Assessment of harmonic distortion levels in LV networks with increasing penetration levels of inverter connected embedded generation

The paper presents a new simulation based method for harmonic distortion level evaluation at the point of common coupling in power system distribution networks. The proposed method aims to calculate the anticipated levels of voltage and current distortion by performing comparative simulation studies based on the information on the existing power quality profiles and the planned future network configuration including inverter connected embedded generation. Time domain simulation is used in order to calculate current and voltage waveforms which then can be analysed with FFT algorithm. The paper gives a detailed explanation of the method followed by the case study performed on a fragment of an actual LV distribution network. In order to provide a holistic assessment of harmonic distortion weekly profiles are analysed in 10 minute intervals which is consistent with the approach proposed in the European standard EN 50160.