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Abstract.Fully electric cars will be increasingly used in the near future in many countries. They are commonly known as electric vehicles (EVs) and use power electronic-based rectifiers for charging their batteries, which may significantly impact power quality in LV and MV distribution grids. Of particular importance are harmonic emissions of EV chargers, which are strongly influenced by the distortion of the supply voltage. This paper presents the results of testing and analyzing harmonic current emission of eight different single-phase EV chargers, with respect to supply voltage distortion. The analysis is based on extensive measurements performed at a test stand, capable of accurately reproducing supply voltage waveforms with desired distortion. The harmonic model consists of a constant part and a part that depends on the level of harmonics in the supply voltage. In order to characterize each EV charger in a general model, some characteristic indices are introduced, which quantify the sensitivity and linearity of harmonic currents of EV chargers to harmonics present in the supply voltage. The paper presents and discusses results for each individual EV charger, as well as a comparison of them.

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This paper is the first part of a two-part series on the development of aggregate frequency domain models of PV inverters (PVIs). The developed PVI models are expressed in the form of harmonic admittance matrix (HAM) of a coupled Norton model, also known as the harmonic fingerprint model (HFM). The development of accurate measurement-based HFMs requires considerable amount of measurements, which further increase in case of PVIs, as they typically exhibit strong powerdependent changes in harmonic emission. The authors propose a novel approach, which significantly reduces the number of measurements, as it requires only two sets of measurements at a single operating power: one with the fundamental voltage component, and another with individual voltage harmonics added one by one to the fundamental component. These two sets of measurements are used to calculate a "reference HAM", which is then multiplied by two coefficients calculated from the power-dependent changes of the PVIs total subgroup current harmonic distortion, THDS I . The presented methodology is illustrated and validated using a comprehensive laboratory tests with three different PVIs and it can be easily applied to other types of power electronic devices with similar characteristics.

This paper presents and discusses some initial results of the measurement and assessment of the harmonic characteristics of electric vehicle (EV) chargers and photovoltaic (PV) inverters, which are tested individually and when connected in different combinations to the same phase of a programmable three-phase LV supply in the laboratory. The range of possible harmonic interactions is assessed for three source impedance values and three characteristic supply voltage waveforms. The presented results can help in understanding how the exchange of energy between the grid, power electronic loads (EV chargers) and inverter-interfaced distributed generation (PV inverters) could be assessed in terms of the anticipated "smart grid" transformation of electricity networks.Index Terms-electric vehicle (EV) charger; harmonic emission, interaction, cancellation and attenuation; photovoltaic (PV) inverter; power electronic equipment.