Key Line Identification of Power Network Considering Active and Reactive Power Coupling Relationship between Branches

In order to accurately identify critical branches which are of great significance to the safe and stable operation of power grid, a critical branch recognition method based on active and reactive power coupling relationship between branches is proposed. Respectively calculate active and reactive power coupling line factors of all branches and choose the bigger impact factor branch as the critical branch. The design of the key line identification index not only considers the influence of load level and transport margin the branch itself, but also takes into account the coupling relationship between active power and reactive power, so it can implement the accurate recognition of critical branch. Finally apply the method in a practical provincial network and identify critical branches under a particular operation mode. The result of PSD-BPA transient stability calculation verifies the effectiveness and adaptability of large power grid of the method.