Abstract:
In distribution networks, the parameters of overhead lines vary with different frequency bands, which significantly reduces the accuracy of traditional fault location methods that assume constant line parameters. To address this issue, firstly, the mechanism of frequency-dependent variation of distribution line parameters is analyzed, with full consideration of the influence of the skin effect on line parameters. Then, the line transfer function difference matrix is used as a variable to convert the fault location problem into an optimization solution problem. Finally, a distribution network fault location method based on the traveling wave transfer function difference matrix is proposed. A typical unbalanced distribution network scenario is built in PSCAD to simulate various fault conditions. The simulation results show that the proposed method can effectively overcome the influence of frequency-dependent line parameters on existing traveling waves, with an error within 60 m under most operating conditions, which provides a new idea for distribution network fault location.