CN105207201A - Power distribution network feeder circuit optimal segmentation method based on uniform load distribution and biggest power supply reliability - Google Patents

Abstract

The invention relates to a power distribution network feeder circuit optimal segmentation method based on uniform load distribution and biggest power supply reliability, and belongs to the technical field of intelligent power distribution network protection and control. By means of reasonable segmentation of a power distribution network, the efficiency of power distribution automation in practical engineering application can be improved, and the power supply reliability can be improved. The problem that loads are nonuniform in distribution generally exists in a power distribution network feeder circuit, due to the fact that segmentation is directly conducted without calculation normally during practical engineering construction, a great distance exists between the effect achieved in practical segmentation and an expected effect. According to the power distribution network feeder circuit optimal segmentation method based on the uniform load distribution and the biggest power supply reliability, for the problem that on-site loads are nonuniform in distribution, the power supply reliability serves as the basis, the maximum number of segments is obtained according to the maximum load, the reliability of each number of segmentation under the optimal segment is calculated from the second segmentation to the maximum number of segmentation, comparison is conducted on a reliability curve when the loads are uniform in distribution, the optimizing segmentation and the optimal segmentation under all segmentation modes are achieved, and the number of segmentation and segmentation points are determined finally according to practical situations such as engineering cost.

Description

A kind of power distribution network feeder line optimizing fractional method of the maximum power supply reliability that distributes based on uniform load

Technical field

The present invention is a kind of power distribution network feeder line optimizing fractional method of the maximum power supply reliability that distributes based on uniform load, belongs to intelligent distribution network protection and control technical field.

Technical background

Distribution system belongs to electric power system end, is the link be directly connected with user facility.Once distribution system breaks down or carry out overhauling, testing, the interruption that system of users will be caused to power, affects power supply reliability.Along with socioeconomic development, the raising of living standards of the people and the extensive use of electrical equipment, the requirement of user to power system power supply reliability is also more and more higher, and distribution Power System Reliability, as an important component part of power system reliability, more and more causes the attention of people.

The effect that in power distribution automation, feeder automation improves power supply reliability and the quantity of block switch of installing on feeder line have substantial connection.Current power distribution network switching optimization is by cost---based on performance analysis principle, relate to the many factors such as the investment of switchgear, operation and maintenance cost and loss of outage.There is the problem of equitable subsection in power distribution automation, the problem that power distribution network feeder line physical presence power load distributing is uneven in practical implementation, usually do not calculated and directly segmentation during engineering construction.Feeder line gradation study based on power supply reliability is less, and distribution planning, rectification need to consider to distribute rationally by the power distribution network block switch improved for the purpose of power supply reliability.

Summary of the invention

The object of this invention is to provide a kind of power distribution network feeder line optimizing fractional method of the maximum power supply reliability that distributes based on uniform load, in order to solve the problem.

Technical scheme of the present invention is: a kind of power distribution network feeder line optimizing fractional method of the maximum power supply reliability that distributes based on uniform load, when power load distributing is uneven, according to peak load, obtain maximum segment number, when calculating from two-section to maximum segment number, reliability in the best segmentation situation of each segments, reliability curve time even with power load distributing takes absolute value after doing difference, according to reliability difference order from low to high, arrangement segments, finally according to actual conditions determination segments such as engineering costs.

Concrete steps are:

The first step, utilize intelligent distribution network central database, transfer each branch's load p (i) of circuit and point number i.For bar same on basic routing line, multiple branches with tower, be summed up as a branch.

Second step, ask for total load P, the branch a at maximum branch load M and place thereof.

$P=\underset{1}{\overset{i}{\Σ}}p\left(x\right)---\left(1\right)$

3rd step, according to maximum branch load determination maximum segment number n, when n is not integer, round numbers backward, is designated as c.

Wherein

$n=\frac{P}{M}---\left(2\right)$

4th step, segmentation from n=2, determine n=c successively.When there being multiple segmented mode under certain segments, get the situation that di is minimum, record segmentation method.Wherein

Work as P _i> P _i+1time, $d_i=\frac{P_i}{P_{i+1}}---\left(3\right)$

Work as P _i< P _i+1time, $d_i=\frac{P_{i+1}}{P_i}---\left(4\right)$

5th step, drafting reliability curve, and contrast.The reliability curve carrying out segmentation under load uneven distribution and load being uniformly distributed two kinds of situations is plotted in the same window, does to differ from and the Di that takes absolute value at each waypoint place

D _i=load is uniformly distributed-uneven distribution (5)

According to the order sequence that Di is ascending, a sequence of optimal segmentation number, then determine most equitable subsection number according to engineering cost, the most excellent actual conditions in installation site.

The invention has the beneficial effects as follows: along with economic development, more and more higher to the requirement of power supply reliability, in Practical Project, distribution network line power load distributing is uneven simultaneously.For the problems referred to above, segmentation is carried out to the load uneven distribution distribution network feeder based on reliability there is actual application value, be convenient to distribution network planning and rectification.

Accompanying drawing explanation

Fig. 1 is typical " handing in hand " looped network electric line model of power distribution network;

Fig. 2 is segmentation on B bus in embodiment, when breaking down in load maximum section, and the comparison diagram when reliability curve that different segments is corresponding and load are uniformly distributed.

Embodiment

Below in conjunction with drawings and Examples, the present invention is further elaborated.

A kind of power distribution network feeder line optimizing fractional method of the maximum power supply reliability that distributes based on uniform load, when power load distributing is uneven, according to peak load, obtain maximum segment number, when calculating from two-section to maximum segment number, the reliability in the best segmentation situation of each segments, reliability curve time even with power load distributing takes absolute value after doing difference, according to reliability difference order from low to high, arrangement segments, finally according to actual conditions determination segments such as engineering costs.

Concrete steps are:

The first step, utilize intelligent distribution network central database, transfer each branch's load p (i) of circuit and point number i.For bar same on basic routing line, multiple branches with tower, be summed up as a branch.

Second step, ask for total load P, the branch a at maximum branch load M and place thereof.

$P=\underset{1}{\overset{i}{\&Sigma;}}p\left(x\right)---\left(1\right)$

3rd step, according to maximum branch load determination maximum segment number n, when n is not integer, round numbers backward, is designated as c.

Wherein

$n=\frac{P}{M}---\left(2\right)$

4th step, segmentation from n=2, determine n=c successively.When there being multiple segmented mode under certain segments, get the situation that di is minimum, record segmentation method.Wherein

Work as P _i> P _i+1time, $d_i=\frac{P_i}{P_{i+1}}---\left(3\right)$

Work as P _i< P _i+1time, $d_i=\frac{P_{i+1}}{P_i}---\left(4\right)$

5th step, drafting reliability curve, and contrast.The reliability curve carrying out segmentation under load uneven distribution and load being uniformly distributed two kinds of situations is plotted in the same window, does to differ from and the Di that takes absolute value at each waypoint place

D _i=load is uniformly distributed-uneven distribution (5)

According to the order sequence that Di is ascending, a sequence of optimal segmentation number, then determine most equitable subsection number according to engineering cost, the most excellent actual conditions in installation site.

Embodiment 1:

As shown in Figure 1, A, B two sections of buses are connected by often driving interconnection switch typical " handing in hand " looped network electric line model of power distribution network, and when one section of bus breaks down, interconnection switch energy automatic closing realizes turning power supply.The place that fault rate is the highest is maximum branch.

1, utilize intelligent distribution network central database, transfer B bus Shang Ge branch's load p (i) and point number i, and calculate total load according to the formula (1) in specification.

$P=\underset{1}{\overset{22}{\&Sigma;}}p\left(x\right)=8890$

2, maximum segment number c is obtained according to the formula (2) in specification.

c＝5

3, segmentation from n=2, determines n=c successively.When there being multiple segmented mode under certain segments, according to formula (3) (4), get the situation that di is minimum, record segmentation method.

During two-section, waypoint is after the 9th article of branch;

During three segmentations, waypoint is after the 8th, 15 article of branch;

During four segmentations, waypoint is after the 7th, 8,13 article of branch;

During five segmentations, waypoint is after the 7th, 8,11,18 article of branch.

4, draw reliability curve, and contrast.The reliability curve carrying out segmentation under load uneven distribution and load being uniformly distributed two kinds of situations is plotted in the same window, makes difference Di at each waypoint place

D _i=load is uniformly distributed-uneven distribution (5)

According to the order sequence that Di is ascending, a sequence of optimal segmentation number, then determine most equitable subsection number according to engineering cost, the most excellent actual conditions in installation site.

As can be seen from Fig. 2 and table, optimal segmentation sequence is 5,2,3,4.

Segments	2	3	4	5
					D i	0.0843	0.0859	0.1012	0.0224

Claims (2)

1. the power distribution network feeder line optimizing fractional method of the maximum power supply reliability that to distribute based on uniform load, it is characterized in that: when power load distributing is uneven, according to peak load, obtain maximum segment number, when calculating from two-section to maximum segment number, reliability in the best segmentation situation of each segments, reliability curve time even with power load distributing takes absolute value after doing difference, according to reliability difference order from low to high, arrangement segments, finally according to actual conditions determination segments such as engineering costs.

2. the power distribution network feeder line optimizing fractional method of the maximum power supply reliability that distributes based on uniform load according to claim 1, is characterized in that concrete steps are as follows:

The first step, utilize intelligent distribution network central database, transfer each branch's load p (i) of circuit and point number i, for bar same on basic routing line, multiple branches with tower, be summed up as a branch;

Second step, ask for total load P, the branch a at maximum branch load M and place thereof;

$P=\underset{1}{\overset{i}{\&Sigma;}}p\left(x\right)---\left(1\right)$

3rd step, according to maximum branch load determination maximum segment number n, when n is not integer, round numbers backward, is designated as c, wherein:

$n=\frac{P}{M}---\left(2\right)$

4th step, segmentation from n=2, determine n=c successively, when there being multiple segmented mode under certain segments, gets the situation that di is minimum, record segmentation method, wherein:

Work as P _i> P _i+1time, $d_i=\frac{P_i}{P_{i+1}}---\left(3\right)$

Work as P _i< P _i+1time, $d_i=\frac{P_{i+1}}{P_i}---\left(4\right)$

5th step, drafting reliability curve, and contrast, the reliability curve carrying out segmentation under load uneven distribution and load being uniformly distributed two kinds of situations is plotted in the same window, makes difference Di at each waypoint place

D _i=load is uniformly distributed-uneven distribution (5)

According to the order sequence that Di is ascending, a sequence of optimal segmentation number, then determine most equitable subsection number according to engineering cost, the most excellent actual conditions in installation site.