CN104680253A - Reliability and economy-coordinated optimization method of power distribution network planning and investment - Google Patents

Abstract

The invention discloses a reliability and economy-coordinated optimization method of power distribution network planning and investment. The method firstly determines unit load reliability improving costs and unit load increasing costs, then determines investment benefits of corresponding sub-regions, and finally establishes a power distribution network investment optimization distribution model with the goal of maximizing the investment benefits. The method comprises the following steps: (1) estimation of investment costs: estimating a reliability improving investment cost and a unit load increasing cost and an overall investment cost; (2) estimation of investment benefits: proposing the concept of a ratio of output value to unit electric energy consumption, evaluating the economic benefits generated by unit electrical energy in this region; (3) estimation of target reasonableness: determining the reasonableness of annual target power supply reliability setting according to the relationship between the total investment cost and the budget; (4) establishment of a reliability and economy-coordinated investment optimization model: taking different types of power supply loads in all regions as optimization variables, taking the maximum investment benefits of the whole region as the optimization target, and taking the investment budget as the constraint.

Description

The distribution network planning coordinated mutually based on reliability and economy invests optimization method

Technical field

The present invention relates to a kind of distribution network planning coordinated mutually based on reliability and economy and invest optimization method, belong to power planning technical field.

Background technology

Power distribution network is the important component part of electrical network, and directly towards power consumer, being the key link ensureing that electric power " is come to down, be can use ", is the important infrastructure improved People's livelihood.Still have area power grid still exist reduce radius of electricity supply, improve customer power supply reliability and plant factor low, rural area low-voltage and high voltage exist simultaneously, distribution transforming at ordinary times underloading and Spring Festival transship between contradiction.Technically, the grid-connected research work of wind-powered electricity generation, small power station, distributed energy is delayed, is difficult to the coordinated development of scientific guidance net source; Distribution network reliability calculates and development diagnostic analysis is not yet in full swing, the distribution of distribution network planning goal setting and investment amount still relies on experience, many areas also exist planning unreal, lead unclear, project investment is unreasonable, the situation that even can hardly be explained, also there is the qualitative analysis stage in whole power distribution network research.In management, the structure of some areas to power distribution network long-range objectives rack is paid little attention to, and typical powering mode and Standardization Construction are carried out not yet comprehensively, and industry expands and user accesses engineering not yet specification, there is low level and repeatedly transforms and the problem such as duplicate construction; Distribution network planning leading action is not still given prominence to, poor to planning guide.In people power, relevant institutes generally lacks power distribution network researchist, and the talent team is versus young also, lacks experience, very limited to the distribution network technology supporting role of this province.Support in power distribution network informationization, lack distribution network planning support technology platform, mass data intersperses among in the professional system such as PMS, SCADA, marketing SG186, and Statistical Criteria differs, and data management granularity, frequency require inconsistent, be difficult to adapt to distribution network planning need of work.

Summary of the invention

The object of the invention is, in order to solve distribution network planning Problems existing, the present invention proposes a kind of distribution network planning coordinated mutually based on reliability and economy and invests optimization method.

Technical scheme of the present invention is, the inventive method, using the harmony between reliability and economy as the main points realizing differentiation planning and design, is coordinated mutually from public resource and user resources, three aspects such as growth requirement and the investment ability is coordinated mutually, rural area electric pressure coordinated development is carried out investment and distribute rationally.

The present invention increases specific load cost under first promoting cost and setting reliability level by data fitting determination specific load reliability; Then formed and loss of outage by the user of dissimilar subregion, determine the returns of investment of respective partition; Finally be target to the maximum with returns of investment, set up power distribution network investment model of optimizing allocation, realize the optimum allocation of planning capital investment shares, improve the efficiency of the operation of capital.

The present invention comprises following step:

The first step, electric grid investment costimating, estimates reliability and promotes cost of investment, increase specific load cost, and comprehensive method of investment cost.

According to load increment and the reliability winding level in planning year, can estimate the investment cost of this area, the present invention need calculate the investment value of three aspects, and namely reliability promotes cost of investment, increase specific load cost, consider the cost of investment of load growth and electric network reliability.Between three parameters, relations and differences is stated as follows:

Reliability promotes cost estimation

By many ground electrical network characteristic of sampling, get specific load investment and reliability index data relationship, polynomial fitting method can draw not to be considered in load variations situation, and promote the variation relation between cost of investment needed for power supply reliability and reliability index, its form is:

$C_{\mathrm{rui}}=a(r_{\mathrm{ei}}^3-r_{\mathrm{ci}}^3)-b(r_{\mathrm{ei}}^2-r_{\mathrm{ci}}^2)-c(r_{\mathrm{ei}}^1-r_{\mathrm{ci}}^1)-d---\left(1\right)$

In formula: C _ruifor region i specific load reliability promotes cost; r _eiand r _cibe respectively region i target year and present situation year power supply reliability level.

According to formula (1), power supply area i reliability can be obtained and promote required cost C _ri, shown in (2):

C _ri＝L _ciC _rui(2)

In formula: L _cifor power supply area i present situation year load level.

Increase specific load cost estimation

By many ground electrical network characteristic of sampling, get specific load investment and reliability index data relationship, polynomial fitting method can draw not to be considered in load variations situation, promote the variation relation between cost of investment needed for power supply reliability and reliability index, its form is such as formula (3):

$C_{\mathrm{lui}}=a^{\′}{r}_{\mathrm{ei}}^3+b^{\′}{r}_{\mathrm{ei}}^2+c^{\′}{r}_{\mathrm{ei}}^1+d^{\′}---\left(3\right)$

According to formula (3), cost C needed for power supply area i load growth can be obtained _li, shown in (4):

C _li＝(L _ei-L _ci)C _lui(4)

In formula: L _eifor region i target year load level.

Consider the cost of investment estimation of load growth and electric network reliability

Under the condition that known each power supply area reliability promotes cost and load growth cost, can estimate and invest total expenses with specification needed for whole power supply area, shown in (5).

C＝∑ _i∈G(C _ri+C _li) (5)

In formula: C is whole power supply area required investment total expenses; G is the set that power supply area subregion is formed.

Second step, estimation of investment efficiency, proposes the concept of comprehensive electrogenesis ratio, weighs the economic benefit that this area's unit of electrical energy produces.

The annual gross domestic product (GDP) of electrogenesis ratio and somewhere and the ratio consuming electric flux, describe the economic benefit that the annual unit of electrical energy in a certain area is created.The present invention proposes the concept of comprehensive electrogenesis ratio, with clear and definite physical meaning, in conjunction with the industrial structure feature of different regions, and the comprehensive economic benefit weighed the annual per unit electric energy in this area and can produce.Adopt comprehensive electrogenesis to carry out estimation loss of outage OC (outage cost) than method, computing formula is such as formula (6):

OC＝AOC×L×K (6)

In formula: K is comprehensive electrogenesis ratio, AOC (average outage time) is power off time per family, and L is load level.

Comprehensive electrogenesis to be weighted by all types of user electrogenesis ratio than K and to form, and computing method are provided by formula (7):

K＝k _j×d _j+k _c1×d _c1+k _c2×d _c2+k _c3×d _c3+k _x×d _x(7)

Wherein: k _j, k _c1, k _c2, k _c3, k _xbe respectively the electrogenesis ratio of resident, trade financing, industry, public utilities and agricultural; d _j, d _c1, d _c2, d _c3, d _xbe respectively the electricity consumption ratio of resident, trade financing, industry, public utilities and agricultural.

Returns of investment index calculate

Get that specific investment increases delivery, specific investment increases and reduce power off time, low-voltage number of users as the reference index of regional investment benefit for load, policy guidance, social loss of outage, specific investment.

3rd step, target reasonable evaluation, according to the rationality that the relation determination target year power supply reliability between investment total expenses and budget is arranged.

According to the relation estimated between the investment total expenses C of gained and investment budgey Y, the rationality of target year power supply reliability setting can be determined:

1) work as Y=C, show that budget conforms to required investment cost, power supply area can reach the reliability objectives of setting, distributes the investment of each subregion by formula (5-5);

2) Y<C is worked as, show budgetary shortfall, target year reliability objectives need be reset, specifically increase the mode of step-length by setting between rci and rei, draw the relation curve between reliability and investment cost, choose a point nearest with budget as the reliability objectives under this budget condition.

3) Y>C is worked as, show that budget is comparatively sufficient, by optimization of investment allocative decision, under ensureing that each subregion reaches the prerequisite of setting reliability objectives, consider that load density, GDP and economic development level are on the impact of power supply reliability, namely requirement is reached for load density, area that returns of investment are good to allow in its reliability level, by one-level, to give top priority to what is the most important, promote returns of investment.

4th step, sets up power distribution network Investment Optimization Model, and using different for each department powered types load as optimized variable, maximum as optimization aim using whole district's returns of investment, investment budgey is as constraint.

Such as formula (8) ~ (9), calculate the power distribution network investment prioritization scheme after considering reliability and economy.

Optimization aim: $\mathrm{MAX}\left(\underset{i\&Element;G}{\mathrm{\&Sigma;}}{k}_i{L}_{\mathrm{pi}}\right)---\left(8\right)$

Constraint condition: $\begin{array}{c}0\&le;L_{\mathrm{pi}}\&le;L_{\mathrm{pi}\max }\\ C_r=\underset{i\&Element;G}{\mathrm{\&Sigma;}}\left(L_{\mathrm{ci}}{C}_{\mathrm{rui}}\right)\\ C_{\mathrm{pr}}=\underset{i\&Element;G}{\mathrm{\&Sigma;}}{L}_{\mathrm{pi}}{C}_{\mathrm{prui}}\\ C_l=\underset{i\&Element;G}{\mathrm{\&Sigma;}}{d}_i{L}_{\mathrm{ci}}{C}_{\mathrm{lui}}\\ C_{\mathrm{pl}}=\underset{\mathrm{iG}}{\mathrm{\&Sigma;}}{d}_i{L}_{\mathrm{pi}}(C_{\mathrm{plui}}-C_{\mathrm{lui}})\\ C_r+C_{\mathrm{pr}}+C_l+C_{\mathrm{pl}}\&le;Y\end{array}---\left(9\right)$

Wherein, G is power supply zone set; K is returns of investment evaluation index; L _pfor variable to be optimized, the subregion that expression present situation year returns of investment are good can promote the load of power supply reliability further; L _pmaxfor the upper load limit of power supply reliability subregion can be promoted; L _cfor present situation year load; C _rfor not considering load growth, only because of the cost needed for the power supply reliability lifting of target year, C _rufor the specific load cost under this condition needed for power supply reliability lifting; C _prfor reliability promotes subregion because of the extra cost needed for reliability lifting; C _prufor the specific load cost needed for power supply reliability lifting; C _lfor the cost needed for the load increase of present situation year; D is target year load growth rate; C _lufor increasing the cost needed for specific load under present situation year reliability level; C _plfor reliability promotes the cost needed for partition load increase, C _plufor increasing the cost needed for specific load under reliability lifting zoning objectives year reliability level; Y is investment budgey.

The invention has the beneficial effects as follows, the present invention coordinates mutually from public resource and user resources, three aspects such as growth requirement and the investment ability is coordinated mutually, rural area electric pressure coordinated development carry out investment and distribute rationally, solve distribution network planning Problems existing preferably.The present invention increases specific load cost under promoting cost and setting reliability level by data fitting determination specific load reliability; Then formed and loss of outage by the user of dissimilar subregion, determine the returns of investment of respective partition; Finally be target to the maximum with returns of investment, set up power distribution network investment model of optimizing allocation, achieve the optimum allocation of planning capital investment shares, improve the efficiency of the operation of capital.

The present invention is applicable to the investment planning of power distribution network.

Accompanying drawing explanation

Fig. 1 is the inventive method investment Optimization Steps process flow diagram;

Fig. 2 is unit load investment and power supply reliability curve map;

Fig. 3 is for increasing specific load investment and power supply reliability curve map;

Fig. 4 is returns of investment Process of Comprehensive Assessment figure.

Embodiment

The present embodiment is implemented under premised on technical solution of the present invention, gives detailed embodiment and concrete operating process.As shown in Figure 1, returns of investment Process of Comprehensive Assessment as shown in Figure 4 for the present embodiment investment Optimization Steps.

Example of the present invention is based on certain city year actual electric network structure, analysis ought regional economic structure's feature during the lunar New Year, and with reference to the subregion reliability objectives that distribution network planning Guidance Rule is recommended, to determine the relevant economic loss index that has a power failure, show that specific investment increases delivery, specific investment increases the weight supplying the indexs such as load, policy guidance, social loss of outage, the Investment Allocation after utilizing power distribution network optimization of investment model to calculate final optimization pass in conjunction with statistics again.Area power grid to be analyzed and economy data are in table 1 and table 2.

Table 1 certain utility grid object of planning year all kinds of service areas reliability objectives (%)

Powered types	A	B	C	D
					2015	99.983	99.954	99.897	99.828

Each powered types region, certain city of table 2 each industry unit quantity of electricity proportion

	Resident	Trade financing	Industry	Public utilities	Agricultural
						A	42％	35.4％	5％	17.6％	0％
B	31％	13.5％	48％	7％	0.5％
						C	42％	14％	36％	5％	3％
D	45％	2％	14％	2％	37％

The present embodiment is implemented by following steps.

The first step, through type simulates reliability and promotes cost of investment, increases specific load cost, considers the funtcional relationship between the cost of investment of load growth and electric network reliability and reliability, as Fig. 2 ~ Fig. 3.

$\begin{array}{c}{C}_{\mathrm{rui}}=80128.5583051816(r_{\mathrm{ei}}^3-r_{\mathrm{ci}}^3)-23984923.2822767(r_{\mathrm{ei}}^2-r_{\mathrm{ci}}^2)\\ +2393140077.40188(r_{\mathrm{ei}}-r_{\mathrm{ci}})-7959332250.063\end{array}$

$\begin{array}{c}{C}_{\mathrm{lui}}=6134.5991381183r_{\mathrm{ei}}^3-20107483.8569366r_{\mathrm{ei}}^2\\ +207464227.69024r_{\mathrm{ei}}-668061892949.9496\end{array}$

C _ri＝15100C _rui

C _li＝400C _lui

C＝∑ _i∈G(C _ri+C _li)

Second step, by operation of power networks data, counts all kinds of industry electrogenesis ratio, as shown in table 3.Formula proposed by the invention is utilized to calculate each powered types region loss of outage (comprehensive electrogenesis ratio), as shown in table 4.This example uses Delphi method to increase delivery to specific investment, and specific investment increases for Index Weights weights such as loads, and Delphi method uses the metrics evaluation suggestion of 8 separate sources, and result is as table 5.

The each type load electrogenesis ratio of table 3 (unit: unit/kWh)

	Resident	Trade financing	Industry	Public utilities	Agricultural
						Electrogenesis ratio	11.5	220	150	413	4.65

Table 4 each powered types region loss of outage (unit: unit/kWh)

	Resident	Trade financing	Industry	Public utilities	Agricultural	Add up to
							A	4.83	77.88	7.5	72.688	0	162.898
B	3.565	29.7	72	28.91	0.02325	134.1983
							C	4.83	30.8	54	20.65	0.1395	110.4195
D	5.175	4.4	21	8.26	1.7205	40.5555

The each index weights of table 5

4th step, according to the relation estimated between the investment total expenses C of gained and investment budgey Y, the rationality of target year power supply reliability setting can be determined, need the indices numerical value using first two steps gained in computation process, and obtain each power supply zone power distribution network returns of investment comprehensive evaluation result as table 6.

Table 6 somewhere present situation year each power supply zone power distribution network returns of investment comprehensive evaluation result

3rd step, sets up power distribution network Investment Optimization Model according to formula, calculates the power distribution network investment prioritization scheme after considering reliability and economy; Final Investment Allocation scheme is as table 7.

Table 7 somewhere each power supply zone Investment Allocation project period scheme (unit: hundred million yuan)

	R1	R2	R3	R4	R5	R6	R7	R8	R9	R10	R11	R12
													A	19.565	-	-	-	-	-	-	-	-	-	-	-
B	7.147	1.082	25.582	2.289	1.740	0.982	-	0.097	0.306	0.003	2.785	1.259
													C	5.954	8.333	5.443	9.408	0.729	1.358	1.532	0.790	5.509	3.910	1.203	2.262
D	1.397	1.990	5.400	5.317	0.749	0.969	0.964	2.019	1.756	0.362	0.589	1.221
													Add up to	34.062	11.405	36.425	17.014	3.218	3.309	2.496	2.906	7.571	4.275	4.577	4.742

。

Claims (5)

1. the distribution network planning coordinated mutually based on reliability and economy invests an optimization method, it is characterized in that, described method increases specific load cost under first promoting cost and setting reliability level by data fitting determination specific load reliability; Then formed and loss of outage by the user of dissimilar subregion, determine the returns of investment of respective partition; Finally be target to the maximum with returns of investment, set up power distribution network investment model of optimizing allocation, realize the optimum allocation of planning capital investment shares, improve the efficiency of the operation of capital;

Described method comprises the estimation of (1) investment cost; (2) estimation of investment efficiency; (3) target reasonable evaluation (4) sets up power distribution network Investment Optimization Model.

2. the distribution network planning coordinated mutually based on reliability and economy according to claim 1 invests optimization method, it is characterized in that, described investment cost estimation comprises reliability and promotes cost of investment estimation, increases specific load cost estimation, considers the estimation of the cost of investment of load growth and electric network reliability;

Described reliability promotes cost of investment estimation:

By many ground electrical network characteristic of sampling, get specific load investment and reliability index data relationship, polynomial fitting method can draw not to be considered in load variations situation, and promote the variation relation between cost of investment needed for power supply reliability and reliability index, its form is as follows:

$C_{\mathrm{rui}}=a(r_{\mathrm{ei}}^3-r_{\mathrm{ci}}^3)-b(r_{\mathrm{ei}}^2-r_{\mathrm{ci}}^2)-c(r_{\mathrm{ei}}^1-r_{\mathrm{ci}}^1)-d---\left(1\right)$

In formula: C _ruifor region i specific load reliability promotes cost; r _eiand r _cibe respectively region i target year and present situation year power supply reliability level.

Utilize formula (1), power supply area i reliability can be obtained and promote required cost, shown in (2):

C _ri＝L _ciC _rui(2)

In formula: C _rifor power supply area i reliability promotes required cost; L _cifor power supply area i present situation year load level;

The cost estimation of described increase specific load:

By many ground electrical network characteristic of sampling, get specific load investment and reliability index data relationship, polynomial fitting method can draw not to be considered in load variations situation, promote the variation relation between cost of investment needed for power supply reliability and reliability index, its form is such as formula (3):

$C_{\mathrm{lui}}=a^{\&prime;}{r}_{\mathrm{ei}}^3+b^{\&prime;}{r}_{\mathrm{ei}}^2+c^{\&prime;}{r}_{\mathrm{ei}}^1+d^{\&prime;}---\left(3\right)$

According to formula (3), cost C needed for power supply area i load growth can be obtained _li, shown in (4):

C _li＝(L _ei-L _ci)C _lui(4)

In formula: L _eifor region i target year load level;

The described cost of investment estimation considering load growth and electric network reliability:

Under the condition that known each power supply area reliability promotes cost and load growth cost, can estimate and invest total expenses with specification needed for whole power supply area, shown in (5);

C＝Σ _i∈G(C _ri+C _li) (5)

In formula: C is whole power supply area required investment total expenses; G is the set that power supply area subregion is formed.

3. the distribution network planning coordinated mutually based on reliability and economy according to claim 1 invests optimization method, it is characterized in that, described estimation of investment efficiency adopts comprehensive electrogenesis to carry out estimation loss of outage OC than method, and computing formula is such as formula (6):

OC＝AOC×L×K (6)

In formula: K is comprehensive electrogenesis ratio, AOC is power off time per family, and L is load level;

Comprehensive electrogenesis to be weighted by all types of user electrogenesis ratio than K and to form, and computing method are provided by formula (7):

K＝k _j×d _j+k _c1×d _c1+k _c2×d _c2+k _c3×d _c3+k _x×d _x(7)

Wherein: k _jfor electrogenesis ratio, the k of resident _c1for electrogenesis ratio, the k of trade financing _c2for electrogenesis ratio, the k of industry _c3for utility electrogenesis ratio, k _xfor the electrogenesis ratio of agricultural; d _jfor electricity consumption ratio, the d of resident _c1for electricity consumption ratio, the d of trade financing _c2for electricity consumption ratio, the d of industry _c3for utility electricity consumption ratio, d _xfor the electricity consumption ratio of agricultural.

4. the distribution network planning coordinated mutually based on reliability and economy according to claim 1 invests optimization method, it is characterized in that, described target reasonable evaluation, according to the relation between the investment total expenses C of estimation gained and investment budgey Y, can determine the rationality of target year power supply reliability setting:

1) work as Y=C, show that budget conforms to required investment cost, power supply area can reach the reliability objectives of setting, distributes the investment of each subregion by formula (5-5);

2) Y<C is worked as, show budgetary shortfall, target year reliability objectives need be reset, specifically increase the mode of step-length by setting between rci and rei, draw the relation curve between reliability and investment cost, choose a point nearest with budget as the reliability objectives under this budget condition;

3) Y>C is worked as, show that budget is comparatively sufficient, by optimization of investment allocative decision, under ensureing that each subregion reaches the prerequisite of setting reliability objectives, consider that load density, GDP and economic development level are on the impact of power supply reliability, namely requirement is reached for load density, area that returns of investment are good to allow in its reliability level, by one-level, to give top priority to what is the most important, promote returns of investment.

5. the distribution network planning coordinated mutually based on reliability and economy according to claim 1 invests optimization method, it is characterized in that, describedly sets up power distribution network Investment Optimization Model:

Optimization aim: $\mathrm{MAX}\left(\underset{i\&Element;G}{\mathrm{\&Sigma;}}{k}_i{L}_{\mathrm{pi}}\right)---\left(8\right)$

Constraint condition: $\begin{array}{c}0\&le;L_{\mathrm{pi}}\&le;L_{\mathrm{pi}\max }\\ C_r=\underset{i\&Element;G}{\mathrm{\&Sigma;}}\left(L_{\mathrm{ci}}{C}_{\mathrm{rui}}\right)\\ C_{\mathrm{pr}}=\underset{i\&Element;G}{\mathrm{\&Sigma;}}{L}_{\mathrm{pi}}{C}_{\mathrm{prui}}\\ C_l=\underset{i\&Element;G}{\mathrm{\&Sigma;}}{d}_i{L}_{\mathrm{ci}}{C}_{\mathrm{lui}}\\ C_{\mathrm{pl}}=\underset{\mathrm{iG}}{\mathrm{\&Sigma;}}{d}_i{L}_{\mathrm{pi}}(C_{\mathrm{plui}}-C_{\mathrm{lui}})\\ C_r+C_{\mathrm{pr}}+C_l+C_{\mathrm{pl}}\&le;Y\end{array}---\left(9\right)$

Wherein, G is power supply zone set; K is returns of investment evaluation index; L _pfor variable to be optimized, the subregion that expression present situation year returns of investment are good can promote the load of power supply reliability further; L _pmaxfor the upper load limit of power supply reliability subregion can be promoted; L _cfor present situation year load; C _rfor not considering load growth, only because of the cost needed for the power supply reliability lifting of target year, C _rufor the specific load cost under this condition needed for power supply reliability lifting; C _prfor reliability promotes subregion because of the extra cost needed for reliability lifting; C _prufor the specific load cost needed for power supply reliability lifting; C _lfor the cost needed for the load increase of present situation year; D is target year load growth rate; C _lufor increasing the cost needed for specific load under present situation year reliability level; C _plfor reliability promotes the cost needed for partition load increase, C _plufor increasing the cost needed for specific load under reliability lifting zoning objectives year reliability level; Y is investment budgey.