基于STM32L051的 SF₆ 气体微水密度在线监测系统研究

打开文本图片集

关键词： SF6 气体；高精度电容式湿度传感器；在线监测；RS485通信

中图分类号：TM930.7 文献标志码：A 文章编号：1003-5168（2025）24-0017-05

DOI： 10.19968/j.cnki.hnkj.1003-5168.2025.24.003

Research on Online Monitoring System for Micro-Water Density of SF6 GasBasedonSTM32L051

LI Yongkai CAO Lingyan JIN Chengfeng ZHAO Haiping MAO Jiangfeng SHEN Yaoyu （Jiangsu Guodian Nanzi Haiji Technology Co.，Ltd.，Nanjing 2111Oo， China）

Abstract： [Purposes] SF6 gas serves as a crucial insulating medium for high-voltage electrical equipment.The real-time status of its moisture content and gas density directly affects the insulation performance and operational safety of the equipment.In large substations and GIS equipment clusters， when multiple compartments' SF6 gas chambers simultaneously experience excessive moisture or density reduction，traditional manual inspection methods suffer from delayed response and dificult location identification， which may lead to accelerated insulation deterioration and even discharge faults in the equipment.[Methods] High-precision capacitive humidity sensors are used to collect real-time signals of moisture concentration，gas density，and gas chamber temperature in the gas chambers.By utilizing the state parameter equation of the gas and through rapid numerical calculation methods，the measured pressure and temperature values are embedded online into the single-chip microcomputer. After processing through multi-stage signal conditioning circuits，the data is transmited to the main control unit via the

RS485 bus using the MODBUS-RTU protocol.[Findings] The system can accurately calculate the density value of the gas and the pressure value corrected to 20°C .By selecting the optimal fitting method for the sensor，results with precision better than that of table lookup by orders of magnitude can be obtained. [Conclusions] Inteligent diagnosis and early warning of equipment health status are successfully achieved in the background.After being applied in a certain power enterprise's station in Hainan， the system has been operating well，effectively preventing the occurrence of defect faults in GIS equipment clusters and ensuring the safe and reliable operation of the power system.

Keywords： SF6 gas; high-precision capacitive humidity sensor; online monitoring; RS485 communication

0 引言

SF6 （六氟化硫）气体作为高压断路器、GIS（气体绝缘开关设备）等电力装备中广泛使用的核心绝缘与灭弧介质，其微水含量及气体密度的稳定性直接决定了设备绝缘强度与运行寿命。（剩余5588字）