Active Vibration Control Of Piezo Stack Actuator With Consideration To Hysteresis And Saturation Effects

• Main Author: Mazlan , Ahmad Ahmad Zhafran
• Format: Thesis
• Language: English
• Published: 2016
• Subjects: T Technology; TJ1-1570 Mechanical engineering and machinery
• Online Access: http://eprints.usm.my/41004/1/Active_Vibration_Control_Of_Piezo_Stack_Actuator_With_Consideration_To_Hysteresis_And_Saturation_Effects.pdf; http://eprints.usm.my/41004/
• Institution: Universiti Sains Malaysia

Tindak balas penggerak piezo bertindih dari segi daya-sesaran-pecutan sebagai fungsi pengujaan voltan dan frekuensi diukur bagi menentukan ciri-ciri histeresis dan ketepuan yang boleh diwakili oleh persamaan kuadratik polinomial. Ketepuan daya, sesaran dan pecutan berlaku daripada 400 Hz sehingga 500 Hz untuk 400 V voltan pengujaan. Ciri-ciri histeresis dan ketepuan ini kemudiannya digunakan di dalam sistem kawalan getaran aktif dan mengakibatkan pengurangan ralat sebanyak 50 - 67 %. Ini membuktikan kepentingan memasukkan histeresis dan ketepuan penggerak di dalam reka bentuk sistem kawalan getaran aktif. Pengukuran kebolehpindahan menunjukkan julat frekuensi berkesan pada 250 - 450 Hz. Kebolehgunaan secara praktikal sistem kawalan getaran aktif telah disiasat dengan menggunakannya pada mesin pencanai elektrik yang berkelajuan nominal 25000 rpm dan kebolehpindahan getaran berkurangan sebanyak 91 %. Penambahbaikan telah dicapai menggunakan model histeresis lelurus bersama-sama tiga skim anti-gegulung (pengapitan, pengiraan-belakang dan mod jejakan) untuk mengelakkan ketepuan voltan pantas pada penggerak piezo bertindih dan prestasinya telah dibandingkan dengan skim kawalan daya aktif. Hasil kajian menunjukkan sistem PID-kawalan daya aktif adalah lebih baik daripada PID-anti-gegulung dengan jumlah pengurangan kebolehpindahan getaran sebanyak 97.7 %. Getaran struktur boleh dihadkan supaya kurang daripada nilai tepu sesaran penggerak di dalam sistem kawalan getaran aktif dengan melakukan pengubahsuaian struktur dinamik dan ini telah menyebabkan perlebaran julat frekuensi berkesan kepada 200 - 510 Hz dengan pengurangan kebolehpindahan getaran sebanyak 96 % berbanding dengan reka bentuk asal. Di dalam penyelidikan ini, sumbangan utama adalah penentuan lengkungan histeresis dan ketepuan bagi penggerak piezo bertindih dari segi daya-sesaran-voltan sebagai fungsi pengujaan frekuensi. ________________________________________________________________________________________________________________________ The piezo stack actuator response in terms of force-displacement-acceleration as a function of the excitation voltage and frequency are measured to determine the hysteresis and saturation characteristics which are represented using quadratic polynomial equations. Saturation of force, displacement and acceleration occurred from 400 Hz to 500 Hz for the 400 V excitation voltages. These hysteresis and saturation characteristics are used in the active vibration control (AVC) system which resulted in error reduction of 50 - 67 %. This proves the importance of including the hysteresis and saturation of the actuator in the design of the AVC system. Transmissibility measurement showed the effective frequency range of 250 - 450 Hz. The practical applicability of the AVC system was investigated using an electric die grinder with a nominal speed of 25000 rpm and the vibration transmissibility was reduced by 91 %. Further improvement was achieved using the linearized hysteresis model together with three anti-windup schemes (clamping, back-calculation and tracking mode) to avoid fast voltage saturation of the piezo stack actuator and the performance was compared with the active force control (AFC) scheme. The results showed that the PID-AFC was superior to the PID-anti-windup schemes with a total vibration transmissibility reduction of 97.7 %. The vibration of the structure can be limited to be less than the saturation displacement of the actuator in the AVC system using the structural dynamic modification (SDM) and this has resulted in a wider effective frequency range of 200 - 510 Hz with the vibration transmissibility reduction of 96 % when compared with the initial design. In this research, the main contribution is the determination of the hysteresis and saturation curves of the piezo stack actuator in terms of force-displacement-voltage relationship as a function of excitation frequencies.