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Research Of Bridge Type High-Tc Superconducting Fault Current Limiter

Posted on:2007-12-21Degree:DoctorType:Dissertation
Country:ChinaCandidate:Z F ZhangFull Text:PDF
GTID:1102360182499720Subject:Superconducting power technology
Abstract/Summary:PDF Full Text Request
Bridge type high-Tc superconducting fault current limiter (HTSFCL) is determined as the research object in this paper, in which the limiting principle is explored theoretically and kinds of circuit topologies of bridge type HTSFCL are established. A 3-phase bridge type HTSFCL prototype is designed in lab, by which short-circuit fault limiting experiments have been done successfully. The conclusions are as follows:Three kinds of topologies of bridge type HTSFCL— mutual-inductor type, LC resonance type and electric discharge type HTSFCL with different structures and different operation principles, have been designed, by which the operating principles are analyzed, and simulation models are established, and the main parameters are optimized.The control means of novel bridge type HTSFCL, namely resistor-assistant type HTSFCL, are presented, in which the controllable limiting element is not a superconducting coil, but a resistor. With different feedback currents or voltages, the control algorithm, such as single value relative control algorithm, hysteresis control algorithm and predicted relative control algorithm, are established to meet the demands of various volume HTSFCL. The further research is about the relationship between controllable regulation function and self-adjustment function of the HTSFCL.The HTSFCL prototype has been designed and manufactured both in hardware and software in our lab, which integrates the functions of both short-current fault triggering and fault limiting. The HTSFCL is composed of power electrical subsystem, detection subsystem, controller, high-Tc superconducting coils and cryogenic subsystem. As a result, the HTSFCL is more controllable and operable to use. Based on the designed parameters of the propotype, the design rationality has been confirmed by simulation results, which include the relationship between superconducting coil inductance and the THD of the line current, the relationship between the fault response time and the first peak of fault line current, and the relationship between the value of limiting resistor and the fault current in steady state.Experiments of the HTSFCL have been done successfully. A single fault limiting testing circuit is designed to validate the response capability of the HTSFCL to various short-current faults and shows that the HTSFCL can limitboth transient and steady-state fault current. An intermittent fault limiting testing circuit has shown the quick limiting performance to two-time intermittent fault, and also confirmed the auto-reclose function of the HTSFCL. The HTSFCL prototype has been used to in dynamic simulation experiments, in which the functions of limitation to various faults, cooperation with relay protective device and protection of power bus are all validated.
Keywords/Search Tags:high-Tc superconducting fault current limiter, rectifier, controller, power system, ARM, relay protection
PDF Full Text Request
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