Volume 60

Fault Location of New Energy Transmission Lines Based on MultipleFrequency Signal Injection Chenhao Zhang, Yaoyuan Ma, Guobing Song, Ziyang Wang, Qing Wan, Jieyu Chen

Abstract

To address the influence of converter control andtransition resistance on traditional fault-locationmethods for renewable energy export lines, this paperproposes a single-terminal fault location method basedon active injection of complex-frequency signals.Leveraging the controllability of a Static Var Generator(SVG), dual characteristic-frequency signals are injectedimmediately after fault occurrence. Stable injection isachieved through frequency-separation control andconstant-current amplitude regulation. Equivalent faulttopologies at the characteristic frequencies areestablished for both phase-to-phase and single-phase-to-ground faults, from which complex-valued distanceequations are derived. Considering the long-line effects,a distributed-parameter model is further adopted toconstruct dual-frequency distance equations, and theSpider Wasp Optimizer (SWO) is introduced to achieveinitial-value-independent fault distance estimation.Simulation results in PSCAD/EMTDC demonstrate thatthe proposed method exhibits strong robustnessagainst transition resistance and is well-suited for high-accuracy fault location in renewable energy exportsystems.

Keywords New Energy; Fault Location; Single-EndedQuantities; Dual-Frequency Signal Injection