The invention discloses a method and apparatus for eddy-based electronically-controlled scanning and monitoring. The apparatus comprises a plurality of probe support slant blocks, a plurality of
single coil eddy detection probes, an array electronic switching conduction switch, a
programmable logic controller, an eddy detection instrument, a standard detection piece, and a
signal cable. On the basis of an
electromagnet nondestructive detection principle, the plurality of
single coil eddy detection probes are arranged in a line in a pushed domino arrangement mode and are fixed on a detection surface of a detected steel rail. Because of the utilization of an array electronic switching conduction switch technology, only the single-channel eddy detection instrument is needed to receive an eddy
signal without the need of an expensive array eddy detection instrument, thereby substantially reducing the detection cost. Meanwhile, eddy detection coils employ a circular-bead square winding mode and the detection covering surfaces of the multiple eddy detection coils are intersected and superposed with each other, thereby eliminating the detection blind area. Therefore, the provided apparatus is suitable for in-use real-time monitoring work of steel rails like a railway rail and a sliding rail of a port crane and the like in the industries of railway, port, bridge, and building and the like.