The present invention discloses a bidirectional combined type
direct current breaker and a control method thereof. The bidirectional combined type
direct current breaker comprises a principal current circuit, a no-
voltage circuit, a null-current circuit and an
energy absorption circuit, wherein the principal current circuit, the no-
voltage circuit, the null-current circuit and the
energy absorption circuit are in parallel. The principal current circuit employs a mechanical switch; the no-
voltage circuit employs a bi-directional
semiconductor switch formed through anti-parallel thyristors; the null-current circuit is a bi-directional
pulse current circuit formed by a precharge
capacitor, an
inductor and a
thyristor bridge; and the
energy absorption circuit employs a
metal-
oxide varistor. The present invention further discloses a control method of the bidirectional combined type
direct current breaker. According to the invention, the no-voltage circuit employs thyristors so that the on-state
voltage drop is small and the current commutation speed is fast, and a mechanical switch has sufficient
dielectric recovery time and post arc
dielectric recovery is reliable; a null-current circuit is adopted to realize quick shutdown of the thyristors, and the
breaking capacity of a breaker is great; and two working
modes are convenient to be realized, and the working capability of the breaker is easy to be improved. The bidirectional combined type direct current breaker and the control method thereof are applicable to the fault protection of a bi-directional direct current power
system, with small loss of long-term flow passage, rapid breaking motion, high work reliability and the like.