TY - GEN A1 - Sweelem, Emar A. A1 - Farouk, M. A1 - Lappus, Gerhard A1 - Nafeh, Abd El-Shafy A. A1 - Dohra, Hassan T1 - Fuzzy logic operation control for PV-Wind-Diesel-Battery hybrid energy systems T2 - International journal of renewable energy engineering KW - Wind KW - Diesel KW - Energy-systems KW - FUZZY Y1 - 2002 SN - 1442-133X VL - 4 IS - 2 ER - TY - CHAP A1 - Noureldin, Amer Abdelfattah Ali A1 - Lappus, Gerhard T1 - Advanced control in freelance 2000 with online interface to Matlab/Simulink T1 - Gehobene Regelung mit dem Prozessleitsystem Freelance 2000 unter Verwendung einer Online-Schnittstelle zu den Programmen Matlab und Simulink T2 - Conference proceedings, the 4th Asian Control Conference, September 25 - 27, 2002, Singapore KW - Matlab KW - Simulink KW - Freelance Y1 - 2002 SN - 981-046440-1 SP - 1400 EP - 1405 CY - Singapore ER - TY - JOUR A1 - Lappus, Gerhard A1 - Weinmann, Andreas T1 - Dynamische Gasnetzsimulation im Lichte der Öffnung der Energiemärkte JF - Gas- und Wasserfach: Gas – Erdgas Y1 - 2001 SN - 0016-4909 VL - 142 IS - 8 SP - 560 EP - 562 ER - TY - CHAP A1 - Handreg, Martin T1 - Neuronale prädikative Regelung von Prozessgrößen in Flachglasschmelzwannen T2 - 50. Regeltechnisches Kolloquium, Boppard, 2016 KW - Regelungstechnik, Boppard Y1 - 2016 UR - http://www.iosb.fraunhofer.de/servlet/is/60094/Boppard%202016%20-%20Vortrag%20Handreg.pdf ER - TY - CHAP A1 - Lappus, Gerhard A1 - Pöhtig, T. T1 - Non-Ggyroscopic North Finding System T2 - Symposium Gyro Technology 2008, Karlsruhe, Germany, September 16/17, 2008 Y1 - 2008 SP - 19 PB - Inst. für Theoretische Elektrotechnik und Systemoptimierung CY - Karlsruhe ER - TY - CHAP A1 - Schmuck, J. A1 - Lappus, Gerhard ED - Hohmann, Rüdiger T1 - Simulative Entwicklung einer Regelung für eine komplexe zirkulierende Druckwirbelschichtfeuerung T2 - Simulationstechnik, 17. Symposium in Magdeburg, September 2003, ASIM 2003 Y1 - 2003 SN - 3-936150-27-3 SP - 255 EP - 260 PB - SCS-European Publ. House CY - Delft [u.a.] ER - TY - CHAP A1 - Martin, M. A1 - Lappus, Gerhard T1 - Leitsystemgekoppeltes Telepräsenzsystem T2 - Automation und Information in Wirtschaft und Gesellschaft, GMA-Kongress 2003, Kongress Baden-Baden, 3. und 4. Juni 2003 Y1 - 2003 SN - 3-18-091756-3 SP - 577 EP - 584 PB - VDI-Verlag CY - Düsseldorf ER - TY - THES A1 - Pöthig, Tom T1 - Genauigkeitsanalyse eines kreisellosen Nordsuchers Y1 - 2011 SN - 978-3-18-519508-2 PB - VDI-Verlag CY - Düsseldorf ER - TY - THES A1 - Noureldin, Amer Abdelfattah Ali T1 - Process identification and control using neural networks and fuzzy logic Y1 - 2003 PB - Brandenburgische Techn. Univ. CY - Cottbus ER - TY - THES A1 - Schmidt, Hans-Werner T1 - Unscharfe Informationen bei der Realisierung leittechnischer Anlagen Y1 - 1998 SN - 3-89653-361-4 PB - Mainz CY - Aachen ET - 1. Auflage ER - TY - RPRT A1 - Handreg, Martin T1 - Entwurf neuronaler Netze zur Prädikation von Prozessgrößen in einer Schmelzwanne für Floatglas Y1 - 2016 UR - http://www.hvg-dgg.de/download/hvg-mitteilungen.html SP - 2168-1 EP - 2168-10 PB - HVG CY - Offenbach ER - TY - RPRT A1 - Handreg, Martin T1 - Entwurf neuronaler Netze zur Prädikation von Prozessgrößen in einer Schmelzwanne für Floatglas - Teil 2 Y1 - 2016 UR - http://www.hvg-dgg.de/download/hvg-mitteilungen.html SP - 2170-1 EP - 2170-10 PB - HVG CY - Offenbach ER - TY - BOOK A1 - Ahmed, Tanveer T1 - Modeling the Renewable Energy Transition in Canada : Techno-economic Assessments for Energy Management KW - Energy Transition in Canada Y1 - 2016 SN - 978-3-319-31503-4 U6 - https://doi.org/10.1007/978-3-319-31505-8 PB - Springer International Publishing CY - Cham ER - TY - GEN A1 - Schiffer, Johannes A1 - Alghamdi, Sultan A1 - Fridman, Emilia T1 - Distributed Secondary Frequency Control Design for Microgrids: Trading off L2-Gain Performance and Communication Efforts under Time-Varying Delays T2 - 2018 European Control Conference, (EEC) 12-15 Jun 2018, Limassol, Cyprus KW - Microgrids Y1 - 2018 UR - eprints.whiterose.ac.uk/128268/1/DAI_design_ecc18_final.pdf SN - 978-3-9524-2698-2 PB - IEEE CY - Piscataway, NJ ER - TY - GEN A1 - Zonetti, Daniele A1 - Ortega, Romeo A1 - Schiffer, Johannes T1 - A Tool for Stability and Power Sharing Analysis of a Generalized Class of Droop Controllers for High-Voltage Direct-Current Transmission Systems T2 - IEEE Transactions on Control of Network Systems N2 - The problem of primary control of high-voltage direct-current transmission systems is addressed in this paper, which contains four main contributions. First, a new nonlinear, more realistic model for the system suitable for primary control design, which takes into account nonlinearities introduced by conventional inner controllers, is proposed. Second, necessary conditions-dependent on some free controller tuning parameters-for the existence of equilibria is determined. Third, additional (necessary) conditions are formulated for these equilibria to satisfy the power-sharing constraints. Fourth, establish conditions for the stability of a given equilibrium point. The usefulness of the theoretical results is illustrated via numerical calculations on a four-terminal example. Y1 - 2018 U6 - https://doi.org/10.1109/TCNS.2017.2687080 SN - 2325-5870 VL - 5 IS - 3 SP - 1110 EP - 1119 ER - TY - GEN A1 - Schiffer, Johannes A1 - Barabanov, Nikita A1 - Ortega, Romeo A1 - Efimov, Denis T1 - Conditions for Almost Global Attractivity of a Synchronous Generator Connected to an Infinite Bus T2 - Transactions on Automatic Control N2 - Conditions for existence and global attractivity of the equilibria of a realistic model of a synchronous generator with constant field current connected to an infinite bus are derived. First, necessary and sufficient conditions for existence and uniqueness of equilibrium points are provided. Then, sufficient conditions for local asymptotic stability and almost global attractivity of one of these equilibria are given. The analysis is carried out by employing a new Lyapunov-like function to establish convergence of bounded trajectories, while the latter is proven using the powerful theoretical framework of cell structures pioneered by Leonov and Noldus. The efficiency of the derived sufficient conditions is illustrated via extensive numerical experiments based on two benchmark examples taken from the literature. Y1 - 2017 UR - https://ieeexplore.ieee.org/document/7858643 U6 - https://doi.org/10.1109/TAC.2017.2671026 SN - 1558-2523 SN - 0018-9286 VL - 62 IS - 10 SP - 4905 EP - 4916 ER - TY - GEN A1 - Schiffer, Johannes A1 - Efimov, Denis A1 - Ortega, Romeo A1 - Barabanov, Nikita T1 - An Input-to-State Stability Approach to Verify Almost Global Stability of a Synchronous-Machine-Infinite-Bus System T2 - Philosophical transactions of the Royal Society. Series A, Mathematical, physical and engineering sciences N2 - Conditions for almost global stability of an operating point of a realistic model of a synchronous generator with constant field current connected to an infinite bus are derived. The analysis is conducted by employing the recently proposed concept of input-to-state stability (ISS)–Leonov functions, which is an extension of the powerful cell structure principle developed by Leonov and Noldus to the ISS framework. Compared with the original ideas of Leonov and Noldus, the ISS–Leonov approach has the advantage of providing additional robustness guarantees. The efficiency of the derived sufficient conditions is illustrated via numerical experiments. Y1 - 2017 U6 - https://doi.org/10.1098/rsta.2016.0304 SN - 1364-503X SN - 1471-2962 VL - 375 IS - 2100 ER - TY - GEN A1 - Schiffer, Johannes A1 - Dörfler, Florian A1 - Fridman, Emilia T1 - Robustness of Distributed Averaging Control in Power Systems: Time Delays & Dynamic Communication Topology T2 - Automatica N2 - Distributed averaging-based integral (DAI) controllers are becoming increasingly popular in power system applications. The literature has thus far primarily focused on disturbance rejection, steady-state optimality and adaption to complex physical system models without considering uncertainties on the cyber and communication layer nor their effect on robustness and performance. In this paper, we derive sufficient delay-dependent conditions for robust stability of a secondary-frequency-DAI-controlled power system with respect to heterogeneous communication delays, link failures and packet losses. Our analysis takes into account both constant as well as fast-varying delays, and it is based on a common strictly decreasing Lyapunov–Krasovskii functional. The conditions illustrate an inherent trade-off between robustness and performance of DAI controllers. The effectiveness and tightness of our stability certificates are illustrated via a numerical example based on Kundur’s four-machine-two-area test system. Y1 - 2017 UR - https://www.sciencedirect.com/science/article/pii/S0005109817301140?via%3Dihub U6 - https://doi.org/10.1016/j.automatica.2017.02.040 SN - 0005-1098 VL - 80 SP - 261 EP - 271 ER - TY - GEN A1 - Schiffer, Johannes A1 - Hans, Christian A. A1 - Kral, Thomas A1 - Ortega, Romeo A1 - Raisch, Jörg T1 - Modelling, Analysis and Experimental Validation of Clock Drift Effects in Low-Inertia Power Systems T2 - IEEE Transactions on Industrial Electronics N2 - Clock drift in digital controllers is of great relevance in many applications. Since almost all real clocks exhibit drifts, this applies in particular to networks composed of several individual units, each of which being operated with its individual clock. In the present paper, we demonstrate via extensive experiments on a microgrid in the megawatt range that clock drifts may impair frequency synchronization in low-inertia power systems. The experiments also show that-in the absence of a common clock-the standard model of an inverter as an ideal voltage source does not capture this phenomenon. As a consequence, we derive a suitably modified model of an inverter-interfaced unit that incorporates the phenomenon of clock drifts. By using the derived model, we investigate the effects of clock drifts on the performance of droop-controlled grid-forming inverters with regard to frequency synchronization and active power sharing. The modeling and analysis is validated via extensive experiments on a microgrid in the megawatt range. Y1 - 2017 UR - https://ieeexplore.ieee.org/document/7781662 U6 - https://doi.org/10.1109/TIE.2016.2638805 SN - 1557-9948 SN - 0278-0046 VL - 64 IS - 7 SP - 5942 EP - 5951 ER - TY - GEN A1 - Schiffer, Johannes A1 - Efimov, Denis A1 - Barabanov, Nikita A1 - Ortega, Romeo T1 - Relaxing the Conditions of ISS for Multistable Periodic Systems T2 - IFAC-PapersOnLine N2 - The input-to-state stability property of nonlinear dynamical systems with multiple invariant solutions is analyzed under the assumption that the system equations are periodic with respect to certain state variables. It is shown that stability can be concluded via a sign-indefinite function, which explicitly takes the systems' periodicity into account. The presented approach leverages some of the difficulties encountered in the analysis of periodic systems via positive definite Lyapunov functions proposed in Angeli and Efimov (2013, 2015). The new result is established based on the framework of cell structure introduced in Leonov (1974) and illustrated via the global analysis of a nonlinear pendulum with a constant persistent input. Y1 - 2017 UR - https://hal.inria.fr/hal-01508766 U6 - https://doi.org/10.1016/j.ifacol.2017.08.1365 VL - 50 IS - 1 SP - 7217 EP - 7222 ER -