Multi-Criterion Fusion Method for Dominant Harmonic Source Determination in Ring Transmission Networks

The power electronization of new-era power systems has led to increasingly severe harmonic distortion in transmission networks. Transmission networks are characterized by ring structures deep coupling of multiple sources, and frequent harmonic resonances, which make it difficult to conduct harmonic source determination. Most existing methods focus on distribution networks, and the implicit assumptions they rely on do not hold in ring transmission networks. To address this issue, this paper proposes a multi-criterion fusion method for dominant harmonic source determination in ring transmission networks. This method presents three criteria including the harmonic propagation characteristic, harmonic power flow direction, and harmonic impedance characteristic based on the equivalent model of ring transmission networks. The measured data and simulation model are used to perform multi-criterion consistency verification, thereby identifying the location of the dominant harmonic source. Through the field case study of a 500 kV ring transmission network, the results show that the proposed method can effectively identify the dominant harmonic source in the ring transmission network according to the collaborative comparison of measured and simulated harmonic characteristics derived from multi-criterion fusion.