Centralized and decentralized control of structural vibration and sound radiation

This paper examines the performance of centralized and decentralized feedback controllers on a plate with multiple colocated velocity sensors and force actuators. The performance is measured by the reduction in either kinetic energy or sound radiation, when the plate is excited with a randomly distributed, white pressure field or colored noise. The trade-off between performance and control effort is examined for each case. The controllers examined are decentralized absolute velocity feedback, centralized absolute velocity feedback control and linear quadratic Gaussian (LQG) control. It is seen that, despite the fact that LQG control is a centralized, dynamic controller, there is little overall performance improvement in comparison to decentralized direct velocity feedback control if both are limited to the same control effort.