Sensor optimization based on simulation of EMI distribution in underground working coal face

In the process of mining, the sensor is very important for mining safety to monitor gas concentration. With increasing of electronic equipments in coal mine, the electromagnetic interference becomes serious now. There were false alarms of sensors under harsh EMI environment. Therefore the interference immunity of the sensor becomes very important. In order to clear up false alarms, caused by Electromagnetic Interference (EMI), a novel field way was brought forward in which the simulation and radiated emission measurement were adopted to accomplish the analysis of shielding property about methane sensor. The simulation software HFSS of Ansoft company was adopted. The data was acquired through the R&S spectrum analyzer FSP7. With analyzing the influence of cable aperture on enclosure shielding properties through simulation and measurement, the optimization of explosion-proof enclosure was finished according to the distribution of radiated interference characteristics and simulation of the trumpet structure shield performance. The running results demonstrated that the problem of false alarms had been resolved successfully with the optimization of explosion-proof enclosure. It is concluded that the improved shielding and filtering are highly significant in enhancing the Electromagnetic Compatibility (EMC) of the methane sensor.