Effects of Supraharmonics Immunity Testing on LED Lighting

摘要

With the advent of distributed energy resources (DERs) and proliferation of single-phase consumer loads based on power electronics, the problem of voltage and current distortion due to frequencies in the range 2 to 150 kHz (also known as supraharmonics) is becoming more and more common. In order to assess the impact of such grid changes on end use load in the United States (US), a multiple year project was launched by the Electric Power Research Institute (EPRI). This paper presents select results from this project, involving LED based lighting commonly sold in the US consumer market. Although LED lamps themselves have been shown to be sources of supraharmonics emission, the results in this paper show that under certain conditions, the presence of supraharmonics in applied voltage can lead to the production of visible flicker from such lamps. Furthermore, during testing, audible noise was also observed to be emanating from some of the lamps. The results confirm and agree with the results of similar tests conducted in Europe. In contrast to previous studies however, a light flickermeter specified in IEC 61457 was used in these tests so that the results could be quantified in a format familiar to most Power Quality engineers. In addition to informing knowledge of supraharmonics emission at the utility level, the results shown in this paper are intended to guide and inform active discussion on the subject of supraharmonics and flicker in IEEE standards committees, where two active PARs on these subjects are currently under discussion and deliberation.