A high precision temperature control strategy for space refrigeration controller

Abstract

With the appearance of high-power focal plane module, in order to meet the refrigeration demand of infrared optical remote sensing load under complex working conditions, it is necessary for space refrigeration controller to have high-precision temperature control effect. For the sake of improving the temperature control accuracy of traditional space refrigeration controller, a high-precision temperature control strategy is proposed. By designing a temperature measurement circuit with secondary amplification and low-pass filtering mechanism, high-precision temperature measurement data can be obtained as the temperature feedback input source of the system. Through experimental test, the static temperature measurement accuracy can be improved from 20mk to 5.4 mk by the secondary amplification and low-pass filtering module. By designing the incremental PID with limiting amplitude and speed, the algorithm realizes the fast convergence of temperature curve and small overshoot. The experimental results show that the temperature control accuracy of the high-precision refrigeration controller is ±0.025k, and it stabilizes within 7 minutes after being disturbed, thus realizing high-precision and high-stability refrigeration control.