Method for determining turn-to-turn short circuit, two-phase short circuit and single-phase short circuit of parallel reactors

The invention discloses a method for determining the turn-to-turn short circuit, two-phase short circuit and single-phase short circuit of parallel reactors, which comprises the following steps: (1) calculating a fault component delta*2 of a negative sequence voltage according to measurement; (2) calculating a fault component delta*2 of a negative sequence current according to measurement; (3) substituting the delta*2 and the delta*2 into a formula (A) expressed as the absolute value of (delta*2-jdelta*2XL2) is more than or equal to the absolute value of (delta*2+jdelta*2XS2), wherein the formula (A) is an operational equation of a voltage absolute value comparison type negative sequence directional relay, and in the formula, XL2 represents the negative sequence reactance of the reactors and XS2 represents system negative sequence reactance; and (4) if the formula A is valid, determining that parallel reactors having ungrounded neutral points have an internal turn-to-turn short circuit or two-phase short circ