A method of analyzing and calculating gaseous products during operation outside a power transformation device

Abstract

The application discloses a method for analyzing and calculating gas products during operation of a power transformation device, and relates to the technical field of electric power.The method comprises the following steps: step 1, determining a target device and a measurement position of the target device; step 2, building a device required for collecting a gas sample based on the target device and the measurement position of the target device; step 3, collecting a gas sample of the target device; step 4, analyzing a target gas component by using a gas chromatograph; and step 5, calculating an emission rate of the target gas product of the target device by using a calculation model.The application aims to solve the problem of calculating the gas emission in the existing gas analysis method, and researches an analysis method for gas emission of a power transformation device during operation.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of electric power, more particularly to a method for analyzing and calculating gas products during operation outside a power transformation device. BACKGROUND

[0002] During the operation of a power transformation device, different gases will be generated and discharged into the atmosphere based on the different working states and structures of the device. Collecting and analyzing the gas products during the operation of the power transformation device can help collect greenhouse gases, evaluate the greenhouse gas emissions during the operation of the device, and analyze the environmental impact level during the operation of the substation, which is conducive to the promotion of the "double carbon" goal. On the other hand, through the collection and analysis of characteristic gases, the operation state of the device can be evaluated to determine whether there are faults such as overheating, partial discharge or gas leakage and the degree of these faults, thereby guiding the development of operation and maintenance work. In order to efficiently and accurately analyze these gas products externally, it is of certain research value to use appropriate measurement and calculation methods to carry out analysis. SUMMARY

[0003] In view of the shortcomings of the existing method, the purpose of the present application is to provide a method for analyzing and calculating gas products during operation outside a power transformation device, which aims to solve the problem of gas emission calculation in the existing gas analysis method and research the analysis method of device gas emission during the operation of a power transformation device.

[0004] In order to achieve the above-mentioned purpose, the present application adopts the following technical solutions:

[0005] A method for analyzing and calculating gas products during operation outside a power transformation device, comprising the following steps:

[0006] Step 1, determining a target device and a measurement position of the target device;

[0007] Step 2, building a device required for gas sample collection based on the target device and the measurement position of the target device;

[0008] Step 3, collecting a gas sample of the target device;

[0009] Step 4, analyzing target gas components using a gas chromatograph;

[0010] Step 5, calculating a target gas product emission rate of the target device using a calculation model.

[0011] Optionally, the device required for gas sample collection is specifically set as follows:

[0012] One end of the first nylon hose is aligned with and fixedly attached to the first hard pipe, and the other end is in communication with the first air inlet valve of the collection pump; one end of the second nylon hose is in communication with the aluminum foil gas collection bag, and the other end is in communication with the second air inlet valve.

[0013] Optionally, the calculation model is built based on two-dimensional gas linear diffusion theory under steady state, and the calculation formula is as follows:

[0014]

[0015] wherein J is the flux of the gas [g / (cm2·s)], D is the diffusion coefficient of the gas (cm2 / s), which is determined by the gas and the environment atmosphere in which the gas is located, is the gas content (g / cm3), is the change rate of the gas content in the X direction.

[0016] Optionally, the gas content decreases linearly in the space X:

[0017]

[0018] After the gas flux is obtained based on the above calculation formula, the gas emission rate and the gas emission amount in a period are calculated according to the following method:

[0019]

[0020] wherein N is the number of boundary surfaces of the device that can emit gas, and S is the area of a boundary surface of the device; and then the time length of the period is multiplied to obtain the gas emission amount in the period.

[0021] Optionally, the step 5 comprises:

[0022] Step 5.1, collecting field parameters;

[0023] Step 5.2, calculating the gas diffusion coefficient;

[0024] Step 5.3, calculating the target gas product emission rate of the target device based on the field parameters and the gas diffusion coefficient.

[0025] Optionally, the field parameters include the gas content, the boundary area and the number of boundary surfaces of the target position of the device, the environmental temperature, and the actual distance between the measurer and the measuring point.

[0026] According to the technical solution, compared with the prior art, the method for analyzing and calculating the gas product during operation outside the power transformation device has the following beneficial effects:

[0027] 1. According to the structure characteristics of the power transformation device, the measuring position of the gas emitted by the power transformation device is determined, which helps to improve the possibility of measuring the gas product during operation and the measurement reliability.

[0028] 2、The application innovatively designs a method for collecting and analyzing gas samples outside the power transformation equipment to evaluate the gas products during the operation of the power transformation equipment, which helps to conveniently analyze the characteristic gas emitted by the power transformation equipment, and is used for evaluating the carbon emission level and the operation state of the equipment during the operation of the equipment.

[0029] 3、The application designs a method for calculating the gas emission rate from the measured gas content value based on the gas diffusion theory, which helps to conveniently analyze the gas production of the power transformation equipment and improves the accuracy of the equipment analysis during the operation. BRIEF DESCRIPTION OF DRAWINGS

[0030] In order to more clearly illustrate the technical solutions in the embodiments of the application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description only constitute a part of the embodiments of the application, and for those skilled in the art, other drawings can be obtained without creative labor based on the provided drawings.

[0031] Figure 1 is a flow chart of the method for analyzing and calculating the gas products during the operation outside the power transformation equipment in the embodiments of the application;

[0032] Figure 2 is a gas collection device designed and assembled in the embodiments of the application;

[0033] Figure 3 is a record of gas collection for a certain dry-type power transformation station in the embodiments of the application;

[0034] Figure 4 is a calculation model diagram of the application. DETAILED DESCRIPTION

[0035] The technical solutions in the embodiments of the application will be described clearly and completely below with reference to the drawings in the embodiments of the application. Obviously, the described embodiments only constitute a part of the embodiments of the application, rather than all the embodiments. Based on the embodiments in the application, all other embodiments obtained by those skilled in the art without creative labor are within the protection scope of the application.

[0036] Referring to Figures 1-3 , the preferred embodiments of the application, a method for analyzing and calculating the gas products during the operation outside the power transformation equipment, comprising:

[0037] Step 1, determining the target equipment and the measurement position;

[0038] Step 2, building the equipment required for collecting the gas samples;

[0039] Step 3, collect the gas sample of the target equipment;

[0040] Step 4, analyze the target gas components by using a gas chromatograph;

[0041] Step 5, calculate the target gas product emission rate of the target equipment.

[0042] In this embodiment, the step 1 specifically comprises:

[0043] Step 1.1, select the target equipment which is desired to be concerned.

[0044] Step 1.2, select the target measurement position of the target equipment.

[0045] Step 1.3, according to the measurement position selected in step 1.2, select the measurer position in combination with the actual equipment layout, and determine the distance between the measurer and the measurement position.

[0046] In this embodiment, in step 1, the target equipment comprises an oil-immersed main transformer, a dry-type transformer or a reactor, a gas-insulated equipment and other equipment; the target measurement position of the target equipment comprises:

[0047] (1) oil-immersed main transformer: the bottom of the breather silica gel tank, close to the shell;

[0048] (2) dry-type transformer or reactor: the middle part of the equipment body, close to the cast epoxy resin;

[0049] (3) gas-insulated equipment: the connection weak part such as the weld, the air inlet and the flange, close to the weak part of the shell.

[0050] (4) other equipment: for sealed transformer equipment, at the connection weak part, the connection part or the air outlet; for open transformer equipment, close to the position of the easily heated polymer material.

[0051] In this embodiment, in step 2, the step 2 specifically comprises:

[0052] Step 2.1, obtain an electrically driven gas collection pump which can continuously suck in gas at positive pressure and is provided with an air inlet valve for connecting other components; one long hard straight pipe and one nylon soft pipe, the length of the hard pipe is 80 cm; one short nylon soft pipe and several aluminum foil gas collection bags.

[0053] Step 2.2, assemble the above components into a gas sample collection device: place the long nylon soft pipe on the hard pipe and fix it by sticking, align one end of the long nylon soft pipe with one end of the hard pipe, and connect the other end of the long nylon soft pipe with one air inlet valve of the collection pump; connect one end of the short nylon soft pipe with the aluminum foil gas collection bag, and connect the other end of the short nylon soft pipe with the other air inlet valve of the collection pump when needed.

[0054] In this embodiment, in step 5, the calculation model used is as shown in the schematic diagram Figure 4 :

[0055] The model is characterized by being built based on two-dimensional gas linear diffusion theory under steady state, and the core calculation formula is:

[0056]

[0057] Wherein, J is the flux of the gas [g / (cm 2 ·s)], D is the diffusion coefficient of the gas (cm 2 / s), which is determined by the gas and the environment atmosphere it is in, C is the gas content (g / cm 3 ), is the rate of change of the gas content in the X direction. The gas content decreases linearly in space X:

[0058]

[0059] After obtaining the gas flux based on the above calculation formula, the gas emission rate and the gas emission amount in the period are calculated according to the following method:

[0060]

[0061] Wherein, N is the number of boundary surfaces of the device that can emit gas, and S is the area of a certain boundary surface of the device (cm 2 ).

[0062] Then multiply the time length of the period to obtain the emission amount of the gas in the period.

[0063] Accordingly, the method includes the following steps:

[0064] Step 5.1, collect the field parameters, including:

[0065] (1) Gas content. It should include the gas content at the target position of the device measured in step 3.3, and the gas content at the measurer position measured in step 3.4. If the content is volume content instead of mass content, conversion is needed:

[0066]

[0067] Wherein, C is the mass content (g / cm 3 ), C is the volume content (ppm), and p is the density of the target gas, which can be obtained from a table.

[0068] (2) The boundary area and the number of boundary surfaces of the target position of the equipment. According to the specific determination of the measured equipment and position, the side area of the dry reactor / voltage device is taken by the epoxy resin pouring; the bottom cross-sectional area of the silicone tank of the oil-immersed respirator is taken; and the joint area is taken at the weak part of the gas insulated equipment.

[0069] (3) The ambient temperature.

[0070] (4) If the hard tube is not vertical in step 3.1, that is, the distance between the measurer and the measurement point is not equal to the length of the hard tube, the actual distance between the measurer and the measurement point needs to be measured or calculated according to the inclination level.

[0071] Step 5.2, calculate the gas diffusion coefficient. In this embodiment, the Fuller-Schettler-Giddings semi-empirical formula is used for calculation:

[0072]

[0073] wherein D AB is the diffusion coefficient of gas A in gas B, and it is considered that the component content and state of gas B are not affected by gas A in the diffusion process, T is the ambient temperature (K), P is the ambient pressure, and the unit is atm (atmosphere, 1 standard atmosphere); M A and M B are the relative molecular mass of A and B, V A and V B are the molar volume (cm 3 / mol) of A and B.

[0074] Step 5.3, calculation. First, according to the data collected in step 5.1, the content change rate of the formula is calculated; then, the gas flux is calculated according to the formula; finally, the body emission rate is calculated according to the formula, and the emission amount of the gas in the period is calculated according to the time length of the period.

[0075] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the difference from other embodiments. The same and similar parts between each embodiment can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the related parts can be referred to the method part.

[0076] The foregoing description of the disclosed embodiments enables a person skilled in the art to make or use the application. Modifications of these embodiments will occur to persons of skill in the art, and, while certain modifications are discussed, it is desired to be protected in accordance with the spirit and scope of the application. Therefore, the application is not limited to the specific embodiments shown and described, but only by the scope of the appended claims, unless otherwise specified.

Claims

1. A method for analyzing and calculating gaseous products during operation outside of power equipment, characterized in that, Includes the following steps: Step 1: Determine the target device and its measurement location; Step 2: Based on the target device and its measurement location, construct the equipment required for gas sample collection; Step 3: Collect gas samples from the target device; Step 4: Analyze the target gas composition using a gas chromatograph; Step 5: Calculate the emission rate of the target gaseous products from the target equipment using a computational model; The computational model is based on the steady-state two-dimensional gas linear diffusion theory, and the calculation formula is as follows: Where J is the gas flux [g / (cm²·s)], and D is the gas diffusion coefficient (cm² / s), which is determined by the gas and its surrounding atmosphere. The gas content (g / cm3) Let X be the rate of change of gas content in the X direction; The gas content decreases linearly within space X: After obtaining the gas flux based on the above formula, the gas emission rate and the gas emission amount within the cycle are calculated using the following method: Where N is the number of boundary surfaces where the equipment may emit gas, and S is the area of ​​a certain boundary surface of the equipment; then multiplying by the time length of the period will give the amount of gas emitted during the period.

2. The method for analyzing and calculating gaseous products during operation outside of power equipment according to claim 1, characterized in that, The specific equipment setup required for gas sample collection is as follows: One end of the first nylon hose is aligned with and fixed to the first rigid tube, and the other end is connected to the first air inlet valve of the collection pump; one end of the second nylon hose is connected to the aluminum foil gas collection bag, and the other end is connected to the second air inlet valve.

3. The method for analyzing and calculating gaseous products during operation outside of power equipment according to claim 1, characterized in that, Step 5 includes: Step 5.1: Collect on-site parameters; Step 5.2, calculate the gas diffusion coefficient; Step 5.3: Calculate the emission rate of the target gas products of the target equipment based on the field parameters and the gas diffusion coefficient.

4. The method for analyzing and calculating gaseous products during operation outside of power equipment according to claim 3, characterized in that, Field parameters include: gas content, boundary area and number of boundary surfaces at the target location of the equipment, ambient temperature, and the actual distance between the measurer and the measurement point.

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