A Study of Active Rotor-Blade Vibration Control using Electro-Magnetic Actuation - Part II: Experiment

This is the second paper in a two-part study on active rotor-blade vibration control. This part presents an experimental contribution into the work of active controller design for rotor-blade systems. The primary aim is to give an experimental validation and show the applicability of the theoretical results presented in part 1 of the study.

A test rig of a coupled rotor-blade system, where blades flexible motion is coupled to rotor lateral motion, is build for the experimental research. The rig is build by four flexible blades radially attached onto a rotating rigid disc and shaft. The rigid shaft is mounted in a flexible hub, which can perform lateral movement.

The blades are designed as simple Euler-Bernoulli beams with tip masses in order to increase the vibration coupling among the rigid rotors and the flexible blades motion. Different schemes of blade configurations, with and without mistuning, can easily be generated by substitution or rearranging the blades.

Six sets of electro-magnetic actuators are applied to the system in order to control the blades as well as the rotor vibrations. Four sets of actuators are mounted in the rotating disc acting directly onto each one of the blades. The remaining two sets of actuators are applied to act directly onto the hub, working as an active radial bearing controlling the rotor lateral movement.

The rig is equipped with sensors measuring blade and rotor vibrations. Actuators and sensors are connected to a digital signal processor running the control algorithm. Measurement signals and actuator control signals from the sensors and actuators fixed in the rotating disc are transmitted to the control unit through a slip-ring device.

Various measured responses of both the controlled and the non-controlled system with identical blades and with deliberately mistuned blades are shown in the paper. The results reveal the potential of the control technique presented in the part 1 paper.