CA2231877A1 - Process for evaluating thermal and dielectric strain of electrical machines and systems - Google Patents
Process for evaluating thermal and dielectric strain of electrical machines and systems Download PDFInfo
- Publication number
- CA2231877A1 CA2231877A1 CA 2231877 CA2231877A CA2231877A1 CA 2231877 A1 CA2231877 A1 CA 2231877A1 CA 2231877 CA2231877 CA 2231877 CA 2231877 A CA2231877 A CA 2231877A CA 2231877 A1 CA2231877 A1 CA 2231877A1
- Authority
- CA
- Canada
- Prior art keywords
- machine
- dielectric
- gaseous
- thermal
- moisture
- 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.)
- Abandoned
Links
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
- G01N33/0004—Gaseous mixtures, e.g. polluted air
- G01N33/0009—General constructional details of gas analysers, e.g. portable test equipment
- G01N33/0027—General constructional details of gas analysers, e.g. portable test equipment concerning the detector
- G01N33/0031—General constructional details of gas analysers, e.g. portable test equipment concerning the detector comprising two or more sensors, e.g. a sensor array
Abstract
EP-A 0 646 240 discloses a process for evaluating thermal and dielectric strain of rotating electrical machines (1) which have machine components provided with finishing varnish. The machines (1) are cooled with a gaseous coolant which is analysed in such a manner that gaseous fission products and decomposition products are determined and measured. These analytical values are evaluated jointly and the current operational state of the machine (1) is consequently established. In the present invention the gaseous coolant is also measured for moisture. A reference spectrum of moisture, dielectric and the composition of the thermal decomposition products is stored. The result is a cyclic comparison between the current, recorded measured values and the reference spectrum, and the measurement is evaluated on line. The moisture level of the coolant (2) is consequently also taken into consideration during measurement, it thereby being possible to conclude moisture condensation of high-voltage-conducting machine components. Coolant leakage can also be detected in good time using this method. There is also the current state of insulation of the active machine (1) components. If a defect is detected in the coolant (2), the machine (1) can always continue to be operated in an uncritical power range.
Description
METHOD FOR THE ASSESSMENT OF THERMAL AND DIELECTRIC STRAIN OF
ELECTRICAL MACHINES AND DEVICES
DESCRIPTION
The invention refers to a pn~cess for the assessment of thermal and dielectric 5 strain in electrical machines and devices, in particular rotating machines with components made of insulating materials and machine components coated with finishiing varnish, wherein the machines are equipped with a cooling system and cooled using a gaseous medium, and the gaseous medium is analyzed continuously or at freely definable intervals, namely in such a way that the 10 gasec,us pyrolysis products and decomposition products caused by thermal stress in the insulating materials or the finishing varnish and the ozone produced by dielectric stress are determined and measured, and these analysis values are assessed jointly, thus allowing the immediate operating condition of the machine to be determined.
15 Such a process is known from EP-A O 646 240.
Increasing machine load, as well as the increasing demands on operational safety for rotating electrical machines make improved monitoring methods necessary for the active parts of the machine, which are the winding system, inclucling the bar connections and circuit rings, as well as the armature 20 stampings.
If changes in major machine components, in particular the insulation, are detected on time, suitable measures can be taken and thus greater damage and longer standstills can be avoided.
Currently, the monitoring ol electrical machines - apart from the monitoring of 25 vibration - is carried out only with regard to the thermal state of the winding systern in the column of the machine.
A substantial disadvantage of machines with high-voltage winding is the fact that, ,due to the high voltage, heat sensors can only be located where there is no dielectric stress. For this reason, the sensors are located only in the area of the winding slot, where there is no dielectric stress due to the outer coronashielding.
This type of temperature monitoring has the disadvantage that only individual 5 points and small sections of the entire winding can be monitored.
The test method using data transmission via optical waveguides developed in recent years has the advant;3ge that it can be used despite dielectric stress, but it also has the disadvantage that it again monitors only individual points.
Moreover, the costs of such systems are economically unacceptable.
10 US-P', 3 427 880 describes a process and a design for the detection of overheating of parts in gas-cooled electrical machines, whereby the machine components and in particular the laminated sheets must be coated with a special coating that releases minute particles in the event of overheating, whichl can then be measured with suitable detectors. Thereby, the detector 15 is an ionisation chamber. Polymers are used as coating material, whereby minute particles are released by disintegration as soon as a certain temperatureis reached. Furthermore, radioactive components are used as indicator or as addith/es. The disadvantage of this system is that monitoring is not carried outon-llnle.
20 The object of the invention is to create a reliable permanent process for global monitoring of the active parl:s of an electric machine, in particular the laminated core, winding system, electrical connections and screw joints, soldering joints,etc.
This object is achieved with the invention. The invention is characterized by 25 the fact that there is additional measurement of the moisture in the gaseous cooling medium, and that an empirical or arithmetic reference spectrum of the moisture content (temperature ¦ mg H20/kg), dielectric (kV ¦,ug 03/kg) is stored, with cyclical comparison between the found values and the reference spectrum, whereby the evaluation of the tests is carried out on-line. Thus, the moisture content of the cooling medium is also taken into account in the measurement. This allows conclusions to be drawn with regard to possible dewing of high-voltage machine components. This is an advantage particularly 5 in the operation of machines in equatorial countries. Moreover, leakage in thecooling system can be identified at an early stage with this method. The decornposition products in the cooling medium in the original state of the machine are constantly compared with the current data, so that the actual state of insulation of the active parts of the machine is available. If a fault is 10 detected, the machine can still be operated in the uncritical range with this method of monitoring the cooling medium.
It is ol advantage to determine the thermal state and the aging of the insulation materials using the chain length of the decomposition products in the cooling medium. In a new machine, the hydrocarbon chains are shorter, e.g. CH4.
15 With iincreasing operating time, these chains become longer and longer, e.g.
C4H,o. Thus, it is possible to predict when a revision of the machine is due.
The invention is explained in more detail in the figure.
The figure shows the diagram of a rotating electrical machine with a closed cooling circuit. The cooling medium 2 heated up by the machine 1 is cooled 20 down in the condensers 3 and returned to the system. At a suitable position in this cooling system, preFerably after the condensers 3, the sensors 4 for analysis of the cooling medium 2 are introduced. The data are analyzed and evaluated, trends are determined in the plotter 5 and sent to the display 6.
Any significant change in the gaseous composition of the cooling medium 2 or 25 enhanced presence of individual specific gas components by comparison with the reference spectrum indicates an overload or pending defect of a machine component.
ELECTRICAL MACHINES AND DEVICES
DESCRIPTION
The invention refers to a pn~cess for the assessment of thermal and dielectric 5 strain in electrical machines and devices, in particular rotating machines with components made of insulating materials and machine components coated with finishiing varnish, wherein the machines are equipped with a cooling system and cooled using a gaseous medium, and the gaseous medium is analyzed continuously or at freely definable intervals, namely in such a way that the 10 gasec,us pyrolysis products and decomposition products caused by thermal stress in the insulating materials or the finishing varnish and the ozone produced by dielectric stress are determined and measured, and these analysis values are assessed jointly, thus allowing the immediate operating condition of the machine to be determined.
15 Such a process is known from EP-A O 646 240.
Increasing machine load, as well as the increasing demands on operational safety for rotating electrical machines make improved monitoring methods necessary for the active parts of the machine, which are the winding system, inclucling the bar connections and circuit rings, as well as the armature 20 stampings.
If changes in major machine components, in particular the insulation, are detected on time, suitable measures can be taken and thus greater damage and longer standstills can be avoided.
Currently, the monitoring ol electrical machines - apart from the monitoring of 25 vibration - is carried out only with regard to the thermal state of the winding systern in the column of the machine.
A substantial disadvantage of machines with high-voltage winding is the fact that, ,due to the high voltage, heat sensors can only be located where there is no dielectric stress. For this reason, the sensors are located only in the area of the winding slot, where there is no dielectric stress due to the outer coronashielding.
This type of temperature monitoring has the disadvantage that only individual 5 points and small sections of the entire winding can be monitored.
The test method using data transmission via optical waveguides developed in recent years has the advant;3ge that it can be used despite dielectric stress, but it also has the disadvantage that it again monitors only individual points.
Moreover, the costs of such systems are economically unacceptable.
10 US-P', 3 427 880 describes a process and a design for the detection of overheating of parts in gas-cooled electrical machines, whereby the machine components and in particular the laminated sheets must be coated with a special coating that releases minute particles in the event of overheating, whichl can then be measured with suitable detectors. Thereby, the detector 15 is an ionisation chamber. Polymers are used as coating material, whereby minute particles are released by disintegration as soon as a certain temperatureis reached. Furthermore, radioactive components are used as indicator or as addith/es. The disadvantage of this system is that monitoring is not carried outon-llnle.
20 The object of the invention is to create a reliable permanent process for global monitoring of the active parl:s of an electric machine, in particular the laminated core, winding system, electrical connections and screw joints, soldering joints,etc.
This object is achieved with the invention. The invention is characterized by 25 the fact that there is additional measurement of the moisture in the gaseous cooling medium, and that an empirical or arithmetic reference spectrum of the moisture content (temperature ¦ mg H20/kg), dielectric (kV ¦,ug 03/kg) is stored, with cyclical comparison between the found values and the reference spectrum, whereby the evaluation of the tests is carried out on-line. Thus, the moisture content of the cooling medium is also taken into account in the measurement. This allows conclusions to be drawn with regard to possible dewing of high-voltage machine components. This is an advantage particularly 5 in the operation of machines in equatorial countries. Moreover, leakage in thecooling system can be identified at an early stage with this method. The decornposition products in the cooling medium in the original state of the machine are constantly compared with the current data, so that the actual state of insulation of the active parts of the machine is available. If a fault is 10 detected, the machine can still be operated in the uncritical range with this method of monitoring the cooling medium.
It is ol advantage to determine the thermal state and the aging of the insulation materials using the chain length of the decomposition products in the cooling medium. In a new machine, the hydrocarbon chains are shorter, e.g. CH4.
15 With iincreasing operating time, these chains become longer and longer, e.g.
C4H,o. Thus, it is possible to predict when a revision of the machine is due.
The invention is explained in more detail in the figure.
The figure shows the diagram of a rotating electrical machine with a closed cooling circuit. The cooling medium 2 heated up by the machine 1 is cooled 20 down in the condensers 3 and returned to the system. At a suitable position in this cooling system, preFerably after the condensers 3, the sensors 4 for analysis of the cooling medium 2 are introduced. The data are analyzed and evaluated, trends are determined in the plotter 5 and sent to the display 6.
Any significant change in the gaseous composition of the cooling medium 2 or 25 enhanced presence of individual specific gas components by comparison with the reference spectrum indicates an overload or pending defect of a machine component.
Claims (2)
1. Process for the assessment of thermal and dielectric strain in electrical machines and devices, in particular rotating machines, with components of insulating material and machine components coated with finishing varnish, wherein the machines are equipped with a cooling system and cooled by a gaseous medium, and the gaseous medium is analyzed either continuously or at freely definable intervals, in such a way that the gaseous pyrolysis products and decomposition products caused by thermal stress in the insulating materials and the ozone caused by dielectric stress are determined and measured, and these analysis values are assessed jointly, thus allowing the immediate operating state of the machine to be determined, characterized in that there is additional measurement of the moisture in the gaseous cooling medium, and that an empiricial or arithmetic reference spectrum of the moisture content (temperature ~ mg H2O/kg), dielectric (kV ~ µg O3/kg) and the composition of the thermal decomposition products (temperature ~ mg CH/kg) is stored and comparison of the measured values and the reference spectrum is cyclically performed, whereby the measurements are carried out on-line.
2. Process according to claim 1, characterised in that the thermal condition and the aging of the insulating materials is determined by the chain length of the decomposition products, which are hydrocarbons, in the cooling medium.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| AT181395A AT402349B (en) | 1995-11-02 | 1995-11-02 | METHOD FOR EVALUATING THERMAL AND DIELECTRICAL LOADS OF ELECTRICAL MACHINES AND SYSTEMS |
| ATA1813/95 | 1995-11-02 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2231877A1 true CA2231877A1 (en) | 1997-05-09 |
Family
ID=3521546
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA 2231877 Abandoned CA2231877A1 (en) | 1995-11-02 | 1996-10-30 | Process for evaluating thermal and dielectric strain of electrical machines and systems |
Country Status (7)
| Country | Link |
|---|---|
| EP (1) | EP0858602B1 (en) |
| CN (1) | CN1201526A (en) |
| AT (1) | AT402349B (en) |
| CA (1) | CA2231877A1 (en) |
| DE (1) | DE59611160D1 (en) |
| ID (1) | ID18401A (en) |
| WO (1) | WO1997016725A1 (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100453888C (en) * | 2007-01-23 | 2009-01-21 | 范昌海 | Correction methods of online fluid system |
| CN106197737B (en) * | 2015-05-05 | 2019-11-12 | 哈尔滨亚源电力有限责任公司 | Generator insulation over-temperature on-Line Monitor Device |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| ATE179519T1 (en) * | 1992-06-17 | 1999-05-15 | Elin Energieversorgung | METHOD AND ARRANGEMENT FOR EVALUATION OF THERMAL AND DIELECTRIC STRESS |
-
1995
- 1995-11-02 AT AT181395A patent/AT402349B/en not_active IP Right Cessation
-
1996
- 1996-10-30 CN CN 96197970 patent/CN1201526A/en active Pending
- 1996-10-30 CA CA 2231877 patent/CA2231877A1/en not_active Abandoned
- 1996-10-30 EP EP96934176A patent/EP0858602B1/en not_active Expired - Lifetime
- 1996-10-30 WO PCT/AT1996/000208 patent/WO1997016725A1/en active IP Right Grant
- 1996-10-30 DE DE1996511160 patent/DE59611160D1/en not_active Expired - Lifetime
- 1996-10-31 ID IDP963147A patent/ID18401A/en unknown
Also Published As
| Publication number | Publication date |
|---|---|
| ID18401A (en) | 1998-04-02 |
| WO1997016725A1 (en) | 1997-05-09 |
| AT402349B (en) | 1997-04-25 |
| EP0858602A1 (en) | 1998-08-19 |
| DE59611160D1 (en) | 2005-01-13 |
| CN1201526A (en) | 1998-12-09 |
| EP0858602B1 (en) | 2004-12-08 |
| ATA181395A (en) | 1996-08-15 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Saha | Review of modern diagnostic techniques for assessing insulation condition in aged transformers | |
| CA2370174C (en) | Status detection apparatus and method for fluid-filled electrical equipment | |
| US5128269A (en) | Method for monitoring unusual signs in gas-charged apparatus | |
| Zhang et al. | Asset-management of transformers based on condition monitoring and standard diagnosis | |
| Singh et al. | Condition monitoring of power transformers-bibliography survey | |
| Van Bolhuis et al. | Monitoring and diagnostic of transformer solid insulation | |
| Bengtsson | Status and trends in transformer monitoring | |
| JP5653922B2 (en) | Method and device for detecting degradation of insulators in rotating machinery | |
| CN103765167B (en) | The combination of hydrogen and pressure sensor | |
| EP2691746B1 (en) | Combined hydrogen and pressure sensor assembly | |
| CN103562686A (en) | Sensor mounting into the temperature well of a transformer | |
| Arvind et al. | Condition monitoring of power transformer: A review | |
| Davies et al. | Testing distribution switchgear for partial discharge in the laboratory and the field | |
| Wetzer et al. | Diagnostic-and condition assessment-techniques for condition based maintenance | |
| CA2231877A1 (en) | Process for evaluating thermal and dielectric strain of electrical machines and systems | |
| US4101277A (en) | Detection of incipient faults in hydrogen-cooled generators | |
| Putra et al. | Dissolved gas analysis of generator step up transformer in Grati power plant using random forest based method | |
| Kim et al. | Study on decomposition gas characteristics and condition diagnosis for gas-insulated transformer by chemical analysis | |
| JPH0113300B2 (en) | ||
| Gutten et al. | Application of frequency method for analysis of power auto transformers | |
| JP3569421B2 (en) | Abnormality diagnosis method and abnormality diagnosis device for electrical equipment using aramid insulating material | |
| Wang et al. | Intensive monitoring and disassembling analysis of an 1000kV shunt reactor with abnormal grounding current and dissolved gas in oil | |
| Kaur et al. | Performance Assessment of IEEE/IEC Method and Duval Triangle technique for Transformer Incipient Fault Diagnosis | |
| Krishnan et al. | Review of the Monitoring Diagnostic Methods of Oil Immersed Transformers | |
| Gutten et al. | Diagnostics of transformer insulation by frequency domain spectroscopy |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| FZDE | Dead |