Survey of Electromagnetic Interference of ±1100 kV HVDC Project on Communication Network for DC Filter Necessity Research

Nowadays the anti-interference capability of the communication system has developed rapidly, thus the necessity of DC filter in ±1100 kV project should be reconsidered, and the communication net interfered condition should be surveyed. In the research, the communication net structure in China was investigated and the possibly interfered communication media was determined. The Ieq distribution along the DC line was calculated and it was found the Ieq is only large near the rectifier and the inverter. The electromagnetic induced noise voltage calculation method, coefficients and limit were determined. The detailed communication lines distribution was surveyed, the specific induced noise voltage on each communication line was calculated, and therefore the to-be reformed communication lines were determined, providing strong support for DC filter necessity research. The communication net investigation and reformation method can be a reference for other DC project in the world under the new developed-communication technology condition.