-storing and power-generating system, energy-storing and power-generating system data acquisition during this Integrate frequency range as 10s-60s, extract data and go forward side by side row filter, reject and shut down or there is fault TRT number According to；Based on real time data, set up energy-storing and power-generating system reactive power and voltage control model；Parallel control module The energy-storing and power-generating system grid-connected point voltage instruction assigned according to dispatching patcher, if superior system does not assign instruction, Then by the given instruction of middle control module；Change with the time scale of reactive power and select two kinds of control models；

If the most idle change yardstick changes with minute/hour level time scale, TRT control mode is turned It is changed to constant active power controller, with energy-storing and power-generating system economical operation for controlling target, sets up object function, S1 and S41 fetched data is substituted in model, carries out TRT without the distribution of work；

S43. solve object function, obtain TRT Reactive-power control value；According to also site real-time voltage, design Management process, is divided into five grades by the voltage in adjustable extent, the corresponding different Reactive-power control of each grade Amount, according to the running status that each TRT is different, is assigned to sending out of correspondence by the reactive power value obtained Electric installation；

If the most idle change yardstick is with millisecond/second level time scale change, TRT operational mode is switched For constant voltage control mode；With suppression voltage pulsation as target, set up object function, by S1 and S31 institute Obtain data to substitute in model, carry out TRT without the distribution of work；

S45. in energy-storing and power-generating system, each unit receives Reactive power control instruction, completes according to self corresponding situation Instruction, after performing instruction, feeds back to dispatching patcher by response value and grid-connected point voltage.

4. method as claimed in claim 3, it is characterised in that by supervising device in S41, obtain energy storage Electricity generation system real time data and PCC point voltage control instruction, arrange PCC point voltage fluctuation threshold values；

Δ U=| U_WFcmd-U_WFout|≤ξ

In formula, U_WFcmdFor energy-storing and power-generating system site desired voltage values；U_WFoutFor energy-storing and power-generating system also Site real-time voltage value；ξ is energy-storing and power-generating system voltage threshold；Δ U is grid-connected point voltage deviation value.

5. method as claimed in claim 4, it is characterised in that in S42, set up with energy-storing and power-generating system warp Ji optimized distribution is the idle work optimization function of target:

Min (F)=w₁P_loss+w₂Q_C+λ₁ΔU_i+λ₂ΔQ

In formula, P_lossFor energy-storing and power-generating system active loss；Q_CFor SVG equipment investment capacity；ΔU_iFor respectively Node voltage gets over limit value；ΔQ_iSend reactive power for TRT and get over limit value；w₁And w₂For active power loss and The weight factor of reactive compensation capacity, and w₁+w₂=1；λ is penalty factor, is calculating optimal function, is rising To restricted problem.

6. method as claimed in claim 5, it is characterised in that be analyzed in S42 calculating, first carry out Calculate energy-storing and power-generating system Load flow calculation；According to energy-storing and power-generating system reactive power dimensional variation in time, really Determine TRT control model, when second/hour level, TRT control mode be converted to power limitation control, Calculate the TRT idle adjustable nargin under with reduction network loss as target, it is ensured that the constraint bar of object function Part；Set up the idle control mathematical model that energy-storing and power-generating system economical operation is target, by S1 and S41 institute Obtain data, substitute in model；

The copper loss of the loss of TRT predominantly TRT, its expression formula is:

$P_{cu}=R_s(I_{sq}^2+I_{sd}^2)+R_r(I_{rd}^2+I_{rq}^2)$

In formula, R_sFor generator unit stator resistance, R_rFor generator amature resistance, I_sFor stator current, I_rFor turning Electron current；

In transmission of electricity energy-storing and power-generating system, load is represented by ∏ shape equivalent circuit, load in series in energy-storing and power-generating system Active loss be directly proportional to the current squaring passed through to reactive loss, it may be assumed that

${\mathrm{\ΔP}}_L=\frac{P_1^2+Q_1^2}{U_1^2}R$

${\mathrm{\ΔQ}}_L=\frac{P_1^2+Q_1^2}{U_1^2}X$

U₂For PCC junction point voltage in energy-storing and power-generating system, load in one section of transmission energy-storing and power-generating system Afterwards with bulk power grid before step voltage U₁It is connected；Voltage U₂Active power and the reactive power injected with access point have Close；When fluctuation occurs in wind speed, stablizing of system PCC point busbar voltage can be affected, due to busbar voltage Fluctuation, can increase the network loss of energy-storing and power-generating system, cause economic loss, when fluctuation is more than 10%, and can be to storage The output of energy electricity generation system produces impact, so needing the reactive power of PCC point is regulated and controled, from And maintain U₂Constant；

Under stable situation, energy-storing and power-generating system is incorporated into the power networks, and now energy-storing and power-generating system carries for accessing bulk power grid For electric energy, using unity power factor control, whole energy-storing and power-generating system does not exchanges reactive power with electrical network； Power system voltage regulating depends on TRT, energy storage device and electrical network parameter etc., is determined by reactive requirement, Regulate its stator voltage, with rotor current；

For the purpose of electricity generation system active loss, set up object function:

P_loss=P₁+P₂+P₃

$P_1=\underset{i=1}{\overset{n}{\Σ}}{P}_{cui}$

$P_2=\left\{\underset{i=1}{\overset{n}{\Σ}}\frac{(P_{mi}^2+Q_{mi}^2)(R_{Ti}+R_{Li})}{U_i^2}\right\}$

P₃=P_LT

In formula, P_mi, Q_miIt is respectively i-th doubly-fed generation device and injects meritorious, the idle injection rate of bus bar side； U is that case becomes high side bus voltage；R_Ti, R_LiIt is respectively conversion and becomes on high-tension side resistance and current collection energy storage to case Load resistance in electricity generation system；P₁For TRT copper loss；P₂For load loss in energy-storing and power-generating system；P₃ The active loss of energy storage device.

7. method as claimed in claim 6, it is characterised in that with energy-storing and power-generating system loss minimization as principle, In view of every TRT active loss, TRT active loss is mainly stator and rotor copper loss, wherein Stator current is:

$I_{si}^2=\frac{\sqrt{({P_i}^2+{Q_i}^2)}}{3U_i}$

Rotor current is:

$I_{ri}=\frac{1}{X_{mi}}\sqrt{\[I_{si}^2(R_{si}^2+X_{li}^2)+U_i^2+2U_i(\frac{P_i{R}_{si}}{3U_i}-\frac{Q_i{X}_{li}}{3U_i})\]}$

$P_{cui}=3I_{si}^2{R}_{si}+3I_{ri}^2{R}_{ri}$

By P_cuiIt is organized into about Q_iOne-place 2-th Order expression formula

$P_{cui}={\mathrm{aQ}}_i^2+{\mathrm{bQ}}_i+c$

$\left\{\begin{array}{c}a=\frac{X_{mi}^2{R}_{si}+R_{si}^2{R}_{ri}+X_{li}^2{R}_{ri}}{3U_i^2{X}_{mi}^2}\\ b=\frac{2X_{li}{R}_{ri}}{X_{mi}^2}\\ c=\frac{(R_{si}{X}_{mi}^2+R_{si}^2{R}_{ri}+X_{li}^2{R}_{ri})P_i^2+6R_{si}{R}_{ri}{U}_i^2{P}_i+9R_{ri}{U}_i^4}{3X_{mi}^2{U}_i^2}\end{array}\right.$

In formula, U_iIt it is the stator terminal voltage of i-th TRT；X_1i=X_si+X_mi, X_2i=X_ri+X_mi, its In, X_si、X_m、X_riIt is respectively the stator leakage reactance of i-th TRT, excitation leakage reactance and rotor leakage reactance；

In energy-storing and power-generating system, the active loss reactive loss in load is expressed as:

$P_{Li}=Q_{Li}\frac{R_i}{X_i}$

In formula, Q_LiFor connecting bus in energy-storing and power-generating system to TRT line concentration and the idle damage of energy storage device Consumption value；

The active loss reactive loss of energy storage device is indicated:

$P_{LT}=P_0+P_k(\frac{100Q_{LT}}{S_N{U}_k\%}-\frac{I_O\%}{U_k\%})$

To sum up, bear in TRT, energy storage device, energy-storing and power-generating system in proposition comprises energy-storing and power-generating system It is loaded in the object function that interior active power loss is minimum:

Min (F)=w₁P_loss+w₂Q_C+λ₁ΔU_i+λ₂ΔQ

In formula, P_lossFor energy-storing and power-generating system active loss；Q_CFor SVG equipment investment capacity；ΔU_iFor respectively Node voltage gets over limit value；ΔQ_iSend reactive power for TRT and get over limit value；w₁And w₂For active power loss and The weight factor of reactive compensation capacity, and w₁+w₂=1；With for penalty factor.

8. method as claimed in claim 7, it is characterised in that, the wherein trend constraints of Optimized model For:

$P_i=U_i\underset{j=1}{\overset{n}{\Σ}}{U}_j(G_{ij}{\mathrm{cos\θ}}_{ij}+B_{ij}{\mathrm{sin\θ}}_{ij})$

$Q_i=U_i\underset{j=1}{\overset{n}{\Σ}}{U}_j(G_{ij}{\mathrm{cos\θ}}_{ij}-B_{ij}{\mathrm{sin\θ}}_{ij})$

Idle equality constraint is

$\underset{i=1}{\overset{n}{\Σ}}(Q_{mi}-{\mathrm{\ΔQ}}_i)-Q_{LT}=Q_{ref}$

Inequality constraints

$0\≤P_i\≤P_{imax}^{ref}$

Q_imin≤Q_i≤Q_imax

V_i ^ref-V_i ^err≤V_i≤V_i ^ref+V_i ^err

In formula,It is that i-th TRT maximum predicted sends power, Q_imaxIdle for TRT maximum Output valve, Q_iminFor the minimum idle output valve of TRT, V_i ^errFor node voltage fluctuation range.

9. method as claimed in claim 8, it is characterised in that, in step S43, by grid-connected point voltage Perunit value is divided into different brackets, respectively U_a、U_b、U₀、U_c、U_d, with different grades of busbar voltage As amplitude limit, whole control process is managed, it is ensured that during reducing network loss, takes into account bus electricity Pressure quality；Make U₀=1, i.e. occur without abnormal conditions Down Highway voltage, make U_b、U_cIt is respectively U₀± 5%, Make U_a、U_dIt is respectively U₀± 10%；

(1) U is worked as₂When being in voltage magnitude bottom half；

1)U₂≤U_aTime, PCC point voltage reaches the lower limit that fluctuates, and needs energy-storing and power-generating system to provide reactive power, Improving voltage, TRT control mode is converted to constant voltage control；

2)U_a≤U₂≤U_bTime, it is desirable to provide reactive power reduces energy-storing and power-generating system network loss, but still needs to nothing Merit power assurance voltage, TRT is idle is output as in now regulation

$Q=\frac{2U_b-U_2}{U_b}{Q}_{mi}$

3)U_b≤U₂≤U₀Time, this interval busbar voltage grade meets demand, and TRT provides reactive power Reducing network loss, TRT is idle is output as in now regulation

Q=Q_m

(2) U is worked as₂When being in voltage magnitude upper half, regulation process is similar with flow process (1).

10. method as claimed in claim 9, it is characterised in that, in described step S44, set up The idle work optimization function of suppression multiple target voltage pulsation

$Q_{ref}=K_{ref}^U(U_{mea}-U_{ref})+\underset{0}{\overset{T_{ref}^U}{\∫}}(U_{mea}-U_{ref})dt+K_{RX}\[\frac{\underset{0}{\overset{T_{\mathrm{int}}}{\∫}}(P_{avg}-P_{mea})dt}{T_{\mathrm{int}}}\]$

In formula, U_meaFor also site actual measurement voltage, U_refFor voltage reference value,For Control of Voltage gain system Number,For voltage error integration time constant, K_RXFor reactive power compensation gain coefficient, T_intDuring for controlling Between yardstick.