Distribution transformer production carbon footprint typical value calculation method based on uncertain data

Abstract

The invention discloses a distribution transformer production carbon footprint typical value calculation method based on uncertain data, and the method comprises the steps: collecting information: obtaining an investigation report of each manufacturer, and calculating a data quality factor # imgabs0 # of the report of each manufacturer; screening samples: according to the proportion of the total number of the collected reports, taking the reports with the top quality factors in the collected reports as a new sample set; constructing a carbon footprint calculation model, and for each manufacturer in the selected new sample set, calculating the carbon footprint of the manufacturer in the production process by using the data in the report of the manufacturer; and according to the calculated carbon footprint values of all reports in the new sample set, averaging to obtain the typical carbon footprint number of the product. The invention provides a carbon footprint typical value calculation method which can be directly and practically applied by a power grid purchasing department and a power grid material quality supervision department and can be specifically implemented, and the method can be widely applied to power grid material purchasing scoring and green evaluation of the power grid material quality supervision department.

Description

Technical Field

[0001] The present invention belongs to the technical field of green evaluation of electric power material production, and specifically is a typical value calculation method for the production carbon footprint of a distribution transformer based on uncertain data, in particular a typical value calculation method for the production carbon footprint of a 10kV oil-immersed distribution transformer. Background Art

[0002] In the green evaluation of power grid materials, it is necessary to investigate the carbon footprint of the manufacturing process of related power materials. By collecting data on materials, energy consumption, waste treatment, etc. in the production process of different manufacturers of the same model, the carbon footprint of typical materials is calculated to determine the typical carbon emissions in the production process of the equipment, which is used to determine the green evaluation standards and scoring benchmarks. This value is the typical value of carbon footprint. 10kV distribution transformers are common power equipment in power grids and are widely used in factories, mines, rural areas, and communities. Among them, 10kV distribution transformers are mainly divided into two categories: oil-immersed and dry-type. Among them, oil-immersed transformers are more common than dry-type transformers, and the production process is more complicated.

[0003] At present, the carbon footprint calculation of transformers at home and abroad mainly focuses on transformers with voltage levels of 35kV and above, and the carbon footprint calculation of 10kV oil-immersed transformers is rare; the production processes of 35kV transformers and 10kV transformers are very different, and their carbon footprint calculation methods are different; the threshold of 10kV oil-immersed transformers is lower than that of 35kV and above transformers. Therefore, there are many 10kV oil-immersed transformer manufacturers, and the production processes of each manufacturer are also different. When the quality supervision agency evaluates the carbon footprint of a certain type of transformer in the production process, it is necessary to conduct research on many manufacturers and obtain their representative carbon footprint typical values. In the process of research and data collection, the data sources of various manufacturers are different, and the data missing situations are different. The research data obtained are uncertain, which affects the calculation of the typical value of carbon footprint. How to rely on these uncertain research data from different manufacturers to calculate the typical value of carbon footprint of 10kV oil-immersed transformer production, there is no relevant literature. Summary of the invention

[0004] The purpose of the present invention is to overcome the above-mentioned shortcomings of the prior art and provide a method for calculating the typical value of the carbon footprint of distribution transformer production based on uncertain data, which is used in the green evaluation of power grid material procurement scoring and power grid material quality supervision departments.

[0005] The calculation of the typical value of carbon footprint requires first calculating the data quality factor of each report. After calculating the data quality factor of each manufacturer's report, screen out reports with good data quality to form a data set; then calculate the typical value of the carbon footprint produced by the manufacturer for each report in the data set, and the average is the typical value.

[0006] The technical solution of the present invention includes the following steps:

[0007] (1) Collect information: Obtain the research reports of each manufacturer, and calculate the data quality factor of each manufacturer's report :

[0008] (1)

[0009] Among them, is the data source weight, is the data source score; is the manufacturing process integrity weight, is the manufacturing process integrity score; is the credibility weight, is the credibility score;

[0010] (2) Screen samples:

[0011] According to the proportion of the total number of collected reports, select the reports with the top quality factors in the collected reports as the new sample set;

[0012] (3) Construct a carbon footprint calculation model. For the selected new sample set, for each manufacturer, use the data in its report to calculate the carbon footprint in the production process of the manufacturer;

[0013] (4) According to the carbon footprint values of all reports in the new sample set calculated in (3), take the average value to obtain the typical carbon footprint number of the product.

[0014] In step (1) of the present invention, the data source weight, is the data source score; is the manufacturing process integrity weight, is the manufacturing process integrity score; is the credibility weight; These weights can be selected based on experience, and the sum of the weights is 100%, that is .

[0015] The credibility score in step (1) of the present invention takes the value of:

[0016] Suppose a total of N reports are collected, and each report has M filled data items, forming a matrix. Let be the th data item in the th report. Determine the credibility scores of each report according to the following steps;

[0017] A. Determine the item with the smallest coefficient of variation (CV) in the report as follows:

[0018] The mean of the j-th item is

[0019] (2)

[0020] The standard deviation of the j-th item is:

[0021] (3)

[0022] Then define the coefficient of variation of the j-th item in the report

[0023] (4)

[0024] According to Equation (4), calculate the set of coefficients of variation for all M items in the report

[0025]

[0026] Find the item corresponding to the minimum value in the set and denote it as the L-th item;

[0027] B. Determination of the credibility score:

[0028] The credibility score of the report is calculated according to the following formula:

[0029] (5)

[0030] D 1 = max( D ( i , L )) − u L ， i ∈ [ 1 , N ] (6)

[0031] D 2 = u L − min( D ( i , L )) ， i ∈ [ 1 , N ] (7)

[0032] (8).

[0033] The screening samples in step (2) of the present invention are: screened according to the proportion of 10% - 50% of the total number of collected reports.

[0034] The carbon footprint calculation model is constructed in step (3) of the present invention as follows:

[0035] For each manufacturer, calculate the carbon footprint in the production process of the manufacturer using the data in its report as:

[0036] (9)

[0037] Among them, is the carbon footprint in the raw material acquisition stage, is the carbon footprint in the manufacturing stage;

[0038] (10)

[0039] Among them, is the carbon footprint of raw material production, is the carbon footprint during transportation, as follows:

[0040] (11)

[0041] Among them is the consumption of the th kind of raw material, is the carbon footprint factor of the th kind of raw material;

[0042] (12);

[0043] Among them is the consumption of the th kind of raw material; is the average transportation distance (km) of the th kind of raw material, is the carbon footprint factor per unit weight transportation distance under the transportation mode of the th kind of raw material;

[0044] The carbon footprint during the manufacturing process is calculated as follows:

[0045] (13);

[0046] Among them: is the carbon footprint of energy (electricity) use, is the carbon footprint of waste disposal, is the carbon footprint of virgin raw materials replaced by renewable waste, is the carbon sink amount generated by photovoltaic power generation;

[0047] (14)

[0048] In the formula: is the electricity consumption of each process of the distribution transformer, and EF is the carbon emission factor of electricity;

[0049] (15)

[0050] In the formula: m is the number of categories of discharged waste, and n is the number of processes of distribution transformer manufacturing. is the emission weight of the th waste to be disposed, is the average transportation distance (km) of the th waste to be disposed, is the carbon footprint factor per unit weight transportation distance under the transportation mode of the th waste to be disposed.

[0051] (16)

[0052] In the formula: is the emission of the th renewable waste, is the carbon footprint factor of the virgin raw material that can be replaced by the th renewable waste, is the quality correction coefficient of the th renewable waste and recycled material, and this coefficient is less than or equal to 1.

[0053] (17)

[0054] In the formula: is the carbon emission factor of electric energy, —— refers to the net photovoltaic energy amount ( ) in the th production process of 1 unit of product,

[0055] (18)

[0056] In the formula: is the total power consumption in the th production process of 1 unit of product. is the proportion of photovoltaic power in the total power consumption in the

[0057] th production process of 1 unit of product,

[0058] When calculating the typical value of the carbon footprint of a 10kV distribution transformer, it is necessary to conduct research on each manufacturer and collect the research data reports of each manufacturer. These data are uncertain and affect the calculation of the typical value of the carbon footprint. The present invention provides a calculation method for the data quality factor of the research report, and according to the calculation results of the data quality factors of each report, the report set is screened, and the reports with the top data quality factors are taken as the data set; the present invention gives a calculation model for the carbon footprint of a 10kV distribution transformer; a calculation method and steps for the typical value of the production carbon footprint of a 10kV distribution transformer based on uncertain data are given.Compared with the prior art, the beneficial effects of the present invention are as follows: The existing calculation of the carbon footprint of the production of distribution transformers only gives rough calculation principles and calculation formulas, which are difficult to apply in practice and cannot be implemented. In view of the actual application requirements of the material procurement department and the quality supervision department, the present invention takes into account the uncertainty of the research data. For the calculation of the typical value of the carbon footprint of the most widely used 10 kV distribution transformer at present, a calculation method for the typical value of the carbon footprint that can be directly applied and specifically implemented by the power grid procurement department and the power grid material quality supervision department is given, which can be widely used in the evaluation of power grid material procurement scores and the green evaluation of the power grid material quality supervision department. BRIEF DESCRIPTION OF THE DRAWINGS

[0059] Figure 1 is the production process flow chart of the three-dimensional winding oil-immersed transformer;

[0060] Figure 2 is the carbon emission boundary diagram of the oil-immersed transformer production stage. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0061] Embodiment 1

[0062] Figure 1 Shown is the production process flow chart of the mainstream product S20-400 kVA three-dimensional winding oil-immersed transformer of the current 10 kV oil-immersed distribution transformer. When calculating the carbon footprint, it is necessary to first understand the production process of the 10 kV oil-immersed distribution transformer. There are many models of 10 kV oil-immersed transformers, but their production processes are basically the same. The differences are the amount of materials used, the size, and the processing time of each process; in addition, some manufacturers rely on outsourcing for the main components.

[0063] SCREENING OF RESEARCH DATA

[0064] There are many manufacturers of 10 kV distribution transformers. When the quality supervision department conducts research on the production process of 10 kV distribution transformers in the industry, multiple manufacturers can be selected for on-site research and questionnaire research, usually dozens of them. Among these research data, there are on-site research and questionnaire research, and there are cases where some manufacturers fill in carelessly, resulting in incorrect data submitted. There are also some manufacturers who provide incorrect data due to incorrect calculation of the energy consumption decomposition value of each process. Therefore, it is necessary to screen these data to select data with higher reliability. For the calculation of the typical value of the carbon footprint of the 10 kV distribution transformer, a calculation method based on the research data quality factor is proposed here:

[0065] For the research data of a certain manufacturer, determine its data quality factor according to the following rules :

[0066] (1)

[0067] Here is the weight of the data source, and is the score of the data source; is the weight of the manufacturing process integrity, and is the score of the manufacturing process integrity; is the weight of the credibility, and is the score of the credibility; The specific values are as follows:

[0068] Data source (on-site, online survey)

[0069] Due to the low threshold of 10kV distribution transformers, there are a large number of transformer manufacturers in the country. The quality supervision department often selects some manufacturers for on-site research, so the data obtained is highly reliable; for some manufacturers surveyed by questionnaire via email, the data filled in may have large errors. According to the score of the data source based on experience The values taken according to experience are as follows:

[0070] Table 1 Data source score

[0071] Manufacturing process integrity

[0072] For 10kV oil-immersed distribution transformers, according to the manufacturing process integrity, they are roughly divided into 3 categories. Category 1: Most components are produced by themselves. Except for insulating bushings, insulating oil, gas relays, and tap changers, they are basically produced by themselves. Category 2: Some auxiliary components such as the fuel tank are purchased externally; Category 3: Some main components such as the iron core are purchased externally. The scores of the manufacturing process integrity of various manufacturers are as follows:

[0073] Table 2 Manufacturing process integrity score Manufacturing process integrity Score Basically self - manufactured 1 A few auxiliary parts are purchased externally 0.8 Key components are purchased externally 0.5

[0074] Credibility evaluation

[0075] When some manufacturers fill in the research data, they fail to carefully calculate the energy consumption of each process, resulting in inaccurate data filled in. Here, the credibility score of this report is scored and evaluated according to the following method:

[0076] There are many production processes for 10kV distribution transformers. Among them, for some processes, due to the large differences in the technical levels and equipment of each manufacturer, the energy consumption differences are large; but for some processes that are relatively simple, the theoretical energy consumption differences of each manufacturer for this process are small; therefore, after finding the item with the smallest coefficient of variation in the reported data in the present invention, using the data of this item filled in by each manufacturer as the standard, the credibility scores of the reports of each manufacturer are calculated.

[0077] Suppose a total of N reports are collected, and each report has M filled data items, forming a matrix. Let be the -th data item in the -th report. Determine the credibility score according to the following steps.

[0078] A. Determine the item with the smallest coefficient of variation CV (Coefficient of Variation) in each report. The method is as follows:

[0079] The mean of the j-th data item of all reports is

[0080] (2)

[0081] The standard deviation of the j-th item is:

[0082] (3)

[0083] Then define the coefficient of variation of the j-th item

[0084] (4)

[0085] According to formula (4), calculate the set of coefficients of variation of all M items

[0086]

[0087] Find the item corresponding to the minimum value in the set, and let it be the L-th item.

[0088] B. Determination of the credibility score of each report:

[0089] The credibility score of the -th report is calculated according to the following formula:

[0090] (5)

[0091] D 1 = max( D ( i , L )) − u L ， i ∈ [ 1 , N ] (6)

[0092] D 2 = u L − min( D ( i , L )) ， i ∈ [ 1 , N ] (7)

[0093] (8)

[0094] For the reports of each manufacturer, calculate the data quality factor , and calculate the data quality factor according to formula (1) , where the weight of the data source , the weight of the manufacturing process integrity , the weight of credibility are all determined empirically.

[0095] Screen the samples, and select the report samples with the top quality factors as the sample set according to the proportion.

[0096] Carbon footprint calculation model

[0097] According to the "PAS - 2050:2008 Specification for the Assessment of Greenhouse Gas Emissions of Goods and Services throughout the Life Cycle" and the "ISO 14067: General Requirements for Greenhouse Gas Verification and Validation Bodies", taking the oil - immersed transformer as an example, first determine the carbon emission boundary diagram in the production stage of the oil - immersed transformer, as Figure 2 shown.

[0098] The carbon footprint calculation of the 10kV oil - immersed distribution transformer production cycle is as follows:

[0099] (9)

[0100] Among them, is the carbon footprint in the raw material acquisition stage, is the carbon footprint in the manufacturing stage;

[0101] (10)

[0102] Among them, is the carbon footprint of raw material production, is the carbon footprint during transportation, and the definition is as follows:

[0103] (11)

[0104] Among them is the consumption of the th raw material, is the carbon footprint factor of the th raw material;

[0105] (12);

[0106] Among them is the consumption of the th raw material; is the average transportation distance (km) of the th raw material, is the carbon footprint factor per unit weight transportation distance under the transportation mode of the th raw material;

[0107] The carbon footprint during the manufacturing process Calculated as follows:

[0108] (13);

[0109] Where: is the carbon footprint of energy (electricity) use, is the carbon footprint of waste disposal, is the carbon footprint of virgin raw materials replaced by renewable waste, is the carbon sink amount generated by photovoltaic power generation.

[0110] (14)

[0111] In the formula: is the electricity consumption of each process of the distribution transformer, and EF is the carbon emission factor of electricity.

[0112] (15)

[0113] In the formula: m is the number of categories of discharged waste, and n is the number of processes in the manufacture of the distribution transformer. is the th discharge weight of the waste to be disposed of, is the th average transportation distance (km) of the waste to be disposed of, is the th carbon footprint factor per unit weight transportation distance under the transportation mode of the waste to be disposed of.

[0114] (16)

[0115] In the formula: is the th emission amount of renewable waste, is the th carbon footprint factor of the virgin raw materials that can be replaced by the renewable waste, is the th quality correction coefficient between the renewable waste and the recycled material, and this coefficient is less than or equal to 1.

[0116] (17)

[0117] In the formula: is the carbon emission factor of electricity, —— refers to the net photovoltaic energy amount ( ) in the th production process of 1 unit of product,

[0118] (18)

[0119] In the formula: is the total power consumption in the i-th production process of 1 unit of product. is the proportion of photovoltaic power in the total power consumption in the i-th production process of 1 unit of product. refers to the proportion of the photovoltaic power generation used for production by the enterprise in the previous fiscal year in the total photovoltaic power generation.

[0120] For the report sample set selected by calculation, calculate the production carbon footprint corresponding to each report and take the average value.

[0121] Obtain the typical carbon footprint data of the 10kV distribution transformer production.

[0122] Example 2

[0123] The quality supervision agency of a provincial power grid calculates the typical carbon footprint for the production process of the 10kV oil-immersed distribution transformer S20-400kVA. Through on-site and online research, 26 pieces of survey data are obtained, and each report contains 20 pieces of research data.

[0124] (1) Report set screening: First, calculate the quality factor. Here, the weight value takes the empirical value: , , . Then calculate the quality factors of the 26 reports. After calculation, sort them from large to small according to the quality factor, and take the top 10 as the calculation sample set.

[0125] (2) Carbon emission calculation of each manufacturer in the sample set

[0126] Here, taking the calculation of a certain manufacturer as an example, its calculated values are as follows:

[0127] Table 3 Carbon emission accounting table of raw materials for S20-400kVA three-dimensional wound oil-immersed transformer

[0128] Table 4 Carbon emission accounting table of raw material transportation stage for S20-400kVA three-dimensional wound oil-immersed transformer

[0129] Table 5 Carbon emission accounting table of production stage for S20-400kVA three-dimensional wound oil-immersed transformer

[0130] Table 6 Carbon emission accounting table of waste carbon recovery for S20-400kVA three-dimensional wound oil-immersed transformer

[0131] Table 7 Carbon emission accounting table of waste transportation for S20-400kVA three-dimensional wound oil-immersed transformer

[0132] The total carbon footprint accounting for its production process is as follows:

[0133] Table 8 Carbon Footprint Accounting Table of S20-400kVA Three-dimensional Coil Oil-Immersed Transformer (Unit: kgCO 2 e) Carbon emissions of raw materials Carbon emissions from raw material transportation Carbon emissions in the production stage Carbon emissions from waste transportation Carbon emissions from waste recycling Total carbon emissions 5103.811 27.347736 116.4024 0.16068 6.716 5241.006

[0134] Through the carbon footprint calculation model of the oil-immersed transformer, the calculated result of the carbon footprint of the 10kV S20-400kVA oil-immersed transformer in this factory is 5246.683 .

[0135] (3) Typical value calculation

[0136] After separately calculating the 10 selected report sample sets, the carbon footprint values of 10 manufacturers are obtained, and then the average value is calculated as: 5184 , so it can be considered that: for the 10kV oil-immersed transformer of model S20-400kVA in this batch of research, the typical value of the carbon footprint in its production cycle is 5184 .

Claims

1. A method for calculating the typical value of the carbon footprint of distribution transformer production based on uncertain data, characterized in that The following steps are involved: (1) Information collection: Obtain research reports from various manufacturers and calculate the data quality factor of each manufacturer’s report. : （1）； in: is the data source weight, Score the data sources; is the manufacturing process integrity weight, is the manufacturing process integrity score; is the credibility weight, is the credibility score; (2) Screening samples: According to the proportion of the total number of collected reports, the reports with the highest quality factors among the collected reports are selected as the new sample set; (3) Construct a carbon footprint calculation model and, for each manufacturer in the selected new sample set, use the data in its report to calculate the carbon footprint of the manufacturer's production process; (4) Take the average of all reported carbon footprint values ​​in the new sample set calculated according to (3) to obtain the typical carbon footprint number of the product.

2. The method for calculating typical carbon footprint of distribution transformer production based on uncertain data according to claim 1 is characterized in that: In step (1) Data source weight, Score the data sources; is the manufacturing process integrity weight, is the manufacturing process integrity score; are the credibility weights; these weights can be selected based on experience, and the sum of the weights is 100%, that is, .

3. The method for calculating typical carbon footprint of distribution transformer production based on uncertain data according to claim 1 is characterized in that: The credibility score in step (1) The value of is: Suppose a total of N reports are collected, each with M items of filled data, forming a , let For the The report Items of data, follow the steps below to determine the credibility score of each report; A. Determine the item with the smallest coefficient of variation (CV) in the report as follows: The j-th mean for （2）； The standard deviation of the jth term for: （3）； The coefficient of variation of the jth item reported is defined as ; (4)； According to formula (4), the set of coefficients of variation of all M items in the report is calculated: ； Find the item corresponding to the minimum value in the set and set it as the Lth item; B. Determination of credibility score: No. Credibility score of reports Calculate as follows: （5）； （6）； （7）； （8）。 4. The method for calculating typical carbon footprint of distribution transformer production based on uncertain data according to claim 1 is characterized in that The screening samples in step (2) are: 10%-50% of the total number of reports collected.

5. The method for calculating typical carbon footprint of distribution transformer production based on uncertain data according to claim 1, characterized in that: The carbon footprint calculation model constructed in step (3) is as follows: For each of these manufacturers, the carbon footprint of the manufacturer’s production process is calculated using the data in its report: （9）； in, Carbon footprint for the raw material acquisition stage, Carbon footprint for the manufacturing stage; （10）； in, The carbon footprint of raw material production, The carbon footprint during transportation is as follows: （11）； in For the The consumption of raw materials, For the Carbon footprint factor of the raw materials; （12）； in For the The consumption of raw materials; For the Average transportation distance of raw materials (km), For the Carbon footprint factor per unit weight and transportation distance for the transportation mode of the raw materials; Carbon footprint of manufacturing Calculated as follows: （13）； in: The carbon footprint of energy use, The carbon footprint of waste disposal, Carbon footprint of primary raw materials replaced by renewable waste, Carbon sinks generated for photovoltaic power generation; （14）； Where: is the electric energy consumption of each process of the distribution transformer, EF is the carbon emission factor of electric energy; （15）； Where: m is the number of categories of waste discharged, n is the number of distribution transformer manufacturing processes; For the The weight of waste to be disposed of, For the Average transportation distance of waste to be disposed of (km), For the The carbon footprint factor per unit weight and transportation distance of the waste to be disposed of under the transportation mode; （16）； Where: For the Emissions of renewable waste For the Carbon footprint factor of primary raw materials that can be replaced by renewable waste, For the The quality correction factor of renewable waste and recycled materials is less than or equal to 1; （17）； Where: is the carbon emission factor of electricity, ——refers to the first Net photovoltaic energy in the production process ( ), （18）； Where: is the total electricity consumption in the i-th production process for one unit of product; is the proportion of photovoltaic power in the total power consumption in the i-th production process of 1 unit of product, It refers to the proportion of photovoltaic power generation used for production by the enterprise in the previous fiscal year in the total photovoltaic power generation.

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