Unexpected power changes may lead to transmission line overload and even evolve into cascading breakout. To avoid this, the key is to analyze how the power flow transfers after disturbance. When the scale of the system is large, the accurate calculation of power flow transferring will require a lot of calculation and become more difficult. From the perspective of complex network, we build a bridge between path length and power correlation rate. The former is an inherent property of the network, and the latter is an electrical quantity for a specific power disturbance. We find that power, similar to liquids, tends to flow along the fast-moving path, that is, the path with short path length. Finally, the results are verified in radial and ring network respectively. It is hoped that this will provide an intuitive understanding for power system operators.

Power flow, power transferring, complex network, the shortest path