CN110940801A - Method for obtaining activation energy of dry insulation equipment based on equal conversion rate method - Google Patents

Method for obtaining activation energy of dry insulation equipment based on equal conversion rate method Download PDF

Info

Publication number
CN110940801A
CN110940801A CN201911247818.2A CN201911247818A CN110940801A CN 110940801 A CN110940801 A CN 110940801A CN 201911247818 A CN201911247818 A CN 201911247818A CN 110940801 A CN110940801 A CN 110940801A
Authority
CN
China
Prior art keywords
activation energy
equation
dry
temperature
curve
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN201911247818.2A
Other languages
Chinese (zh)
Inventor
张鑫
王伟
魏菊芳
刘广振
刘卫平
张心洁
文清丰
朱明正
王楠
王旭强
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
State Grid Corp of China SGCC
State Grid Tianjin Electric Power Co Ltd
Original Assignee
State Grid Corp of China SGCC
State Grid Tianjin Electric Power Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by State Grid Corp of China SGCC, State Grid Tianjin Electric Power Co Ltd filed Critical State Grid Corp of China SGCC
Priority to CN201911247818.2A priority Critical patent/CN110940801A/en
Publication of CN110940801A publication Critical patent/CN110940801A/en
Pending legal-status Critical Current

Links

Images

Classifications

    • GPHYSICS
    • G01MEASURING; TESTING
    • G01NINVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N33/00Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
    • G01N33/44Resins; Plastics; Rubber; Leather
    • G01N33/442Resins; Plastics

Landscapes

  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Food Science & Technology (AREA)
  • Medicinal Chemistry (AREA)
  • Physics & Mathematics (AREA)
  • Analytical Chemistry (AREA)
  • Biochemistry (AREA)
  • General Health & Medical Sciences (AREA)
  • General Physics & Mathematics (AREA)
  • Immunology (AREA)
  • Pathology (AREA)
  • Testing Relating To Insulation (AREA)

Abstract

本发明公开了一种基于等转化率法的干式绝缘设备活化能获取方法,包含以下步骤:步骤一:制备环氧树脂样品;步骤二:开展热失重试验;步骤三:计算活化能。使用本发明可以在热失重试验基础上,对干式绝缘设备绝缘材料活化能进行定量计算。另外,等转化率方法在计算干式绝缘材料化学反应活化能方面具有以下优点:1.该方法对化学反应所处阶段不敏感,特别是在化学反应初期,同样可以较为准确地计算活化能;2.可以排除不同试样质量差异的影响,计算准确度高。

Figure 201911247818

The invention discloses a method for obtaining activation energy of dry insulation equipment based on an equal conversion rate method. The invention can quantitatively calculate the activation energy of the insulating material of the dry-type insulating equipment on the basis of the thermal weight loss test. In addition, the equal conversion rate method has the following advantages in calculating the activation energy of the chemical reaction of dry insulating materials: 1. The method is not sensitive to the stage of the chemical reaction, especially in the early stage of the chemical reaction, the activation energy can also be calculated more accurately; 2. The influence of the quality difference of different samples can be excluded, and the calculation accuracy is high.

Figure 201911247818

Description

Method for acquiring activation energy of dry-type insulating equipment based on equal conversion rate method
Technical Field
The invention relates to the technical field of transformer operation and test, in particular to a dry-type insulation equipment activation energy obtaining method based on an equal conversion rate method.
Background
Dry-type insulation equipment such as dry-type transformers, dry-type reactors and the like are important electrical equipment in power systems, undertake the tasks of converting voltage, distributing and transmitting electric energy and the like, and the operation state of the dry-type insulation equipment directly influences the safe and stable operation of the whole power grid. The dry type transformer has the advantages of good fireproof performance, strong heat resistance and short circuit resistance, safety, environmental protection and the like, but the main insulation of the dry type equipment is cast and molded by adopting an epoxy resin material, so that the insulation performance, the insulation aging degree and the residual life of the dry type equipment are difficult to detect and evaluate, and the effect of the existing method for detecting the macroscopic electrical parameters such as the local discharge, the dielectric performance and the like of the insulation monitoring of the dry type insulation equipment is poor.
The activation energy is a parameter capable of measuring the difficulty of a chemical reaction and has important significance in the chemical reaction. By accurately acquiring the activation energy of the dry type insulation device, the aging degree of the dry type insulation device can be detected from the nature of the insulation material. Through search, no activation energy acquisition method applicable to dry insulation equipment exists at present. The patent provides a dry-type insulation equipment activation energy obtaining method based on an equal conversion rate method, so that the activation energy is accurately measured, and a foundation is laid for evaluating the aging state of the dry-type insulation equipment.
Disclosure of Invention
In order to meet the requirement for obtaining the activation energy of the dry-type insulation equipment in the prior art, the invention aims to provide a method for obtaining the activation energy of the dry-type insulation equipment based on an equal conversion rate method.
In order to achieve the purpose of the invention, the invention provides a dry type insulation equipment activation energy obtaining method based on an equal conversion rate method, which comprises the following steps:
the method comprises the following steps: preparing an epoxy resin sample;
step two: carrying out a thermal weight loss test to obtain thermal weight loss curves TG and first-order differential curves DTG of a plurality of groups of epoxy resin samples;
step three: calculation of activation energy
The activation energy is defined by the Arrhenius equation for chemical reactions, as follows:
Figure BDA0002308179300000021
in formula (1), k represents a chemical reaction rate; a is called that the pre-factor has the same factor as k, and can be regarded as the limit value of k at high temperature; r is a universal gas constant; t is the absolute temperature; eaThe energy factor is the activation energy of the chemical reaction;
in the thermal ageing reaction of dry insulation equipment, the assumption exists that the epoxy polymer reaction process depends only on the conversion α and the temperature T, which are independent of each other, and the kinetic equation of the heterogeneous reaction at an indefinite temperature can be expressed in the form:
Figure BDA0002308179300000022
in the formula (2), t is time, k (T) is a temperature relation of rate constant, f (α) is a function of reaction mechanism, and the formula (1) can be converted into the following by converting temperature and time at the time of linear temperature rise:
Figure BDA0002308179300000023
Figure BDA0002308179300000024
β -dT/dT is the rate of temperature rise;
the heterogeneous system obtained by substituting the formula (1) into the formula (3) has a common kinetic equation under a non-constant temperature condition, such as the formula (5);
Figure BDA0002308179300000025
selecting one α in the TG plot1It is taken as a horizontal line, and the horizontal line intersects the curve at an intersection point (α)1,T11)(α1,T12) …, the ramp rates corresponding to them are β1、β2…, and selecting another α2Repeating the above process, another set of data (α) is obtained2,T21)、(α2,T22) …, their corresponding ramp rates are still β1、β2…
Formula (5) can be modified as follows:
Figure BDA0002308179300000031
at α1~α2In the range of β1The two-sided integration of equation (6) can be obtained
Figure BDA0002308179300000032
For β2The two-sided integration of equation (6) can be obtained
Figure BDA0002308179300000033
Subtracting the above two equations can obtain:
Figure BDA0002308179300000034
the dry type can be obtained by solving the formula (9)Activation energy E of insulating devicea
Compared with the prior art, the invention has the advantages that,
the method can be used for quantitatively calculating the activation energy of the insulating material of the dry-type insulating equipment on the basis of the thermal weight loss test.
In addition, the equal conversion method has the following advantages in calculating the chemical reaction activation energy of the dry insulating material:
1. the method is insensitive to the stage of the chemical reaction, and particularly can accurately calculate the activation energy at the initial stage of the chemical reaction;
2. the influence of different sample quality differences can be eliminated, and the calculation accuracy is high.
Drawings
FIG. 1 is a schematic representation of an epoxy resin sample of the present application;
FIG. 2 is a graph of TG of the present application;
fig. 3 is a graph showing the DTG of the present application.
Detailed Description
The invention is described in further detail below with reference to the figures and specific examples. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict.
Examples
The embodiment of the invention relates to a method for acquiring activation energy of dry type insulation equipment based on equal conversion rate, which mainly comprises the following steps:
the method comprises the following steps: preparation of epoxy resin samples
And (3) punching and slicing the epoxy resin insulating material poured and cured in the same batch and process of the dry-type insulating equipment to prepare a plurality of epoxy resin slices, and forming a sample group for thermal weight loss test. A typical sample is shown in figure 1.
Step two: carrying out a thermal weight loss test
Heating the sample to be tested in a high-purity nitrogen atmosphere by using a synchronous thermal analysis combination instrument, setting the heating rates of 5K/min, 10K/min, 15K/min, 20K/min and 25K/min respectively, raising the temperature in the furnace to 800 ℃, and recording the change data of the sample mass along with the temperature by using a computer to obtain the thermogravimetric curves TG and the first-order differential curves DTG of the curves of the multiple groups of epoxy resin samples. Typical TG curves and DTG curves are shown in fig. 2 and 3.
Step three: calculation of activation energy
The activation energy can be defined by the Arrhenius equation for chemical reactions, as follows:
Figure BDA0002308179300000041
in formula (1), k represents a chemical reaction rate; a is called a pre-factor (or called a frequency factor) and has the same factor as k, and can be considered as the limit value of k at high temperature; r is a universal gas constant; t is the absolute temperature; eaHas an energy factor, namely the activation energy of the chemical reaction.
In the thermal ageing reaction of dry insulation equipment, the assumption exists that the epoxy polymer reaction process depends only on the conversion α and the temperature T, which are independent of each other, and the kinetic equation of the heterogeneous reaction at an indefinite temperature can be expressed in the form:
Figure BDA0002308179300000051
in formula (2), t is time, k (T) is a temperature relation of rate constant, f (α) is a function of reaction mechanism, and formula (1) can be converted into a reaction product by converting temperature and time at linear temperature rise
Figure BDA0002308179300000052
Figure BDA0002308179300000053
β -dT/dT is the rate of temperature rise, which is a constant value in most experiments.
The heterogeneous system obtained by substituting the formula (1) into the formula (3) has a common kinetic equation under the non-constant temperature condition, such as the formula (5):
Figure BDA0002308179300000054
selecting one α in TG plot 21It is taken as a horizontal line, and the horizontal line intersects the curve at an intersection point (α)1,T11)(α1,T12) …, the ramp rates corresponding to them are β1、β2…, and selecting another α2Repeating the above process, another set of data (α) is obtained2,T21)、(α2,T22) …, their corresponding ramp rates are still β1、β2…
Formula (5) can be modified as follows:
Figure BDA0002308179300000055
at α1~α2In the range of β1The two-sided integration of equation (6) can be obtained
Figure BDA0002308179300000056
For β2The two-sided integration of equation (6) can be obtained
Figure BDA0002308179300000057
Subtracting the above two equations can obtain:
Figure BDA0002308179300000061
solving the formula (9) to obtain the activation energy E of the dry-type insulation equipmenta
In the thermal weight loss test of the insulating material of the dry type insulating equipment, different chemical reaction stages may exist, so that the reflection rate of each stage is different, and different wave troughs appear on the DTG curve chart 3. in the activation energy acquisition method based on the equal conversion rate method, α1As a starting point for the calculation section, it is decided which stage of the activation energy is calculated for the activation energy of the insulating material, e.g., α1And α2Can span the whole process of the thermal weight loss test, and the E obtained at the momentaα is the activation energy of new epoxy resin insulating material1And α2May be selected only in the vicinity of the second trough, in which case E is obtainedaThe activation energy is the activation energy of the dry-type insulation equipment which has been subjected to secondary curing after a period of time and in a certain aging state in normal operation.
The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.

Claims (1)

1.一种基于等转化率法的干式绝缘设备活化能获取方法,其特征是:包含以下步骤:1. a method for obtaining activation energy of dry-type insulating equipment based on equal conversion rate method, is characterized in that: comprise the following steps: 步骤一:制备环氧树脂样品;Step 1: prepare epoxy resin samples; 步骤二:开展热失重试验,获得多组环氧树脂样本的热失重曲线TG以及曲线的一阶微分曲线DTG;Step 2: Carry out the thermal weight loss test, and obtain the thermal weight loss curve TG and the first-order differential curve DTG of the multiple groups of epoxy resin samples; 步骤三:计算活化能Step 3: Calculate the activation energy 活化能由化学反应的Arrhenius方程定义,如下式:The activation energy is defined by the Arrhenius equation for chemical reactions, as follows:
Figure FDA0002308179290000011
Figure FDA0002308179290000011
式(1)中,k表示化学反应速率;A称为指前因子与k具有相同的因次,可以认为高温时k的极限值;R为普适气体常数;T为绝对温度;Ea具有能量因次,即为化学反应的活化能;In formula (1), k represents the chemical reaction rate; A is called the pre-exponential factor and has the same dimension as k, which can be considered as the limit value of k at high temperature; R is the universal gas constant; T is the absolute temperature; E a has The energy dimension is the activation energy of a chemical reaction; 在干式绝缘设备的热老化反应中存在如下假设:环氧树脂聚合物反应过程仅取决于转化率α和温度T,这两个参数是相互独立的,在不定温、非均相反应的动力学方程可以表示为以下形式:The following assumptions exist in the thermal aging reaction of dry insulation equipment: the reaction process of epoxy resin polymer only depends on the conversion rate α and the temperature T, these two parameters are independent of each other, and the kinetic energy of the indeterminate temperature and heterogeneous reaction The learning equation can be expressed in the following form:
Figure FDA0002308179290000012
Figure FDA0002308179290000012
式(2)中,t为时间,k(T)为速率常数的温度关系式,f(α)为反应机理函数,In formula (2), t is the time, k(T) is the temperature relationship of the rate constant, f(α) is the reaction mechanism function, 在线性升温时,通过温度与时间的转化,式(1)可以转化为:During linear heating, through the conversion of temperature and time, formula (1) can be converted into:
Figure FDA0002308179290000013
Figure FDA0002308179290000013
Figure FDA0002308179290000014
Figure FDA0002308179290000014
β=dT/dt为升温速率;β=dT/dt is the heating rate; 将式(1)代入式(3)可得非均相体系在非定温条件下常用动力学方程式,如式(5);Substituting Equation (1) into Equation (3) can obtain the commonly used kinetic equations of heterogeneous systems under non-constant temperature conditions, such as Equation (5);
Figure FDA0002308179290000021
Figure FDA0002308179290000021
在TG曲线图中选定一个α1,以它做水平线,这一水平线和曲线相交,交点为(α1,T11)(α1,T12)…,与它们对应的升温速率是β1、β2…,再选定一个α2重复上面的过程,就可得到另外一组数据(α2,T21)、(α2,T22)…,与它们对应的升温速率仍然是β1、β2…Select an α 1 in the TG curve graph, and use it as a horizontal line. This horizontal line intersects with the curve, and the intersection is (α 1 , T 11 )(α 1 , T 12 )..., and the corresponding heating rate is β 1 , β 2 ..., and then select a α 2 to repeat the above process, you can get another set of data (α 2 , T 21 ), (α 2 , T 22 )..., and their corresponding heating rate is still β 1 , β 2... ; 式(5)可变形为:Equation (5) can be transformed into:
Figure FDA0002308179290000022
Figure FDA0002308179290000022
在α1~α2范围内,对于β1的曲线,对式(6)进行两边积分可得In the range of α 1~ α 2 , for the curve of β 1 , the two-sided integration of equation (6) can be obtained
Figure FDA0002308179290000023
Figure FDA0002308179290000023
对于β2的曲线,对式(6)进行两边积分可得For the curve of β 2 , integrating both sides of equation (6) can be obtained
Figure FDA0002308179290000024
Figure FDA0002308179290000024
将上述两式相减可得:Subtract the above two equations to get:
Figure FDA0002308179290000025
Figure FDA0002308179290000025
对式(9)进行求解,即可求得干式绝缘设备活化能EaSolving equation (9), the activation energy E a of dry insulation equipment can be obtained.
CN201911247818.2A 2019-12-09 2019-12-09 Method for obtaining activation energy of dry insulation equipment based on equal conversion rate method Pending CN110940801A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201911247818.2A CN110940801A (en) 2019-12-09 2019-12-09 Method for obtaining activation energy of dry insulation equipment based on equal conversion rate method

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201911247818.2A CN110940801A (en) 2019-12-09 2019-12-09 Method for obtaining activation energy of dry insulation equipment based on equal conversion rate method

Publications (1)

Publication Number Publication Date
CN110940801A true CN110940801A (en) 2020-03-31

Family

ID=69909193

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201911247818.2A Pending CN110940801A (en) 2019-12-09 2019-12-09 Method for obtaining activation energy of dry insulation equipment based on equal conversion rate method

Country Status (1)

Country Link
CN (1) CN110940801A (en)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111366603A (en) * 2020-04-13 2020-07-03 国网天津市电力公司电力科学研究院 KISSINGER method-based dry-type insulation equipment activation energy acquisition method
CN111999610A (en) * 2020-08-11 2020-11-27 国网天津市电力公司电力科学研究院 Dry-type insulation equipment aging evaluation and service life prediction method based on activation energy
CN114113924A (en) * 2021-10-22 2022-03-01 西南交通大学 A method for evaluating the damage degree of epoxy resin by short-circuit electrodynamic force
CN114167221A (en) * 2021-12-13 2022-03-11 华北电力大学(保定) Epoxy resin insulation aging discrimination and inspection method under different voltage frequencies

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110544513A (en) * 2019-07-17 2019-12-06 中国地质大学(武汉) Calculation Method of Pyrolysis Kinetic Parameters of Carbonized Combustibles Based on Single-peak Pyrolysis Curve

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110544513A (en) * 2019-07-17 2019-12-06 中国地质大学(武汉) Calculation Method of Pyrolysis Kinetic Parameters of Carbonized Combustibles Based on Single-peak Pyrolysis Curve

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
刘晓东等: "环氧树脂和环氧/环硫树脂与胺的固化反应动力学 ", 《化工学报》 *
左金琼: "《热分析中活化能的求解与分析》", 《中国优秀硕士论文全文数据库 工程科技Ⅰ辑》 *

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111366603A (en) * 2020-04-13 2020-07-03 国网天津市电力公司电力科学研究院 KISSINGER method-based dry-type insulation equipment activation energy acquisition method
CN111999610A (en) * 2020-08-11 2020-11-27 国网天津市电力公司电力科学研究院 Dry-type insulation equipment aging evaluation and service life prediction method based on activation energy
CN114113924A (en) * 2021-10-22 2022-03-01 西南交通大学 A method for evaluating the damage degree of epoxy resin by short-circuit electrodynamic force
CN114113924B (en) * 2021-10-22 2022-07-19 西南交通大学 Method for evaluating damage degree of short-circuit electrodynamic force to epoxy resin
CN114167221A (en) * 2021-12-13 2022-03-11 华北电力大学(保定) Epoxy resin insulation aging discrimination and inspection method under different voltage frequencies
CN114167221B (en) * 2021-12-13 2023-06-13 华北电力大学(保定) Epoxy resin insulation aging discrimination and test method under different voltage frequencies

Similar Documents

Publication Publication Date Title
CN110940801A (en) Method for obtaining activation energy of dry insulation equipment based on equal conversion rate method
CN111337418B (en) Method for evaluating service life of polyolefin cable insulating material for nuclear power station
CN105203879B (en) A kind of disc insulator lifetime estimation method based on artificial accelerated aging test
CN103149452B (en) Method for evaluating ageing state of paper oil insulation
CN104793111A (en) Insulating cable residual service life comprehensive evaluation method based on physical, chemical and electric properties
CN109060158A (en) Oil-immersed transformer Intellectual Gauge of Temperature and its data processing method
CN110987226A (en) Dry-type reactor overheating fault early warning system based on distributed optical fiber sensing
CN104459380A (en) Method and system for measuring cable load carrying capacity
CN111366603A (en) KISSINGER method-based dry-type insulation equipment activation energy acquisition method
CN112305338B (en) Aging degree detection method and system for dry-type transformer
CN104713799B (en) A kind of sulphurated siliastic performance estimating method
CN104459412A (en) Transformer thermal ageing real-time simulation measurement device and application thereof
CN104199484A (en) Method and device for measuring intelligent cooling control temperature of oil-immersed transformer based on overall temperature monitoring
CN112698245A (en) Transformer insulation reliability analysis method with less failure data
CN110879291A (en) Method for acquiring activation energy of dry-type insulating equipment based on FWO method
CN102384968A (en) Test device for evaluating service life of transformer oil
CN110879290A (en) Activation energy acquisition method for dry insulation equipment based on static method
CN102998338B (en) Dielectric response characteristic-based insulation dampness diagnosis method for transformer oil paper
CN117740862A (en) Control device, method and equipment for thermal elongation test of cable insulating layer
RU2399910C1 (en) Method for thermodynamic acoustic-emission standardisation and system for realising said method
Kim et al. Thermal analysis and statistical evaluation of EPR used in nuclear power plants
CN103808291B (en) measuring system
CN109541123B (en) A kind of solid oxidation test device and its application
CN118067290B (en) Residual stress distribution detection method of epoxy insulation parts based on infrared
CN106092763A (en) Detection method based on cable insulating high temperature resistant sheath pressure

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
WD01 Invention patent application deemed withdrawn after publication

Application publication date: 20200331

WD01 Invention patent application deemed withdrawn after publication