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Untransposed extra-high voltage (EHV) or ultra-high voltage (UHV) transmission lines with conventional shunt reactors may cause the secondary arc current difficult to extinguish and result in failure of single-phase auto-reclosing (SPAR).This paper focuses on comparative analysis of different shunt reactor schemes for untransposed transmission line (UTL) in suppressing secondary arc current.Several shunt reactor schemes were introduced at first, followed by the formulation and analysis of secondary arc current for UTL.Taking into account the reactive power requirement of both steady state and transient state, this paper proposed a stepped controllable shunt reactor scheme.Simulation results of 1000-kV test example show that the proposed shunt reactor scheme is effective in suppressing UTL secondary arc current; meanwhile the proposed shunt reactor scheme, the single-phase switched shunt reactor scheme and neutral-switehed shunt reactor scheme are better than the balanced shunt reactor scheme in UTL secondary arc suppression.Moreover, the single-phase-transformer shunt reactor is effective in secondary arc current suppression only with a small neutral reactor.Finally, the application and implementation of different shunt reactor schemes in UTL were discussed.The authors recommend that the proposed shunt reactor scheme is preferred to be applied to longer untransposed single-circuit or double-circuit EHV/UHV transmission line.