Simulation of Overvoltage in Photovoltaic Energy Storage System Caused by Lightning Strike

The photovoltaic energy storage system (PESS) plays an important role in addressing energy dependency issues and promoting the transformation of energy structures. However, lightning strike is one of the main causes of damage to PESS, posing serious threats to its safe operation. This paper constructs a PESS transient model by using PSCAD/EMDTC simulation software to investigate this issue. The distribution of lightning overvoltage in the PESS is calculated. The influence of different lightning strike locations and types on the overvoltage levels of PESS is analyzed. Based on the analysis, lightning protection measures are proposed. The results indicate that when the grid side of the PESS is struck by lightning, the peak overvoltage of the transformer is higher than that when the photovoltaic side is struck. In the case of direct lightning strike, the photovoltaic side can generate a lightning overvoltage with the amplitude of 270.3 kV. The installation of lightning protection equipment effectively suppresses overvoltage.