Study On Piezoelectric Self-Sensing Actuator Decoupling Based On Signal Processing

Recent several years, smart structure vibration control has attracted many attentions. As a kind of new smart material, piezoelectric materials are widely used in the area of structure vibration control, because of its well machine-electric coupling characteristic and wide dynamic frequency range. Self-sensing actuators (SSA) made of piezoelectric materials with the advantages of simple structure, high response speed, strong adaptability at high frequency, have great application expedition in vibration control, structure health monitoring, system identification and MEMS.Study on piezoelectric actuators is focusing on the research of the decoupling of the sensing and the actuation signal at present. Bridge circuit method is a widely method. In this paper, Blind Source Separation (BSS) and adaptive signal processing based decoupling method are proposed. Theoretical analysis and experimental results show the feasibility of them.This paper is composed of six parts. First, the principle of signal decoupling for piezoelectric self-sensing actuator by using BSS and adaptive technique is introduced based on the theory of the bidirectional power conversion and the signal characteristics in practical operation. Second, A piezoelectric beam is constructed, Detect circuit of blind source separation observation signals is designed, The hardware system based on BSS technique are composed of the other signal processing circuit, NI_PCI6221 data acquisition, piezoelectric beam and detect circuit; Detect circuit of adaptive signal processing technique is designed , The hardware system is constructed by the other signal processing circuit, detect circuit and TMS320F2812 system. Third, The software system based on BSS technique is founded by LabVIEW and MATLAB mixed programming, The software system based on adaptive signal processing is built by software design in ccs2.1 of TMS320F2812 system. Fourth, the feasibility of the method of BSS and adaptive signal processing in decoupling the mixed signals are verified by the experiments based on the said software and hardware systems. Using the obtained decoupling signal, algorithm for closed-loop control is designed as well. Fifth, the system identification is done on the piezoelectric cantilever beam to deign the PID controller, and computer simulation of the incomplete derivative PID algorithm is completed as well. Sixth, the improved LMS based adaptive filtering algorithm and the Z transmitting incomplete derivative PID algorithm are realized by programming and debugging...