5 mHz highpass filter with −80 dB total harmonic distortions

This study investigated current harmonic distortions emanating from domestic non-linear loads which have adverse deleterious effects on installed low voltage switchgears such as transformers and conductors. The study examined harmonic distortions emanating from dominant domestic nonlinear loads such as microwave, TV set, radio, fridge, video player and compacted fluorescence bulbs (CFLs) using a power quality equipment. From the results obtained, it was noted that there is need to mitigate harmonic distortions generated by domestic loads at point of common coupling (PCC). It is pertinent to mention that the recent study on supplied loads carried out in Kenya power grid shows that above 67% of power end users are domestic consumers. Under current last mile initiative and Global Partnership on Output Based Aid (GPOBA), unprecedented increase of domestic loads connected to the power grid is predicted. It is worth pointing out that most of these domestic loads have switch mode power supplies (SMPS) which have inherent characteristics of distorting current waveform which causes voltage distortions, over-heating of neutral conductors and premature failure of distribution transformers. Further, most of these loads have two modes; standby/sleep mode and operating mode. Results shows that the two modes generate current harmonic distortions which stream back to power utility network through the service cable. Recently, engineers have designed electronic devices that consume less power. These devices draw current in pulses rather than sinusoidal waveform. As a result, the quality of power supplies continues to deteriorate hence adversely affecting the installed low voltage switchgears such as distribution transformers. Although various mitigation measures exist to reduce the effects of harmonic distortions, this paper proposes a single phase active filter as an optimal solution for attenuating the harmonics emanating from domestic non-linear loads.

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Ultra Wide Band (UWB) 3.4 - 4.8 Ghz Bandpass Filter Menggunakan Saluran Transmisi CRLH Satu Sel

TELKA - Telekomunikasi Elektronika Komputasi dan Kontrol ◽

10.15575/telka.v2i1.8 ◽

2016 ◽

Vol 2 (1) ◽

pp. 18-26

Author(s):

Andika Atmaja

Keyword(s):

Transmission Line ◽

Transmission Lines ◽

Bandpass Filter ◽

Wide Band ◽

Ultra Wide Band ◽

Double Negative ◽

Transmission Line Model ◽

Artificial Material ◽

Left Handed ◽

Highpass Filter

Penelitian studi tentang Metamaterials (MTMs) dalam beberapa tahun terakhir telah meningkat sangat pesat. Metamaterials yang di sebut juga artificial material atau Left Handed (LH) material adalah material yang tidak ada dialam dimana strukturnya direkayasa oleh manusia yang memiliki dua atau lebih properties yang khusus, misalkan pada Double Negative (DNG) material yang memiliki μ negative dan ε negative. Beberapa pendekatan dalam mendesign metamaterial yaitu pendekatan resonant dan pendekatan Transmission line. Model transmision line yang pertama adalah Right Handed Transmission lines (RH TL) yang dimodelkan dalam sebuah unit sel sebagai rangkaian dan shunt kapasitor shunt(CR), yang kedua adalah Left Handed Transmission Line (LH TL) dimodelkan dalam sebuah unit sel sebagai rangkaian kapasitor seri(CL) dan induktansi shunt(LL). gabungan dari dua buah model transmission line ini disebut Composite Right-left Handed Transmission Line(CRLH TL) dan ini menjadi dasar dalam mendesign metamaterial. CRLH transmission line dimodelkan dalam sebuah unit sel sebagai rangkaian kapasitor seri(CL), induktansi seri(LR) dan induktansi shunt (LL) serta induktansi shunt(LL). CRLH TL memiliki negatif, nol dankonstanta propagasi positif sesuai dengan karakteristik dari permitivitas efektif dan permeabilitas[1]. Hasil pengukuran bandpass filter menggunakan saluran transmisi CRLH satu sel menunjukkan frekuensi cutoff pada -10dB terletak pada frekuensi 3.016 GHz pada highpass filter dan 5.359GHz pada lowpass filternya. Sedangkan frekuensi 3.4 GHz terletak pada -4.8415 dB sedangkan frekuensi 4.8 Ghz terletak pada -4.753 dB. Hasil dari perancangan menunjukkan bahwa saluran transmisi CRLH satu sel dapat memenuhi spesifikasi yang diminta.

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Influence of electrodes area ratios and the discharge volume in RF capacitively coupled plasma

Iraqi Journal of Physics (IJP) ◽

10.30723/ijp.v11i20.376 ◽

2019 ◽

Vol 11 (20) ◽

pp. 1-8

Author(s):

Moyad Abdullah Ahmad

Keyword(s):

Glow Discharge ◽

Cone Angle ◽

Experimental Results ◽

Rf Power ◽

Capacitively Coupled ◽

Discharge Volume ◽

Capacitively Coupled Plasma ◽

Harmonic Distortions

Experimental results on harmonic distortions in 13.56 MHz RF Argon glow discharge using different grounded electrodes areas and electrodes spacing are presented. The experiment is carried out at four pressure values. RF power values used are between 20 and 90 watts. The results indicate significant increase in distortions at two specific values of the cone angle enclosing the two electrodes within its geometrical volume. The computation of the cone head angle gave the symmetry discharge or asymmetry as well as when the angle is small the condition is near symmetry discharge associated with decrease in the nonlinearity.

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