Latest Practices of Eco-Friendly Clean Air High Voltage Switchgear Products

This article provides insights into the latest practices of Siemens Energy ${}^{\prime}\mathrm{s}$ eco-friendly Blue switchgear products. Furthermore, operational experience to date globally and in China will be presented. Some research, development, and additional tests have been done to ensure that products are of high quality, efficiency, and reliability. Clean air specification is given, and different product development status is summarized. Some of the research on X-ray radiation and its protection, verifying the integrity of vacuum interrupters, and special applications are explained in detail. Additional reliability tests, like tightness test with helium vs. $\text{SF}_{6}$, sea freight test with rated filling pressure, vibration test, and seismic test, are also presented and discussed. In the end, high expectations are provided for vacuum switching technology to be applicable to high voltage levels above 145kV.