Due to the increase in electronic loads such as LED lamps, power supply units for computing loads, voltage frequency drives in industries; high-frequency distortion is introduced into the power system. These high-frequency components appear due to the switching components of different power electronic converters present in the mentioned loads. The switching frequency components are most often in the range of 2 kHz to 150 kHz referred to as supraharmonics. The paper aims to show, with simulations and measurements, how supraharmonics sum in neutral and to quantify the neutral supraharmonic current as a ratio of single-phase current. This paper defines characteristics of supraharmonic emission that influence their summation in the neutral conductor through studies of devices connected in a balanced three-phase four-wire system. The paper further defines the relation of the supraharmonics emission with the number of devices connected at each phase. A mathematical model to predict the supraharmonics in a neutral conductor based on single-phase current and the number of devices is further proposed.

中文翻译：

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三相四线制中性点次谐波求和


由于LED灯、计算负载的电源装置、工业中的电压频率驱动器等电子负载的增加；高频失真被引入到电力系统中。这些高频分量的出现是由于上述负载中存在不同电力电子转换器的开关组件。开关频率分量通常在 2 kHz 至 150 kHz 范围内，称为超谐波。本文旨在通过仿真和测量来展示中性线中的高次谐波如何求和，并将中性线高次谐波电流量化为单相电流的比率。本文通过对平衡三相四线系统中连接的设备的研究，定义了影响中性导体中的超谐波发射的特性。论文进一步定义了超谐波发射与每相连接设备数量的关系。进一步提出了基于单相电流和器件数量来预测中性导体中的次谐波的数学模型。