Real-time fault early warning system and method for high-altitude simulation test of liquid attitude and orbit control engine

The invention relates to a real-time fault early warning system and method for a high-altitude simulation test of a liquid attitude and orbit control engine, and aims to solve the technical problems of low personnel response speed, long operation time and high possibility of serious accidents in the process of manually monitoring system parameter change of a water vapor generator and manually and emergently shutting down. The system comprises a real-time monitoring module, an abnormity diagnosis module and a fault early warning module, wherein the real-time monitoring module comprises a real-time data acquisition unit and a plurality of measurement sensors. The method comprises the following steps: 1, obtaining classifiers of all operation stages, and starting a water vapor generator system; 2, acquiring parameter set data at the current moment; 3, calculating credibility, and if the credibility is greater than a credibility threshold, continuing monitoring; and if the credibility is smaller than or equal to