CN106960270A - A kind of distribution transformer benefit potential evaluation method for considering Demand Side Response - Google Patents

Abstract

The invention discloses a kind of distribution transformer benefit potential evaluation method for considering Demand Side Response, China's network load peak-valley difference is in constantly to widen trend in recent years, traditionally the distribution network planning mode of foundation causes distribution transformer benefit to reduce year by year, increases the cost of investment of power distribution network.With becoming better and approaching perfection day by day for DSM, load peak is reduced using demand response means, so that reducing cost has become possibility.On the basis of the spike behavior of analysis distribution transformer, set up distribution transformer overall life cycle cost model, the relation of the transfer of distribution transformer peakload and infusion of financial resources under Demand Side Response is analyzed, the distribution transformer benefit Potential Evaluation model for considering Demand Side Response is further set up.Simulation analysis are carried out using the Distribution Network Load Data historical data of city of Jiangsu province section, are as a result shown, under Demand Side Response, there are distribution transformer benefit larger potentiality can excavate, scientific basis is provided for electric company's innovation investment tactics.

Description

A kind of distribution transformer benefit potential evaluation method for considering Demand Side Response

Technical field

Invention is related to a kind of distribution transformer benefit potential evaluation method for considering Demand Side Response, belongs to power system prison Survey, analyze and control technology field.

Background technology

Electric power enterprise is increasingly dependent on the economic benefit of production transmission equipment, to coordinate the practical of State Grid's system reform Demand, economic benefit basic theory is provided for the construction of active distribution network, and Critical Peak Pricing policy is put into effect in Jiangsu Power Company While, influence of the research Critical Peak Pricing to benefit, so as to be that Utilities Electric Co.'s dsm and power distribution network investment provide reference.

Study less in terms of the relation of power distribution network benefit and Demand Side Response both at home and abroad, mainly have using data envelopment Mode is estimated to power distribution network benefit, power distribution network benefit is estimated using optimized algorithm, power distribution network operational efficiency is considered And the method such as optimizing to its benefit, these researchs are not enough to the consideration in terms of Demand Side Response, it is difficult to adapt to modern electric Policy and technology.

Choose the switching data progress analysis of more than 9000, certain region and find that distribution transformer load data are rendered obvious by rush hour Less, the characteristics of low ebb time is more, because the characteristics of newly-built community is more, cell occupancy rate is low, distribution transforming yearly load factor is less than mostly 7%, operational efficiency is low.A typical distribution transforming is chosen, using year load maximum as standard, yearly load curve is normalized Processing, obtains the yearly load curve of typical distribution transforming.

As depicted in figs. 1 and 2, load value for peak load 10% to 40% between account for the 75.28% of integral load value； Load value for peak load 80% to 100% between account for the 2% of integral load value.Therefore deduce that, distribution transformer is born Significantly, operational efficiency is low, and peakload value accounting is less, with by cutting down what peakload was increased the benefit for lotus spike behavior Potentiality.

The content of the invention：

The technical problems to be solved by the invention are in view of the shortcomings of the prior art and provide a kind of consideration Demand-side The distribution transformer benefit potential evaluation method of response.

The present invention to achieve the above object, is adopted the following technical scheme that：

A kind of distribution transformer benefit potential evaluation method for considering Demand Side Response, comprises the following steps：

1) distribution transformer overall life cycle cost model is set up；

2) distribution transformer overall life cycle cost and load peak characteristic relation model are set up；

3) distribution transformer spike under demand response is set up using consumer psychology model to cut down with the pass injected capital into It is model, and makes assessment.

As optimization, the step 1) in can be expressed as distribution transformer, overall life cycle cost：

LCC=IC+OC+DC (1)

Wherein, LCC represents the overall life cycle cost of distribution transforming, and IC is expressed as initial outlay cost, and OC represents operating cost； FC represents failure cost, and DC represents scrap cost；

Capacity and cost of investment relation are as follows：

IC=C_tA+C_oS_N (2)

Wherein IC is a total cost of investment of transformer, C_tUsed for unit sapce charge, A is floor space；C_oBecome for distribution Depressor unit acquisition cost；S_NFor single transformer rated capacity.

It can show that distribution transformer year operation electric energy loss expression formula is：

ΔW_i=(P₀+K_qQ₀)T_a+β_i ²(P_k+K_qQ_k)τ (3)

Wherein, P₀Represent iron loss, P_kRepresent copper loss, Q_kRepresent short-circuit reactive loss, Q₀Unloaded reactive loss is represented, β is represented Transformer maximum load rate, K_qRepresent non-work economic equivalent, T_aThe annual hours of operation of distribution transformer is represented, τ represents distribution change Hourage is lost in depressor peak load；

Distribution transformer operating cost is expressed as：

OC=Δs WC_g+MC (4)

Wherein, to calculate, C_gRepresent unit of electrical energy loss electricity price, MC indication transformer Maintenance and Repair costs, only with Transformer number of units is relevant；

Transformer scrap cost is expressed as：

DC=- η C₀S_N (5)

Wherein, η represents rate of discount, therefore distribution transformer overall life cycle cost can be expressed as：

Analyzed as optimization, in the step 2 under the premise of distribution transforming characteristic, do not consider idle in computed losses, and will be with The incoherent factor of capacity is equivalent into a constant, and formula (8) can be reduced to:

Wherein：

The rule of distribution transformer is chosen according to electric company, distribution transformer maximum load is multiplied by coefficient matches somebody with somebody as selection Piezoelectric transformer capacity foundation, it is assumed that year load growth rate in somewhere is γ, then the distribution transforming is because of the capacity of selection：

S_N=α (1+r)ⁿP_max (9)

Cost needed for the distribution transformer and the relation of load peak can draw by formula (9) and formula (11), if Peakload is from P_maxIt is cut to P '_max, then from the point of view of overall life cycle cost, the distribution transformer saves overall life cycle cost For：

Formula (9) and (10) elaborate the incidence relation of overall life cycle cost and load peak value, can be with using the formula Obtain saving the cost fund of transformer after peakload declines.

As optimization, in the step 3, when the electricity price after raising does not have much differences with former electricity price, resident does not change The change of the electricity charge before and after implementation electrovalence policy can also be born by becoming power mode, and now resident often schemes convenient or comfortable without changing Become power mode；When Resident Electricity Price bring up to resident it is unaffordable when, resident can have to some household electrical appliance Keep away peak operation or directly use energy-saving electric appliance instead to reduce power consumption.And some electricity consumptions are necessary, change electricity price anyway, use Family is also impossible to change the power consumption of this part；Stimulation of the sales rate of electricity to resident equally has a just noticeable difference, when When sales rate of electricity is less than the just noticeable difference, resident is substantially reactionless；And when sales rate of electricity is more than a higher limit, Resident will approach to saturation there is no more transferable loads, responding ability；Reaction of the resident to electricity price can be used Cool load translating ratio is described, and is described using following formula：

G, d are respectively high electricity price and low electricity price, Δ gd=g-d；a_gd、b_gdRespectively user is poor to electricity price in dead band and line The higher limit in property area；K_gdFor linear zone slope；

Assuming that pure subsidy policy is taken user, the peakload that user itself cuts down is subsidized using fund, then user rings Peak load should meet relational expression with peak load before user response after answering：

P′_max=(1- λ_gd)P_max (14)

Wherein P '_maxRepresent peak load, P after user response_maxPeak load before user response is represented, with reference to formula (11) It can obtain：

Input cut down peak totle drilling cost be：

Wherein P₁(t) user response preload curve, P are represented₂(t) load curve after user response is represented, t0 represents to need Response is asked to perform start time, t1, which represents that demand response is performed, to be terminated, and Δ gd represents to adjust the cost needed for specific load.

With reference to formula (10) (13) (14), make power distribution network benefit maximum, then：

Beneficial effect：The present invention is compared with prior art：It is overall that the present invention obtains electricity using the smooth density estimation of core Density curve, analyzes the spike behavior of distribution transformer, and further sets up distribution transformer overall life cycle cost model, The relation of the transfer of distribution transformer peakload and infusion of financial resources under Demand Side Response is analyzed, is rung so as to set up consideration Demand-side The distribution transformer benefit Potential Evaluation model answered, and Simulation Example has been carried out, it can be seen that depositing for load peak by calculating The cost of investment of grid equipment is being increased, for distribution transforming, distribution transforming investment is directly related with capacity, and capacity of distribution transform is then It is that, by load peak is determined, reduction plans spike will significantly cut down distribution transforming investment, so as to cut down spike Load provides necessity and exploitativeness.

Brief description of the drawings：

Fig. 1 is the yearly load curve schematic diagram of typical distribution transforming in background of invention；

Fig. 2 is the yearly load curve analysis schematic diagram of typical distribution transforming in background of invention；

Fig. 3 is cool load translating ratio schematic diagram of the present invention；

Fig. 4 is the relation schematic diagram of distribution transforming infusion of financial resources of the present invention and benefit.

Embodiment：

The techniqueflow of invention is described in detail below in conjunction with the accompanying drawings：

A kind of distribution transformer benefit potential evaluation method for considering Demand Side Response, comprises the following steps：

1) distribution transformer overall life cycle cost model is set up；

2) distribution transformer overall life cycle cost and load peak characteristic relation model are set up；

3) distribution transformer spike under demand response is set up using consumer psychology model to cut down with the pass injected capital into It is model, and makes assessment.

As optimization, the step 1) in can be expressed as distribution transformer, overall life cycle cost：

LCC=IC+OC+DC (1)

Wherein, LCC represents the overall life cycle cost of distribution transforming, and IC is expressed as initial outlay cost, and OC represents operating cost； DC represents scrap cost；

Capacity and cost of investment relation are as follows：

IC=C_tA+C_oS_N (2)

Wherein IC is a total cost of investment of transformer, C_tUsed for unit sapce charge, A is floor space；C_oBecome for distribution Depressor unit acquisition cost；S_NFor single transformer rated capacity.

It can show that distribution transformer year operation electric energy loss expression formula is：

ΔW_i=(P₀+K_qQ₀)T_a+β_i ²(P_k+K_qQ_k)τ (3)

Wherein, P₀Represent iron loss, P_kRepresent copper loss, Q_kRepresent short-circuit reactive loss, Q₀Unloaded reactive loss is represented, β is represented Transformer maximum load rate, K_qRepresent non-work economic equivalent, T_aThe annual hours of operation of distribution transformer is represented, τ represents distribution change Hourage is lost in depressor peak load；

Distribution transformer operating cost is expressed as：

OC=Δs WC_g+MC (4)

Wherein, to calculate, C_gRepresent unit of electrical energy loss electricity price, MC indication transformer Maintenance and Repair costs, only with Transformer number of units is relevant；

Transformer scrap cost is expressed as：

DC=- η C₀S_N (5)

Wherein, η represents rate of discount, therefore distribution transformer overall life cycle cost can be expressed as：

Analyzed as optimization, in the step 2 under the premise of distribution transforming characteristic, do not consider idle in computed losses, and will be with The incoherent factor of capacity is equivalent into a constant, and formula (8) can be reduced to:

Wherein：

The rule of distribution transformer is chosen according to electric company, distribution transformer maximum load is multiplied by coefficient matches somebody with somebody as selection Piezoelectric transformer capacity foundation, it is assumed that year load growth rate in somewhere is γ, then the distribution transforming is because of the capacity of selection：

S_N=α (1+r)ⁿP_max (9)

Cost needed for the distribution transformer and the relation of load peak can draw by formula (7) and formula (9), such as fruit point Peak load is from P_maxIt is cut to P '_max, then from the point of view of overall life cycle cost, the distribution transformer saves overall life cycle cost For：

Formula (11) and (12) elaborate the incidence relation of overall life cycle cost and load peak value, can be with using the formula Obtain saving the cost fund of transformer after peakload declines.

As optimization, in the step 3, when the electricity price after raising and little former electricity price difference, resident does not change use It electrically can also bear to implement the change of the electricity charge before and after electrovalence policy, now resident is often because convenient or comfort is without changing Power mode.When Resident Electricity Price brings up to the unaffordable scope of resident, resident can keep away some household electrical appliance peak operation Or directly use energy-saving electric appliance instead to reduce power consumption.And for some necessary electricity consumptions, no matter how electricity price changes, this part of user Power consumption it is constant.Stimulation of the sales rate of electricity to resident equally has a just noticeable difference, when sales rate of electricity is less than this most When I feels difference, resident is substantially reactionless；And when sales rate of electricity is more than a higher limit, resident will be there is no More transferable loads, responding ability approaches to saturation.Reaction of the resident to electricity price can be described with cool load translating ratio, Described using following formula：

G, d are respectively high electricity price and low electricity price, Δ gd=g-d；a_gd、b_gdRespectively user is poor to electricity price in dead band and line The higher limit in property area；K_gdFor linear zone slope；

Assuming that pure subsidy policy is taken user, the peakload that user itself cuts down is subsidized using fund, then user rings Peak load should meet relational expression with peak load before user response after answering：

P′_max=(1- λ_gd)P_max (12)

Wherein P '_maxRepresent peak load, P after user response_maxPeak load before user response is represented, with reference to formula (11) It can obtain：

Input cut down peak totle drilling cost be：

Wherein P₁(t) user response preload curve, P are represented₂(t) load curve after user response is represented, t0 represents to need Response is asked to perform start time, t1, which represents that demand response is performed, to be terminated, and Δ gd represents to adjust the cost needed for specific load；

With reference to formula (10) (13) (14), make power distribution network benefit maximum, then：

Embodiment

According to Soviet Union's valency [2007] No. 208 files of work, provide that the electricity price of big industrial user is as follows：

The big industrial user's electricity rate table in the Jiangsu Province of table 2

The present invention sets a in parameter r=0.04 in formula (11), formula (15)_gd=0.05, b_gd=3, K_gd=10, formula (12) distribution network electric energy loss calculation of the parameter reference paper based on tree network trend.

Monomer distribution transforming benefit Potential Evaluation

According to the Response System of Critical Peak Pricing in document, peak load curtailment of subsidy is carried out through assuming certain area to user, Cool load translating ratio meets consumer psychology principle, if most 30% load participates in response, can set up input-peak clipping response and close System.

When peak clipping amplitude reaches 13.8%, electric company's Income Maximum reaches 1861 yuan, now transformer station high-voltage side bus Efficiency brings up to 0.4182 from original 0.3700, and the subsidy now given is 2.22 yuan/kilowatt hour.With reference to U.S.'s subsidized price Mechanism, the price of peak period can be 4-6 times of usually price, and this subsidized price is 4.12 times of usually price, therefore the benefit It is attached in rational interval range.Result of calculation shows that 539 yuan of this total input cost obtains 854 yuan of benefit fund.

10kV feeder line benefit Potential Evaluations

The nine station power distribution transformers chosen on 1 feeder line of Jiangsu city section are analyzed, and result of calculation shows, its In 7 participate in demand responses can produce response benefit, to distribution transforming carry out analysis weighting, it is as shown in the table：

The feeder line distribution transforming benefit ratio of table 3

Table 3 Feeder benefit ratio

As can be seen from the above table, the average peak clipping 2.67% of distribution transforming, injects capital into 3424 yuan, obtains benefit fund totally 2960 Member.

110kV main transformers and section benefit Potential Evaluation

The main transformer for choosing Jiangsu city section is analyzed, by calculating, and cost-effective 5.21 ten thousand yuan altogether, puts into peak clipping 0.79 ten thousand yuan of fund, distribution transforming efficiency value is lifted to 0.5696 from 0.5413.Cut down peak 6.5%.

On the basis of main transformer is assessed, whole district's performance evaluation is carried out to the section, the section is matched somebody with somebody with 7 feeder lines, 210 Become, 3385482 data to its annual typical day are analyzed, and by the way of parallel computation, are evaluated changing region：

The section feeder line benefit ratio of table 4

Table 5 Area Feeder benefit ratio

Example shows that the section has 180 distribution transformings to participate in peak clipping, injects capital into 13.92 ten thousand yuan, obtains benefit fund Totally 14.06 ten thousand yuan.In summary, while considering the influence of main transformer and distribution transforming, the section, which has altogether, can obtain benefit 19.13 ten thousand Member.

Claims (4)

1. a kind of distribution transformer benefit potential evaluation method for considering Demand Side Response, it is characterised in that：Comprise the following steps：

1) distribution transformer overall life cycle cost model is set up；

2) distribution transformer overall life cycle cost and load peak characteristic relation model are set up；

3) distribution transformer spike under demand response is set up using consumer psychology model to cut down with the relation mould injected capital into Type, and make assessment.

2. the distribution transformer benefit potential evaluation method according to claim 1 for considering Demand Side Response, its feature exists In：The step 1) in be expressed as distribution transformer, overall life cycle cost：

LCC=IC+OC+DC (1)

Wherein, LCC represents the overall life cycle cost of distribution transforming, and IC represents initial outlay cost, and OC represents operating cost, and DC is represented Scrap cost；

Capacity and cost of investment relation are as follows：

IC=C_tA+C_oS_N (2)

Wherein IC is a total cost of investment of transformer, C_tUsed for unit sapce charge, A is floor space；C_oFor distribution transformer Unit acquisition cost；S_NFor single transformer rated capacity；

It can show that distribution transformer year operation electric energy loss expression formula is：

ΔW_i=(P₀+K_qQ₀)T_a+β_i ²(P_k+K_qQ_k)τ (3)

Wherein, P₀Represent iron loss, P_kRepresent copper loss, Q_kRepresent short-circuit reactive loss, Q₀Unloaded reactive loss is represented, β represents transformation Device maximum load rate, K_qRepresent non-work economic equivalent, T_aThe annual hours of operation of distribution transformer is represented, τ represents distribution transformer Hourage is lost in peak load；

Distribution transformer operating cost is expressed as：

OC=Δs WC_g+MC (4)

Wherein, C_gUnit of electrical energy loss electricity price is represented, MC indication transformer Maintenance and Repair costs are only relevant with transformer number of units；

Transformer scrap cost is expressed as：

DC=- η C₀S_N (5)

Wherein, η represents rate of discount, therefore distribution transformer overall life cycle cost is expressed as：

$\begin{array}{c}LCC=C_{t}A+\left(1-\mathrm{\η}\right)C_o{S}_N+\\ \underset{i=1}{\overset{n}{\mathrm{\Σ}}}{\mathrm{\λ}}_i\left\{C_g\[\left(P_0+K_q{Q}_0\right)T_a+{{\mathrm{\β}}_i}^2\left(P_k+K_q{Q}_k\right)\mathrm{\τ}\]+{\mathrm{MC}}_i\right\}\end{array}---\left(6\right)$

3. the distribution transformer benefit potential evaluation method according to claim 1 for considering Demand Side Response, its feature exists In：In the step 2 analyze distribution transforming characteristic under the premise of, do not consider idle in computed losses, and will with capacity it is incoherent because Element is equivalent into a constant, and formula (6) is reduced to:

$LCC=B+(1-\mathrm{\η})C_o{S}_N+\underset{i=1}{\overset{n}{\Σ}}{\mathrm{\λ}}_i{C}_g(a_1{S}_N^{b1}+{\mathrm{\β}}_i^2{a}_2{S}_N^{b2})---\left(7\right)$

Wherein：

$B=C_{t}A+\underset{i=1}{\overset{n}{\Σ}}{\mathrm{\λ}}_i{\mathrm{MC}}_i---\left(8\right)$

The rule of distribution transformer is chosen according to electric company, distribution transformer maximum load is multiplied by coefficient and become as distribution is chosen Depressor capacity foundation, it is assumed that load growth rate in somewhere year is γ, then the capacity that should be chosen with allergic effect is：

S_N=α (1+r)ⁿP_max (9)

Cost needed for the distribution transformer and the relation of load peak can be drawn by formula (8) and formula (9), if spike is negative Lotus is from P_maxIt is cut to P '_max, then from the point of view of overall life cycle cost, the distribution transformer saves overall life cycle cost and is：

$\begin{array}{c}\mathrm{\Δ}LCC=LCC-{\mathrm{LCC}}^{\′}\\ =\left(1-\mathrm{\η}\right)\left(S_N-S_N^{\′}\right)C_o+\underset{i=1}{\overset{n}{\mathrm{\Σ}}}{\mathrm{\λ}}_i{C}_g\left(a_1{S}_N^{b1}+{\mathrm{\β}}_i^2{a}_2{S}_N^{b2}\right)\\ -\underset{i=1}{\overset{n}{\mathrm{\Σ}}}{\mathrm{\λ}}_i{C}_g\left(a_1{S}_N^{\′b1}+{\mathrm{\β}}_i^2{a}_2{S}_N^{\′b2}\right)\end{array}---\left(10\right)$

Formula (9) and (10) elaborate the incidence relation of overall life cycle cost and load peak value, can be obtained using the formula Peakload saves the cost fund of transformer after declining.

4. the distribution transformer benefit potential evaluation method according to claim 1 for considering Demand Side Response, its feature exists In：In the step 3, when the electricity price after raising and little former electricity price difference, resident, which does not change power mode, can also bear The change of the electricity charge before and after implementation electrovalence policy, now resident is often because convenient or comfort is without changing power mode.Work as residence People's electricity price brings up to the unaffordable scope of resident, and some household electrical appliance can be kept away peak operation or directly use energy-conservation instead by resident Electrical equipment reduces power consumption.But for some necessary electricity consumptions, no matter how electricity price changes, the electricity consumption of this part of user Amount is constant.Stimulation of the sales rate of electricity to resident equally has a just noticeable difference, when sales rate of electricity is felt less than the most I When poor, resident is substantially reactionless；And when sales rate of electricity is more than a higher limit, resident will there is no more Transferable load, responding ability approaches to saturation.Reaction of the resident to electricity price can be described with cool load translating ratio, under Formula is described：

${\mathrm{\λ}}_{gd}=\left\{\begin{array}{c}0,(0\≤\mathrm{\Δ}gd\≤a_{gd})\\ K_{gd}(\mathrm{\Δ}gd-a_{gd}),(a_{gd}\≤\mathrm{\Δ}gd\≤b_{gd})\\ {\mathrm{\λ}}_{gd}^{\max },(\mathrm{\Δ}gd\≥b_{gd})\end{array}\right.---\left(11\right)$

G, d are respectively high electricity price and low electricity price, Δ gd=g-d；a_gd、b_gdRespectively user to electricity price difference in dead band and linear zone Higher limit；K_gdFor linear zone slope；

Assuming that pure subsidy policy is taken user, subsidize the peakload that user itself cuts down, then after user response using fund Peak load should meet relational expression with peak load before user response：

P′_max=(1- λ_gd)P_max (12)

Wherein P '_maxRepresent peak load, P after user response_maxPeak load before user response is represented, can be with reference to formula (11) Obtain：

$P_{\max }^{\′}=\left\{\begin{array}{c}{P}_{max},(0\≤\mathrm{\Δ}gd\≤a_{gd})\\ \[1-K_{gd}(\mathrm{\Δ}gd-a_{gd})\]P_{max},(a_{gd}\≤\mathrm{\Δ}gd\≤b_{gd})\\ \[1-K_{gd}(b_{gd}-a_{gd})\]P_{max},(\mathrm{\Δ}gd\≥b_{gd})\end{array}\right.---\left(13\right)$

Input cut down peak totle drilling cost be：

$COST=\mathrm{\Δ}gd{\∫}_{t0}^{t1}\[P_1\left(t\right)-P_2\left(t\right)\]dt---\left(14\right)$

Wherein P₁(t) user response preload curve, P are represented₂(t) load curve after user response is represented, t0 represents that demand is rung Start time should be performed, t1, which represents that demand response is performed, to be terminated, and Δ gd represents to adjust the cost needed for specific load.

With reference to formula (10) (13) (14), make power distribution network benefit maximum, then：

$\begin{array}{cc}\max & \mathrm{\Δ}LCC-COST\\ s.t.& 0\≤\mathrm{\Δ}gd\≤{\mathrm{\Δgd}}_{\max }\\ & P_{\max }^{\′}=\left(1-{\mathrm{\λ}}_{gd}\right)P_{\max }\\ & S_N=\mathrm{\α}{\left(1+r\right)}^n{P}_{\max }\end{array}.---\left(15\right)$