Method and device for relieving power flow out-of-limit of novel power system

The invention discloses a method and a device for relieving power flow out-of-limit of a novel power system. The method comprises the following steps: determining a sensitivity index of a node injection active power variation relative to an active power flow variation of an overload power transmission line; defining an active power flow influence sensitivity factor relative to the overload power transmission line after the power transmission line is disconnected based on the sensitivity index; based on a direct current power flow method and an active power flow influence sensitivity factor, deriving a power flow variation calculation formula on an overload power transmission line caused after the power transmission line is broken, and giving a group of pre-breaking power transmission line schemes; and analyzing the pre-breaking power transmission line scheme based on a Newton-Raphson method, and evaluating a group of target power transmission line breaking schemes for relieving the tidal current overload prob