Title:  Control Strategies for Piezoelectrically Actuated Fast Mechanical Disconnect Switches for Hybrid Circuit Breakers

Committee:

Dr. Lukas Graber, ECE, Chair , Advisor

Dr. Maryam Saeedifard, ECE

Dr. Santiago Grijalva, ECE

Dr. Deepakraj Divan, ECE

Dr. Michael Steurer, Florida State

Abstract: The objective of the proposed research is to develop the switching motion control strategies for piezoelectrically-actuated fast mechanical switches to generate fast and steady contact movements to satisfy the requirements of hybrid circuit breakers. The proposed switching motion controllers are expected to balance the requirements for a heavy mechanical payload, a fast switching response, and a large displacement range meanwhile tackling the challenge of excessive vibration in travel curves. Broad selections of active damping filters with their systematic tuning principles are established in this research. Comprehensive evaluations are performed through controller-in-the-loop simulations and hardware implementation tests to demonstrate the vibration attenuation performance of proposed switching motion controllers. With more linear and vibration-damped travel curves, the overall piezoelectrically-actuated fast mechanical switch can achieve the faster switching speed and accommodate more complicated circuit interruption operations to better protect the medium-voltage direct-current power systems.