Research On Radio Interference Of UHV Hybrid AC/DC Transmission Lines

With the increasing use of EHV and UHV transmission lines, the electromagnetic pollution caused by corona discharge is becoming a serious problem. One of the most important electromagnetic effects of corona activity of the transmission line is the radio interference. Prediction of the radio interference caused by corona is of great importance for the design of the transmission lines.There are mainly two methods for the prediction of the radio interference, one is the empirical formula and the other is based on the excitation function. Usually, these two methods are applied to different fields. The excitation function method is mainly used in UHV transmission lines. This paper elaborates the principles and calculation procedure of the excitation function method, and the factors that may influence the calculation result are analyzed.Prediction of radio interference of transmission lines is a complex nonlinear problem, so this paper adopted the BP neural network. Through modeling of the radio interference generated by the AC transmission lines, the BP neural network can predict the radio interference successfully.Nowadays, it's too expensive to obtain new right-of-way for the transmission line, so the HVAC and HVDC transmission lines in same corridor is a better way to expand the capacity of an existing corridor. However, this hybrid corridor brings new challenge for the calculation of radio interference. Based on the research of the excitation function method and the experience formula, this paper proposes a new method for the prediction of the radio interference of the hybrid corridor. After the radio interference of the AC/DC transmission lines in same corridor or in same tower is analyzed, some suggestions about the configuration of the hybrid corridor is provided.