Overall design of JX-300 XP DCS control system developed by SUPCON was introduced, including the hardware part and software part. Combined with characteristics of Huadian oil shale retorting process furnace combustion system including multi variable, strong coupling, strong interference and large lag, the cascade fuzzy control of gas pressure-temperature in the furnace was designed by method of fuzzy control and self optimizing, the control strategy to simultaneously optimize the oxygen content and the furn...