Design of a Self-Adjusting Terminal Connector Based on Shape Memory Alloys

In electrical engineering terminal connectors are commonly used for connecting and releasing electrical conductors. Within the clamp or contact area the conductor is clamped safely and steadily by a mechanical mechanism to ensure a connection with a consistent quality and safety during the whole period of application. Terminal connectors are used to transfer power in the low and mid voltage range and for transmitting information. The contact force can decrease and the conductor can become loose. This happens due to an inappropriate installation of the conductor in the terminal connector, vibrations, temperature changes as well as the creepage of the contact material, mostly of the conductor. This may lead to damages or fires. Conventional connectors with a self-adjusting capability are not available for all conductor diameters respectively currents and are comparatively cost-intensive. In this paper a self-adjusting terminal connector based on shape memory alloy is developed to enhance a common screw terminal by the integration of a SMA cylinder and the terminal connector is then evaluated regarding its performance and capability.