Automatic temperature control system for ultra-low temperature special optical monitoring equipment

Ultra-low temperature special optical monitoring equipment for a new generation of launch vehicle first-stage liquid oxygen fuel tank interior, liquid oxygen fuel tank inside the -183℃ ultra-low temperature environment, the reliable operation of the optical monitoring equipment has brought great challenges. Based on this, this paper designs an automatic temperature control system for ultra-low-temperature special optical monitoring equipment, the temperature measurement module uses DS18B20 circuit and is calibrated by PT100; the temperature control module is designed based on the heating film driving circuit of LM3406; on the basis of incremental PID control, combined with the fuzzy control, it designs the fuzzy incremental PID temperature control based on FPGA; and it realizes and tests hardware and software to the measurement and control temperature. Hardware and software implementation and testing, the realization of the 10-channel temperature measurement and 16-channel automatic temperature control; improve the PID algorithm can achieve dynamic temperature control, leaving the system heat margin, under the conditions of limited resources, to avoid power wastage, so that the monitoring equipment can run for a long time; has been successfully applied to the liquid oxygen environment, so that the internal components of the device can be in the near -180℃ to maintain the operating temperature of 20℃ or so, can be extended to other equipment equivalent to low temperature environment automatic temperature control.