The intelligent controller of filling liquid nitrogen based on the grey prediction theory

Liquid nitrogen Dewar vessel is one of the important equipment in low-temperature refrigeration system. Because there are characteristics as time-varying parameters and serious disturbance by load in the process of filling liquid nitrogen, the controller using conventional control algorithm can not satisfy quality of controlling requirements. The article offers an intelligent control-algorithm of auto-filling liquid nitrogen based on the grey prediction theory, which has been used to design the intelligent controller of filling liquid nitrogen. The controller has been used successfully in the refrigeration system of Large Sky Area Multi-Object Fiber Spectroscopy Telescope (LAMOST), achieved satisfactory control effect.