Ternary mixed insulating oil configuration evaluation device and evaluation method

Abstract

The invention discloses a ternary mixed insulating oil configuration evaluation device and evaluation method, and belongs to the technical field of transformer insulating oil evaluation. The evaluation device comprises a computer, an oil breakdown voltage detection device, an oil dielectric loss detection device, an oil viscosity measurement device, a device for detecting total hydrocarbon gas in oil and a heating device. The ternary mixed oil storage device is connected with each detection device; characterizing an insulating property state quantity through breakdown voltage, and characterizing a dielectric loss state quantity through dielectric loss; the viscosity state quantity is represented through the oil viscosity; the stable state quantity of the current ternary mixed insulating oil is formed through the total hydrocarbon content in the oil after breakdown; obtaining an evaluation coefficient according to the state quantity; according to the method, the interference of human factors is avoided, the evaluation result can reflect the configuration state of the ternary mixed insulating oil more actually, and the problem that the ternary mixed insulating oil prepared in different proportions cannot be comprehensively and systematically evaluated is solved.

Description

Technical Field

[0001] This invention belongs to the field of transformer insulating oil evaluation technology, specifically a ternary mixed insulating oil configuration evaluation device and evaluation method. Background Technology

[0002] Of the more than 17 million transformers in operation in the power grid, mineral oil transformers account for over 90%. Traditional mineral oil transformers have been used in the power grid for over a century. Their mineral oil-paper insulation systems suffer from poor thermal stability, are prone to aging, and have low ignition / explosion temperatures, severely restricting their safe operation and service life. Therefore, finding effective methods to mitigate aging, extend transformer lifespan, and improve operational safety has always been a challenging research area. Mineral oil and ester oils have good miscibility, and mixed insulating oils prepared from mineral oil and ester oils possess the unique advantage of combining the strengths of both. In the past two decades, more than a dozen countries, including the United States, France, Japan, and Poland, have conducted extensive research on the formulation and performance of binary mixed insulating oils made from mineral oil and ester oils, achieving many valuable results. However, the dielectric loss and kinematic viscosity of various binary mixed insulating oils prepared by different countries are still relatively high, failing to meet the requirements of the current standard IEC60296-2012. Ternary mixed insulating oils (mineral oil, soybean oil, and modified natural esters) significantly delay the thermal aging of oil-paper insulation and improve the power frequency breakdown and surface flashover performance of the liquid-solid oil-paper system. However, research on the optimal performance ratio is currently lacking. Therefore, a ternary mixed insulating oil preparation device and evaluation method are urgently needed to assess the condition of mixed insulating oils with different ratios, thereby selecting an optimal ratio of ternary mixed insulating oil. Summary of the Invention

[0003] This invention overcomes the shortcomings of the prior art and proposes a ternary mixed insulating oil configuration evaluation device and evaluation method; solving the problem of being unable to conduct a comprehensive and systematic evaluation of ternary mixed insulating oils with different proportions.

[0004] This invention is achieved through the following technical solution: A ternary mixed insulating oil configuration evaluation device includes a mineral oil storage device, a soybean oil storage device, a PFAE oil storage device, and a ternary mixed oil storage device. The mineral oil storage device, soybean oil storage device, and PFAE oil storage device are each connected to the ternary mixed oil storage device via a first pipeline. The device also includes a computer, an oil breakdown voltage detection device, an oil dielectric loss detection device, an oil viscosity measurement device, an oil total hydrocarbon gas detection device, and a heating device. The oil breakdown voltage detection device, oil dielectric loss detection device, oil viscosity measurement device, and heating device are each connected to the ternary mixed oil storage device via a second pipeline. The system is connected in phases, with the total hydrocarbon gas detection device in the oil connected to the heating device and the oil breakdown voltage detection device, respectively. The computer is connected to the oil breakdown voltage detection device, the oil dielectric loss detection device, the oil viscosity measurement device, and the total hydrocarbon gas detection device in the oil via a controller. This allows the computer to acquire the breakdown voltage, dielectric loss, and viscosity of the current ternary mixed insulating oil in the storage device, collected by the oil breakdown voltage detection device, the oil dielectric loss detection device, and the oil viscosity measurement device. It also acquires the total hydrocarbon gas content data collected by the oil breakdown voltage detection device, which is used for the evaluation of the current ternary mixed insulating oil.

[0005] Furthermore, a first valve is installed on the first pipeline, and the computer is connected to the first valve via a controller.

[0006] Furthermore, the ternary mixed oil storage device is equipped with an agitator impeller, and the computer is connected to the motor of the agitator impeller via a controller.

[0007] Furthermore, a second valve is installed on the second pipeline; the computer is connected to the second valve via a controller.

[0008] Furthermore, the computer is connected to the heating device via a controller.

[0009] A method for evaluating the configuration of ternary mixed insulating oil, employing the aforementioned ternary mixed insulating oil configuration evaluation device, includes the following steps: Step 1: According to the current configuration ratio, control the corresponding crude oil in the mineral oil storage device, soybean oil storage device, and PFAE oil storage device to enter the ternary mixed oil storage device to obtain the current ternary mixed insulating oil. Start the oil breakdown voltage detection device, oil dielectric loss detection device, oil viscosity measurement device, and oil total hydrocarbon gas detection device to record the breakdown voltage, dielectric loss, viscosity, and total hydrocarbon gas content of the current ternary mixed insulating oil in the ternary mixed oil storage device. Step 2: Record the breakdown voltage m of the current ternary mixed insulating oil to form the state quantity A representing the insulation performance of the current ternary mixed insulating oil; record the dielectric loss n of the current ternary mixed insulating oil to form the state quantity B representing the dielectric loss of the current ternary mixed insulating oil; record the viscosity x of the current ternary mixed insulating oil to form the viscosity state quantity C; record the total hydrocarbon content y in the oil after breakdown and the total hydrocarbon content k in the oil after heating to form the stability state quantity D of the current ternary mixed insulating oil. Step 3: Based on the current insulation performance state quantity A, dielectric loss state quantity B, and viscosity state quantity C of the ternary mixed insulating oil, compare the current evaluation coefficient U of the ternary mixed insulating oil with each threshold range, and determine the final state of the current ternary mixed insulating oil based on the comparison results.

[0010] Furthermore, the formula for calculating the evaluation coefficient U is as follows: ;

[0011] The evaluation coefficient U of the current ternary mixed insulating oil is compared with each threshold range. Based on the comparison results, the final state of the current ternary mixed insulating oil is determined. When U < 10, the final state of the current ternary mixed insulating oil is poor; when 10 ≤ U < 20, the final state of the current ternary mixed insulating oil is medium; when 20 ≤ U < 30, the final state of the current ternary mixed insulating oil is good; and when 30 ≤ U, the final state of the current ternary mixed insulating oil is excellent.

[0012] Furthermore, according to Formula 1, the insulating performance state quantity A of the current ternary mixed insulating oil is formed; according to Formula 2, the dielectric loss state quantity B of the current ternary mixed insulating oil is formed; according to Formula 3, the viscosity state quantity C of the current ternary mixed insulating oil is formed; and according to Formula 4, the stability state quantity D of the current ternary mixed insulating oil is formed. ; ; ; .

[0013] Furthermore, in step one, the flow rate of oil from the mineral oil storage device, soybean oil storage device, and PFAE oil storage device is controlled by computer, and different proportions of ternary mixed insulating oil are configured in the ternary mixed oil storage device; the heating device is started, and the temperature is raised to 100~110℃ and maintained for 1~1.5h; the total hydrocarbon gas content in the oil breakdown voltage detection device is detected.

[0014] Furthermore, in step one, the ternary mixed insulating oil in the ternary mixed oil storage device is kept in a stirring state, and the ternary mixed insulating oil of each configuration ratio is stirred for 30~50 minutes and then left to stand for 10~15 minutes.

[0015] The beneficial effects of this invention compared to the prior art are as follows: This invention utilizes a computer and controller to regulate the on / off state and status of three types of oil storage devices, enabling automatic real-time configuration of insulating oil. During the configuration process, under the control of the computer and controller, the breakdown voltage, dielectric loss, viscosity, and total hydrocarbon gas content of the mixed oil are detected using an oil breakdown voltage detection device, an oil dielectric loss detection device, an oil viscosity measurement device, and an oil total hydrocarbon gas detection device. This device facilitates the configuration and parameter determination of ternary mixed insulating oil, providing support for subsequent evaluation.

[0016] This invention characterizes the insulation performance state quantity through breakdown voltage, the dielectric loss state quantity through dielectric loss, and the viscosity state quantity through oil viscosity. It also establishes the stable state quantity of the current ternary hybrid insulating oil by analyzing the total hydrocarbon content in the oil after breakdown and the total hydrocarbon content in the oil after heating. Based on these state quantities, evaluation coefficients are derived, thereby achieving a fully scientific ternary hybrid insulating oil state evaluation system. The evaluation method of this invention employs scientific and standardized evaluation methods, avoiding interference from human factors. The evaluation results can more realistically reflect the configuration state of the ternary hybrid insulating oil, solving the problem of not being able to conduct a comprehensive and systematic evaluation of ternary hybrid insulating oils with different proportions. Attached Figure Description

[0017] Figure 1 A schematic diagram of the ternary catalytic converter for oil preparation and evaluation. Figure 2 Flowchart for the preparation and evaluation of ternary catalytic converter oils; In the diagram: 1 is a mineral oil storage device, 2 is a soybean oil storage device, 3 is a PFAE oil storage device, 4 is the first pipeline, 5 is a computer, 6 is a ternary mixed oil storage device, 7 is an oil breakdown voltage detection device, 8 is an oil dielectric loss detection device, 9 is an oil viscosity measurement device, 10 is an oil total hydrocarbon gas detection device, 11 is a heating device, 12 is the first valve, 13 is an impeller, 14 is the second valve, and 15 is the second pipeline. Detailed Implementation

[0018] To make the technical problems to be solved, the technical solutions, and the beneficial effects of this invention clearer, the invention will be further described in detail with reference to the embodiments and accompanying drawings. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention. The technical solutions of this invention are described in detail below with reference to the embodiments and accompanying drawings, but the scope of protection is not limited thereto.

[0019] See Figure 1 This embodiment proposes a ternary mixed insulating oil preparation device, including a mineral oil storage device 1, a soybean oil storage device 2, a PFAE oil storage device 3, a first pipeline 4, a computer 5, a ternary mixed oil storage device 6, an oil breakdown voltage detection device 7, an oil dielectric loss detection device 8, an oil viscosity measuring device 9, an oil total hydrocarbon gas detection device 10, a heating device 11, a first valve 12, a stirring impeller 13, a second valve 14, and a second pipeline 15.

[0020] In this embodiment, the mineral oil storage device 1, soybean oil storage device 2, PFAE oil storage device 3, and ternary mixed oil storage device 6 are all existing oil tank structures. The oil breakdown voltage detection device 7 is a ZIJJ-II transformer oil insulating oil dielectric strength tester from Wuhan Kaidi Zhengda Electric Co., Ltd.; the oil dielectric loss detection device 8 is a UHV-640 insulating oil dielectric loss and volume resistivity tester; the oil viscosity measurement device 9 is a LAUDA fully automatic kinematic viscosity analyzer; the oil total hydrocarbon gas detection device 10 is a VOC-8000 total hydrocarbon analyzer; and the heating device 11 is an electric heating device.

[0021] Mineral oil storage device 1, soybean oil storage device 2, and PFAE oil storage device 3 are each connected to ternary mixed oil storage device 6 via first pipelines 4. Each first pipeline 4 is equipped with a first valve 12. A computer 5 is connected to the first valve 12 via a controller, which controls the opening and closing degree and on / off time of the first valve 12, thereby enabling the preparation of ternary mixed insulating oils in different proportions. The ternary mixed oil storage device 6 is equipped with a stirring impeller 13, which facilitates rapid mixing of the insulating oil within the device. The computer 5 is connected to the motor of the stirring impeller 13 via a controller, and controls the stirring speed of the impeller 13.

[0022] The oil breakdown voltage detection device 7, oil dielectric loss detection device 8, oil viscosity measuring device 9, and heating device 11 are connected to the ternary mixed oil storage device 6 via a second pipeline 15, on which a second valve 14 is installed. The oil total hydrocarbon gas detection device 10 is connected to both the heating device 11 and the oil breakdown voltage detection device 7, and is used to measure the breakdown voltage, dielectric loss, viscosity, and total hydrocarbon gas content of the oil in the oil breakdown voltage detection device 7 under breakdown and high-temperature conditions of the prepared ternary mixed insulating oil. The computer 5 is connected to the heating device 11 and the second valve 14 via a controller, and controls the heating temperature of the heating device 11 and the opening and closing of the second valve 14. The computer 5 is also connected to the oil breakdown voltage detection device 7, oil dielectric loss detection device 8, oil viscosity measuring device 9, and oil total hydrocarbon gas detection device 10 via a controller.

[0023] Computer 5 controls the on / off time and opening / closing degree of the first valve 12 through the controller, thereby realizing the preparation of ternary mixed insulating oils with different proportions. The proportions of the prepared ternary mixed insulating oils are as follows: mineral oil from 1% to 99%, in 1% increments; soybean oil, under the same mineral oil proportion, from 1% to (100% - mineral oil proportion), in 1% increments; and the remaining proportions are filled with modified natural esters, resulting in a total of 4950 mixed oil proportions.

[0024] Furthermore, this device can also be used to comprehensively assess the condition of ternary mixed insulating oils. The specific assessment method is as follows: As shown in Figure 2, a method for evaluating ternary hybrid insulating oil includes the following steps: Step 1: Preparation of Ternary Mixed Insulating Oil: The computer 5 controls the on / off time of the first valve 12 to prepare ternary mixed insulating oils with different proportions. At the same time, the stirring impeller 13 is controlled to accelerate the mixing. Each proportion of ternary mixed insulating oil is stirred for 40 minutes and then left to stand for 10 minutes.

[0025] Step 2, Status Monitoring: After each settling and preparation of the ternary mixed insulating oil, computer 5 controls the opening of the second valve 14, and simultaneously activates the oil breakdown voltage detection device 7, oil dielectric loss detection device 8, oil viscosity measurement device 9, and oil total hydrocarbon gas detection device 10 to record the breakdown voltage, dielectric loss, and viscosity of the ternary mixed insulating oil in the current ternary mixed insulating oil storage device 6. Simultaneously, heating device 11 is activated, raising the temperature to 100℃ and maintaining it for 1 hour. The total hydrocarbon gas content in the ternary mixed insulating oil in the oil breakdown voltage detection device 7 is then detected by the oil total hydrocarbon gas detection device 10.

[0026] Step 3, State Assessment: Record the current breakdown voltage m of the ternary mixed insulating oil, and form the state quantity A representing the current insulation performance of the ternary mixed insulating oil according to Formula 1; record the current dielectric loss n of the ternary mixed insulating oil, and form the state quantity B representing the current dielectric loss of the ternary mixed insulating oil according to Formula 2; record the current viscosity x of the ternary mixed insulating oil, and form the viscosity state quantity C of the ternary mixed insulating oil according to Formula 3; record the total hydrocarbon content y in the oil after breakdown and the total hydrocarbon content k in the oil after heating, and form the stable state quantity D of the ternary mixed insulating oil according to Formula 4. Calculate the current evaluation coefficient U of the ternary mixed insulating oil according to Formula 5; finally, evaluate the state of the ternary mixed insulating oil according to the evaluation coefficient U, see Formula 6, that is, U < 10 is judged as poor, 10 ≤ U < 20 is judged as medium, 20 ≤ U < 30 is judged as good, and 30 ≤ U is judged as excellent.

[0027] ; ; ; ; ; .

[0028] This invention encompasses any substitutions, modifications, equivalent methods, and solutions made within the spirit and scope of this invention. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of this invention should be included within its protection scope. To provide the public with a thorough understanding of this invention, specific details have been described in detail in the above preferred embodiments; however, those skilled in the art can fully understand this invention even without these details. Several improvements and modifications can be made without departing from the principles of this invention, and these improvements and modifications should also be considered within the protection scope of this invention.

Claims

1. A ternary mixed insulating oil configuration evaluation device, comprising a mineral oil storage device (1), a soybean oil storage device (2), a PFAE oil storage device (3), and a ternary mixed oil storage device (6); wherein the mineral oil storage device (1), the soybean oil storage device (2), and the PFAE oil storage device (3) are respectively connected to the ternary mixed oil storage device (6) via a first pipeline (4), characterized in that, It also includes a computer (5), an oil breakdown voltage detection device (7), an oil dielectric loss detection device (8), an oil viscosity measuring device (9), an oil total hydrocarbon gas detection device (10), and a heating device (11); the oil breakdown voltage detection device (7), the oil dielectric loss detection device (8), the oil viscosity measuring device (9), and the heating device (11) are respectively connected to the ternary mixed oil storage device (6) through a second pipeline (15), and the oil total hydrocarbon gas detection device (10) is respectively connected to the heating device (11) and the oil breakdown voltage detection device (7); the computer (5) controls the oil breakdown voltage detection device (7) through a second pipeline (15). The device is connected to the oil breakdown voltage detection device (7), the oil dielectric loss detection device (8), the oil viscosity measurement device (9), and the oil total hydrocarbon gas detection device (10) to obtain the breakdown voltage, dielectric loss, and viscosity of the current ternary mixed insulating oil in the ternary mixed oil storage device (6) collected by the oil breakdown voltage detection device (7), the oil dielectric loss detection device (8), and the oil viscosity measurement device (9), as well as the data on the total hydrocarbon gas content in the oil breakdown voltage detection device (7) collected by the oil total hydrocarbon gas detection device (10), for the purpose of evaluating the current ternary mixed insulating oil.

2. The ternary mixed insulating oil configuration evaluation device according to claim 1, characterized in that, A first valve (12) is installed on the first pipeline (4), and the computer (5) is connected to the first valve (12) through a controller.

3. The ternary mixed insulating oil configuration evaluation device according to claim 1, characterized in that, The ternary mixed oil storage device (6) is equipped with a stirring impeller (13), and the computer (5) is connected to the motor of the stirring impeller (13) through a controller.

4. The ternary mixed insulating oil configuration evaluation device according to claim 1, characterized in that, A second valve (14) is installed on the second pipeline (15); the computer (5) is connected to the second valve (14) through the controller.

5. The ternary mixed insulating oil configuration evaluation device according to claim 1, characterized in that, The computer (5) is connected to the heating device (11) via a controller.

6. A method for evaluating the formulation of ternary hybrid insulating oil, characterized in that, The apparatus for evaluating the configuration of a ternary mixed insulating oil as described in any one of claims 1-5 includes the following steps: Step 1: According to the current configuration ratio, control the corresponding crude oil in the mineral oil storage device (1), soybean oil storage device (2), and PFAE oil storage device (3) to enter the ternary mixed oil storage device (6) to obtain the current ternary mixed insulating oil. Start the oil breakdown voltage detection device (7), oil dielectric loss detection device (8), oil viscosity measurement device (9), and oil total hydrocarbon gas detection device (10) to record the breakdown voltage, dielectric loss, viscosity of the current ternary mixed insulating oil in the ternary mixed oil storage device (6) and the total hydrocarbon gas content in the oil breakdown voltage detection device (7). Step 2: Record the breakdown voltage m of the current ternary mixed insulating oil to form the state quantity A representing the insulation performance of the current ternary mixed insulating oil; record the dielectric loss n of the current ternary mixed insulating oil to form the state quantity B representing the dielectric loss of the current ternary mixed insulating oil; record the viscosity x of the current ternary mixed insulating oil to form the viscosity state quantity C; record the total hydrocarbon content y in the oil after breakdown and the total hydrocarbon content k in the oil after heating to form the stability state quantity D of the current ternary mixed insulating oil. Step 3: Based on the current insulation performance state quantity A, dielectric loss state quantity B, and viscosity state quantity C of the ternary mixed insulating oil, compare the current evaluation coefficient U of the ternary mixed insulating oil with each threshold range, and determine the final state of the current ternary mixed insulating oil based on the comparison results.

7. The method for evaluating the formulation of a ternary hybrid insulating oil according to claim 6, characterized in that, The formula for calculating the evaluation coefficient U is: ； The evaluation coefficient U of the current ternary mixed insulating oil is compared with each threshold range. Based on the comparison results, the final state of the current ternary mixed insulating oil is determined. When U < 10, the final state of the current ternary mixed insulating oil is poor; when 10 ≤ U < 20, the final state of the current ternary mixed insulating oil is medium; when 20 ≤ U < 30, the final state of the current ternary mixed insulating oil is good; and when 30 ≤ U, the final state of the current ternary mixed insulating oil is excellent.

8. The method for evaluating the formulation of a ternary hybrid insulating oil according to claim 6, characterized in that, Formula 1 is used to form the current state quantity A, which represents the current insulating performance of the ternary mixed insulating oil; Formula 2 is used to form the current state quantity B, which represents the current state quantity B, which represents the current state quantity B, which represents the current state quantity C, which represents the current state quantity C, which represents the current state quantity C, which represents the current state quantity D, which represents the current state quantity D, which represents the current state quantity D, representing ... ； ； ； 。 9. The method for evaluating the formulation of a ternary hybrid insulating oil according to claim 6, characterized in that, In step one, the flow rate of oil in the mineral oil storage device (1), soybean oil storage device (2), and PFAE oil storage device (3) is controlled by computer (5), and ternary mixed insulating oils of different proportions are configured in the ternary mixed oil storage device (6); the heating device (11) is started, the temperature is raised to 100~110℃ and maintained for 1~1.5h, and the total hydrocarbon gas content in the oil breakdown voltage detection device (7) is detected.

10. The method for evaluating the configuration of a ternary mixed insulating oil according to claim 9, characterized in that, In step one, the ternary mixed insulating oil in the ternary mixed oil storage device (6) is kept in a stirring state. Each ternary mixed insulating oil of each configuration ratio is stirred for 30~50 minutes and then left to stand for 10~15 minutes.

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