A method for optimizing the configuration of power system flexibility resources

Abstract

The present invention discloses a method for optimizing the configuration of flexibility resources in an electric power system, comprising the following steps: first, dividing the flexibility resources into three categories, namely, traditional units, energy storage equipment, and controllable loads, and uniformly setting their flexibility operating conditions; second, calculating the time and full life cycle electricity consumption of various types of flexibility resources participating in flexibility regulation based on the uniform operating conditions; finally, calculating the full life cycle kilowatt-hour cost of various types of flexibility resources under the uniformly set operating conditions, making a horizontal comparison of the economic efficiency of the flexibility resources, and displaying the comparison; the present invention can simply and efficiently calculate the economic efficiency of different types of flexibility resources, thereby providing a reference for power grid companies to formulate flexibility resource optimization configuration plans.

Description

Technical Field

[0001] The present invention belongs to the field of electric power systems, and in particular relates to a method for optimizing the configuration of flexibility resources in an electric power system. Background Art

[0002] In order to achieve the "dual carbon" goal, promoting the construction of renewable energy such as wind power and photovoltaics has become an inevitable trend in the development of future power systems. However, as the proportion of renewable energy in the power structure continues to expand, the impact of its randomness, volatility, intermittency and other output characteristics on the power system will become more and more obvious, and the flexibility issues faced by the power system will become more and more prominent, requiring the configuration of flexible resources to meet the system's growing flexibility needs.

[0003] There are many types of flexibility resources, and the technical characteristics, regulation effects and economic benefits of different flexibility resources are significantly different. At present, the research on flexibility resources is mainly focused on the optimal configuration of flexibility resources, and there are few studies that directly calculate the economic efficiency of various types of flexibility resources. This is because some flexibility resources also undertake basic power generation tasks while performing flexibility regulation. It is difficult to calculate the amount of electricity involved in flexibility regulation to judge its economic efficiency, and it cannot further guide the optimal configuration of flexibility resources in the power system. Summary of the invention

[0004] The present invention provides a method for optimizing the configuration of flexibility resources in an electric power system, compares and ranks the economic performance of different types of flexibility resources per unit capacity, solves the problem that it is difficult to compare the economic performance of different types of flexibility resources in an electric power system, and can further guide the optimal configuration of flexibility resources in an electric power system.

[0005] In order to solve the above technical problems, the present invention provides a technical solution: a method for optimizing the configuration of power system flexibility resources, comprising the following steps:

[0006] S1: Classify the flexibility resources and uniformly set the flexibility operation conditions of each type of flexibility resources;

[0007] S2: Calculate the time for various types of flexibility resources to participate in flexibility regulation based on the unified working conditions, and then obtain the full life cycle power of various types of flexibility resources for flexibility regulation;

[0008] S3: A method for calculating the full-cycle electricity cost of flexibility resources is proposed, and a horizontal comparison of the economic efficiency of various types of flexibility resources is conducted;

[0009] S4: The calculation results of the full electricity cost of various types of flexible resources are displayed in order from small to large.

[0010] Furthermore, in step S1, the flexibility resources are divided into traditional units, energy storage equipment and controllable loads.

[0011] Furthermore, the unified flexible operating conditions of the conventional units, energy storage equipment and controllable loads are set as follows:

[0012] The flexible operating condition of the traditional unit specifically refers to the flexible resource output of the traditional unit rising evenly from 0 to the maximum technical output P in t hours every day. max , and then after t hours by P max Evenly decrease to 0;

[0013] The flexible operation condition of the energy storage device specifically refers to the energy storage device being charged for t hours every day, and the power increases from 0 to the maximum charging power P c.max Considering the charge and discharge efficiency δ, and then discharging for δt hours, the power is the maximum discharge power P f.max Down to 0;

[0014] The controllable load flexibility operating condition specifically refers to the controllable load being reduced by the maximum power P in t hours every day. L.max Down to 0.

[0015] Furthermore, in step S2, the time calculation formula for participating in flexibility adjustment under the unified flexibility operation setting conditions of the traditional units, energy storage equipment and controllable loads is as follows:

[0016] (1) The time t for flexibility adjustment under the unified setting conditions of traditional units is defined as:

[0017] t=(β max -β min )×12 (1)

[0018] Where: β max , β min are the maximum and minimum output coefficients of traditional energy units respectively;

[0019] (2) The time t for the energy storage equipment to participate in flexibility regulation under the uniform setting conditions is defined as the average number of hours per day for the energy storage equipment to charge and discharge energy;

[0020] (3) The time t involved in flexibility regulation under the condition of uniform setting of controllable load is defined as:

[0021] t=E Lc / P Lc.max (2)

[0022] Where: E Lc is the response power of the daily controllable load, P Lc.max It is the maximum daily response load.

[0023] Furthermore, in step S2, the time for the traditional units, energy storage devices and controllable loads to participate in flexibility regulation under the unified flexibility operation setting conditions is calculated, and the full life cycle power of the traditional units, energy storage devices and controllable loads participating in flexibility regulation is calculated, and the calculation formula is defined as:

[0024]

[0025] Where: P is the installed capacity of the corresponding flexibility resource; t represents the time that various types of flexibility resources participate in flexibility adjustment every day under uniformly set working conditions; L represents the service life of such resources; δ represents the charging and discharging efficiency of the energy storage equipment, and the value for other types of resources is 1.

[0026] Furthermore, in the step S3, in the method for calculating the full-cycle electricity cost of the flexibility resource, the full electricity cost of the flexibility resource is defined as:

[0027]

[0028] Where: C sc represents the total construction cost of this type of unit capacity flexibility resource in its entire life cycle, C so represents the total fixed operation and maintenance cost of this type of unit capacity flexibility resource in the entire life cycle, C sv represents the total variable operation and maintenance cost of this type of unit capacity flexibility resource in the entire life cycle, C sf It represents the total fuel cost of this type of unit capacity flexibility resource over its entire life cycle.

[0029] Furthermore, the total construction cost of the unit capacity flexibility resource over the entire life cycle is C sc Defined as:

[0030]

[0031] Where: C c represents the construction cost of this type of unit capacity flexibility resource, a represents the bank's loan interest rate, n represents the loan repayment period, is the formula for equal principal and interest loan, which represents the annual repayment rate; ε represents the discount rate of funds.

[0032] Furthermore, the total fixed operation and maintenance cost C of the unit capacity flexibility resource over the entire life cycle is so Defined as:

[0033]

[0034] Where: C o Indicates the annual fixed operation and maintenance cost per unit capacity of this type of flexible resources.

[0035] Furthermore, the total variable operation and maintenance cost C of the unit capacity flexibility resource in the entire life cycle is sv Defined as:

[0036] C sv =C v E (7)

[0037] Where: C v Indicates the variable operation and maintenance cost per unit capacity of this type of flexible resources.

[0038] Furthermore, the total fuel cost C of the unit capacity flexibility resource over the entire life cycle is sf Defined as:

[0039] C sf =C f γE (8)

[0040] Where: C f It represents the fuel cost per million British thermal units of fuel used; γ is the fuel heat ratio, which represents the calorific value required to produce one kilowatt-hour of electricity.

[0041] The present invention has the advantages that:

[0042] (1) The present invention divides flexibility resources into three categories: traditional units, energy storage equipment, and controllable loads, and uniformly sets their flexible operating conditions. It introduces the full-cycle kilowatt-hour cost theory, proposes a method for calculating the full kilowatt-hour cost of flexibility resources, calculates the kilowatt-hour cost of each flexibility resource participating in flexibility regulation, and compares and ranks them in economic efficiency. It can briefly calculate the time and full life cycle electricity consumption of each type of flexibility resource participating in flexibility regulation, thereby providing a reference for power grid companies to formulate flexibility resource optimization configuration plans.

[0043] (2) The present invention proposes a method for calculating the full-cycle kilowatt-hour cost of flexibility resources based on the full-cycle kilowatt-hour cost theory. This method can calculate the full life cycle kilowatt-hour cost of different types of flexibility resources per unit capacity participating in flexibility regulation, thereby analyzing the economic feasibility of different types of flexibility resources.

[0044] (3) The method proposed in the present invention is simple to operate and has intuitive and clear analysis results. It can better solve the problem that it is difficult to compare the economic efficiency of different types of flexibility resources in the power system, and can further guide the optimal configuration of flexibility resources in the power system, which has certain practical value.

[0045] In order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, preferred embodiments are given below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only illustrate the embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0047] Figure 1 A flow chart of a method for optimizing configuration of flexibility resources in a power system;

[0048] Figure 2 Unified operating conditions for flexible operation of traditional units;

[0049] Figure 3 Unify operating conditions for flexible operation of energy storage equipment;

[0050] Figure 4 Uniform operating conditions for controllable load flexibility;

[0051] Figure 5 The cost per kilowatt-hour of each flexibility resource over its entire life cycle. DETAILED DESCRIPTION

[0052] Embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although certain embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be construed as being limited to the embodiments described herein, which are instead provided for a more thorough and complete understanding of the present invention. It should be understood that the drawings and embodiments of the present invention are only for exemplary purposes and are not intended to limit the scope of protection of the present invention.

[0053] It should be understood that the various steps described in the method embodiments of the present invention may be performed in different orders and / or in parallel. In addition, the method embodiments may include additional steps and / or omit the steps shown. The scope of the present invention is not limited in this respect.

[0054] The term "including" and its variations used herein are open inclusions, i.e., "including but not limited to". The term "based on" means "based at least in part on". The term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one additional embodiment"; the term "some embodiments" means "at least some embodiments". The relevant definitions of other terms will be given in the following description.

[0055] It should be noted that the concepts such as "first" and "second" mentioned in the present invention are only used to distinguish different devices, modules or units, and are not used to limit the order or interdependence of the functions performed by these devices, modules or units.

[0056] See also Figure 1 As shown, a method for optimizing the configuration of power system flexibility resources is disclosed, comprising the following steps:

[0057] Step S1: classify the flexibility resources and uniformly set the flexibility operation conditions of various flexibility resources;

[0058] Step S2: Calculate the time for various types of flexibility resources to participate in flexibility regulation based on the unified working condition, and then obtain the full life cycle power of various types of flexibility resources for flexibility regulation;

[0059] Step S3: a method for calculating the full-cycle electricity cost of flexibility resources is proposed, and a horizontal comparison of the economic efficiency of various types of flexibility resources is conducted;

[0060] Step S4: The calculation results of the full electricity cost of each type of flexibility resource are displayed in order from small to large.

[0061] In the above step S1, the flexibility resources are divided into traditional units, energy storage equipment and controllable loads.

[0062] The unified flexible operating conditions of the conventional units, energy storage equipment and controllable loads are set as follows:

[0063] The flexible operating condition of the traditional unit specifically refers to the flexible resource output of the traditional unit rising evenly from 0 to the maximum technical output P in t hours every day. max , and then after t hours by P max Evenly decrease to 0;

[0064] The flexible operation condition of the energy storage device specifically refers to the energy storage device being charged for t hours every day, and the power increases from 0 to the maximum charging power P c.max Considering the charge and discharge efficiency δ, and then discharging for δt hours, the power is the maximum discharge power P f.max Down to 0;

[0065] The controllable load flexibility operating condition specifically refers to the controllable load being reduced by the maximum power P in t hours every day. L.max Down to 0.

[0066] In the above step S2, the time calculation formula for participating in flexibility adjustment under the unified flexibility operation setting conditions of the traditional units, energy storage equipment and controllable loads is as follows:

[0067] (1) The time t for flexibility adjustment under the unified setting conditions of traditional units is defined as:

[0068] t=(β max -β min )×12 (1)

[0069] Where: β max , β min are the maximum and minimum output coefficients of traditional energy units respectively;

[0070] (2) The time t for the energy storage equipment to participate in flexibility regulation under the uniform setting conditions is defined as the average number of hours per day for the energy storage equipment to charge and discharge energy;

[0071] (3) The time t involved in flexibility regulation under the condition of uniform setting of controllable load is defined as:

[0072] t=E Lc / P Lc.max (2)

[0073] Where: E Lc is the response power of the daily controllable load, P Lc.max It is the maximum daily response load.

[0074] In the above step S2, the time for the traditional units, energy storage equipment and controllable loads to participate in flexibility regulation under the unified flexibility operation setting conditions is calculated, and the full life cycle electricity of the traditional units, energy storage equipment and controllable loads participating in flexibility regulation is calculated. The calculation formula is defined as:

[0075]

[0076] Where: P is the installed capacity of the corresponding flexibility resource; t represents the time that various types of flexibility resources participate in flexibility adjustment every day under uniformly set working conditions; L represents the service life of such resources; δ represents the charging and discharging efficiency of the energy storage equipment (other types of resources take 1).

[0077] In the above step S3, in the method for calculating the full-cycle electricity cost of flexibility resources, the full electricity cost of flexibility resources is defined as:

[0078]

[0079] Where: C sc represents the total construction cost of this type of unit capacity flexibility resource in its entire life cycle, C so represents the total fixed operation and maintenance cost of this type of unit capacity flexibility resource in the entire life cycle, C sv represents the total variable operation and maintenance cost of this type of unit capacity flexibility resource in the entire life cycle, C sf It represents the total fuel cost of this type of unit capacity flexibility resource over its entire life cycle.

[0080] The total construction cost of the unit capacity flexibility resource over the entire life cycle is C sc Defined as:

[0081]

[0082] Where: C c represents the construction cost of this type of unit capacity flexibility resource, a represents the bank's loan interest rate, n represents the loan repayment period, is the formula for equal principal and interest loan, which represents the annual repayment rate; ε represents the discount rate of funds.

[0083] The total fixed operation and maintenance cost of the unit capacity flexibility resource over the entire life cycle is C so Defined as:

[0084]

[0085] Where: C o Indicates the annual fixed operation and maintenance cost per unit capacity of this type of flexible resources.

[0086] The total variable operation and maintenance cost of the unit capacity flexibility resource in the entire life cycle is C sv Defined as:

[0087] C sv =C v E (7)

[0088] Where: C v Indicates the variable operation and maintenance cost per unit capacity of this type of flexible resources.

[0089] The total fuel cost of the unit capacity flexibility resource over the entire life cycle is C sf Defined as:

[0090] C sf =C f γE (8)

[0091] Where: C f It represents the fuel cost per million British thermal units of fuel used; γ is the fuel heat ratio, which represents the calorific value required to produce one kilowatt-hour of electricity.

[0092] The following is an example of this application using a certain region as the application object.

[0093] The seven types of flexibility resources are divided into three categories: traditional units, energy storage equipment and controllable loads, such as Figure 2 , Figure 3 and Figure 4 As shown in the figure, the unified operating conditions of the three types of flexibility resources are as follows:

[0094] Flexible operation of traditional units under unified operating conditions Figure 2 As shown in the figure, it specifically means that the output of the traditional unit increases evenly from 0 to the maximum technical output Pmax in t hours every day, and then increases from P max Decreases to 0 evenly.

[0095] Energy storage equipment flexible operation uniform working conditions such as Figure 3 As shown, it specifically means that the energy storage device is charged for t hours every day, and the power increases from 0 to the maximum charging power P c.max , considering the charge and discharge efficiency δ, and then through δ t hour discharge, the power is determined by the maximum discharge power P f.max Down to 0.

[0096] Controllable load flexibility operation uniform working conditions such as Figure 4 As shown, it specifically means that the controllable load is reduced by the maximum power P in t hours every day. L.max Down to 0.

[0097] The time t that the three types of flexibility resources participate in flexibility regulation under uniformly set working conditions is calculated, and then the full life cycle electricity of the flexibility resources for flexibility regulation is obtained.

[0098] The typical parameters of 7 types of flexibility resources and actual cases of demand-side response are selected to calculate the time and life cycle power of flexibility resources participating in flexibility regulation under unified setting conditions. The data comes from a city's power grid planning report. The maximum and minimum output coefficients of traditional units are shown in Table 1. The maximum charging and discharging time of energy storage batteries and pumped storage is 6h. The response power of controllable load in the demand-side response case is 208MWh, and the maximum response load is 203MW.

[0099] Table 1 Maximum and minimum output coefficients of traditional units

[0100] Flexibility Resources Minimum output coefficient Maximum output coefficient Coal-fired power flexibility transformation 0.4 0.94 New gas 0.3 0.95 New coal-fired power 0.6 0.94 New hydropower 0.4 0.8

[0101] The calculated flexibility resource of each unit capacity participates in flexibility regulation under the uniform setting condition. The time t and the full life cycle electricity E are shown in Table 2:

[0102] Table 2 The time t and the total life cycle electricity E of the flexible resources of each unit capacity under the uniform setting conditions for participating in flexibility regulation

[0103] Flexibility Resources Flexibility adjustment time (h) Life cycle electricity consumption of flexibility regulation (MWh) Thermal power flexibility transformation 6.5 23725 Pumped Storage 6 67069 Energy Storage Batteries 6 19710 New gas 7.8 56940 New coal-fired power 4.1 29930 New hydropower 4.8 7300 Controllable load 1 26280

[0104] The full-cycle cost per kilowatt-hour of various types of flexibility resources is calculated, and the economic feasibility of seven types of flexibility resources is analyzed using data published by the U.S. Renewable Energy Laboratory and others. The construction and operation costs and life parameters, fuel and electricity purchase cost parameters, and economic and efficiency parameters of each flexibility resource are shown in Tables 3, 4, and 5, respectively.

[0105] Table 3 Construction, operation and maintenance costs and life parameters of each flexibility resource

[0106]

[0107] Table 4 Fuel and electricity purchase cost parameters for each flexibility resource

[0108]

[0109]

[0110] Table 5 Economic and efficiency parameters of various types of flexibility resources

[0111] Loan interest rate Pay-off period Discount rate Pumped storage efficiency Energy storage efficiency 0.05 5 0.05 0.75 0.8

[0112] The calculated total construction cost, total fixed operation and maintenance cost, total variable operation and maintenance cost, and total fuel cost of each unit capacity of flexible resources under the unified setting conditions are shown in Table 6.

[0113] Table 6 Total construction cost, total fixed operation and maintenance cost, total variable operation and maintenance cost, and total fuel cost for each unit capacity flexibility resource over the entire life cycle

[0114]

[0115] Substitute the calculated life cycle cost and electricity of each unit capacity of flexible resources into the full kilowatt-hour cost calculation model of flexible resources. The calculation results are as follows: Figure 5 As shown in the figure, the calculation results of the full kilowatt-hour cost of each flexibility resource are from small to large: thermal power flexibility transformation, new hydropower, new gas, pumped storage, 3h energy storage, controllable load, and new coal-fired power.

[0116] The above description of various embodiments tends to emphasize the differences between the various embodiments. The same or similar aspects can be referenced to each other, and for the sake of brevity, they will not be repeated herein.

[0117] Note that the above are only preferred embodiments of the present invention and the technical principles used. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and that various obvious changes, readjustments and substitutions can be made by those skilled in the art without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in more detail through the above embodiments, the present invention is not limited to the above embodiments, and may include more other equivalent embodiments without departing from the concept of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A method for optimizing the configuration of power system flexibility resources, characterized in that: The following steps are involved: S1: Classify the flexibility resources and uniformly set the flexibility operation conditions of each type of flexibility resources; S2: Calculate the time for various types of flexibility resources to participate in flexibility regulation based on the unified working conditions, and then obtain the full life cycle power of various types of flexibility resources for flexibility regulation; S3: A method for calculating the full-cycle electricity cost of flexibility resources is proposed, and a horizontal comparison of the economic efficiency of various types of flexibility resources is conducted; S4: The calculation results of the full kilowatt-hour cost of various types of flexible resources are displayed in order from small to large; In step S1, the flexibility resources are divided into traditional units, energy storage equipment and controllable loads; The unified flexible operating conditions of the conventional units, energy storage equipment and controllable loads are set as follows: The flexible operating condition of the traditional unit specifically refers to the flexible resource output of the traditional unit rising evenly from 0 to the maximum technical output P in t hours every day. max , and then after t hours by P max Evenly decrease to 0; The flexible operation condition of the energy storage device specifically refers to the energy storage device being charged for t hours every day, and the power increases from 0 to the maximum charging power P c.max Considering the charge and discharge efficiency δ, and then discharging for δt hours, the power is the maximum discharge power P f.max Down to 0; The controllable load flexibility operating condition specifically refers to the controllable load being reduced by the maximum power P in t hours every day. L.max Down to 0; In step S2, the time calculation formula for participating in flexibility adjustment under the unified flexibility operation setting conditions of the traditional unit, energy storage equipment and controllable load is as follows: (1) The time t for flexibility adjustment under the unified setting conditions of traditional units is defined as: t＝(β max -β min )×12 (1) Where: β max , β min are the maximum and minimum output coefficients of traditional energy units respectively; (2) The time t for the energy storage equipment to participate in flexibility regulation under the uniform setting conditions is defined as the average number of hours per day for the energy storage equipment to charge and discharge energy; (3) The time t involved in flexibility regulation under the condition of uniform setting of controllable load is defined as: t=E Lc / P Lc.max (2) Where: E Lc is the response power of the daily controllable load, P Lc.max It is the maximum daily response load.

2. A method for optimizing the configuration of power system flexibility resources according to claim 1, characterized in that: In step S2, the time for the traditional units, energy storage devices and controllable loads to participate in flexibility regulation under the unified flexibility operation setting conditions is calculated, and the full life cycle power of the traditional units, energy storage devices and controllable loads participating in flexibility regulation is calculated. The calculation formula is defined as: Where: P is the installed capacity of the corresponding flexibility resource; t represents the time that various types of flexibility resources participate in flexibility adjustment every day under uniformly set working conditions; L represents the service life of such resources; δ represents the charging and discharging efficiency of the energy storage equipment, and the value for other types of resources is 1.

3. The method for optimizing the configuration of power system flexibility resources according to claim 1, characterized in that: In step S3, in the method for calculating the full-cycle electricity cost of flexibility resources, the full electricity cost of flexibility resources is defined as: Where: C sc represents the total construction cost of this type of unit capacity flexibility resource in its entire life cycle, C so represents the total fixed operation and maintenance cost of this type of unit capacity flexibility resource in the entire life cycle, C sv represents the total variable operation and maintenance cost of this type of unit capacity flexibility resource in the entire life cycle, C sf It represents the total fuel cost of this type of unit capacity flexibility resource over its entire life cycle.

4. A method for optimizing the configuration of power system flexibility resources according to claim 3, characterized in that: The total construction cost of the unit capacity flexibility resource over the entire life cycle is C sc Defined as: Where: C c represents the construction cost of this type of unit capacity flexibility resource, a represents the bank's loan interest rate, n represents the loan repayment period, is the formula for equal principal and interest loan, which represents the annual repayment rate; ε represents the discount rate of funds.

5. The method for optimizing the configuration of power system flexibility resources according to claim 3, characterized in that: The total fixed operation and maintenance cost C of the unit capacity flexibility resource over the entire life cycle so Defined as: Where: C o Indicates the annual fixed operation and maintenance cost per unit capacity of this type of flexible resources.

6. The method for optimizing the configuration of power system flexibility resources according to claim 3, characterized in that: The total variable operation and maintenance cost C of the unit capacity flexibility resource in the entire life cycle sv Defined as: C sv =C v E (7) Where: C v Indicates the variable operation and maintenance cost per unit capacity of this type of flexible resources.

7. The method for optimizing the configuration of power system flexibility resources according to claim 3, characterized in that: The total fuel cost of the unit capacity flexibility resource over the entire life cycle is C sf Defined as: C sf =C f γE (8) Where: C f It represents the fuel cost per million British thermal units of fuel used; γ is the fuel heat ratio, which represents the calorific value required to produce one kilowatt-hour of electricity.

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