Method, device and storage medium for determining spare deduction amount considering multi-section coupling

Abstract

The present invention provides a method, device and storage medium for determining spare reduction amounts considering multi-section coupling, quantifies the degree of alleviation of the unit's overloaded power flow set in the system as an evaluation index, and updates and iterates the spare reduction amounts of each unit based on this index, and finally realizes the identification of effective spare reduction amounts for the entire network. The present invention comprehensively considers the influence of the generating unit on the over-limit section, solves the problem that the spare provided by the generating unit cannot be called due to section constraints, and improves the safety and stability of the power system.

Description

Technical Field

[0001] The present invention belongs to the technical field of effective power grid reserve, and particularly relates to a method for calculating reserve deduction considering multi-section coupling, a method for determining reserve deduction amount of related devices, a device, and a storage medium. Background Art

[0002] On the premise of ensuring system power balance, in order to prevent system load prediction deviation and system supply-demand imbalance fluctuations caused by various actual operation accidents, the general system needs to reserve a certain amount of capacity. In actual operation, there is a part of the reserve provided by some generating units that cannot be called due to section constraints. The existing reserve calculation methods ignore the influence of section constraints on reserve availability, resulting in inaccurate system reserve calculation and a decline in the system's ability to resist risks. Therefore, quantifying this part of ineffective reserve is of great significance for the stable operation of the power grid. Summary of the Invention

[0003] The present invention provides a method and device for determining reserve deduction amount considering multi-section coupling, which are used to solve the problem that the existing reserve calculation methods ignore the influence of section constraints on reserve availability.

[0004] To achieve the above technical objectives, the present invention adopts the following technical solutions.

[0005] On the one hand, the present invention provides a method for determining reserve deduction amount considering multi-section coupling, including:

[0006] Obtain unit operation parameters, system parameters, and network parameters;

[0007] Based on the unit operation parameters, determine the initial unit plan, the upper limit of unit output, and the unit power regulation power; based on the initial unit plan, the upper limit of unit output, and the unit power regulation power, determine the maximum reserve capacity of each unit without considering section power flow limits;

[0008] Determine the set of heavy-load sections considering reserve deduction, the set of overloaded sections considering reserve deduction, and the set of units considering reserve deduction;

[0009] According to the system parameters and network parameters, calculate the evaluation index of the degree of relief of section overload power flow of each unit in the set of units considering reserve deduction for the overloaded section set;

[0010] Execute the following steps in a loop: Sort all units according to the obtained evaluation indicators; starting from the unit with the highest evaluation indicator, sequentially reduce the reserve capacity of each unit from the maximum reserve capacity until a certain section s in the overloaded section set is no longer overloaded. At this time, the reduction in the unit reserve capacity is the reserve reduction amount of this unit, and at the same time, remove section s from the overloaded section set; if the unit reserve capacity of a unit is reduced to zero and there is no section in the overloaded section set that is not overloaded, then the maximum reserve capacity of this unit at this time is the reserve reduction amount of this unit; after traversing all units in the unit set considering reserve reduction, if the overloaded section set is not empty, recalculate the evaluation indicators of each unit in the unit set considering reserve reduction for the degree of alleviating the overloaded power flow of the sections in the overloaded section set, and loop through this step until the overloaded section set is empty;

[0011] If the overloaded section set is empty, the sum of the reserve reduction amounts of all units is the system reserve reduction amount.

[0012] Furthermore, the maximum reserve capacity of the unit is expressed as:

[0013]

[0014] In the formula, represents the maximum reserve capacity of unit i at time t, is the upper limit of the output of unit i at time t, represents the initial plan of unit i at time t, Δp i represents the unit power regulation rate.

[0015] Furthermore, determine the overloaded section set C t considering reserve reduction, and its expression is as follows:

[0016]

[0017] C t ={s|P s,t ′≥0.9P s max}

[0018] where P s,t ′ represents the power flow of section s at time t considering the maximum reserve capacity of the unit; represents the initial power flow of section s at time t, P s max is the section power flow limit value, G i-s is the sensitivity factor of unit i to section s, S is the section set, N is the total number of units, represents the maximum reserve capacity of unit i at time t.

[0019] Furthermore, determine the overload section set D considering reserve deductions t The specific method is as follows:

[0020] Statistically consider the section set C with reserve deductions t The over-limit value ΔP of the power flow of each section in s,t , and the section where the over-limit value of the power flow is greater than zero is the overloaded power flow section;

[0021] Add the overloaded power flow section to the overload section set D considering reserve deductions t , which is expressed as:

[0022] ΔP s,t = max(0, P s,t ′ - P s max ), s ∈ C t

[0023] D t = {s|ΔP s,t > 0}

[0024] where P s,t ′ represents the power flow of section s at time t considering the maximum reserve capacity of the unit; P s max is the power flow limit of the section, and C t is the heavy-load section set considering reserve deductions.

[0025] Furthermore, determine the unit set Z considering reserve deductions t The specific method is as follows:

[0026] The maximum reserve capacity of the unit i at time t that is in the operating state is greater than zero, and the sensitivity factor G of the unit to section s i-s is greater than or equal to the sensitivity threshold, and the unit is added to the unit set Z considering reserve deductions t , where section s belongs to the heavy-load section set and the overload section set, which is expressed as:

[0027]

[0028] where ε is the sensitivity threshold, is the maximum reserve capacity of unit i at time t, C t is the heavy-load section set considering reserve deductions, and D t is the overload section set considering reserve deductions.

[0029] Furthermore, the evaluation index is expressed as:

[0030]

[0031] where D t is the set of overloaded sections considering spare deductions, and G i-s is the sensitivity factor of unit i to section s, and Z t is the set of units considering spare deductions.

[0032] In a second aspect, the present invention provides a device for determining spare deductions considering multi-section coupling, including a parameter acquisition module, a maximum spare capacity determination module for units, a section set determination module, an evaluation index determination and sorting module, and a system spare deduction amount determination module;

[0033] The parameter acquisition module is used to acquire unit operation parameters, system parameters, and network parameters;

[0034] The maximum spare capacity determination module for units is used to determine the initial plan of the unit, the upper limit of the unit output, and the power regulation power of the unit based on the unit operation parameters; based on the initial plan of the unit, the upper limit of the unit output, and the power regulation power of the unit, determine the maximum spare capacity of each unit without considering the section power flow limit;

[0035] The section set determination module is used to determine the set of heavy-load sections considering spare deductions, the set of overloaded sections considering spare deductions, and the set of units considering spare deductions;

[0036] The evaluation index determination and sorting module is used to calculate the evaluation index of the degree of relief of the section overload power flow in the set of overloaded sections by each unit in the set of units considering spare deductions according to the system parameters and network parameters;

[0037] The system spare deduction amount determination module is used to repeatedly execute the following steps: sort all units according to the obtained evaluation indexes; starting from the unit with the highest evaluation index, sequentially reduce the spare capacity of each unit from the maximum spare capacity until a certain section s in the set of heavy-load sections is not overloaded. At this time, the reduction amount of the unit spare capacity is the spare deduction amount of the unit, and at the same time, remove section s from the set of heavy-load sections; if the unit spare capacity of the unit is reduced to zero and there is no section in the set of heavy-load sections that is not overloaded, then the maximum spare capacity of the unit at this time is the spare deduction amount of the unit; traverse all units in the set of units considering spare deductions. If the set of heavy-load sections is not empty, recalculate the evaluation index of the degree of relief of the section overload power flow in the set of overloaded sections by each unit in the set of units considering spare deductions, and repeatedly execute this step until the set of heavy-load sections is empty; if the set of heavy-load sections is empty, the sum of the spare deduction amounts of all units is the system spare deduction amount.

[0038] Furthermore, the maximum spare capacity determination module for units determines that the maximum spare capacity of the unit is expressed as:

[0039]

[0040] In the formula, represents the maximum reserve capacity of unit i at time t, is the output upper limit of unit i at time t, represents the initial plan of unit i at time t, Δp i represents the unit power regulation rate.

[0041] Furthermore, the evaluation indexes determined by the evaluation index determination and sorting module are expressed as follows:

[0042] where D t is the set of overloaded sections considering reserve deduction, G i-s is the sensitivity factor of unit i to section s, Z t is the set of units considering reserve deduction.

[0043] The present invention also provides a computer-readable storage medium, which stores a computer program. When the computer program is executed by a processor, the steps of the method provided by any possible implementation manner of the first aspect are realized.

[0044] The beneficial technical effects achieved by the present invention:

[0045] The present invention quantifies the degree of alleviation of the overloaded power flow of the sections in the system overloaded power flow section set by the unit as an evaluation index, sorts according to the evaluation index, and successively reduces the unit reserve by the unit according to the sorting to determine the change amount of the system power flow limit value. The present invention considers the influence of the generating unit on the overstepped section, solves the problem that the reserve provided by some generating units in actual operation cannot be called due to being restricted by the section constraint, and considers the influence of the section constraint on the availability of the reserve; based on the index update iteration, the reserve deduction amount of each unit is reduced, and finally the effective reserve identification of the whole network is realized. The reserve deduction amount determined by the present invention is more accurate and has important significance for the stable operation of the power grid. Specific embodiments

[0046] For the convenience of those of ordinary skill in the art to understand and implement the present invention, the present invention will be further described in detail below in conjunction with embodiments. It should be understood that the embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0047] Embodiment: A method for determining the reserve deduction amount considering multi-section coupling includes:

[0048] Step 1: Obtain key parameters, including key data such as unit operation parameters, system operation parameters, and network parameters.

[0049] The operating parameters of the unit include: the initial unit plan, the initial unit state, the upper and lower limits of the unit output, and the unit power regulation rate; the operating parameters of the system include: the system reserve demand; the network parameters include: the initial section power flow, the section power flow limit, and the power transfer factor of the unit injection power to the section;

[0050] Step 2: Based on the initial unit plan, the upper limit of the unit output, and the unit power regulation rate, calculate the maximum reserve capacity of each unit without considering the section power flow limit. Among them, the maximum reserve capacity of the unit should be less than the upper limit of the unit output minus the initial unit plan, and the maximum reserve capacity of the unit is less than the unit power regulation rate, which is characterized as:

[0051]

[0052] In the formula, represents the maximum reserve capacity of unit i at time t, represents the upper limit of the output of unit i at time t, represents the initial plan of unit i at time t, Δp i represents the unit power regulation rate. Step 3: Determine the set C of heavy-load sections considering reserve deduction t , determine the set D of overloaded sections considering reserve deduction t , and determine the set Z of units considering reserve deduction t .

[0053] Determine the set C of heavy-load sections considering reserve deduction t The specific method is as follows: First, calculate the power flow of each section considering the maximum reserve capacity of the unit, and then add the heavy-load sections whose power flow load (i.e., the section power flow) is greater than or equal to the threshold (the threshold is the section power flow limit, default 90%, can be customized) to the set C of heavy-load sections considering reserve deduction t ,

[0054] It is expressed as:

[0055] C t ={s|P s,t ′≥0.9P s max}

[0056] where P s,t ′ represents the section power flow considering the maximum reserve capacity of the unit, that is, the power flow of section s at time t considering the maximum reserve capacity of the unit; represents the initial section power flow of section s at time t, P s max is the section power flow limit, G i-s is the sensitivity factor of unit i to section s, S is the set of sections, and N is the total number of units. Denote the maximum reserve capacity of unit \(i\) at time \(t\).

[0057] Determine the set \(D\) of overloaded sections considering reserve deduction t The specific method is as follows: Statistically analyze the set \(C\) of sections considering reserve deduction t The over-limit value \(\Delta P\) of the power flow of each section in s,t If the over-limit value of the power flow is greater than zero, the section is an overloaded power flow section;

[0058] Add the overloaded power flow section to the set \(D\) of overloaded sections considering reserve deduction t ,

[0059] \(\Delta P\) s,t =\(\max(0, P\) s,t '-P s max ), s\in C t

[0060] D t =\(\{s|\Delta P\) s,t >0\}\)

[0061] Determine the set \(Z\) of units considering reserve deduction t The specific method is as follows: Add units that are in the operating state, have a maximum reserve capacity greater than zero, and the sensitivity factor of the unit with respect to a certain section \(s\) in the set \(C\) of heavily loaded sections t or the set \(D\) of overloaded sections t is greater than or equal to the sensitivity threshold (in the embodiment, the sensitivity threshold is defaulted to 0.05 and can be customized) to the set \(Z\) of units considering reserve deduction t , expressed as:

[0062]

[0063] In the formula, Denote the maximum reserve capacity of unit \(i\) at time \(t\), and \(G\) i-s is the sensitivity factor of unit \(i\) to section \(s\).

[0064] Step 4: Calculate the quantitative evaluation index of the degree of overloaded power flow mitigation of the unit, use the evaluation index for sorting, and sequentially reduce the unit reserve according to the sorting to determine the change amount of the over-limit value of the system power flow.

[0065] In this embodiment, the sum of the sensitivity factors of unit \(i\) in the set \(Z\) of units considering reserve deduction t to all sections \(s\) in the set \(D\) of overloaded sections t is used as the evaluation index \(r\) of unit \(i\) according to the degree of overloaded power flow mitigation, i , expressed as follows:

[0066]

[0067] Step 5: According to the evaluation index r i Sort all the units in the unit set considering the standby deduction in descending order. According to the sorting, sequentially reduce the standby of unit i starting from the maximum standby capacity until a certain section s in the overloaded section set C t is not overloaded. At this time, the reduction amount of the unit standby capacity is the standby deduction amount of this unit, and at the same time update the overloaded section set by removing section s from the overloaded section set C t If the standby of unit i is reduced to 0 and there is no section in the overloaded section set C t that is not overloaded, then i++, and at this time the maximum standby capacity of the unit is the standby deduction amount of this unit.

[0068] Step 6: Determine whether the overloaded section set C t is empty. If the overloaded section set C t is an empty set, then calculate the sum of the standby deduction amounts of all units as the system standby deduction amount, and end the process; otherwise, if the overloaded section set C t is not empty, then go to Step 4.

[0069] The present invention provides a method for determining the standby deduction amount considering multi-section coupling, which quantifies the degree of alleviation of the unit on the system overload power flow set as an evaluation index, and updates and iterates the deducted standby amount of each unit based on this index, and finally realizes the identification of the effective standby of the whole network. The present invention comprehensively considers the influence of the generating unit on the over-limit section, solves the problem that the standby provided by the generating unit cannot be called due to the section constraint, and improves the safety and stability of the power system.

[0070] Corresponding to the above embodiments, the embodiment of the present invention further provides a device for determining the standby deduction amount considering multi-section coupling, including a parameter acquisition module, a unit maximum standby capacity determination module, a section set determination module, an evaluation index determination and sorting module, and a system standby deduction amount determination module;

[0071] The parameter acquisition module is used to acquire unit operation parameters, system parameters, and network parameters;

[0072] The unit maximum standby capacity determination module is used to determine the initial plan of the unit, the upper limit of the unit output, and the power regulation power of the unit based on the unit operation parameters; based on the initial plan of the unit, the upper limit of the unit output, and the power regulation power of the unit, determine the maximum standby capacity of each unit without considering the section power flow limit;

[0073] The section set determination module is used to determine the overloaded section set considering standby deduction, the overloaded section set considering standby deduction, and the unit set considering standby deduction;

[0074] The evaluation index determination and sorting module is used to calculate the evaluation indexes of the degree of relief of the sectional overload power flow in the overload sectional set by each unit in the unit set considering spare reduction according to the system parameters and network parameters;

[0075] The system spare reduction amount determination module is used to loop through the following steps: sort all units according to the obtained evaluation indexes; starting from the unit with the highest evaluation index, sequentially reduce the spare capacity of each unit from the maximum spare capacity until a certain section s in the overloaded section set is no longer overloaded. At this time, the reduction amount of the unit's spare capacity is the spare reduction amount of this unit, and at the same time, remove section s from the overloaded section set; if the unit's spare capacity is reduced to zero and there is no section in the overloaded section set that is not overloaded, then the maximum spare capacity of this unit at this time is the spare reduction amount of this unit; after traversing all units in the unit set considering spare reduction, if the overloaded section set is not empty, recalculate the evaluation indexes of the degree of relief of the sectional overload power flow in the overload sectional set by each unit in the unit set considering spare reduction, and loop through this step until the overloaded section set is empty; if the overloaded section set is empty, the sum of the spare reduction amounts of all units is the system spare reduction amount.

[0076] The unit maximum spare capacity determination module determines that the unit maximum spare capacity is expressed as:

[0077]

[0078] In the formula, represents the maximum spare capacity of unit i at time t, is the upper limit of the output of unit i at time t, represents the initial plan of unit i at time t, Δp i represents the unit power regulation rate.

[0079] The evaluation indexes determined by the evaluation index determination and sorting module are expressed as follows:

[0080]

[0081] Where D t is the overload sectional set considering spare reduction, G i-s is the sensitivity factor of unit i to section s, Z t is the unit set considering spare reduction.

[0082] Those skilled in the art can clearly understand that for the convenience and simplicity of description, the specific working processes of the above-described systems, devices / modules can refer to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0083] Those skilled in the art should understand that the embodiments of the present application can be provided as a method, a system, or a computer program product. Therefore, the present application can take the form of an all-hardware embodiment, an all-software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present application can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that contain computer-usable program code.

[0084] The embodiments of the present invention have been described above, but the present invention is not limited to the above specific embodiments. The above specific embodiments are merely illustrative and not restrictive. Under the inspiration of the present invention, those of ordinary skill in the art can also make many forms without departing from the spirit of the present invention and the scope protected by the claims. All of these are within the protection scope of the present invention.

Claims

1. Method for determining spare reduction amount considering multi-section coupling, Characterized in that, Comprising: Obtaining unit operation parameters, system parameters and network parameters; wherein, the unit operation parameters include: initial unit plan, initial unit state, upper and lower limits of unit output, and unit power regulation rate; the system operation parameters include: system spare demand; the network parameters include: initial section power flow, section power flow limit, and power transfer factor of unit injection power to the section; Determining the initial unit plan, upper limit of unit output and unit power regulation power based on the unit operation parameters; determining the maximum spare capacity of each unit without considering the section power flow limit based on the initial unit plan, upper limit of unit output and unit power regulation power; Determining the set of heavy-load sections considering spare reduction, the set of overloaded sections considering spare reduction, and the set of units considering spare reduction; Among them, the set C of overload cross-sections considering alternative deductions is determined t The expression is as follows: C t = {s | P s,t ′ ≥ 0.9P s max} Among which P s,t ′ represents the power flow of section s at time t considering the maximum reserve capacity of the unit; represents the initial power flow of section s at time t, P s max is the power flow limit of the section, G i-s is the sensitivity factor of unit i to section s, S is the set of sections, N is the total number of units, represents the maximum reserve capacity of unit i at time t; Among them, the specific method for determining the overload cross-section set D considering the spare deduction is as follows: t is as follows: Cross-section set C considering statistical spare deductions t The over-limit value ΔP of the power flow of each cross-section s,t , and the cross-section where the over-limit value of the power flow is greater than zero is the overloaded power flow cross-section; Add the overload power flow section to the overload section set D considering reserve deduction t , expressed as: ΔP s,t = max(0, P s,t ′ - P s max ), s ∈ C t D t = {s | ΔP s,t > 0} Among which P s,t ′ represents the power flow of section s at time t considering the maximum reserve capacity of the unit; P s max is the power flow limit of the section, and C t is the set of heavily loaded sections considering reserve deduction; Among them, the specific method for determining the unit set Z considering the spare deduction is as follows: t is as follows: The maximum reserve capacity of unit i at time t when it is in the operating state is greater than zero, and the sensitivity factor G of the unit to section s i-s is greater than or equal to the sensitivity threshold, and the unit is added to the set Z of units considered for reserve deduction t , where section s belongs to the set of heavily loaded sections and the set of overloaded sections, and is expressed as: where ε is the sensitivity threshold, is the maximum reserve capacity of unit i at time t, C t is the set of heavy load sections considering reserve deduction, D t is the set of overloaded sections considering reserve deduction; Calculating, according to the system parameters and network parameters, an evaluation index of the degree of relief of the section overload power flow in the set of overloaded sections by each unit in the set of units considering spare reduction; Wherein, the evaluation index is expressed as: Among which D t is the set of overload sections considering spare deductions, G i-s is the sensitivity factor of unit i to section s, Z t is the set of units considering spare deductions; Repeatedly execute the following steps: Sort all units according to the obtained evaluation indexes; starting from the unit with the highest evaluation index, sequentially reduce the spare capacity of each unit from the maximum spare capacity until a certain section s in the set of heavy-load sections is no longer overloaded. At this time, the reduction amount of the unit spare capacity is the spare reduction amount of the unit, and at the same time, remove section s from the set of heavy-load sections; if the unit spare capacity of the unit is reduced to zero and there is no section in the set of heavy-load sections that is not overloaded, then the maximum spare capacity of the unit at this time is the spare reduction amount of the unit; traverse all units in the set of units considering spare reduction. If the set of heavy-load sections is not empty, recalculate the evaluation index of the degree of relief of the section overload power flow in the set of overloaded sections by each unit in the set of units considering spare reduction, and repeatedly execute this step until the set of heavy-load sections is empty; if the set of heavy-load sections is empty, the sum of the spare reduction amounts of all units is the system spare reduction amount.

2. The method for determining spare reduction amount considering multi-section coupling according to claim 1, Characterized in that, The maximum spare capacity of the unit is expressed as: In the formula, represents the maximum reserve capacity of unit i at time t, is the output upper limit of unit i at time t, represents the initial plan of unit i at time t, Δp i represents the unit power regulation rate.

3. Device for determining spare reduction amount considering multi-section coupling based on the method for determining spare reduction amount considering multi-section coupling according to claim 1, Characterized in that, Comprising a parameter acquisition module, A module for determining the maximum spare capacity of the unit, a module for determining the section set, a module for determining and sorting the evaluation index, and a module for determining the system spare reduction amount; The parameter acquisition module is used to obtain unit operation parameters, system parameters and network parameters; The module for determining the maximum spare capacity of the unit is used to determine the initial unit plan, upper limit of unit output and unit power regulation power based on the unit operation parameters; and determine the maximum spare capacity of each unit without considering the section power flow limit based on the initial unit plan, upper limit of unit output and unit power regulation power; The section set determination module is used to determine the set of heavy-load sections considering spare reduction, the set of overloaded sections considering spare reduction, and the set of units considering spare reduction; The evaluation index determination and ranking module is used to calculate the evaluation index of the degree of relief of the sectional overload power flow in the overload sectional set for each unit in the unit set considering spare deduction according to the system parameters and network parameters; The system spare deduction amount determination module is used to repeatedly execute the following steps: sort all units according to the obtained evaluation indexes; starting from the unit with the highest evaluation index, sequentially reduce the spare capacity of each unit from the maximum spare capacity until a certain section s in the heavy-load sectional set is no longer overloaded. At this time, the reduction amount of the unit's spare capacity is the spare deduction amount of this unit, and at the same time, remove section s from the heavy-load sectional set; if the unit's spare capacity is reduced to zero and there is no section in the heavy-load sectional set that is not overloaded, then the maximum spare capacity of this unit is the spare deduction amount of this unit; traverse all units in the unit set considering spare deduction. If the heavy-load sectional set is not empty, recalculate the evaluation index of the degree of relief of the sectional overload power flow in the overload sectional set for each unit in the unit set considering spare deduction, and repeatedly execute this step until the heavy-load sectional set is empty; if the heavy-load sectional set is empty, the sum of the spare deduction amounts of all units is the system spare deduction amount.

4. The device for determining the spare deduction amount considering multi-section coupling according to claim 3, characterized in that the unit maximum spare capacity determination module determines that the unit maximum spare capacity is expressed as: In the formula, represents the maximum reserve capacity of unit i at time t, is the upper limit of the output of unit i at time t, represents the initial plan of unit i at time t, Δp i represents the unit power regulation rate.

5. A computer-readable storage medium, the computer-readable storage medium stores a computer program, characterized in that when the computer program is executed by a processor, it implements the steps of the method according to any one of claims 1 to 2.

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