Study Of Active Vibration Control System With Linear Electromagnet-Drived AMD

Active Mass Driver (AMD) control system is getting widely used in the field of civil engineering structure vibration control, where hydraulic actuators and rotatory servo motors are often used as driving devices. While lots of subsidiary equipments are needed for hydraulic actuators, and necessary mechanical transmission components are required in rotatory motor systems. With the advantage of directly driving, linear motors have been attracting more and more studying concern to be incorporated into AMD control systems. Based on the theory of linear electromagnet-drived AMD (LEMD-AMD) system, one set of LEMD-AMD model for experiments was designed in this dissertation. The AMD actuator was established from frequency transducer and asynchronous linear motor, under control of MultiQ-3 card. And thus, the linear electromagnet-drived AMD system was setup on a Benchmark scale model of a three-story building and some self-excited vibration control experiments were carried out. The results showed that good performance could be obtained.First, the dynamic model of the civil engineering structures and the theory of LEMD-AMD were reviewed. The dissertation summarized the requirement for actuators from the active vibration control system, and discussed the advantage for linear electromagnet driving technology to be taken into the field of vibration control. The problems to be settled for LEMD-AMD actuators, which are the key issues for LEMD-AMD system design, were proposed, too.Then, a linear actuator for the LEMD-AMD control system was designed. After discussing of the requirement from AMD system and the present situation of servo linear motor products, a scheme of building AMD actuators with asynchronous linear motors was proposed. To improve the linear motor's performance, control model of the asynchronous linear motor was established and then a lag-lead compensator and PID adjustor were taken in to improve the precision and the frequency response. Besides, discussion of asynchronous linear motors led to some suggestion to improve the performance further more.At last, structure vibration control Benchmark model, a three-story building was reproduced and its parameters for the dynamic structure vibration control model were analyzed with finite element method (FEM). The controller for the building active vibration control was designed according to LQG arithmetic. With the actuator, a whole series of experiment equipments were setup on the benchmark model and some self-excited vibration control experiments were carried out to test the actuator and the AMD controller. Results of the experiments provided experimental basis for further design.Based on designing of the linear electromagnet-drived AMD actuator and structure self-simulation vibration control experimental studies, the requirements of AMD in characteristic of precision and response frequency at low frequencies could be fully fitted by the actuator of frequency transducer and asynchronous linear motor, with the advantage of low cost and convenient controlling. And thus, the feasibility of using linear electromagnet driving within the field of AMD vibration control has been well validated by the experiments, which also lays out the foundation of further LEMD-AMD system research and its application in practical engineering.