In order to protect the safety of LNG carrier, onboard equipment, and personnel, it is necessary to monitor the liquid level, temperature, and pressure of LNG carrier. In case of emergency, the carrier side and shore side equipment should be turned off and alarmed. Therefore, this article designs a LNG carrier safety monitoring system. Firstly, the overall architecture of the system was designed, consisting of a management layer, a control layer, and a device layer; subsequently, its control functions were designed, including ESD emergency shutdown trigger/reset, cargo tank protection, sea/port mode switching, ESD testing control, ESD shielding control, and override control; then, based on the algorithm configuration software and graphic editing configuration software of Hollysys MACS V6.5 system, the control program was written and the human-machine interface was drawn; secondly, a functional test platform is built to test the functions of the system. The results show that the system can control each state of the LNG ship, monitor each parameter in real time, and perform emergency shutdown in emergency situations. Finally, due to the overload operation of the output equipment for a long time, in order to prevent the failure of the output equipment and lead to major accidents, this paper proposes a fault prediction based on BP neural network, so as to achieve accurate fault prediction and ensure the safe operation of LNG ships.
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