Review of power converters for wind energy systems

The paper presents commonly used power electronic topologies in Wind Energy Conversion Systems. It discusses the main differences between partially and fully rated converters, their control methods and their application in large and small scale wind turbines. The paper also presents methods of tracking the optimal power point for permanent magnet synchronous generator based wind energy systems.peer-reviewe

The centre cannot (always) hold:Examining pathways towards energy system de-centralisation

This is the final version. Available on open access from Elsevier via the DOI in this record'Energy decentralisation' means many things to many people. Among the confusion of definitions and practices that may be characterised as decentralisation, three broad causal narratives are commonly (implicitly or explicitly) invoked. These narratives imply that the process of decentralisation: i) will result in appropriate changes to rules and institutions, ii) will be more democratic and iii) is directly and causally linked to energy system decarbonisation. The principal aim of this paper is to critically examine these narratives. By conceptualising energy decentralisation as a distinct class of sociotechnical transition pathway, we present a comparative analysis of energy decentralisation in Cornwall, South West UK, the French island of Ushant and the National Electricity Market in Australia. We show that, while energy decentralisation is often strongly correlated with institutional change, increasing citizen agency in the energy system, and enhanced environmental performance, these trends cannot be assumed as given. Indeed, some decentralisation pathways may entrench incumbent actors' interests or block rapid decarbonisation. In particular, we show how institutional context is a key determinant of the link between energy decentralisation and normative goals such as democratisation and decarbonisation. While institutional theory suggests that changes in rules and institutions are often incremental and path-dependent, the dense legal and regulatory arrangements that develop around the electricity sector seem particularly resistant to adaptive change. Consequently, policymakers seeking to pursue normative goals such as democratisation or decarbonisation through energy decentralisation need to look beyond technology towards the rules, norms and laws that constitute the energy governance system.Engineering and Physical Sciences Research Council (EPSRC)European Structural and Investment FundINTERREG V FC

Stream monitoring manual /

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Critical trends assessment Program 2002 report

"July 2003"Includes bibliographic references.Introduction -- Creating a report card for RiverWatch stream quality: multi-metric biological score -- Multi-metric habitat score -- Aquatic insects report -- What are the discarded sites of CTAP terrestrial monitoring telling us about Illinois habitats? -- Ornithological report: The depauperate nature of the average Illinois bird community -- ForestWatch fall 2001-spring 2002 -- PrairieWatch 2001 and 2002 -- RiverWatch data summary results for 2002 -- Botanical report: Floristic quality assessment (FQA as a measure of the naturalness of the grasslands and wetlands of Illinois -- Terrestrial insect report: The importance of leafhoppers (Hemiptera: Cicadellidae) collected by the Critical Trends Assessment Program.Mode of access: Internet