Impact of Harmonics above the 50th Order on the Industrial Grid due to Charging of Electric Vehicles in an Employee Parking Lot

Abstract:
Climate protection is an essential part of the 21st century. The transformation of the transport sector enables the reduction of CO2 emissions through the use of climate-friendly fuels and types of drive. Battery electric mobility plays an important role in this context. With the increasing number of electric vehicles, a widely expanded charging network is needed. In addition to private charging options at home, semi-public employee parking lots at the employer are predestined for the development of charging infrastructure due to the long parking and thus charging time. In most cases, the charging points are supplied from an industrial grid that is already subject to harmonics. The electric vehicle adds a new source of harmonics, whose impact is largely unknown in the industrial grid. Previous studies have already shown that electric vehicles generate harmonics, especially in the higher order range. However, there are no findings showing the impact of charging electric vehicles in an employee parking lot on the industrial grid in a range above the 50th harmonic order. In this context, the actual state regarding harmonics in the industrial grid is determined up to the 200th harmonic order using measurement data from the automotive industry, and the respective worst-case time is determined. Afterwards, these worst-case times are integrated based on an existing industrial grid in the grid calculation program DIgSILENT PowerFactory. Based on an existing worst-case scenario with battery electric vehicles (BEV), whose measurement data are also integrated, the impact on the industrial grid is analyzed. The focus is on harmonics from the 51st to the 200th harmonic order, for which no firmly defined limit values are yet available in the IEC 610002-4 standard.