Wooi Chin Leong
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Preferred name
Wooi Chin Leong
Official Name
Leong, Wooi Chin
Alternative Name
Wooi, Chin-Leong
Wooi, C. L.
Wooi, Chin-leong
Main Affiliation
Scopus Author ID
55912811600
Researcher ID
V-2268-2019

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  • Publication
    A Smart Image Enhancement Monitoring System Using Graphical User Interface (GUI)
    ( 2020-06-17)
    Sam S.
    ;
    Wan Azani Wan Mustafa
    ;
    Syed Zulkarnain Syed Idrus
    ;
    Mohd Aminudin Jamlos
    ;
    Mohamad Nur Khairul Hafizi Rohani
    ;
    Wooi Chin Leong
    Image filtering is one of the methods used in image processing. It is also can be called as image enhancement. Filter help the problems of the image display and can improvise the quality of the image. The problems that always happened in the image is illumination, noise and under-light images. In addition, these problems also caused a few troubles for image recognition for the daily life of certain people for their work. The purpose of this study is to apply the mathematical algorithm of the filters, identifying the best method of the filters and simulate the result of the image quality assessments in Graphical User Interface (GUI) and Global System for Mobile Notification (GSM). Basically, image processing methods have specific mathematical algorithms. That is the main difference between these methods. For this paper, two types of image have been chosen which is document image and medical image. There were a few methods that were selected in this project. It is a high pass filter, low pass filter, and high boost filter. Thus, homomorphic filtering was applied to that filter. Then, the enhanced images would be simulated to the selected parameters of image quality assessments (IQA). The selected parameter of the image quality assessment is a global contrast factor (GCF) and signal to noise ratio (SNR). If the value of the parameters satisfies its characteristic, the method would be selected as the most suitable method for the image. Meanwhile, the best result will be selected as the best image for this study.
  • Publication
    Analysis on Behavior Grounding Electrode Resistance base on Profiling Method
    ( 2020-07-09)
    Hashim N.H.
    ;
    Syahrun Nizam Md Arshad @ Hashim
    ;
    Halim N.H.
    ;
    Wooi Chin Leong
    ;
    Ariffen A.M.
    ;
    Anuar A.
    ;
    Aqilah Sofiyah Hasni N.
    ;
    Abu Bakar O.
    An earthing system or known as grounding system in an electrical installation where by the grounding system connects specific parts of that installation with the Earth's conductive surface for safety and functional purposes. It is the process of transferring the immediate discharge with the aid of the low resistance wire of the electrical energy directly to the earth. It is really an important role playing in electrical system part as grounding system give protection during fault or lightning occur. In addition, grounding system also give protection for human electrical appliance and building from electrical shocks due to electrical fault or lighting occur. In this research will shows that to identify the best location to install the grounding electrode. This method is used on 10 x 10 meters which is 121 point will be investigated. The result of 0.3m, 0.6m, and 0.9m were analyzed using MATLAB software to produce profiling and shows the perfect location to install the Grounding system electrode.
  • Publication
    Influence of PD source and AE sensor distance towards arrival time of propagation wave in power transformer
    ( 2020-01-07)
    Khairul Nadiah Khalid
    ;
    Mohamad Nur Khairul Hafizi Rohani
    ;
    Baharuddin Ismail
    ;
    Muzamir Isa
    ;
    Afifah Shuhada Rosmi
    ;
    Wooi Chin Leong
    ;
    Yii C.C.
    Partial discharge (PD) often begins with cracks or gas-filled voids in solid insulation or with gaseous bubbles in liquid insulation. These presences can degrade the quality of insulator. PD detection can identify these cracks at high voltage equipment such as power cables and power transformer at the early stage. One of PD detection methods is acoustic emission (AE) detection. PD produces an ultrasonic signal that can be captured by an AE sensor. The signal captured is then analysed by capturing the time of the receiving signal onto the sensor. The information related to time can be used for allocating the PD for maintenance purpose. This paper shows the influence of the distance between PD source and the AE sensor towards the arrival time of propagation wave in power transformer. In this study, the four placements of sensors were analysed by having three possible PD sources to represent the variety of distances between the PD source and the sensor. The simulated signal is generated by MATLAB and the arrival time is captured using time of arrival (TOA) method. The time captured and the distance between the PD source and arrival time showed that the relationship is proportional to one another.
  • Publication
    Simulation of differential relay for transformer protection
    ( 2020-03-20)
    Azizan N.S.
    ;
    Wooi Chin Leong
    ;
    Baharuddin Ismail
    ;
    Syahrun Nizam Md Arshad @ Hashim
    ;
    Isa M.
    ;
    Wan Azani Wan Mustafa
    ;
    Rohani MNK
    In electric power system, transformers are an important element and their protection are critical. As the transformer might be damaged during a fault, faster and more selective protection was required. For this purpose, the design of differential protection was utilized. In this study, the differential relay simulation has been successfully done using MATLAB/Simulink. The essential approach is to protect the power transformer against internal faults and avoid interference in the power system. The evaluation has been accomplished at different fault conditions. Several types of faults including double line-to-ground, single line-to-ground and line-to-line faults are studied. Simulation studies were performed and the relays performance with different system parameters and conditions were investigated. The obtained results illustrated for the differential relay represents an appropriate action.
  • Publication
    Effect of concrete orientation as an enhancement material in grounding system
    ( 2020-07-09)
    Hasni N.A.S.
    ;
    Syahrun Nizam Md Arshad @ Hashim
    ;
    Amizah Md. Ariffen
    ;
    Halim N.H.
    ;
    Wooi Chin Leong
    ;
    Muhammad Izuan Fahmi Romli
    ;
    Bakar O.A.
    To achieve an excellent grounding system, an alternative solution was developed by using enhancement material to modify the soil surrounding the rod. These materials can effectively reduce soil resistivity and grounding resistance for a better grounding system. To achieve this goal, the fundamental part must be taken into account. In this study, the main objective is to analyze different concrete orientations as enhancement material in the grounding system. A 3-D orientation of concrete has been designed using Finite Element Method (FEM) software to analyze the performance of the electric field in the grounding system with different orientation of concrete. Every orientation of concrete had been clarified into four different cases which are full concrete, half concrete, three-quarter concrete, and a quarter concrete. From the result, full concrete is the best orientation of concrete design to be employed at the grounding site as it has a low electric field compared to the other concrete orientation.
  • Publication
    Simulation of reverse power relay in 11 kV generator protection
    ( 2021-05-03)
    Wooi Chin Leong
    ;
    Lee Y.Y.
    ;
    Nabipour-Afrouzi H.
    ;
    Mousa M.I.
    ;
    Syahrun Nizam Md Arshad @ Hashim
    ;
    Mehranzamir K.
    ;
    Mohamad Nur Khairul Hafizi Rohani
    This paper proposed the modelling and simulation of generator protection for power system using digital reverse power relay. The operations of the power plant are often interrupted by the reverse power generation. Therefore, generators need to be closely monitored and controlled. In this study, 11 kV synchronous generators are connected to 220 kV load through a step-up transformer, and a new model of reverse power relay is added for generator protection. The reverse power relay proposed in this paper is a digital relay with high accuracy and high reacting speed. Several cases based on various types of mechanical inputs to the generator were studied to test the operation of the reverse power relay. This simulation was done using MATLAB/Simulink. The results show that the 11 kV generator protection is successful with this new model reverse power relay. Besides, the simulation results were similar result compared to the theory result. From the simulation results, the integral output of the relay will reach the threshold value 'L' whenever there is a reversed power flow fault found in the system. Consequently, the relay will be triggered to provide protection for the generator. This model has been added into online resources of MATLAB Power System Tools. In addition, this model may also help the engineers to develop the analytical skills under various conditions.
  • Publication
    Grounding performance of hydrogel, silica gel and charcoal ash as additive material in grounding system
    ( 2024-06)
    Wooi Chin Leong
    ;
    Shafirol Nizam Osman
    ;
    Hadi Nabipour Afrouzi
    ;
    Syahrun Nizam Md Arshad @ Hashim
    ;
    Kamyar Mehranzamir
    ;
    Muzaidi Othman @ Marzuki
    Grounding enhancement materials (GEMs) are one of the additive materials which can change the grounding performance without lots of significant costs. The study aimed to assess the performance of laterite and peat soil, copper and galvanized conductors, and determine the effectiveness of additional materials in reducing grounding resistance. Altering soil characteristics can enhance the conductor's contact area, achieving lower grounding resistance without high costs. Hydrogel, silica gel, and charcoal ash were mixed with soil for testing. Grounding resistance values were measured and collected using the Fall-of-Potential Method using Kyoritsu Earth-Tester-Model-4102. The number of GEMs used were 300g and 600g. Hydrogel, silica gel, and charcoal ash added to soil reduced grounding resistance. Among the various Ground Enhancement Materials (GEMs) tested, hydrogel exhibited the most impressive performance, boasting the lowest grounding resistance at just 56% compared to the reference grounding system. Silica gel followed closely as the second-best performer, with an average grounding resistance of 77% relative to the reference system and lastly is charcoal ash with an average grounding resistance of 77% relative to the reference system. These GEMs significantly enhanced soil conductivity. Furthermore, when considering different soil types and conductor materials, it was observed that peat soil combined with galvanized conductors achieved notably lower grounding resistance in comparison to laterite soil and copper conductors, respectively.
  • Publication
    Lightning Strikes Mitigation Plan on Transmission Line Tower at Kedah Paddy Field
    ( 2021-06-11)
    Othman N.A.
    ;
    Halim H.A.
    ;
    Wooi Chin Leong
    ;
    Melaty Amirruddin
    ;
    Nurhakimah Mohd Mukhtar
    This paper presents a mitigation plan for lightning strikes towards the transmission line tower at Kedah paddy field area. The ATP Draw software produces a schematic diagram of an incoming main intake sub-station and a transmission tower struck by lightning. Simulation on multiple soil resistance values and multiple soil conditions are then plot into graphs. A static eliminator reduces the electrostatic force between negatively charged thunder clouds with a positively charged steel transmission tower. It shows that a static eliminator makes the transmission line act invisibly in the lightning pathway. This protection level avoids surge current from transmitting in the transmission line reduces the possibility to damage surge arrestor.
  • Publication
    A Review: Partial Discharge Detection using UHF sensor on High Voltage Equipment
    ( 2020-01-07)
    Roslizan N.D.
    ;
    Mohamad Nur Khairul Hafizi Rohani
    ;
    Wooi Chin Leong
    ;
    Isa M.
    ;
    Baharuddin Ismail
    ;
    Afifah Shuhada Rosmi
    ;
    Wan Azani Wan Mustafa
    Partial discharge (PD) is one of the most popular failure or breakdown that can happen at high voltage (HV) equipment. PD is the fault that causes the insulation breakdown occurred between two electrodes. It happened or occurred because of the improper insulation, ageing, environment effect and manufacturing defects. The loss of the power will affect consumer and system operation. One of the technique that can measure or detect the PD is by using ultra high frequency (UHF) method for HV equipment insulation condition monitoring and assessment. In this paper, the application of UHF method have been reviewed as the best method to detect PD in transformer, GIS and cable. The UHF method for every electrical equipment is described in order to detect the PD and the laboratory result shows that this method can be considered as suitable technique. Based on this review, the new design in UHF sensor is required in order to improve the sensitivity and bandwidth for PD detection in HV equipment. The valuable parameter such as size and PD frequency range can be used for early stage of designing new the UHF sensor.
  • Publication
    High voltage Testing characteristics of kenaf as grounding enhancement material
    ( 2022-01-01)
    Bakar O.A.
    ;
    Syahrun Nizam Md Arshad @ Hashim
    ;
    Othman M.B.
    ;
    Wooi Chin Leong
    ;
    Adzis Z.
    Lightning protection elements consist of a grounding system. The grounding system's main task is to disburse the current into the earth safely. This research aims to lower the resistance, thus creating a good path for the grounding system using natural enhancement material as backfill material. Since the kenaf core is brittle, not dense and loose, therefore clay as a bonding agent is mixed as a backfill material. Various mixtures of clay and kenaf are filled in the acrylic box. The sample goes through the high voltage AC and DC levels until the sample breakdown reaches. The upper limit of voltage depends on the material and its condition, either dry or wet. The data records the temperature and relative humidity of the laboratory before running the testing. After every increment, high voltage AC will be applied constantly for ten seconds at the backfill material. The testing also observes any physical changes in the material. From HVAC and HVDC tests, kenaf shows high conductivity. The breakdown voltage considers higher when the percentage of kenaf mix is low. The results show that kenaf has high conductivity and is suitable for use as a natural enhancement material for grounding purposes.