Current limiting devices: a new concept for improving power quality

This paper discusses the concept of a current limiting device (CLD) for use in electrical power distribution networks. The device itself is only a concept, therefore the intention here is to (1) introduce the concept, and (2) show how incorporation of such devices would affect network operations, and (3) show some of the benefits that could be derived via use of such a device. As faults in distribution systems (as opposed to HV/EHV networks) account for a large percentage of all power interruptions, it makes sense to examine possible improvements in distribution system design in order to improve power quality. In the future, advances in high power semiconductor materials and devices could make it feasible (cost effective) to incorporate more power electronic systems into distribution systems than is the case currently. This, in conjunction with the fact that costs for computing and communications systems are decreasing rapidly, opens the possibility of building distribution systems much more efficient than those used today. This paper examines issues associated with incorporating current limiting devices (CLDs) into electrical power distribution systems, examining how use of such devices would affect network operations, and on how such devices could be used to enhance power quality. The term `power quality´ encompasses many things such as voltage sags/swells, harmonic distortion, and flicker. The aspect of power quality this paper addresses is alleviating voltage sags experienced during the course of a fault