CN103996149A - Method for analyzing wind power layout of regional power grid based on quiescent voltage stability - Google Patents

Abstract

The invention provides a method for analyzing wind power layout of a regional power grid based on quiescent voltage stability. The method comprises the steps of setting up a wind power access reactive characteristic model on a network model of the regional power grid; acquiring PV curves of wind power access substation buses in a normal operation mode and a N-1 operation mode; acquiring critical voltages of the wind power access substation buses according to the PV curves; acquiring normal voltages of the buses; respectively acquiring accessible wind power capacity in the normal operation mode and the N-1 operation mode, acquiring theoretical acceptance wind power capacity of the substation buses, acquiring an acceptance ability ratio of wind power in the regional power grid, and acquiring wind power layout of each bus in the regional power grid according to the acceptance ability ratio and wind power access total quantity of the regional power grid. A relative ratio of the access capacity of the substation to the access capacity of other substations is judged by means of limit wind power access capacity of the substation buses, and then the access capacity of the substations is allocated under the given planning capacity.

Description

A kind of regional power grid wind-powered electricity generation topological analysis method based on static electric voltage stability

Technical field

The present invention relates to the method for a kind of electric system regional power grid wind-powered electricity generation layout research, be specifically related to a kind of regional power grid wind-powered electricity generation topological analysis method based on static electric voltage stability.

Background technology

In recent years, Wind Power Generation Industry development is swift and violent.Yet wind-powered electricity generation off-grid accident also occurs again and again, has highlighted wind farm grid-connected shortage of standard and technological lag.

The system scale of the installed capacity of wind-driven power that electrical network can bear and place electrical network, power supply architecture and distribution, part throttle characteristics etc. are closely related.After the extensive development of wind-powered electricity generation, must participate in systematic electricity balance, when large-scale wind power simultaneity factor is higher, the variation that wind-powered electricity generation is exerted oneself will cause great impact to electrical network, system need to leave the fluctuation that enough margin capacities are carried out balance wind-powered electricity generation, to guarantee the safe and stable operation of electrical network.Therefore, for grid structure, the fixing regional power grid of power supply architecture, the receiving ability of wind-powered electricity generation has certain limit, and it is unscientific blindly accessing wind-powered electricity generation.

In prior art, wind-powered electricity generation topological analysis method, except considering the each side factors such as wind-resources and economic planning, has considered the impact of wind-powered electricity generation access on the stabilization of power grids limit more.

But the power of rack itself is also the pacing factor that determines that can system after wind-electricity integration stable operation, is not but considered.As in wind-powered electricity generation allocation plan, consider more the strong and weak characteristic of rack itself, the impact of the wind-powered electricity generation of assessment area electrical network access on rack more effectively.

Summary of the invention

In order to overcome the defect of above-mentioned prior art, the invention provides a kind of regional power grid wind-powered electricity generation topological analysis method based on static electric voltage stability.

In order to realize foregoing invention object, the present invention takes following technical scheme:

A regional power grid wind-powered electricity generation topological analysis method based on static electric voltage stability, its improvements are: said method comprising the steps of:

I, on the network model of regional power grid, build wind-powered electricity generation and access idle characteristic model;

II, obtain the PV curve of the access of wind-powered electricity generation under normal operating mode and N-1 method of operation substation bus bar;

III, according to described PV curve, obtain the critical voltage of wind-powered electricity generation access substation bus bar;

IV, according to the static stability reserve coefficient of described critical voltage and system, obtain the normal voltage of described bus;

V, obtain wind-powered electricity generation capacity accessible under normal operating mode and the N-1 method of operation respectively, the theory that obtains substation bus bar is received wind-powered electricity generation capacity;

In VI, acquisition regional power grid, wind-powered electricity generation is received energy force rate, accesses total amount obtain each bus wind-powered electricity generation layout in regional power grid by described receiving energy force rate and regional power grid wind-powered electricity generation;

VII, the stability of respectively each bus access being calculated after gained wind-powered electricity generation are carried out verification.

Further, in described step I, all wind-powered electricity generations in wind-powered electricity generation base are considered as to unit power supply, wind-powered electricity generation is exerted oneself after primary substation boosts by equivalent circuit access Infinite bus system;

Determine wind-powered electricity generation on-position, on the network model of regional power grid, build wind-powered electricity generation and access idle characteristic model.

Further, in described Step II I, the PV curve that uses PV curve static voltage stability analysis method to obtain is determined the critical voltage of wind-powered electricity generation access substation bus bar.

Further, in described step IV, the increase of exerting oneself of wind-powered electricity generation on substation bus bar, voltage reduces gradually, according to the critical point voltage of described substation bus bar and static stability reserve coefficient, obtains respectively under normal operating mode and the N-1 method of operation operating point voltage as shown in the formula (1):

K _v＝(U _z-U _c)/U _Z×100％ (1)

Wherein, K _vfor static stability reserve coefficient, U _cfor the critical voltage of substation bus bar, U _zoperating point voltage for substation bus bar.

Further, in described step V, comprise the following steps:

S501, corresponding the exerting oneself as the theory receiving wind-powered electricity generation capacity P of substation bus bar of the operating point of determining normal voltage according to described PV curve _i;

S502, the theory that obtains respectively single substation bus bar i under normal operating mode and the N-1 method of operation are received wind-powered electricity generation capacity P _iand P _{i (N-1)};

S603, the theory of determining single substation bus bar i under described normal operating mode and the N-1 method of operation receive wind-powered electricity generation capacity as shown in the formula (2):

P _ii＝min(P _i,P _i(N-1)) (2)

In formula, P _ifor the theory of single substation bus bar i under normal operating mode is received wind-powered electricity generation capacity, P _{i (N-1)}for the theory of single substation bus bar i under the N-1 method of operation is received wind-powered electricity generation capacity.

Further, described step VI comprises the following steps:

S601, determine that substation bus bar i wind-powered electricity generation in regional power grid receives ability such as following formula (3):

$K=P_{\mathrm{ii}}/\underset{i=1}{\mathrm{\Σ}}{P}_{\mathrm{ii}}---\left(3\right);$

In formula, P _iifor the theory of single substation bus bar i under normal operating mode and the N-1 method of operation is received wind-powered electricity generation capacity;

In S602, definite area electrical network, each bus wind-powered electricity generation layout is as shown in the formula (4):

P _iw＝K·P _w (4)

In formula, P _wfor regional power grid wind-powered electricity generation access total amount.

Further, in described step VII, respectively the stability after each bus access calculating gained wind-powered electricity generation is carried out to verification and comprises:

Judge whether electrical network can meet transient stability, if meet, calculate and finish; If do not meet, adjust static stability reserve coefficient K _vif, K _vduring %=20%, still do not meet stability verification, judge that this bus cannot access wind-powered electricity generation, wind-powered electricity generation that this bus distributes proportionally accesses other bus.

Compared with prior art, excellent effect of the present invention is:

1, the regional power grid wind-powered electricity generation topological analysis method of method of the present invention based on existing P-V curve static voltage stability analysis method, can be wind-powered electricity generation layout technology access capacity recommendation is provided, the impact of the wind-powered electricity generation of assessment area electrical network access on rack more effectively.

2, method of the present invention is carried out the analysis and research of wind-powered electricity generation installation layout based on Power grid structure, utilize the limit wind-powered electricity generation access capacity of substation bus bar, the degree of assessment wind-powered electricity generation access to electric network influencing, and determine accordingly the ratio of regional Wind Power Generation scale, thereby provide rational Wind Power Generation layout suggestion.

3, method of the present invention is in wind-powered electricity generation allocation plan, except the stability analysis of electrical network, considered more the strong and weak characteristic of rack itself, the impact of the wind-powered electricity generation of assessment area electrical network access on rack more effectively, has guaranteed the stable operation of system after wind-electricity integration.

4, method of the present invention is utilized the limit wind-powered electricity generation access capacity of substation bus bar, judges this transformer station's access capacity and relative proportionings other transformer station's access capacities, then for distribute the capacity of each transformer station's access under given planned capacity; Thereby in wind-powered electricity generation allocation plan, considered more the strong and weak characteristic of rack itself, the impact of the wind-powered electricity generation of assessment area electrical network access on rack more effectively.

Accompanying drawing explanation

Fig. 1 is the regional power grid wind-powered electricity generation topological analysis method flow diagram based on static voltage stability reserve factor;

Fig. 2 is network connection figure and the equivalent circuit schematic diagram thereof of wind-powered electricity generation base connecting system;

Fig. 3 is voltage stability margin, i.e. PV curve static stability reserve coefficient schematic diagram;

Fig. 4 is wind-powered electricity generation base connecting system schematic diagram;

Result of calculation schematic diagram under Tu5Wei transformer station 1 normal operating mode;

Result of calculation schematic diagram under Tu6Wei transformer station 1 " N-1 " method of operation.

Embodiment

Below in conjunction with accompanying drawing, the specific embodiment of the present invention is described in further detail.

As shown in Figure 1, Fig. 1 is the regional power grid wind-powered electricity generation topological analysis method flow diagram based on static electric voltage stability; Method of the present invention comprises the following steps:

Step 1, on the network model of regional power grid, build wind-powered electricity generation and access idle characteristic model, determine wind-powered electricity generation on-position;

Step 2, obtain the PV curve of the access of wind-powered electricity generation under normal operating mode and N-1 method of operation substation bus bar;

Step 3, according to described PV curve, obtain the critical voltage of wind-powered electricity generation access substation bus bar;

Step 4, according to the static stability reserve coefficient of described critical voltage and system, obtain the normal voltage of described bus;

Step 5, obtain wind-powered electricity generation capacity accessible under normal operating mode and the N-1 method of operation respectively;

The receiving energy force rate of receiving wind power bus in step 6, acquisition regional power grid, by each bus wind-powered electricity generation layout in described receiving energy force rate and regional power grid wind-powered electricity generation access total amount acquisition regional power grid;

Step 7, the stability of respectively each bus access being calculated after gained wind-powered electricity generation are carried out verification.

In step 1, on the network model of regional power grid, build wind-powered electricity generation and access idle characteristic model, determine wind-powered electricity generation on-position.

All wind-powered electricity generations in wind-powered electricity generation base are considered as to unit power supply, and wind-powered electricity generation is exerted oneself after primary substation boosts by equivalent circuit access Infinite bus system; Determine wind-powered electricity generation on-position, on the network model of regional power grid, build wind-powered electricity generation and access idle characteristic model.

As shown in Figure 2, Fig. 2 is wind-powered electricity generation base connecting system schematic diagram; In embodiments of the invention, a wind-powered electricity generation connecting system is done to following simplification: all wind-powered electricity generations in wind-powered electricity generation base are considered as to a unit power supply, and wind-powered electricity generation is exerted oneself after 750kV collects booster stations and boosts by an equivalent circuit access Infinite bus system.

In Fig. 2 (b) equivalent circuit diagram, Z _t1=R _t1+ jX _t1, Z _t2=R _t2+ jX _t2, Z _t3=R _t3+ jX _t3be respectively 750kV wind-powered electricity generation/photovoltaic and collect the equivalent impedance of boost the high pressure winding, middle pressure winding and the low pressure winding that become;

Y _t=G _t-jB _tfor 750kV wind-powered electricity generation/photovoltaic collects the Equivalent admittance that boosts and become;

Z _l=R _l+ jX _lfor wind-powered electricity generation collects the equivalent impedance of booster stations 750kV outlet.

Because 750kV wind-powered electricity generation/photovoltaic collects boost low pressure side not on-load or reactive power compensator, meritorious all very little with reactive loss, therefore the equivalent circuit of three-phase transformer can be reduced to two phase transformer, as Fig. 2 (c) simplifies as shown in equivalent circuit diagram; Wherein, Z _t=Z _t1+ Z _t2=(R _t1+ R _t2)+j (X _t1+ X _t2).

As shown in Figure 2, wind-powered electricity generation/photovoltaic collects the reactive loss that booster system mainly exists and comprises: wind-powered electricity generation collects the reactive loss Δ Q on the main-transformer of the step-up transformer of standing _t, wind-powered electricity generation collects the Equivalent admittance reactive loss Q of the step-up transformer of standing _yTand wind-powered electricity generation collects the reactive loss Δ Q in the step-up transformer outlet of station _l, and Q _l/ 2 is the charge power of 750kV outlet.

Active loss on main-transformer and reactive loss are determined as shown in the formula (1) (2):

$\begin{array}{c}\mathrm{\Δ}{S}_T=\mathrm{\Δ}{P}_T+\mathrm{\Δ}{Q}_T=\mathrm{\Δ}{\stackrel{\·}{U}}_T{{\stackrel{\·}{I}}_3}^{*}=Z_T{\stackrel{\·}{I}}_3{{\stackrel{\·}{I}}_3}^{*}\\ =[(R_{T1}+R_{T2})+j(X_{T1}+X_{T2})]\frac{P_g+j{Q}_g}{{\stackrel{\·}{U}}_3}{\left(\frac{P_g+j{Q}_g}{{\stackrel{\·}{U}}_3}\right)}^{*}\\ =[(R_{T1}+R_{T2})+j(X_{T1}+X_{T2})]\frac{{P_g}^2+{Q_g}^2}{{U_3}^2}\end{array}---\left(1\right)$

$P_{\mathrm{yT}}+j{Q}_{\mathrm{yT}}={\stackrel{\·}{U}}_2{\left[(G_T-j{B}_T){\stackrel{\·}{U}}_2\right]}^{*}={U_2}^2(G_T+j{B}_T)=G_T{U_2}^2+j{B}_T{U_2}^2---\left(2\right)$

Obtain wind-powered electricity generation and collect the reactive loss Δ Q on main-transformer in booster stations _t, main-transformer Equivalent admittance reactive loss Q _yTshown in (3) (4):

$\mathrm{\Δ}{Q}_T=(X_{T1}+X_{T2})\frac{{P_g}^2+{Q_g}^2}{{U_3}^2}=(X_{T1}+X_{T2})\frac{{P_g}^2}{{U_3}^2}---\left(3\right)$

Q _yT＝B _TU ₂ ² (4)

In above formula, X _t1, X _t2be respectively reactance; P _gfor wind-powered electricity generation is meritorious, exert oneself; U ₃for wind-powered electricity generation collects station low-pressure side bus voltage; B _tsusceptance for transformer; U ₂for wind-powered electricity generation collects station high-voltage side bus voltage; P ₂for being the meritorious trend of circuit; Q ₂for line reactive power; X _lfor line reactance; B _lfor line admittance.

From above formula (3), collect the reactive loss of booster stations main-transformer and wind-powered electricity generation base meritoriously and idle exert oneself, the resistance value of main-transformer medium and high pressure winding has substantial connection.

Due to the reactive-load compensation equipment of each wind energy turbine set/photovoltaic plant in wind-powered electricity generation/photovoltaic base substantially can compensate in and send the reactive loss on line, i.e. the reactive loss Q of wind energy turbine set _g≈ 0; The 330kV busbar voltage of 750kV main transformer is controlled between 1.00pu～1.10pu conventionally, and amplitude of variation is relatively little.Therefore,, when the parameter of transformer is determined, the reactive loss on transformer will depend primarily on meritorious the exerting oneself in wind-powered electricity generation/photovoltaic base.It is larger that wind-powered electricity generation/photovoltaic base meritorious exerted oneself, the reactive loss Δ Q on main-transformer _talso larger.

By formula (4), can be found out, collect the reactive loss Q of the Equivalent admittance on booster stations main-transformer _yTby boosting, become 750kV busbar voltage U ₂determine with the susceptance of transformer.According to the requirement of relevant rules, 750kV busbar voltage is controlled at 1.00pu～1.10pu conventionally, and amplitude of variation is very little.Therefore, Q _yTamplitude of variation is very little.Meanwhile, Q _yTconventionally be far smaller than Δ Q _t, therefore that main concern is the reactive loss Δ Q on main-transformer _t.

Acquisition collects the reactive loss Δ Q in booster stations 750kV outlet _lwith charge power Q _l/ 2 expression formula:

$Q_l/2=\frac{B_l{U_2}^2}{2}---\left(5\right)$

$\mathrm{\Δ}{Q}_l=\frac{{P_2}^2+{Q_2}^2}{{U_2}^2}{X}_l---\left(6\right)$

In formula, P ₂=P _g-Δ P _t, Q ₂=Q _l/ 2-Δ Q _t-Q _yT.

Charge power Q on circuit _l/ 2 depend primarily on the voltage levvl of main-transformer 750kV bus, so under normal operating mode, the charge power amplitude of variation on circuit is less.Reactive loss Δ Q on circuit _ldepend primarily on the meritorious trend P on circuit ₂with reactive power flow Q ₂; Wherein, P ₂mainly be subject to the meritorious P that exerts oneself of wind-powered electricity generation _gimpact; Q ₂depend primarily on the charge power of circuit and the reactive loss on main-transformer, and conventionally much smaller than P ₂.Therefore, wind-powered electricity generation collects the reactive loss Δ Q in booster stations 750kV outlet _laffected by meritorious the exerting oneself of wind-powered electricity generation; Wind-powered electricity generation is meritorious exerts oneself greatlyr, and the reactive loss in 750kV outlet is also larger, and in corresponding net, interdependent node voltage is also lower.

It is the reactive loss Δ Q on main-transformer that 750kV wind-powered electricity generation collects the reactive loss that booster system mainly exists _twith the reactive loss Δ Q in 750kV outlet _l; Wind-powered electricity generation is exerted oneself larger, and the reactive loss in main-transformer and 750kV outlet is also larger, and in net, the voltage of interdependent node is also lower.And the charge power Q of 750kV outlet _l/ 2 depend primarily on the voltage levvl of booster stations 750kV bus, Q under normal operating mode _l/ 2 amplitudes of variation are very little.

When the gross capability in wind-powered electricity generation base is very large, 750kV collects the reactive loss total amount of the interior main-transformer of booster stations and 750kV outlet much larger than the charge power of 750kV outlet, cause collecting booster stations voltage levvl on the low side, therefore can be by analysis and research along with the trend of the access voltage of new forms of energy is analyzed the regional impact of the concentrated access of judgement new forms of energy.

In step 2, obtain the PV curve of wind-powered electricity generation access substation bus bar under normal operating mode and the N-1 method of operation.

PV curve is one of instrument of static voltage stability analysis, by setting up the relation curve between busbar voltage and regional load or Section Tidal Current of Power Transmission, thereby provides regional load or section power level causes system to approach the degree of quiescent voltage collapse.

When conventional electric power system applies P-V tracing analysis voltage stability problem, the total load in P ordinary representation region, also can representative system transmit the through-put power on section or region interconnection; V represents the voltage of critical busses conventionally, also can draw the voltage curve of a plurality of buses simultaneously.

When PV curve method being applied to the static electric voltage stability analysis of wind energy turbine set access electrical network, due to needs consideration is that wind-powered electricity generation injects the impact of electrical network on voltage stability, P has represented the active power that whole wind energy turbine set is sent, and V can be both that set end voltage can be also grid-connected point voltage.

The analysis of application PV curve to the static electric voltage stability of wind energy turbine set access electrical network, the actual output of wind electric field that is the variation of research wind speed causes changes the impact on line voltage, adopt the way of simplifying small-disturbance voltage stability computing to be become to the Static Power Flow calculating of each discrete point on section continuous time, the variation of the voltage stability causing for the injecting power of studying wind-powered electricity generation and operating point, apart from the distance of collapse of voltage point, reflect the voltage stability margin of the electrical network that wind-powered electricity generation accesses; Can express meritorious the exerting oneself of wind-powered electricity generation causes whole system to close on the degree of collapse of voltage.

The method of P-V curve is from the current steady-state operation point of system, and the track of system change process is obtained in pointwise, and generally uses P-V point of inflexion on a curve as voltage stability limit state, comprises two kinds of repeated power flow method and continuity methods.

Repeated power flow method, tries to achieve P-V point of inflexion on a curve by constantly solving power flow equation; Continuity method, a kind of method that solves non-linear algebraic equation solution track.

When asking for wind energy turbine set P-V curve, except system balancing node, the not variation of the meritorious variation of exerting oneself in other generating plant and each node load in taking into account system, wherein, what P represented is active power of wind power field, the voltage of the bus that V represents to study (other buses in machine end bus site or electrical network).

According to < < guiding rules of power system safety and stability > > (DL755-2001), stipulate, under normal operating mode, to different electric system, the static stability reserve coefficient (Kv%) calculating by reactive voltage criterion meets 10%～15%.

Kv=(Uz-Uc)/Uz * 100%, wherein, Uz, Uc are respectively normal voltage and the critical voltage of bus.

In step 3, under normal operating mode and the N-1 method of operation, according to Wang Nei transformer station, access relevant wind-powered electricity generation and calculated PV curve respectively, obtained the critical voltage (Uc) of substation bus bar.

The N-1 method of operation refers to that the arbitrary independent component (generator, transmission line of electricity, transformer etc.) in N element of electric system breaks down and after cut, should not cause because of All other routes overload and trip and cause user to have a power failure, do not destroy the stability of system, do not occur the accidents such as collapse of voltage.

In step 4, according to the static stability reserve coefficient of above-mentioned critical voltage and system (Kv%, initial calculation is chosen Kv%=15%), the voltage minimum that this bus of calculating acquisition can reach is the normal voltage (Uz) of bus.

As shown in Figure 3, Fig. 3 is wind-powered electricity generation access substation bus bar critical voltage deterministic process schematic diagram; Along with the increase of exerting oneself of the wind-powered electricity generation on node, voltage reduces gradually, according to collapse point voltage and static stability reserve coefficient, calculates operating point voltage, and static stability reserve coefficient formula is suc as formula shown in (7):

K _v＝(U _z-U _c)/U _Z×100％ (7)

Wherein, K _vfor static stability reserve coefficient, U _cfor the critical voltage of bus, i.e. the point of collapse of voltage in Fig. 3, U _zfor the normal voltage of bus, i.e. voltage operating point in Fig. 3.According to the PV curve map calculating, can obtain corresponding the exerting oneself of voltage operating point, i.e. the theoretical wind-powered electricity generation capacity P receiving of this bus i _i.

In step 5, while obtaining corresponding normal voltage, access the wind-powered electricity generation capacity of this bus, the result obtaining under normal operating mode and the N-1 method of operation is compared, choose smaller value as the admissible wind-powered electricity generation capacity of this bus.

S501, corresponding the exerting oneself as the theory receiving wind-powered electricity generation capacity P of substation bus bar of the operating point of determining normal voltage according to described PV curve _i;

S502, the theory that obtains respectively single substation bus bar i under normal operating mode and the N-1 method of operation are received wind-powered electricity generation capacity P _iand Pi ( _n-1);

S603, the theory of determining single substation bus bar i under described normal operating mode and the N-1 method of operation receive wind-powered electricity generation capacity as shown in the formula (8):

P _ii＝min(P _i,P _i(N-1)) (8)

In formula, P _ifor the theory of single substation bus bar i under normal operating mode is received wind-powered electricity generation capacity, P _{i (N-1)}for the theory of single substation bus bar i under the N-1 method of operation is received wind-powered electricity generation capacity.

In step 6, according to the admissible wind-powered electricity generation amount of capacity of each bus, calculate the receiving energy force rate of receiving wind power bus in regional power grid, by this ratio and regional power grid wind-powered electricity generation access total amount, can draw each bus wind-powered electricity generation layout in regional power grid.

S601, determine that substation bus bar i wind-powered electricity generation in regional power grid receives ability such as following formula (9):

$K=P_{\mathrm{ii}}/\underset{i=1}{\mathrm{\&Sigma;}}{P}_{\mathrm{ii}}---\left(9\right);$

In formula, P _iifor the theory of single substation bus bar i under normal operating mode and the N-1 method of operation is received wind-powered electricity generation capacity;

In S602, definite area electrical network, each bus wind-powered electricity generation layout is as shown in the formula (10):

P _iw＝K·P _w (10)

In formula, P _wfor regional power grid wind-powered electricity generation access total amount.

In step 7, respectively the stability after each bus access calculating gained wind-powered electricity generation is carried out to verification and comprises:

Judge whether electrical network can meet transient stability, if meet, calculate and finish; If do not meet, adjust static stability reserve coefficient K _vif, K _vduring %=20%, still do not meet stability verification, judge that this bus cannot access wind-powered electricity generation, wind-powered electricity generation that this bus distributes proportionally accesses other bus.

The technical scheme in conjunction with specific embodiments the present invention being realized is described further.

As shown in Figure 4, Fig. 4 is simulation example system construction drawing; This system is regional power grid reduced graph, and wherein transformer station 1～4 is access wind-powered electricity generation substation bus bar, requires this region access wind-powered electricity generation total amount to be no more than 340MW.Setting the trend Ji Ge substation bringing onto load that needs major network support of whole Study system fixes.

Under normal mode and the N-1 method of operation, transformer station 1～4 is carried out respectively to PV curve calculation, wherein the result of calculation of transformer station 1 is as shown in Figure 5,6.

Under normal operating mode, the U of transformer station 1 _c=0.854pu, gets static stability reserve coefficient K _v=15%, corresponding operating point voltage U _z=0.9821pu.According to PV curve, obtain P corresponding to operating point voltage U z, wind-powered electricity generation is exerted oneself as P ₁=230MW.

Under the regional power grid N-1 method of operation, the critical point voltage U of transformer station 1 _{c (N-1)}=0.84pu, gets static stability reserve coefficient K _{v (N-1)}=15%, corresponding operating point voltage U _{z (N-1)}=0.966pu.According to PV curve, obtain operating point voltage U _{z (N-1)}corresponding P, wind-powered electricity generation is exerted oneself as P _{1 (N-1)}=209MW.

P ₁₁=209MW.

The result of calculation of transformer station 2～4 is as follows:

P ₁₁+P ₂+P ₃+P ₄＝209+184+216+90＝699MW

Each bus wind-powered electricity generation of this regional power grid is received and can force rate is:

K ₁＝209÷699＝0.299

K ₂＝184÷699＝0.263

K ₃＝216÷699＝0.309

K ₄＝90÷699＝0.129

The wind-powered electricity generation layout that can calculate this regional power grid is as follows:

P _1w＝K ₁×P _w＝0.299×340＝101.66MW.

P _2w＝K ₂×P _w＝0.263×340＝89.42MW.

P _3w＝K ₃×P _w＝0.309×340＝105.06MW.

P _4w＝K ₄×P _w＝0.129×340＝43.6MW.

After rounding, it is 100MW that access capacity is recommended by transformer station 1; Transformer station's 2 recommended maximum sizes are 90MW; Transformer station's 3 recommended maximum sizes are 105MW; Transformer station's 4 recommended maximum sizes are 45MW.

The stability that each bus is accessed after above-mentioned wind-powered electricity generation is carried out verification, finally judges that electrical network can meet transient stability, obtains and finishes.

Finally should be noted that: above embodiment is only in order to illustrate that technical scheme of the present invention is not intended to limit, although the present invention is had been described in detail with reference to above-described embodiment, those of ordinary skill in the field are to be understood that: still can modify or be equal to replacement the specific embodiment of the present invention, and do not depart from any modification of spirit and scope of the invention or be equal to replacement, it all should be encompassed in the middle of claim scope of the present invention.

Claims (7)

1. the regional power grid wind-powered electricity generation topological analysis method based on static electric voltage stability, is characterized in that: said method comprising the steps of:

I, on the network model of regional power grid, build wind-powered electricity generation and access idle characteristic model;

II, obtain the PV curve of the access of wind-powered electricity generation under normal operating mode and N-1 method of operation substation bus bar;

III, according to described PV curve, obtain the critical voltage of wind-powered electricity generation access substation bus bar;

IV, according to the static stability reserve coefficient of described critical voltage and system, obtain the normal voltage of described bus;

V, obtain wind-powered electricity generation capacity accessible under normal operating mode and the N-1 method of operation respectively, the theory that obtains substation bus bar is received wind-powered electricity generation capacity;

In VI, acquisition regional power grid, wind-powered electricity generation is received energy force rate, accesses total amount obtain each bus wind-powered electricity generation layout in regional power grid by described receiving energy force rate and regional power grid wind-powered electricity generation;

VII, the stability of respectively each bus access being calculated after gained wind-powered electricity generation are carried out verification.

2. analytical approach as claimed in claim 1, is characterized in that: in described step I, all wind-powered electricity generations in wind-powered electricity generation base are considered as to unit power supply, wind-powered electricity generation is exerted oneself after primary substation boosts by equivalent circuit access Infinite bus system;

Determine wind-powered electricity generation on-position, on the network model of regional power grid, build wind-powered electricity generation and access idle characteristic model.

3. analytical approach as claimed in claim 1, is characterized in that: in described Step II I, the PV curve that uses PV curve static voltage stability analysis method to obtain is determined the critical voltage of wind-powered electricity generation access substation bus bar.

4. analytical approach as claimed in claim 1, it is characterized in that: in described step IV, the increase of exerting oneself of wind-powered electricity generation on substation bus bar, voltage reduces gradually, according to the critical point voltage of described substation bus bar and static stability reserve coefficient, obtains respectively under normal operating mode and the N-1 method of operation operating point voltage as shown in the formula (1):

K _v＝(U _z-U _c)/U _Z×100％ (1)

Wherein, K _vfor static stability reserve coefficient, U _cfor the critical voltage of substation bus bar, U _zoperating point voltage for substation bus bar.

5. analytical approach as claimed in claim 1, is characterized in that: in described step V, comprise the following steps:

S501, corresponding the exerting oneself as the theory receiving wind-powered electricity generation capacity P of substation bus bar of the operating point of determining normal voltage according to described PV curve _i;

S502, the theory that obtains respectively single substation bus bar i under normal operating mode and the N-1 method of operation are received wind-powered electricity generation capacity P _iand P _{i (N-1)};

S603, the theory of determining single substation bus bar i under described normal operating mode and the N-1 method of operation receive wind-powered electricity generation capacity as shown in the formula (2):

P _ii＝min(P _i,P _i(N-1)) (2)

In formula, P _ifor the theory of single substation bus bar i under normal operating mode is received wind-powered electricity generation capacity, P _{i (N-1)}for the theory of single substation bus bar i under the N-1 method of operation is received wind-powered electricity generation capacity.

6. analytical approach as claimed in claim 1, is characterized in that: described step VI comprises the following steps:

S601, determine that substation bus bar i wind-powered electricity generation in regional power grid receives ability such as following formula (3):

$K=P_{\mathrm{ii}}/\underset{i=1}{\mathrm{\&Sigma;}}{P}_{\mathrm{ii}}---\left(3\right);$

In formula, P _iifor the theory of single substation bus bar i under normal operating mode and the N-1 method of operation is received wind-powered electricity generation capacity;

In S602, definite area electrical network, each bus wind-powered electricity generation layout is as shown in the formula (4):

P _iw＝K·P _w (4)

In formula, P _wfor regional power grid wind-powered electricity generation access total amount.

7. analytical approach as claimed in claim 1, is characterized in that: in described step VII, respectively each bus access is calculated to stability after gained wind-powered electricity generation and carry out verification and comprise:

Judge whether electrical network can meet transient stability, if meet, calculate and finish; If do not meet, adjust static stability reserve coefficient K _vif, K _vduring %=20%, still do not meet stability verification, judge that this bus cannot access wind-powered electricity generation, wind-powered electricity generation that this bus distributes proportionally accesses other bus.