User side energy storage investment scheme evaluation method for calculating voltage sag treatment

Abstract

The invention discloses a user side energy storage investment scheme evaluation method for calculating voltage sag governance, which belongs to the field of energy storage investment scheme evaluation, and comprises the following steps: calculating a user side energy storage cost coefficient and a user side energy storage income of voltage sag governance, and obtaining an evaluation index of a voltage sag sensitive user and an evaluation index of an energy storage operator; according to the investment scheme, key evaluation indexes are obtained through calculation; and integration is carried out based on a foreground theory, a total foreground value of the investment scheme is obtained, and evaluation of the user-side energy storage investment scheme is completed. According to the method, the energy storage cost and the energy storage benefit considering the voltage sag uncertainty and the electricity price fluctuation are calculated, the user scene of voltage sag treatment can be analyzed in detail, meanwhile, the cost and the benefit of the energy storage system are evaluated and quantified through the foreground theory, a basis is provided for judging the advantages and disadvantages of an investment scheme, and the method is suitable for popularization and application. And the investor can conveniently formulate a more flexible and detailed investment scheme in a targeted and purposeful manner.

Description

Technical Field

[0001] The present invention belongs to the field of energy storage investment scheme evaluation, and in particular relates to a user-side energy storage investment scheme evaluation method for calculating voltage sag management. Background Art

[0002] For voltage sag-sensitive users who use a large number of equipment that is susceptible to voltage sag, such as refrigerators, programmable controllers (PLCs), precision machine tools, robots, DC motors, frequency converters, contactors, high-voltage gas discharge lamps, computers, etc., voltage sags can easily cause huge risks and economic losses to them, affecting the high-quality and efficient development of users and causing complaints from users. Installing energy storage on the user side is not only an effective way to reduce peak loads and fill valleys and improve energy efficiency, but also one of the effective ways to alleviate the impact of voltage sags. However, due to the high cost of energy storage investment, it is very important for investors to accurately evaluate the rationality of energy storage investment and formulate appropriate investment plans. Therefore, it is necessary to accurately and reasonably analyze the cost-effectiveness of energy storage for voltage sag-sensitive users, and clarify investment evaluation indicators to provide a reference for investors to choose investment models.

[0003] Existing cost-benefit analysis of user-side energy storage systems mainly focuses on systems such as photovoltaic storage combination, distributed energy storage, park shared energy storage, electric vehicle + energy storage, etc., and lacks detailed analysis of user scenarios that mainly consider voltage sag management; and the time scale for cost-benefit analysis of user-side energy storage is mainly the entire life cycle of energy storage, lacking detailed evidence; at the same time, the investment evaluation indicators of user-side energy storage are general, and no investment evaluation indicators that are fully suitable for users who are sensitive to voltage sags are proposed, nor can multiple indicators be integrated into one evaluation indicator to provide investors with a final reference. Summary of the invention

[0004] In view of the above-mentioned deficiencies in the prior art, the user-side energy storage investment plan evaluation method for calculating voltage sag management provided by the present invention solves the problem that the investment evaluation of the energy storage system lacks detailed analysis and does not fully meet the investment evaluation indicators of users who are sensitive to voltage sags.

[0005] In order to achieve the above-mentioned invention object, the technical solution adopted by the present invention is: a method for evaluating a user-side energy storage investment plan for calculating voltage sag management, comprising the following steps:

[0006] S1: Calculate the user-side energy storage cost coefficient and user-side energy storage benefits for voltage sag management;

[0007] S2: According to the user-side energy storage cost coefficient and user-side energy storage revenue, and based on the investment plan, the evaluation indicators of voltage sag-sensitive users and the evaluation indicators of energy storage operators are calculated to obtain key evaluation indicators;

[0008] S3: According to the key evaluation indicators, based on the prospect theory, the total prospect value of the investment plan is obtained;

[0009] S4: Complete the evaluation of the user-side energy storage investment plan based on the total prospect value of the investment plan.

[0010] The beneficial effects of the present invention are as follows: the present invention can perform a detailed analysis of user scenarios for voltage sag management by calculating the energy storage cost and energy storage benefit that take into account the uncertainty of voltage sag and the volatility of electricity prices, so as to facilitate investors to formulate more flexible and detailed investment plans based on cost-effectiveness on a smaller time scale; at the same time, the present invention evaluates and quantifies the costs and benefits of the energy storage system through prospect theory, and judges the pros and cons of the investment plan based on the total prospect value of the investment plan, and provides a reference for investors to formulate investment plans based on the evaluation indicators and the total prospect value.

[0011] Further: the user-side energy storage cost coefficient includes the energy storage system design cost coefficient, the energy storage system operation cost coefficient, the energy storage system conversion cost coefficient, the energy storage system transportation and installation cost coefficient, and the energy storage system fault repair cost coefficient;

[0012] The expression of the energy storage system design cost coefficient is as follows:

[0013] C de =C fS +C cd

[0014] Among them, C de is the design cost coefficient of the energy storage system, C fs is the feasibility study cost coefficient, C cd is the design cost coefficient;

[0015] The expression of the energy storage system operation cost coefficient is as follows:

[0016]

[0017] Among them, C co is the energy storage system operation cost coefficient, C ES is the capacity of the energy storage system, P ES is the maximum instantaneous power of the energy storage system, c C is the unit investment cost coefficient of energy storage system capacity, c P is the unit investment cost coefficient of the energy storage system power, r is the base discount rate, and N is the life of the energy storage system;

[0018] The expression of the energy storage system conversion cost coefficient is as follows:

[0019] C op =μC co

[0020] Among them, C op is the energy storage system conversion cost coefficient, and μ is the energy storage system operation cost coefficient.

[0021] The beneficial effect of the above further scheme is: by calculating the user-side energy storage cost coefficient, the impact of voltage sag on the benefits of the user-side energy storage cost coefficient can be accurately analyzed, and investors can better manage the risks associated with voltage sag and reduce the economic losses caused by voltage sag.

[0022] Further: the user-side energy storage benefits include the peak-valley arbitrage benefits of the energy storage system, the demand electricity fee savings benefits of the energy storage system, the voltage sag management benefits of the energy storage system, and the annual subsidy coefficient of the energy storage system;

[0023] The expression of the peak-valley arbitrage profit of the energy storage system is as follows:

[0024]

[0025] Among them, B PVA is the peak-valley arbitrage income of the energy storage system, D is the annual operation days of the energy storage system, and B PVA,l is the peak-to-valley arbitrage income of the energy storage system in the first month, D l is the number of energy storage operation days in the first month, P c (k) is the charging power of the energy storage system grid side in the kth period, R(k) is the time-of-use electricity price in the kth period, and Δt is the period interval;

[0026] The expression of the energy storage system demand electricity fee saving benefit is as follows:

[0027] B RD =12(P before -P after ) D

[0028] Among them, B Rd The savings in electricity demand charges for the energy storage system, P before is the maximum power of the user before the energy storage system is installed, P after is the maximum power of the user after the energy storage system is installed, p D is the demand electricity price of the energy storage system;

[0029] The expression of the voltage sag control benefit of the energy storage system is as follows:

[0030]

[0031] Among them, B VQM,l is the voltage sag management benefit of the energy storage system in the first month, F l is the frequency of voltage sag events in the energy storage system in the first month, F totalis the total frequency of voltage sag events in the energy storage system within one year, B VQM The annual economic loss caused by voltage sag on the user side is is the economic loss of the user's j-th production line in the i-th temporary drop event, B single is the economic loss of a single production line, B direct B is the direct economic loss of a single production line tripping during a voltage drop in an industrial process, indirect is the indirect economic loss of a single production line tripping during a voltage drop in an industrial process, B wl is the economic loss of waste, B sl is the economic loss of downtime, B pl Economic loss for production profit, B rl To restart the economic losses, B el is the economic loss of equipment, B ol for additional economic losses;

[0032] The expression of the annual subsidy coefficient of the energy storage system is as follows:

[0033]

[0034] Among them, S ESS is the annual subsidy coefficient for the energy storage system, e SS is the subsidy coefficient of unit energy storage discharge capacity of the energy storage system, and Δt is the time interval.

[0035] The beneficial effects of the above further scheme are: by calculating the user-side energy storage benefits, it can provide investors with a clear economic evaluation framework, provide a scientific basis for the formulation of investment plans, and enhance the stability of the power system; at the same time, the peak-valley arbitrage benefits of the energy storage system and the voltage sag management benefits of the energy storage system can be adjusted according to actual data, and the uncertainty of voltage sag and the volatility of electricity prices can be taken into account in the investment plan, so that investors can formulate more flexible and detailed investment plans.

[0036] Furthermore: the evaluation indicators of the voltage sag sensitive users include: the total net income of the user over the entire life cycle, the user's initial investment cost coefficient, the user's voltage sag management income and the number of negative income months over the entire life cycle.

[0037] The beneficial effect of the above further scheme is: through the evaluation index of users sensitive to voltage sag, the impact of voltage sag on users can be accurately evaluated, the voltage sag control work can be guided, and economic losses can be reduced.

[0038] Furthermore: the total net income of the user over the entire life cycle is expressed as follows:

[0039]

[0040] Among them, I y1 is the total net income of the user over the entire life cycle invested by the owner, I z1 is the total net income of the user during the entire life cycle of leasing, I h1 is the total net income of the user over the entire life cycle under the contract energy management, T S is the duration of energy storage subsidy, R lease is the annual rental of energy storage under leasing, β Contract is the revenue distribution ratio of the operator side under the contract energy management model, B PVA is the peak-valley arbitrage income of the energy storage system, B VQM B is the annual economic loss caused by the voltage sag problem on the user side of the energy storage system, RD is the electricity cost saving income of the energy storage system, N is the life of the energy storage system, S ESS is the annual subsidy coefficient of the energy storage system, C de is the design cost coefficient of the energy storage system, C u1 is the transportation and installation cost coefficient of the energy storage system, C co is the energy storage system operation cost coefficient, C op is the energy storage system cost coefficient, C mal is the failure maintenance cost coefficient of the energy storage system;

[0041] The expression of the user's initial investment cost coefficient is as follows:

[0042]

[0043] Among them, I y2 I is the initial investment cost coefficient of the user invested by the owner. z2 is the initial investment cost coefficient of the user under leasing, I h2 is the user's initial investment cost coefficient under contract energy management, c C is the unit investment cost coefficient of energy storage system capacity, C ES is the capacity of the energy storage system, c P is the unit investment cost coefficient of the energy storage system power, P ES is the maximum instantaneous power of the energy storage system;

[0044] The expression of the user voltage sag management benefit is as follows:

[0045]

[0046] Among them, I y3 The income from the user voltage sag control invested by the owner, I z3 is the voltage sag management income for users under leasing, I h3 Profits from voltage sag management for users under contract energy management;

[0047] The expression for the number of negative income months in the whole life cycle is as follows:

[0048]

[0049] Among them, I y4 is the number of months with negative returns during the entire life cycle of the owner’s self-investment subsidy period, I z4 is the number of months with negative income in the whole life cycle of the lease, I h4 is the number of months with negative income in the whole life cycle under the contract energy management, N y,l is the net income status of the user invested by the owner in the first month, N z,l is the net income status of the user in the first month under leasing, N h,l is the net income status of the user in the first month under the contract energy management, I y,l is the net income of the user invested by the owner in the first month, I z,l is the net income of the user in the first month under leasing, I h,l is the net income of the user in the first month under the contract energy management, B PVA,l It is the peak-valley arbitrage income of the energy storage system in the first month.

[0050] The beneficial effect of the above further scheme is: by calculating the user's total net income over the entire life cycle, the user's initial investment cost coefficient, the user's voltage sag management income and the number of months with negative income over the entire life cycle, it can help users evaluate the feasibility and plans of different investment plans, making the investment more targeted and effective.

[0051] Furthermore: the evaluation indicators of the energy storage operator include: the total net income of the operator over the entire life cycle, the operator's initial investment cost coefficient and the investment recovery speed.

[0052] The beneficial effect of the above further scheme is that the evaluation indicators of energy storage operators can reflect the benefits of energy storage in various aspects, facilitate the evaluation of benefits between different investment schemes, and make investors' evaluation of investment schemes more flexible and comprehensive.

[0053] Further: The expression of the total net income of the operator over the entire life cycle is as follows:

[0054]

[0055] Among them, I yy1 is the total net income of the operator over the entire life cycle invested by the owner, I yz1 is the total net income of the operator over the entire life cycle under leasing, I yh1 is the total net income of the operator over the entire life cycle under the contract energy management, C de is the design cost coefficient of the energy storage system, C u1 is the transportation and installation cost coefficient of the energy storage system, N is the life of the energy storage system, Cco is the energy storage system operation cost coefficient, C op is the energy storage system cost coefficient, C mal is the energy storage system failure maintenance cost coefficient, C equipment The cost of manufacturing energy storage devices for operators, T S is the duration of energy storage subsidy, S ESS is the annual subsidy coefficient of the energy storage system, R lease is the annual rental of energy storage under leasing, β Contract is the revenue distribution ratio of the operator side under the contract energy management model, C de is the design cost coefficient of the energy storage system, B PVA is the peak-valley arbitrage income of the energy storage system, B VQM B is the annual economic loss caused by the voltage sag problem on the user side of the energy storage system, RD Savings on demand electricity charges for energy storage systems;

[0056] The expression of the operator's initial investment cost coefficient is as follows:

[0057]

[0058] Among them, I yy2 I is the initial investment cost coefficient of the operator invested by the owner. yz2 is the initial investment cost coefficient of the operator under leasing, I yh2 is the initial investment cost coefficient of the operator under the contract energy management, c C is the unit investment cost coefficient of energy storage system capacity, C ES is the capacity of the energy storage system, c P is the unit investment cost coefficient of the energy storage system power, P ES is the maximum instantaneous power of the energy storage system;

[0059] The expression of the investment recovery rate is as follows:

[0060]

[0061] Among them, I yy3 The speed of operator investment recovery under the owner's own investment, I yz3 The speed of operator investment recovery under the owner's own investment, I yh3 is the operator investment recovery rate under the owner’s own investment, and n is the number of years for calculating the investment recovery rate.

[0062] The beneficial effects of the above further scheme are: by calculating the operator's total net income over the entire life cycle, the operator's initial investment cost coefficient and the investment recovery rate, it can help operators accurately evaluate investment benefits, reduce risks, improve the transparency and credibility of investment plans, and provide a scientific basis for the evaluation of investment plans.

[0063] Further: the specific steps of S3 are as follows:

[0064] S301: Calculate the subjective weight of each key evaluation indicator using the analytic hierarchy process according to the key evaluation indicators;

[0065] S302: Calculate the objective weight of each key evaluation indicator using the analytic hierarchy process according to the key evaluation indicators;

[0066] S303: Calculate the combined weight of each key evaluation indicator according to the subjective weight and the objective weight;

[0067] S304: Calculate the prospect value of each key evaluation indicator according to the combined weight of each key evaluation indicator;

[0068] S305: Calculate the total prospect value of the investment plan based on the prospect value of each key evaluation indicator.

[0069] The beneficial effects of the above further scheme are: based on the hierarchical analysis method and prospect theory, the key evaluation indicators of the energy storage system are calculated to obtain the total prospect value, which can provide a reference for the formulation of the voltage sag investment plan and enhance the rationality and predictability of the voltage sag investment plan.

[0070] Further: the expression of the total prospect value is as follows:

[0071]

[0072]

[0073] Among them, V total is the total prospect value, d is the distance between the investment plan and the ideal investment plan, D is the distance between the ideal investment plan and the worst investment plan, and W j is the combined weight of key indicator j, V j is the prospect value of key indicator j, W j,s is the subjective weight of key indicator j, W j,o is the objective weight of key indicator j, I j,a is the normalized actual value of key indicator j, I j,e is the normalized expected value of the key indicator j, and α, γ and τ are constants of the prospect function.

[0074] The beneficial effect of the above further scheme is that the total prospect value is obtained by calculation, which helps to evaluate and manage the voltage sag investment plan and maximize the investment benefit. BRIEF DESCRIPTION OF THE DRAWINGS

[0075] Figure 1The present invention is a flow chart of a method for evaluating user-side energy storage investment plans for voltage sag management. DETAILED DESCRIPTION

[0076] The specific implementation modes of the present invention are described below so that those skilled in the art can understand the present invention. However, it should be clear that the present invention is not limited to the scope of the specific implementation modes. For those of ordinary skill in the art, as long as various changes are within the spirit and scope of the present invention as defined and determined by the attached claims, these changes are obvious, and all inventions and creations utilizing the concept of the present invention are protected.

[0077] like Figure 1 As shown, a method for evaluating a user-side energy storage investment plan for calculating voltage sag management includes the following steps:

[0078] S1: Calculate the user-side energy storage cost coefficient and user-side energy storage benefits for voltage sag management;

[0079] S2: According to the user-side energy storage cost coefficient and user-side energy storage income, and based on the investment plan, the evaluation indicators of voltage sag-sensitive users and the evaluation indicators of energy storage operators are calculated to obtain key evaluation indicators;

[0080] S3: According to the key evaluation indicators, based on the prospect theory, the total prospect value of the investment plan is obtained;

[0081] S4: Complete the evaluation of the user-side energy storage investment plan based on the total prospect value of the investment plan.

[0082] In S1, the user-side energy storage cost coefficient includes the energy storage system design cost coefficient, the energy storage system operation cost coefficient, the energy storage system conversion cost coefficient, the energy storage system transportation and installation cost coefficient, and the energy storage system fault repair cost coefficient; among them,

[0083] The expression of the energy storage system design cost coefficient is as follows:

[0084] C de =C fs +C cd

[0085] Among them, C de is the design cost coefficient of the energy storage system, C fs is the feasibility study cost coefficient, C cd is the design cost coefficient;

[0086] The expression of the energy storage system operation cost coefficient is as follows:

[0087]

[0088] Among them, C cois the energy storage system operation cost coefficient, C ES is the capacity of the energy storage system, P ES is the maximum instantaneous power of the energy storage system, c C is the unit investment cost coefficient of energy storage system capacity, c P is the unit investment cost coefficient of the energy storage system power, r is the base discount rate, and N is the life of the energy storage system;

[0089] The expression of the energy storage system discount cost coefficient is as follows:

[0090] C op =μC co

[0091] Among them, C op is the energy storage system conversion cost coefficient, μ is the energy storage system operation cost coefficient, which is generally between 0.5% and 4.0%.

[0092] The transportation and installation cost coefficient of the energy storage system is C u1 , calculated based on the construction time and labor costs at the location of the energy storage system;

[0093] The energy storage system failure maintenance cost coefficient is C mal , the historical maintenance cost data can be counted and the average value can be taken.

[0094] In S1, the user-side energy storage benefits include the peak-valley arbitrage benefits of the energy storage system, the demand electricity fee savings of the energy storage system, the voltage sag management benefits of the energy storage system, and the annual subsidy coefficient of the energy storage system;

[0095] The expression of peak-valley arbitrage profit of energy storage system is as follows:

[0096]

[0097] Among them, B PVA is the peak-valley arbitrage income of the energy storage system, D is the annual operation days of the energy storage system, and B PVA,l is the peak-to-valley arbitrage income of the energy storage system in the first month, D l is the number of energy storage operation days in the first month, P c (k) is the charging power of the energy storage system in the kth period on the grid side, R(k) is the time-of-use electricity price in the kth period, Δt is the period interval, which can be 1 hour; among them, the electricity price can be divided into three stages in a year: the flood season, the dry season, and the normal water season. The peak and valley electricity prices fluctuate on the basis of the flood and dry seasons, and the fluctuation of electricity prices will affect the peak-valley arbitrage income of the energy storage system, thereby affecting the overall income; therefore, the volatility of electricity prices in each stage needs to be considered when formulating medium- and short-term investment plans.

[0098] The expression of the energy storage system demand electricity charge savings is as follows:

[0099] B RD =12P before -P after ) D

[0100] Among them, B Rd The savings in electricity demand charges for the energy storage system, P before is the maximum power of the user before the energy storage system is installed, P after is the maximum power of the user after the energy storage system is installed, p D is the demand electricity price of the energy storage system;

[0101] The expression of the voltage sag control benefit of the energy storage system is as follows:

[0102]

[0103] Among them, B VQM,l is the voltage sag management benefit of the energy storage system in the first month, F l is the frequency of voltage sag events in the energy storage system in the first month, F total is the total frequency of voltage sag events in the energy storage system within one year, B VQM The annual economic loss caused by voltage sag on the user side is is the economic loss of the user's j-th production line in the i-th temporary drop event, B single is the economic loss of a single production line, B direct B is the direct economic loss of a single production line tripping during a voltage drop in an industrial process, indirect is the indirect economic loss of a single production line tripping during a voltage drop in an industrial process, B wl is the economic loss of waste, B sl is the economic loss of downtime, B pl Economic loss for production profit, B rl To restart the economic losses, B el is the economic loss of equipment, B ol The indirect economic loss caused by a single trip of a single production line during a voltage sag in an industrial process includes hidden costs such as fines or compensation due to increased defective product rates, costs of handling customer complaints, competitiveness, reputation, customer satisfaction, and employee tolerance. At the same time, voltage sags are random and uncertain, and their distribution varies in different months, with more frequent sags during thunderstorm seasons. In practical applications, the parameters in the expression of the voltage sag management benefits of the energy storage system are adjusted based on the distribution of actual voltage sag monitoring data of users.

[0104] The expression of the annual subsidy coefficient of the energy storage system is as follows:

[0105]

[0106] Among them, S ESS is the annual subsidy coefficient for the energy storage system, e SS is the subsidy coefficient for unit energy storage discharge of the energy storage system, Δt is the time interval, and is generally taken as month.

[0107] In S2, the evaluation indicators of voltage sag sensitive users include: total net income of users over their entire life cycle, coefficient of initial investment cost of users, income from voltage sag management of users, and number of months with negative income over their entire life cycle;

[0108] The total net income of the user over the entire life cycle is used to evaluate the total profit of the user's investment;

[0109] The user's initial investment cost coefficient is used to evaluate the user's initial investment pressure. Users may give up investment due to insufficient initial funds or high initial investment pressure;

[0110] The user voltage sag management benefit is used to evaluate the user's willingness to invest in energy storage. The higher the benefit, the higher the user's willingness to invest in energy storage. The smaller the benefit, the lower the user's willingness to invest in energy storage.

[0111] The number of months with negative returns over the entire life cycle is used to evaluate the stability of user returns and the rationality of investment plans.

[0112] In S2, the evaluation indicators of energy storage operators include: the total net income of the operator over the entire life cycle, the operator's initial investment cost coefficient, and the investment recovery speed;

[0113] The total net income of the operator over its entire life cycle is used to evaluate the total profit of the operator's investment;

[0114] The operator's initial investment cost coefficient is used to evaluate the operator's initial investment pressure. When the number of users faced by the operator increases, the initial investment cost will become a key factor affecting whether the operator can expand investment;

[0115] The investment recovery rate is used to evaluate the stability of the operator's investment return and the investment risk.

[0116] In S2, according to the user-side energy storage cost coefficient and the user-side energy storage income, and based on the investment plan, the evaluation index of the voltage sag sensitive user and the evaluation index of the energy storage operator are calculated to obtain the key evaluation index;

[0117] Among them, investment plans include owner-investment, leasing, contract energy management and other plans, which can be designed according to the actual energy storage system; technicians can carry out calculations based on the investment plan, select some evaluation indicators from the evaluation indicators of voltage sag-sensitive users and the evaluation indicators of energy storage operators, use them as key evaluation indicators, and calculate specific data;

[0118] In one embodiment of the present invention, when the investment plan is self-investment by the owner, the expressions of the total net income of the user over the whole life cycle, the user's initial investment cost coefficient, the user's voltage sag control income, the number of negative income months over the whole life cycle, the total net income of the operator over the whole life cycle, the operator's initial investment cost coefficient and the investment recovery speed are as follows:

[0119] I y1 =(B PVA +B VQM +B RD )N+T S S ESS

[0120] -[C de +C u1 +N(C co +C op +C mal )]

[0121] I y2 =C u1 +C de +c C C ES +c P P ES

[0122] I y3 =B VQM

[0123]

[0124]

[0125] I yy1 =C de +C u1 +N(C co +C op +C mal )-C equipment

[0126] I yy2 =C equipment

[0127] I yy3 =[C de +C u1 +n(C co +C op +C mal )] / I yy2

[0128] Among them, I y1is the total net income of the user over the entire life cycle invested by the owner, I y2 I is the initial investment cost coefficient of the user invested by the owner. y3 The income from the user voltage sag control invested by the owner, I y4 N is the number of months with negative income during the entire life cycle of the owner’s self-investment subsidy period. y,l is the net income status of the user invested by the owner in the first month, I y,l is the net income of the user invested by the owner in the first month, I yy1 is the total net income of the operator over the entire life cycle invested by the owner, I yy2 I is the initial investment cost coefficient of the operator invested by the owner. yy3 The operator's investment recovery rate under the owner's self-investment, T S is the duration of energy storage subsidy, S ESS is the annual subsidy coefficient of the energy storage system, R lease is the annual rental of energy storage under leasing, C equipment The cost of manufacturing energy storage devices for operators, C u1 is the transportation and installation cost coefficient of the energy storage system, C mal is the energy storage system failure maintenance cost coefficient, B PVA,l is the peak-to-valley arbitrage income of the energy storage system in the first month, and n is the number of years for calculating the investment recovery rate, which is generally less than T S .

[0129] When the investment plan is leasing, the expressions for the total net income of the user's entire life cycle, the user's initial investment cost coefficient, the user's voltage sag control income, the number of months with negative income in the entire life cycle, the operator's total net income in the entire life cycle, the operator's initial investment cost coefficient, and the investment recovery rate are as follows:

[0130] I z1 =(B PVA +B VQM +B RD )N-(C u1 +NR lease )

[0131] I z2 =C u1 +R lease

[0132] I z3 =B VQM

[0133]

[0134] I z,l =B PVA,l +B VQM,l +B RD / 12-R lease / 12

[0135] I yz1 =T S S ESS +NR lease +C u1 +C de -N(C co +C op +C mal )

[0136] I yz2 =c C C ES +c P P ES -R lease

[0137] I yz3 =[n(S ESS +R lease -C co -C op -C mal )+C u1 +C de ] / I yz2

[0138] Among them, I z1 is the total net income of the user during the entire life cycle of leasing, I z2 is the initial investment cost coefficient of the user under leasing, I z3 is the voltage sag management income for users under leasing, I z4 is the number of months with negative income in the whole life cycle of the lease, N z,l is the net income status of the user in the lth month under leasing, z,l is the net income of the user in the first month under leasing, I yz1 is the total net income of the operator over the entire life cycle under leasing, I yz2 is the initial investment cost coefficient of the operator under leasing, I yz3 The speed of recovery of the operator's investment made by the owner;

[0139] When the investment plan is contract energy management, the expressions for the total net income of the user's entire life cycle, the user's initial investment cost coefficient, the user's voltage sag control income, the number of months with negative income in the entire life cycle, the operator's total net income in the entire life cycle, the operator's initial investment cost coefficient, and the investment recovery rate are as follows:

[0140] I h1 =(1-β Contract )(B PVA +B VQM +B RD )NCu1

[0141] I h2 =C u1

[0142] I h3 =B VQM

[0143]

[0144] I h,l =(1-β Contract )(B PVA,l +B VQM,l +B RD / 12)

[0145] I yh1 =T S S ESS +β Contract (B PVA +B VQM +B RD )N+C u1 -N(C co +C op +C mal )-C de

[0146] I yh2 =c C C ES +c P P ES +C de

[0147] I yh3 =[n(S ESS +β Contract (B PVA +B VQM +B RD )-C co -C op -C mal )+C u1 -C de ] / I yh2

[0148] Among them, I h1 is the total net income of the user over the entire life cycle under the contract energy management, I h2 is the user's initial investment cost coefficient under contract energy management, I h3 is the user voltage sag management income under contract energy management, I h4 is the number of months with negative income in the whole life cycle under the contract energy management, N h,lis the net income status of the user in the first month under the contract energy management, I h,l is the net income of the user in the first month under the contract energy management, I yh1 is the total net income of the operator over the entire life cycle under the contract energy management, I yh2 is the initial investment cost coefficient of the operator under the contract energy management, I yh3 The operator's investment recovery rate under the owner's self-investment, β Contract It is the profit distribution ratio on the operator side under the contract energy management model.

[0149] In S3, the prospect theory is used to integrate the key evaluation indicators to obtain the total prospect value of the investment plan based on the key evaluation indicators and prospect theory. The specific steps are as follows:

[0150] S301: Calculate the subjective weight of each key evaluation indicator using the analytic hierarchy process according to the key evaluation indicators;

[0151] S302: Calculate the objective weight of each key evaluation indicator using the analytic hierarchy process according to the key evaluation indicators;

[0152] S303: Calculate the combined weight of each key evaluation indicator according to the subjective weight and the objective weight;

[0153] S304: Calculate the prospect value of each key evaluation indicator according to the combined weight of each key evaluation indicator;

[0154] S305: According to the prospect value of each key evaluation indicator, the total prospect value of the investment plan is calculated. The expression of the total prospect value is as follows:

[0155]

[0156] Among them, V total is the total prospect value, d is the distance between the investment plan and the ideal investment plan, D is the distance between the ideal investment plan and the worst investment plan, and W j is the combined weight of key indicator j, V j is the prospect value of key indicator j, W j,s is the subjective weight of key indicator j, W j,o is the objective weight of key indicator j, I j,a is the normalized actual value of key indicator j, I j,e is the normalized expected value of the key indicator j, and α, γ and τ are constants of the prospect function.

[0157] S4: Based on the total prospect value of the investment plan, the user-side energy storage investment plan is evaluated. The one with the largest total prospect value represents the best investment. Several different investment plans can be evaluated to obtain the total prospect value of each investment plan. By sorting the total prospect value of each investment plan, the best investment plan is selected.

[0158] The beneficial effects of the present invention are as follows: the present invention can perform a detailed analysis of user scenarios for voltage sag management by calculating the energy storage cost and energy storage benefit that take into account the uncertainty of voltage sag and the volatility of electricity prices, so as to facilitate investors to formulate more flexible and detailed investment plans based on cost-effectiveness on a smaller time scale; at the same time, the present invention evaluates and quantifies the costs and benefits of the energy storage system through prospect theory, and judges the pros and cons of the investment plan based on the total prospect value of the investment plan, and provides a reference for investors to formulate investment plans based on the evaluation indicators and the total prospect value.

Claims

1. A method for evaluating user-side energy storage investment plans for voltage sag management, characterized in that: The following steps are involved: S1: Calculate the user-side energy storage cost coefficient and user-side energy storage benefits for voltage sag management; S2: According to the user-side energy storage cost coefficient and user-side energy storage income, and based on the investment plan, the evaluation indicators of voltage sag-sensitive users and the evaluation indicators of energy storage operators are calculated to obtain key evaluation indicators; S3: According to the key evaluation indicators, based on the prospect theory, the total prospect value of the investment plan is obtained; S4: Complete the evaluation of the user-side energy storage investment plan based on the total prospect value of the investment plan.

2. The method for evaluating user-side energy storage investment schemes for calculating voltage sag management according to claim 1 is characterized in that: The user-side energy storage cost coefficient includes the energy storage system design cost coefficient, the energy storage system operation cost coefficient, the energy storage system conversion cost coefficient, the energy storage system transportation and installation cost coefficient, and the energy storage system fault repair cost coefficient; The expression of the energy storage system design cost coefficient is as follows: C de =C fs +C cd Among them, C de is the design cost coefficient of the energy storage system, C fs is the feasibility study cost coefficient, C cd is the design cost coefficient; The expression of the energy storage system operation cost coefficient is as follows: Among them, C co is the energy storage system operation cost coefficient, C ES is the capacity of the energy storage system, P ES is the maximum instantaneous power of the energy storage system, c C is the unit investment cost coefficient of energy storage system capacity, c P is the unit investment cost coefficient of the energy storage system power, r is the base discount rate, and N is the life of the energy storage system; The expression of the energy storage system conversion cost coefficient is as follows: C op =μC co Among them, C op is the energy storage system conversion cost coefficient, and μ is the energy storage system operation cost coefficient.

3. The method for evaluating user-side energy storage investment schemes for calculating voltage sag management according to claim 1, characterized in that: The user-side energy storage benefits include the peak-valley arbitrage benefits of the energy storage system, the demand electricity fee savings benefits of the energy storage system, the voltage sag management benefits of the energy storage system, and the annual subsidy coefficient of the energy storage system; The expression of the peak-valley arbitrage income of the energy storage system is as follows: Among them, B PVA is the peak-valley arbitrage income of the energy storage system, D is the annual operation days of the energy storage system, and B PVA,l is the peak-to-valley arbitrage income of the energy storage system in the first month, D l is the number of energy storage operation days in the first month, P d (k) is the discharge power of the energy storage system on the grid side in the kth period, P c (k) is the charging power of the energy storage system grid side in the kth period, R(k) is the time-of-use electricity price in the kth period, and Δt is the period interval; The expression of the energy storage system demand electricity fee saving benefit is as follows: B RD =12(P before -P after )p D Among them, B RD The savings in electricity demand charges for the energy storage system, P before is the maximum power of the user before the energy storage system is installed, P after is the maximum power of the user after the energy storage system is installed, p D is the demand electricity price of the energy storage system; The expression of the voltage sag control benefit of the energy storage system is as follows: Among them, B VQM,l is the voltage sag management benefit of the energy storage system in the first month, F l is the frequency of voltage sag events in the energy storage system in the first month, F total is the total frequency of voltage sag events in the energy storage system within one year, B VQM The annual economic loss caused by voltage sag on the user side is is the economic loss of the user's j-th production line in the i-th temporary drop event, B single is the economic loss of a single production line, B direct B is the direct economic loss of a single production line tripping during a voltage drop in an industrial process, indirect is the indirect economic loss of a single production line tripping during a voltage drop in an industrial process, B wl is the economic loss of waste, B sl is the economic loss of downtime, B pl = Economic loss of production profit, B rl To restart the economic losses, B el is the economic loss of equipment, B ol for additional economic losses; The expression of the annual subsidy coefficient of the energy storage system is as follows: Among them, S ESS is the annual subsidy coefficient for the energy storage system, e SS is the subsidy coefficient of unit energy storage discharge capacity of the energy storage system, and Δt is the time interval.

4. The method for evaluating user-side energy storage investment schemes for calculating voltage sag management according to claim 1, characterized in that: The evaluation indicators of voltage sag-sensitive users include: the total net income of the user over the entire life cycle, the user's initial investment cost coefficient, the user's voltage sag management income, and the number of negative income months over the entire life cycle.

5. The method for evaluating user-side energy storage investment schemes for calculating voltage sag management according to claim 4 is characterized in that: The expression of the total net income of the user over the entire life cycle is as follows: Among them, I y1 is the total net income of the user over the entire life cycle invested by the owner, I z1 is the total net income of the user during the entire life cycle of leasing, I h1 is the total net income of the user over the entire life cycle under the contract energy management, T S is the duration of energy storage subsidy, R lease is the annual rental of energy storage under leasing, β Contract is the revenue distribution ratio of the operator side under the contract energy management model, B PVA is the peak-valley arbitrage income of the energy storage system, B VQM B is the annual economic loss caused by the voltage sag problem on the user side of the energy storage system, RD is the electricity cost saving income of the energy storage system, N is the life of the energy storage system, S ESS is the annual subsidy coefficient of the energy storage system, C de is the design cost coefficient of the energy storage system, C u1 is the transportation and installation cost coefficient of the energy storage system, C co is the energy storage system operation cost coefficient, C op is the energy storage system cost coefficient, C mal is the failure maintenance cost coefficient of the energy storage system; The expression of the user's initial investment cost coefficient is as follows: Among them, I y2 I is the initial investment cost coefficient of the user invested by the owner. z2 is the initial investment cost coefficient of the user under leasing, I h2 is the user's initial investment cost coefficient under contract energy management, c C is the unit investment cost coefficient of energy storage system capacity, C ES is the capacity of the energy storage system, c P is the unit investment cost coefficient of the energy storage system power, P ES is the maximum instantaneous power of the energy storage system; The expression of the user voltage sag management benefit is as follows: Among them, I y3 The income from the user voltage sag control invested by the owner, I z3 is the voltage sag management income for users under leasing, I h3 Profits from voltage sag management for users under contract energy management; The expression for the number of negative income months in the whole life cycle is as follows: Among them, I y4 is the number of months with negative returns during the entire life cycle of the owner’s self-investment subsidy period, I z4 is the number of months with negative income in the whole life cycle of the lease, I h4 N is the number of negative income months in the whole life cycle under the contract energy management, y,l is the net income status of the user invested by the owner in the first month, N z,l is the net income status of the user in the first month under leasing, N h,l is the net income status of the user in the first month under the contract energy management, I y,l is the net income of the user invested by the owner in the first month, I z,l is the net income of the user in the first month under leasing, I h,l is the net income of the user in the first month under the contract energy management, B PVA,l It is the peak-valley arbitrage income of the energy storage system in the first month.

6. The method for evaluating user-side energy storage investment schemes for calculating voltage sag management according to claim 1, characterized in that: The evaluation indicators of the energy storage operator include: the total net income of the operator over the entire life cycle, the operator's initial investment cost coefficient and the investment recovery speed.

7. The method for evaluating user-side energy storage investment schemes for calculating voltage sag management according to claim 6, characterized in that: The expression of the total net income of the operator over the entire life cycle is as follows: Among them, I yy1 is the total net income of the operator over the entire life cycle invested by the owner, I yz1 is the total net income of the operator over the entire life cycle under leasing, I yh1 is the total net income of the operator over the entire life cycle under the contract energy management, C de is the design cost coefficient of the energy storage system, C u1 is the transportation and installation cost coefficient of the energy storage system, N is the life of the energy storage system, C co is the energy storage system operation cost coefficient, C op is the energy storage system cost coefficient, C mal is the energy storage system failure maintenance cost coefficient, C equipment The cost of manufacturing energy storage devices for operators, T S is the duration of energy storage subsidy, S ESS is the annual subsidy coefficient of the energy storage system, R lease is the annual rental of energy storage under leasing, β Contract is the revenue distribution ratio of the operator side under the contract energy management model, C de is the design cost coefficient of the energy storage system, B PVA is the peak-valley arbitrage income of the energy storage system, B VQM B is the annual economic loss caused by the voltage sag problem on the user side of the energy storage system, RD Savings on demand electricity charges for energy storage systems; The expression of the operator's initial investment cost coefficient is as follows: Among them, I yy2 I is the initial investment cost coefficient of the operator invested by the owner. yz2 is the initial investment cost coefficient of the operator under leasing, I yh2 is the initial investment cost coefficient of the operator under the contract energy management, c C is the unit investment cost coefficient of energy storage system capacity, C ES is the capacity of the energy storage system, c P is the unit investment cost coefficient of the energy storage system power, P ES is the maximum instantaneous power of the energy storage system; The expression of the investment recovery rate is as follows: Among them, I yy3 The speed of operator investment recovery under the owner's own investment, I yz3 The speed of operator investment recovery under the owner's own investment, I yh3 is the operator investment recovery rate under the owner’s own investment, and n is the number of years for calculating the investment recovery rate.

8. The method for evaluating user-side energy storage investment plans for calculating voltage sag management according to claim 1, characterized in that: The specific steps of S3 are as follows: S301: Calculate the subjective weight of each key evaluation indicator using the analytic hierarchy process according to the key evaluation indicators; S302: Calculate the objective weight of each key evaluation indicator using the analytic hierarchy process according to the key evaluation indicators; S303: Calculate the combined weight of each key evaluation indicator according to the subjective weight and the objective weight; S304: Calculate the prospect value of each key evaluation indicator according to the combined weight of each key evaluation indicator; S305: Calculate the total prospect value of the investment plan based on the prospect value of each key evaluation indicator.

9. The method for evaluating user-side energy storage investment schemes for calculating voltage sag management according to claim 8, characterized in that: The expression of the total prospect value is as follows: Among them, V total is the total prospect value, d is the distance between the investment plan and the ideal investment plan, D is the distance between the ideal investment plan and the worst investment plan, and W j is the combined weight of key indicator j, V j is the prospect value of key indicator j, W j,s is the subjective weight of key indicator j, W j,o is the objective weight of key indicator j, I j,a is the normalized actual value of key indicator j, I j,e is the normalized expected value of the key indicator j, and α, γ and τ are constants of the prospect function.

Images