Study on coal mine main fan automatic switchover aiming at ventilation unceasing and its numerical simulation

Ventilation interruption in high gas mine during main fan switchover in the way currently-used that working fan stops at first and standby fan starts later is liable to cause gas concentration exceeding limit. In the paper, a novel way to realize ventilation unceasing during main fan switchover is put forward, in which, contrary to the way currently-used, standby fan was required to be started before working fan stopped to obtain continuous ventilation power. In addition, a kind of sequence control strategy for air-doors regulation cooperatively was studied for subsequent ventilation network switchover. In order to find the optimal parameter coordination about delay time of sequence control, numerical simulations of the air flow rate and the equivalent ventilation resistance during main fan switchover were executed in MATLAB to check ventilation stable and main fan safety at the same time. Finally, according to which, an automatic control system had been developed and had achieved the perspective goal in its first operation.