Harmonic Power Flow using multi-segment frequency-dependent transmission line models

This paper introduces a Harmonic Power Flow (HPF) tool that uses frequency-dependent line models characterized by a frequency-dependent line model structure. The line model structure used is depicted by multiple lumped parameter segments, in which the line model segmentation (the number of segments) depends on the harmonic frequency being computed. The proposed HPF method employs a non-iterative power flow technique. The tool has been coded in Matlab and a test study was performed for a three-bus power system with a non-linear load injecting harmonic currents. Results of the test studies using the proposed HPF tool are compared to results obtained using a single lumped parameter segment line model (i.e. the traditional PI model) as well as using the frequency-dependent line model used in the PSCAD software. In general, the results obtained using the proposed HPF tool with frequency-dependent line model structures are closer to the results obtained using the frequency-dependent line models in PSCAD than the ones using a single-segment line model.