Experimental Analysis of the Magnetic Flux Characteristics of Saturated Core Fault Current Limiters

Abstract

A fault current limiter (FCL) is a device that is designed to reduce the impact of fault currents on electricity networks and increase the availability of such networks to consumers. One particular FCL technology that is currently attracting worldwide attention, from both researchers and commercial engineering companies, is the saturated core FCL. This device utilizes the change in permeability between the saturated and unsaturated states of a magnetic core to provide both low steady state losses and effective fault current limiting. Typically the core is saturated using an electromagnetic coil, which can be either superconducting or nonsuperconducting. Although there have been several studies on the electrical characteristics of this device, the transient magnetic behavior has been largely overlooked. In this paper the magnetic flux characteristics of saturated core FCLs are experimentally analyzed. The study includes the magnetic behavior during both the initial biasing of the cores and during transient fault conditions. The influence of FCL topology and alternative low-cost core materials, on the flux characteristics and overall device performance, is also discussed. © 1965-2012 IEEE. Abstract-A Fault Current Limiter (FCL) is a device that is designed to reduce the impact of fault currents on electricity networks and increase the availability of such networks to consumers. One particular FCL technology that is currently attracting worldwide attention, from both researchers and commercial engineering companies, is the saturated core FCL. This device utilizes the change in permeability between the saturated and unsaturated states of a magnetic core to provide both low steady state losses and effective fault current limiting. Typically the core is saturated using an electromagnetic coil, which can be either superconducting or nonsuperconducting. Although there have been several studies on the electrical characteristics of this device, the transient magnetic behavior has been largely overlooked. In this paper the magnetic flux characteristics of saturated core FCLs are experimentally analyzed. The study includes the magnetic behavior during both the initial biasing of the cores and during transient fault conditions. The influence of FCL topology and alternative low-cost core materials, on the flux characteristics and overall device performance, is also discussed.

Application of saturated core fault current limiters to interconnected distribution networks

“…A number of studies on the subject of saturated core FCLs, ranging from operational behaviour, material aspects, core designs, prototypes and testing, have been reported in the literature [6]- [8]. The saturated core FCL, essentially utilises the dynamic and nonlinear magnetic behaviour of steel cores to operate as a variable inductance reactor.…”

“…Hence, the fault impedance of an FCL is typically defined as the equivalent steady-state impedance that would result in the same fault current limiting effect [6]. Based on this definition the fault impedance of the FCL device in Section III-B can be estimated to be, Z F CL = 0.267Ω.…”

Investigation of the performance of SISFCL with the variation of hysteretic characteristics

“…3, demonstrates that the variation in hysteresis loop has negligible effect on the current in normal operation, although the effect is highly noticeable during fault. During normal operation the limiter presents low impedance close to twice the value of an air core inductor [18] maintaining a 30 A current even in the presence of FCL. The model in designed to simulate its working for a prospective current of about 3.6 kA peak.…”

A Novel Bridge-Type Hybrid Saturated-Core Fault Current Limiter Based on Permanent Magnets

“…This unique feature of the BHFCL leads to fewer coils and lower energy losses. were proposed and analyzed in [5]- [10]. However, the optimization of configuration is beyond the research scope of this paper.…”