Advances in Protection Technology Against Reradiation Interference on Radio Stations from Power Lines

Background: Reducing Reradiation Interference (RRI) on radio stations from adjacent UHV power lines is one of the key issues urged to be solved in UHV power projects undergoing in China. Methods: In this paper, advances in three aspects, namely the mechanism of RRI, distance-based protecting measures and detuning-based protecting measures are introduced. Combining with the up-to-date studies on induced current and resonance for RRI in MW frequency band, we analyzed and summarized the efforts in the three aspects. Conclusion: It is concluded that the key issue in RRI protection is to clarify the resonance mechanism as well as the determining factor of RRI. Since the researches from IEEE were mainly based on field intensities, they cannot obtain resonance mechanism for RRI at frequencies above 1.7 MHz, which resulted in the ignorance of resonance in protecting distance calculation in China that induced exaggeration in the distance. Plus, the protecting distance cannot deal with the RRI problems at SW and above frequency bands already existed in China. Therefore, it is suggested to apply the generalized resonance theory or other novel methods to determine the resonance mechanism of RRI at SW and above frequencies.