In　this　paper.,　the　topology　of　DC　circuit　breaker　is　proposed.,　when　the　fault　current　occurs.,　the　sampling　circuit　detects　that　the　current　exceeds　the　threshold.,　and　immediately　starts　the　driving　power　supply　to　quickly　shut　down　the　JFET.,　but　the　JFET　is　susceptible　to　the　influence　of　line　parasitic　inductance　in　the　process　of　fault　current　removal.,　and　then　there　is　a　serious　overvoltage　problem.,　the　overvoltage　suppression　circuit　is　proposed.,　its　working　principle　is　analyzed　in　detail　and　the　circuit　parameters　are　designed.,　and　finally.,　the　circuit　breaker　prototype　is　developed　and　experimentally　verified.　The　results　show　that　the　circuit　breaker　has　good　rapidity　and　overvoltage　suppression　effect.　©　2024　IEEE.