Broadband online measurement sensor for DC extra-high voltage corona current

The invention relates to a broadband online measurement sensor for DC extra-high voltage corona current, which comprises an isolation electrode unit, a signal processing unit and a system power supply unit, wherein the isolation electrode unit comprises an insulated isolation sleeve, a hollow tubular long arm low-voltage electrode and a hollow tubular short arm high-voltage electrode, wherein two ends of the insulated isolation sleeve are respectively in security isolation connection with the high-voltage electrode and the low-voltage electrode in a special way; the signal processing unit consists of a sampling resistor module, a signal acquisition module, a signal conversion module and a signal transmission module; the system power supply unit comprises a storage battery pack and a charging module; and the signal processing unit and the system power supply unit are arranged in the isolation electrode unit, so that the high-accuracy integral measurement sensor can be formed. The broadband online measurement sensor solves the problems of shielding disturbance of a strong electric field between an acquired signal and an acquisition channel as well as surrounding stray capacitance, and realizes the broadband domain online measurement and the multi-point network online measurement of the DC extra-high voltage corona current.