An Innovative Shielding Strategy for Stray Loss Reduction of Neutral Grounding Reactor

Leakage fluxes formed by power equipment are one of the serious concerns of the electricity industry. Stray losses, which are a consequence of leakage fluxes, can lead to thermal stresses in metallic parts and dramatically reduce the life of the equipment. To alleviate this obstacle, this article aims to deploy a new approach to mitigate the stray losses in structural parts. This method is based on electric and magnetic shielding to deviate or bypass the stray fluxes and abstain from hot spots. Computation of stray losses inside the shields and other metallic structures is conducted using 3-D finite element analysis (FEA). To determine the dimensions of shields, various contingency simulations are implemented. A 0.51 MVAr, air-core, oil-immersed neutral grounding reactor (NGR) is considered as a case study to verify the effectiveness of the presented method. The performance of the suggested shield arrangement has been experimentally investigated, and the obtained results present an indication of a best-suited design with respect to performance and size.