This Master of Applied Science thesis presents an inverter control system design and implementation with active damping of LCL filter resonance for a single phase grid-connected Distributed Power Generation (DPGS). The focus of the thesis is to actively damp the LCL filter resonance while keeping inverter control variables well regulated. The mathematical model of the LCL filter is analyzed and the filter is designed. Then, a PLL, and a PI compensator in the synchronous reference frame, and a PR compensator in stationary reference frame along a notch filter in cascade are designed and implemented. System level simulation and implementation are conducted. The idea of systematic applying the low loss power conversion topology, effective grid condition detection, grid synchronization, and advanced signal processing theory provides some advantages for single phase grid-connected inverter control design to meet the standard specifications of the interaction between the DPGS and utility grid. / Thesis (Master, Electrical & Computer Engineering) -- Queen's University, 2014-06-26 17:06:03.693

This study analysed the strategies of selected National Governing Bodies (NGBs) and voluntary sport clubs (VSCs) in the process of policy implementation of Sport England s generic Clubmark (a quality mark accreditation framework). Within the overarching Clubmark framework, other policies (safeguarding and increasing membership and/or participation) adopted by VSCs working towards the accreditation (or re-accreditation) standard were also examined. Policy-makers are predominantly centrally located, often a distance from the point of delivery where, it is argued; the environment is highly variable, pressured and political, often requiring negotiation and interpretation during the process of implementation. Traditionally, implementation analysis assumed two distinct approaches: top-down theorists (e.g. Hogwood & Gunn, 1984) suppose a perfect rational, systematic process as the starting point, with the focus placed on central policy-makers. The top-down theorists acknowledge that the ideal is unattainable but use the perspective to establish generalisable descriptive policy advice; in contrast, bottom-up theorists (e.g. Lipsky, 1980) argued that to gain a more realistic understanding of implementation the role of street-level bureaucrats (e.g. VSC members at the point of delivery) should be the focus for analysis and seek to offer prescriptive advice. More recently, a number of theorists have developed hybrid implementation models, which offered a synthesis of the two contrasting approaches, such as Matland's (1995) Ambiguity-Conflict model. The combination of these three approaches coupled with Kingdon's (1997) Multiple Streams framework, used to help organise and set a context for the understanding of implementation during analysis, established the theoretical framework that guided this study. The research adopted a qualitative approach using case studies for the three sports of boxing, swimming and rugby union. Data collection consisted of 29 semi-structured interviews from VSC members, NGB officials, a senior Sport England official and a County Sports Partnership officer. The interview data were combined with document analysis (from VSCs, NGBs and Sport England), which included policy documents, guidance templates, electronic communications and various website content. Two clubs from each sport were examined (one urban, one rural). VSC member selection was based on positions of authority within the committee who had some prior knowledge of Clubmark. Three to four NGB officials from each sport provided data for the top-down perspective of policy implementation. Analysis of the data revealed that policy implementation is not straightforward; NGBs had to be flexible with their strategies and be willing to modify criteria to deal with the varying nature and capacities of VSCs. Available NGB capacity to offer VSC support proved to be pivotal for implementation success in addition to the ability of the NGBs recognising the range of contextual constraints, which limited VSCs in the implementation process. At the club-level, motivation and willingness of VSC compliance for the three main policy strands varied across sports and clubs, which demonstrated how the role of the VSC members, as implementing agents, was fundamental in the policy process. At the NGB-level, the urgency or importance placed on the three policies and the variable capacity (to offer support) affected implementation. Application of the theoretical framework that guided the research proved effective in developing the understanding of implementation in this particular sport context. Furthermore, this research has provided a contribution to the literature by demonstrating how the complex and heterogeneous nature of VSCs affects the implementation process in community sport, which provides a useful point of reference for future comparative studies analysing NGBs and VSCs in different contexts.

This study covers the sliding mode control design for a class of nonlinear systems, where the control input affects the state of the system linearly as described by (d/dt)x=A(x)x+B(x)u+d(x). The main streamline of the study is the sliding surface design for the system. Since there is no systematic way of designing sliding surfaces for nonlinear systems, a moving sliding surface is designed such that its parameters are determined in an adaptive manner to cope with the nonlinearities of the system. This adaptive manner includes only the automatic adaptation of the sliding surface by determining its parameters by means of solving the State Dependent Riccati Equations (SDRE) online during the control process. The two methods developed in this study: SDRE combined sliding control and the pure SDRE with bias terms are applied to a longitudinal model of a generic hypersonic air vehicle to compare the results.