Experimental Investigation on Live Working Requirements for 1000kV Ultra High Voltage AC Transmission Line

To provide technical support and reference for the design and maintenance of 1,000 kV AC transmission line, the experimental investigation on live working was carried out systematically. First, according to the system parameters, the over-voltage level and its statistical distribution during the process of live working were analyzed and calculated. And then, at 1:1 ratio scale simulated tower, tests were performed on different live working positions. Based on these, the minimum approach distance and complex gaps were obtained, and the minimum effective insulating length of insulating tools was found too. According to the practical conditions of the lines, suitable full-set screening clothes were developed and tested. And the electric field intensity on human-body surface inside and outside of the screening clothes at different working positions was measured. The results indicate that the climbing worker should dress screening clothes, and the equal potential worker should wear additional electric field shield mask, and use potential rod during the equal potential process.