A Study on Lightning Surge Protection Measures for Low Power AC to DC Converter

This paper presents lightning surge protection measures to protect devices damaged by lightning surges flowing into a low power AC to DC converter. Firstly, the paths of low-frequency and high-frequency surge currents are analyzed when lightning surges are applied to the line and ground of the low power AC to DC converter. Based on the analysis of low frequency and high frequency surge current paths, this paper proposes lightning surge protection measures to protect the coupling capacitor between the primary ground and secondary ground sides, Y-capacitors, semiconductor devices, and an IC controller damaged by lightning surges flowing into a low power AC to DC converter. It also proposes a lightning surge protection measure that utilizes a spark gap of a new pattern structure, which has excellent characteristics in reducing lightning surges without additional surge protection devices. Finally the effectiveness of the theoretical analysis of the lightning surge protection measures proposed in this paper was verified through theoretical analysis using the PSIM simulation tool and experimental results.