【摘要】In electric power systems, the flow of electric power is an important issue for the control and management of the system. However, under transient-states caused by electrical disturbances, it is not a simple task to determine the flow of transient disturbance energy in an analytic way with high accuracy. The proposed algorithm for the determination of transient disturbance energy flow is based on cross time-frequency analysis that provides time-and frequency- localized phase difference information. Hence, based on the cross time-frequency distribution of the transient voltage and current, the classical parameters in power systems are modified for transient analysis. The transient power factor angle will determine the direction of transient disturbance energy (real and reactive) flows in power distribution system networks. For the verification of the proposed algorithm, a practical model of a power system is simulated by EMTP (Electromagnetic Transient Program). In addition, knowledge of this nature should greatly facilitate automatic identification of transient events and determination of the physical location of the source of various transient disturbances.