Electrically controlled switching device including shape memory alloy element

A method of operating an electrically controlled switching device, the method comprising:

• connecting a heat sink directly to a support;
• coupling a contact carrier directly with a second contact;
• delivering an electrical pulse to a shape memory alloy (SMA) element, which transforms between a first shape and a different second shape when heated to a transformation temperature, to heat the SMA element to a desired temperature less than the transformation temperature;
• connecting a first end of the SMA element directly and fixedly to the heat sink and a second end of the SMA element directly and fixedly to the contact carrier;
• detecting a detected temperature of the SMA element using a sensor positioned on or adjacent to the SMA element;
• and
• adjusting the electrical pulse being delivered to the SMA element to maintain the detected temperature of the SMA element at about the desired temperature.

An electrically controlled switching device comprising:

• a support;
• a first contact coupled to the support;
• a second contact coupled to the support and movable toward and away from the first contact;
• a shape memory alloy (SMA) element operably connected with the second contact and configured to transform between a first shape and a different second shape responsive to an electrical pulse heating the SMA element to a transformation temperature;
• a sensor positioned on or adjacent to the SMA element and configured to detect a detected temperature of the SMA element;
• a heat sink directly connected to the support;
• a contact carrier directly coupled with the second contact, wherein the SMA element includes a first end directly and fixedly connected to the heat sink and a second end directly and fixedly connected to the contact carrier;
• and
• a controller configured to control the electrical pulse at least between a pre-heating state and a transformation state, wherein in the pre-heating state the controller controls the electrical pulse being delivered to the SMA element so as to heat the SMA element to a first desired temperature, which is less than the transformation temperature, wherein in the transformation state the controller controls the electrical pulse being delivered to the SMA element so as to heat the SMA element to a second desired temperature, which is equal to or greater than the transformation temperature, and wherein the controller receives signals from the sensor indicative of the temperature of the SMA element.