Temperature Control of a Pulse Tube Cryocooler System Using Model Identification and Dynamic Matrix Control

This paper discusses the temperature control problem of a pulse tube cryocooler system, precise modeling of the cryocooler system in analytic form can be difficult owing to the fact that its inherent complex mechanotronics and thermal feature. To overcome this, the relay feedback identification is applied on test bench to obtain the process model of the cryocooler and a high-order model is proposed and identified using least square fitting method with guaranteed conformity. Based on the step response data model, model predictive control is adopted to predict the system output and compensate for the error caused by model mismatch, which can achieve better control performance comparing with the PID control. Finally, the simulation and experimental results are provided to illustrate the effectiveness of the proposed method.