A Compact High-Pressure Test Vessel with Standard GIS and Transformer Accessories for Examinations of Synthetic Air as an Alternative Insulating Gas
Year: 2026
Type: conference-paper
Abstract: Synthetic air is becoming increasingly important as a substitute for high global warming potential gases, especially sulfur hexafluoride$\left(\text{S F}_{\mathrm{6}}\right)$, in gas-insulated switchgears (GIS) and instrument transformers. With a zero global warming potential (GWP), it is among the most sustainable insulating gases; however, it exhibits different material behavior and properties compared to well-examined SF${ }_{6}$. Therefore, new design criteria based on experimental testing with synthetic air must be developed. In this context, this paper presents the design of a compact high-pressure test vessel that enables experimental investigations under AC and LI stress in synthetic air as well as other alternative gases. First, the requirements of the test vessel are presented and a design is proposed that is primarily based on numerous finite element method (FEM) simulations. Regarding the choice of components, standard components from GIS and transformer technology are used, to provide a practical and reproducible test environment. This also ensures the possibility of upgrading to higher voltage levels and the test vessel's general adaptability. The test vessel is designed to operate at gas pressures up to 1.5 MPa (abs.). The electrical qualification is conducted with respect to AC withstand voltage, LI withstand voltage and partial discharge inception and extinction at AC-voltages, providing a sufficient operating range for examinations on synthetic air. Furthermore, the determined AC breakdown voltages correspond exactly with IEC 60052 proving low influence and interactions of the test vessel environment on the investigated insulating gas.
Institution: Jade Hochschule
Language: English
Subfield: Electrical and Electronic Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: hybrid
OpenAlex ID: W7202343774