Investigation of severity of voltage flicker caused by second harmonic

Abstract

Second harmonic produces asymmetrical waveform which leads to fluctuation of root-meanssquare (rms) value with certain frequency. Meanwhile, function of weighting filter in flickermeter is designed for sixth-order low-pass filtering function with frequency to be limited to 35 Hz, signal with frequency ranging from 35 to 100 Hz, at certain gain, still can pass through. Since the second harmonic produces fluctuation of rms value with 50 Hz, there is high possibility that it can be passed by this filter and thus resulting in flicker detection. Therefore, this study points out a worthwhile research gap to justify that the presence of the second harmonic can directly increase severity of voltage flicker. In addition, further simulation work using semi-converter has been carried out, as one of main even harmonic sources, in order to justify the concept. To practically validate the concept, Fluke power analyser 435 series II and programmable alternative current source are utilised in the experimental setup. In the main finding, it is confirmed that severity of the voltage flicker increases directly with the presence of the second harmonic and it also formed a clear relationship between short-term perceptibility (Pst) and percentage of the second harmonic component.

Effective low‐cost solution using cascaded connection of two modified notch filters to mitigate the second and third harmonic currents in single‐phase dual‐stage half‐bridge microinverter

“…2 c , the amplitude of the second‐order harmonic current depends on the difference between and . According to [30–32], the tolerance of an aluminium electrolytic capacitor is practically determined as from its specified value. In the worst‐case investigation in this paper, a 40% difference is considered; consequently, the IEEE 1547 standard is not satisfied because of the excessive second‐order harmonic current.…”

“…Additionally, based on half-bridge topology, the inequality between the average voltage values across the two dc-link capacitors or the difference between the two capacitances [5] causes a line frequency ripple voltage on the dc-link, resulting in the appearance of a second-order harmonic current. This grid-injected second-order harmonic current causes asymmetrical sinusoidal voltage waveforms in electrical power systems [26][27][28][29] as well as a voltage flicker [30]. These phenomena have undesirable effects on the electrical load in an electrical system, such as core losses in electrical machines or the saturation of an inductor or transformer.…”

Realtime IoT based Harmonics Monitoring System Review with Potential Low-Cost Devices with Experimental Case Study

“…The measurement of harmonic usually uses harmonic analyzer like in Goh's research, etc. [10]. The harmonic analyzer has some lacks which are expensive, hard into integrated into the SCADA system, and cannot be used to monitor long distances in real-time [11].…”

New flickermeter sensitive to high‐frequency interharmonics and robust to fundamental frequency deviations of the power system

“…It was indicated that there is a significant relationship between the second harmonic magnitude and the P st value and that IEC flickermeter is not capable of measuring it [16]. This is also a major drawback in the measurement of voltage flicker caused by interharmonics.…”