A study of distributed energy resources and RF triggered high temperature superconductive current switch

With increasing demands in the electricity market; Distributed Energy Resources (DERs) are increasingly applied as supplementary and competitive alternatives to conventional large central power plants. This thesis explores new features of DERs and studies their operational impact on the performance of distribution systems. Novel measures for congestion relief and Load Elasticity (LE) improvement are presented, as well as a heuristic positioning strategy of Superconducting Magnetic Energy Storage (SMES) for voltage sag mitigation. A new RF triggered high temperature superconductive current switch is developed with a fast light load switching capability, which is fundamental for SMES.; Embedded in distribution systems, DERs are able to provide fast and reliable local load following services as supplementary power solutions to relieve congestion. AC power flow based sensitivity analysis is performed to quantify the impact of DERs on line flows and system voltage profiles with closed-form formulas. In addition, the system-wide trends of such an impact are classified by a fuzzy clustering approach. Two new robust distribution load flow algorithms, Ratio-flow and hybrid Distri-flow, are also proposed for ill-conditioned radial systems and complex distribution systems integrated with DERs respectively.; Based on the load characteristics and market price information, the improvement in LE with DERs during price spikes are studied. The operational impact of individual DERs on LE improvement in distribution systems is defined by a sensitivity analysis.; Power quality enhancement is another important new application of DERs. Based on the operational impact information, a heuristic positioning strategy of Micro-SMES for severe voltage sag mitigation in distribution systems is introduced. Simulation results show the applicability of the proposed method.; The Superconductive-Normal (S-N) current switch is one of the fundamental components of SN-lES. A new RF triggered High Temperature Superconductive (HTS) S-N switch with a 2.45GHz RF signal is developed in this research with the focus on a light load triggering capability. The experiment results of a 100ms S-N transition demonstrate that thin-film HTS materials are attractive solutions for RF triggered S-N switches.