电机调相式大功率脉管制冷机研究

Study on High-Power Pulse Tube Cryocooler With Linear Motor Type Phase Adjuster

脉管制冷机出口阻抗对于脉管制冷机性能有着至关重要的影响。本文利用直线电机作为调相机构,通过调节电机外接负载调节制冷机出口阻抗,同时调相用直线电机回收制冷机出口膨胀功,转化成电能进行回收。基于经典热声理论计算了3 MPa下、工作频率60 Hz下,脉管制冷机的合理工作阻抗区域。而后通过实验测量了直线电机调相所实际提供的制冷机出口阻抗范围,并研究了整机在80 K下的制冷量与相对卡诺效率,同时分析了回收电功以及电机效率随电机负载的变化。最终,制冷机能够以最大29.5%的相对卡诺效率获得119 W制冷量。最大制冷量为154 W,此时直线电机能回收220 W电能。

The outlet impedance of the pulse tube cryocooler has a crucial influence on the performance of cryocooler. In this paper, a linear motor is used as a phase adjuster mechanism to adjust the outlet impedance of the cryocooler by adjusting the external load of the motor, at the same time, the linear motor is also used to recover the expansion work of the cryocooler and transform into electric energy for recovery. Based on the classical thermoacoustic theory, the reasonable operating impedance region of the cryocooler under 3 MPa and working frequency 60 Hz is calculated. After that, the output impedance range of the cryocooler provided by the linear motor phase adjuster is measured. The cooling capacity and the relative Carnot efficiency of the whole system under 80 K are studied. Meanwhile, the change of the recovery power and motor efficiency with the external load of the motor is analyzed. In the end, the cryocooler can obtain a 119 W refrigeration capacity at a maximum of 29.5% relative Carnot efficiency. The maximum cooling capacity is 154 W, and the linear motor can recover 220 W power at this time.