Patent ID: 11909201
Assignee: MITSUBISHI ELECTRIC CORPORATION
Field: Electrical machinery, apparatus, energy (Electrical engineering)
Classification: CPC H  Y | IPC H

Claim 0:
1. A multi-terminal DC power transmission system comprising:
a multi-terminal DC power grid including a plurality of protection zones, each protection zone being divided from an adjacent protection zone by a DC circuit breaker;
a plurality of individual protective devices provided corresponding to the protection zones; and
a common control device connected to the individual protective devices via a first communication network, wherein
each of the individual protective devices is configured, when detecting change in voltage or current in a corresponding protection zone due to fault occurrence in any of the protection zones, to output a fault signal pertaining to the fault occurrence to the common control device via the first communication network and open a DC circuit breaker that divides the corresponding protection zone such that the corresponding protection zone is disconnected from the multi-terminal DC power grid and deenergized, and
the common control device is configured to estimate a fault occurrence zone where a fault occurs among the protection zones, based on a plurality of received fault signals, each being the output fault signal, and request an individual protective device of the plurality of individual protection devices, corresponding to a deenergized protection zone of the plurality of protection zones excluding the fault occurrence zone to reclose the DC circuit breaker that divides the deenergized protection zone such that the deenergized protection zone is restored.