Study Of Theory And Testing On A Moving Magnet Linear Compressor

The research theme of this dissertation is the designing theory of A Moving Magnet Linear Compressor (MMLC) and its control scheme in order to develop high effective compressor to meet the need of refrigerator's high efficiency and saving energy. Based on a great deal of domestic and overseas information, the origin thoughts, new theories and technologies of correlative subjects, A MMLC is made for refrigerator. The dynamics, designing, optimization and control strategy as well as some key technologies of the MMLC are studied systematically by combing theoretical analysis , computer simulation with experiment.Based on analyzing the mechanical-electricity energy transition laws of the linear Motors, the mathematics model of Moving Magnet Linear Oscillating Motors (MMLOM) is built, with equivalent magnetic circuit and magnetic field resolution based on equivalent body electrical current density respectively. Then the inner essence is described among electricity , magnet and force of MMLOM. the flux linkage and the trust formulation of the MMLOM are deduced. Computed results by the proposed model are compared with those generated from finite element method, which shows in good agreements.Based on analyzing the working principal of the MMLC, its dynamic equation is established. The simple linearity approach and the describing function approach are employed to linearize the nonlinear gas force. compared with the nonlinear dynamic equation, system equivalent linear model established by the describing function approach can reflect its real characteristics, furthermore, a few main characteristics of the compressor are analyzing , which lay a foundation on building a set of designing and controlling method of MMLOC. Moreover, compressor system vibration characteristic's analysis shows that MMLOC must work in resonance circumscription in order to absorb electromagnetism energy much effectively.Based on the theory analysis of MMLC, a set of designing method is built, and a MMLC is made and testing under no gas force and gas force respectively. Furthermore, selectionmethod of spring's resonance frequency> winding electric current density^ permanent magnet average magnetic induction strength and its influence on MMLOC performance is analyzed and main structure parameter's calculating formula is deduced, experimentation indicate that MPMLOC have high efficiency and saving energy potential.Based on analyzing the regulating principal and method of the exhausting capacity of MMLC, a kind of testing method of piston displacement unemployed sense organ based winding flux linkage is proposed. A set of voltage control system is built to control and regulate the piston's displacement remaining displacement and average position to make the auto-regulating of exhausting capacity. Furthermore, control system is also simulated.In the end, the study contents and conclusion of the dissertation have been summarized, and the further research works have been forecast.