Novel AC transformer on-line detection device and method

The invention discloses a novel AC transformer on-line detection device and method. According to the invention, an alternating current inversion module is used for generating alternating current, a cable passes through N transformers to be tested, only one transformer to be tested is controlled to be powered by a power supply routing switch to work, signals of the transformer to be tested are output, and output current value signals of the transformer are conditioned into voltage signals, aligned with the output signal waveform of a standard transformer and then displayed. According to the invention, multiple paths of to-be-detected transformers can be accessed at one time, one path is switched on for detection through path selection, tedious wiring, disconnection and configuration operations are not needed, multi-period waveforms of output signals of standard and detected transformers can be displayed in real time, and the overlap ratio of the standard and detected transformers and the transformer performanc