Design And Application Of Natural Frenquency Adjustable Electromagnetic Actuator

An inertia electromagnetic actuator capable of adjusting natural frequency is designed inthis thesis. Simulation and experiments are carried out to study different algorithms.There are two procedures in the design of electromagnetic actuator: magnetic circuitdesign and stiffness conditioning design. ANSOFT software is used to simulate the magneticcircuit during the magnetic circuit design and optimize the design of the actuator. In order toadjust the natural frequency, the actuator spring is designed adjustable to meet the differentneed of the system stiffness. And performance test on prototype is done to lay goodfoundation for the following test on active vibration control.Through the research on the effect of different identification algorithms on the secondarypath of the filtered x-LMS method, the effect of these algorithms on active control ofvibration is discussed. Identification algorithms used in this paper include: research ondifferent identification method and the number of secondary path. The algorithms simulationshows validity of different algorithms.A test bench based on the theoretical studies is built. Control effects are in comparisonwith single secondary path identification using BP neural network and LMS algorithm. Thecontrol effects are also compared between single-multi-econdary and multi-secondary.Experiment results show that the response time of LMS response identification is shorterthan BP neural network identification. The vibration control-scale which used singlesecondary path is smaller. After comparing non-coupling multi-secondary path with couplingmulti-secondary path, algorithms using coupling secondary path have an overall control effect.Based on active vibration control using single secondary path, experiments on the influence ofdifferent natural frequency on the different structure of the actuator are carried out. Thevibration control effect is tested based on changing the natural frequency of the actuator. Theexperiment shows the good performance of the actuator, and the method to increase outputforce by changing natural frequency is reasonable.