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An Online Thermal Deicing Method for Urban Rail Transit Catenary

The frequent icing of a catenary in cold areas has seriously affected the normal operation of urban rail transit. Among many deicing methods for catenary, the thermal deicing method that uses current Joule heat to melt ice has been widely adopted due to its efficiency and safety. However, most of the thermal deicing methods are only applicable when the line is out of service, which cannot solve the icing problem of catenary during the operation period. In order to solve this problem, this article proposes a novel online thermal deicing method that takes the catenary of up and down lines as the deicing current loop. Based on the Bolsdorf theory, the deicing and anti-icing current of catenary are calculated, and the structure and control strategy of the deicing power unit (DIPU) are designed. The influence of online deicing on the traction power supply system is quantitatively analyzed by the electric network model. The accurate dynamic simulation model of the traction power supply system, including the DIPU, is established to verify the analysis conclusion. The results show that the online thermal deicing method has limited influence on the traction power supply system but achieves good deicing performance in the normal operation of the line.