Active vibration control of a smart plate using a piezoelectric sensor-actuator pair at elevated temperatures

A new scheme for active structural vibration control using piezoelectric patches at elevated temperatures is analytically derived and experimentally verified. A control law is derived using augmented piezoelectric constitutive equations which include the temperature dependence of piezoelectric stress coefficient (e(31)) and permittivity (is an element of(33)). Since the temperature dependence of 'e(31)' and 'is an element of(33)' is not analytically known, their experimental values measured at elevated temperatures are used. Using augmented constitutive equations, a finite element model of a smart two-dimensional isotropic plate instrumented with a collocated piezoelectric sensor-actuator pair is derived. A control law for active vibration control of the first mode of the smart cantilevered plate is derived using negative velocity feedback. Active vibration control of the first mode of a smart cantilevered plate is experimentally achieved at elevated temperatures ranging from 25 to 75 degrees C under two cases: (i) using a control law which ignores the temperature dependence of 'e(31)' and 'is an element of(33)' and (ii) using a control law which includes the temperature dependence of 'e(31)' and 'is an element of(33)'. A comparison between these two control laws shows that: (i) active vibration control (AVC) performance is not maintained at elevated temperatures using a control law which ignores the temperature dependence of 'e(31)' and 'is an element of(33)' and (ii) AVC performance is maintained at elevated temperatures when we use a control law which includes the temperature dependence of 'e(31)' and 'is an element of(33)'.