磁力涡旋压缩机永磁随变机构的力学特性

为减少涡旋压缩机运行时的机械接触，针对无油涡旋压缩机的结构特点提出一种永磁随变机构，并分析其力学特性. 首先，分析永磁随变机构的工作原理，采用虚位移法建立磁力模型，运用理论公式、有限元仿真和实验分析永磁随变机构工作气隙处的磁感应强度；其次，通过理论公式和有限元仿真，分析永磁随变机构结构参数与力学特性的关系；最后，通过磁力涡旋压缩机的性能参数和磁力测试实验对永磁随变机构的力学性能进行验证. 结果表明:永磁随变机构的径向磁力在一定范围内随着径向位移的增加而增加，随着轴向位移的增大而减小；在永磁随变机构工作中，径向位移与永磁随变机构刚度系数近似呈线性关系；在工作距离内永磁随变机构单组磁环的最小轴向磁力为8.73 N，在工作轨迹上的径向力为4.8 N，满足磁力涡旋压缩机的工作需求. 

Mechanical Properties of Scroll Compressor with Permanent Magnetic Compliance Mechanism

To reduce the mechanical contact of scroll compressor during operation, a novel permanent magnetic compliance mechanism is proposed according to the structural characteristics of oil-free scroll compressor, and its mechanical properties are analyzed. Firstly, the working principle of the permanent magnetic compliance mechanism is analyzed, the magnetic force model is established by the virtual displacement method, and the magnetic induction intensity at the working air gap of permanent magnetic compliance mechanism is analyzed by using theoretical formula, finite element simulation and experimental measurements. Secondly, the relationship between structural parameters and mechanical characteristics of permanent magnetic compliance mechanism is analyzed by theoretical formula calculation and finite element simulation. Finally, the mechanical properties of the permanent magnetic compliance mechanism are verified by the performance parameters of the magnetic scroll compressor and the magnetic force test. The results show that within a certain range, the radial magnetic force of the permanent magnetic compliance mechanism is proportional to the radial displacement and inversely proportional to the axial displacement. Radial displacement has approximately linear relationship with stiffness coefficient when permanent magnetic compliance mechanism works. Within the working distance, the minimum axial magnetic force of the single group magnetic ring with permanent magnetic compliance mechanism is 8.73 N, and the radial force on working trajectory is 4.8 N, which meets the working requirements of the magnetic scroll compressor.