Charged detection method for insulator of high voltage direct current transmission line

The present invention belongs to the field of electric power transmission, and is especially live detection method of synthetic insulator fault and zero value insulator in high voltage DC power transmission line. The detection method includes the steps of: detecting the AC harmonic electric field distribution around the insulator; comparing with standard electric field distribution; and judging whether the insulator is normal or in fault based on whether to have obvious difference between the two distributions. The present invention facilitates the detection of insulator in high voltage DC power transmission line with voltage level as high as 500 KV and has relatively high sensitivity.