Power flow tracing algorithm for electric networks with loopflow

This paper presents a novel power flow tracing (PFT) algorithm for electric networks with loopflow (ENL)—PFT(EN)L algorithm. During calculating process, the simplified network is obtained using the equivalent node for the loopflow part of a network. Graph theory is applied to determining the directed path from any generator-bus to load-buses with the proposed algorithm. Based on the AC load flow, the proportional sharing principle, series theory and the directed paths, the contribution of generators to the line flows and the extraction of loads from the generators can be calculated. The definitions and properties of auto-loopflow-coefficient (ALC) of an ENL are proposed. In this paper, two theorems have been proved: one is that the PFTL algorithm is always convergent with the properties of ALC; and the other is that the condition under which the whole contribution of any generator to all loads equals the output of the generator for a lossless ENL will be well satisfied with the PFTL algorithm. The developed algorithm has been tested on a number of test systems and the results show the feasibility and applicability of the approach.