Supraharmonic and Harmonic Emissions of a Bi-Directional V2G Electric Vehicle Charging Station and Their Impact to the Grid Impedance

Abstract

Bidirectional electric vehicle supply equipment and charging stations (EVSE) offer new business models and can provide services to the electrical grid. The smart grid lab in Vienna gives unique testing possibilities of future smart grids, as different type of electrical equipment can be operated at a reconstructed, well-known distribution grid. In this work the harmonic and supraharmonic emissions of a bidirectional EVSE are measured according to IEC61000-4-7 and IEC61000-4-30 Ed3 standard as well as the high-frequency grid impedance. In addition, the efficiency and the power factor are determined at various operating points. Although THDi at nominal power (10 kW) is very low and the efficiency and power factor is very high, at low power levels the opposite situation arise. Supraharmonic emissions remain stable independent of the charging/discharging power, and both wideband and narrowband emissions occur. The additional capacitance when connecting the EVSE impacts the high-frequency grid impedance substantially and generates resonance points.

Communications and Data Science for the Success of Vehicle-to-Grid Technologies: Current State and Future Trends

“…By contrast, the emissions generated by V2G processes have not yet been widely addressed by the scientific community. Authors in [154,155] analyze the conducted emissions generated by a V2G system at a reconstructed LV grid in Vienna, highlighting the existence of both narrowband and broadband emissions in the 9-150 kHz frequency band, as well as identifying their main cause of occurrence. The waveforms recorded in different conditions of this V2G process have also been used to perform a statistical comparison of CISPR 16-1-1 and LightQP methods [156], CISPR 16-1-1, IEC 61000-4-7, and IEC 61000-4-30 methods [157].…”

Design of a PV‐fed electric vehicle charging station with a combination of droop and master‐slave control strategy

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