基于物联网的开关柜内凝露形成及除湿研究

Formation mechanism and countermeasures of dewing in the metal enclosed switch cabinet based on internet of things

针对由金属封闭开关柜内露水凝结导致开关柜爆炸的安全事故问题,通过采用基于Zigbee和GPRS技术的多路温湿度在线采集系统,在阴晴交替的天气条件下,对耐火泥破损程度不同的金属封闭开关柜内的温湿度分布进行了实时监测,并利用相关性检测对开关柜内不同位置的湿度数据进行了分析,同时结合流体力学计算软件FLUENT对不同除湿措施条件下金属封闭开关柜内的湿度场进行了仿真,对金属封闭开关柜内凝露形成机理及现有的除湿措施的效果进行了一个深入细致的研究。研究结果表明,金属封闭开关柜内的湿气主要来源于电缆沟,由于柜底的湿气难以从柜顶的天窗散发,且加热器放置于柜底部时除湿效果较好,因此提出采用在开关柜底部安装除湿装置、增加通风装置以及做好电缆沟的密封的除凝露对策。

Aiming at the problems of explosion accidents in closed metal switch cabinets due to the condensation of water vapour under high pressure, an online multiplex temperature and humidity collection system based on Zigbee and GPRS was developed, by which real time mo-nitoring of humidity distribution in a switch cabinet in non-operation state under different kinds of circumstances could be implemented in dif-ferent weather. Real time data in different place of switch cabinets was analyzed by correlation detection. And with the assistance of FLUENT simulation, principle about dew condensation in a switch cabinet was investigated. The results indicate that moisture mostly comes from cable trench. For the reason that moisture in the bottom can hardly be evaporated form the skylight and the heaters placed in the bottom have great performance, suggestions that installing a dehumidifier and a ventilation device in the bottom of a switch cabinet, as well as ensuring the seal of cable trench to eliminate moisture and dewing are supplied.