Corona Discharge Characteristics for Conductors of HVDC Transmission Lines with Different Heights to Groud

The corona discharge characteristic of the conductor is one of the key factors affecting the electromagnetic environment of the project. In order to obtain corona discharge characteristics of conductors with different heights to ground and correction methods for inception corona voltage of conductors with different heights to ground, corona test were carried out in Ultra-high Voltage Test Base in Wuhan with ultraviolet image apparatus, the corona test of conductors of JL/G1A-1250/100 and JL/G lA-1250/70 at different heights to ground were carried out, one single conductor, 6-bundle conductor with bundle space 500mm and 8-bundle conductor with bundle space 550mm were tested separately. The results show that Under DC positive voltage, the corona inception voltage for conductors increased with the rise of the height to ground, different bundle distances, different bundle conductors and one single conductor corona discharge characteristics have some differences; The corona inception voltage between single conductor and different bundle distances conductors have certain functional relationship. By establishing the functional relationship between them, the corona inception voltage of bundle conductors can be calculated by the corona inception voltage value of a single conductor, the value of correction errors can be controlled at less than 13%.