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This paper describes the structural design of an active flow-control experiment. The aim of the experiment is to investigate the increase in efficiency of an internally blown Coanda flap using unsteady blowing. The system uses tailor-made microelectromechanical (MEMS) pressure sensors to determine the state of the oncoming flow and an actuated lip to regulate the mass flow and velocity of a stream near a wall over the internally blown flap. Sensors and actuators are integrated into a highly loaded system that is extremely compact. The sensors are connected to a bus system that feeds the data into a real-time control system. The piezoelectric actuators using the d 33 effect at a comparable low voltage of 120 V are integrated into a lip that controls the blowout slot height. The system is designed for closed-loop control that efficiently avoids flow separation on the Coanda flap. The setup is designed for water-tunnel experiments in order to reduce the free-stream velocity and the system's control frequency by a factor of 10 compared with that in air. This paper outlines the function and verification of the system's main components and their development.

Elec tric P o we r C ompo ne nts and Syste ms, 30:981-999, 2002 C opyright c This article is aimed at designing a robust-controller for vector-controlled induction motor drive systems based on the Q-parameterization theory. The set of all stabilizing controllers for the system is characterized by two free Q-parameters of the controllers. The Q-parameters are chosen using an optimization technique to satisfy the design requirements. To demonstrate the eOEectiveness of the proposed controller, the calculated motor speed and torqueproducing current component in presence of core-loss are compared with those measured in the literature. Simulation results show that good response of the control system due to the step change-of-speed command/load torque can be achieved using the proposed controller.

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