As a critical insulating and connecting component in high-voltage power transmission and transformation systems
the manufacturing level of bushings directly impacts the safety and stability of the power grid as well as the efficiency of energy transmission
and represents a key technological link supporting dual-carbon goals through initiatives such as the West-to-East Power Transmission Project. This paper systematically reviews the current status and industrial challenges in the domestic manufacturing of four mainstream bushing products
namely
oil-impregnated paper bushing
SF₆ gas bushing
resin-impregnated paper bushing
and resin-impregnated fiber bushing
from following three perspectives: material systems
structural design and process control. The study reveals that oil-paper bushings feature mature technology and hold a market share of over 56% at voltage levels of 550 kV and below
yet they face challenges such as aging of oil-paper insulation and sealing leakage. SF₆ gas bushings lead internationally in ultra-high-voltage direct current(UHVDC) applications
though their high cost and the greenhouse effect of SF₆ limit environmental compatibility. Resin-impregnated paper bushings offer superior safety performance and are increasingly becoming the mainstream choice in ultra high voltage(UHV) projects and markets
yet they still rely on imported epoxy resin and crepe paper
with a relatively complex manufacturing process. Resin-impregnated fiber bushings
as a domestically developed technology
are gradually being applied in 550 kV and below AC projects
though the issue of space charge accumulation in DC applications remains unresolved. Driven by national strategic development
manufacturing technology of bushing has evolved from “catching up” to “running in parallel and leading in certain areas”. This study provides a systematic reference for the independent and high-end development of bushing manufacturing technology in China
supporting the construction of UHV power grids and new energy transmission networks.