Online detection device for local discharge of high-voltage cable for high-speed railway locomotive

The invention discloses an online detection device for local discharge of a high-voltage cable for a high-speed railway locomotive. The online detection device comprises a control console, a local discharge instrument, a testing transformer and a voltage regulator, wherein the input end of a double-shielding isolation transformer is connected with a 380V power supply; the output end of the double-shielding isolation transformer is sequentially connected with the voltage regulator, a low-voltage filter and the testing transformer; the testing transformer is connected with a filter inductor through a lead; the filter inductor is respectively connected with a capacitive voltage divider and a calibration capacitor through high-voltage leads; the control console is connected with the voltage regulator through a control cable and is connected with the testing transformer through a current measuring wire; the control console is connected with the capacitive voltage divider through a coaxial cable; and the local discharge instrument is respectively connected with the testing transformer, the capacitive voltage divider and the calibration capacitor through the coaxial cable. According to the online detection device, the interference of the local discharge background is reduced below 10pC, the accuracy in measurement is realized and safe and normal running of a high-speed railway can be ensured.