Novel concept for medium voltage circuit breakers using microswitches

This letter presents a new concept for circuit breakers (CBs) using microelectromechanical switches (MEMS). The building block is a switching unit, including a micro-switch shunted by a diode. Several switching units are connected in series and in parallel to form a switching string assembly. The opening of the mechanical switches transfers the current to the diodes. The diodes interrupt the current at the first zero crossing. The use of micro-switches miniaturizes the CB and assures arc less current interruption by the end of the first half cycle.