A novel hysteresis reducing piezoceramic amplifier

Piezoceramic materials exhibit hysteresis that forces the use of advanced algorithms in control applications, and thus limiting the potential to move from laboratory to large scale field applications. Using the nonlinear electromechanical model of piezoelectric materials as the basis for understanding the behaviors of the actuator, piezoceramic materials should be controlled using charge to effectively reduce hysteresis. On the other hand, commercial amplifiers use voltage feedback control to actuate piezoceramic materials. In this paper, the previously designed piezoceramic amplifier was fitted with a Linear Quadratic Gaussian (LQG) tracking controller to allow the reduction of hysteresis through current feedback. Tests were conducted on a two story concrete frame by comparing the frequency response of an embedded smart aggregate sensor with the reference current applied to another embedded smart aggregate actuator. From the latter test, results show a reduction of the hysteresis of about 60% in the 10 to 3k [Hz] range. In addition, the overall harmonic distortion dropped by 16%.