Energy-efficient Actuation Concepts for SMAs

Inhalt:
Despite their numerous attractive advantages, such as their exceptional energy density, only a few SMA-based actuator systems are commercially available today. One of the remaining obstacles is their high energy consumption during thermal activation. This presentation introduces innovative design and control approaches to increase efficiency of SMA-based actuator systems. Bi-stable spring elements in combination with an antagonistic SMA wire configuration can be used in on/off applications to eliminates the disadvantages of slow actuation and energy inefficiency. The activation of SMA wires with high power pulses is another approach for the realization of high-speed actuation and energy efficiency. This control concept can also be applied for high AC voltages such as typical mains supplies and leads to actuation times in the millisecond range and energy savings of up to 80% in comparison to common SMA wire activation.