Patent attributes
The invention discloses an adaptive fault clearing scheme for an MMC VSC-HVDC grid based on source-grid coordination. A grid-side circuit breaker topology is disposed at each end of each DC line of the MMC VSC-HVDC grid to coordinate with a source-side control strategy when a fault occurs to the DC line so as to isolate the fault together. When a system runs stably, the voltage regulation controller does not actuate, after the fault occurs, the voltage regulation controller is started, and the output voltage regulation coefficient decreases, so that voltage at outlets of the converters drops accordingly, and coordinates with voltage of the pre-charging capacitor of the grid-side circuit breaker topology to realize fault isolation based on source-grid coordination. The adaptive fault clearing scheme provided by the invention greatly improves the speed of fault isolation.