TY - JOUR

T1 - Parametric study on the optimal tuning of an inertial actuator for vibration control of a plate

T2 - Theory and experiments

AU - Camperi, Stefano

AU - Ghandchi Tehrani, Maryam

AU - Elliott, Stephen John

N1 - Funding Information:
The authors gratefully acknowledge the European Commission for its support of the Marie Skłodowska-Curie program through the ITN ANTARES Project (GA 606817 ).
Funding Information:
The authors gratefully acknowledge the European Commission for its support of the Marie Skłodowska-Curie program through the ITN ANTARES Project (GA 606817).
Publisher Copyright:
© 2018 Elsevier Ltd
Copyright:
Copyright 2018 Elsevier B.V., All rights reserved.

PY - 2018/11/24

Y1 - 2018/11/24

N2 - This paper presents a theoretical and experimental tuning of the velocity feedback gain of a plate with an inertial actuator. The objective of the study is to analyse a direct velocity feedback control unit, which can be tuned locally and yet providing a global vibration reduction. This is achieved through the knowledge of the velocity signal and the actuator dynamics, without information on the plate dynamics. In practice, an electrical input is provided to the actuator, proportional to the local velocity of the structure, in such a way to generate active damping. The tuning is performed by maximising the power absorbed by the inertial actuator from the structure, and this is shown to be equivalent to the minimisation of the global level of vibration, estimated through the kinetic energy of the structure. Nine accelerometers have been used, and the performance for several values of different feedback gains has been investigated. Moreover, the influence of the frequency range of integration in the tuning of the velocity feedback gain is considered, and it is found experimentally that a broadband reduction up to 5 dB can be achieved, as expected from the numerical model. The absorbed power from the plate by the control unit is found to be negative below the first natural frequency of the inertial actuator, when the feedback control is implemented. This is due to the fact that, although a collocated velocity feedback is implemented, the control system is only conditionally stable because of the actuator dynamics. The performance of active control is found to reduce dramatically, if instability occurs for gains lower than the optimal one. For this reason, the work is enriched with a parametric study on the plate-actuator pair, in which the influence of the dynamic properties of the plate and the inertial actuator are investigated. The effectiveness of the active control is found to depend on the mass ratio between the actuator and the plate. In particular, for low mass ratios, the system well approximate the ideal case, in which a control force is proportional to the velocity of the plate, but for high mass ratios, a small amount of active damping can be introduced.

AB - This paper presents a theoretical and experimental tuning of the velocity feedback gain of a plate with an inertial actuator. The objective of the study is to analyse a direct velocity feedback control unit, which can be tuned locally and yet providing a global vibration reduction. This is achieved through the knowledge of the velocity signal and the actuator dynamics, without information on the plate dynamics. In practice, an electrical input is provided to the actuator, proportional to the local velocity of the structure, in such a way to generate active damping. The tuning is performed by maximising the power absorbed by the inertial actuator from the structure, and this is shown to be equivalent to the minimisation of the global level of vibration, estimated through the kinetic energy of the structure. Nine accelerometers have been used, and the performance for several values of different feedback gains has been investigated. Moreover, the influence of the frequency range of integration in the tuning of the velocity feedback gain is considered, and it is found experimentally that a broadband reduction up to 5 dB can be achieved, as expected from the numerical model. The absorbed power from the plate by the control unit is found to be negative below the first natural frequency of the inertial actuator, when the feedback control is implemented. This is due to the fact that, although a collocated velocity feedback is implemented, the control system is only conditionally stable because of the actuator dynamics. The performance of active control is found to reduce dramatically, if instability occurs for gains lower than the optimal one. For this reason, the work is enriched with a parametric study on the plate-actuator pair, in which the influence of the dynamic properties of the plate and the inertial actuator are investigated. The effectiveness of the active control is found to depend on the mass ratio between the actuator and the plate. In particular, for low mass ratios, the system well approximate the ideal case, in which a control force is proportional to the velocity of the plate, but for high mass ratios, a small amount of active damping can be introduced.

KW - Active velocity feedback

KW - Inertial actuator

KW - Optimal tuning

KW - Power absorption

KW - Structural vibration

UR - http://www.scopus.com/inward/record.url?scp=85051663246&partnerID=8YFLogxK

U2 - 10.1016/j.jsv.2018.07.048

DO - 10.1016/j.jsv.2018.07.048

M3 - Article

AN - SCOPUS:85051663246

SN - 0022-460X

VL - 435

SP - 1

EP - 22

JO - Journal of sound and vibration

JF - Journal of sound and vibration

ER -