Fuzzy-PI algorithm for manned module thermal control

A new control scheme based on a Fuzzy-PI algorithm was presented to control the temperature control and check valve (TCCV) in a condensing heat exchanger (CHX) in manned module. There is a control threshold switching between PI and Fuzzy control. When the absolute error is higher than the threshold fuzzy control is used, otherwise PI control is used. The algorithm uses instantaneous and longer-term changes in measured temperature to continually adjust the TCCV position and maintain the atmospheric temperature within specified limits. Simulation was conducted, and results showed that the proposed control scheme made it possible to improve temperature stability and control precision.