Study Of Electromagnetic System For Static Magnetic Refrigerator

Magnetic refrigeration, as a efficiency and clean way for refrigeration, has broad application prospects. In order to solve the problem of the presence of moving parts in traditional magnetic refrigerator, this paper presents a novel static magnetic refrigerator.First of all, this paper discusses working principle of the new static refrigerator, and mainly design on electromagnetic system in magnetic refrigerator, including permanent magnetic circuit and corresponding magnetization and demagnetization system. The design index of each part in electromagnetic system is determined based on analysis.Second is the experimental research on magnetization and demagnetization characteristics of permanent magnet material. Experiments show that for permanent magnetic materials, such as Nd-Fe-B, magnetization can be completed when magnetic induction intensity is more than 2.7T, and oscillating magnetic field is used for demagnetization, after which, residual magnetism of permanent magnet is reduced considerably..Then is the design of permanent magnetic circuit in magnetic refrigerator and FEM model is used to optimize structural parameters of permanent magnetic circuit. When permanent magnet is saturate, air gap field of the final designed permanent magnetic circuit can fully meet the demand of magnetic refrigeration. After that, FEM model is used again to design magnetization and demagnetization system of permanent magnetic circuit, including coils and power supply.At last, permanent magnetic circuit and magnetization and demagnetization system are assembled, and magnetization and demagnetization are tested for permanent magnetic circuit. Experimental results show that permanent magnet in permanent magnetic circuit can be magnetized by the system to saturation, under which, air gap field of magnetic circuit can meet the demand of magnetic refrigeration, and is reduced considerably after demagnetization, about 30% of saturation. Thus, utilization of electromagnetic system in magnetic refrigerator is feasible.