Zulkurnain Abdul-Malek
Universiti Teknologi Malaysia

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AC Interference on Gas Pipeline due to Phase to Ground Faults in Overhead Transmission Line Ali I. El Gayar; Zulkurnain Abdul-Malek
International Journal of Electrical and Computer Engineering (IJECE) Vol 6, No 3: June 2016
Publisher : Institute of Advanced Engineering and Science

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (889.583 KB) | DOI: 10.11591/ijece.v6i3.pp1363-1370

Abstract

The purpose of this research is to investigate the severity of voltages induced on gas pipeline installed in parallel to a 115 kV overhead transmission line. The overhead transmission line (OHTL) is configured as a single-circuit. One of the phases exposed to single phase to ground fault. Transmission of high voltage along the same right of way (ROW) with metallic conductor may possibly introduce interference on metallic conductors such as gas pipeline (GPL) due to power frequency voltage as well as due to phase faults and switching phenomena. Two main approaches were used to compute the induced voltages, namely the method of moment (MOM), which is based on electromagnetic field theory, and circuit based method. The simulation considers the length of OHTL and GPL are 30 km and 10km respectively. The pipeline buried at 1 m underground in homogenous earth structure with various soil resistivites ranged from 10 to 1000 Ω-m. The transmission line consists of 150 towers and 200 m span length. The separation distance between the GPL and OHTL is varied from 5 to 100 m. The phase to ground fault current changed from 0.5 to 10 kA. Several observation points are made throughout the corridor, to examinant the induced voltages at different locations. The result show that, the soil resistivity, separation distance, and fault current had significant effect on pipeline induced voltage. In case of the observation points lying on the soil or on the outer surface of the pipeline coating, the induced voltage increased, when the soil resistivity increase, as expected. In case of the observation points placed inside the pipeline metal, and the pipeline is well coated, the induced voltage will decreased, when the soil resistivity increase.
Integration of Frequency Dependent Soil Electrical Properties in Grounding Electrode Circuit Model Mehrdad Mokhtari; Zulkurnain Abdul-Malek; Chin Leong Wooi
International Journal of Electrical and Computer Engineering (IJECE) Vol 6, No 2: April 2016
Publisher : Institute of Advanced Engineering and Science

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (15.881 KB) | DOI: 10.11591/ijece.v6i2.pp792-799

Abstract

The effect of frequency dependent soil properties on the impedance and transient response of the grounding electrode was investigated. The frequency dependent soil models as proposed by Scott, Smith-Longmire, and Visacro-Alipio were critically reviewed. A novel method was proposed to integrate the frequency dependent soil electrical properties in the circuit model of grounding electrode. To validate the application of the method in circuit model, the voltage responses of the grounding electrode obtained by the circuit and electromagnetic models were compared. The voltage responses obtained by the circuit and electromagnetic models were in excellent agreement in terms of voltage peaks and wave shapes. The differences between voltage peaks obtained by the circuit and electromagnetic models were found less than 1%.
Statistical Analysis on Preliminary Breakdown Pulses of Positive Cloud-to-Ground Lightning in Malaysia Chin-Leong Wooi; Zulkurnain Abdul-Malek; Noor Azlinda Ahmad; Mehrdad Mokhtari; Behnam Salimi
International Journal of Electrical and Computer Engineering (IJECE) Vol 6, No 2: April 2016
Publisher : Institute of Advanced Engineering and Science

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (13.982 KB) | DOI: 10.11591/ijece.v6i2.pp844-850

Abstract

This aim of this paper is to study the preliminary breakdown pulses (PBP) of positive cloud-to-ground (+CG) lightning flashes in Malaysia. There is a difference in PBP characteristics when a comparison is made between positive and negative flashes. To the best of the authors’ knowledge, this is the first time the PBP characteristics preceding positive lightning in Malaysia are reported. This study was carried out in Johor Bahru, Malaysia using a broadband antenna system during a monsoon period (Oct-Dec, 2012). It is found that the PBP for +CG lightning is much more complicated compared to the positive cloud-to-ground (–CG) lightning since only negative PBP trains are usually present in the –CG lightning.  Out of 21 analyzed positive flashes, four types of PBP trains were identified according to their initial polarities. These are negative PBP (20%), positive PBP (15%), PBP with polarity reversal (10%), and PBP with irregular polarity (15%). The balance 40% of flashes are without any PBP. The effect of geographical region may also cause the observed differences in the cloud discharge processes including the types of PBP. More studies are needed to determine the relationship between the return stroke and PBP.
Induced Voltages on a Gas Pipeline due to Lightning Strikes on Nearby Overhead Transmission Line Ali I Elgayar; Zulkurnain Abdul-Malek
International Journal of Electrical and Computer Engineering (IJECE) Vol 6, No 2: April 2016
Publisher : Institute of Advanced Engineering and Science

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (293.702 KB) | DOI: 10.11591/ijece.v6i2.pp495-503

Abstract

The purpose of this paper is to investigate the severity of lightning induced voltages on a gas pipeline installed in parallel with overhead transmission line using two different simulation packages. The results from this study using CDEGS, which solves a given problem based on electromagnetic computations, reveal that the induced voltages on the pipeline are more accurate compared to that obtained by PSCAD simulation, which is based on the circuit approach. Unlike PSCAD, CDEGS considers many salient factors such as soil model, inductive, capacitive and conductive couplings, and multiple soil structures.  Models of a double circuit 132kV transmission line, gas pipelines, soil with different resistivities and variable lightning surges were developed. The effects of pipelines located at various heights above ground and distance of pipeline from the power lines were also studied. Compared to previously published work using PSCAD, it is found that CDEGS has given more accurate results. Several findings which were not possible using PSCAD were observed such as the effect of soil structure on induced voltage and multiple layers soil. This also led to better understanding of the conductive coupling from lightning strikes and fault conditions. The modeling work using CDEGS not only useful for providing more reliable data for further protection and mitigation techniques, but is  also very versatile to study the effects of various other important factors affecting the induced voltage on the pipelines. 
Power transmission lines electromagnetic pollution with consideration of soil resistivity Ali Elgayar; Zulkurnain Abdul-Malek; Ruqayyah Othman; Ibtihal Fawzi Elshami; A. M. Elbreki; Visa Musa Ibrahim; Mohammed Imran Mousa; Chin-Leong Wooi
TELKOMNIKA (Telecommunication Computing Electronics and Control) Vol 17, No 4: August 2019
Publisher : Universitas Ahmad Dahlan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12928/telkomnika.v17i4.12771

Abstract

The alternating current (AC) total interference of power lines may pose a threat to personnel and equipment in its vicinity. The main objective of this work is to determine the electromagnetic distribution and induced voltages on human body, equipment, and houses due to the AC total interference for different soil resistivities. The electromagnetic field and induced voltages may cause health problems to the human body and put it at risk. Two main approaches were used to compute the electromagnetic and induced voltages, namely the field approach, which is based on electromagnetic field distribution, and the circuit approach, which uses the circuit grounding analysis to compute the conductive interference and then uses the circuit based models to compute the inductive interference. Human body, steel houses and 10-km-long transmission line were modelled. The soil resistivity was varied, and the induced voltages obtained from both approaches were compared. Soil resistivity and soil structure are important parameters that affect the AC interference level. The results show that the touch voltage increases when the distance between electromagnetic source and human body increases. For high soil resistivity, the danger of the touch voltage becomes more prominent compared to that for low soil resistivity. Power system voltage level and soil resistivity are two key factors influencing the induced voltage level.
Lightning generated electric field over land and sea at Northern Region of Peninsular Malaysia: Measuring Setup Ahmad Muhyiddin Yusof; Zulkurnain Abdul-Malek; Chin-Leong Wooi
Indonesian Journal of Electrical Engineering and Informatics (IJEEI) Vol 8, No 3: September 2020
Publisher : IAES Indonesian Section

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.52549/ijeei.v8i3.1273

Abstract

Lightning is the transfer of significant charge between two charged object, it can appear between cloud-to-cloud, cloud-to-air and cloud-to-ground. All lightning activities are correlated with charge movement and therefore, it can be studied using measurement of electrostatic field (slow field changes), radiation field (fast field changes) and magnetic field affiliated with charge movement. The measuring equipment was a parallel flat plate and vertical whip antenna with an analog filter buffer circuit, connected to a digital high speed oscilloscope. In principle, both antenna have a similar measuring operation, with the exclusion of the antennas dimension, mode of transient recoder and the association of circuitry characteristic (decay time constant). This measurement setup are commonly used to perform electric field characterization related to various lightning events such as as preliminary breakdown, stepped leader, return stroke, subsequent return stroke, dart leader, dart-stepped leader, narrow bipolar pulses and cloud activity between strokes, such as regular pulse trains, K and M changes and chaotic pulse trains. The measurement systems are located very close to the sea, with respect in obtaining a perspicuous explaination of lightning propagation effects on sea instead on land. Noise-distorted effects in data captured usually introduce in a noisy environment or when the lightning strike far from the measurement station, thus the data gathered from the measurement need to be filter using MATLAB computer simulation before conducting further analysis. A promising wavelet 1-D technique, then, were used in signal denoising process rather using conventional filtration. In this works, the state of art in measuring vertical component of electric field focalized sea area during the thunderstorm days been demonstrate and explained.
Status Review on Gas Insulated Switchgear Partial Discharge Diagnostic Technique for Preventive Maintenance Visa Musa Ibrahim; Zulkurnain Abdul-Malek; Nor Asiah Muhamad
Indonesian Journal of Electrical Engineering and Computer Science Vol 7, No 1: July 2017
Publisher : Institute of Advanced Engineering and Science

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.11591/ijeecs.v7.i1.pp9-17

Abstract

Gas insulated switchgear (GIS) plays a vital role in high voltage transmission of electrical energy due to its advantages of high reliability and performance, compact in dimensions and outstanding compatibility with the environment. It uses sulphur hexafluoride gas as its insulant and coolant because of its high dielectric strength and excellent arc quenching ability. Gas insulated switchgear in operation suffers the challenge of its insulation decomposition and eventually failure due to the activities of partial discharge that arouses from defects. This failure is catastrophic and it will lead to entire power out stage that will affect all categories of human activities, so there is a need for Gas insulated switchgear condition monitoring and diagnoses in order to carry out preventive maintenance. This paper reviews diagnostic techniques and methods for Gas insulated switchgear insulation degradation caused by partial discharge for the purpose of carrying out preventive maintenance to avert its failure.
Chemical by-Product Diagnostic Technique for Gas Insulated Switchgear Condition Monitoring Visa Musa Ibrahim; Zulkurnain Abdul-Malek; Nor Asiah Muhamad
Indonesian Journal of Electrical Engineering and Computer Science Vol 7, No 1: July 2017
Publisher : Institute of Advanced Engineering and Science

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.11591/ijeecs.v7.i1.pp18-28

Abstract

Chemical by product diagnostic technique is an efficient, cost-effective and reliable diagnostic technique for gas insulate switchgear condition monitoring in view of its high sensitivity and anti- internal and external electromagnetic interference and noise. In this research paper, coaxial simulated gas insulated switchgear chamber and four different types of artificial defect were designed to cause partial discharge that will simulate the decomposition of sulphur hexafluoride gas in the chamber when energize. Fourier transform infrared spectrometer was used as the method of chemical by-product technique to detect the SF6 decomposition product and its concentration. Different numerous by-products were detected (SO2, SOF2, SO2F2, SO2F10, SiF4, CO, C3F8, C2F6 ) under this experiment using four different types of defect and the by-products differs with the type of defect and the generation rate. Gas insulated switchgear health condition can be feasibly diagnosed by analyzing the decomposition products of SF6 to identify its fault. 
Conductive and Inductive Coupling between Faulted Power Lines and Buried Pipeline by Considering the Effect of Soil Structure Ali I. El Gayar; Zulkurnain Abdul-Malek; Mohammed Imran M; Chin Leong Wooi; Ibtihal Fawzi Elshami
Indonesian Journal of Electrical Engineering and Computer Science Vol 5, No 3: March 2017
Publisher : Institute of Advanced Engineering and Science

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.11591/ijeecs.v5.i3.pp656-660

Abstract

The AC total interference of faulted power lines to gas pipelines sharing the same right of way, which may pose a threat to operating personnel and equipment, was studied. The main advantage of this work is to determine the effects of different soil structures on the induced voltage for various soil resistivities. Two main approaches were used to compute the induced voltages, namely the method of moment (MOM), which is based on electromagnetic field theory, and the circuit based method, which uses the circuit grounding analysis to compute the conductive interference and the circuit based models to compute the inductive interference. A 10-km-long parallel pipeline-transmission line model was developed. The soil resistivity was varied, and the induced voltages obtained from both approaches were compared. Soil resistivity and soil structure are important parameters that affect the AC interference level. The results of the study show that the earth potentials and the metal GPRS are independent. Higher soil resistivity causes the tower ground resistance to increase, thus making the shield wire’s attractiveness as a fault current return path to increase, which in turn forces the induced net EMF and the cumulative GPR in the pipeline to reduce.
Artificial Neural Network Application for Thermal Image Based Condition Monitoring of Zinc Oxide Surge Arresters Novizon Novizon; Zulkurnain Abdul-Malek; Aulia Aulia
Indonesian Journal of Electrical Engineering and Computer Science Vol 7, No 3: September 2017
Publisher : Institute of Advanced Engineering and Science

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.11591/ijeecs.v7.i3.pp593-605

Abstract

Manual analysis of thermal image for detecting defects and classifying of condition of surge arrester take a long time. Artificial neural network is good tool for predict and classify data. This study applied neural network for classify the degree of degradation of surge arrester. Thermal image as input of neural network was segmented using Otsu’s segmentation and histogram method to get features of thermal image. Leakage current as a target of supervise neural network was extracted and applied Fast Fourier Transform to get third harmonic of resistive leakage current. The classification results meet satisfaction with error about 3%.