CN104616214A - Method for evaluating power supply reliability of power distribution network - Google Patents

Abstract

The invention discloses a method for evaluating the power supply reliability of a power distribution network and belongs to the field of power distribution network power supply. The method includes: reading the original data firstly and enumerating corresponding fault events for grid equipment; searching a transformer to obtain power supply interrupted regions caused by faults, conducting fault state simulation and distinguishing the recoverable power supply region from the unrecoverable power supply region; for each fault event of the recoverable power supply region, acquiring the load transferring path through the load transferring path analysis; conducting load flow calculation, if the load flow is overload and the load transferring is not successful, acquiring a new load transferring path; and calculating the reliability index of each load point and the whole power distribution network according to the recoverable power supply region and the unrecoverable power supply region after faults. The method can more accurately and comprehensively evaluate the power supply reliability of the power distribution network so that the level which the urban power grid can reach in the aspect of the power supply ability, the present problems and the development prospect can be deeply realized.

Description

Distribution network reliability appraisal procedure

Technical field

The invention belongs to power distribution network for electrical domain, particularly relate to a kind of distribution network reliability appraisal procedure.

Background technology

Urban distribution network is the important infrastructure in city, is the important substance guarantee of the national economic development and social progress.

In recent years, urban distribution network, through large-scale construction retrofit, has had and has significantly improved in power supply capacity, power supply reliability and power supply quality.Along with China's national economy is fast-developing, electric load increases obviously to be accelerated, and urban distribution network development is faced with new opportunities and new challenge, and mains supply capability evaluation is the necessary component of Electric Power Network Planning.

The domestic research to Electric Power Network Planning appraisement system is at the early-stage, does not also have the achievement of a set of maturation directly to apply.Although external theoretical relative maturity, experience is horn of plenty comparatively, because external power system development stage, developmental tasks and electricity market organizational form and Jiangsu Province's present situation are distinguished comparatively large, is also difficult to direct reference.

The level that can reach in power supply capacity in order to deep understanding urban distribution network and the at present problem such as Problems existing and development prospect, play electrical network better to the supporting role of the national economic development, the Coordinate Development of each electric pressure of abundant reflection urban distribution network, carries out the practical approach of comprehensive assessment in the urgent need to a kind of power supply reliability to existing urban distribution network.

Summary of the invention

Because the above-mentioned defect of prior art, technical matters to be solved by this invention is to provide one more accurately comprehensive distribution network reliability appraisal procedure.

For achieving the above object, the invention provides a kind of distribution network reliability appraisal procedure, it is characterized in that comprising the following steps:

Step one, read in raw data, primitive network structure is preserved;

Step 2, for each grid equipment, enumerate corresponding event of failure and store;

Step 3, transformer to be searched for, obtain the power supply interrupted district caused by fault, carry out malfunction emulation, and distinguish and can recover and irrecoverable power supply area;

Step 4, for each event of failure that can restore electricity in region, ask for load transfer plan path by load transfer plan path analysis;

Step 5, carry out Load flow calculation, if the success of trend nonoverload, load transfer plan, perform step 6, otherwise return and perform step 4 and ask for new load transfer plan path;

Step 6, according to the restored electricity region after fault and irrecoverable power supply area, calculate the reliability index of each load point and whole power distribution network.

Further, further comprising the steps of in described step 4: to restoring electricity, region can not find the path that can recover, and sky is put in the restored electricity region of this fault.

Further, further comprising the steps of after described step 6: to check whether event of failure is enumerated complete, does not complete, then returns execution step 2; Otherwise terminate.

Preferably, reliability index described in six comprises power distribution network normal power supply probability ASAI, distribution network failure frequency SAIFI, distribution network failure SAIDI averaging time, power distribution network expected loss of energy ENSI and load point power failure index;

u _ifor the equivalent annual power off time of load point i, N _ifor the number of users of load point i; I is positive integer;

λ _ifor the equivalent failure rate of load point i;

$\mathrm{SAIDI}=\frac{\underset{i}{\mathrm{\Σ}}{N}_i{U}_i}{\underset{i}{\mathrm{\Σ}}{N}_i};$

ENSI=∑ L _{a (i)}u _i; L _{a (i)}for being connected to the average load of load point i;

Load point power failure index is in the unit time, due to electric network fault cause the frequency of power cut of each load point, power off time and power failure amount.

The invention has the beneficial effects as follows: the reliability assessment that the present invention powers to power distribution network is more accurately comprehensive, the level that the deep enough understanding urban distribution network of energy can reach in power supply capacity and the at present problem such as Problems existing and development prospect, play electrical network better to the supporting role of the national economic development, the Coordinate Development of each electric pressure of urban distribution network can be reflected.

Accompanying drawing explanation

Fig. 1 is the schematic flow sheet of the embodiment of the invention.

Embodiment

Below in conjunction with drawings and Examples, the invention will be further described:

A kind of distribution network reliability appraisal procedure, is characterized in that comprising the following steps:

Step one, read in raw data, primitive network structure is preserved; Raw data comprises: the forced outage rate of equipment, unplanned outage time, planned outage rate, scheduled overhaul time.

Step 2, for each grid equipment, enumerate corresponding event of failure and store;

Step 3, transformer to be searched for, obtain the power supply interrupted district caused by fault, carry out malfunction emulation, and distinguish and can recover and irrecoverable power supply area;

Step 4, for each event of failure that can restore electricity in region, ask for load transfer plan path by load transfer plan path analysis; To restoring electricity, region can not find the path that can recover, and sky is put in the restored electricity region of this fault.

Step 5, carry out Load flow calculation, if the success of trend nonoverload, load transfer plan, perform step 6, otherwise return and perform step 4 and ask for new load transfer plan path;

Step 6, according to the restored electricity region after fault and irrecoverable power supply area, calculate the reliability index of each load point and whole power distribution network, and Output rusults.

It is complete whether step 7, decision event are enumerated, and do not complete, then return execution step 2; Otherwise terminate.

Reliability index described in step 6 comprises power distribution network normal power supply probability ASAI, distribution network failure frequency SAIFI, distribution network failure SAIDI averaging time, power distribution network expected loss of energy ENSI and load point power failure index;

u _ifor the equivalent annual power off time of load point i, N _ifor the number of users of load point i; I is positive integer;

λ _ifor the equivalent failure rate of load point i;

$\mathrm{SAIDI}=\frac{\underset{i}{\mathrm{\Σ}}{N}_i{U}_i}{\underset{i}{\mathrm{\Σ}}{N}_i};$

ENSI=∑ L _{a (i)}u _i; L _{a (i)}for being connected to the average load of load point i;

Load point power failure index is in the unit time, due to electric network fault cause the frequency of power cut of each load point, power off time and power failure amount.

After adopting the present invention, distribution network reliability assessment is more accurate, and can monitor in planning process according to assessment of the present invention, and whether the newly-increased circuit of planning is reasonable, road radius of electricity supply and segments whether in the reasonable scope, to ensure the reliability service level of electrical network.

More than describe preferred embodiment of the present invention in detail.Should be appreciated that those of ordinary skill in the art just design according to the present invention can make many modifications and variations without the need to creative work.Therefore, all technician in the art, all should by the determined protection domain of claims under this invention's idea on the basis of existing technology by the available technical scheme of logical analysis, reasoning, or a limited experiment.

Claims (4)

1. a distribution network reliability appraisal procedure, is characterized in that comprising the following steps:

Step one, read in raw data, primitive network structure is preserved;

Step 2, for each grid equipment, enumerate corresponding event of failure and store;

Step 3, transformer to be searched for, obtain the power supply interrupted district caused by fault, carry out malfunction emulation, and distinguish and can recover and irrecoverable power supply area;

Step 4, for each event of failure that can restore electricity in region, ask for load transfer plan path by load transfer plan path analysis;

Step 5, carry out Load flow calculation, if the success of trend nonoverload, load transfer plan, perform step 6, otherwise return and perform step 4 and ask for new load transfer plan path;

Step 6, according to the restored electricity region after fault and irrecoverable power supply area, calculate the reliability index of each load point and whole power distribution network.

2. distribution network reliability appraisal procedure as claimed in claim 1, is characterized in that: further comprising the steps of in described step 4: to restoring electricity, region can not find the path that can recover, and sky is put in the restored electricity region of this fault.

3. distribution network reliability appraisal procedure as claimed in claim 1, is characterized in that: further comprising the steps of after described step 6: check whether event of failure is enumerated complete, does not complete, then returns execution step 2; Otherwise terminate.

4. distribution network reliability appraisal procedure as claimed in claim 1, is characterized in that: reliability index described in step 6 comprises power distribution network normal power supply probability ASAI, distribution network failure frequency SAIFI, distribution network failure SAIDI averaging time, power distribution network expected loss of energy ENSI and load point power failure index; u _ifor the equivalent annual power off time of load point i, N _ifor the number of users of load point i; I is positive integer;

λ _ifor the equivalent failure rate of load point i;

$\mathrm{SAIDI}=\frac{\underset{i}{\mathrm{\Σ}}{N}_i{U}_i}{\underset{i}{\mathrm{\Σ}}{N}_i};$

ENSI=∑ L _{a (i)}u _i; L _{a (i)}for being connected to the average load of load point i;

Load point power failure index is in the unit time, due to electric network fault cause the frequency of power cut of each load point, power off time and power failure amount.