针对现有瓦斯传感器测量精度低、损耗高、不具备本质安全特性的问题,设计了基于故障电流监测的瓦斯传感器。首先以传热学的基本理论为依据,明确瓦斯与空气的导热系数关系,分析瓦斯传感器的测量原理;分别对瓦斯传感器的硬件部分和软件部分进行设计;在此基础上,设计了瓦斯传感器本安保护电路,包括故障电流变化率检测电路、自恢复与驱动电路和软启动电路;最后将瓦斯传感器应用于实际工程,验证采集性能和本质安全性能。测试结果表明:瓦斯传感器在不同瓦斯浓度下都实现了较高的测量精度,误差控制在±0.3%以下,满足工作面巷道的工作需求;瓦斯传感器具有较强的本质安全性能,发生故障后实现快速保护,故障所产生的能量输出为65μJ,满足井下对本质安全电路的要求。

This research addresses the issues of low measurement accuracy, high loss, and lack of essential safety characteristics in existing gas sensors by presenting a gas sensor design based on fault current monitoring. The design process involves defining the relationship between the thermal conductivity of gas and air using basic heat transfer theory, and analyzing the measurement principle of the gas sensor. The hardware and software components of the gas sensor are meticulously designed. An intrinsic safety protection circuit is incorporated, featuring a fault current change rate detection circuit, self - recovery and drive circuit, and soft start circuit. The practical application of the gas sensor is demonstrated through its use in a project to verify its collection and intrinsic safety performance. The test results show that the gas sensor can achieve high precision measurement under different gas concentrations, with an error rate controlled below ±0. 3%, meeting the working requirements of the working face roadway. The gas sensor exhibits robust intrinsic safety performance, enabling rapid protection after failure. The energy output generated by the fault is μJ, meeting the requirements of the intrinsic safety circuit in the well.