Prototype Design And Preliminary Experiments Of A Dual-magnet Moving Magnet Linear Compressor For Cryocoolers

With the advantages of high reliability, low vibration and long life, cryocoolers are widely used in aerospace, military, electronic and medical fields. Linear compressor is the key to ensure such advantages of cryocoolers. In this paper, a dual-magnet moving magnet linear compressor is designed and manufactured, theoretical analysis and finite element analysis on key components are developed, preliminary test is carried out. The main content of the study includes:1. Dynamics and circuit model analysis of the linear compressor and design process of flexure bearingcomplex vector analysis method is used to analyze the forces applied to the moving parts of the compressor, the expressions of the moving mass, output PV power, input electric power, damping dissipation and the efficiency of the compressor are obtaind. Through circuit model analysis, the expression of efficiency in terms of impedance and the maximum output PV power within the given current limitation are shown and it’s indicated that the inductor and equivalent capacitance of the electrical circuit have no influence on the efficiency. Detailed design process of the flexure bearing is summed, providing reference for the flexure bearing design.2. Numerical simulation of key components of dual-magnet moving magnet linear compressorHysteresis loss generated within the yokes of a dual-magnet moving magnet linear motor is almost offset, which improves the efficiency of the motor. Preliminary analysis and design of the linear motor are developed based on numerical simulation, optimization design of the flexure bearing is conducted. Aiming to get an optimized structure of the linear motor, a number of different structures were constructed and calculated by FEM process. Flexure bearing is optimized through static structural and modal analysis, the maximum stress on the flexure bearing with different strokes, axial and radial stiffness, as well as the first natural frequency of the flexure bearing are investigated. Finally, the resonant frequency of the compressor is predicted according to the numerical simulation results.3. Preliminary experimental study of RC load for the linear compressorRC load approach can provide references for the matching between the linear compressor and the load. Experimental measurements based on the linear compressor with RC load are conducted to show the output characteristics under different operating conditions for the dual-magnet moving magnet linear compressor. The results is helpful for the matching between the linear compressor and the load as well as to improve the performance of the linear compressor.