Publications 2021

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https://hdl.handle.net/20.500.14170/3707

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Browsing Publications 2021 by Author "Ab Kadir M.Z.A."
  • Publication
    An experimental work on effect of bending down conductor with reinforced concrete
    ( 2020-01-07)
    Amizah Md. Ariffen
    ;
    Syahrun Nizam Md Arshad @ Hashim
    ;
    Ab Kadir M.Z.A.
    ;
    Jasni J.
    ;
    Nasrul Helmei Halim
    Down conductor is one of the pivotal parts of the Lightning Protection System (LPS) that diverting the lightning current captured by the air termination system to the earth termination system in each protected structure. A straight down conductor, is ideally suited for the best-case scenario regarding reliability and safety protection. One to aesthetical aspects, down conductor is undesirably bent in most current buildings. However, only the primary bare type of a down conductor is undergone such process, and bent at a certain degree which depending on the structure itself. Hence, this study is to investigate the bending degree effect on down conductors, by looking at breakdown voltage around the bent area with the presence of concrete wall and reinforcement bar. This experimental work conducted on a reduced scale of reinforced concrete which tested with high impulse voltage. It was determined that the bending down conductors has a significant effect on the bent (vertex) area with the interaction of concrete wall and reinforcement bar.
  • Publication
    Analysis of wavelet transform de-noising technique based on measured lightning return stroke electric field
    ( 2021-05-03)
    Syahrun Nizam Md Arshad @ Hashim
    ;
    Ab Kadir M.Z.A.
    ;
    Izadi M.
    ;
    Hamzah M.N.
    ;
    Amizah Md. Ariffen
    ;
    Wooi C.L.
    ;
    Anuar A.
    This paper presents a difference type of wavelet transform de-noising technique based on measured lightning electric field. The lightning electric fields captured by two parallel plats sensor and the signal were analyses accordingly. In engineering application, lightning stroke current parameter will relate with electric fields and these parameters can be recognized by direct and in-direct measuring method. Therefore, measuring lightning electric fields (LEF) using parallel plate was done by many researchers. However, measuring LEF has many disturbances such as noise from other apparatus and other device. Therefore, de-noising of LEF signal is important to get useful signal for further research. For this reason, the Centre for Electromagnetic and Lighting Protection Research (CELP) group has been working on a research program to study and characteristic lightning using de-noising technique in order to process and analyse the radiated LEF produced during flash happens. Only three types of wavelet transform are selected and there are Daubechies, Symlets and Coiflets wavelet. The result will be discussed and the best will be selected based on the measured signal.
  • Publication
    Automated Negative Lightning Return Strokes Classification System
    ( 2021-12-01)
    Haris F.A.
    ;
    Ab Kadir M.Z.A.
    ;
    Sukhairi Sudin
    ;
    Johari D.
    ;
    Jasni J.
    ;
    Noor S.Z.M.
    Over the years, many studies have been conducted to measure and classify the lightning-generated electric field waveform for a better understanding of the lightning physics phenomenon. Through measurement and classification, the features of the negative lightning return strokes can be accessed and analysed. In most studies, the classification of negative lightning return strokes was performed using a conventional approach based on manual visual inspection. Nevertheless, this traditional method could compromise the accuracy of data analysis due to human error, which also required a longer processing time. Hence, this study developed an automated negative lightning return strokes classification system using MATLAB software. In this study, a total of 115 return strokes was recorded and classified automatically by using the developed system. The data comparison with the Tenaga Nasional Berhad Research (TNBR) lightning report showed a good agreement between the lightning signal detected from this study with those signals recorded from the report. Apart from that, the developed automated system was successfully classified the negative lightning return strokes which this parameter was also illustrated on Graphic User Interface (GUI). Thus, the proposed automatic system could offer a practical and reliable approach by reducing human error and the processing time while classifying the negative lightning return strokes.
  • Publication
    Measurement of Negative Lightning Return Strokes Using a Proposed Small-Scale Parallel Plate Antenna at the Central Region in Peninsular Malaysia
    ( 2021-12-01)
    Haris F.A.
    ;
    Ab Kadir M.Z.A.
    ;
    Sukhairi Sudin
    ;
    Johari D.
    ;
    Hamzah M.N.
    Lightning can occur between the clouds (intra-clouds), ground-to-cloud (CG), and inside the clouds. The lightning strike hazards can be managed appropriately using a lightning detector system consisting of an antenna, buffer amplifier circuit, and a measurement device. In this study, the development and fabrication of small-scale parallel plate antenna were carried out by reducing the physical height and antenna dimension to measure the generated electric fields. The experimental work was conducted at the rooftop of the College of Engineering, Universiti Tenaga Nasional (UNITEN), Selangor, Malaysia, from August 2019 to March 2020. The total number of 115 return strokes (RS) of negative lightning events were recorded during the measurement period. Characterization of seven types of criteria for negative return stroke has been analysed and compared to the existing parallel plate antenna with a similar climate condition and different countries. Based on the comparative study, the proposed and the existing parallel plate antenna shows a good agreement. Hence, the proposed small-scale parallel plate antenna can be used as a portable, lightweight, and easy to install device for the lightning measurement system.