Carbon emission reduction factor calculation method and system considering green electricity medium and long term contract constraint

Abstract

The invention discloses a carbon emission reduction factor calculation method and system considering green power medium and long term contract constraints. The method comprises the following steps: reasonably decomposing the total amount of green power medium and long term contracts into all time periods; constructing an inter-region optimization scheduling model considering the green electricity transaction, wherein the inter-region optimization scheduling model comprises a target function for minimizing the total cost of the system and a plurality of constraint conditions; the plurality of constraint conditions comprise a partition balance constraint, a cross-regional tie line constraint, a thermal power generating unit constraint, a wind power generating unit constraint and a green power medium and long term contract constraint; and calculating a carbon emission reduction factor through carbon flow tracking according to a scheduling result of the inter-region optimization scheduling model considering the green electricity transaction. According to the method, the inter-region optimization scheduling model considering the green power transaction is constructed, and the carbon emission reduction factor is obtained through carbon flow tracking, so that the power generation cost of the system is reduced, and new energy consumption is promoted.

Description

Technical Field

[0001] The present invention relates to a method and system for calculating carbon emission reduction factors taking into account the constraints of green electricity medium- and long-term contracts, and belongs to the field of carbon emission reduction in power systems. Background Art

[0002] In recent years, China's renewable energy power generation has flourished under the encouragement of national policies. High-level grid connection of renewable energy is an inevitable trend for the future development of the power system. Against this background, the development of green power trading plays an important role in achieving the "dual carbon" goals. The low-carbon transformation of electricity is the key to achieving the "dual carbon" goals in my country. In the process of low-carbon transformation, it is necessary not only to overcome scientific and technological breakthroughs, but also to establish a sound and complete market mechanism as the basis for low-carbon transformation.

[0003] At present, green electricity transactions are usually traded in the market in the form of medium- and long-term contracts. Since medium- and long-term contracts in green electricity transactions usually involve a long time span, this means that there are uncertainties in factors such as price, supply, and market environment when the contract is signed. Since the supply of green electricity depends on factors such as climate and season, its price volatility is large, which poses a challenge to the precise demand for supply and demand matching. Therefore, a method is needed to decompose these medium- and long-term contracts to make them more flexible and operational, and to effectively respond to market fluctuations.

[0004] With the continuous advancement of green energy transformation and the accelerated development of the green electricity consumption market, the green electricity market will become an important part of the national unified electricity market. At present, green electricity transactions are mostly carried out in a medium- and long-term manner. Unlike traditional electricity such as thermal power generation, green electricity not only contains the value of electricity, but its environmental value cannot be ignored. At present, it is generally believed that the carbon emissions of green electricity in the production process are approximately zero. With the official launch of the national carbon market in 2020 and the implementation of a series of carbon reduction policies, the relationship between green electricity and carbon offsets has become very close. How to reasonably use green electricity to guide carbon emission reduction has important environmental value. Summary of the invention

[0005] The purpose of the present invention is to provide a method and system for calculating carbon emission reduction factors taking into account the constraints of green electricity medium- and long-term contracts, reasonably decompose the total amount of green electricity medium- and long-term contracts into various time periods, construct an inter-regional optimization scheduling model taking into account green electricity transactions, and obtain carbon emission reduction factors through carbon flow tracking, so as to reduce the system power generation cost and promote the consumption of new energy.

[0006] In order to achieve the above-mentioned purpose, the present invention provides a method for calculating carbon emission reduction factors taking into account the constraints of green electricity medium- and long-term contracts, comprising the following steps:

[0007] The calculation method of carbon emission reduction factor considering the constraints of green electricity medium- and long-term contracts includes the following steps:

[0008] Reasonably decompose the total amount of green electricity medium- and long-term contracts into different time periods;

[0009] Construct an inter-regional optimal dispatch model considering green electricity trading, including the objective function of minimizing the total system cost and several constraints;

[0010] The several constraints mentioned include regional balance constraints, cross-regional interconnection line constraints, thermal power unit constraints, wind power unit constraints and green power medium- and long-term contract constraints;

[0011] The cross-regional tie line constraints include DC tie line transmission power constraints, DC tie line transmission power ramp constraints, DC tie line network loss constraints, AC tie line transmission power, AC tie line transmission power constraints, and AC tie line network loss constraints;

[0012] According to the dispatch results of the inter-regional optimal dispatch model considering green electricity trading, the carbon emission reduction factor is calculated through carbon flow tracking.

[0013] Further optimization, the steps to reasonably decompose the total amount of green power medium- and long-term contracts into various time periods are as follows:

[0014] The daily output curve left for the units participating in the market bidding is expressed as follows:

[0015]

[0016] In the formula, The load forecast curve for each day of the next year is predicted by the trading center at the beginning of the year, P MT (t) is the daily output curve reserved for the units participating in the market bidding, P NMT (t) is the output curve of the units not participating in the market, and t is time.

[0017] The proportion of the contracted power of each green generator group to the total power generation of the generator groups participating in the market bidding is expressed as follows:

[0018]

[0019] In the formula, k j Q is the proportion of the contracted power of the jth green generator group to the total power generation of the generator groups participating in the market bidding, p is the total annual electricity consumption, represents the total power generation participating in the market bidding, is the total amount of contracts signed for the jth green power unit.

[0020] The decomposition volume of green power medium- and long-term contracts in each period of the trading day is expressed by the formula as follows:

[0021]

[0022] In the formula, is the green electricity contract decomposition amount of the j-th green power unit in period t.

[0023] It is further preferred that the inter-regional optimization scheduling model considering green electricity trading is designed to complete the renewable energy consumption responsibility weight index, and minimize the total power generation cost of the generator set and the inter-regional transmission cost of the regional power grid as the optimization goal, and construct an objective function that minimizes the total system cost.

[0024] The total system cost includes the power generation cost C gen , Carbon trading costs C car , the transmission cost of inter-regional interconnection lines C tra , network loss cost C was and the cost of purchasing excess consumption C tgc :

[0025]

[0026]

[0027]

[0028]

[0029]

[0030] Where T represents the total number of time periods considered; R represents the total number of regional power grids; N r represents the total number of units in the regional power grid r; K represents the total number of sections; represents the electricity cost of the i-th generator set; represents the carbon trading cost of the i-th generator; is the startup cost of thermal power unit i in period t; It indicates the power of the i-th thermal power unit in the k-th segment of time period t; α i,k,t N represents the declared price of the kth electricity energy of the i-th thermal power unit in time period t; Er and N GEr They represent the total number of thermal power units and new energy units that provide power supply to the regional power grid r; represents the power of the i-th green generator set in the k-th segment of time period t; γ i,k,t represents the price quoted by the i-th green power unit in the k-th period of time t; is the carbon emission intensity of the i-th thermal power unit, indicating the carbon emission corresponding to unit power generation, represents the benchmark carbon emission intensity corresponding to the i-th thermal power unit; β c is the carbon price; L represents the total number of inter-regional contact lines; represents the transmission price of the lth inter-regional regional grid tie line; and They represent the traditional energy and new energy power transmitted by the lth cross-regional interconnection line in time period t; C L,l represents the network loss penalty factor or network loss rate of the lth inter-regional tie line; and Respectively represent the network loss of AC tie line and DC tie line; inter-regional tie line includes inter-regional DC tie line and inter-regional AC tie line, N dc is the set of inter-regional DC interconnection lines; N ac It is a collection of inter-regional communication lines; is the excess consumption of the regional power grid or the market price of green certificates; It is the excess consumption amount or the electricity amount corresponding to the green certificate purchased by the regional power grid r during the assessment period T.

[0031] Furthermore, the partition balance constraint is expressed as follows:

[0032]

[0033]

[0034]

[0035] In the formula, and They represent the total winning bid output of the i-th thermal power unit and the i-th new energy unit in the regional power grid r in period t, including the contract decomposed power; and They represent the injected traditional energy and new energy power of the lth tie line in the regional power grid r in period t, respectively. Positive numbers represent the power flowing into the regional power grid r. D j,r,t N represents the load forecast value of load j in regional power grid r during period t; Er and N GEr They represent thermal power units and new energy units that provide power to the regional power grid r, including point-to-grid power generating units that are not located in the regional power grid r; N Tr N represents the set of tie lines associated with the regional power grid r; Dr represents the total number of loads in the regional power grid r; T l,t represents the transmission power of the lth tie line. i,t represents the start and stop status of the i-th thermal power unit in the regional power grid r during period t; represents the maximum technical output of the i-th thermal power unit in time period t; represents the corresponding positive reserve capacity demand to the regional power grid r. represents the minimum technical output of the i-th thermal power unit in time period t; Represents the negative reserve capacity demand corresponding to the regional power grid r.

[0036] Furthermore, the partitioned renewable energy consumption responsibility constraint is expressed as follows:

[0037]

[0038]

[0039] Where μ is the non-hydro renewable energy consumption responsibility weight of a certain region. tgc,max Indicates the tradable excess consumption or upper limit of green certificates; It represents the output of the i-th renewable energy unit in the regional power grid r in the k-th segment of time period t.

[0040] Furthermore, the constraint of the inter-regional DC tie line is expressed as follows:

[0041]

[0042]

[0043]

[0044]

[0045] In the formula, and They represent the maximum and minimum transmission power of the lth DC tie line in time period t, Represents the transmission power of the lth DC tie line in time period t. and 0-1 variables representing up and down power, respectively; It represents the minimum climbing transmission power of the transmission line, Indicates the maximum climbing transmission power of the transmission line. It represents the linear proportionality coefficient of the network loss of the lth DC tie line.

[0046] Furthermore, the inter-regional AC line constraint is expressed as follows:

[0047]

[0048]

[0049]

[0050] In the formula represents the power transfer distribution factor of the i-th generator set in the regional grid r to the l-th AC tie line, represents the power transfer distribution factor of the regional grid j load to the lth AC tie line, represents the power transfer distribution factor of the DC tie line to the AC tie line of the regional power grid, G j-a It represents the power transfer distribution factor of load j in regional power grid r to the AC tie line. and They represent the maximum and minimum transmission power of the lth AC tie line in period t respectively; represents the transmission power of the lth AC tie line in period t, P i,r,t It represents the power generation of the i-th generator set in the regional power grid r in time period t. It represents the linear proportionality coefficient of the network loss of the lth DC tie line.

[0051] Furthermore, the constraints of the traditional thermal power unit are expressed as follows:

[0052]

[0053]

[0054]

[0055]

[0056]

[0057]

[0058] Where P i,t represents the power generation of the i-th thermal power unit in time period t; P i,min represents the minimum output of the ith thermal power unit, P i,k,t It represents the output of the kth segment of the output curve of the i-th thermal power unit in the t-th period. i,t is a 0-1 variable that adjusts the power of the i-th thermal power unit in the t-th period, indicating the operating status of the i-th thermal power unit; x i,v Indicates the power generation status of the thermal power unit at the initial moment; Represents the maximum power generation of the i-th thermal power unit. represents the ramp power of the i-th thermal power unit, T D and T U Respectively represent the maximum and minimum start and stop times.

[0059] Furthermore, the green electricity medium- and long-term contract constraints are expressed as follows:

[0060]

[0061] In the formula, is the green power contract decomposition amount of the jth green power unit in period t, represents the power generation of the jth green power unit in period t, It represents the maximum power generation of the jth green power unit in period t.

[0062] The scheduling results of the inter-regional optimization scheduling model considering green electricity trading are input into the carbon flow tracking model to calculate the indirect carbon emissions of each node.

[0063] Furthermore, the carbon potential matrix E is established N The calculation formula is expressed as:

[0064]

[0065] Where N is the total number of nodes and Q is the number of power generation nodes. Node active flux matrix P N is an N-dimensional diagonal matrix; the branch power distribution matrix P B(N×N) is a sparse matrix with N rows and N columns; P G T P G The transposed matrix of the unit injection distribution matrix P G Element P Gi is the power injected by the generator set at the i-th node, and the generator set injection distribution matrix dimension is Q×N; the generator set carbon emission intensity vector E G Medium E Ji is the carbon emission intensity of the generator set at the i-th node, and the dimension of the carbon emission intensity vector of the generator set is Q×1.

[0066] Furthermore, define the load carbon flow rate vector R L , the dimension is M×1, expressed as:

[0067] R L =P L ×E N

[0068] Where M is the number of load nodes, and the load distribution matrix P L (dimension is M×N), if the jth node is the mth (m=1,2,…,M)th node with load, and the active load is P, then the load P of the jth node L(m,j) =P, otherwise the load of the jth node is P L(m,j) =0.

[0069] Furthermore, the carbon emission vector E is defined as L , the dimension is M×1, expressed as:

[0070] EL =R L ×t

[0071] Furthermore, the carbon emission reduction factor C is defined as G , expressed as:

[0072]

[0073] In the formula, C Gj is the carbon emission reduction factor of the jth load node, E Lj is the carbon emission of the jth load node before using green electricity, E L ' j Carbon emissions after using green electricity for the jth load node.

[0074] Furthermore, the calculation methods of emission reduction factors for green power companies and power users are different due to the different transaction forms of green power trading objects. When calculating the carbon emission reduction factor for a single green power company and a single green power user, the formula is:

[0075]

[0076] In the formula, C g_grei is the emission reduction factor of the i-th green power enterprise conducting the green power transaction, C g-loadj is the emission reduction factor of the jth green electricity user who conducts the green electricity transaction.

[0077] Furthermore, when calculating the carbon emission reduction factor when multiple green power companies trade with a single green power user, the formula is:

[0078]

[0079]

[0080] In the formula, Q ij is the green electricity transaction volume between the i-th green electricity enterprise and the j-th green electricity user (node ​​or regional power grid); Q kj is the green electricity transaction volume between the kth green electricity enterprise and the jth green electricity user; n is the total number of green electricity enterprises participating in the green electricity transaction; C g_grek is the emission reduction factor of the kth green power enterprise;

[0081] Furthermore, when calculating the carbon emission reduction factor when a single green power enterprise conducts transactions with multiple green power users, the formula is expressed as:

[0082]

[0083]

[0084] Where m is the number of green electricity users who conduct green electricity transactions with the i-th green electricity enterprise.

[0085] The present invention provides a carbon emission reduction factor calculation system taking into account the constraints of green electricity medium- and long-term contracts. The system includes a memory, a processor, and a computer program stored in the memory. When the computer program is executed by the processor, it implements the various steps of the carbon emission reduction factor calculation method taking into account the constraints of green electricity medium- and long-term contracts as described above.

[0086] The present invention provides a computer-readable storage medium storing a computer program, which, when executed by a processor, implements the various steps of the above-mentioned method for calculating a carbon emission reduction factor taking into account constraints of green electricity medium- and long-term contracts.

[0087] Compared with the prior art, the present invention has the following characteristics and beneficial effects:

[0088] The present invention decomposes the medium- and long-term green electricity contracts into various time periods while taking the load curve into consideration, establishes an inter-regional optimization scheduling model taking into consideration green electricity transactions, and takes into consideration cross-regional green electricity transactions when there are AC and DC transmission lines between regions. At the same time, the carbon emission costs and the weighted costs of renewable energy consumption responsibility are introduced, and the environmental value of green electricity is reflected through the green electricity carbon emission offset mechanism. The environmental benefits of green electricity transactions under different transaction entities are characterized through the calculation of carbon emission reduction factors. BRIEF DESCRIPTION OF THE DRAWINGS

[0089] Figure 1 It is a flow chart of the present invention. DETAILED DESCRIPTION

[0090] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0091] Example 1

[0092] like Figure 1 As shown in the figure, the calculation method of carbon emission reduction factor considering the constraints of green electricity medium- and long-term contracts includes the following steps:

[0093] Reasonably decompose the total amount of green electricity medium- and long-term contracts into different time periods;

[0094] Construct an inter-regional optimal dispatch model considering green electricity trading, including the objective function of minimizing the total system cost and several constraints;

[0095] The several constraints mentioned include regional balance constraints, cross-regional interconnection line constraints, thermal power unit constraints, wind power unit constraints and green power medium- and long-term contract constraints;

[0096] The cross-regional tie line constraints include DC tie line transmission power constraints, DC tie line transmission power ramp constraints, DC tie line network loss constraints, AC tie line transmission power, AC tie line transmission power constraints, and AC tie line network loss constraints;

[0097] According to the dispatch results of the inter-regional optimal dispatch model considering green electricity trading, the carbon emission reduction factor is calculated through carbon flow tracking.

[0098] The inter-regional optimization scheduling model considering green electricity trading aims to complete the renewable energy consumption responsibility weight index and minimize the total cost of unit power generation and the transmission cost between regional power grids. It assigns the generator cost curve and load curve, the decomposition of each time period of the green electricity medium- and long-term contracts, and the maximum and minimum values ​​of each generator set, each cross-regional interconnection line, and the transmission line within the region. Through the inter-regional optimization scheduling model, the output of each generator set and the transmission power of each line are obtained.

[0099] In this embodiment, the steps of dividing the generator sets into green power sets and thermal power sets and reasonably decomposing the total amount of green power medium- and long-term contracts into various time periods are as follows:

[0100] The daily output curve left for the units participating in the market bidding is expressed as follows:

[0101]

[0102] In the formula, The load forecast curve for each day of the next year is predicted by the trading center at the beginning of the year, P MT (t) is the daily output curve reserved for the units participating in the market bidding, P NMT (t) is the output curve of the units not participating in the market, and t is time.

[0103] The proportion of the contracted power of each green generator group to the total power generation of the generator groups participating in the market bidding is expressed as follows:

[0104]

[0105] In the formula, k j Q is the proportion of the contracted power of the jth green generator group to the total power generation of the generator groups participating in the market bidding, p is the total annual electricity consumption, represents the total power generation participating in the market bidding, is the total amount of contracts signed for the jth green power unit.

[0106] The decomposition volume of green power medium- and long-term contracts in each period of the trading day is expressed by the formula as follows:

[0107]

[0108] In the formula, is the green electricity contract decomposition amount of the j-th green power unit in period t.

[0109] In this embodiment, the inter-regional optimization scheduling model considering green electricity trading is designed to complete the renewable energy consumption responsibility weight index, and the total power generation cost of the generator set and the inter-regional transmission cost of the regional power grid are minimized as the optimization goals, thereby constructing an objective function that minimizes the total system cost.

[0110] The total system cost includes the power generation cost C gen , Carbon trading costs C car , the transmission cost of inter-regional interconnection lines C tra , network loss cost C was and the cost of purchasing excess consumption C tgc :

[0111]

[0112]

[0113]

[0114]

[0115]

[0116] Where T represents the total number of time periods considered; R represents the total number of regional power grids; N r represents the total number of units in the regional power grid r; K represents the total number of sections; represents the electricity cost of the i-th generator set; represents the carbon trading cost of the i-th generator; is the startup cost of thermal power unit i in period t; It indicates the power of the i-th thermal power unit in the k-th segment of time period t; α i,k,t N represents the declared price of the kth electricity energy of the i-th thermal power unit in time period t; Er and N GEr They represent the total number of thermal power units and new energy units that provide power supply to the regional power grid r; represents the power of the i-th green generator set in the k-th segment of time period t; γ i,k,t represents the price quoted by the i-th green power unit in the k-th period of time t; is the carbon emission intensity of the i-th thermal power unit, indicating the carbon emission corresponding to unit power generation, represents the benchmark carbon emission intensity corresponding to the i-th thermal power unit; β c is carbon. Since the time scale of carbon trading is relatively long, the carbon price is assumed to be constant; L represents the total number of cross-regional contact lines; represents the transmission price of the lth inter-regional regional grid tie line; and They represent the traditional energy and new energy power transmitted by the lth cross-regional interconnection line in time period t; C L,l represents the network loss penalty factor or network loss rate of the lth inter-regional tie line; and Respectively represent the network loss of AC tie line and DC tie line; inter-regional tie line includes inter-regional DC tie line and inter-regional AC tie line, N dc is the set of inter-regional DC interconnection lines; N ac It is a collection of inter-regional communication lines; is the excess consumption of the regional power grid or the market price of green certificates; It is the excess consumption amount or the electricity amount corresponding to the green certificate purchased by the regional power grid r during the assessment period T.

[0117] Furthermore, the partition balance constraint is expressed as follows:

[0118]

[0119]

[0120]

[0121] In the formula, and They represent the total winning bid output of the i-th thermal power unit and the i-th new energy unit in the regional power grid r in period t, including the contract decomposed power; and They represent the injected traditional energy and new energy power of the lth tie line in the regional power grid r in period t, respectively. Positive numbers represent the power flowing into the regional power grid r. D j,r,t N represents the load forecast value of load j in regional power grid r during period t; Er and N GEr They represent thermal power units and new energy units that provide power to the regional power grid r, including point-to-grid power generating units that are not located in the regional power grid r; N Tr N represents the set of tie lines associated with the regional power grid r; Dr represents the total number of loads in the regional power grid r; T l,t represents the transmission power of the lth tie line. i,t represents the start and stop status of the i-th thermal power unit in the regional power grid r during period t; represents the maximum technical output of the i-th thermal power unit in time period t; represents the corresponding positive reserve capacity demand to the regional power grid r. represents the minimum technical output of the i-th thermal power unit in time period t; Represents the negative reserve capacity demand corresponding to the regional power grid r.

[0122] Furthermore, the partitioned renewable energy consumption responsibility constraint is expressed as follows:

[0123]

[0124]

[0125] Where μ is the non-hydro renewable energy consumption responsibility weight of a certain region. tgc,max Indicates the tradable excess consumption or upper limit of green certificates; It represents the output of the i-th renewable energy unit in the regional power grid r in the k-th segment of time period t.

[0126] Furthermore, the constraint of the inter-regional DC tie line is expressed as follows:

[0127]

[0128]

[0129]

[0130]

[0131] In the formula, and They represent the maximum and minimum transmission power of the lth DC tie line in time period t, Represents the transmission power of the lth DC tie line in time period t. and 0-1 variables representing up and down power, respectively; It represents the minimum climbing transmission power of the transmission line, Indicates the maximum climbing transmission power of the transmission line. It represents the linear proportionality coefficient of the network loss of the lth DC tie line.

[0132] Furthermore, the inter-regional AC line constraint is expressed as follows:

[0133]

[0134]

[0135]

[0136] In the formula represents the power transfer distribution factor of the i-th generator set in the regional grid r to the l-th AC tie line, represents the power transfer distribution factor of the regional grid j load to the lth AC tie line, represents the power transfer distribution factor of the DC tie line to the AC tie line of the regional power grid, G j-a It represents the power transfer distribution factor of load j in regional power grid r to the AC tie line. and They represent the maximum and minimum transmission power of the lth AC tie line in period t respectively; represents the transmission power of the lth AC tie line in period t, P i,r,t It represents the power generation of the i-th generator set in the regional power grid r in time period t. It represents the linear proportionality coefficient of the network loss of the lth DC tie line.

[0137] Furthermore, the constraints of the traditional thermal power unit are expressed as follows:

[0138]

[0139]

[0140]

[0141]

[0142]

[0143]

[0144] Where P i,t represents the power generation of the i-th thermal power unit in time period t; P i,min represents the minimum output of the ith thermal power unit, P i,k,t It represents the output of the kth segment of the output curve of the i-th thermal power unit in the t-th period. i,t is a 0-1 variable that adjusts the power of the i-th thermal power unit in the t-th period, indicating the operating status of the i-th thermal power unit; x i,v Indicates the power generation status of the thermal power unit at the initial moment; Represents the maximum power generation of the i-th thermal power unit. represents the ramp power of the i-th thermal power unit, T D and T U Respectively represent the maximum and minimum start and stop times.

[0145] Furthermore, the green electricity medium- and long-term contract constraints are expressed as follows:

[0146]

[0147] In the formula, is the green power contract decomposition amount of the jth green power unit in period t, represents the power generation of the jth green power unit in period t, It represents the maximum power generation of the jth green power unit in period t.

[0148] The scheduling results of the inter-regional optimization scheduling model considering green electricity trading are input into the carbon flow tracking model to calculate the indirect carbon emissions of each node.

[0149] Furthermore, the carbon potential matrix E is established N The calculation formula is expressed as:

[0150]

[0151] Where N is the total number of nodes and Q is the number of power generation nodes. Node active flux matrix P N is an N-dimensional diagonal matrix; the branch power distribution matrix P B(N×N) is a sparse matrix with N rows and N columns; P G The transposed matrix of the unit injection distribution matrix P G Element P Gi is the power injected by the generator set at the i-th node, and the generator set injection distribution matrix dimension is Q×N; the generator set carbon emission intensity vector E G Medium E Ji is the carbon emission intensity of the generator set at the i-th node, and the dimension of the carbon emission intensity vector of the generator set is Q×1;.

[0152] Furthermore, define the load carbon flow rate vector R L , the dimension is M×1, expressed as:

[0153] R L =P L ×E N

[0154] Where M is the number of load nodes, and the load distribution matrix P L (dimension is M×N), if the jth node is the mth (m=1,2,…,M)th node with load, and the active load is P, then the load P of the jth node L(m,j) =P, otherwise the load of the jth node is P L(m,j) =0.

[0155] Furthermore, the carbon emission vector E is defined as L, the dimension is M×1, expressed as:

[0156] E L =R L ×t

[0157] Furthermore, the carbon emission reduction factor C is defined as G , expressed as:

[0158]

[0159] In the formula, C Gj is the carbon emission reduction factor of the jth load node, E Lj is the carbon emission of the jth load node before using green electricity, E L ' j Carbon emissions after using green electricity for the jth load node.

[0160] Furthermore, the calculation methods of emission reduction factors for green power companies and power users are different due to the different transaction forms of green power trading objects. When calculating the carbon emission reduction factor for a single green power company and a single green power user, the formula is:

[0161]

[0162] In the formula, C g_grei is the emission reduction factor of the i-th green power enterprise conducting the green power transaction, C g-loadj is the emission reduction factor of the jth green electricity user who conducts the green electricity transaction.

[0163] Furthermore, when calculating the carbon emission reduction factor when multiple green power companies trade with a single green power user, the formula is:

[0164]

[0165]

[0166] In the formula, Q ij is the green electricity transaction volume between the i-th green electricity enterprise and the j-th green electricity user (node ​​or regional power grid); n is the total number of green electricity enterprises participating in the green electricity transaction; Q kj is the green electricity transaction volume between the kth green electricity enterprise and the jth green electricity user; C g_grek is the emission reduction factor of the kth green power enterprise;

[0167] Furthermore, when calculating the carbon emission reduction factor when a single green power enterprise conducts transactions with multiple green power users, the formula is expressed as:

[0168]

[0169]

[0170] Where m is the number of green electricity users that conduct green electricity transactions with the i-th green electricity enterprise, and n is the total number of green electricity enterprises that conduct green electricity transactions with the j-th green electricity user.

[0171] Example 2

[0172] The present invention provides a carbon emission reduction factor calculation system taking into account the constraints of green electricity medium- and long-term contracts. The system includes a memory, a processor, and a computer program stored in the memory. When the computer program is executed by the processor, it implements the various steps of the carbon emission reduction factor calculation method taking into account the constraints of green electricity medium- and long-term contracts as described in any of the above-mentioned implementation methods.

[0173] Example 3

[0174] The present invention provides a computer-readable storage medium, which stores a computer program. When the computer program is executed by a processor, it implements the various steps of the method for calculating the carbon emission reduction factor considering the constraints of green electricity medium- and long-term contracts as described in any of the above-mentioned implementation methods.

[0175] The present invention is not limited to what is described in the specification and implementation modes, and therefore additional advantages and modifications can be easily realized by those skilled in the art. Therefore, without departing from the spirit and scope of the general concept defined by the claims and their equivalents, the present invention is not limited to the specific details, representative devices, and illustrative examples shown and described herein.

Claims

1. The calculation method of carbon emission reduction factor considering the constraints of green electricity medium- and long-term contracts is characterized by: The following steps are involved: The calculation method of carbon emission reduction factor considering the constraints of green electricity medium- and long-term contracts includes the following steps: Reasonably decompose the total amount of green electricity medium- and long-term contracts into different time periods; Construct an inter-regional optimal dispatch model considering green electricity trading, including the objective function of minimizing the total system cost and several constraints; The several constraints mentioned include regional balance constraints, cross-regional interconnection line constraints, thermal power unit constraints, wind power unit constraints and green power medium- and long-term contract constraints; The cross-regional tie line constraints include DC tie line transmission power constraints, DC tie line transmission power ramp constraints, DC tie line network loss constraints, AC tie line transmission power, AC tie line transmission power constraints, and AC tie line network loss constraints; According to the dispatch results of the inter-regional optimal dispatch model considering green electricity trading, the carbon emission reduction factor is calculated through carbon flow tracking.

2. The method for calculating carbon emission reduction factors considering the constraints of green electricity medium- and long-term contracts according to claim 1 is characterized in that: The steps to reasonably decompose the total amount of green power medium- and long-term contracts into different time periods are as follows: The daily output curve left for the units participating in the market bidding is expressed as follows: In the formula, The load forecast curve for each day of the next year is predicted by the trading center at the beginning of the year, P MT (t) is the daily output curve reserved for the units participating in the market bidding, P NMT (t) is the output curve of the units not participating in the market, and t is time; The proportion of the contracted power of each green generator group to the total power generation of the generator groups participating in the market bidding is expressed as follows: In the formula, k j Q is the proportion of the contracted power of the jth green generator group to the total power generation of the generator groups participating in the market bidding, p is the total annual electricity consumption, represents the total power generation participating in the market bidding, is the total amount of contracts signed for the jth green power unit; The decomposition volume of green power medium- and long-term contracts in each period of the trading day is expressed by the formula as follows: In the formula, is the green electricity contract decomposition amount of the j-th green power unit in period t.

3. The method for calculating carbon emission reduction factors considering the constraints of green electricity medium- and long-term contracts according to claim 2 is characterized in that: The inter-regional optimization scheduling model considering green power trading is designed to complete the renewable energy consumption responsibility weight index, and the total power generation cost of the generator set and the inter-regional transmission cost of the regional power grid are minimized as the optimization objectives, and the objective function of minimizing the total system cost is constructed; the total system cost includes the power generation cost C gen , Carbon trading costs C car , the transmission cost of inter-regional interconnection lines C tra , network loss cost C was and the cost of purchasing excess consumption C tgc : Where T represents the total number of time periods considered; R represents the total number of regional power grids; N r represents the total number of units in the regional power grid r; K represents the total number of sections; represents the electricity cost of the i-th generator set; represents the carbon trading cost of the i-th generator; is the startup cost of thermal power unit i in period t; It indicates the power of the i-th thermal power unit in the k-th segment of time period t; α i,k,t N represents the declared price of the kth electricity energy of the i-th thermal power unit in time period t; Er and N GEr They represent the total number of thermal power units and new energy units that provide power supply to the regional power grid r; represents the power of the i-th green generator set in the k-th segment of time period t; γ i,k,t represents the price quoted by the i-th green power unit in the k-th period of time t; is the carbon emission intensity of the i-th thermal power unit, indicating the carbon emission corresponding to unit power generation, represents the benchmark carbon emission intensity corresponding to the i-th thermal power unit; β c is the carbon price; L represents the total number of inter-regional contact lines; represents the transmission price of the lth inter-regional tie line; and They represent the traditional energy and new energy power transmitted by the lth cross-regional interconnection line in time period t; C L,l represents the network loss penalty factor or network loss rate of the lth inter-regional tie line; and Respectively represent the network loss of AC tie line and DC tie line; inter-regional tie line includes inter-regional DC tie line and inter-regional AC tie line, N dc is the set of inter-regional DC interconnection lines; N ac It is a collection of inter-regional communication lines; is the excess consumption of the regional power grid or the market price of green certificates; It is the excess consumption amount or the electricity amount corresponding to the green certificate purchased by the regional power grid r during the assessment period T.

4. The method for calculating carbon emission reduction factors considering the constraints of green electricity medium- and long-term contracts according to claim 3 is characterized in that: The partition balance constraint is expressed as follows: In the formula, and They represent the total winning bid output of the i-th thermal power unit and the i-th new energy unit in the regional power grid r in period t, including the contract decomposed power; and They represent the injected traditional energy and new energy power of the lth tie line in the regional power grid r in period t, respectively. Positive numbers represent the power flowing into the regional power grid r. D j,r,t N represents the load forecast value of load j in regional power grid r during period t; Er and N GEr They represent thermal power units and new energy units that provide power to the regional power grid r, including point-to-grid power generating units that are not located in the regional power grid r; N Tr N represents the set of tie lines associated with the regional power grid r; Dr represents the total number of loads in the regional power grid r; T l,t represents the transmission power of the lth tie line. i,t represents the start and stop status of the i-th thermal power unit in the regional power grid r during period t; represents the maximum technical output of the i-th thermal power unit in time period t; represents the corresponding positive reserve capacity demand to the regional power grid r. represents the minimum technical output of the i-th thermal power unit in time period t; Represents the negative reserve capacity demand corresponding to the regional power grid r.

5. The method for calculating carbon emission reduction factors considering the constraints of green electricity medium- and long-term contracts according to claim 4 is characterized in that: The partitioned renewable energy consumption responsibility constraint is expressed as follows: Where μ is the non-hydro renewable energy consumption responsibility weight of a certain region. tgc,max Indicates the tradable excess consumption or upper limit of green certificates; It represents the output of the i-th renewable energy unit in the regional power grid r in the k-th segment of time period t.

6. The method for calculating carbon emission reduction factors considering the constraints of green electricity medium- and long-term contracts according to claim 5 is characterized in that: The cross-regional DC tie line constraint is expressed as follows: In the formula, and They represent the maximum and minimum transmission power of the lth DC tie line in time period t, Represents the transmission power of the lth DC tie line in time period t. and 0-1 variables representing up and down power, respectively; It represents the minimum climbing transmission power of the transmission line. Indicates the maximum climbing transmission power of the transmission line; It represents the linear proportionality coefficient of the network loss of the lth DC tie line; The cross-regional communication line constraint is expressed as follows: In the formula represents the power transfer distribution factor of the i-th generator set in the regional grid r to the l-th AC tie line, represents the power transfer distribution factor of the regional grid j load to the lth AC tie line, represents the power transfer distribution factor of the DC tie line to the AC tie line of the regional power grid, G j-a It represents the power transfer distribution factor of load j in regional power grid r to the AC tie line. and They represent the maximum and minimum transmission power of the lth AC tie line in period t respectively; represents the transmission power of the lth AC tie line in period t, P i,r,t represents the power generation of the i-th generator set in the regional power grid r in time period t; It represents the linear proportionality coefficient of the network loss of the lth DC tie line; The thermal power unit constraint is expressed as follows: Where P i,t represents the power generation of the i-th thermal power unit in time period t; P i,min represents the minimum output of the ith thermal power unit, P i,k,t It represents the output of the kth segment of the output curve of the i-th thermal power unit in the t-th period. i,t is a 0-1 variable that adjusts the power of the i-th thermal power unit in the t-th period, indicating the operating status of the i-th thermal power unit; x i,v Indicates the power generation status of the thermal power unit at the initial moment; Represents the maximum power generation of the i-th thermal power unit. represents the ramp power of the i-th thermal power unit, T D and T U Respectively represent the maximum and minimum start and stop times.

7. The method for calculating carbon emission reduction factors considering the constraints of green electricity medium- and long-term contracts according to claim 6 is characterized in that: The green electricity medium- and long-term contract constraints are expressed as follows: In the formula, is the green power contract decomposition amount of the jth green power unit in period t, represents the power generation of the jth green power unit in period t, It represents the maximum power generation of the jth green power unit in period t.

8. The method for calculating carbon emission reduction factors considering the constraints of green electricity medium- and long-term contracts according to claim 1 is characterized in that: The dispatch results of the inter-regional optimal dispatch model considering green electricity trading are input into the carbon flow tracking model to calculate the indirect carbon emissions of each node; Establish the carbon potential matrix E N The calculation formula is expressed as: Where N is the total number of nodes and Q is the number of power generation nodes. Node active flux matrix P N is an N-dimensional diagonal matrix; Branch power flow distribution matrix P B(N×N) is a sparse matrix with N rows and N columns; P G The transposed matrix of the unit injection distribution matrix P G Element P Gi is the power injected by the generator set at the i-th node, and the dimension of the generator set injection distribution matrix is ​​Q×N; Generator carbon emission intensity vector E G Medium E Ji is the carbon emission intensity of the generator set at the i-th node, and the dimension of the carbon emission intensity vector of the generator set is Q×1; Define the load carbon flow rate vector R L , the dimension is M×1, expressed as: R L =P L ×E N Where M is the number of load nodes, and the load distribution matrix P L If the jth node is the mth (m=1,2,…,M)th node with load and the active load is P, then the load P of the jth node is L(m,j) =P, otherwise the load of the jth node is P L(m,j) =0; Define the carbon emission vector E L , the dimension is M×1, expressed as: E L =R L ×t Define carbon emissions and calculate carbon reduction factor C G , expressed as: In the formula, C Gj is the carbon emission reduction factor of the jth load node, E Lj is the carbon emission of the jth load node before using green electricity, E L ' j The carbon emissions after using green electricity for the jth load node; When calculating the carbon emission reduction factor for a transaction between a single green power enterprise and a single green power user, the formula is: In the formula, C g_grei is the emission reduction factor of the i-th green power enterprise conducting the green power transaction, C g-loadj is the emission reduction factor of the jth green electricity user who conducts the green electricity transaction; When calculating the carbon emission reduction factor when multiple green power companies trade with a single green power user, the formula is: In the formula, Q ij is the green electricity transaction volume between the i-th green electricity enterprise and the j-th green electricity user, Q kj is the green electricity transaction volume between the kth green electricity enterprise and the jth green electricity user; n is the total number of green electricity enterprises participating in the green electricity transaction; C g_grek is the emission reduction factor of the kth green power enterprise; When calculating the carbon emission reduction factor for a single green power enterprise trading with multiple green power users, the formula is: Where m is the number of green electricity users who conduct green electricity transactions with the i-th green electricity enterprise.

9. A carbon emission reduction factor calculation system considering green electricity medium- and long-term contract constraints, the system comprising a memory, a processor, and a computer program stored in the memory, characterized in that: When the computer program is executed by the processor, each step of the method for calculating the carbon emission reduction factor taking into account the constraints of green electricity medium- and long-term contracts is implemented as described in any one of claims 1 to 8.

10. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, each step of the method for calculating the carbon emission reduction factor taking into account the constraints of green electricity medium- and long-term contracts is implemented as claimed in any one of claims 1 to 8.

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