Among the three main classifications of dc circuit breakers (DCCB), solid-state circuit breakers (SSCB) provide faster fault isolation. SSCBs can aid in achieving less weight and small form factor flight-weight electric components that are competent with high power requirements. This article proposes a modified O-Z-source DCCB (MOZSCB) topology containing a thyristor as the main fault interrupting switch and a coupled inductor helping the commutation of the thyristor. The proposed topology is engaged with fewer components owing to lessening the weight/volume of the aircraft system and can interrupt the fault within 400μs. Also, the proposed topology is designed to overcome the drawbacks of previously proposed conventional O-Z-source DCCB, such as negative current flow through the load during reclosing and unwanted power flow while it\'s commissioning. The proposed topology also mitigates the issues of high current stress on the thyristor while reclosing. To validate the performance of the proposed MOZSCB, a laboratory prototype has been built with a system rating of 270V/10A.
