221. EXTENDING VIBRATION AND WAVE PROPAGATION CONTROL USING PIEZOELECTRIC MATERIALS AND RESONANT SHUNTS TO COMPOSITE WIND TURBINE BLADES

Department: Structural Engineering
Faculty Advisor(s): Francesco Lanza di Scalea

Primary Student
Name: Jeffery Dwayne Tippmann
Email: jtippman@ucsd.edu
Phone: 858-534-6373
Grad Year: 2013

Abstract
In the year 2011 nearly 8 GW of renewable energy generating capacity using wind powered turbines was added to the electrical grid in the United States. This additional capacity is expected to have the equivalent annual energy output of one new nuclear power plant. Given one of the largest resources in the world, the United States should continue to see a strong growth of wind powered turbines in the next decade. Technologies being developed today will help sustain the growth of this clean source of energy generation well into the future. One possible technology is the use of piezoelectric materials and resonant shunts to mitigate structural vibrations and wave propagation in composite wind turbine blades. In a passive technique, the piezoelectric material converts mechanical strain into electrical energy, which is then damped through a shunt circuit. The resonance of the shunt circuit is used to target single or multiple modes of the structure. In addition to passive techniques, the piezoelectric materials can create mechanical energy when applied an electric current, allowing for the use of feedback control systems to create an active control system. The passive control using shunt circuits has been successfully demonstrated experimentally in a cantilevered beam subjected to first bending mode vibration. The results show an increase in damping as the shunt circuit is tuned to the appropriate resonant frequency. This experiment is currently being extended to wave propagation control on a small section of a 9-m composite research wind turbine blade. A finite element model of the research blade has been developed to aid in future coupled simulations of the structural response of the blade and the electrical response of the added piezoelectric materials.

« Back to Posters or Search Results