PIEZOELECTRIC TRANSFORMER

Recent applications of piezoelectric: materials to the active control of structural systems have been approached as a control problem in which actuator and sensor dynamics are important. Although successful control has been achieved, the synthesis of smart structures is difficult without a unified formulation, This work describes a different modeling and design method whereby the piezoelectric system is formulated by two sets of second-order equations, one for the mechanical system, and the other for the electrical system, coupled through the piezoelectric effect. The solution to this electromechanical coupled system gives a physical interpretation of the piezoelectric effect as a piezoelectric transformer. The piezoelectric transformer is a part of the piezoelectric system, which transfers the applied mechanical force into a force-controlled current source, and short circuit mechanical compliance into capacitance, It also transfers the voltage source into a voltage-controlled relative velocity input and free motional capacitance into mechanical compliance, The formulation and interpretation simplify the modeling of smart structures and lead to physical insight that aids the designer, Because of its physical realization, the smart structural system can be unconditional stable and effectively control responses, This new concept has been demonstrated in three numerical examples for a simple piezoelectric system.