Field detection device and method for flexible direct-current power transmission converter valve sub-module

The invention discloses an on-site detection device and method for a flexible direct-current power transmission converter valve sub-module, wherein the device mainly comprises a detection box, the bottom surface of the interior of the detection box is fixedly connected with two first separation plates, the two first separation plates are T-shaped, three placement regions are formed between every two first separation plates, and through grooves are formed in the two sides of the bottom end of the outer surface of each first partition plate. The device has the advantages that a control processing part, a capacitance and inductance detector and a voltage monitor are arranged at the bottom end of the interior of the detection box, meanwhile, a placement box is arranged at the top end of the interior of the detection box, a sponge layer is arranged in the placement box, and a handheld display part is arranged in the sponge layer; the capacitance and inductance detector and the voltage monitor are respectively conn