Underwater array type alternating current electromagnetic field crack detection probe device and system

The invention provides an underwater array type alternating current electromagnetic field crack detection probe device and system. The device comprises a shell; the shell is filled with insulating oil; the shell is provided with a first end and a second end which are perpendicular to each other; a sensor cover is arranged at the first end of the shell; a detection module and a mounting seat are arranged in the sensor cover, and the detection module comprises a data acquisition module and an excitation module; the data acquisition module comprises an acquisition chip set; the excitation module comprises an I-shaped magnetic core and an excitation coil; the I-shaped magnetic core is placed in the groove of the mounting seat, and the excitation coil is wound outside the I-shaped magnetic core; acquisition chips are arranged on one side surface of the lower end surface of the mounting seat and the end surface, back to the I-shaped magnetic core, of the mounting seat; and the second end of the shell is provided wi