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Testing of Directional Earth Fault Protections Using The Experimentally Obtained Fault Records
Holub, Martin ; Topolánek, David (referee) ; Orságová, Jaroslava (advisor)
Master thesis Testing of Directional Earth Fault Protections Using the Experimentally Obtained Fault Records deals with the protective functions of earth fault protections during earth faults in compensated medium voltage distribution network and their testing options. At the beginning of the thesis we charakterize operation of medium voltage distribution system in general. We begin with definition and characteristics of earth fault and its compartmentalization by the type of the fault, size of the transition resistance and duration. We also mention grounding methods of node winding transformer on medium voltage distribution network and we describe the most common of them in detail, i.e. network grouded through the arc suppression coil and its operation with automatic switching auxiliary resistor. In this part of the thesis we discuss the localization of the earth fault using passive static methods in compensated systems, which include wattmetric, admittance and conductance method. In next section we deal with the fault records stored in COMTRADE file format, its structure and all elements of its configuration and data file. We create and describe an example of converting ADF file format, recorded by Yokogawa oscilloscope fault recorder, into COMTRADE file format using Microsoft Excel program and M-File created in the MATLAB program. In the practical part we introduce workspace devices and software, which includes secondary testing equipment OMICRON CMC 256plus and its software OMICRON Test Universe with Advance Transplay test module, we further describe multifunctional earth fault protection RYo from PROTECTION & CONSULTING, s. r. o. and machine terminal REM 543 from ABB and their protective functions. The last part describes the actual testing of parallel connected earth fault protection with COMTRADE fault records by Advance Transplay test module in the OMICRON Test Universe. In the conclusion we describe evaluation of the suitability of each protective functions of earth fault protection in a variety of sizes the transition resistance at the earth fault location.
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Contactless Fault Indicator for MV Lines
Pernica, Drahomír ; Mišurec, Jiří (referee) ; Mišák,, Stanislav (referee) ; Toman, Petr (advisor)
The theoretical findings about methods of earth faults indication are elaborated in this thesis into form, which is applicable to design contactless indicator of failure states on MV lines. This design contains electromagnetic field sensors, evaluation device and software support. The higher effectiveness of clearing of fault and better health and asset protection is supposed by using of these indicators.
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Earth fault relay testing
Herůfek, Radek ; Topolánek, David (referee) ; Orságová, Jaroslava (advisor)
Bachelor thesis deals with an earth fault relay in compensated medium voltage distribution network. At the beginning of the thesis is described the method of operation compensated system and its advantages and disadvantages of using it. In addition, there is explained the definition of the ground fault, its types and there is outlined the method of solution asymmetrical single-phase fault. Thoroughly there is characterized distribution of voltages and currents, which is important for determination of affected and unaffected outlet. Among others, there is described the mode of action the arc suppression coil on caused fault current and also there are presented the auxiliary systems automation. In the next part the basic requirements for protections and its basic kinds are described. Finally the theoretical part describes principle of the earth fault relays and is presented means and methods used for indicate an affected outlet and earth fault localization. In the practical part, follows more detailed description of the protection REM 543 and testing equipment OMICRON CMC 256 +. In addition, there is explained connection process and setting selected functions and modules for testing earth fault relay. Assessment of generated and played transient disturbance records at the end.
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Testing of the admitance principle of the fault indicator
Musil, Milan ; Vyčítal, Václav (referee) ; Topolánek, David (advisor)
The thesis deals with the proposal, implementation and evaluation of test for fault condition indicators. Thesis focusing on earth fault indicators based on admittance principles. These indicators must be able to evaluate earth faults in compensated, compensated with auxiliary resistor, unearthed and high-resistance earthed networks. The proposed tests verify the current and voltage measurement errors in inputs including monitored characteristic variables such as conductance and susceptance. The proposed test are applied to a selected ample of the fault indicator. As part of the tests, the indicator is subjected to secondary test using the Omicron CMC256plus tester as well as test on fault records that have been converted to COMTRADE for this purpose. The last series of tests carried out uses the physical model of the medium voltage system, where the tested equipment is subjected to fault states in the compensated whit auxiliary resistor system and isolated system. Furthermore, part of the thesis is research of new methods of earth fault detection, including their principles and function description. Also included in the thesis is an overview of manufacturers of indicators, or protection, who are involved in the production of earth fault protection.
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Calculation of characteristic values of the earth fault in MV network.
Písařovic, Antonín ; Orságová, Jaroslava (referee) ; Toman, Petr (advisor)
In the bachelor thesis author deals with the earth fault in MV network. In the theoretical part of thesis there are identified existing faults occuring on power lines. The pivotal point of thesis is the analysis of the earth fault in network with ineffectively earthead node. In the parctical part author calculates the total capacity of specific network and according to the obtained results he proposes the suitable arc suppresion coil to reduce the earth current.
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Testing of the admitance principle of the fault indicator
Musil, Milan ; Vyčítal, Václav (referee) ; Topolánek, David (advisor)
The thesis deals with the proposal, implementation and evaluation of test for fault condition indicators. Thesis focusing on earth fault indicators based on admittance principles. These indicators must be able to evaluate earth faults in compensated, compensated with auxiliary resistor, unearthed and high-resistance earthed networks. The proposed tests verify the current and voltage measurement errors in inputs including monitored characteristic variables such as conductance and susceptance. The proposed test are applied to a selected ample of the fault indicator. As part of the tests, the indicator is subjected to secondary test using the Omicron CMC256plus tester as well as test on fault records that have been converted to COMTRADE for this purpose. The last series of tests carried out uses the physical model of the medium voltage system, where the tested equipment is subjected to fault states in the compensated whit auxiliary resistor system and isolated system. Furthermore, part of the thesis is research of new methods of earth fault detection, including their principles and function description. Also included in the thesis is an overview of manufacturers of indicators, or protection, who are involved in the production of earth fault protection.
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The Indication of Earth Faults in Overhead Lines
Pospíšil, Zdeněk ; Topolánek, David (referee) ; Toman, Petr (advisor)
This master´s thesis deals with the indication and localization of earth faults in overhead lines. Earth fault is the most frequently occurring type of fault in medium voltage overhead lines – it covers approx. 95% of all faults and is very difficult to indicate and localize them correctly and in time with currently available methods on the market. Therefore is very important to study earth fault and its indication, localization. The thesis consists of a theoretical and a practical part. The theoretical part deals with faults in overhead networks with different type of neutral grounding, mainly with one phase to the ground fault in the compensated, ungrounded, solidly grounded and via resistance grounded networks. Most of the theoretical part is dedicated to one phase to the ground fault in the compensated and ungrounded networks, where this type fault is called the earth fault. In the compensated and ungrounded networks is described in details behavior – voltage and current relations during both steady state and transient state earth fault. The theoretical part is further dedicated to detection methods of earth faults and their preconditions for use. There is described also in details the complete procedure of earth fault detection, which includes indication, unhealthy feeder determination and exact position or line section localization. End of the theoretical part is then focused on determination of accuracy requirements for measurement of basic quantities and computation of other parameters. The practical part deals with a work at medium distribution network model, which includes familiarization with the model, detailed verification of its functionality and behavior during the earth fault, obtaining faults records and algorithmization of methods: method of qu – diagram and method of first half - period, which are able to detect unhealthy feeder. This part of the thesis was put together based on a demand of company Mega, corp., which wanted to verify function of both above mentioned and by them not yet tested methods.
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Earth fault relay testing
Herůfek, Radek ; Topolánek, David (referee) ; Orságová, Jaroslava (advisor)
Bachelor thesis deals with an earth fault relay in compensated medium voltage distribution network. At the beginning of the thesis is described the method of operation compensated system and its advantages and disadvantages of using it. In addition, there is explained the definition of the ground fault, its types and there is outlined the method of solution asymmetrical single-phase fault. Thoroughly there is characterized distribution of voltages and currents, which is important for determination of affected and unaffected outlet. Among others, there is described the mode of action the arc suppression coil on caused fault current and also there are presented the auxiliary systems automation. In the next part the basic requirements for protections and its basic kinds are described. Finally the theoretical part describes principle of the earth fault relays and is presented means and methods used for indicate an affected outlet and earth fault localization. In the practical part, follows more detailed description of the protection REM 543 and testing equipment OMICRON CMC 256 +. In addition, there is explained connection process and setting selected functions and modules for testing earth fault relay. Assessment of generated and played transient disturbance records at the end.
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Calculation of characteristic values of the earth fault in MV network.
Písařovic, Antonín ; Orságová, Jaroslava (referee) ; Toman, Petr (advisor)
In the bachelor thesis author deals with the earth fault in MV network. In the theoretical part of thesis there are identified existing faults occuring on power lines. The pivotal point of thesis is the analysis of the earth fault in network with ineffectively earthead node. In the parctical part author calculates the total capacity of specific network and according to the obtained results he proposes the suitable arc suppresion coil to reduce the earth current.
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Contactless Fault Indicator for MV Lines
Pernica, Drahomír ; Mišurec, Jiří (referee) ; Mišák,, Stanislav (referee) ; Toman, Petr (advisor)
The theoretical findings about methods of earth faults indication are elaborated in this thesis into form, which is applicable to design contactless indicator of failure states on MV lines. This design contains electromagnetic field sensors, evaluation device and software support. The higher effectiveness of clearing of fault and better health and asset protection is supposed by using of these indicators.
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