Control of distributed generation

Abstract

Distributed generation (DG), whose installed capacity is increasing rapidly, can be defined as low rating generation that is neither planned nor dispatched centrally and is usually connected to the distribution network. Appropriate control of DG can improve the performance of DG units without violating network constraints, and facilitate the effective participation of DG in power system and market operation. Two control levels, DG unit control and network control, are summarized. DG unit control is introduced based on three technologies: induction generators, synchronous generators and power electric converters. Effective network control can be built based upon active management concept. Finally, three DG control paradigms, MicroGrid, cell and virtual power plant, are discussed. Steuerung der dezentralen Erzeugung. Dezentrale Erzeugung kann als Erzeugung geringerer Leistung bezeichnet werden, die an das Verteilnetz angeschlossen ist, jedoch ohne zentrale Planung und zentrale Einspeisung in das Netz auskommt. Eine geeignete Steuerung der dezentralen Erzeugung kann deren Leistung erheblich verbessern, ohne Netzbegrenzungen zu verletzen, und erleichtert damit eine erfolgreiche Beteiligung im Stromnetz und am Strommarkt. Im Folgenden werden zwei Steuerungsebenen -die Steuerung der einzelnen Einheiten dezentraler Erzeugung sowie die Netzsteuerung -vorgestellt. Erstere wird auf Basis von drei Technologien erlä utert: Induktionsgeneratoren, Synchrongeneratoren und Stromrichter. Eine wirkungsvolle Netzsteuerung kann anhand eines aktiven Managementkonzepts aufgebaut werden. Schließlich werden drei Beispiele fü r die Steuerung -MicroGrids, Speicherzelle und virtuelles Kraftwerk -besprochen. Schlü sselwö rter: dezentrale Erzeugung; Steuerung; MicroGrids; virtuelle Kraftwerke IntroductionDistributed generation (DG), according to the CIGRE WG 37-23 definition, is low rating generation that is neither planned nor dispatched centrally and is usually connected to the distribution network (CIGRE working group 1999). The range of DG includes, for example, wind turbines, small hydro turbines, CHP units, photovoltaic (PV) cells, fuel cells, and micro turbines. DG, energy storage and manageable loads are incorporated in the wider concept of distributed energy resources (DER). The installed capacity of DG is expected to continue increasing over the coming years (Pecas Lopes et al., 2007).Different control systems are being investigated in order to accommodate DG in the network. Those systems are to improve the performance of DG units without violating network constraints, and provide appropriate frameworks for them to participate effectively in the power system and market operation. Two different control levels have been identified, DG unit level and distribution network level. Moreover, a number of control paradigms are also being investigated in order to provide the required framework for the operation and management of DER.

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A survey on the contributions of power electronics to smart grid systems

“…The control environment, which contains switches, meters technical personnel, is now being managed owing to remote control and telemetry features of smart grid. To achieve this development, utility grid is equipped with remotely activated switches, automatic circuit breakers, and reclosers, which involve power electronics [38,57,[60][61][62].…”

Analysis of motor starting in a weak microgrid

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