Hv shunt reactors: an overall comparative analysis between dry-type air core and oil-immersed iron core technologies

Abstract

Shunt reactors in high-voltage and extra high-voltage, have historically been manufactured using oil-immersed iron core technology, mainly due to issues related to the insulation of the reactor windings. However, with the improvement of the insulating films as well as on the manufacturing techniques, it has been possible the manufacturing of these equipment using dry-type air core technology, which has demonstrated to be efficient, environmentally friendly and, in many cases, with lower costs in short, medium and long-term basis. It is required therefore, the study of which are the changes when it is adopted this air core technology, which has been the more and more accepted on worldwide market. The main aspects regarding the application of these equipment are disclosed, stablishing a parallel between both technologies, with regards to the construction aspects, the viability of replacement (which are the cases at which they are or not indicated), the losses comparison, all the precautions and remarks in terms of magnetic field, the protection and the transients aspects (including a study case of two identical equipment in both technologies, with calculations and simulations of transient frequency and voltage, TRV and RRRV, as well as a percentage comparative analysis between the calculated and simulated results). These comparisons, aim to contribute with technical community and the global trend in adopting dry-type technology, highlighting the main differences and particularities to be considered when replacing traditional type.