UHV shunt reactor for secondary arc extinction on multiphase reclosing

Secondary-arc suppression is necessary for successful fast, multiphase reclosing on UHV lines. Installation of a shunt reactor is one of the most effective methods of rapidly extinguishing the secondary arc. For multiphase reclosing on untransposed double-circuit UHV lines, a zero-sequence compensated balanced shunt reactor cannot suppress the secondary arc sufficiently. This is because of the imbalance in electrical couplings among phases. A zero-sequence compensated unbalanced shunt reactor is proposed to compensate for the imbalance in the electrostatic couplings. The effects of this reactor on suppressing the secondary arc can easily be analysed by the introduction of phase-to-phase compensation parameters. Such parameters can be used to decide on the optimum shunt reactor for secondary-arc extinction.