Novel power system power balance principle and engineering mode application method

Abstract

The invention discloses a novel power system power balance principle and engineering mode application method. The method comprises the following steps: counting the probability density and probability distribution of balance elements in each balance area; each balance area independently carries out initial balance; setting a balance target; setting an initial balance boundary in each balance area based on a novel basic balance principle supply keeping stage, and constructing a novel basic balance equation; in a supply guaranteeing stage based on the novel integrated balance principle, a novel integrated balance equation is constructed, and a novel integrated balance equation resolving method based on numerical calculation is provided; a new energy consumption strategy of each independent balance area is formulated based on a novel basic balance principle consumption promoting stage; based on a novel integrated balance principle absorption promoting stage, judging whether to enter an integrated balance absorption promoting link or not; according to the method, the same-dimensional quantitative control of the balance risk and the conventional balance element is realized, the unified balance operation of'probabilization + integration + total element 'is realized, and the overall planning of'supply guarantee' and'consumption 'is realized.

Description

Technical Field

[0001] The present invention relates to the field of power systems, and particularly to a novel power system power balance principle and an engineering mode application method. Background Art

[0002] From the perspective of the development of power systems, the key to deeply promoting the energy revolution is to build a novel power system suitable for China's national conditions and with stronger new energy consumption capacity. The core connotation is to promote the low-carbon, safe and efficient development of power systems, and the essential task is to serve the national energy development of carbon peak and carbon neutrality. During the construction of the novel power system, it is crucial to innovate the power balance principle according to the characteristics of new energy power generation and the balance law of the novel power system.

[0003] In recent years, the research on the power balance principle of the novel power system has been gradually deepened. In terms of the macro direction, existing research has summarized some main characteristics of the power balance of the novel power system: (1) the interweaving and coupling of "probabilistic" and "integrated", (2) the coexistence of the problems of "power supply guarantee" and "new energy consumption", (3) the widespread existence of "balance risk" and "balance uncertainty", etc. At the same time, it is also generally mentioned that it is urgent to solve the basic theoretical problems of power and electricity balance in the construction of the novel power system. In terms of specific problem methods, existing research has carried out extensive research on the new problems and new phenomena emerging in recent power balance practices. Representative research directions include: the response to the randomness and uncertainty of power balance, the power and electricity balance mechanism and balance strategy, the overall optimization and utilization of regulation capabilities and balance resources, the design and improvement of market mechanisms adapted to the characteristics of the new balance, etc. Generally speaking, the research in the macro direction category has pointed out the direction for the research on the power balance principle of the novel power system, but no in-depth derivation research has been carried out on specific mathematical methods; the research in the specific problem method category focuses on solving a certain specific problem of the power balance of the novel power system, but fails to systematically propose a set of basic principles for the power balance of the novel power system.

[0004] The core characteristics of the power balance of the novel power system include: (1) the randomization of the balance mechanism (mathematical model based on probability operation); (2) the integration of the balance mode across the whole network (overall optimization and mutual assistance by coordinating resources across the whole network); (3) the complexity of the balance goal (coupling of power supply guarantee and consumption problems); (4) the diversification of balance elements (overall element balance); (5) the pervasiveness of balance risks (quantitative calculation and control of balance risks); (6) the "computing power" of balance analysis (balance analysis based on large-scale numerical calculations).

[0005] The current technical research mainly has the following deficiencies:

[0006] (1) The probabilistic methods for power balance in current independent balance areas are all random variable equations, which are complex and difficult to apply in engineering, and fail to achieve the same-dimensional analysis of balance risks and conventional balance elements.

[0007] (2) There is no probabilistic analysis and calculation method for the whole-network integrated balance (considering the mutual support among balance intervals) and its engineering practice plan.

[0008] In the prior art, there is a conventional basic balance equation. For an independent balance area, the basic balance equation of the conventional balance mode is as follows:

[0009]

[0010] In the above formula, δ and σ are the upper and lower balance margins respectively; R is the maximum power generation capacity of the conventional power source, which is mainly determined by the on-line capacity. α is the peak shaving coefficient of the conventional power source, reflecting the regulation ability of the conventional power source; T is the planned power of the tie line, which is generally formed by market means such as medium- and long-term transactions, spot, and ancillary services; n and l are the predicted new energy output and the predicted load size respectively, and ρ is the reserve rate reserved according to the power system safety and stability guidelines; x is the amount of load-side management measures (electricity), and y is the amount of abandoned new energy (electricity). The physical meaning of the above formula is to coordinate various balance elements to ensure that both the upper and lower balance margins are greater than zero.

[0011] It can be seen from the above formula that the conventional balance equation is a set of definite algebraic equations, and it has the following deficiencies in the environment of the new power system:

[0012] (1) It does not conduct quantitative analysis on the uncertainty of balance elements;

[0013] (2) According to engineering practice experience, the uncertainty of balance elements is suppressed by macroscopically reserving a certain amount of reserve (ρ);

[0014] (3) In the process of reserving reserve, the focus is on the uncertainty of the load (ρ is called the load reserve rate in relevant standards), and the high randomness and strong volatility of new energy are not fully considered. With the continuous increase of the new energy penetration rate in the environment of the new power system, the conventional balance equation has gradually become inadaptable to the balance needs of the new power system. Summary of the Invention

[0015] In view of this, this application focuses on systematically solving the problems of the whole-network multi-objective and integrated balance analysis and calculation means and methods in the environment of randomized balance elements of the new power system from the basic theory and engineering practice levels in the direction of adapting to the core characteristics of the new power system balance. The purpose of the present invention is to improve the deficiencies of the existing power system power balance principle and engineering mode, systematically focus on the random coupling and multi-element coordination problems faced by the power balance of the new power system from the basic theory level, and solve the key problems such as the intertwined coupling of "probabilistic" and "integrated" in power balance, the mutual influence of "power supply guarantee" and "consumption", and the difficulty in unified quantitative characterization of "balance risk" and "balance target" in the environment of the new power system.

[0016] To solve the above technical problems, the present invention provides a method for applying the power balance principle and engineering mode of a new power system, including the following steps:

[0017] S1. According to the random characteristic laws of the balance elements in each balance area, statistically calculate the probability density and probability distribution; each balance area independently conducts initial balance; considering the requirements for the probability distribution of the balance margin of each balance area and the whole network, set the balance target;

[0018] S2. Based on the power supply guarantee stage of the new basic balance principle, construct a new basic balance equation in algebraic configuration;

[0019] S3. Based on the power supply guarantee stage of the new integrated balance principle, randomly transform the conventional integrated balance equation to construct a new integrated balance equation, and propose a solution method for the new integrated balance equation based on numerical calculation;

[0020] S4. Based on the new energy consumption promotion stage of the new basic balance principle, formulate new energy consumption strategies for each independent balance area, and judge whether there is large-scale new energy abandonment. If so, jump to step S5; otherwise, end;

[0021] S5. Based on the new energy consumption promotion stage of the new integrated balance principle, judge whether to enter the integrated balance new energy consumption promotion link. If so, enter the new integrated balance new energy consumption promotion engineering mode K o , and then conduct subsequent judgments; otherwise, end.

[0022] Among them, based on the new integrated balance equation, considering the differences in the balance target, balance means, and balance process, summarize the new integrated balance engineering mode. The new integrated balance engineering mode includes the new integrated balance power supply guarantee engineering mode H o and the new integrated balance new energy consumption promotion engineering mode K o , the new integrated balance power supply guarantee engineering mode H o includes the natural mutual assistance mode and the collaborative mutual assistance mode The new integrated balance new energy consumption promotion engineering mode K o includes the natural mutual assistance mode and the collaborative mutual assistance mode

[0023] Furthermore, the specific steps of step S2 include the following steps:

[0024] S201. Each balance area independently sets the initial balance boundary, calculates the risk conversion factor of the independent balance area Construct a new basic balance equation in algebraic configuration;

[0025] S202. Determine whether the balance requirement is met. If so, jump to step S4; otherwise, jump to step S203.

[0026] S203. Determine whether the conventional means in the independent balance area have been exhausted. If so, jump to step S204; otherwise, adjust the balance boundary of the independent balance area, and then return to the new basic balance equation to form a closed loop.

[0027] S204. Determine whether to enable integrated balance for power supply. If so, jump to step S3; otherwise, increase the load management measure amount, and then return to the new basic balance equation to form a closed loop.

[0028] Further, step S3 further includes the following steps: Consider the probability distributions of the balance margins of each balance area and the whole network under the integrated balance environment, compare the calculation results of the new integrated balance equation solving method with the set balance target, determine whether the balance requirement is met. If so, jump to step S4; otherwise, adopt the natural mutual assistance mode o and the collaborative mutual assistance mode under the new integrated balance power supply project mode H to adjust the balance boundary of the relevant balance area, and then return to the new integrated balance equation to form a closed loop.

[0029] Further, the subsequent judgment in step S5 specifically includes the following steps: Determine whether the maximum promotion of consumption has been achieved. If so, adjust the new energy consumption strategies of each balance area; otherwise, adopt the natural mutual assistance mode o and the collaborative mutual assistance mode under the new integrated balance new energy consumption promotion project mode K to adjust the balance boundary of the relevant balance area, and then return to the new integrated balance new energy consumption promotion project mode K o to form a closed loop.

[0030] Further, the new basic balance equation is:

[0031]

[0032] In the formula: δ and σ are the upper and lower balance margins respectively; R is the maximum power generation capacity of conventional power sources; α is the peak shaving coefficient of conventional power sources; T is the planned power of tie lines; n and l are the predicted new energy output and the predicted load size respectively; ρ is the reserve rate reserved according to the power system safety and stability guidelines; x is the load side management measure amount; y is the new energy abandonment amount; δ Λ , λ Λ characterize the balance risk control requirements; n o is the new energy output random variable; Δn ois the deviation of the random variable; is the random variable Δn o probability density; represents the probability density and probability distribution function of Δn o ; is inverse function; Only the new energy balance factor is introduced as a random variable in this equation.

[0033] The new integrated balance equation is as follows:

[0034]

[0035] In the formula: Δn o is the new energy deviation; δ o is the balance margin before and after mutual assistance; Δs o is the mutual assistance power; Without considering the random characteristics of the balance margin σ, σ is controlled as an algebraic variable in the balance mode arrangement; reflects the balance risk; is the risk control sub-equation set of each balance area; is the whole network risk control equation; ΔX o is the whole network balance gap, and its physical meaning is that the probability that the whole network balance gap is less than ΔX Λ is greater than λ Λ ; Only the new energy balance factor is introduced as a random variable in this equation.

[0036] The solution method of the new integrated balance equation based on numerical calculation is simply called the S calculation process, including three links: decomposition, calculation, and induction.

[0037] Furthermore, after introducing the balance factor load, conventional power source, planned power of the tie line, and load management measures, the expression of the upper balance margin is converted to:

[0038] δ o = R + T + n - ρl + x + (Δn o + Δl o + ΔR o + ΔT o + Δx o )(29)

[0039] In the formula: Δl o , ΔR o , ΔT o , Δx o respectively represent the random deviations of the load, conventional power generation capacity, planned power of the tie line, and load management measures;

[0040] The integrated balance carried out based on Equation (29) is the all-factor integrated balance, which can be further divided into the case without considering the uncertainty of tie lines and the case considering the uncertainty of tie lines.

[0041] Furthermore, the independent balance carried out by each independent balance area using the new basic balance equation is called the new independent balance mode G o The new independent balance mode G o and the 4 new integrated balance engineering modes are further combined to form a new power system power balance mode set, and a new power system power balance panoramic space is constructed based on the new power system power balance mode set.

[0042] Compared with the prior art, the beneficial technical effects of the present invention are:

[0043] (1) On the basis of introducing probability theory and probability operation methods into power balance calculation, a new basic balance equation of algebraic configuration is deduced and constructed, realizing the same-dimensional quantitative control of balance risk and conventional balance elements, and simplifying the probabilistic power balance analysis process of independent balance areas.

[0044] (2) A probabilistic analysis and calculation method for the whole-network integrated balance (under the condition of inter-regional mutual assistance and support) based on numerical calculation and computing power is proposed to solve the difficult problems of analysis and solution after the coupling of "randomization" and "integration".

[0045] (3) The proposed method is combined with power balance engineering practice, and the coordination of balance within the power balance area and inter-regional mutual assistance and support is considered as a whole, and engineering application modes under specific balance objectives such as "ensuring power supply" and "promoting consumption" are proposed, laying a foundation for the engineering practical application of the present invention.

[0046] (4) The proposal of the new integrated balance equation adapts to the trend of the new power system balance mechanism towards a multi-region and multi-subject collaborative balance mode, expands the balance scope from a single balance area to the whole network, combines the problems of ensuring power supply and ensuring consumption, and makes theoretical preparations for overall optimizing and mutual assistance of the whole network resources. It adapts to the trend of the new power system balance mechanism towards a probabilistic balance mode, expands the balance category from the conventional algebraic balance to the joint balance of "algebra + random number", and realizes the joint quantitative calculation of balance uncertainty and the collaborative quantitative control of balance risk.

[0047] (5) Promote an essential change in the conventional reserve mode. In the conventional mode, the operation uncertainties and risks are difficult to quantify and measure. In engineering practice, reserves are introduced based on experience to cope with uncertainty risks. In the new integrated whole-network balance environment, especially after implementing the all-factor integrated balance, the balance risks of the system will be comprehensively and quantitatively reflected. The uncertainty is transformed from unknown to "knowable", and essentially realizes the "replacement" and "release" of conventional reserves. That is, promote the transformation of the conventional reserve mode to a "risk quantification control" mode.

[0048] (6) Promote the expansion of the balance analysis method for the new power system. Due to the widespread existence of uncertain factors, the current mainstream research method for the balance-related problems of the new power system is the production time series simulation method. Its essence is to regard the object to be analyzed as a natural uncontrolled quantity and a black box for simulation reproduction, without refining the key balance characteristics of the object to be analyzed. In the new integrated balance mode, the uncertain characteristics of all balance elements are quantitatively characterized, and the object to be analyzed is transformed into an "observable", "measurable", "controllable", and "decouplable" quantity, thus greatly improving the scientificity and effectiveness of the balance analysis method for the new power system. Description of the Drawings

[0049] Figure 1 It is the step flow chart of the method of the present invention;

[0050] Figure 2 It is the panoramic space diagram of the integrated balance of the new power system of the present invention;

[0051] Figure 3 It is the example network topology diagram of the present invention;

[0052] Figure 4 It is the statistical characteristic diagram of the prediction deviation rate of new energy in Balance Area B of the present invention;

[0053] Figure 5 It is the statistical characteristic diagram of the prediction deviation rate of the load in Balance Area C of the present invention;

[0054] Figure 6 It is the independent balance result diagram under the conventional and new basic balance principles of the present invention;

[0055] Figure 7 It is the balance adjustment situation diagram of Balance Areas A and B under the new basic balance principle of the present invention;

[0056] Figure 8 It is the probability distribution diagram of the balance margin of each balance area before and after the calculation of S of the present invention;

[0057] Figure 9 It is of the present invention and The comparison diagram of the new energy limited power curves of the whole network under the two balance modes;

[0058] Figure 10 For the present invention and Comparison diagram of the probability distribution of the balance margin in each balance area under two balance modes of the present invention;

[0059] Figure 11 Comparison diagram of the probability distribution of the balance margin in each balance area under single factor and all factors of the present invention;

[0060] Figure 12 Development curve of new energy penetration - curtailment rate under different balance principles of the present invention. Detailed implementation manners

[0061] In the description of the present application, the meaning of "a plurality of" is at least two, for example, two, three, etc., unless otherwise specifically defined. In the embodiments of the present application, all directional indications (such as up, down, left, right, front, back, top, bottom...) are only used to explain the relative positional relationship and movement conditions between components in a specific posture (as shown in the drawings). If the specific posture changes, the directional indications will change accordingly. In addition, the terms "include" and "have" and any variations thereof are intended to cover non - exclusive inclusion. For example, a process, method, system, product or Internet of Things terminal including a series of steps or units is not limited to the listed steps or units, but optionally further includes steps or units not listed, or optionally further includes other steps or units inherent to these processes, methods, products or Internet of Things terminals.

[0062] In addition, referring to "embodiment" in the present application means that a specific feature, structure or characteristic described in combination with the embodiment can be included in at least one embodiment of the present application. The phrase appears at various positions in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. Those skilled in the art explicitly and implicitly understand that the embodiments described in the present application can be combined with other embodiments.

[0063] Next, the technical solutions in the embodiments of the present application will be clearly and completely described with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art without creative efforts based on the embodiments in the present application belong to the scope of protection of the present application.

[0064] As Figure 1 shown in the step flow chart of the present application, the present invention provides a method for applying the power balance principle and engineering mode of a new - type power system, and the specific steps are as follows:

[0065] S1. Statistically calculate the probability density and probability distribution according to the random characteristic laws of the balance elements in each balance area; independently conduct initial balance for each balance area; set the balance target considering the requirements for the probability distribution of the balance margin of each balance area and the whole network.

[0066] S2. Based on the new basic balance principle during the power supply guarantee stage, construct a new basic balance equation in algebraic configuration.

[0067] S3. Based on the new integrated balance principle during the power supply guarantee stage, randomly transform the conventional integrated balance equation to construct a new integrated balance equation, and propose a solution method for the new integrated balance equation based on numerical calculation.

[0068] S4. Based on the new basic balance principle during the consumption promotion stage, formulate the new energy consumption strategies for each independent balance area, and determine whether there is large-scale new energy curtailment. If so, jump to step S5; otherwise, end.

[0069] S5. Based on the new integrated balance principle during the consumption promotion stage, determine whether to enter the integrated balance consumption promotion link. If so, enter the new integrated balance new energy consumption promotion engineering mode K o , and then make subsequent judgments; otherwise, end.

[0070] Among them, the specific steps of step S2 include the following steps:

[0071] S201. Each balance area independently sets the initial balance boundary and calculates the risk conversion factor of the independent balance area Construct a new basic balance equation in algebraic configuration.

[0072] S202. Determine whether the balance requirements are met. If so, jump to step S4; otherwise, jump to step S203.

[0073] S203. Determine whether the conventional means in the independent balance area have been exhausted. If so, jump to step S204; otherwise, adjust the balance boundary of the independent balance area and then return to the new basic balance equation to form a closed loop.

[0074] S204. Determine whether to enable integrated balance for power supply guarantee. If so, jump to step S3; otherwise, increase the load management measure amount and then return to the new basic balance equation to form a closed loop.

[0075] The steps of step S3 also include the following steps: Consider the probability distribution of the balance margin of each balance area and the whole network under the integrated balance environment, compare the calculation results of the solution method of the new integrated balance equation with the set balance target, and determine whether the balance requirements are met. If so, jump to step S4; otherwise, adopt the natural mutual assistance mode under the new integrated balance power supply guarantee engineering mode H o under the natural mutual assistance mode and the collaborative mutual assistance mode Adjust the balance boundary of the relevant balance area by any one of them, and then return to the new integrated balance equation to form a closed loop.

[0076] The subsequent judgment in step S5 specifically includes the following steps: judge whether the maximum promotion and absorption have been achieved. If so, adjust the new energy absorption strategy of each balance area; otherwise, adopt the new integrated balance promotion new energy absorption engineering mode K o under the natural mutual assistance mode and the collaborative mutual assistance mode Adjust the balance boundary of the relevant balance area by any one of them, and then return to the new integrated balance promotion new energy absorption engineering mode K o to form a closed loop.

[0077] Embodiment 1

[0078] To adapt to the objective law that the power and electricity balance mechanism of the new power system changes from the "source following load" mode to the probabilistic, multi-region, and multi-agent source-network-load-storage collaborative balance mode, a random variable is introduced into the conventional basic balance equation to construct a new basic balance equation. Taking the new energy with the strongest randomness and volatility as an example, in the new power system balance environment, it is expressed as:

[0079] n o = n + Δn o (2)

[0080] In the above formula, n o is the new energy output, which is a random variable (in this application, the superscript "○" represents a random variable), and is composed of the balance reference quantity n and the random deviation quantity Δn o relative to the reference quantity. Among them, Δn o The probability distribution of can be obtained by statistical methods and is expressed as:

[0081]

[0082] Referring to the conventional representation method in mathematical statistics, in this application, are used to represent the probability density and probability distribution of any random variable x o respectively (the same below). In the above formula, represent the probability density and probability distribution of the random variable Δn o respectively, represents the probability density and probability distribution function of Δn o . The above formula characterizes the random characteristics of Δn o and is the basic parameter of the basic balance element - new energy (n).

[0083] Substituting Equation (2) into Equation (1), the expression of the upper balance margin is converted to:

[0084] δ o = R + T + (n + Δn o ) - ρl + x (4)

[0085] As can be seen from Equation (4), after introducing the random variable Δn o , the upper balance margin δ is correspondingly converted to the random variable δ o . After substituting Equation (3) into Equation (4), the probability density and probability distribution of δ o can be obtained as:

[0086]

[0087] The physical meaning of Equation (5) is that after the various basic balance elements (R, T, n, l, x, etc.) participate in determining the balance reference quantity, the probability distribution of the balance margin is determined by the probability distribution of new energy; to adjust the probability distribution of the balance margin, some basic balance elements need to be adjusted (since n and l are natural uncontrollable quantities, generally the controllable quantities such as R, T, and x need to be adjusted).

[0088] Based on Equation (5), the constraint of the upper balance margin is converted from δ≥0 in Equation (1) to the following constraint:

[0089]

[0090] The physical meaning of Equation (6) is that the probability that the balance margin δ o is less than the threshold δ Λ is less than λ Λ . In Equation (6), (δ Λ , λ Λ ) characterizes the balance risk control requirements, reflects the balance risk, and this application refers to Equation (6) as the balance risk control equation.

[0091] In practice, generally no balance risk defense is set for the lower balance margin (such as no lower balance reserve is reserved in the conventional balance mode), so the lower balance margin equation is not probabilistically processed. Then the basic balance equation is converted from Equation (1) in the conventional mode to Equation (7):

[0092]

[0093] The first set of equations in Equation (7) is an equality constraint, which characterizes the correlation relationship of each balance element (the first and second sub - equations) and the statistical characteristics of the random quantity (the third sub - equation); the second set of equations is an inequality constraint, which characterizes the balance boundary requirements. This application refers to Equation (7) as the new basic balance equation.

[0094] Further derivation from equations (5) and (7) gives:

[0095]

[0096] In equation (8), is the inverse function of. Based on equation (8), equation (7) is rearranged as:

[0097]

[0098] Equation (9) is the new balance equation applicable to the independent balance region. From a mathematical form perspective, equation (9) converts the probability equation containing random variables into a conventional algebraic equation. All balance elements in equation (9) are explicitly expressed, creating conditions for the analytical analysis of balance characteristics and the design and formulation of balance strategies in the independent balance region. The key to converting the random quantity into an algebraic quantity in equation (9) is Its physical meaning is to convert the balance risk into a balance control quantity, called the risk conversion factor.

[0099] Example 2

[0100] In the integrated balance mode, the basic balance equation is converted from equation (1) into the following conventional integrated balance equation:

[0101]

[0102] In the above equation, each variable is a vector composed of the corresponding balance element sets of the whole network balance region set and the channel set. Among them, Δs is the mutual aid power set, and δ 0 is the initial upper balance margin before mutual aid; M and N are the structure matrices for mapping the mutual aid power Δs to the balance region set and the channel set respectively; H S is the integrated power supply optimization mutual aid process constrained by the initial balance conditions of each balance region, the limits of each channel, the power distribution rules, etc. It generates the mutual aid power set Δs between balance regions. Here, it is simplified and referred to by the implicit function H S Its mechanism of action and mathematical expression will be specifically explained below.

[0103] Introduce random variables (here, new energy is selected as the random quantity) into the conventional integrated balance equation to form a new integrated balance equation:

[0104]

[0105] In the above equation, the new energy deviation (Δn o ), the balance margins before and after mutual aid ( δ o ), the mutual aid power (Δs o) etc. are all converted into random variables; without considering the random characteristics of the lower balance margin σ, σ is controlled as an algebraic variable in the balance mode arrangement.

[0106] Different from the conventional integrated balance equation, the inequality constraint of the upper balance margin in the new integrated balance equation changes. The balance risk control mode (Equation (6)) is adopted, where the first sub-formula of the inequality group is the risk control sub-equation group for each balance area; the second sub-formula is the network-wide risk control equation, and ΔX o is the network-wide balance gap, and its physical meaning is that the probability that the network-wide balance gap is less than ΔX Λ is greater than λ Λ . This application calls Equation (11) the new integrated balance equation.

[0107] Furthermore, the solution process of the new integrated balance equation can be divided into two types: mathematical analysis method and numerical calculation method. Among them, the mathematical analysis method is as follows:

[0108] From Equation (7), it can be known that the initial upper balance margin before mutual assistance is:

[0109]

[0110] Derived from Equations (11) and (12):

[0111]

[0112] Equation (13) shows that the random variable Δs o is a function of the random variable Δn o . Substituting Equation (13) into the first sub-formula of the equation group in Equation (11) continuously, it can be known that:

[0113]

[0114] From Equation (14), it can be known that δ o is also a function of the random variable Δn o ; where Δn o is a random vector composed of new energy deviation random variables in each balance area, and its joint probability density is:

[0115]

[0116] In Equation (15), is the new energy deviation random variable of any balance area, is the corresponding probability density function, is the joint probability density of the random vector Δn o . Then, derived from Equations (14) and (15), the random vector δ oThe joint probability density is as follows:

[0117]

[0118] In Equation (16), is the function δ o = S δ (Δn o ) is the inverse function segment, and Γ is the set of all function segments that may be formed after inverting the function S δ after inversion, is the joint probability density function of Δn o .

[0119] Theoretically, if the analytical solution of can be obtained through Equation (16), the algebraic expression of the new integrated balance equation can be constructed with reference to Equations (8) and (9), thus greatly facilitating the characteristic analysis of integrated balance and the design of control strategies. However, different from the risk conversion factor of the independent balance area being an explicit function, the risk conversion factor of the new integrated balance equation is generated by H S (the process of natural mutual assistance for ensuring supply), which is a complex overall optimization process with multiple constraints, that is, is a complex implicit function of Δn o , and the analytical result cannot be obtained.

[0120] Therefore, this application proposes to solve through numerical calculation and calls the entire solution process the S calculation process. The complete S calculation process consists of three links: "decomposition", "calculation", and "induction".

[0121] Among them, the "decomposition" link is as follows: The random vector Δn o is decomposed into discrete sample vectors in the full-dimensional and full-probability space. Any sample vector Δn ξ after decomposition is expressed as:

[0122]

[0123] In Equation (17), Δn ξ is an N-dimensional vector, represents the complete set of samples after decomposition; is the value of the k-th dimension in the vector Δn ξ , and represents the sample subset of the vector Δn ξ in the k-th dimension. Through Equation (17), an N-dimensional random variable Δn o is decomposed into ( is the number of samples in

[0124] For any sample Δn ξ Its probability is as follows:

[0125]

[0126] In Equation (18), is the probability distribution function of the new energy deviation in the k-th balance area and is a basic statistical parameter. That is, through Equations (17) and (18), the unknown variable (Δn o ) is converted into a definite numerical space ((Δn ξ , )) as shown in Equation (19):

[0127]

[0128] The "calculation" process is as follows: For any sample vector Δn ξ Substitute it into Equation (10) to perform the whole-network integrated balance calculation,

[0129]

[0130] In Equation (20), the new energy is converted from n to n + Δn ξ ; H S is the natural optimization and mutual assistance process, and its complete process is determined by the optimization process determined by Equations (21) and (22).

[0131] (1) Objective function

[0132]

[0133] In Equation (21), is the set where the upper balance margin after integrated balance is less than zero, is 's modulus. The physical meaning of Equation (21) is to minimize the whole-network balance gap to the greatest extent.

[0134] (2) Constraints

[0135]

[0136] In Equation (22), the first and second equalities are the upper balance margins before and after mutual assistance; the third equality characterizes the influence of the mutual assistance power Δs on the channel power, where P b0 , P b are the channel power sets before and after mutual assistance, and N is the mapping matrix from Δs to the channel set; the fourth equality characterizes the power distribution rule set during the mutual assistance process. The first inequality requires reasonable control of Δs and prohibits creating a balance gap in a balance area without a gap. The superscript "+" represents the balance area where the initial balance margin is greater than zero; the second inequality is the channel limit constraint during the mutual assistance process.

[0137] Through equations 20 - 22, the sample Δn can be obtained ξ The balance margin δ of each balance area after integrated balance under the boundary ξ , since Δn ξ and δ ξ have an inevitable causal relationship, their probabilities are the same, that is:

[0138]

[0139] Thus, the integrated balance margin δ corresponding to this object sample is obtained ξ probability.

[0140] The "induction" process is as follows: For all samples within , integrated balance calculations are carried out, and the probability space of the corresponding integrated balance margin set can be obtained, that is:

[0141]

[0142] After the "calculation" process, the obtained (δ ξ , ) are disordered, cluttered and overlapping, and they still need to be integrated, inductively sorted to obtain the balance margin δ o joint probability density function, that is:

[0143]

[0144] Based on the joint probability density in equation (25), the balance margin probability density of any balance area k can be calculated as:

[0145]

[0146] Thus, the numerical solution of the new integrated balance equation is realized. In practice, in addition to having risk control requirements for each balance area, the overall balance risk of the entire network also needs to be controlled. Therefore, it is necessary to further obtain the network gap ΔΦ o probability distribution on the basis of equation (26). The mathematical relationship between ΔΦ o and δ o is shown in equation (27).

[0147]

[0148] In equation (27), ΔΦ o is the weighted negative balance margin of all balance areas with a balance margin less than zero (there is a balance gap), and its physical meaning is the total network balance gap.

[0149] For the convenience of discussion, the above complete process is referred to by equation (28),

[0150]

[0151] In Equation (28), the first sub - expression is a simplified representation of the process of the balance margin of each balance area in the integrated solution of the balance equation, indicating the key variables affecting the solution result, including the basic statistical characteristics of the new - energy deviation as well as the start - up of conventional power sources R, the planned power of tie - lines T, etc., denoted by S o ; the second sub - expression is a simplified representation of the process of calculating the probability distribution of the network gap, indicating that it is a further calculation carried out based on the solution results of the balance margin of each balance area and is denoted by S ∑ .

[0152] Embodiment 3

[0153] In the above derivation, for the convenience of analysis, only the uncertain characteristics of new energy with the strongest randomness and volatility are introduced temporarily; in the environment of a new - type power system, there are also uncertainties to a certain extent in balance elements such as load, conventional power sources, planned power of tie - lines, and load management measures. For example, situations such as outages and faults of conventional power sources and tie - line channels in actual operation. After introducing the uncertain characteristics of all balance elements, Equation (4) will be expanded to:

[0154] δ o =R + T + n-ρl + x+(Δn o +Δl o +ΔR o +ΔT o +Δx o )(29)

[0155] In Equation (29), Δl o , ΔR o , ΔT o , Δx o respectively represent the random deviation amounts of load, conventional - power - generation capacity, planned power of tie - lines, and load management measures.

[0156] The integrated balance carried out based on Equation (29) is the all - element integrated balance of the new - type power system. It can be divided into the following two types according to whether the uncertainty of tie - lines is considered:

[0157] 1. All - element integrated balance without considering the uncertainty of tie - lines

[0158] Without considering the uncertainty of tie - lines, for the uncertainties of each element in the balance area, they can be combined and processed according to statistical methods, that is:

[0159]

[0160] In Equation (30), ΔΩ oIt is the comprehensive deviation of each balance element in the area. From Equation (30), we know that ΔΩ o has a summation relationship with the deviation of each balance element in each area. Therefore, ΔΩ o 's probability density can be obtained by convolving the probability densities of the deviation amounts of each balance element in the area, that is:

[0161]

[0162] Equation (31) is the convolution calculation process. Substituting Equations (29) and (31) into the new integrated balance Equation (11), the all-element integrated balance equation can be constructed; the corresponding balance margin calculation process (S process) is correspondingly converted to:

[0163]

[0164] Compared with Equation (28), Equation (32) adjusts the key parameter from to

[0165] 2. All-element integrated balance considering the uncertainty of tie lines

[0166] Further introduce the tie line deviation amount ΔT o in Equation (30), then the balance margin formula for a single balance area is extended to:

[0167] δ o = R + T + n - ρl + x + ΔΩ o + ΔT o (33)

[0168] In Equation (33), ΔT o not only directly acts on the target balance area, but also affects the channel capacity of other balance areas and the integrated balance process. Therefore, it cannot be incorporated into the total deviation of a certain balance area in the form of convolution as in Equation (31). Therefore, Equation (33) treats ΔT o , ΔΩ o as two independent random variables. After substituting Equation (33) into the integrated balance Equation (11), the expression of its upper balance margin can be obtained as:

[0169]

[0170] Based on Equation (34), and then obtained by the numerical calculation method of "decomposition - calculation - induction" Among them, Equation (15) will be adjusted to:

[0171]

[0172] Compared with Equation (15), the sample decomposition range of Equation (35) is extended from Δn o to ΔΩ o ×ΔT o (where the subscript B represents the number of tie-line channels). Accordingly, the corresponding balance margin calculation process (S process) is transformed into:

[0173]

[0174] Equations (34) and (36) are the key equations for the all-factor integrated balance.

[0175] Example 4

[0176] Based on the new integrated balance equation, considering the differences in the balance objective, balance means, and balance process, the basic mode of the new integrated balance project is summarized as follows:

[0177] 1. Power supply guarantee mode (H o mode)

[0178] In the power supply guarantee mode, the balance objective is to overall minimize the amount of load management measures for the entire network. According to whether to adjust the unit startup across the balance area, it is divided into two cases: the natural mutual assistance mode ( mode) and the collaborative mutual assistance mode .

[0179] (1) Natural mutual assistance mode ( mode)

[0180] The natural mutual assistance mode is characterized by the following optimization process

[0181] Objective function:

[0182] f = min(|Δx|) (37)

[0183] In Equation (37), Δx is the vector composed of the load management measure amounts of each balance area in the entire network, |Δx| is the modulus of Δx, and the physical meaning of Equation (37) is to minimize the total load management measure amount of the entire network.

[0184] Equality constraint:

[0185]

[0186] In the first set of equations in Equation (38), the two sub-formulas respectively represent the balance margins on the balance areas before and after the integrated balance (the subscript "v" represents before the integrated balance, and the subscript "u" represents after the integrated balance, the same below); the second set of equations is the probability calculation equation, and the three sub-formulas are respectively the probability density of the partition balance margin before the integrated balance, the probability density of the partition balance margin after the integrated balance, and the probability density of the network-wide gap after the integrated balance. It should be noted that the core control variable in this mode is: Δx.

[0187] Inequality constraints:

[0188]

[0189] If then Δx + = 0; (40)

[0190] The inequality constraints are composed of Eqs. (39) and (40). Eq. (39) is the balanced risk constraint, where the first sub - expression is the balanced risk constraint for each balance area, and the second sub - expression is the network - wide balance gap constraint; Eq. (40) is the fairness constraint, and the subscript “+” represents the balance area where the initial balance margin meets the risk control requirements (i.e., ). Its physical meaning is that in the integrated balancing process, the balance areas with initial balance margins meeting the requirements cannot take load management measures anymore.

[0191] Summary of logical relationships:

[0192]

[0193] The above - mentioned mode can be generally characterized by Eq. (41). The left - most term is the key initial variable before integrated balancing, the middle Δx is the key control variable, and the right - most term is the key result variable. It can be seen that its core physical meaning is: based on the basic principle of the new integrated balancing (S o ), seek the minimum control cost of Δx to meet the probabilistic risk control requirements.

[0194] This application uses to represent the complete process of the above - mentioned natural mutual - assistance mode for ensuring power supply.

[0195] (2) Cooperative mutual - assistance mode

[0196] The cooperative mutual - assistance mode is characterized by the following optimization process,

[0197] Objective function:

[0198] f = min(|Δx|) (42)

[0199] In this mode, the objective function is the same as that of mode.

[0200] Equality constraints:

[0201]

[0202] Compared with the equality constraints of the process, in this mode, the key control variables are extended from Δx to two: Δx and ΔR, where ΔR is the adjustment amount of the conventional power supply startup in each balance area.

[0203] Inequality constraint:

[0204]

[0205]

[0206] Compared with the inequality constraint of the process, an additional unit start-up constraint in the balance area is added in this mode, that is, it is required that the unit start-up capacity does not exceed the maximum start-up capacity (R max ).

[0207] Summary of logical relationships:

[0208]

[0209] The main logical relationship of the above mode is characterized by Equation (46). Compared with Equation (41), its key control variable increases by ΔR, and ΔR and Δx are in a serial order relationship; its complete process "nests" mode. It can be seen that its core physical meaning is: on the basis of the principle of natural mutual assistance for power supply guarantee, by reasonably adjusting the start-up scale of each balance area, the minimum control cost of Δx is sought to meet the requirements of probabilistic risk control.

[0210] This application uses to represent the complete process of the above-mentioned collaborative mutual assistance mode for power supply guarantee.

[0211] 2. New energy consumption promotion mode (K o mode)

[0212] Under the new energy consumption promotion mode, the balance goal is to minimize the limited power of new energy in the whole network. Similarly, it is divided into two cases: natural mutual assistance mode ( mode) and collaborative mutual assistance mode according to whether to adjust the start-up across balance areas .

[0213] (1) Natural mutual assistance for consumption ( mode)

[0214] Objective function:

[0215] f = min(|Δy|) (47)

[0216] In Equation (47), Δy is a vector composed of the limited power of new energy in each balance area of the whole network, |Δy| is the modulus of Δy, and the physical meaning of Equation (47) is: to minimize the limited power of new energy in the whole network.

[0217] Equality constraint:

[0218] ​Considering the actual engineering situation, it is considered that the initial positive balance margin for promoting new energy consumption has been greater than zero. Its equality constraints are shown in Eqs. (48 - 50).

[0219]

[0220]

[0221] Among them, Eq. (48) is the lower balance margin equation, where σ v is the initial lower balance margin, σ u is the lower balance margin after integrated balancing, and σ u increases by two key control variables compared to σ v : the limited power of new energy Δy and the mutual assistance power for consumption Δs K . Eq. (49) is the upper balance margin equation, whose principle and configuration are the same as Eqs. (38) and (43), except for differences in the composition of specific elements. For example, compared with Eq. (38), Eq. (49) lacks the control variable - the load management measure Δx and has an additional control variable - the mutual assistance power for consumption Δs K . Eq. (50) is the constraint for the mutual assistance process for consumption. The first sub - equation is the expression of the channel power before and after mutual assistance, where P bv , P bu are the channel power vectors before and after mutual assistance respectively, and N u is the mapping matrix of the impact of the path mutual assistance power on the channel power; the second sub - equation is the constraint of the power distribution rule set, which characterizes the order of rules followed during the adjustment of the mutual assistance power for consumption.

[0222] Inequality constraints:

[0223]

[0224] Eqs. (51 - 53) constitute the inequality constraints of this mode. Among them, Eq. (51) is the upper balance margin constraint, and its physical meaning is the same as Eqs. (39) and (44). Eq. (52) is the lower balance margin constraint. The physical meaning of the first sub - equation is that the lower balance margin must be greater than zero after the mutual assistance process; the physical meaning of the second sub - equation is that the locally limited power of new energy in each balance area cannot be negative; the physical meaning of the third sub - equation is that for the balance area where new energy curtailment is not implemented in the initial state (i.e., ), new energy curtailment cannot occur during the mutual assistance process, and the superscript “+” represents the balance area with an initial lower balance margin greater than zero; among the above constraints, the first sub - equation is a physical constraint, and the second and third sub - equations are fairness constraints. Eq. (53) is the channel power limit constraint, where are the upper and lower limits of the channel respectively.

[0225] Summary of logical relationships:

[0226]

[0227] The main logical relationship characterizing the above - mentioned pattern is summarized by formula (54). Compared with (formula (41)), the key initial variables and result variables (i.e., target variables) are reduced by the load management measure quantities (x, Δx), and increased by the lower balance margin (σ v 、σ u ) and the new - energy - limited power (y, Δy); its key control variable is adjusted from Δx to Δy and Δs K . It can be seen that its core physical meaning is: on the basis of the new integrated balance basic principle (S o ) and on the premise of meeting the upper balance margin constraint (i.e., meeting the probabilistic risk - control requirements), by reasonably adjusting the mutual - assistance power Δs K in the balance interval, the minimum control cost of Δy is sought to meet the lower balance margin constraint.

[0228] This application uses to represent the complete process of the above - mentioned natural mutual - assistance mode for promoting new - energy consumption.

[0229] (2) Consumption coordination and mutual assistance ( mode)

[0230] Objective function:

[0231] f = min(Δy) (55)

[0232] Equality constraints:

[0233]

[0234] Formulas (56 - 58) constitute the equality constraints of this mode. The configuration is the same as that of formulas (48 - 50). The main difference is that the control variable ΔR is added, that is, the control variables are expanded from two, Δs K 、Δy, to three: ΔR, Δs K and Δy.

[0235] Inequality constraints:

[0236]

[0237] Formulas (59 - 61) constitute the inequality constraints of this mode. Compared with 's inequality constraints (formulas (51 - 53)), the minimum - start - up constraint of the balance area (the second sub - formula in formula (61)) is added, that is, the unit adjustment in each balance area cannot exceed the minimum start - up range, and R min is the minimum start - up of each balance area.

[0238] Summary of logical relationship:

[0239]

[0240] The main logical relationship of the above - mentioned pattern is generally characterized by Equation (62). Compared with Equation (54), its key control variable increases by ΔR, and ΔR has a serial order relationship with (Δx, Δs K ); its complete process "nests" patterns. It can be seen that its core physical meaning is: on the basis of absorbing the principle of natural mutual assistance and satisfying the upper balance margin constraint (that is, meeting the requirements of probabilistic risk control), by reasonably adjusting the starting - up scale of each balance area, the minimum control cost of Δy is sought to meet the lower balance margin constraint.

[0241] This application uses to represent the complete process of the above - mentioned collaborative mutual - assistance pattern for promoting new - energy consumption.

[0242] Example 5

[0243] The basic principle of the new - type integrated balance has been systematically explained above. In practice, the power - balance process is a complete process evolving over time. It is necessary to consider the integrated balance of each region within any time section horizontally and the correlation constraints between time sections vertically, that is, to carry out spatio - temporal joint calculations. Compared with the basic principle, the spatio - temporal joint calculation mainly has the following three characteristics:

[0244] (1) Objective - function adjustment. The objective function is still unique, but it is converted from a single - time - section variable to a comprehensive benefit quantity of multiple time sections. For example, when ensuring power supply, it can be the maximum - load management measure quantity of the whole network throughout the day, and when promoting consumption, it is the total new - energy curtailment quantity of the whole network throughout the day.

[0245] (2) Increase in constraint dimensions. The constraint equations will be extended from a group at any time section to multiple groups equal in number to the number of time sections.

[0246] (3) Addition of cross - time - section constraints. For example, affected by the unit starting - up time, the starting - up scale cannot be adjusted quickly and frequently, and the unit starting - up capacity remains relatively stable within multiple time sections.

[0247] Combined with engineering practice, a set of engineering models and a panoramic space for power balance in the new - type power system are constructed. In engineering practice, the 4 new - type integrated balance basic models and the new - type independent balance model (G o ) mentioned in this application can be further combined and applied to meet the needs of different scenarios, and the model set formed is shown in Table 1.

[0248] Table 1 New - type power - system power - balance model set

[0249]

[0250] In Table 1, G​o It is a new independent balance mode, that is, each independent balance area conducts independent balance by using the new basic balance equation (Equation (9)). Its implementation process is the simplest, but it does not meet the needs of the integrated large-scale production of the new power system; It is an ideal type, which can call all resources of the whole network to maximize the overall planning of power supply guarantee and consumption, but the implementation difficulty is also the greatest.

[0251] According to the new integrated balance mechanism, its solution optimization process is extremely complex. In this application, the calculation time is estimated by the empirical formula (63):

[0252] T Σ ≈N type ×N T ×Q V ×ΔT (63)

[0253] In Equation (63), ΔT is the reference time; N type is a mode parameter. Under the same other conditions, the overall calculation amount increases; N T is the number of time sections; Q is the element resolution. The larger Q is, the more detailed the sample statistical characteristics are. When Q→∞, the sample probability distribution will tend to a continuous function; V is the number of balance areas. From Equation (63), it can be seen that the existence of the Q V term means that the calculation amount will increase explosively with the increase of the resolution and the number of balance areas, resulting in the "curse of dimensionality".

[0254] Therefore, an engineering inference is obtained: The basis of the engineering practice of the new integrated balance mechanism is "computing power". Only with sufficiently powerful computing power can it support the comprehensive, efficient and refined integrated balance of the new power system, and only then can it discover the core balance laws in the complex coupling relationships and ubiquitous uncertain elements of the new power system like "mining", so as to scientifically guide the balance of the new power system and serve the new national energy transformation and development strategy.

[0255] This application summarizes the development space and evolution path of the new power system balance mode with the power balance panoramic space of the new power system. As Figure 2 shown, the X-axis is the random element axis, which represents the change of the random element space. The random elements participating in the balance are gradually enriched along the axis; the Y-axis is the integrated balance coverage rate axis, which represents the proportion (coverage rate) of the balance areas of the whole network participating in the integrated balance. The coverage rate increases along the axis; the Z-axis is the balance mode axis, which represents the refinement degree of the balance mode. The balance mode is continuously refined and improved along the axis. The three-dimensional space composed of the X-Y-Z three dimensions is the development space of the new power system integrated balance mode. It can be seen that during the construction process of the new power system, various balance states (at different positions in the panoramic space) may appear. From Figure 2It can be seen that: (1) In the context of the new power system, the balance mode will evolve from low to high in the integrated balance panoramic space ( Figure 1 the red dotted line in), gradually transitioning from the algebraic balance in independent balance areas to the balance of the entire network, all elements, and probability. (2) Along with the development of the integrated balance mode, there is an explosive growth in the computing power demand ( Figure 1 the blue dotted line in), so the key to promoting the development and evolution of the integrated balance mode is to solve the computing power problem.

[0256] Example 6

[0257] 1. Illustration of the calculation example

[0258] This calculation example refers to the actual regional power grid structure, and the topology is as Figure 3 shown. The calculation example consists of six balance areas from A to F and five channels from 1 to 5, and a total of 30 power mutual aid paths are derived.

[0259] Taking the actual power production data (including load, new energy output, planned power of tie lines, etc.) of a typical day of the corresponding power grid as a reference, the initial balance conditions of the calculation example are constructed.

[0260] Based on the statistical analysis of the true historical power generation data of new energy in each balance area, the basic characteristic curve of new energy participating in power balance as a random variable is constructed through mathematical statistics and probability theory methods. Since the benchmark quantities of new energy participating in balance in the medium and long-term and day-ahead power balance dimensions are different (in the medium and long-term dimension, there is no specific predicted output of new energy, and the installed capacity of new energy is used as the benchmark quantity participating in power balance; in the day-ahead dimension, there is a specific predicted output of new energy, and the predicted output of new energy is used as the benchmark quantity participating in power balance).

[0261] This application's calculation example takes the day-ahead power balance as an example, and uses the statistical law of the prediction deviation rate of new energy output to characterize the random characteristics of new energy. For example, the random characteristics of new energy in balance area F are as Figure 4 shown.

[0262] This application's calculation example takes the day-ahead power balance as an example, and uses the statistical law of the prediction deviation rate of load to characterize the random characteristics of load. For example, the random characteristics of load in balance area C are as Figure 5 shown.

[0263] 2. New basic balance principle

[0264] Under the independent balance mode, when the balance boundary conditions are the same, the balance results of the six balance areas from A to F using the conventional basic balance principle and the new basic balance principle are respectively as Figure 6 shown; among them, the blue dotted line is the balance margin calculated using the conventional basic balance principle, and the black solid dots and their connecting dotted lines are the balance margins calculated using the new basic balance principle. From Figure 6It can be known that: (1) Under the conventional basic balance principle, the balance margin is a fixed algebraic quantity (the horizontal axis value indicated by the blue dotted line), and under the new basic balance principle, the balance margin becomes a random variable (for the convenience of analysis, the random distribution is aggregated into 7 points / segments, and the dotted line is used to connect them to characterize its distribution change law); (2) Under the conventional basic balance principle, the balance margins of each balance area are all greater than 0 (the specific values of the balance margin are shown in the first row of Table 2). Under the new basic balance principle, the balance margins of balance areas A to E have a probability distribution within the positive and negative intervals, and the probability of balance area F is all distributed in the interval greater than 0. That is, the calculation conclusion using the conventional basic balance principle is that there is no balance gap, and the calculation conclusion using the new basic balance principle is that there is a certain probability of balance gap in balance areas A to E.

[0265] It can be seen from this that the balance margin calculated using the conventional basic balance principle is unreliable and there may be balance risks, as shown in Table 2. Taking balance area A in Table 2 as an example, under the conventional basic balance principle, its balance conclusion is that there is not only no balance gap but also a balance margin of 110 MW; under the new basic balance principle, its balance conclusion is that there is a 38% probability of balance gap, and the maximum possible balance gap is 2902 MW.

[0266] Table 2 Balance Margin / Risk Calculated by Conventional and New Basic Balance Principles

[0267]

[0268] Under the new basic balance principle, it is necessary to adjust the controllable balance elements (usually the starting capacity of conventional power sources in the independent balance mode) according to Equation (9) to eliminate the balance risk. Taking balance areas A and F as examples, setting the adjustment target to "zero risk", the adjustment results are as Figure 7 shown.

[0269] Figure 7 In, after increasing the starting units in balance area A (increasing by 2900 MW), the probability distribution of the balance margin in balance area A as a whole shifts to the right (positive direction). The probability distribution of the adjusted balance margin (the blue solid dots and their corresponding connecting lines in the figure) all fall within the positive value interval, that is, the adjusted balance margin is greater than 0 with a 100% probability, thus achieving "zero risk"; the initial probability distribution of the balance margin in balance area F all falls within the positive value interval, that is, the balance results calculated by both the conventional and new basic balance principles are "zero risk", so its controllable balance elements are not adjusted.

[0270] 3. New Integrated Balance Principle

[0271] 3.1 Solution of the New Integrated Balance Equation (S o Calculation)

[0272] Numerically solve the new integrated balance equation of the example (S o calculation), after S o calculation, the probability distributions of the balance margins in each balance area are as Figure 8 shown, where the black dots and red triangle dots are the probability distributions of the balance margins in each balance area before and after S o calculation respectively. It can be seen from Figure 8 that:

[0273] (1) For the balance areas (A to E) with balance risks, after S o calculation, the overall probability distribution of the balance margin has shifted towards the positive direction. For example, after S o calculation, the probability distributions of the balance margins in balance areas D and E all fall within the positive value range. It shows that: S o calculation overall reduces the balance risk of the whole network.

[0274] (2) For the balance area without balance risk, after S o calculation, the probability distribution of the balance margin has shifted towards the negative direction, but still all fall within the positive value range. It shows that: S o calculation reasonably adjusts the probability distribution.

[0275] (3) Different from the new basic balance principle (performing an overall translation of the probability distribution curve without changing the curve shape), before and after S o calculation, the characteristics (curve shape) of the probability distribution of the balance margin have changed significantly and irregularly. It shows that: compared with the linear equations of the new basic balance principle, the new integrated balance equation and its S o settlement results are more complex; it also verifies the assertion in this application that the new integrated balance equation is difficult to analyze and needs to be solved by numerical calculation methods.

[0276] Thus, the solution of the new integrated balance equation of the example is achieved, and the solution results are consistent with the theoretical analysis expectations. Theoretical research combined with example analysis shows that the S o process of the new integrated balance optimizes and adjusts the probability distributions of the balance margins in each balance area through the mutual support ability between balance intervals, thereby reducing the balance risk of the whole network. It should be noted that the S o process only calculates the probability distributions of the balance margins in each balance area based on the new integrated balance principle, and does not make actual physical adjustments to the unit startup and tie-line power in each balance area; that is, S o plays a role similar to an "observation window" and a "solver" within the system of the new integrated balance principle.

[0277] 3.2 Power supply guarantee collaborative mutual assistance mode

[0278] In S oBased on the calculation, continue to implement coordinated mutual assistance for power supply in the example After that, the increased capacity of the units in each balance area is shown in Table 3. In Table 3, the first row is the increased capacity of the units required in each balance area under the new basic balance principle independent balance G o mode, and the second row is the increased capacity of the units required in each balance area under the new integrated balance principle mode. The balance boundaries and balance objectives (zero risk) of G o and are the same.

[0279] Table 3 Increased capacity of the units under the two balance modes of G o and

[0280]

[0281] From the data in Table 3, it can be seen that compared with the G o mode, the increased capacity of the units in the mode is significantly reduced. The increased capacity of the units in the whole network under the o mode is 3900 MW less than that under the G mode (a reduction of 59%). Especially in balance areas D and E, no additional units need to be started after adopting the mode. The significant reduction in the starting capacity means a significant reduction in the operating cost, indicating that: o is more economical and efficient than G, and also reflects the advantages of integrated balance.

[0282] 3.3 Ideal mode

[0283] According to the discussion of the engineering practice mode in this application, carry out the ideal new integrated power balance in the example environment Taking as the comparison reference, the results are as shown in Figure 9 , 10 and Table 4.

[0284] Figure 9 is the power curve of new energy limited in the whole network. The solid line in the figure corresponds to the mode, and the dotted line corresponds to the mode. It can be seen from the figure that the new energy limited power under the mode is significantly lower than that under the mode, that is, promotes the consumption of new energy. Figure 9 The results of intuitively reflect the value of

[0285] Table 4 is ​ For the adjustment of the starting capacity of each balance area in the two modes, it can be seen that: different from unidirectional increase, it is adjusted bidirectionally and overall among each balance area without an intuitive pattern. The bidirectional adjustment reflects the overall consideration of the power supply guarantee demand and the new energy consumption demand, which is consistent with the theoretical analysis expectation; the complex adjustment without an intuitive pattern indicates that the mode is more refined and complex than the

[0286] Table 4 and the increased capacity of the units under the two balance modes

[0287]

[0288] Figure 10 is the probability distribution of the balance margin of each balance area under the two modes. The red triangular points in the figure correspond to the blue square points correspond to From Figure 10 it can be seen that:

[0289] (1) Under the two modes, the probability distributions of the balance margins of each balance area all fall within the positive value range, that is, the "zero-risk" goal is maintained;

[0290] (2) Both balance modes have made significant irregular adjustments to the probability distribution characteristics of the initial balance margin ( Figure 6 the curve shape shown), and the differences between them are obvious, further reflecting the complexity of the new integrated balance principle, and also indirectly verifying the assertion of this application regarding the new integrated balance relying on numerical calculation and even computing power;

[0291] (3) Compared with , the probability distribution of the balance margin of shifts to the left overall, and the expected value of the balance margin decreases accordingly. This is the "reasonable price" paid to promote new energy consumption.

[0292] The above results generally show that on the basis of the new integrated balance principle, by optimizing and controlling the probability distribution of the balance margin of each balance area, the comprehensive goals of zero-risk balance and maximizing the promotion of new energy consumption are achieved, which is consistent with the theoretical analysis expectation.

[0293] 4. Example of the new integrated power balance with all elements

[0294] According to the discussion of the new integrated power balance principle of all elements in this application, without considering the uncertainty of tie lines for the time being, single-element (only treating new energy as a random variable) and all-element (treating new energy, load, and conventional power generation capacity as random variables) are respectively adopted to carry out The results are as Figure 11 shown in Table 5.

[0295] Table 5 Additional capacity of units under single-element and all-element balance modes

[0296]

[0297] Figure 11 For the comparison of the probability distributions of the balance margins of each balance area under the single-element and all-element modes before integrated balance, it can be seen from the figure that:

[0298] (1) Under the all-element and single-element modes, the probability distributions of the balance margins of each balance area are significantly different, indicating that the scope of random elements included in the balance greatly affects the basic parameters of the new integrated power balance.

[0299] (2) Compared with the single-element mode, the probability distributions of the balance margins of each balance area under the all-element mode generally shift to the left (negative direction), indicating that the more random elements are considered, the greater the balance risk.

[0300] It can be further known from Table 5 that due to the increase in the basic balance risk, more units need to be started up in the all-element integrated power balance mode to suppress the risk. In the example, the all-element mode needs to start up 950 MW more units than the single-element mode (an increase of 34.5%).

[0301] It should be noted that as described in this application, in current engineering practices, the balance risks of random elements such as load and conventional power reliability are generally suppressed by reserving a certain proportion of load and accident reserve. Based on this, it is considered that "single new energy random element integrated power balance + conventional reserve", "all-element integrated power balance - conventional reserve", etc. are all reasonable and feasible modes.

[0302] 5. Significance of computing power

[0303] Under the same software and hardware computing platform environment, the balance area number of the example and the resolution after aggregation of the random quantity probability distribution are respectively changed, and the statistical computing time is shown in Table 6.

[0304] Table 6 Computing time (seconds) of the example model with different resolutions and balance area numbers Computing time (seconds)

[0305]

[0306] As can be seen from Table 6, the computing time generally shows an exponential growth characteristic with the number of balance areas used in the model, the aggregation resolution of the probability distribution of random variables, etc. For example, in the example in 4.3.2, the number of balance areas is 6 and the resolution is 7, and the corresponding computing time is 1591 seconds (bold marked in Table 5, 27 minutes); when the number of balance areas increases to 7 and the resolution increases to 9, the corresponding computing time soars to 66978 seconds (18.6 hours). Considering the requirements of model complexity, fineness and timeliness faced by the new power system engineering practice, the computing power studied in this application is far from meeting the needs of large-scale practical applications.

[0307] The above results exemplify the discussion in this application about the significance of computing power, that is: the new integrated power balance will be a balance based on computing power. To "see clearly and adjust accurately", it is necessary to "calculate a lot and calculate quickly".

[0308] 6. Significance of the Principle of New Integrated Power Balance

[0309] Based on the actual production and operation data of a certain regional power grid in a certain year to which the example belongs, carry out simulation calculations on the correlation growth relationship between the new energy penetration rate / new energy curtailment rate under different balance principles in the new power system environment (where the new integrated balance principle adopts mode), and the results are as Figure 12 shown.

[0310] Figure 12 The 4 curves in

[0311] are the correlation growth relationship curves of the new energy penetration rate (abscissa) - new energy curtailment rate (ordinate) obtained by simulation. It can be seen that:

[0312] (1) The new energy curtailment rate increases with the increase of the new energy penetration rate, and the growth processes corresponding to different balance principles are different, that is, different balance principles will shape different new power system balance development paths.

[0313] (2) Under the same new energy penetration rate, the new energy curtailment rate corresponding to the new power balance principle is higher than that of the conventional principle. Since the conventional principle does not control the balance risk and cannot adapt to the new power system balance form with high uncertainty, that is, the objective cost of scientifically controlling the new power system balance risk and ensuring the safe and orderly promotion of the energy transformation is "sacrificing a certain new energy utilization rate".

[0313] (3) Compared with the new basic balance principle, the new integrated balance principle significantly reduces the new energy curtailment rate. For example, when the new energy penetration rate is about 35%, the new energy curtailment rate is reduced by 10 percentage points (halved), with huge benefits; compared with the conventional integrated balance principle, the new integrated balance principle has a slight impact on the new energy utilization rate. For example, when the new energy penetration rate is about 35%, the new energy curtailment rate is only increased by about 0.5 percentage points. That is, the new integrated power balance principle maximally promotes the consumption of new energy at the least cost while ensuring safety.

[0314] As can be seen from the above, the new integrated power balance principle best meets the balance needs of the new power system and is a key choice for the construction and development of the new power system. This application conducts a systematic study on the power balance principle and its engineering mode of the new power system through theoretical derivation and example analysis, and obtains the following conclusions:

[0315] (1) The new power balance principle of the new power system proposed in this application systematically solves the key problems such as the intertwined coupling of "probabilistic" and "integrated" power balance, the mutual influence of "power supply guarantee" and "consumption", and the difficulty in unified quantitative characterization of "balance risk" and "balance target" in the environment of the new power system;

[0316] (2) The proposed solution method for the new integrated power balance equation based on numerical calculation effectively solves the problem of difficult solution of the new integrated power balance equation.

[0317] (3) In the environment of the new power system, the balance mode will gradually transition from the algebraic balance of independent balance areas to the whole network, all elements, and probabilistic balance within the integrated balance panoramic space.

[0318] (4) "Computing power" is an important driving force for the power balance of the new power system, and future balance will be based on "computing power".

[0319] (5) In the process of energy transformation, in order to control risks and ensure safety, it is objectively necessary to "sacrifice a certain new energy utilization rate".

[0320] (6) The new integrated power balance principle is an inevitable requirement and key choice for the construction and development of the new power system.

[0321] (7) The proposed theory and engineering mode are both based on the power balance practice of large power grids and have positive significance for promoting the transformation and development of the power balance mode.

[0322] The basic principle of this application is described above in combination with specific embodiments. However, it should be noted that the advantages, advantages, effects, etc. mentioned in this application are only examples and not limitations. It cannot be considered that these advantages, advantages, effects, etc. are essential for each embodiment of this application. In addition, the above disclosed specific details are only for the purpose of illustration and easy understanding, rather than limitations. The above details do not limit this application to necessarily adopt the above specific details to implement. The above description is provided to enable any person skilled in the art to make or use this application. Various modifications to these aspects are very obvious to those skilled in the art, and the general principles defined herein can be applied to other aspects without departing from the scope of this application. Therefore, this application is not intended to be limited to the aspects shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

[0323] The above are only the preferred embodiments of the present invention creation, and are not intended to limit the present invention creation. Any modifications, equivalent replacements, etc. made within the spirit and principle of the present invention creation shall be included within the protection scope of the present invention creation.

[0324] Although the embodiments of the present invention have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principle and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A new power system power balance principle and engineering model application method, characterized in that: Includes steps: S1. Statistical probability density and probability distribution according to the random characteristic law of the balancing elements in each balancing area; each balancing area independently carries out initial balancing; considers the requirements for the probability distribution of the balancing margin of each balancing area and the entire network, and sets the balancing target; S2, based on the new basic balance principle, in the supply guarantee stage, construct a new basic balance equation with algebraic configuration; S3. Based on the new integrated balance principle, during the supply guarantee phase, the conventional integrated balance equation is randomly transformed, a new integrated balance equation is constructed, and a new integrated balance equation solution method based on numerical calculation is proposed; S4: Based on the new basic balance principle, formulate a new energy consumption strategy for each independent balance area to determine whether there is a large-scale new energy abandonment. If so, jump to step S5, otherwise end; S5. Based on the new integrated balance principle to promote the consumption stage, determine whether to enter the integrated balance to promote consumption stage. If so, enter the new integrated balance to promote new energy consumption engineering mode K°, and then make subsequent judgments, otherwise end.

2. According to claim 1, a new power system power balance principle and engineering model application method is characterized in that: Based on the new integrated balance equation, considering the differences in balance objectives, balance means and balance processes, a new integrated balance engineering model is summarized. The new integrated balance engineering model includes a new integrated balance to ensure power supply engineering model H° and a new integrated balance to promote new energy consumption engineering model K°. The new integrated balance to ensure power supply engineering model H° includes a natural mutual assistance model and collaborative model The new integrated balance-promoting new energy consumption engineering model K° includes the natural mutual assistance model and collaborative model 3. According to claim 1, a new power system power balance principle and engineering model application method is characterized in that: The step S2 specifically includes the following steps: S201: Each balance zone independently sets an initial balance boundary and calculates a risk conversion factor for the independent balance zone Construct new basic equilibrium equations of algebraic configuration; S202, judging whether the balance requirement is met, if yes, jumping to the step S4, otherwise jumping to the step S203; S203, judging whether conventional means in the independent balancing area have been exhausted, if so, jumping to step S204, otherwise adjusting the balancing boundary of the independent balancing area, and then returning to the new basic balancing equation to form a closed loop; S204, determine whether to enable integrated balancing to ensure supply, if so, jump to the step S3, otherwise increase the amount of load management measures, and then return to the new basic balance equation to form a closed loop.

4. The novel power system power balance principle and engineering mode application method according to claim 2 is characterized in that: The step S3 also includes the following steps: considering the probability distribution of the balance margin of each balance area and the whole network under the integrated balance environment, comparing the calculation result of the new integrated balance equation solution method with the set balance target, judging whether the balance requirement is met, if so, jumping to the step S4, otherwise adopting the natural mutual assistance mode under the new integrated balance power supply engineering mode H° and collaborative model Any one of the above can be used to adjust the equilibrium boundary of the relevant equilibrium zone, and then return to the new integrated equilibrium equation to form a closed loop.

5. The novel power system power balance principle and engineering model application method according to claim 2 is characterized in that: The subsequent judgment in step S5 specifically includes the following steps: judging whether the consumption has been promoted to the maximum extent, if so, adjusting the new energy consumption strategy of each balancing area, otherwise adopting the natural mutual assistance mode under the new integrated balancing promotion of new energy consumption engineering mode K° and collaborative model Any one of the methods can be used to adjust the balance boundary of the relevant balance zone, and then return to the new integrated balance to promote new energy consumption engineering mode K° to form a closed loop.

6. The novel power system power balance principle and engineering model application method according to claim 1 is characterized in that: The new basic equilibrium equation is: Where: δ, σ are the upper and lower balance margins respectively; R is the maximum power generation capacity of conventional power sources; α is the peak load coefficient of conventional power sources; T is the planned power of the interconnection line; n and l are the predicted output of new energy and the predicted load size respectively; ρ is the reserve rate reserved according to the safety and stability guidelines of the power system; x is the amount of management measures on the load side; y is the amount of abandoned power of new energy; δ Λ , Λ It represents the balance risk control requirements; n° is the random variable of renewable energy output; Δn° is the deviation of the random variable; is the probability density of the random variable Δn°; Represents the probability density and probability distribution function of Δn°; for is the inverse function of ; in this equation, only the new energy balance factor is introduced as a random variable.

7. The novel power system power balance principle and engineering mode application method according to claim 1 is characterized in that: The novel integrated equilibrium equation is: Where: Δn° is the new energy deviation; δ° is the balance margin before and after mutual aid; Δs° is the mutual aid power; the random characteristics of the lower balance margin σ are not considered, and σ is controlled as an algebraic variable in the balance mode arrangement; reflects the balanced risk; is the risk control sub-equation group of each equilibrium zone; is the risk control equation for the entire network; ΔX° is the balance gap of the entire network, and its physical meaning is that the balance gap of the entire network is less than ΔX Λ The probability is greater than λ Λ ; In this equation, only the new energy balance factor is introduced as a random variable.

8. The novel power system power balance principle and engineering model application method according to claim 1 is characterized in that: The novel integrated equilibrium equation solving method based on numerical calculation is referred to as the S calculation process, which includes three steps: decomposition, calculation, and induction, as follows: (1) Decomposition The random vector Δn° is deconstructed by full-dimensional and full-probability space discrete sampling. After deconstruction, any sample vector Δn ξ It is expressed as: Where: Δn ξ is an N-dimensional vector, U Δn。 represents the complete set of deconstructed samples; is the vector Δn ξ The value of the kth dimension in , Represents the vector Δn ξ In the k-th dimension, the sample subset; through formula (17), an N-dimensional random variable Δn° is decomposed into N-dimensional vector samples; For any sample Δn ξ The probability is: Where: is the probability distribution function of the new energy deviation in the kth equilibrium zone, which is the basic statistical parameter; The unknown variable Δn° is converted into a certain numerical space through equations (17) and (18): (2) Calculation For any sample vector Δn ξ Substituting into equation (10) to carry out the integrated balance calculation of the whole network, Where: New energy is converted from n to n+Δn ξ ;H S It is a natural optimization mutual assistance process, and its complete process is determined by the optimization process determined by equations (21) and (22); The objective function is: Where: is the set whose upper balance margin is less than zero after integrated balancing. for The physical meaning of formula (21) is to minimize the balance gap of the entire network; The constraints are: Where: Equations 1 and 2 are the upper balance margins before and after mutual assistance; Equation 3 represents the impact of mutual assistance power Δs on channel power, where P b0 , P b is the channel power set before and after mutual assistance, N is the mapping matrix from Δs to the channel set; the fourth equation represents the set of power dispatching rules in the mutual assistance process; the first inequality requires reasonable control of Δs, and does not cause a balance gap in the balance area without a gap; the second inequality is the channel limit constraint in the mutual assistance process; By using equation 20-22, we can get the sample Δn ξ Balance margin δ of each balance zone after integrated balance under the boundary ξ , due to Δn ξ With δ ξ If the relationship is a necessary causal relationship, the probability of the two is the same, and the integrated balanced margin δ corresponding to the object sample is obtained ξ Probability: (3) Summary To U Δn。 Carrying out integrated balance calculation for all samples in the , we can get the probability space of the corresponding integrated balance margin set: right The joint probability density function of the equilibrium margin δ° is obtained by integrating and summarizing the sorting: Based on the joint probability density of formula (25), the probability density of the balance margin of any balance zone k can be calculated as: In practice, in addition to the risk control requirements for each balancing area, the overall balance risk of the entire network must also be controlled. Therefore, based on formula (26), the probability distribution of the gap ΔΦ° of the entire network is further obtained. The mathematical relationship between ΔΦ° and δ° is as follows: Where: ΔΦ° is the weighted negative balance margin of all balance zones whose balance margin is less than zero, and its physical meaning is the total balance gap of the entire network.

9. The novel power system power balance principle and engineering mode application method according to claim 1 is characterized in that: After introducing the balancing element load, conventional power supply, tie line planned power, and load management measures, the expression of the upper balancing margin is converted to: δ°=R+T+n-ρl+x+(Δn°+Δl°+ΔR°+ΔT°+Δx°) (29) Where: Δl°, ΔR°, ΔT°, Δx° represent the random deviation of load, conventional power generation capacity, tie line planned power, and load management measures respectively; The integrated balance based on formula (29) is the integrated balance of all factors. Without considering the uncertainty of the tie line, the uncertainty of each balance factor in the balance area can be combined according to the statistical method as follows: Where: ΔΩ° is the comprehensive deviation of each balance element in the area; the probability density p of ΔΩ° is ΔΩ° It can be obtained by convolution of the probability density of the deviation of each balance element in the area, that is: Where: is a convolution calculation process; Substituting equations (29) and (31) into the new integrated balance equation (11), the full-factor integrated balance equation can be constructed; the corresponding balance margin solution process is: Taking into account the uncertainty of the tie line, the tie line deviation ΔT° is further introduced into the formula (30), and the balance margin formula of the single balance zone is expanded to: δ°=R+T+n-ρl+x+ΔΩ°+ΔT° (33) In the formula, ΔT° and ΔΩ° are treated as two independent random variables; after substituting formula (33) into the integrated balance equation (11), the expression of the upper balance margin is: Based on formula (34), p is obtained according to the numerical calculation method of "decomposition-calculation-induction" Δδ。 , the joint probability density is: Where: the sample decomposition range is expanded from Δn° to ΔΩ°×ΔT°; the subscript B represents the number of tie-line channels; the corresponding balance margin solution process is:

10. The novel power system power balance principle and engineering mode application method according to claim 2 is characterized in that: The independent balancing of each independent balancing zone using the new basic balancing equation is called a new independent balancing mode G°. The new independent balancing mode G° and the four new integrated balancing engineering modes Further combination constitutes a new power system power balance mode set, and a new power system power balance panoramic space is constructed based on the new power system power balance mode set, and the new power system power balance mode set includes: Type I: G°; Type II: Type III: Ideal type:

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