CN104319820B - Many small hydropower system based on Practical Dynamic Security Region send Capacity Coordination optimization method - Google Patents

Abstract

The invention provides a kind of many small hydropower system based on Practical Dynamic Security Region and send Capacity Coordination optimization method, comprise the following steps: 1) select critical hyperplane equation in Practical Dynamic Security RegionIn variable, whereinIt is that electrical network injects meritorious power and variable,It is equation coefficient,It it is variable number；2) coefficient of critical hyperplane equation is solved；3) set up the Coordination and Optimization Model that the many small hydropower system with critical hyperplane as constraints are sent, and use Linear Programming.A kind of based on Practical Dynamic Security Region many small hydropower system that the present invention provides send Capacity Coordination optimization method, it is possible to coordinate the size of exerting oneself of multiple small hydropower system, are always sent the optimum results that ability is maximum.

Description

Many small hydropower system based on Practical Dynamic Security Region send Capacity Coordination optimization method

Technical field

The present invention is belonging to field of power, is specifically related to a kind of many small hydropower system based on Practical Dynamic Security Region and send The coordination optimizing method of output capacity.

Background technology

The area abundant at small hydropower resources is generally off-site from load center, weak with grid contact, therefore small hydropower system Ability of sending mainly is restricted by dynamic stability problem.And when multiple small hydropower system are concentrated and sent, different small hydropower system Between unit often due to participate in identical oscillation mode and influence each other, thus cause ability of sending the also phase of small hydropower system Mutually impact, increase that the ability of sending of a small hydropower system may reduce another small hydropower system sends ability.

The ability of sending of small hydropower system is typically carried out just for single small hydropower system unit, multiple small hydropower system send energy The constellation of power does not considers.How to describe the influencing each other of ability of sending of multiple small hydropower system, and realize The research of ability of always the sending maximum of multiple small hydropower system is less.Therefore the coordination that a kind of many small hydropower system send ability is studied excellent Change method, it is achieved ability of always the sending maximum of multiple small hydropower system has practical value.

Summary of the invention

For the problems referred to above, the invention provides a kind of based on many small hydropower system of practical state security domain send ability Coordination optimizing method, the present invention can send Capacity Coordination by multiple small hydropower system, it is achieved what many small hydropower system were total sends energy The purpose that power is maximum.

Technical scheme is as follows:

The present invention many small hydropower system based on Practical Dynamic Security Region send Capacity Coordination optimization method, dynamic based on practicality Many small hydropower system of security domain send Capacity Coordination optimization method, it is characterised in that comprise the following steps that

1) critical hyperplane equation in Practical Dynamic Security Region is selectedIn variable, wherein P_iIt is that electrical network is noted Enter active power variable, α_iBeing equation coefficient, n is variable number；

2) factor alpha of critical hyperplane equation is solved_i；

3) set up the Coordination and Optimization Model that the many small hydropower system with critical hyperplane as constraints are sent, and use linear Law of planning solves.

A kind of based on Practical Dynamic Security Region many small hydropower system that the present invention provides send Capacity Coordination optimization method, energy Enough coordinate the size of exerting oneself of multiple small hydropower system, obtain the optimum results that total ability of sending is maximum.

Accompanying drawing explanation

Fig. 1 is the flow process that the present invention many small hydropower system based on Practical Dynamic Security Region send Capacity Coordination optimization method Figure.

Detailed description of the invention

The present invention many small hydropower system based on Practical Dynamic Security Region send Capacity Coordination optimization method, include following step Rapid:

1) critical hyperplane equation in Practical Dynamic Security Region is selectedIn variable, wherein P_iIt is that electrical network is noted Enter active power variable, α_iBeing equation coefficient, n is variable number；

2) factor alpha of critical hyperplane equation is solved_i；

3) set up the Coordination and Optimization Model that the many small hydropower system with critical hyperplane as constraints are sent, and use linear Law of planning solves.

Described step 1) comprise the following steps:

11) by simulation calculation determine restriction small hydropower system send ability Critical inertial modes and generating set Participation factors, and using the injection active power of each unit as the candidate variables collection of hyperplane equation；

12) according to capacity, position and the participation factors size of candidate's unit, therefrom filter out corresponding unit, be injected into Active power is as the variable of hyperplane equation.

Described step 11) in, first with transient stability time-domain-simulation, determine the section peace treaty that restriction small hydropower system is sent Bundle fault, then utilizes Pu Luoni (Prony) to analyze and obtains corresponding Critical inertial modes, finally utilize dynamic stability frequency domain Emulation, determines the generating set that the participation factors of participation Critical inertial modes is big.

Described step 12) in, according to candidate's unit small hydropower system send the position of section be divided into small power station's side unit and Major network side unit, to major network side unit, according to the size of candidate's unit participation factors, retains and participates in control oscillation modes degree relatively Big unit, other units and load inject and process as constant.To small power station's side unit, according to candidate's unit participation factors and The size of capacity, retains and participates in the more unit of control oscillation modes, the unit that reserve capacity is bigger, remaining small power station's machine Group carries out classification merging by sending branch road.Load injects and processes as constant.

Described step 2) comprise the following steps:

21) by the way of being gradually increased unit output, search small hydropower system send a critical temperature rise of the limit (P_i0,P₂₀,…,P_n0), this critical temperature rise is positioned on critical hyperplane, the most satisfied $\underset{i=1}{\overset{n}{\mathrm{\Σ}}}{\mathrm{\α}}_i{P}_{i0}=1;$

22) at above-mentioned critical temperature rise, optional variable P_kAnd P_m, search two newly by the corresponding unit output of increase and decrease Critical temperature rise (P_k+△P_k1,P_m+△P_m1) and (P_k+△P_k2,P_m+△P_m2).Substitute into equationα can be obtained_m With α_kRelational expression:In like manner obtain other coefficient and α_kRelation: α_i=K_ikα_k.By critical Point of safes (P_i0,P₂₀,…,P_n0) and α_i=K_ikα_k, substitute into equationObtain coefficient value ${\mathrm{\α}}_i=\frac{K_{\mathrm{ik}}}{P_{k0}+\underset{i=1}{\overset{n}{\mathrm{\Σ}}}{K}_{\mathrm{ik}}{P}_{i0}}.$

Described step 22) in, calculate hyperplane equation coefficient method particularly includes: 1. at critical temperature rise, arbitrarily select Select an active power and inject variable P_kFor known quantity, its hyperplane coefficient is α_k, it is P that active power to be asked injects variable_m, Hyperplane coefficient is α_m, other injecting power is as constant.Search on critical hyperplane by increasing and decreasing corresponding unit output Two critical temperature rise (P_k+△P_k1, P_m+△P_m1) and (P_k+△P_k2,P_m+△P_m2).2. according to hyperplane equation Two critical temperature rise with obtaining, can obtain α_kAnd α_mProportionate relationship,3. by with Upper method can obtain other coefficient and α_kProportionate relationship: α_i=K_ikα_k.4. close according to the ratio between critical temperature rise and coefficient System, tries to achieve coefficient value ${\mathrm{\α}}_i=\frac{K_{\mathrm{ik}}}{P_{k0}+\underset{i=1}{\overset{n}{\mathrm{\Σ}}}{K}_{\mathrm{ik}}{P}_{i0}}.$

Described step 3) comprise the following steps:

31) optimization aim that small hydropower system is coordinated to send isWherein P_bkIt is that kth small hydropower system is sent Section power.If load bus power is constant, then sends power and can be described as incremental form, i.e.Wherein △ P_iIt it is the active power increment of i-th unit.Now small hydropower system coordination optimum sends problem can be converted into unit injection joint Point increment coordinates optimal problem, i.e. $\mathrm{Max}\underset{k=1}{\overset{m}{\mathrm{\Σ}}}\left(\underset{i\∈S_k}{\mathrm{\Σ}}\mathrm{\Δ}{P}_i\right).$

32) coordination of small hydropower system is sent and can be described as following optimization problem:

Optimization aim: $\mathrm{Max}\underset{k=1}{\overset{m}{\mathrm{\Σ}}}\left(\underset{i\∈S_k}{\mathrm{\Σ}}\mathrm{\Δ}{P}_i\right)$

Constraints: $\left[\begin{array}{cccc}{a}_{11}& a_{12}& \·\·\·& a_{1n}\\ a_{21}& a_{22}& \·\·\·& a_{2n}\\ \·\·\·& \·\·\·& \·\·\·& \·\·\·\\ a_{m1}& a_{n2}& \·\·\·& a_{\mathrm{mn}}\end{array}\right]\left[\begin{array}{c}{P}_1\\ P_2\\ \·\·\·\\ P_n\end{array}\right]\≤\left[\begin{array}{c}1-{\mathrm{\ϵ}}_1\\ 1-{\mathrm{\ϵ}}_2\\ \·\·\·\\ 1-{\mathrm{\ϵ}}_m\end{array}\right]$

P_imin≤P_i≤P_imax, i=1,2 ... n

Wherein S_kBeing belonging to all meritorious injection node set that kth small hydropower system is sent, constraints is each little water The critical hyperplane constraint specification that electricity group sends is matrix form.ε_mIt is the margin of safety sent of m-th small hydropower system, P_iminWith P_imaxIt is the meritorious upper lower limit value injecting node Pi respectively.

This optimization problem belongs to linear programming problem, and Matlab linear programming function can be used to solve.

33) small hydropower system after checking optimizes sends the raising effect of ability.

Described step 31) comprise the following steps:

Small hydropower system sends the power of section can be gained merit injecting power by the unit of small power station side and load determines jointly, I.e.Wherein S_kIt is belonging to the injection node set of all units of kth small hydropower system, wherein L_kIt is to belong to All loads in kth small hydropower system inject node set.Calculate for simplifying, it is assumed that the initial power that small hydropower system is sent is P_bk0, the initial power that each unit injects is P_i0, the initial power of each load bus is constant, then the small hydropower system after optimizing is sent Power can be described as incremental form, i.e.Now the coordination optimum of small hydropower system sends problem, can convert The increment injecting node for all units coordinates optimal problem, can be described as:

Optimization aim: $\mathrm{Max}\underset{k=1}{\overset{m}{\mathrm{\Σ}}}\left(\underset{i\∈S_k}{\mathrm{\Σ}}\mathrm{\Δ}{P}_i\right)$

Constraints: $\left[\begin{array}{cccc}{a}_{11}& a_{12}& \·\·\·& a_{1n}\\ a_{21}& a_{22}& \·\·\·& a_{2n}\\ \·\·\·& \·\·\·& \·\·\·& \·\·\·\\ a_{m1}& a_{n2}& \·\·\·& a_{\mathrm{mn}}\end{array}\right]\left[\begin{array}{c}{P}_1\\ P_2\\ \·\·\·\\ P_n\end{array}\right]\≤\left[\begin{array}{c}1-{\mathrm{\ϵ}}_1\\ 1-{\mathrm{\ϵ}}_2\\ \·\·\·\\ 1-{\mathrm{\ϵ}}_m\end{array}\right]$

P_imin≤P_i≤P_imax, i=1,2 ... n

Wherein S_kBeing belonging to all meritorious injection node set that kth small hydropower system is sent, constraints is each little water The critical hyperplane constraint specification that electricity group sends is matrix form.ε_mIt is the margin of safety sent of m-th small hydropower system, P_iminWith P_imaxIt is meritorious injection node P respectively_iUpper lower limit value.

Described step 32) in, the object function of optimization problem and constraints are all the linear functions of node active power, Utilize Matlab software can solve above linear programming problem, obtain each small hydropower system and send the coordination optimal result of ability.

Described step 33) in, individually carry out the optimization of small hydropower system, compare with the result of complex optimum, then calculate Optimum results under different margins of safety, verifies the margin of safety impact on sending ability.

Below in conjunction with the application in actual electric network, the present invention will be further described.

Use the inventive method to Baoshan of Yunnan Power System West Yunnan, Nujiang and enlightening celebrating small hydropower system to send power big Little coordinate optimization, to improve the ability of totally sending of three small hydropower system, verify the effectiveness of the inventive method.Specifically Implementation process is as follows:

Step one: by transient stability time-domain-simulation N-1 fault scanning, determines that the restriction Baoshan, Nujiang and enlightening celebrate this little water Electricity group sends section and constraint fault, is analyzed by Prony and obtains corresponding Critical inertial modes frequency.Then by dynamically Stablize simulation in the frequency-domain scanning, Critical inertial modes is carried out model analysis, determine the ginseng participating in Critical inertial modes The generating set big with the factor, result is as shown in table 1.

Table 1 Critical inertial modes and the big unit of participation factors

Step 2: unit is divided into small power station's side unit and major network side unit by the limited section sent according to small hydropower system. To major network side unit, retain the participation more unit of control oscillation modes, other units and load and inject at as constant Reason.Small power station's side unit, retains and participates in the more unit of control oscillation modes, and the unit that reserve capacity is bigger, remaining is little Hydropower Unit carries out classification merging by sending branch road.Load injects and processes as constant.Dimensionality reduction the results are shown in Table 2.

Table 2 small hydropower system active power Injection Space dimensionality reduction result table

Step 3: use the critical hyperplane method for solving improved to obtain the coefficient of hyperplane equation.Mode is by progressively Increase the mode of unit output to search one of Baoshan small hydropower system and send limit critical temperature rise, then utilize this critical surely Fixed point, the proportionate relationship between each coefficient and numerical value in calculating hyperplane equation.Recycling the method obtains Nujiang and enlightening celebrating is little Ratio between coefficient and numerical value in water power group's hyperplane equation.Result of calculation is shown in Table 3.

Table 3 small hydropower system sends main critical hyperplane equation coefficient table

Step 4: the coordination optimum of the Baoshan, Nujiang and enlightening celebrating small hydropower system is sent problem, is converted into unit and injects node Increment coordinates optimal problem, is i.e. converted intoWherein △ P₉=△ P_{Ah turtledove field}, i.e. the 9th corresponding unit in table 3 Ah turtledove gains merit in field injecting power increment, by that analogy.

Step 5: utilize Matlab to solve above-mentioned linear programming problem, obtain optimal solution result.According to result after optimizing, The Baoshan, Nujiang and enlightening celebrating water power group's unit can on the basis of initial launch point the most respectively increase send 15MW, 42MW and 10MW.

Step 6: the small hydropower system after checking optimization sends the raising effect of ability.

Table 4 gives and individually optimizes the Baoshan, Nujiang and the optimum results of enlightening celebrating small hydropower system.Permissible from result of calculation Find out, one small hydropower system of single optimization send result, the corresponding optimal value sending section more than in complex optimum result, but Global optimization result is the most far short of what is expected.I.e. by complex optimum, that can coordinate multiple small hydropower system sends ability, reaches Excellent result.

In order to ensure safe operation, actual motion needs arrange certain margin of safety.It is abundant that table 5 gives different safety Result of calculation under Du.It can be seen that along with the increase of margin of safety, the limit of sending of each small hydropower system progressively declines.

Optimum results contrast table under table 4 Different Optimization target

The different margin of safety of table 5 optimum results affected table

The present invention combines actual application and describes the enforcement of the present invention in detail and describe, and above example is only this Bright preferred embodiment, illustrates to be intended merely to help reader to be more fully understood that present invention spirit, and not the present invention is protected model The restriction enclosed, any spirit improvements introduced based on the present invention or modification all should fall within the scope and spirit of the invention.

Claims (9)

1. many small hydropower system based on Practical Dynamic Security Region send Capacity Coordination optimization method, it is characterised in that include Following steps:

1) critical hyperplane equation in Practical Dynamic Security Region is selectedIn variable, wherein P_iIt is that electrical network is injected with Merit power and variable, α_iBeing equation coefficient, n is variable number；

2) factor alpha of critical hyperplane equation is solved_i；

3) set up the Coordination and Optimization Model that the many small hydropower system with critical hyperplane as constraints are sent, and use linear programming Method solves；

Described step 1) comprise the following steps:

11) determine that restriction small hydropower system sends the Critical inertial modes of ability and the participation of generating set by simulation calculation The factor, and using the injection active power of each unit as the candidate variables collection of hyperplane equation；

12) according to capacity, position and the participation factors size of candidate's unit, therefrom filter out corresponding unit, be injected into meritorious Power is as the variable of hyperplane equation.

Many small hydropower system based on Practical Dynamic Security Region the most according to claim 1 send Capacity Coordination optimization method, It is characterized in that described step 11) in, first with transient stability time-domain-simulation, determine section that restriction small hydropower system sends and Constraint fault, then utilizes Pu Luoni (Prony) to analyze and obtains corresponding Critical inertial modes, finally utilize dynamic stability frequency Territory emulates, and determines the generating set that the participation factors of participation Critical inertial modes is big.

Many small hydropower system based on Practical Dynamic Security Region the most according to claim 1 send Capacity Coordination optimization method, It is characterized in that described step 12) in, it is divided into small power station's side unit according to the position that candidate's unit sends section at small hydropower system With major network side unit, to major network side unit, according to the size of candidate's unit participation factors, retain and participate in control oscillation modes degree Bigger unit, other units and load inject and process as constant；To small power station's side unit, according to candidate's unit participation factors With the size of capacity, retain and participate in the more unit of control oscillation modes, the unit that reserve capacity is bigger, remaining small power station Unit carries out classification merging by sending branch road, and load injects and processes as constant.

Many small hydropower system based on Practical Dynamic Security Region the most according to claim 1 send Capacity Coordination optimization method, It is characterized in that described step 2) comprise the following steps:

21) by the way of being gradually increased unit output, search small hydropower system send a critical temperature rise (P of the limit_i0, P₂₀,…,P_n0), this critical temperature rise is positioned on critical hyperplane, the most satisfied

22) at above-mentioned critical temperature rise, optional variable P_kAnd P_m, search two new facing by the corresponding unit output of increase and decrease Boundary point of safes (P_k+ΔP_k1,P_m+ΔP_m1) and (P_k+ΔP_k2,P_m+ΔP_m2), substitute into equationObtain α_mWith α_kPass It is formula:In like manner obtain other coefficient and α_kRelation: α_i=K_ikα_k, by critical temperature rise (P_i0,P₂₀,…,P_n0) and α_i=K_ikα_k, substitute into equationObtain coefficient value

Many small hydropower system based on Practical Dynamic Security Region the most according to claim 4 send Capacity Coordination optimization method, It is characterized in that described step 22) in, calculate hyperplane equation coefficient method particularly includes: 1. at critical temperature rise, arbitrarily An active power is selected to inject variable P_kFor known quantity, its hyperplane coefficient is α_k, active power to be asked is injected variable and is P_m, hyperplane coefficient is α_m, other injecting power, as constant, searches on critical hyperplane by increasing and decreasing corresponding unit output Two critical temperature rise (P_k+ΔP_k1, P_m+ΔP_m1) and (P_k+ΔP_k2,P_m+ΔP_m2), 2. according to hyperplane equationTwo critical temperature rise with obtaining, obtain α_kAnd α_mProportionate relationship,③ Obtain other coefficient and α by the above process_kProportionate relationship: α_i=K_ikα_k, 4. close according to the ratio between critical temperature rise and coefficient System, tries to achieve coefficient value

Many small hydropower system based on Practical Dynamic Security Region the most according to claim 1 send Capacity Coordination optimization method, It is characterized in that described step 3) comprise the following steps:

31) optimization aim that small hydropower system is coordinated to send is MaxWherein P_bkIt is that kth small hydropower system sends section merit Rate, if load bus power is constant, then sends power and is described as incremental form, i.e.Wherein Δ P_iIt it is i-th The active power increment of unit, now small hydropower system coordination optimum is sent problem and is converted into unit injection node increment coordination optimum Problem, i.e. Max

32) coordination of small hydropower system is sent and is described as following optimization problem:

Optimization aim: Max

Constraints:

P_imin≤P_i≤P_imax, i=1,2 ... n

Wherein S_kBeing belonging to all meritorious injection node set that kth small hydropower system is sent, constraints is that each small hydropower system send The critical hyperplane constraint specification gone out is matrix form；ε_mIt is the margin of safety sent of m-th small hydropower system, P_iminAnd P_imaxPoint It not meritorious injection node P_iUpper lower limit value；

33) small hydropower system after checking optimizes sends the raising effect of ability.

Many small hydropower system based on Practical Dynamic Security Region the most according to claim 6 send Capacity Coordination optimization method, It is characterized in that described step 31) comprise the following steps:

Small hydropower system is sent the power of section and is gained merit injecting power by the unit of small power station side and load determines, i.e. jointlyWherein S_kIt is belonging to the injection node set of all units of kth small hydropower system, wherein L_kIt is belonging to All loads of kth small hydropower system inject node set, calculate for simplifying, it is assumed that the initial power that small hydropower system is sent is P_bk0, the initial power that each unit injects is P_i0, the initial power of each load bus is constant, then the small hydropower system after optimizing is sent Power is described as incremental form, i.e.Now the coordination optimum of small hydropower system sends problem, is converted into institute organic Group is injected the increment of node and is coordinated optimal problem, is described as:

Optimization aim: Max

Constraints:

P_imin≤P_i≤P_imax, i=1,2 ... n

Wherein S_kBeing belonging to all meritorious injection node set that kth small hydropower system is sent, constraints is that each small hydropower system send The critical hyperplane constraint specification gone out is matrix form, ε_mIt is the margin of safety sent of m-th small hydropower system, P_iminAnd P_imaxPoint It not meritorious injection node P_iUpper lower limit value.

Many small hydropower system based on Practical Dynamic Security Region the most according to claim 6 send Capacity Coordination optimization method, It is characterized in that described step 32) in, the object function of optimization problem and constraints are all the linear letters of node active power Number, solves above linear programming problem, obtains each small hydropower system and send the coordination optimal result of ability.

Many small hydropower system based on Practical Dynamic Security Region the most according to claim 6 send Capacity Coordination optimization method, It is characterized in that described step 33) in, individually carry out the optimization of small hydropower system, compare with the result of complex optimum, then count Calculate the optimum results under different margin of safety, verify the margin of safety impact on sending ability.