Accurate Identification of Harmonic Impedance of Traction Power Supply Systems Considering Harmonic Lateral Propagation

The harmonic impedance of traction power supply systems (TPSSs) is a crucial parameter in identifying, preventing and suppressing high-order harmonic resonances. This article proposes a TPSS harmonic impedance identification method considering the harmonic lateral propagation between two adjacent feeding sections. An operation mode determination method and an improved mean shift clustering are presented, eliminating background harmonic effects and ensuring identification accuracy. Comparative simulations reveal that the proposed method achieves superior performance than conventional methods even if the ratio between load- and source-side impedance fluctuates. Experimental results from a scaled-down laboratory prototype further validate the effectiveness and feasibility of the proposed method.