The invention relates to the field of
power electronics, and aims to provide an LC buffer current-limiting circuit-based
hybrid DC circuit breaker. The
circuit breaker comprises two parts comprising an auxiliary
branch and a
main branch in parallel, wherein an auxiliary DC switch and a main DC switch are respectively arranged, the auxiliary DC switch comprises a rapid isolation switch and an IGBT valve group which are connected in series, the main DC switch comprises an IGBT valve group and a
metal oxide lightning arrester which are connected in parallel, an LC buffer current-limiting circuit is arranged in series in the
main branch, and in the structure of the LC buffer current-limiting circuit, a buffer
capacitor is connected in parallel with the
metal oxide lightning arrester, is connected in series with a
thyristor reversely connected in parallel and is finally connected in parallel with a current-limiting
inductor to form the LC buffer current-limiting circuit. The LC buffer current-limiting loop is employed, fault current rising can be effectively limited, the open-circuit circuit is reduced, the MOA
energy consumption is reduced, and the fault circuit removal speed is accelerated; and by employing a half-control device
thyristor, the numbers of full-control device IGBTs are reduced, so that the control difficulty and the
system cost are reduced, and the
circuit breaker is reasonable in design, low in cost and high in reliability.