CN114564815B - Power system reliability and economy modeling method based on Brazier paradox effect - Google Patents
Power system reliability and economy modeling method based on Brazier paradox effect Download PDFInfo
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- CN114564815B CN114564815B CN202210041417.7A CN202210041417A CN114564815B CN 114564815 B CN114564815 B CN 114564815B CN 202210041417 A CN202210041417 A CN 202210041417A CN 114564815 B CN114564815 B CN 114564815B
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- G—PHYSICS
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- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F30/00—Computer-aided design [CAD]
- G06F30/20—Design optimisation, verification or simulation
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/008—Circuit arrangements for ac mains or ac distribution networks involving trading of energy or energy transmission rights
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- G—PHYSICS
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- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F2119/00—Details relating to the type or aim of the analysis or the optimisation
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J2203/00—Indexing scheme relating to details of circuit arrangements for AC mains or AC distribution networks
- H02J2203/20—Simulating, e g planning, reliability check, modelling or computer assisted design [CAD]
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J2300/00—Systems for supplying or distributing electric power characterised by decentralized, dispersed, or local generation
- H02J2300/20—The dispersed energy generation being of renewable origin
- H02J2300/28—The renewable source being wind energy
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- Y04—INFORMATION OR COMMUNICATION TECHNOLOGIES HAVING AN IMPACT ON OTHER TECHNOLOGY AREAS
- Y04S—SYSTEMS INTEGRATING TECHNOLOGIES RELATED TO POWER NETWORK OPERATION, COMMUNICATION OR INFORMATION TECHNOLOGIES FOR IMPROVING THE ELECTRICAL POWER GENERATION, TRANSMISSION, DISTRIBUTION, MANAGEMENT OR USAGE, i.e. SMART GRIDS
- Y04S10/00—Systems supporting electrical power generation, transmission or distribution
- Y04S10/50—Systems or methods supporting the power network operation or management, involving a certain degree of interaction with the load-side end user applications
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Abstract
The invention discloses a modeling method for reliability and economy of a power system based on a Blues paradox effect, which comprises the steps of evaluating loss caused by wind abandoning energy affecting the reliability of the power system and the return and cost in the whole power transmission construction, integrally evaluating the reliability and economy of a power grid through the change of the power transmission capacity, and finally finding out the optimal power transmission capacity, so that the power supply requirement, the return, the investment cost and the stable operation of the power grid are balanced.
Description
Technical Field
The invention belongs to the field of power system evaluation, and particularly relates to a power system reliability and economy modeling method based on a Brazier paradox effect.
Background
Wind energy is the most potential renewable energy source capable of being developed on a large scale at present, and is paid more attention to the advantages of convenient development and utilization, low cost and the like. Wind power is influenced by meteorological conditions and environmental factors, and has strong randomness and intermittence, so that the balance between power supply and demand and the stable operation and scheduling of a power system are brought with serious challenges by large-scale wind power access to a power grid. Many factors determine the magnitude of wind energy in proportion to the power system, but the magnitude of the wind power transmission capacity is the most important element. Therefore, modeling of the reliability and economy of the power system by considering the wind energy capacity is necessary for resource allocation and wind energy scheduling, the reliability of the power system is improved after evaluation, the wind energy receiving capacity of the power system is improved, the planned maintenance of a wind power plant is guided, and the required energy storage electric energy is reduced, so that the method has great economic significance.
A large number of wind turbines are integrated into a power system, and the wind energy is seriously abandoned due to the characteristics of the wind energy, so that huge losses are brought. How to balance the contradiction between wind energy and a power grid, and increasing the scale of wind energy grid connection under the condition of ensuring the safe operation of the power grid is a key problem at present. When implementing the wind energy capacity expansion plan, according to the system reliability theory, adding a new link or improving the power transmission capacity of the existing link can obviously increase the system reliability. However, when the capacity is increased to a certain extent, the capacity of the whole system is reduced and even the synchronization characteristic of the system is destroyed according to the Brix paradox, so that the reliability is greatly affected. The trigger point of reduced trigger reliability is highly correlated with existing topology and load distribution parameters. It has been shown in the literature that removing certain links improves the synchronisation characteristics and transmission capacity of the power system, and that increasing or adding power elements has some effect on the capacity and synchronisation of the system, thereby altering the reliability of the power system. The power system needs a great deal of cost investment to construct, and when wind energy is integrated into the power system, the reliability of the power system is ensured while the investment cost of a power transmission network is reduced, so that the problem needs to be solved urgently. Meets the regulation of power supply reliability, improves the running reliability of the system, ensures economy and can not reach the optimal indexes basically at the same time. Therefore, the modeling of the power system by considering the wind energy transmission capacity can provide basic information for investment of the power grid, and has very important theoretical and practical significance for improving safety and stability of the power grid.
Disclosure of Invention
In view of the above, the present invention aims to provide a method for modeling reliability and economy of a power system based on the bris paradox effect, which can overcome the defects of the prior art, and build a model for modeling reliability and economy of the power system considering the power transmission capacity of wind energy, so as to obtain the power transmission capacity which can optimize both the reliability and economy of the power system containing wind energy.
The invention aims at realizing the following technical scheme:
the invention provides a modeling method for reliability and economy of a power system based on the Boolean paradox effect, which comprises the following steps:
s1: obtaining electric quantity benefits brought in the wind energy transmission process;
s2: determining the size of abandoned wind energy caused by blocking of a power transmission link, which influences reliability;
s3: calculating the power transmission cost when the power transmission link is constructed;
s4: establishing a reliability and economical efficiency comprehensive evaluation model considering the wind energy transmission capacity under the Brix paradox effect;
s5: and calculating the optimal transmission capacity according to the model.
Further, in the step S1, in the process of the wind energy transmission link to the load center, a calculation formula of electric quantity gain caused by wind energy power is as follows:
R(L)＝C P E wind
wherein R (L) is electric quantity income; c (C) P The unit electricity price for delivering the wind energy and electricity quantity; e (E) wind For delivering the total electric quantity, the calculation formula is as follows:
wherein n is the life of the power transmission system; p (P) wind (t) is the wind power delivered at t; the delta T is the output time of the wind turbine, and the calculation formula is as follows:
wherein P is line The power transmission capacity is wind energy; and P (t) is the actual measured wind energy power when t.
In the step S2, when the wind power exceeds the transmission capacity to cause blockage, the calculation formula is as follows:
wherein E is loss (L) is wind abandoning energy; k (K) q The unit electricity price is the abandoned wind energy; p (P) loss And (t) is the wind curtailed power at t.
In the step S3, the power transmission cost includes costs such as construction materials and labor costs, and the calculation formula is as follows:
C(L)＝K l P line L
wherein, C (L) is the transmission cost; k (K) l The cost of building unit length and capacity for the power transmission link; l is the transmission link length.
Further, in the step S4, the calculation formula of the evaluation model of the comprehensive economy and reliability of the transmission capacity through the electric quantity income, the wind curtailment energy and the cost is as follows:
S(L)＝R(L)-E loss (L)-C(L)
wherein S (L) is comprehensive benefit.
The invention has the beneficial effects that: the invention provides a modeling method for reliability and economy of a power system containing wind energy by considering power supply requirements, wind energy benefits, investment cost and power system reliability. When the capacity of the transmission link is increased, the abandoned wind energy is gradually reduced, but the transmission construction cost is always increased, so that the key point is to find the optimal transmission capacity with more transmission electric quantity, less investment and good reliability. The economical aspect is embodied by the wind energy income and the construction cost in the transmission process of the power transmission link, and the reliability aspect is embodied by the wind energy waste. And (3) establishing a reliability and economy modeling model considering the wind energy transmission capacity, and finally obtaining the optimal transmission capacity meeting the power supply requirement.
Drawings
In order to make the objects, technical solutions and advantageous effects of the present invention more clear, the present invention provides the following drawings for description:
FIG. 1 is an overall flow chart;
FIG. 2 is a grid rack block diagram;
FIG. 3 is a graph of the dynamic relationship between the set of expansions and the reliability based on the Boolean paradox effect;
fig. 4 is a graph of transmission capacity versus comprehensive revenue.
Detailed Description
Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings.
According to the invention, through a regional power grid, which comprises 9 wind energy fields, the total capacity of a fan loader is 1493.8MW, and the reliability and economy of the power grid are evaluated by adopting electric quantity income, power transmission cost and abandoned wind energy, so that the optimal power transmission capacity is obtained. As shown in fig. 1, the modeling method for reliability and economy of the electric power system based on the brix paradox effect specifically includes:
step 1, obtaining electric quantity benefits brought in the wind energy transmission process;
the grid structure of the power grid is shown in fig. 2, and in the process of the wind energy transmission link to the load center, the calculation formula of the electric quantity benefit caused by wind energy power is as follows:
R(L)＝C P E wind
wherein R (L) is electric quantity income; c (C) P For delivering the unit electricity price of the wind energy electric quantity, the value is 60 yuan MWh -1 ；E wind For delivering the total electric quantity, the calculation formula is as follows:
wherein n is the service life of the power transmission system and the value is 20; p (P) wind (t) is the wind power delivered at t; the delta T is the output time of the wind turbine, and the calculation formula is as follows:
wherein P is line The power transmission capacity is wind energy; and P (t) is the actual measured wind energy power when t.
Adding new links or increasing the capacitance of existing links can significantly increase system reliability according to system reliability theory. However, when the capacity is increased to a certain extent, the capacity of the whole system is reduced and even the synchronization characteristic of the system is destroyed according to the Brix paradox, so that the reliability is greatly affected. The trigger point with reduced trigger reliability and the existing topological structure and load distribution parameters are all providedHighly correlated. Increasing or increasing the capacity and synchronization of the power elements to the system may improve the synchronization characteristics and capacitance of the power system, thereby changing the reliability of the power system. As shown in fig. 3, E is a capacity-expanding link set, adding a link or expanding capacity is regarded as an operation, and 0 to n in fig. 1 are operation sequences; r is R i For the i-th operation power system reliability. The calculated reliability R follows the sequence of operations from R 0 Change to R n . Operation m in the operation sequence is a trigger point for a sudden change in reliability. Before operation m, R gradually increases, indicating that the reliability of the system increases with the increase of the power element, but after operation m, the system becomes less in capacitance and out of step, thereby R m To R n From large to small.
Step 2, determining the size of abandoned energy caused by blocking of a power transmission link, which affects reliability;
when the transmission link capacity E increases, the reliability R is greater than R 0 To R m A maximum value is reached in the process of (a). Continue to increase to R n When wind energy exceeds the transmission capacity and causes blockage, waste wind energy is generated, and the calculation formula is as follows:
wherein E is loss (L) is wind abandoning energy; k (K) q The unit electricity price of the abandoned wind energy is 500 yuan MWh -1 ；P loss And (t) is the wind curtailed power at t.
Step 3, calculating the power transmission cost when the power transmission link is constructed;
the transmission cost comprises the cost of construction materials, labor cost and the like, and the calculation formula is as follows:
C(L)＝K l P line L
wherein, C (L) is the transmission cost; k (K) l Building a unit length for a power transmission linkThe cost of the degree and the capacity is 100 ten thousand yuan MW 100km -1 The method comprises the steps of carrying out a first treatment on the surface of the L is the length of the transmission link and the value is 200km.
Step 4, establishing a reliability and economical efficiency modeling model considering the wind energy transmission capacity;
through the evaluation model of electric quantity income, abandoned wind energy and cost, comprehensive economy and reliability of the power transmission capacity, the calculation formula of the comprehensive income is as follows:
S(L)＝R(L)-E loss (L)-C(L)
wherein S (L) is comprehensive benefit.
And Step 5, calculating the optimal transmission capacity according to the model.
As shown in FIG. 4, the curve of the wind energy transmission capacity and the comprehensive profit is that only investment cost is put into the beginning, so that the profit is negative, when P line The overall gain is also maximized when the capacity is gradually increased to 930MW, and the gain is decreased instead when the capacity is gradually increased again. The comprehensive benefit comprises the loss caused by the abandoned wind, so that the reliability and the economy are relatively optimal when the comprehensive benefit is maximum.
The invention is innovative in that a modeling method for reliability and economy of the power system is designed based on the consideration of wind energy transmission capacity under the Brix paradox effect. The power supply requirement, the cost, the income and the loss caused by wind abandoning are all calculated, the reliability and the economy of the power system are integrally evaluated, and finally, the most suitable power transmission capacity is determined, so that the reliability and the economy of the power system are satisfied under the balanced condition.
Finally, it is noted that the above-mentioned preferred embodiments are only intended to illustrate rather than limit the invention, and that, although the invention has been described in detail by means of the above-mentioned preferred embodiments, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the scope of the invention as defined by the appended claims.
Claims (1)
1. A modeling method for reliability and economy of an electric power system based on the Booth paradox effect is characterized by comprising the following steps: the method comprises the following steps:
s1: obtaining electric quantity benefits brought in the wind energy transmission process;
s2: determining the size of abandoned wind energy caused by blocking of a power transmission link, which influences reliability;
s3: calculating the power transmission cost when the power transmission link is constructed;
s4: establishing a reliability and economical efficiency comprehensive evaluation model considering the wind energy transmission capacity under the Brix paradox effect;
s5: calculating optimal power transmission capacity according to the model;
in the step S1, in the process of the wind energy transmission link to the load center, the calculation formula of the electric quantity gain caused by wind energy power is as follows:
R(L)＝C P E wind
wherein R (L) is electric quantity income; c (C) P The unit electricity price for delivering the wind energy and electricity quantity; e (E) wind For delivering the total electric quantity, the calculation formula is as follows:
wherein n is the life of the power transmission system; p (P) wind (t) is the wind power delivered at t; the delta T is the output time of the wind turbine, and the calculation formula is as follows:
wherein P is line The power transmission capacity is wind energy; actually measuring wind energy power when P (t) is t;
in the step S2, when the wind energy exceeds the transmission capacity to cause blockage, the wind energy is abandoned, and the calculation formula is as follows:
wherein E is loss (L) is wind abandoning energy; k (K) q The unit electricity price is the abandoned wind energy; p (P) loss (t) when t is the wind power;
in the step S3, the transmission cost comprises construction materials, labor cost and other costs, and the calculation formula is as follows:
C(L)＝K l P line L
wherein, C (L) is the transmission cost; k (K) l The cost of building unit length and capacity for the power transmission link; l is the length of the transmission link;
in the step S4, the evaluation model calculation formula of the comprehensive economy and reliability of the power transmission capacity through electric quantity income, wind curtailment energy and cost is as follows:
S(L)＝R(L)-E loss (L)-C(L)
wherein S (L) is comprehensive benefit.
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| CN110034561A (en) * | 2019-05-15 | 2019-07-19 | 长沙理工大学 | A kind of wind farm energy storage capacity optimization method based on cloud energy storage lease service |
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| CN103259285B (en) * | 2013-05-03 | 2015-04-29 | 国家电网公司 | Method for optimizing short running of electric power system comprising large-scale wind power |
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|---|---|---|---|---|
| US8468040B1 (en) * | 2004-05-14 | 2013-06-18 | Joseph Jolly Hayden | System and method for identifying and upgrading a transmission grid |
| CN103078338A (en) * | 2013-01-13 | 2013-05-01 | 东北电力大学 | Energy storage system configuration method for improving utilization level of wind energy of wind power plant |
| CN105528466A (en) * | 2014-09-28 | 2016-04-27 | 国家电网公司 | Wind power optimal planning modeling method considering adaptability and economy of power system |
| CN110034561A (en) * | 2019-05-15 | 2019-07-19 | 长沙理工大学 | A kind of wind farm energy storage capacity optimization method based on cloud energy storage lease service |
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