CN104578183A - Tie-line power transmission plan optimization method for improving low-carbon level of electric system - Google Patents

Abstract

The invention discloses a tie-line power transmission plane optimization method for improving the low-carbon level of an electric system. According to the method, an optimization analysis model is established, related data of the system, the load curve and the wind power output prediction curve of the system and tie-line power transmission plans to be selected are collected, the related data are substituted into the optimization analysis model and solved through optimization software, and through comparing and analyzing the multiple alternative power transmission plans, the power transmission plan lowest in operation cost is selected. According to wind power output, load prediction and other information a few days ago, through adopting the tie-line power transmission plan arranged in an optimization mode, wind power absorption space of a receiving end system can be sufficiently utilized for assisting a transmitting end system in absorbing wind power, and global system operation is optimized. System wind power absorption can be promoted, and practice guides are provided for optimization operation of a power grid.

Description

Improve the interconnection power transmission plan optimization method of the low carbonization level of electric power system

Technical field

The present invention relates to the optimization method of interconnection power transmission plan, specifically a kind of interconnection power transmission plan optimization method improving the low carbonization level of electric power system.

Background technology

The appearance of a series of crisis such as Global climate change, lack of energy makes the mankind have to again think deeply the development pattern of self.Adhere to energy-saving and emission-reduction, development low-carbon economy is the important channel that various countries realize sustainable development.The Chinese government makes to the world reducing discharging and promises to undertake, compares decline 40% ~ 45% in 2005 to the year two thousand twenty by realizing per GDP carbon emission amount.For reaching emission reduction targets, realize the sustainable development of energy supply, the exploitation of regenerative resource become the focus of attention of people.

China's energy resources and load center are the overall situation of contrary distribution, and trans-regional extensive long distance power transmission becomes abundant developing western region resource, ensures the important way of load center energy demand.Have larger fluctuation and uncertainty owing to exerting oneself, when only wind-powered electricity generation is sent at a distance, the utilance of Transmission Corridor is lower, and power transmission power controllability and economy are all poor.China " three Norths " regional wind-powered electricity generation and coal resources comparatively horn of plenty, for this reason, in conjunction with the endowment of resources in sending end area, " wind fire Ji mutually " becomes the universal way of the large-scale Energy Base of China " three Norths " regional development gradually.On the basis of rational proportion, " wind fire Ji mutually " can compensate the fluctuation of wind power output by the regulating power of thermoelectricity, ensure the power demand of Transmission Corridor.

Limit by the energy resource structure based on coal, the carbon emission that China's power industry produces accounts for China every year because combustion of fossil fuel causes the half of carbon emission total amount, has the advantages that discharge capacity is large, discharge intensity is high.Promise to undertake for reaching the reduction of discharging that China makes, it has been very urgent that power industry cuts down carbon emission, and wherein the non-fossil energies such as wind-powered electricity generation are greatly developed in an important choice of technology, improve wind-powered electricity generation ratio of dissolving in systems in which.In addition, in the low-carbon economy epoch, carbon emission is endowed certain Financial cost by the form such as carbon tax and carbon transaction, has raised the cost of electricity-generating of traditional thermal power generating technology.Power supply architecture based on thermal power generation makes the power industry in Some Domestic region face huge carbon emission reduction pressure, while the local non-fossil sources such as wind-powered electricity generation, photovoltaic of active development, outside district, the low carbonization development of feeding to Shandong Electric Power Group system of wind-powered electricity generation has important facilitation.The development scheme of " wind fire Ji mutually " ensure that power controllability and the transmission of electricity economy of power transmission passage, but due to sending end thermoelectricity regulating power deficiency, may cause abandoning wind under traditional dominant eigenvalues control model.

Due to the overall situation of China's Energy Load contrary distribution, building the mutual support of electric energy between transregional interconnection, feasible region becomes the inevitable choice meeting load center need for electricity, alleviate communications and transportation resource anxiety.The power control mode of existing interval interconnection is generally determines frequency, surely exchange power and tie-line bias control pattern.For the interconnection between large-scale power grid, traditional mode is convenient to the decentralized control of each regional power grid, is conducive to the safe and stable operation of maintenance system.But under low-carbon development model, during the problem of dissolving difficult in large-scale generation of electricity by new energy bases such as facing wind-powered electricity generation, for trans-regional interconnection, especially containing the transregional electric energy direct sending passage of non-fossil energy base direct sending load center, traditional dominant eigenvalues control model no longer meets the demand promoting new forms of energy power consumption, promote system low carbon development, exists and further optimizes room for promotion.

China's inland most area is by solar radiation on daytime, and liftoff more than 30 meters upper-level winds resources present the feature of large, the school closure on daytime of wind at night more, make wind power output have anti-peak-shaving capability more.In wind fire mutually Ji transmitting system, conventional power control model fully can not adapt to the fluctuation of wind power output and anti-peak-shaving capability, may occur abandoning wind, cause the low-carbon (LC) wasting of resources.In this context, if optimize the interconnection power transmission plan to load center power transmission, as adopted the power transmission plan with anti-peak-shaving capability, namely larger power is sent at night, although the peak regulation pressure of receiving end electrical network may be aggravated, but the anti-peak-shaving capability of wind-powered electricity generation can be adapted to preferably, thus wind is abandoned in minimizing.Under the cooperation of receiving-end system peak regulation resource, the optimization by power transmission plan promotes dissolving of sending end wind-powered electricity generation, thus obtains remarkable low-carbon (LC) benefit.For this reason, be necessary on the basis of given wind power output prediction curve, in conjunction with the system performance sending receiving end, analysis be optimized to the power transmission plan of passway for transmitting electricity.

Therefore, passage is sent at a distance for this type of large-scale Energy Base, on the basis that can predict the outcome in wind power output, the power transmission plan of Optimum passage, make full use of the wind electricity digestion space that receiving-end system has more than needed and promote dissolving of sending end area wind-powered electricity generation, wind is abandoned in effective minimizing, reduces the operating cost of system while promoting the low carbonization development of load center.

Summary of the invention

For solving the problem, the object of the present invention is to provide a kind of interconnection power transmission plan optimization method improving the low carbonization level of electric power system, the method is according to the information such as wind power output, load prediction a few days ago, by adopting the interconnection power transmission plan of Optimum, the wind electricity digestion space of receiving-end system can be made full use of, assist sending to dissolve wind-powered electricity generation, optimize global system and run.

For solving the problem, a kind of interconnection power transmission plan optimization method improving the low carbonization level of electric power system provided by the invention, comprises the following steps:

The first step, set up optimizing and analyzing model:

The total operating cost of system is min C _gen+ C _carbon

Wherein:

$C_{\mathrm{Gen}}=\underset{t\∈{\mathrm{\Ω}}_T}{\mathrm{\Σ}}\underset{k\∈{\mathrm{\Ω}}_K}{\mathrm{\Σ}}{c}_k^G\·(P_{t,k}^E+P_{t,k}^I)\·\mathrm{\Δt}$

$C_{\mathrm{Carbon}}=\underset{t\∈{\mathrm{\Ω}}_T}{\mathrm{\Σ}}\underset{k\∈{\mathrm{\Ω}}_K}{\mathrm{\Σ}}{c}^C\·e_k\·(P_{t,k}^E+P_{t,k}^I)\·\mathrm{\Δt}$

In formula, C _genfor the cost of electricity-generating of system; C _carbonfor the carbon emission cost of system; Ω _tfor optimizing period set; Ω _kfor the set of machine set type; c ^g _krepresent the unit cost of electricity-generating of kth class unit; c ^cthe Financial cost of representation unit carbon emission; e _krepresent the carbon emission that the generating of kLei unit unit produces; P ^e _t,kand P ⁱ _t,krepresent that interconnection sending end and receiving end kth class unit are exerted oneself at the meritorious of t respectively, subscript E and I represents sending end and receiving-end system respectively; The time span that Δ t problem of representation is analyzed;

Constraints comprises:

A, generation load Constraints of Equilibrium

$\underset{k\∈{\mathrm{\Ω}}_K}{\mathrm{\Σ}}{P}_{t,k}^E(1-{\mathrm{\σ}}_L)+\underset{k\∈{\mathrm{\Ω}}_K}{\mathrm{\Σ}}{P}_{t,k}^I=D_{\text{t}}$

In formula, σ _lfor the line loss rate of passway for transmitting electricity, D _tfor receiving-end system is at the load of t;

B, Climing constant

$-{\mathrm{\δ}}_k^D{P}_k^{\max }\≤P_{t,k}-P_{t-1,k}\≤{\mathrm{\δ}}_k^U{P}_k^{\max }$

In formula, δ ^d _k, δ ^u _kbe respectively the climbing rate representing kth class unit ascending, descending capacity, subscript max represents the installed capacity of all types of unit;

C, all kinds of unit output bound retrain

C1, for conventional power generation usage technology such as thermoelectricity, nuclear power and the reservoir type power plants with certain regulating power, to be constrained to:

$P_k^{\min }\≤P_{t,k}\≤P_k^{\text{max}}$

In formula, P ^min _krepresent the minimum load of all types of unit, P ^max _krepresent maximum installed capacity,

C2, for generation technologies such as wind-powered electricity generation, photovoltaic and plants without storage, to be constrained to:

$0{\≤P}_{t,k}\≤P_{t,k}^{\mathrm{FOR}}$

In formula, P ^fOR _t,kfor the predicted value of exerting oneself in t schedulable to kth class unit,

D, interconnection power transmission plan constraint

$f_{L,t}^{\min }\≤f_{L,t}\≤f_{L,t}^{\text{max}}$

In formula, f ^max _l,t, f ^min _l,tbe respectively the minimum and maximum performance number that t interconnection allows conveying, f _l,tfor passage is at the power transmission power of t,

Second step, collects the related data in the first step, and system loading curve and wind power output prediction curve, and designs interconnection power transmission to be selected plan;

3rd step, by the related data of collecting in second step, and system loading curve, wind power output prediction curve and interconnection power transmission plan to be selected substitute in the optimizing and analyzing model of the first step, and adopt Optimization Software to solve;

4th step, by the comparative analysis to many alternative power transmission plans, selects the power transmission plan that operating cost is minimum.

Further, when setting up optimizing and analyzing model, respectively modeling is carried out to all kinds of unit, to send, receiving-end system will all be considered as individual node, all kinds of unit all equivalence is single unit, equivalent unit capacity is the capacity sum of such each single unit, on system total load carries out that integration is connected on etc. value node.

Further, in described 3rd step, obtain the comparison diagram of the actual power curve of sending end wind-powered electricity generation and the statistical form of system operation cost, carbon emission amount and wind electricity digestion situation under different power transmission plan.

Preferably, the described Optimization Software adopted in the 3rd step is Cplex software.

Beneficial effect of the present invention is: it is with the problem that the is arranged to core of interconnection power transmission plan, optimizes the dissolving of sending wind-powered electricity generation, improves the low carbonization level of electric power system, and considers the extra operating cost that carbon emission brings to system; The analysis theory of application carbon emission flow, gives full play to load center and assists to dissolve the enthusiasm of wind-powered electricity generation; Adopt the power supply architecture modeling method based on machine set type, respectively analysis is optimized to multiple feasible power transmission plan, selected the power transmission plan of benefit the best by Comparative result.

The method, according to the information such as wind power output, load prediction a few days ago, by adopting the interconnection power transmission plan of Optimum, can make full use of the wind electricity digestion space of receiving-end system, assists sending to dissolve wind-powered electricity generation, optimizes global system and run.It can promote system wind electricity digestion, for the optimizing operation of electrical network provides practical advice.

Accompanying drawing explanation

Fig. 1 is flow chart of the present invention;

Fig. 2 is the typical day load curve figure at B regional load center;

Fig. 3 is the prediction curve figure that a few days ago exerts oneself of sending end A ground and receiving end B ground wind-powered electricity generation;

Fig. 4 is the comparison diagram of the actual power curve of sending end wind-powered electricity generation under different power transmission plan.

Embodiment

Below in conjunction with accompanying drawing and case data, provide detailed description of the present invention and application displaying.

Fig. 1 is the flow chart of the interconnection power transmission plan optimization method of the low carbonization level of this raising electric power system, and the first step first sets up optimizing and analyzing model.In the analysis of interconnection output power, need not pay close attention to the situation of exerting oneself of single unit, the gross capability of all kinds of unit in consideration interconnection two ends and peak-shaving capability can realize the analysis to interconnection power transmission power.For simplifying case study, accelerate computational speed, by all kinds of unit as Coal-fired Thermal Power, combustion gas thermoelectricity, wind-powered electricity generation, nuclear power etc. carry out unified Modeling respectively.To send, receiving-end system will all be considered as individual node, all kinds of unit all equivalence is single unit, equivalent unit capacity is the capacity sum of such each single unit, on system total load carries out that integration is connected on etc. value node, under this theory instructs, can the total operating cost target function of row write through system be: min C _gen+ C _carbon,

Wherein:

$C_{\mathrm{Gen}}=\underset{t\∈{\mathrm{\Ω}}_T}{\mathrm{\Σ}}\underset{k\∈{\mathrm{\Ω}}_K}{\mathrm{\Σ}}{c}_k^G\·(P_{t,k}^E+P_{t,k}^I)\·\mathrm{\Δt}$

$C_{\mathrm{Carbon}}=\underset{t\∈{\mathrm{\Ω}}_T}{\mathrm{\Σ}}\underset{k\∈{\mathrm{\Ω}}_K}{\mathrm{\Σ}}{c}^C\·e_k\·(P_{t,k}^E+P_{t,k}^I)\·\mathrm{\Δt}$

In formula, C _genfor the cost of electricity-generating of system; C _carbonfor the carbon emission cost of system; Ω _tfor optimizing period set; Ω _kfor the set of machine set type; c ^g _krepresent the unit cost of electricity-generating of kth class unit; c ^cthe Financial cost of representation unit carbon emission; e _krepresent the carbon emission that the generating of kLei unit unit produces; P ^e _t,kand P ⁱ _t,krepresent that interconnection sending end and receiving end kth class unit are exerted oneself at the meritorious of t respectively, subscript E and I represents sending end and receiving-end system respectively; The time span that Δ t problem of representation is analyzed.

Constraints comprises:

A, generation load Constraints of Equilibrium

$\underset{k\∈{\mathrm{\Ω}}_K}{\mathrm{\Σ}}{P}_{t,k}^E(1-{\mathrm{\σ}}_L)+\underset{k\∈{\mathrm{\Ω}}_K}{\mathrm{\Σ}}{P}_{t,k}^I=D_{\text{t}}$

In formula, σ _lfor the line loss rate of passway for transmitting electricity, D _tfor receiving-end system is at the load of t;

B, Climing constant

$-{\mathrm{\δ}}_k^D{P}_k^{\max }\≤P_{t,k}-P_{t-1,k}\≤{\mathrm{\δ}}_k^U{P}_k^{\max }$

In formula, δ ^d _k, δ ^u _kbe respectively the climbing rate representing kth class unit ascending, descending capacity, subscript max represents the installed capacity of all types of unit;

C, all kinds of unit output bound retrain

C1, for conventional power generation usage technology such as thermoelectricity, nuclear power and the reservoir type power plants with certain regulating power, to be constrained to:

$P_k^{\min }\≤P_{t,k}\≤P_k^{\text{max}}$

In formula, P ^min _krepresent the minimum load of all types of unit, P ^max _krepresent maximum installed capacity,

C2, for generation technologies such as wind-powered electricity generation, photovoltaic and plants without storage, to be constrained to:

$0{\≤P}_{t,k}\≤P_{t,k}^{\mathrm{FOR}}$

In formula, P ^fOR _t,kfor the predicted value of exerting oneself in t schedulable to kth class unit,

D, interconnection power transmission plan constraint

$f_{L,t}^{\min }\≤f_{L,t}\≤f_{L,t}^{\text{max}}$

In formula, f ^max _l,t, f ^min _l,tbe respectively the minimum and maximum performance number that t interconnection allows conveying, f _l,tfor passage is at the power transmission power of t,

Namely above target function and constraints constitute the optimizing and analyzing model of interconnection power transmission plan.

Second step, collects related data in a first step in systems in which, and system loading curve and wind power output prediction curve.Suppose Energy Base A by interconnection to certain load center B power transmission, wherein the maximum power load in B area is at about 8,000 ten thousand kilowatts, except A area, B area accepts other external power transmission totally 1,200 ten thousand kilowatts (invariable power pattern), and B regional power installation parameter, unit cost of electricity-generating and carbon emission coefficient is as shown in table 1.

Table 1 B regional power installation parameter

The specified power transmission power of A to B interconnection is 9,000,000 kilowatts, and A regional power installation parameter is as shown in table 2.

Table 2 tin alliance power transmission power supply installation parameter

Carbon emission cost is taken as 100 yuan/ton, and UHV transmission channel line loss rate is taken as 2%.Figure 2 shows that the typical day load curve at 15min interval, B regional load center, minimum load coefficient is 81%.Figure 3 shows that the prediction curve of a few days ago exerting oneself of sending end A ground and receiving end B ground wind-powered electricity generation.Set three kinds of typical power transmission plans, the perunit value of its each moment power transmission power is as shown in table 3.

The different power transmission plan of table 3

3rd step, to send receiving-end system cooperation cost minimum for target, given system loading and wind power output prediction curve being substituted in foregoing model, and applies the business Optimization Softwares such as Cplex and solve, combined optimization can be carried out to sending under different power transmission plan the operation of receiving-end system.According to each power transmission plan shown in table 3, the business Optimization Software solving-optimizing analytical models such as application Cplex, can in the hope of the contrast of the actual power curve of sending end wind-powered electricity generation under different power transmission plan as shown in Figure 4 (in Fig. 4 anti-peak regulation power-supply curve dope force curve with wind-powered electricity generation substantially overlap), system operation cost, carbon emission amount and wind electricity digestion situation are as shown in table 4.

The optimizing operation Comparative result of system under the different power transmission plan of table 4

4th step, by the comparative analysis to many alternative power transmission plans, selects the power transmission plan that operating cost is minimum.Result as can be seen from Fig. 4 and table 4, under given load curve and wind power output prediction curve, given three kinds of power transmissions in the works, the plan of anti-peak regulation power transmission can make system obtain minimum operating cost, sending end of dissolving to greatest extent area wind-powered electricity generation, and carbon emission amount is minimum.Therefore, can be the power transmission plan that interconnection formulates anti-peak regulation on the same day according to optimum results.

The above has made detailed description to the preferred embodiment of the present invention and embodiment by reference to the accompanying drawings; but the present invention is not limited to the above-described embodiment and examples; for those skilled in the art; without departing from the inventive concept of the premise; can also make some improvement and modification, these improve and modification also should be considered as protection scope of the present invention.

Claims (4)

1. improve an interconnection power transmission plan optimization method for the low carbonization level of electric power system, it is characterized in that, comprise the following steps:

The first step, set up optimizing and analyzing model:

The total operating cost of system is min C _gen+ C _carbon

Wherein:

$C_{\mathrm{Gen}}=\underset{{t\∈\mathrm{\Ω}}_T}{\mathrm{\Σ}}\underset{k\∈{\mathrm{\Ω}}_K}{\mathrm{\Σ}}{c}_k^G\·(P_{t,k}^E+P_{t,k}^I)\·\mathrm{\Δt}$

$C_{\mathrm{Carbon}}=\underset{{t\∈\mathrm{\Ω}}_T}{\mathrm{\Σ}}\underset{k\∈{\mathrm{\Ω}}_K}{\mathrm{\Σ}}{c}^C\·e_k\·(P_{t,k}^E+P_{t,k}^I)\·\mathrm{\Δt}$

In formula, C _genfor the cost of electricity-generating of system; C _carbonfor the carbon emission cost of system; Ω _tfor optimizing period set; Ω _kfor the set of machine set type; c ^g _krepresent the unit cost of electricity-generating of kth class unit; c ^cthe Financial cost of representation unit carbon emission; e _krepresent the carbon emission that the generating of kLei unit unit produces; P ^e _t,kand P ⁱ _t,krepresent that interconnection sending end and receiving end kth class unit are exerted oneself at the meritorious of t respectively, subscript E and I represents sending end and receiving-end system respectively; The time span that Δ t problem of representation is analyzed;

Constraints comprises:

A, generation load Constraints of Equilibrium

$\underset{k\∈{\mathrm{\Ω}}_k}{\mathrm{\Σ}}{P}_{t,k}^E(1-{\mathrm{\σ}}_L)+\underset{k\∈{\mathrm{\Ω}}_k}{\mathrm{\Σ}}{P}_{t,k}^I=D_t$

In formula, σ _lfor the line loss rate of passway for transmitting electricity, D _tfor receiving-end system is at the load of t;

B, Climing constant

${-\mathrm{\δ}}_k^D{P}_k^{\max }\≤P_{t,k}-P_{t-1,k}\≤{\mathrm{\δ}}_k^U{P}_k^{\max }$

In formula, δ ^d _k, δ ^u _kbe respectively the climbing rate representing kth class unit ascending, descending capacity, subscript max represents the installed capacity of all types of unit;

C, all kinds of unit output bound retrain

C1, for conventional power generation usage technology such as thermoelectricity, nuclear power and the reservoir type power plants with certain regulating power, to be constrained to:

$P_k^{\min }\≤P_{t,k}\≤P_k^{\max }$

In formula, P ^min _krepresent the minimum load of all types of unit, P ^max _krepresent maximum installed capacity,

C2, for generation technologies such as wind-powered electricity generation, photovoltaic and plants without storage, to be constrained to:

$0\≤P_{t,k}\≤P_{t,k}^{\mathrm{FOR}}$

In formula, P ^fOR _t,kfor the predicted value of exerting oneself in t schedulable to kth class unit,

D, interconnection power transmission plan constraint

$f_{L,t}^{\min }\≤f_{L,t}\≤f_{L,t}^{\max }$

In formula, f ^max _l,t, f ^min _l,tbe respectively the minimum and maximum performance number that t interconnection allows conveying, f _l,tfor passage is at the power transmission power of t,

Second step, collects the related data in the first step, and system loading curve and wind power output prediction curve, and designs interconnection power transmission to be selected plan;

3rd step, by the related data of collecting in second step, and system loading curve, wind power output prediction curve and interconnection power transmission plan to be selected substitute in the optimizing and analyzing model of the first step, and adopt Optimization Software to solve;

4th step, by the comparative analysis to many alternative power transmission plans, selects the power transmission plan that operating cost is minimum.

2. the interconnection power transmission plan optimization method of the low carbonization level of raising electric power system according to claim 1, it is characterized in that, when setting up optimizing and analyzing model, respectively modeling is carried out to all kinds of unit, to send, receiving-end system will all be considered as individual node, all kinds of unit all equivalence is single unit, and equivalent unit capacity is the capacity sum of such each single unit, on system total load carries out that integration is connected on etc. value node.

3. the interconnection power transmission plan optimization method of the low carbonization level of raising electric power system according to claim 1, it is characterized in that, in described 3rd step, obtain the comparison diagram of the actual power curve of sending end wind-powered electricity generation and the statistical form of system operation cost, carbon emission amount and wind electricity digestion situation under different power transmission plan.

4. the interconnection power transmission plan optimization method of the low carbonization level of raising electric power system according to claim 1 or 2 or 3, it is characterized in that, the described Optimization Software adopted in the 3rd step is Cplex software.