Optimization Measures for Increased Immunity against High Frequency Disturbances and Reduced Emission in the Range of 2 kHz to 150 kHz Realized on Different LED Lamps

Abstract

In this paper, optimization measures to increase the immunity against high frequency (HF) disturbances by simultaneously reducing the impact on the grid through non sinusoidal input currents in the frequency range of 2 kHz to 150 kHz are presented. Two different light-emitting diode (LED) lamps as an example for typical electronic mass-market products are optimized. Currently, LED lamps are state of the art in the range of efficient lamps. But long-term experiences concerning their immunity against HF disturbances are not investigated so far. In order to assess the additional stress on the built-in components of the LED lamps caused by HF disturbances, the power supplies of two exemplary LED lamps are considered and their input current, the current of the electrolytic capacitor and the current of the LED are depicted. Based on these measurements, the electrolytic capacitor can be identified as one mainly weak point of the LED lamp's power supply. Subsequently, possible measures to increase the immunity of the identified stressed components and the LED lamp by itself are presented. Finally, the overall efficiency of the optimizations and their effect on the grid's power quality are shown.

Supraharmonic disturbances: Lifetime reduction of electronic mass-market equipment by the aging of electrolytic capacitors

“…Especially these circuits with electrolytic capacitors are potentially affected by supraharmonic distortions due to its capacitive impedance behavior. [4], [7] Measurements with supraharmonic distortions of 2 V amplitude have shown that there is an up to doubled ripple current on the circuits' input capacitor [4]. The actual ripple current of the capacitor is highly dependent on the distortion's frequency and the distortion's amplitude.…”

“…So, especially electronic mass-market equipment (LED lamps, USB power supplies etc.) and their built-in components like electrolytic capacitors for voltage smoothing are additionally stressed by these supraharmonic disturbances [4]. As a result, effects like malfunctions or impairments of the equipment have increasingly been noticed within the last few years [5], [6].…”