Non-contact detection method for wire power-off and power-on events

The invention discloses a non-contact detection method for wire power-off and power-on events. The non-contact detection method is used for power-off and power-on detection analysis of the downstream of a middle and low voltage line; the low-cost and effective non-contact power-off and power-on event detection can be realized. The method comprises the following steps: (1) sampling a current I and a voltage V of a wire; (2) according to the sampled current I, the sampled voltage V and three continuous time periods T[0], T[1] and T[2], obtaining the state S of the wire at the time period T[0]; and (3) calculating to obtain average voltages V[-T1] and V[-T2] and average currents I[-T1] and I[-T2] corresponding to the two continuous time periods T[1] and T[2], judging whether the conditions that the average voltages and the average currents are greatly reduced and the wire is in an electrified state simultaneously occur or not according to the average voltages V[-T1] and V[-T2] and the average currents I[-T1] and