CN105514983A - Load model construction method based on statistical synthesis method and fault simulation method - Google Patents

Abstract

The invention provides a load model construction method based on a statistical synthesis method and a fault simulation method. The load model construction method comprises the following steps: a load model for loading low voltage multistage release characteristic is constructed; the movement levels of a low voltage trip switch are divided; movement voltage released by each level low voltage and average delay time constant are determined; and load proportionality coefficient released by each level low voltage is determined. According to the invention, the load low voltage multistage release characteristic can be accurately simulated, and the reliability of the electric power system simulating calculation can be improved.

Description

The load model construction method of a kind of Corpus--based Method synthesis and fault fitting method

Technical field

The present invention relates to Simulating technique in Electric Power System, be specifically related to the load model construction method of a kind of Corpus--based Method synthesis and fault fitting method.

Background technology

At present, still do not have the power system load modeling method of strict theoretical foundation both at home and abroad, in actual production runs, the model that staff only can adopt pure static load model or static load to combine with induction-motor load, be difficult to the dynamic process of accurate simulation load, cause electric system simulation, stability analysis and differentiation precision not enough, the load model that U.S. WECC newly adopted in 2012 is too complicated, affects computational efficiency and practicality.In addition, parameter identification load modeling method based on identification theory and the weighted equivalent load modeling method based on investigation statistics are also study more method, but the problem of parameter identification method is that model parameter physical significance is indefinite, and the load model generated can only correspond to by the actual measurement sample of identification in principle, it being applied to multilayer output feedback network is one of main contents of grid simulation calculating, the limit transmitted power of circuit and the critical clearing time of fault can be understood by multilayer output feedback network, and operation and the planning of electrical network is instructed with this, and as emulating one of main model, load model is great on simulation result impact.Consider low-voltage release in the characteristic parameter of load low-voltage multistage release characteristics operation voltage and average delay time constant determined by low pressure trip switch definite value, can by adopting in individual equipment type static load active power to be the static load low-voltage release movement voltage of weighted factor to load model relative to the per unit value of the total static load active power of node, low-voltage release constant average delay time carries out polymerization and calculates, and the multistage releasing ratio of load low-voltage is complete because the measured data of each load station after generation disturbance accident is difficult to collection, be difficult to be obtained by statistics.

Summary of the invention

In order to overcome above-mentioned the deficiencies in the prior art, the invention provides the load model construction method of a kind of Corpus--based Method synthesis and fault fitting method, realizing the multistage release characteristics of low-voltage of simulating load more exactly, improving the confidence level that electric system simulation calculates.

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

The invention provides the load model construction method of a kind of Corpus--based Method synthesis and fault fitting method, said method comprising the steps of:

Step 1: build the load model considering the multistage release characteristics of load low-voltage;

Step 2: the action rank dividing low-voltage trip switch;

Step 3: determine every grade of low-voltage release movement voltage and average delay time constant;

Step 4: determine every grade of low-voltage release load proportion coefficient.

In described step 1, on the basis of SLM load model, introducing the multistage release characteristic parameter of load low-voltage for characterizing the multistage release characteristics of load low-voltage, building the load model considering the multistage release characteristics of load low-voltage based on load low-voltage dropout anti-time limit characteristic.

In described step 2, according to the operation voltage U of low-voltage trip switch _cbe following three classes by the action partition of the level of low-voltage trip switch:

1) U is worked as _c< 0.6U _ntime, the action rank of low-voltage trip switch is the first order;

2) 0.6U is worked as _n≤ U _c< 0.75U _ntime, the action rank of low-voltage trip switch is the second level;

3) 0.75U is worked as _n≤ U _ctime, the action rank of low-voltage trip switch is the third level;

Wherein, U _nrepresent the rated voltage of low-voltage trip switch.

In described step 3, Corpus--based Method synthesis determine every grade of low-voltage release movement voltage and average delay time constant.

Described step 3 comprises:

If n is the 10kV/6kV feeder line outlet number comprised in 220kV load website, P _i0be the initial active power of load of i-th 10kV/6kV feeder line, i=1,2 ..., n; Adopt the initial active-power P of load of wall scroll 10kV/6kV feeder line _i0relative to total load active power in 220kV load website per unit value be that weighted factor is to every grade of low-voltage release movement voltage U _cjand every grade of low-voltage release constant T average delay time _cjcarry out comprehensive, have:

$U_{cj}=\frac{\underset{i=1}{\overset{n}{\&Sigma;}}(P_{i0}\&times;U_{cij})}{\underset{i=1}{\overset{n}{\&Sigma;}}{P}_{i0}}---\left(1\right)$

$T_{cj}=\frac{\underset{i=1}{\overset{n}{\&Sigma;}}(P_{i0}\&times;T_{cij})}{\underset{i=1}{\overset{n}{\&Sigma;}}{P}_{i0}}---\left(2\right)$

Wherein, U _cijand T _cijrepresent jth level low-voltage release movement voltage and the low-voltage hang-over delay constant of low-voltage trip switch on i-th 10kV/6kV feeder line respectively, j=1,2,3.

In described step 4, determine every grade of low-voltage release load proportion coefficient according to fault fitting method.

If altogether there are 3 accidents in power train, k _c1represent the 1st grade of low-voltage release load proportion coefficient, k _c2represent the 2nd grade of low-voltage release load proportion coefficient, k _c3represent 3rd level low-voltage release load proportion coefficient, described step 4 comprises:

Step 4-1: setting wherein, P _loss1the load of losing when representing that the 1st accident occurs in electric power system, P _s1there is the total burden with power before the 1st accident in expression electric power system;

Step 4-2: determine operational mode when the 1st accident occur in electric power system and corresponding accident analog form;

Step 4-3: carry out electric power system there is the 1st accident after simulation calculation;

Step 4-4: after the 1st accident that low-voltage that contrast simulation calculates release load power and actual measurement obtain, whether low-voltage to discharge load sum consistent, if inconsistent, then adjusts k _c1, k _c2, k _c3, and return step 4-3, if consistent, perform step 4-5;

Step 4-5: determine operational mode when the 2nd accident occur in electric power system and corresponding accident analog form;

Step 4-6: carry out electric power system there is the 2nd accident after simulation calculation;

Step 4-7: after the 2nd accident that low-voltage that contrast simulation calculates release load power and actual measurement obtain, whether low-voltage to discharge load sum consistent, if inconsistent, then adjusts k _c1, k _c2, k _c3, and return step 4-3, if consistent, perform step 4-8;

Step 4-9: determine operational mode when the 3rd accident occur in electric power system and corresponding accident analog form;

Step 4-10: carry out electric power system there is the 3rd accident after simulation calculation;

Step 4-11: after the 3rd accident that low-voltage that contrast simulation calculates release load power and actual measurement obtain, whether low-voltage to discharge load sum consistent, if inconsistent, then adjusts k _c1, k _c2, k _c3, and return step 4-3, if consistent, export k _c1, k _c2, k _c3.

Compared with immediate prior art, technical scheme provided by the invention has following beneficial effect:

1) collection is difficult to for some power grid user side load low-voltage release data complete, first the present invention builds the load model considering the multistage release characteristics of load low-voltage, divide action rank then under voltage trip switch, the operation voltage of every grade of low-voltage release in the multistage releasing theory of last Corpus--based Method synthesis determination load low-voltage and average delay time constant, and based on the proportionality coefficient of every grade of low-voltage release in the multistage releasing theory of fault fitting method determination load low-voltage;

2) based on the actual load amount percentage of grid loss after disturbance accident, by accident mode simulation calculation low-voltage multistage release load proportion coefficient, and by different disturbance accident iterated revision three coefficients, make the error between simulation calculation load loss amount and reality minimum, improve the confidence level that electric system simulation calculates.

Accompanying drawing explanation

Fig. 1 is the load model construction method flow chart of Corpus--based Method synthesis and fault fitting method in the embodiment of the present invention;

Fig. 2 is the load model structure chart considering the multistage release characteristics of load low-voltage in the embodiment of the present invention.

Embodiment

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

The invention provides the load model construction method of a kind of Corpus--based Method synthesis and fault fitting method, as Fig. 1, said method comprising the steps of:

Step 1: build the load model considering the multistage release characteristics of load low-voltage;

Step 2: the action rank dividing low-voltage trip switch;

Step 3: determine every grade of low-voltage release movement voltage and average delay time constant;

Step 4: determine every grade of low-voltage release load proportion coefficient.

In described step 1, as Fig. 2, (integrated load model of distribution network is namely considered at SLM load model, synthesisloadmodel) on basis, introducing the multistage release characteristic parameter of load low-voltage for characterizing the multistage release characteristics of load low-voltage, building the load model considering the multistage release characteristics of load low-voltage based on load low-voltage dropout anti-time limit characteristic.Wherein, U _c1be the 1st stage load low pressure release movement voltage, T _c1be the 1st stage load low-voltage release constant average delay time, K _c1it is the 1st stage load low-voltage release load proportion coefficient; U _c2be the 2nd stage load low pressure release movement voltage, T _c2be the 2nd stage load low-voltage release constant average delay time, K _c2it is the 2nd stage load low-voltage release load proportion coefficient; U _c3for 3rd level load low pressure release movement voltage, T _c3for 3rd level load low-voltage release constant average delay time, K _c3for 3rd level load low-voltage release load proportion coefficient.

In described step 2, according to the operation voltage U of low-voltage trip switch _cbe following three classes by the action partition of the level of low-voltage trip switch:

1) U is worked as _c< 0.6U _ntime, the action rank of low-voltage trip switch is the first order;

2) 0.6U is worked as _n≤ U _c< 0.75U _ntime, the action rank of low-voltage trip switch is the second level;

3) 0.75U is worked as _n≤ U _ctime, the action rank of low-voltage trip switch is the third level;

Wherein, U _nrepresent the rated voltage of low-voltage trip switch.

In described step 3, Corpus--based Method synthesis determine every grade of low-voltage release movement voltage and average delay time constant.

Described step 3 comprises:

If n is the 10kV/6kV feeder line outlet number comprised in 220kV load website, P _i0be the initial active power of load of i-th 10kV/6kV feeder line, i=1,2 ..., n; Adopt the initial active-power P of load of wall scroll 10kV/6kV feeder line _i0relative to total load active power in 220kV load website per unit value be that weighted factor is to every grade of low-voltage release movement voltage U _cjand every grade of low-voltage release constant T average delay time _cjcarry out comprehensive, have:

$U_{cj}=\frac{\underset{i=1}{\overset{n}{\&Sigma;}}(P_{i0}\&times;U_{cij})}{\underset{i=1}{\overset{n}{\&Sigma;}}{P}_{i0}}---\left(1\right)$

$T_{cj}=\frac{\underset{i=1}{\overset{n}{\&Sigma;}}(P_{i0}\&times;T_{cij})}{\underset{i=1}{\overset{n}{\&Sigma;}}{P}_{i0}}---\left(2\right)$

Wherein, U _cijand T _cijrepresent jth level low-voltage release movement voltage and the low-voltage hang-over delay constant of low-voltage trip switch on i-th 10kV/6kV feeder line respectively, j=1,2,3.

In described step 4, determine every grade of low-voltage release load proportion coefficient according to fault fitting method.

If altogether there are 3 accidents in power train, k _c1represent the 1st grade of low-voltage release load proportion coefficient, k _c2represent the 2nd grade of low-voltage release load proportion coefficient, k _c3represent 3rd level low-voltage release load proportion coefficient, described step 4 comprises:

Step 4-1: setting wherein, P _loss1the load of losing when representing that the 1st accident occurs in electric power system, P _s1there is the total burden with power before the 1st accident in expression electric power system;

Step 4-2: determine operational mode when the 1st accident occur in electric power system and corresponding accident analog form;

Step 4-3: carry out electric power system there is the 1st accident after simulation calculation;

Step 4-4: after the 1st accident that low-voltage that contrast simulation calculates release load power and actual measurement obtain, whether low-voltage to discharge load sum consistent, if inconsistent, then adjusts k _c1, k _c2, k _c3, and return step 4-3, if consistent, perform step 4-5;

Step 4-5: determine operational mode when the 2nd accident occur in electric power system and corresponding accident analog form;

Step 4-6: carry out electric power system there is the 2nd accident after simulation calculation;

Step 4-7: after the 2nd accident that low-voltage that contrast simulation calculates release load power and actual measurement obtain, whether low-voltage to discharge load sum consistent, if inconsistent, then adjusts k _c1, k _c2, k _c3, and return step 4-3, if consistent, perform step 4-8;

Step 4-9: determine operational mode when the 3rd accident occur in electric power system and corresponding accident analog form;

Step 4-10: carry out electric power system there is the 3rd accident after simulation calculation;

Step 4-11: after the 3rd accident that low-voltage that contrast simulation calculates release load power and actual measurement obtain, whether low-voltage to discharge load sum consistent, if inconsistent, then adjusts k _c1, k _c2, k _c3, and return step 4-3, if consistent, export k _c1, k _c2, k _c3.

Embodiment

For verifying the validity of the load parameter computational methods of the multistage release characteristics of consideration load low-voltage that this problem proposes, below by outer two factories busbar fault simulation on March 7th, 2009, check the validity of the multistage release characteristics parameter of load low pressure adopting the present invention to obtain.

The load station point load low pressure multistage release characteristics parameter that employing the present invention obtains District of Shanghai is as shown in table 1.

Table 1

Round	U c(％U n)	T c(ms)	k c
				1	0.5	40	5％
2	0.65	100	8％
				3	0.80	280	11％

On March 7th, 2009; bridge turns round and look in line 5031 switch process; field service personnel unlocks closes 50311 plug-in strips by mistake; cause the female three-phase ground short circuit of outer two factory 500kVI; the female bus bar differential prptection operation of I, tripping No. 5 main transformer 5011 switches, high line 5021 switch, District of Shanghai low pressure release guard action; loss load 143.5 ten thousand kilowatts, accounts for 10% of Shanghai Power Network total load.

The load low pressure multistage release characteristics parameter of employing table 1 carries out the simulation calculation of above-mentioned fault, and simulation result shows District of Shanghai low pressure release guard action, 10% of low pressure release Shanghai Power Network total load.The load low pressure multistage release characteristics parameter that this explanation method generates can describe the multistage release characteristics of load low pressure preferably, system performance during fault post-simulation is calculated is closer to real system action, improve the confidence level of Simulation Analysis, for electric power system work out the operation of science, control program provides guarantee.

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; those of ordinary skill in the field still can modify to the specific embodiment of the present invention with reference to above-described embodiment or equivalent replacement; these do not depart from any amendment of spirit and scope of the invention or equivalent replacement, are all applying within the claims of the present invention awaited the reply.

Claims (7)

1. a load model construction method for Corpus--based Method synthesis and fault fitting method, is characterized in that: said method comprising the steps of:

Step 1: build the load model considering the multistage release characteristics of load low-voltage;

Step 2: the action rank dividing low-voltage trip switch;

Step 3: determine every grade of low-voltage release movement voltage and average delay time constant;

Step 4: determine every grade of low-voltage release load proportion coefficient.

2. the load model construction method of Corpus--based Method synthesis according to claim 1 and fault fitting method, it is characterized in that: in described step 1, on the basis of SLM load model, introducing the multistage release characteristic parameter of load low-voltage for characterizing the multistage release characteristics of load low-voltage, building the load model considering the multistage release characteristics of load low-voltage based on load low-voltage dropout anti-time limit characteristic.

3. the load model construction method of Corpus--based Method synthesis according to claim 1 and fault fitting method, is characterized in that: in described step 2, according to the operation voltage U of low-voltage trip switch _cbe following three classes by the action partition of the level of low-voltage trip switch:

1) U is worked as _c< 0.6U _ntime, the action rank of low-voltage trip switch is the first order;

2) 0.6U is worked as _n≤ U _c< 0.75U _ntime, the action rank of low-voltage trip switch is the second level;

3) 0.75U is worked as _n≤ U _ctime, the action rank of low-voltage trip switch is the third level;

Wherein, U _nrepresent the rated voltage of low-voltage trip switch.

4. the load model construction method of Corpus--based Method synthesis according to claim 1 and fault fitting method, is characterized in that: in described step 3, Corpus--based Method synthesis determine every grade of low-voltage release movement voltage and average delay time constant.

5. the load model construction method of Corpus--based Method synthesis according to claim 4 and fault fitting method, is characterized in that: described step 3 comprises:

If n is the 10kV/6kV feeder line outlet number comprised in 220kV load website, P _i0be the initial active power of load of i-th 10kV/6kV feeder line, i=1,2 ..., n; Adopt the initial active-power P of load of wall scroll 10kV/6kV feeder line _i0relative to total load active power in 220kV load website per unit value be that weighted factor is to every grade of low-voltage release movement voltage U _cjand every grade of low-voltage release constant T average delay time _cjcarry out comprehensive, have:

$U_{cj}=\frac{\underset{i=1}{\overset{n}{\&Sigma;}}(P_{i0}\&times;U_{cij})}{\underset{i=1}{\overset{n}{\&Sigma;}}{P}_{i0}}---\left(1\right)$

$T_{cj}=\frac{\underset{i=1}{\overset{n}{\&Sigma;}}\left(P_{i0}\&times;T_{cij}\right)}{\underset{i=1}{\overset{n}{\&Sigma;}}{P}_{i0}}---\left(2\right)$

Wherein, U _cijand T _cijrepresent jth level low-voltage release movement voltage and the low-voltage hang-over delay constant of low-voltage trip switch on i-th 10kV/6kV feeder line respectively, j=1,2,3.

6. the load model construction method of Corpus--based Method synthesis according to claim 1 and fault fitting method, is characterized in that: in described step 4, determines every grade of low-voltage release load proportion coefficient according to fault fitting method.

7. the load model construction method of Corpus--based Method synthesis according to claim 6 and fault fitting method, is characterized in that: establish power train 3 accidents altogether to occur, k _c1represent the 1st grade of low-voltage release load proportion coefficient, k _c2represent the 2nd grade of low-voltage release load proportion coefficient, k _c3represent 3rd level low-voltage release load proportion coefficient, described step 4 comprises:

Step 4-1: setting wherein, P _loss1the load of losing when representing that the 1st accident occurs in electric power system, P _s1there is the total burden with power before the 1st accident in expression electric power system;

Step 4-2: determine operational mode when the 1st accident occur in electric power system and corresponding accident analog form;

Step 4-3: carry out electric power system there is the 1st accident after simulation calculation;

Step 4-4: after the 1st accident that low-voltage that contrast simulation calculates release load power and actual measurement obtain, whether low-voltage to discharge load sum consistent, if inconsistent, then adjusts k _c1, k _c2, k _c3, and return step 4-3, if consistent, perform step 4-5;

Step 4-5: determine operational mode when the 2nd accident occur in electric power system and corresponding accident analog form;

Step 4-6: carry out electric power system there is the 2nd accident after simulation calculation;

Step 4-7: after the 2nd accident that low-voltage that contrast simulation calculates release load power and actual measurement obtain, whether low-voltage to discharge load sum consistent, if inconsistent, then adjusts k _c1, k _c2, k _c3, and return step 4-3, if consistent, perform step 4-8;

Step 4-9: determine operational mode when the 3rd accident occur in electric power system and corresponding accident analog form;

Step 4-10: carry out electric power system there is the 3rd accident after simulation calculation;

Step 4-11: after the 3rd accident that low-voltage that contrast simulation calculates release load power and actual measurement obtain, whether low-voltage to discharge load sum consistent, if inconsistent, then adjusts k _c1, k _c2, k _c3, and return step 4-3, if consistent, export k _c1, k _c2, k _c3.