With　the　rapid　development　of　DC　power　system　in　recent　years,　more　stringent　requirements　have　been　put　forward　for　the　rapid　reliability　of　DC　circuit　breakers.　At　present,　series　and　parallel　breakers　are　commonly　used　in　medium-voltage　DC　circuit　breakers　to　improve　the　breaking　capacity,　but　there　are　some　problems　such　as　poor　uniformity　of　breakers,　large　size　of　circuit　breakers　and　high　cost.　In　this　paper,　a　double-break　DC　circuit　breaker　structure　based　on　reactance　coupler　is　proposed.　In　the　process　of　current　breaking,　two　vacuum　switches　in　series　operate　simultaneously,　and　the　capacitive　discharge　and　reactance　coupler　are　used　to　realize　rapid　current　commutation,　which　improves　the　voltage　bearing　capacity　of　the　circuit　breaker.　Connecting　IGCT　in　the　commutator　branch　can　shorten　the　break　time　and　make　reclosing　easier.　The　working　principle　of　the　circuit　breaker　is　analyzed,　and　the　rationality　of　the　proposed　scheme　is　verified　by　simulation　calculation.　©　2021　IEEE.