The invention relates to an
alternating current electric
transmission line lightning flashover restriction method and device. The method includes the steps of current steering,
voltage limiting and arc blowing-out. The current steering includes the steps of providing a current
discharge channel for
power frequency short-circuit current through a parallel gap, wherein the parallel gap is mounted on both ends of an insulator, the
breakdown strength of the parallel gap is lower than that of the insulator, and
lightning current flows through the parallel gap rather than passing through the insulator when the parallel gap is broken down by
lightning. The
voltage limiting includes the steps of connecting a non-linear
energy absorbing assembly in series with the parallel gap and limiting over-
voltage at both ends of the insulator to prevent the insulator from being damaged by lightning flashover, wherein the non-linear
energy absorbing assembly is used for absorbing lightning current energy on the basis of current steering. The arc blowing-out includes the steps of treating continuous
combustion caused by arc produced in the parallel gap when the
power frequency short-circuit current continues to flow through the parallel gap after lightning current passes to prevent
tripping of a
circuit breaker. The
alternating current electric
transmission line lightning flashover restriction device is composed of the parallel gap, electrodes, the non-linear
energy absorbing assembly and a special-shaped connecting unit which are assembled and connected with one another and is simple in structure, light in weight and small in size.