Methods and systems for analyzing the carbon footprint of distribution networks using flexible distribution area carbon monitoring models

Abstract

This application discloses a method and system for analyzing the carbon footprint of a distribution network based on a flexible distribution substation carbon monitoring model, comprising the following steps: establishing a power source normalized carbon source model, and constructing a substation carbon monitoring and carbon footprint model based on the power source normalized carbon source model; obtaining model parameters in the substation carbon monitoring and carbon footprint model; calculating carbon emission values ​​based on the model parameters and the substation carbon monitoring and carbon footprint model; and generating visualization charts based on the carbon emission values. This application provides a highly versatile and visually appealing carbon emission monitoring solution.

Description

Technical Field

[0001] This application relates to carbon footprint analysis technology, and in particular to a method and system for analyzing the carbon footprint of a distribution network based on a flexible distribution area carbon monitoring model. Background Technology

[0002] In recent years, the construction of new power systems has continued to accelerate, and the issue of energy conservation and carbon reduction in power systems has attracted much attention from academics and experts in engineering applications. The most significant feature of new power systems is the increased proportion of renewable energy generation such as wind power, photovoltaic power, and hydropower. In order to address the unpredictable impact of the intermittent and uncertain output of photovoltaic and wind power on the power grid, new power grids must also be equipped with large-scale battery energy storage stations and pumped storage stations of a certain capacity. At the same time, electric vehicles on the load side can be mobilized to participate in grid operation and control through V2G. Through mechanisms such as extensive collaboration, multi-dimensional participation, and broad cooperation, the safe, stable, and reliable power supply of the new distribution network can be achieved.

[0003] While electricity does not directly produce carbon dioxide during its use, carbon emissions are generated during its conversion. Therefore, allocating carbon reduction responsibility based on "energy consumption sharing" is a widely accepted concept in the power sector. For example, 1 kg of standard coal can generate 3 kWh of electricity and emit 1 kg of carbon dioxide. Thus, if a user consumes 1 kWh of electricity, they must share approximately 333g of carbon reduction responsibility.

[0004] While this algorithm can define the carbon emission responsibility allocation standard for coal-fired power generation, it is not applicable to all power grid structures. Therefore, it is necessary to establish a carbon emission assessment model applicable to wind power and a carbon reduction responsibility quota per unit of electricity (hereinafter referred to as "carbon emission index", unit: kg / kWh, such as 0.333 kg / kWh for coal-fired power).

[0005] It is evident that existing technologies have poor versatility and cannot perform carbon footprint analysis for different power grid structures. Furthermore, current technologies have low visualization capabilities, making it impossible to intuitively observe the distribution of carbon footprints. Summary of the Invention

[0006] This invention aims to address at least one of the technical problems existing in the prior art. To this end, this invention proposes a versatile and intuitively visual method and system for analyzing the carbon footprint of distribution networks based on a flexible distribution area carbon monitoring model.

[0007] On the one hand, embodiments of this application provide a method for analyzing the carbon footprint of a distribution network based on a flexible distribution area carbon monitoring model, including the following steps:

[0008] A normalized carbon source model for power sources is established, and a carbon monitoring and carbon footprint model for power distribution areas is constructed based on the normalized carbon source model.

[0009] Obtain the model parameters from the carbon monitoring and carbon footprint model of the aforementioned area;

[0010] Carbon emission values ​​are calculated based on the model parameters and the carbon monitoring and carbon footprint model of the transformer area.

[0011] Visual charts are generated based on the carbon emission figures.

[0012] On the other hand, embodiments of this application provide a distribution network carbon footprint analysis system based on a flexible distribution substation carbon monitoring model, characterized in that it includes:

[0013] A unit is established to build a normalized carbon source model for power sources, and to construct a carbon monitoring and carbon footprint model for the power distribution area based on the normalized carbon source model.

[0014] The acquisition unit is used to acquire model parameters in the carbon monitoring and carbon footprint model of the substation area;

[0015] The calculation unit is used to calculate carbon emission values ​​based on the model parameters and the carbon monitoring and carbon footprint model of the transformer area;

[0016] The generation unit is used to generate a visualization chart based on the carbon emission data.

[0017] On the other hand, embodiments of this application provide a distribution network carbon footprint analysis system based on a flexible distribution substation carbon monitoring model, characterized in that it includes:

[0018] Memory, used to store programs;

[0019] A processor is used to load the program to execute the method for analyzing the carbon footprint of a distribution network based on a flexible distribution area carbon monitoring model.

[0020] On the other hand, embodiments of this application provide a computer-readable storage medium storing a program, characterized in that, when the program is executed by a processor, it implements the method for analyzing the carbon footprint of a distribution network based on a flexible distribution area carbon monitoring model.

[0021] This application embodiment constructs a power source normalized carbon source model and, based on this model, constructs a carbon monitoring and carbon footprint model for the distribution area. The carbon emission analysis of the distribution area is performed using the constructed carbon monitoring and carbon footprint model, and a visual chart is generated by combining the data structure output by the model. The above method adapts to different power grid structures through the power source normalized carbon source model, adapts to the power grid structure with diverse energy types, and facilitates carbon emission monitoring through visualization. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 This is a schematic diagram of a flexible distribution radio area unified structure model provided in an embodiment of this application;

[0024] Figure 2 This application provides a three-dimensional bar chart for 24-hour carbon emission monitoring of a flexible distribution substation based on uniform load characteristics.

[0025] Figure 3 This application provides a novel weakly hierarchical medium-voltage (35kV / 10kV) distribution network structure.

[0026] Figure 4 This is an impedance equivalent model for a medium-voltage distribution network line segment provided in the embodiments of this application. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions of this application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of this application. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0028] Reference Figure 1 and Figure 2 This application provides a method for analyzing the carbon footprint of a distribution network using a distribution area carbon monitoring model, characterized by the following steps:

[0029] S1. Establish a normalized carbon source model for power sources, and construct a carbon monitoring and carbon footprint model for the power distribution area based on the normalized carbon source model.

[0030] S2. Obtain the model parameters in the carbon monitoring and carbon footprint model of the substation area.

[0031] S3. Calculate carbon emission values ​​based on the model parameters and the carbon monitoring and carbon footprint model of the transformer area.

[0032] S4. Generate a visualization chart based on the carbon emission data.

[0033] The construction process of the power source normalization carbon source model is as follows:

[0034] In the process of generating electricity using primary energy sources such as coal, natural gas, hydropower, wind power, and solar energy, carbon emission statistics should cover all stages of the entire life cycle of the power system, including construction, conversion process, equipment maintenance, and decommissioning and recycling.

[0035] Assume the total carbon emissions from power system construction are B kg; the carbon emissions generated by the primary energy consumed in the power generation process are... C kg / kWh; equipment system maintenance carbon emissions are W kg / year; Expected service life of the power generation system is T Annually; Recycling of decommissioned vehicles will increase carbon emissions. R kg; average annual power generation is P kWh / year; therefore, the total carbon emissions over the entire life cycle of a power system, i.e., the normalized carbon source model for power systems, is:

[0036] Equation (1)

[0037] According to the principle of energy consumption allocation for carbon emission responsibility, the carbon emission responsibility to be allocated by power plants should be reduced by their own energy consumption losses, and the energy output coefficient should be used. k This indicates that the carbon emission index model for power sources can be derived from this.

[0038] Equation (2)

[0039] The flexible distribution transformer area monitoring model is established based on the power source normalized carbon source model. The specific establishment process is as follows:

[0040] like Figure 1 As shown, this invention first proposes a unified structural model for flexible distribution substations, which includes: a distribution transformer T m Electricity load, V2G electric vehicles, distributed wind power, distributed photovoltaic power, battery energy storage stations and pumped storage stations.

[0041] T m It is the load of the distribution radio station area and the common point N. m The port for power exchange in the medium-voltage distribution network, assuming the power source of the distribution network is coal-fired power; T m The power supply of electric vehicle V2G, battery energy storage and pumped storage power station branches is bidirectional; the power supply of distributed photovoltaic and distributed wind power branches is unidirectional output; the power supply of the load end is unidirectional input; given the difference in power flow direction of multiple ports in the flexible distribution substation, the power flowing into the 0.4kV AC bus is selected as "+", and the power flowing out of the bus is selected as "-".

[0042] Suppose that at a certain moment, T m The instantaneous power flowing into the busbar on the low-voltage side is +P G The instantaneous flow of the electrical load out of the busbar is -P. L The instantaneous power of the electric vehicle flowing into the bus is + P EV The instantaneous power of distributed photovoltaic and distributed wind power flowing into the busbar is + P PV and + P W The instantaneous power flowing into the busbar from battery energy storage and pumped storage stations is + P Bat. and + P Wat. Neglecting bus impedance, the instantaneous power balance equation can be obtained:

[0043] Equation (3)

[0044] Suppose a day is divided into 12 time periods, the first... i (Take the time period from 0 to 11) (i.e., " t i-1 ~ t i Between ("), the power curves of each branch are respectively used P G,i P L,i , P EV,i , P PV,i , P W,i , P Bat.,i and P Wat.,i This means that the instantaneous power balance equation for the transformer area is satisfied as follows:

[0045] Equation (4)

[0046] Right now:

[0047]

[0048] The daily work output of each branch road was as follows:

[0049]

[0050]

[0051]

[0052]

[0053]

[0054] Equation (5)

[0055] Assuming the branch output power, its carbon emissions M Cb A negative value indicates the output carbon emission reduction responsibility; when the branch input power is M Cb A positive value indicates a commitment to carbon emission reduction. (This is from a branch road.) i M in each time period Cb Represented as:

[0056] Equation (6)

[0057] In the formula δ x It means x The carbon emission index of the power source [refer to formula (2)], "-" indicates that the direction of carbon emission is opposite to the direction of power flow. x G indicates the grid end; PV indicates the distributed photovoltaic end; W indicates the distributed wind power end; Bat. indicates the energy storage battery end; Wat. indicates the pumped storage end; EV indicates the electric vehicle end.

[0058] Based on equations (6) and (4), a carbon emission balance model for a certain period of time can be obtained:

[0059]

[0060] Equation (7)

[0061] In summary, by uniformly modeling the carbon emissions of a specific transformer substation on a single day, the total carbon emissions from electricity load (or the carbon footprint of the substation) can be represented using a matrix approach:

[0062] Equation (8)

[0063] In the formula M Cb-L,i For the first i Carbon emissions from electrical load during a given time period; W x,i express x Branch Road i Energy consumption for a given time period, refer to formula (4).

[0064] exist Figure 2 In the diagram, the horizontal axis represents the time axis, which is divided into 12 time periods, each lasting 2 hours; the vertical axis represents the branch type, which is divided into seven types: distributed photovoltaic, distributed wind power, energy storage batteries, pumped storage, electric vehicles, power grid, and electricity load; the vertical axis represents electrical power and carbon emissions, with positive power indicating that electricity is being generated at that moment and negative carbon emissions corresponding to that moment, and vice versa.

[0065] The innovation of this graphical method lies in its clear and intuitive display of the time dimension, branch type, output characteristics of each branch, and carbon emissions.

[0066] The models mentioned above are all limited to a 24-hour daily time scale, but the model proposed in this invention is scalable and can be applied to larger time scales such as weeks, months, quarters, and years.

[0067] Equation (5) can be used to calculate the total output of each branch of the flexible distribution transformer area on a certain day. Using the data in Equation (8), the total carbon emissions of each branch on that day can be calculated. Based on this, the output characteristic model and carbon emission model of each branch of the flexible distribution transformer area for a certain week, a certain month, a certain quarter and a certain year can be constructed.

[0068] Traditional power distribution networks exhibit a clear hierarchical structure based on voltage levels, with lower-level grids entirely dependent on higher-level grids for power supply. In new power system distribution networks, distributed generation and energy storage units are widely integrated at the load end, giving distribution substations a degree of autonomous power supply capability and the ability to feed power back to the higher-level grid, thus enhancing the initiative of the distribution network. Against this backdrop, this invention proposes a weakly hierarchical medium-voltage distribution network structure, such as... Figure 3 As shown, it mainly consists of flexible distribution radio area T. m and line segment impedance Z m Composition (m is an integer between 1 and N, where N can be 10, 50, 100, etc., and the specific number can be determined according to the actual application scenario), the former structure is as follows Figure 1 As shown, the latter structure is as follows Figure 4 As shown.

[0069] Figure 3 The medium-voltage distribution network structure shown is an infinitely scalable model of distribution areas, with adjacent distribution areas connected by Z-channels. m The mathematical model for the impedance of the connected line segments is as follows:

[0070] Equation (9)

[0071] In the formula S ma and S mb For line segmentation switches, the value is 1 when the switch is closed and 0 when it is open; ω ω is the angular frequency.

[0072] Assuming nodes N m The voltage is V N,m And ignoring the effects of inductance and capacitance on the line, the energy loss caused by the impedance of the line segment is:

[0073] Equation (10)

[0074] Let's assume that the output of each station is... P Gm If the electrical energy input to the medium-voltage bus is positive and the electrical energy output from the bus is negative, then the bus power balance model is:

[0075] Equation (11)

[0076] Equation (2) establishes a unified carbon emission index based on power source type and power generation characteristics. How should the carbon emission index of a distribution substation be established? Here, we propose an approach to an average carbon emission index, which considers only the output characteristics of power generation units such as the power grid, distributed photovoltaic, and distributed wind power in the flexible distribution substation, without considering the output of energy storage units. The average carbon emission index model for the flexible distribution substation is established as follows:

[0077] Equation (12)

[0078] In the formula For the first m The average carbon emission index of each distribution area, under the constraints of... D G , D PV , D W The corresponding ratio coefficients of the power grid, distributed photovoltaic, and distributed wind power in the annual power supply output of the distribution area.

[0079] In the new distribution network, the self-power supply capability of the distribution area is enhanced, and the output of the distribution area in equation (11) is increased. P Gm Assuming it is the average load power of the transformer area on that day, the total carbon emissions of the transformer area on that day can be obtained as follows:

[0080] Equation (13)

[0081] In the formula: M Cb-Gm,j Refers to the m-th station area j The total carbon emissions per day. From equation (11), the carbon emissions per unit impedance of a line segment on the same day can be expressed as:

[0082] Equation (14)

[0083] The carbon footprint model of the weakly hierarchical medium-voltage distribution network described above is then derived as follows:

[0084] Equation (15)

[0085] In the formula With equation (11) PGm The meaning is the same, but the latter specifies the date. j .

[0086] It is understood that, based on the above model and combined with the visualization method provided in the embodiments of this application, the carbon emission status of regional distribution networks and transformer substations can be visualized. Figure 2 The three-dimensional bar chart showing carbon emission monitoring allows power grid managers or users to obtain accurate carbon emission information, guiding them to implement targeted load energy-saving control and take effective energy consumption suppression measures to achieve energy conservation and carbon reduction in the distribution network.

[0087] If the integrated units described in this application are implemented as software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0088] Note that the above are merely preferred embodiments and the technical principles employed in this application. Those skilled in the art will understand that this application is not limited to the specific embodiments described herein, and various obvious changes, readjustments, and substitutions can be made without departing from the scope of protection of this application. Therefore, although this application has been described in detail through the above embodiments, this application is not limited to the above embodiments, and may include many other equivalent embodiments without departing from the concept of this application, the scope of which is determined by the scope of the appended claims.

Claims

1. A method for analyzing the carbon footprint of a distribution network based on a flexible distribution area carbon monitoring model, characterized in that, Includes the following steps: A normalized carbon source model for power sources is established, and a carbon monitoring and carbon footprint model for power distribution areas is constructed based on the normalized carbon source model; wherein, the normalized carbon source model for power sources includes the total carbon emissions of the power system throughout its entire life cycle; Obtain the model parameters from the carbon monitoring and carbon footprint model of the aforementioned area; Carbon emission values ​​are calculated based on the model parameters and the carbon monitoring and carbon footprint model of the transformer area. Visual charts are generated based on the carbon emission figures; The total carbon emissions from the construction of the power system are B kg, the carbon emissions from the primary energy consumed during power generation are C kg / kWh, the carbon emissions from equipment and system maintenance are W kg / year, the expected service life of the power generation system is T years, and the additional carbon emissions from decommissioning and recycling are R kg, with an average annual power generation of P kWh / year. The sum of these figures represents the total carbon emissions throughout the entire lifecycle of the power system. As a normalized carbon source model for power sources, the calculation formula is as follows: ； Determining the carbon emission index model of a power source based on a normalized carbon source model. for: ； In the formula, k represents the energy consumption output coefficient; Based on the power output characteristics of the power grid, distributed photovoltaic, and distributed wind power in flexible distribution transformer areas, the following average carbon emission index model for distribution transformer areas is established: ； In the formula Let D be the average carbon emission index of the m-th distribution area, and let D be the constraint condition. G D PV D W These represent the proportions of the power grid, distributed photovoltaic power, and distributed wind power in the annual power output of the distribution area, respectively. , and These represent the carbon emission indices corresponding to the grid end, distributed photovoltaic end, and distributed wind power end in the m-th transformer area, respectively. According to the power output of the Taiwan area P Gm The average carbon emission index model for the distribution station area calculates the total carbon emissions of the area on that day as follows: ； In the formula, M Cb-Gm,j This refers to the total carbon emissions of the m-th distribution area on the j-th day; Carbon emissions on the same day based on line segment impedance It can be represented as: ； In the formula, N represents the total number of transformer substations; A carbon monitoring and carbon footprint model for the transformer substation is constructed based on the carbon emissions from the line segment impedance, and is expressed as follows: ; M Cb-L,i This represents the carbon emissions from the electrical load during the i-th time period; This represents the electrical energy input to the power grid bus during the i-th time period; This represents the electrical energy of the photovoltaic input bus during the i-th time period; The computer representing the wind power input bus in the i-th time period; This represents the electrical energy exchanged by the battery storage during the i-th time period; This represents the electrical energy exchanged by the pumped storage system during the i-th time period; This represents the electrical energy exchanged by the electric vehicle in the i-th time period; This indicates the carbon emission index at the energy storage battery end; This indicates the carbon emission index of the pumped storage end; This indicates the carbon emission index of electric vehicles.

2. The method for analyzing the carbon footprint of a distribution network based on a flexible distribution area carbon monitoring model according to claim 1, characterized in that, The process of generating visualization charts based on the carbon emission figures specifically involves: Create a three-dimensional chart with the horizontal axis representing the time axis, which is divided into 12 time periods, each lasting 2 hours; the vertical axis represents the branch type, which is divided into seven types: distributed photovoltaic, distributed wind power, energy storage batteries, pumped storage, electric vehicles, power grid, and electricity load. The vertical axis represents the power output and carbon emissions. A visualization chart is generated based on the carbon emission figures and the 3D chart.

3. The method for analyzing the carbon footprint of a distribution network based on a flexible distribution area carbon monitoring model according to claim 2, characterized in that, It also includes the following steps: Based on the user's configuration instructions, create three-dimensional charts with different time lengths.

4. The method for analyzing the carbon footprint of a distribution network based on a flexible distribution area carbon monitoring model according to claim 3, characterized in that, The process also includes the following steps: visual analysis based on a medium-voltage distribution network carbon footprint model, which is specifically: ； In the formula, The output of the Nth power station on date j, M Cb-GN,j This refers to the total carbon emissions of the Nth distribution area on the jth day. This indicates the carbon emissions of the line segment impedance on date j; This represents the average carbon emission index of the Nth distribution area.

5. The method for analyzing the carbon footprint of a distribution network based on a flexible distribution area carbon monitoring model according to claim 4, characterized in that, In the carbon footprint model of medium-voltage distribution networks, the following medium-voltage distribution network structure is adopted. This structure is an infinitely scalable model for distribution areas, with adjacent distribution areas connected via the medium-voltage distribution network structure Zm. ； In the formula, S ma and S mb This is a line segment switch. The value is 1 when the switch is closed and 0 when it is closed. ω is the angular frequency.

6. A carbon footprint analysis system for distribution networks based on a flexible distribution area carbon monitoring model, characterized in that, include: A unit is established to build a normalized carbon source model for power sources and to construct a carbon monitoring and carbon footprint model for the power distribution area based on the normalized carbon source model. The normalized carbon source model includes the total carbon emissions of the power system throughout its entire life cycle, which includes the construction cycle, conversion process, equipment maintenance process, and decommissioning and recycling process of the power system. The acquisition unit is used to acquire model parameters in the carbon monitoring and carbon footprint model of the substation area; The calculation unit is used to calculate carbon emission values ​​based on the model parameters and the carbon monitoring and carbon footprint model of the transformer area; A generation unit is used to generate visual charts based on the carbon emission figures; The total carbon emissions from the construction of the power system are B kg, the carbon emissions from the primary energy consumed during power generation are C kg / kWh, the carbon emissions from equipment and system maintenance are W kg / year, the expected service life of the power generation system is T years, and the additional carbon emissions from decommissioning and recycling are R kg, with an average annual power generation of P kWh / year. The sum of these figures represents the total carbon emissions throughout the entire lifecycle of the power system. As a normalized carbon source model for power sources, the calculation formula is as follows: ； Determining the carbon emission index model of a power source based on a normalized carbon source model. for: ； In the formula, k represents the energy consumption output coefficient; Based on the power output characteristics of the power grid, distributed photovoltaic, and distributed wind power in flexible distribution transformer areas, the following average carbon emission index model for distribution transformer areas is established: ； In the formula Let D be the average carbon emission index of the m-th distribution area, and let D be the constraint condition. G D PV D W These represent the proportions of the power grid, distributed photovoltaic power, and distributed wind power in the annual power output of the distribution area, respectively. , and These represent the carbon emission indices corresponding to the grid end, distributed photovoltaic end, and distributed wind power end in the m-th transformer area, respectively. According to the power output of the Taiwan area P Gm The average carbon emission index model for the distribution station area calculates the total carbon emissions of the area on that day as follows: ； In the formula, M Cb-Gm,j This refers to the total carbon emissions of the m-th distribution area on the j-th day; Carbon emissions on the same day based on line segment impedance It can be represented as: ； In the formula, N represents the total number of transformer substations; A carbon monitoring and carbon footprint model for the transformer substation is constructed based on the carbon emissions from the line segment impedance, and is expressed as follows: ； M Cb-L,i This represents the carbon emissions from the electrical load during the i-th time period; This represents the electrical energy input to the power grid bus during the i-th time period; This represents the electrical energy of the photovoltaic input bus during the i-th time period; The computer representing the wind power input bus in the i-th time period; This represents the electrical energy exchanged by the battery storage during the i-th time period; This represents the electrical energy exchanged by the pumped storage system during the i-th time period; This represents the electrical energy exchanged by the electric vehicle in the i-th time period; This indicates the carbon emission index at the energy storage battery end; This indicates the carbon emission index of the pumped storage end; This indicates the carbon emission index of electric vehicles.

7. A distribution network carbon footprint analysis system based on a flexible distribution area carbon monitoring model, characterized in that, include: Memory, used to store programs; A processor for loading the program to perform the method as described in any one of claims 1-5.

8. A computer-readable storage medium storing a program, characterized in that, When the program is executed by the processor, it implements the method as described in any one of claims 1-5.

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