TY - JOUR A1 - Küchler, Andreas A1 - Hinrichsen, V. T1 - Grundlagen der elektrischen Feldsteuerung BT - Energietechnische Gesellschaft im VDE (ETG) JF - ETG Mitgliederinformationen Y1 - 2012 IS - 2 ER - TY - JOUR A1 - Küchler, Andreas A1 - Hammer, F. T1 - Bewährte Silikonschirmdurchführungen für erhöhte Sicherheit und Verschmutzungsfestigkeit JF - Elektrizitätswirtschaft Y1 - 1991 UR - http://permalink.bibkatalog.de/BV002576215 VL - 90 IS - 11 SP - 604 EP - 608 ER - TY - JOUR A1 - Küchler, Andreas A1 - Schwab, A. T1 - Räumlich ausgedehnte Sensoren für transiente elektromagnetische Felder JF - Archiv für Elektrotechnik Y1 - 1987 UR - http://permalink.bibkatalog.de/BV013241178 VL - 70 SP - 341 EP - 347 ER - TY - JOUR A1 - Küchler, Andreas A1 - Hammer, F. T1 - Insulating Systems for HVDC Power Apparatus JF - IEEE Transactions on Electrical Insulation Y1 - 1992 UR - http://permalink.bibkatalog.de/BV013529386 VL - 27 IS - 3 ER - TY - JOUR A1 - Küchler, Andreas A1 - Schwab, A. T1 - Zum Begriff der Netzfrequenz bei Netzstörungen JF - Elektrizitätswirtschaft Y1 - 1987 UR - http://permalink.bibkatalog.de/BV002576215 VL - 86 SP - 308 EP - 310 ER - TY - JOUR A1 - Küchler, Andreas T1 - Master Research Program Elektro- und Informationstechnik JF - DNH Die Neue Hochschule Y1 - 2007 UR - http://permalink.bibkatalog.de/BV002668906 VL - 47 IS - 3/06 SP - 12 EP - 14 ER - TY - JOUR A1 - Küchler, Andreas T1 - Induktivität von Hochspannungskondensatoren JF - etz Elektrotechnische Zeitschrift Y1 - 1998 UR - http://permalink.bibkatalog.de/BV002580706 VL - 109 SP - 1070 EP - 1075 ER - TY - CHAP A1 - Küchler, Andreas T1 - Application of HV Test Methods to the Evaluation of LV Motor Insulation Quality BT - optim ‘98 T2 - 6th Int. Conf. on Optimization of Electrical and Electronic Equipment Y1 - 1998 CY - Brasov, Romania ER - TY - JOUR A1 - Küchler, Andreas A1 - Bedel, T. T1 - Dielectric Diagnosis of Water Content in Transformer Insulation Systems JF - ETEP European Trans. on El. Power Y1 - 2001 VL - 11 IS - 1 PB - VDE CY - Offenbach ER - TY - CHAP A1 - Dahinden, V. A1 - Schultz, K. A1 - Küchler, Andreas T1 - The Function of Solid Insulation in Transformers T2 - Transform ‘98 Y1 - 1998 CY - München ER - TY - CHAP A1 - Küchler, Andreas A1 - Rashwan, M.M. A1 - McDermid, W. A1 - Hammer, F. T1 - On the Design, Testing and Operating Experience of Composite Dry Bushings in HVDC T2 - 5th Int. Conf. on AC and DC Power Transmission Y1 - 1991 CY - London ER - TY - CHAP A1 - Küchler, Andreas A1 - Hammer, F. T1 - Suppression of Surface Discharges and Flashover on Dielectric Surfaces BT - 9th ISH Int. Symp. on High Voltage Engineering Y1 - 1995 IS - 8032 CY - Graz, Österreich ER - TY - CHAP A1 - Küchler, Andreas A1 - Hammer, F. T1 - Insulating Systems for HVDC Power Apparatus T2 - 3rd Int. Conf. on Properties Y1 - 1995 CY - Graz, Österreich ER - TY - CHAP A1 - Küchler, Andreas A1 - Hammer, F. T1 - Application of Dielectric Materials Y1 - 1991 SP - 965 EP - 968 CY - Tokyo ER - TY - CHAP A1 - Targitay, Deniz A1 - Roth, Lisa A1 - Zink, Markus H. A1 - Küchler, Andreas A1 - Bier, Markus A1 - Kobus, Maja A1 - Geißler, Michael A1 - Schlittler, Balz T1 - An FEM simulation model of oil-pressboard insulating systems for HVDC transformers T2 - 23rd International Symposium on High Voltage Engineering (ISH 2023) N2 - In this contribution, a simulation model for the description of the nonlinear dielectric behaviour of an insulation system composed of mineral oil and oil-impregnated pressboard is presented. The model was verified by comparing the simulation results with electric field and current measurements. At the outset, the ideal case, where a homogeneous initial charge carrier distribution according to the definition of ohmic conductivity is present, is analysed to establish the preliminary foundations pertaining to a typical measurement. Following that, the influence of distinct charge carriers on the measured quantities are investigated by altering their parametrisations. In contrast to the ideal case, a real measurement reveals a current trend, that can be explained by an excess amount of initial charge carriers related to the oil-impregnated pressboard layers. Potential possibilities to the origin of the surplus are discussed. Furthermore, it is shown that the dissociable and intrinsic charge carriers alone can reconstruct the measured quantities in terms of the transient behaviour. This points out that, for the field strength studied here ( E ≤ 1 kV/mm ), the charging of the highly resistive pressboard barriers is dominated by the dissociation of charge carriers in the oil gaps. KW - Mineral oil KW - Oil-impregnated pressboard KW - Poisson-Nernst-Planck theory KW - Ion drift KW - Electric current Y1 - 2023 UR - https://doi.org/10.1049/icp.2024.0488 PB - Institution of Engineering & Technology ER - TY - JOUR A1 - Zink, Markus H. A1 - Küchler, Andreas A1 - Berger, Frank T1 - Kompensation des Temperatureinflusses auf dielektrische Messungen im Zeitbereich zur Beschreibung von Isolierwerkstoffen JF - ETG-Fachtagung „Grenzflächen in elektrischen Isoliersystemen“ Y1 - 2013 CY - Dresden ER - TY - CHAP A1 - Wirth, Isabell A1 - Sturm, Sebastian A1 - Küchler, Andreas A1 - Zink, Markus H. A1 - Berger, Frank A1 - Schnitzler, Tim T1 - Berücksichtigung von Leitungs- und Polarisationsmechanismen in transienten FEM-Simulationen von HGÜ-Isoliersystemen T2 - VDE-Hochspannungstechnik 2018, Berlin N2 - The calculation of electrical field distributions in insulation systems for high voltage direct current (HVDC) transmission using the finite element method (FEM) usually only considers the dielectric properties in the form of permittivities and conductivities. Due to not sufficiently well simulated transient processes, state of the art is considering the polarization processes by equivalent network models. The application and implementation of polarization mechanisms in a FEM soft- ware closes this gap and allows calculating the electric field distribution more precisely. An implementation of additional differential equations, according to the RC-network model, describing the field dependent polarization mechanisms, are complementing the displacement and conduction current. Material equations and their parameters are determined by measuring the polarization and depolarization currents (PDC). These equations are necessary for both the RC-network models and the differential equations for the FEM. They can be adapted to the actual temperatures in the insulation system. Hence, the necessarily multidimensional electric field calculations of complex insulation systems with stationary or transient temperature-gradients are possible. The described calculation method is verified by reactionless fieldmill voltmeter measurements of transient voltage profiles at the grading foils of modified high voltage DC-bushings. A better accuracy is achieved for the simulation of transient and stationary potential distributions. N2 - Bei der Berechnung elektrischer Feldverteilungen in Isoliersystemen für die Hochspannungsgleichstromübertragung (HGÜ) mit Hilfe der Finiten Elemente Methode (FEM) werden die dielektrischen Eigenschaften bisher meist in Form von Permittivitäten und Leitfähigkeiten berücksichtigt. Da die transienten Verläufe nicht ausreichend genau abgebildet werden, ist Stand der Technik die Polarisationsvorgänge exakter durch Netzwerkmodelle nachzubilden. Durch Implementierung von Polarisationsmechanismen in einem FEM-Programm wurde diese Lücke geschlossen und es können nun elektrische Feldverteilungen vor allem im transienten Zustand wesentlich präziser berechnet werden. In Analogie zum RC-Netzwerkmodell werden hierfür zusätzlich zu den Gleichungen, die die feldabhängigen Verschiebungs- und Leitungsströme beschreiben, weitere Differentialgleichungen eingesetzt, welche die ebenfalls feldabhängigen Polarisationsströme abbilden. Die Materialfunktionen und ihre Parameter werden durch Messung von Polarisations- und Depolarisationsströmen (PDC) ermittelt. Diese Gleichungen werden sowohl für die RC-Netzwerkmodelle als auch für die Aufstellung der Differentialgleichungen für die FEM benötigt. Sie können unmittelbar auf die am jeweiligen Ort im Isoliersystem herrschende Temperatur umgerechnet werden. Somit sind transiente elektrische Feldberechnungen auch für komplexe Isoliersysteme möglich, die sich nur durch mehrdimensionale FEM-Modelle abbilden lassen und in denen oftmals stationäre oder transiente Temperaturgradienten vorliegen. Das beschriebene Berechnungsverfahren wird durch die rückwirkungsfreie Messung transienter Potentialverläufe an den Steuerbelägen von entsprechend modifizierten kondensatorgesteuerten Hochspannungsdurchführungen verifiziert. Dabei kann eine höhere Übereinstimmung der transienten und stationären Potentialverläufe zwischen Simulation und Messung erzielt werden. Y1 - 2018 UR - https://ieeexplore.ieee.org/stamp/stamp.jsp?arnumber=8576769 ER - TY - CHAP A1 - Koch, Myriam A1 - Hohloch, Jens A1 - Wirth, Isabell A1 - Sturm, Sebastian A1 - Zink, Markus H. A1 - Küchler, Andreas T1 - Experimental and simulative analysis of the thermal behavior of high voltage cable joints T2 - VDE-Hochspannungstechnik 2018, Berlin N2 - Nowadays, cable systems are often preferred when deciding on the type of new transmission lines even in the high and extra high voltage range. One of the main reasons is the better public acceptance. In addition, the power to be transmitted in the grid is increasing leading to increased ohmic losses and thus, to higher thermal stress on the materials. The investigations in this contribution focus on cable joints, which represent important and decisive components of cable systems. In order to optimize the design and to ensure reliable operation over the entire service life, the temperature profile within these components is of special interest. For their detailed investigation, a test circuit was set up consisting of a cable section and sections with build-up stages of a cable joint. A large number of measuring points were defined also at points where no measurement is possible in normal operation. With a thermographic camera the surface temperature distributions were observed. With the laboratory setup temperature profiles under various load conditions were recorded. A detailed FEM model was built and verified with help of these measurements. The model permits the investigation of specific questions of cable systems such as the comparison of temperature loads resulting from normal operating conditions and of test procedures according to the relevant standards. Besides others the effect of stressing the insulation and sealing system by heating the inner conductor vs. heating from outside by surrounding water is discussed. Y1 - 2018 UR - https://ieeexplore.ieee.org/document/8576752 ER - TY - JOUR A1 - Zink, Markus H. A1 - Klipfel, V. A1 - Berger, Frank A1 - Küchler, Andreas A1 - Voll, S. T1 - Der Einfluss von Temperatur und Streukapazität auf diagnostische Kapazitäts- und Verlustfaktormessungen von 400 kV-Hochspannungstransformatordurchführungen JF - ETG-Fachtagung „Diagnostik elektrischer Betriebsmittel“ Y1 - 2012 CY - Fulda ER - TY - CHAP A1 - Wirth, Isabell A1 - Heßdörfer, Nadja A1 - Küchler, Andreas A1 - Zink, Markus H. A1 - Langens, Achim A1 - Berger, Frank T1 - Measurements and calculations of critical thermal and electrical stress conditions for HVDC bushings T2 - 20th International Symposium on High Voltage Engineering, Buenos Aires, 2017 Y1 - 2017 ER - TY - CHAP A1 - Hopf, K. A1 - Wirth, Isabell A1 - Sturm, Sebastian A1 - Küchler, Andreas A1 - Zink, Markus H. A1 - Langens, Achim T1 - Temperature-dependent and anisotropic electrical conductivity of resin-impregnated paper T2 - Power and Energy Student Summit, Nürnberg, 2017 Y1 - 2017 ER - TY - CHAP A1 - Wirth, Isabell A1 - Küchler, Andreas A1 - Zink, Markus H. A1 - Berger, Frank A1 - Langens, Achim T1 - Elektrische Feldverteilung und Polarisationsströme in HGÜ Durchführungen T2 - Fachtagung Polymere Isolierstoffe und ihre Grenzflächen, Zittau, 2018 Y1 - 2018 ER -