Overcoming Actuators Saturation Problem in Structural Active Control

Since the actuator capacity is limited, in the real application of active control systems under severe earthquakes, it is conceivable that the actuators saturate, hence the actuator saturation should be considered as a constraint in the design of optimal controllers. In this paper, a new procedure for structural active control is proposed to overcome the actuators saturation. This approach is based on elimination of structural response as early as possible to save the high control force required later due to the response generated from the small recent response taking into consideration the actuator capacity. The proposed approach is formulated and applied to single and multi-story buildings subjected to ground motion. Two types of ground excitations are considered. The first is sinusoidal and in resonance with building. The second type of excitation represented by several real earthquakes. The proposed approach is compared with the traditional optimal control in two manners, when the maximum control force in the two approaches is maintained the same and when the response reduction level is the same. It is found that the proposed approach does not only overcome the actuator saturation, but it also reduces the response for all cases considered, namely, single or multi-story building, light or heavy damped structures, and when buildings are subjected to sinusoidal or real ground motion. {[}A. E. Bakeri. Overcoming Actuators Saturation Problem in Structural Active Control. Life Sci J 2012; 9(3): 533-539] (ISSN: 1097-8135). http://www.lifesciencesite.com.74