CN101299534A - Power system temporary stability and thermal stabilization cooperativeness emergency control method - Google Patents

Abstract

A power system transient stability and thermal stability coordination emergency control method, includes the following steps: (1) computing the integration sensitivity index of the optional measurement of the thermal stability emergency control and computing the thermal stability emergency control strategy based on the index; (2) checking the transient stability after implementing the thermal stability emergency control strategy, if true, the thermal stability emergency control strategy is used as the coordination emergency control strategy and the computation stops; else, searching the transient stability control strategy; (3) checking the thermal stability after implementing the thermal stability emergency control strategy, if the thermal stability of the electric network comes up to the standard, the computation stops; else switching to the step (1). The invention solves the stability problem meanwhile advances the margin of other stability, enhances the efficiency of the next solution process, finally ensures the high efficiency and the validity of the whole coordination emergency control strategy.

Description

Electric power system transient stability and thermally-stabilised coordination emergency control method

Technical field

The present invention relates to a kind of universal automatic identifying method of power pool multi-area dynamic operation method, bright genus dispatching automation of electric power systems field.

Background technology

Because power system operation is increasingly sophisticated, POWER SYSTEM EMERGENCY CONTROL becomes one of necessary means of maintenance system stable operation.POWER SYSTEM EMERGENCY CONTROL takes measures such as cutter, cutting load to make system keep stable operation after being meant accident.The stability of electric power system comprises power system transient stability and thermal stability from function, and transient stability comprises transient state angle stability, transient voltage stability and transient frequency stability.Wherein one or more stability problems appear down in forecast failure, and promptly there is very big hidden danger in electrical network even can not normally moves, and therefore need to implement the emergency control measure.

Delivered at present document or existing only use all transient stability emergency control and thermally-stabilised emergency control isolated come, often only consider wherein a kind of function or fail both are coordinated to consider, its shortcoming is to consider that perhaps the controlling schemes of wherein a certain stability requirement can not solve other stability problems of electric power system, even can bring negative effect to other stability requirements.Such control decision is in the specific a kind of stability requirement of specific aim resolution system, to the understanding of other stability problems of system or be in unknown state, or powerless.Therefore the practical application of only considering electric power transient stability or heat-staple emergency control is reliable inadequately and powerful.Therefore, the present invention proposes the step and the method for electric power system transient stability and thermally-stabilised coordination emergency control, this is the new trial of making on theory research and practice operation experience accumulation basis.

Summary of the invention

The present invention proposes step and method that electric power system transient stability emergency control and thermally-stabilised emergency control are carried out under coordinating frame, its purpose is: according to operation of power networks state, model and parameter, forecast failure scene, discern improving the optional controlling object of power system transient stability and thermal stability (as generator, load etc.), obtain correct and complete emergency control scheme, when guaranteeing that electric power system is broken down, keep transient stability and thermal stability.When calculating the coordination emergency control policy, the coordination step and the method for appropriate design transient stability emergency control and thermally-stabilised emergency control proposed, find the solution efficient and the validity of coordinating emergency control policy with raising, satisfy the requirement of online application.

The technical solution adopted for the present invention to solve the technical problems is as follows: electric power system transient stability and thermally-stabilised coordination emergency control method, and its step is as follows:

(1) according to operation of power networks state, model and parameter, forecast failure scene, carrying out thermally-stabilised assessment of electrical network and thermally-stabilised emergency control policy calculates, comprise: the overall sensitivity index of calculating the optional measure of thermally-stabilised emergency control, calculate thermally-stabilised emergency control policy based on this index, go to step (2);

(2) according to operation of power networks state, model and parameter, forecast failure scene, carry out assessment of electrical network transient stability and transient stability emergency control policy search calculating, comprising:

Transient stability assessment: check the transient stability that the back electrical network is implemented in thermally-stabilised emergency control measure;

If this moment, electrical network was a transient stability, then described thermally-stabilised emergency control policy as transient stability and heat-staple coordination emergency control policy, calculate termination; If electrical network transient state instability then will be carried out the Transient Stability Control decision search and be calculated on the basis that these control measure are implemented this moment;

Calculate the temporary stability energy index of the optional measure of transient stability emergency control, calculate the transient stability emergency control policy based on this index;

(3) check the thermal stability coordinated electrical network after the measure of transient stability emergency control, if the thermal stability of electrical network has reached the standard of actual needs, then whole coordination emergency control policy calculation process stops; If electrical network still has thermally-stabilised problem, then go to step (1).

Beneficial effect of the present invention is as follows: the present invention proposes step and method that electric power system transient stability emergency control and thermally-stabilised emergency control are carried out first under the framework of coordinating, and has broken through the thinking of existing such problem of solution.Be characterized in, take into full account under same running status of electrical network and the forecast failure, the similitude and the particularity of the transient stability problem that takes place and the internal cause of thermally-stabilised problem, with transient stability emergency control and thermally-stabilised emergency control process iterative, the functional module that solves thermally-stabilised problem or transient state problem keeps independent.By iteration, be expected to when solving a certain stability problem, improve the nargin of other stability problems of system.Improve the efficient of follow-up solution procedure, the high efficiency and the validity of whole coordination emergency control policy are found the solution in final assurance.When only there is wherein certain stable subproblem in system, the controlling schemes that this method obtains can guarantee can negative effect not arranged to other stability problems, when there is a plurality of stability problem in system, provide the complete controlling schemes that satisfies each stability requirement simultaneously, therefore its controlling schemes has more reliability and using value, and its result of decision can be the dispatcher and the aid decision support is provided or directly implements for automation mechanized operation

Description of drawings

Fig. 1 electric power system transient stability and thermally-stabilised coordination emergency control flow chart.

The angle stability of Fig. 2 electric power system transient stability, stable, the frequency stabilization coordination emergency control block diagram of voltage.

Embodiment

With reference to the accompanying drawings and in conjunction with the embodiments the present invention is described in further detail.But the invention is not restricted to given example.

Electric power system transient stability of the present invention and thermally-stabilised coordination emergency control method, its step is as follows:

(1) according to operation of power networks state, model and parameter, forecast failure scene, carrying out thermally-stabilised assessment of electrical network and thermally-stabilised emergency control policy calculates, comprise: the overall sensitivity index of calculating the optional measure of thermally-stabilised emergency control, calculate thermally-stabilised emergency control policy based on this index, go to step (2);

(2) according to operation of power networks state, model and parameter, forecast failure scene, carry out assessment of electrical network transient stability and transient stability emergency control policy search calculating, comprising:

Transient stability assessment: check the transient stability that the back electrical network is implemented in thermally-stabilised emergency control measure;

If this moment, electrical network was a transient stability, then described thermally-stabilised emergency control policy as transient stability and heat-staple coordination emergency control policy, calculate termination; If electrical network transient state instability then will be carried out the Transient Stability Control decision search and be calculated on the basis that these control measure are implemented this moment;

Calculate the temporary stability energy index of the optional measure of transient stability emergency control, calculate the transient stability emergency control policy based on this index;

(3) check the thermal stability coordinated electrical network after the measure of transient stability emergency control, if the thermal stability of electrical network has reached the standard of actual needs, then whole coordination emergency control policy calculation process stops; If electrical network still has thermally-stabilised problem, then go to step (1).

Can calculate transient stability and thermally-stabilised coordination emergency control policy by iteration.

In order to finish transient stability emergency control policy search calculating in the above-mentioned steps (2), the target that has defined Transient Stability Control is a solution transient state angle stability, voltage is stable and the frequency stabilization problem, still finishes the coordination emergency control between the three.Carry out according to the following steps: at first, search transient state angle stability emergency control policy, its control strategy is as the transient stability emergency control policy; Then, the search transient voltage is stablized emergency control policy, and its control strategy is to be on the initial value basis with transient state angle stability control measure, coordinates control measure; At last, the search transient frequency is stablized emergency control policy, and its control strategy is that the Transient Stability Control measure that obtains in above two steps is on the initial value basis, coordinates control measure.

In the present invention, the technology of the thermally-stabilised emergency control employing of the described electric power system of step (1) is the search technique based on the overall sensitivity index of control measure.The computational methods of overall sensitivity index are as follows:

If L apparatus overload arranged under the forecast failure, so the overall sensitivity index of measure i calculates by the formula following formula:

${\mathrm{PI}}_i=\frac{(\underset{j=1}{\overset{L}{\mathrm{\Σ}}}{S}_{\mathrm{ij}}\·W_j)\×P_{\mathrm{ti}}}{C_i}---\left(1\right)$

Wherein, P _TiFor press temporary stability that the EEAC quantification theory calculates can index (for first iterative process, P _TiValue be set to 1);

S _IjBe the control sensitivity of measure i under the fault for overload equipment j;

C _iControl cost for measure i;

W _jOverload degree for overload equipment.Calculate by following formula:

$W_j={\left(\frac{P_{j,\mathrm{now}}}{P_{j,\mathrm{rate}}}\right)}^2---\left(2\right)$

Wherein, P _{J, now}Actual active power for overload equipment;

P _{J, rate}Specified active power for overload equipment.

Calculate thermally-stabilised emergency control policy process, according to the descending order of overall sensitivity index optional control measure are sorted, increasing control measure according to this sequence sounds out, and the calculating electric network swim, the set of selected control measure was thermally-stabilised emergency control policy when electrical network no longer included thermally-stabilised problem after control measure apply.

In the present invention, the search of the described transient stability emergency control policy of step (2) based on the EEAC quantification theory (see quantification theory: the stability analysis of the non-linear multi-rigid-body system of Non-Self-Governing/Xue Yusheng work. Nanjing: Jiangsu science tech publishing house, 1999.12).Utilize the EEAC quantification theory to calculate the hive off information and the participation factors of electric power system control measure.The temporary stability that calculates measure in the transient stability emergency control policy search procedure based on hive off information and participation factors can index.

Calculate transient stability emergency control policy process, can optional control measure be sorted the index order according to temporary stability, increasing control measure according to this sequence sounds out, and electrical network carried out the transient stability simulation analysis, straight simulation result shows system stability, and the set of selected control measure is the transient stability emergency control policy.

From accompanying drawing 1,1. be to form transient stability and the required every file of thermally-stabilised coordination emergency control policy calculating, and file is read in internal memory according to operation of power networks state, model and parameter, forecast failure scene.Read whole coordination emergency control input file, these files comprise the trend file, stablize file, bug list file, measure list file, unbound document.Wherein, comprised the definition card of the relevant surveillance equipment of thermally-stabilised control in the bug list file, but the card index of thermally-stabilised control and Transient Stability Control control means, but the measure list file has comprised the definition card of coordinating all control means of emergency control.Unbound document is that programmed algorithm is realized relevant configuration file.2. be the flow process iterations initialization that to coordinate emergency control.3. be that whole coordination process at first carries out the evaluation process of thermal stability evaluation and control to electrical network, or after having passed through transient stability decision search process in the iterative process electrical network carried out thermal stability evaluation once more.4. be that electrical network thermal stability evaluation result is judged, if electrical network is heat-staple at this moment, enter step 5., otherwise enter step 6..5. for assessing under the thermal stability prerequisite further judge whether it is first iterative process for electrical network, if, change assessment and control that electrical network carries out transient stability over to, be step 7., otherwise show after the Transient Stability Control electrical network and be heat-staple, at this moment transient stability emergency control policy in the last iteration process is stopped as coordinating emergency control policy, calculating, enter step

6. for calculating thermally-stabilised emergency control policy, at first calculate the overall sensitivity index of measure, if first iterative process, the control strategy search of starting from scratch, otherwise on the basis that the measure of transient stability emergency control is implemented, carry out thermally-stabilised control strategy search calculating.After 7. step is thermally-stabilised emergency control, electrical network is carried out the transient stability assessment, appraisal procedure is utilized the EEAC quantification theory.8. step is that electrical network transient stability assessment result is judged, if electrical network is transient stability at this moment, show thermally-stabilised control back electrical network and be transient stability, at this moment with the 6. thermally-stabilised emergency control policy of step as coordinating emergency control policy, calculate termination, enter step

Otherwise enter step 9..Step is at first calculated the temporary stability energy index of measure 9. for calculating transient stability emergency control policy process, carries out the Transient Stability Control decision search and calculate on the basis that thermally-stabilised emergency control measure is implemented.Iterations adds 1, and returns step 3., enters the next round iterative process.

From accompanying drawing 2, at first, calculate transient state angle stability emergency control policy, its control strategy is as the transient stability emergency control policy; Then, calculate transient voltage and stablize emergency control policy, its control strategy is to be on the initial value basis with transient state angle stability control measure, coordinates control measure.Its implication is if control strategy did not make transient state merit angle from the stable instability that becomes after transient voltage was stablized emergency control, to admit and coordinate control measure renewal transient stability emergency control policy, otherwise give up this control measure; At last, calculate transient frequency and stablize emergency control policy, its control strategy is that the Transient Stability Control measure that obtains in above two steps is on the initial value basis, coordinates control measure.Its implication is, if control strategy did not make transient state merit angle or transient voltage become instability from stablizing after transient frequency stablize emergency control, this strategy as the transient stability emergency control policy, otherwise given up this strategy.

More than electric power system transient stability that the present invention is proposed and the step and the method for thermally-stabilised coordination emergency control method have been described in detail, and scope of the present invention should not be limited to these explanations.The technical scheme of parameter using method in the coordination approach of certain step or the coordination process wherein in all this coordination approach of employing all drops within protection scope of the present invention.

Claims (3)

1, electric power system transient stability and thermally-stabilised coordination emergency control method, step is as follows:

(1) according to operation of power networks state, model and parameter, forecast failure scene, carrying out thermally-stabilised assessment of electrical network and thermally-stabilised emergency control policy calculates, comprise: the overall sensitivity index of calculating the optional measure of thermally-stabilised emergency control, calculate thermally-stabilised emergency control policy based on this index, go to step (2);

(2) according to operation of power networks state, model and parameter, forecast failure scene, carry out assessment of electrical network transient stability and transient stability emergency control policy search calculating, comprising:

Transient stability assessment: check the transient stability that the back electrical network is implemented in thermally-stabilised emergency control measure;

If this moment, electrical network was a transient stability, then described thermally-stabilised emergency control policy as transient stability and heat-staple coordination emergency control policy, calculate termination; If electrical network transient state instability then will be carried out the Transient Stability Control decision search and be calculated on the basis that these control measure are implemented this moment;

Calculate the temporary stability energy index of the optional measure of transient stability emergency control, calculate the transient stability emergency control policy based on this index;

(3) check the thermal stability coordinated electrical network after the measure of transient stability emergency control, if the thermal stability of electrical network has reached the standard of actual needs, then whole coordination emergency control policy calculation process stops; If electrical network still has thermally-stabilised problem, then go to step (1).

2, electric power system transient stability according to claim 1 and thermally-stabilised coordination emergency control method, it is characterized in that the step that the search of transient stability emergency control policy is calculated in the step (2) is as follows: search transient state angle stability emergency control policy, its control strategy is as the transient stability emergency control policy; Then, the search transient voltage is stablized emergency control policy, and its control strategy is to be on the initial value basis with transient state angle stability control measure, coordinates control measure; At last, the search transient frequency is stablized emergency control policy, and its control strategy is that the Transient Stability Control measure that obtains in above two steps is on the initial value basis, coordinates control measure.

3, electric power system transient stability according to claim 1 and 2 and thermally-stabilised coordination emergency control method is characterized in that the computational methods of the overall sensitivity index in the step (1) are as follows:

If L apparatus overload arranged under the forecast failure, so the overall sensitivity index of measure i calculates by the formula following formula:

${\mathrm{PI}}_i=\frac{(\underset{j=1}{\overset{L}{\mathrm{\Σ}}}{S}_{\mathrm{ij}}\·W_j)\×P_{\mathrm{ti}}}{C_i}---\left(1\right)$

Wherein, P _TiFor press temporary stability that the EEAC quantification theory calculates can index (for first iterative process, P _TiValue be set to 1);

S _IjBe the control sensitivity of measure i under the fault for overload equipment j;

C _iControl cost for measure i;

W _jOverload degree for overload equipment.Calculate by following formula:

$W_j={\left(\frac{P_{j,\mathrm{now}}}{P_{j,\mathrm{rate}}}\right)}^2---\left(2\right)$

Wherein, P _{J, now}Actual active power for overload equipment;

P _{J, rate}Specified active power for overload equipment.

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