Failure Mechanism and Improvement Measures of Fireproof Sealing in Valve Hall of UHV Converter Station

This paper compared and analyzed the current standards for fireproof sealing of valve hall in UHV converter station. It was found that the explosion effect was not taken into account in the design of fireproof sealing according to the current specifications. At the same time, the existing fire resistance test of valve hall was based on the standard temperature rise curve (wood stack fire), which cannot deal with the hot oil fire accompanied by explosion and high temperature in UHV converter transformer. Two modes of fire prevention and sealing failure of valve hall were proposed. On this basis, an improved design scheme including anti-explosion door and plugging fire prevention strengthening was proposed, and its effectiveness was verified by detonation impact simulation test. Finally, the evaluation system of UHV converter station valve hall fireproof sealing was proposed, including explosion resistance, fire resistance, fire weather resistance, electromagnetic shielding performance and mechanical properties.