Baharuddin Ismail
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Baharuddin Ismail
Official Name
Baharuddin, Ismail
Alternative Name
Ismail, Baharuddin Bin
Ismail, Baharudidn
Ismailf, B.
Main Affiliation
Scopus Author ID
24447820000
Researcher ID
GEW-9377-2022

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  • Publication
    Influence of Electrical Tree Characterization Change Based on Tree Inception Voltage in HV Solid Insulation
    ( 2023-01-01)
    Abdulah C.S.K.
    ;
    Rosmi A.S.
    ;
    Isa M.A.M.
    ;
    Baharuddin Ismail
    ;
    Mohamad Nur Khairul Hafizi Rohani
    ;
    Wan Azani Wan Mustafa
    ;
    Kamarol M.
    ;
    Yii C.C.
    ;
    Al-Attabi K.
    ;
    Almoussawi Z.A.
    To improve accuracy of degradation diagnosis for HV solid insulation, it is important to clarify the mechanism of inception and characterization of electrical-tree. In this paper, the study of influence between TIV and electrical tree characterization was done in a laboratory experiment by monitoring the TIV values and electrical tree propagation. This experiment involve using charged couple device camera (CCD) to capture and record the electrical tree thorough the experiment, a microscope to enlarge the needle tip that was inserted into the XLPE sample, and finally a personal computer to display the whole treeing growth process. Then, the voltage was injected into sample of XPLE constantly until the electrical tree start to initiate at the needle tip. As a result, the electrical tree take form based on the TIV, small number of TIV produce a less dense electrical tree compare to higher value of TIV. Additionally, denser electrical tree propagates faster and may lead to early breakdown.
  • Publication
    Comparative study of optimization algorithms for SHEPWM five-phase multilevel inverter
    (Institute of Electrical and Electronics Engineers (IEEE), 2020)
    Muhammad Aniq Shahmi Bin Bimazlim
    ;
    Baharuddin Ismail
    ;
    Muhammad Zaid Aihsan
    ;
    Siti Khodijah Mazalan
    ;
    Muhammad Sirajuddin Muhammad Azhar Walter
    ;
    Mohamad Nur Khairul Hafizi Rohani
    Conversion of DC to AC is widely used as an essential need for the power system to harness renewable power source in this era. Multilevel inverter is a mechanism which capable of harnessing these renewable energies. Unfortunately, harmonics occur in the system due to distortions and causing much unwanted problems at the power output. Therefore, the elimination of harmonics and reduce Total Harmonics Distortion (THD) are needed to maintain good power output. Application of Selective Harmonics Elimination Pulse Width Modulation (SHEPWM) can be used in the multilevel inverter to solve the problem. In this paper, optimization algorithms such as Particle Swarm Optimization (PSO), Whale Optimization Algorithm (WOA) and Sine Cosine Algorithm (SCA) were applied for finding suitable switching angle for SHEPWM. The calculated switching angle was applied into seven-level five-phase multilevel inverter for various modulation indexes. In addition, the simulation of the multilevel inverter also done using PSIM software. The results show that the selective lower order harmonics, 3rd and 7th are completely eliminated for all three algorithms. In addition, the time taken for newly discovered algorithms to find switching angles for seven-level five-phase inverter is faster compared to PSO.
  • Publication
    Performance evaluation of Edge-based segmentation methods for electrical tree image analysis in high-voltage experiments
    (Semarak Ilmu Publishing, 2025-06)
    Mohd Annuar Mohd Isa
    ;
    Mohamad Nur Khairul Hafizi Rohani
    ;
    Afifah Shuhada Rosmi
    ;
    Baharuddin Ismail
    ;
    Mohamad Firdaus Azahari
    ;
    Mohamad Kamarol Jamil
    ;
    Noor Syazwani Mansor
    ;
    Abdullahi A. Mas’ud
    ;
    Firdaus Muhammad-Sukki
    This research evaluates the performance of edge-based segmentation methods in analysing two-dimensional (2D) electrical tree images obtained during high-voltage (HV) electrical tree experiments. Non-uniform illumination in 2D optical images poses challenges in accurately extracting and measuring the original treeing image. Edge segmentation emerges as a promising solution to precisely distinguish tree structures from the insulation background within the image. Cross-linked polyethylene (XLPE) samples were subjected to HV stress for real-time propagation observation, followed by extraction and segmentation of treeing images using edge-based operators. The findings emphasize the superiority of the Roberts edge operator in accurately detecting electrical trees, showcasing the highest average accuracy of 97.01% and 99.58% specificity, while also demonstrating relatively high sensitivity. Moreover, the Roberts method provide much precisely measures the propagation length and width than conventional measurement method, closely approximating the actual tree measurements. This research emphasizes the significance of accurate segmentation for investigating electrical tree propagation in XLPE materials and provides recommendations for future research, especially in HV XLPE cable manufacturing.
  • Publication
    Analysis of array UHF sensor for partial discharge detection in power transformer
    (Semarak Ilmu Publishing, 2025-08)
    Nur Dayini Roslizan
    ;
    Mohamad Nur Khairul Hafizi Rohani
    ;
    Afifah Shuhada Rosmi
    ;
    Baharuddin Ismail
    ;
    Mohd Aminudin Jamlos
    ;
    Raimi Dewan
    Partial discharges (PD) are small electrical discharges that occur within insulation materials and can lead to equipment failure and safety hazards. The Ultra High Frequency (UHF) sensor consists of a broadband antenna and a UHF receiver, which are designed to detect and analyse the electromagnetic emissions from partial discharges. This paper presents the design and characterization of the 4th order Hilbert fractal UHF sensor for PD detection in power transformer. The sensor is designed to operate in the frequency range of 300 MHz to 3 GHz and is optimized for high gain and directivity. The performance of the sensor is evaluated using simulation and measurement techniques. Simulation results show that the sensor has directivity of 7.9 dBi and reflection coefficient below -10 dB with VSWR ≤ 5.
  • Publication
    Performance analysis of a modified reduce component count multilevel inverter
    ( 2020-01-07)
    Siti Khodijah Mazalan
    ;
    Baharuddin Ismail
    ;
    Muzamir Isa
    ;
    Muhammad Syahril Bahari
    ;
    Mohamad Nur Khairul Hafizi Rohani
    Reducing component in circuitry is desirable in many innovations. In multilevel inverter (MLI) perspective, the increasing of switching devices for a higher-level output will significantly increase power losses, thus affected the output harmonic distortion. In this paper, an extended and simplified three-phase reduce component count multilevel inverter (RCCMLI) structure adapted from S. S. Lee, Cascaded Compact-Module Multilevel Inverter (CCM-MLI) is demonstrated and analysed. Symmetrical reduce component structure with H-bridge inverter is considered in this work. For simplification purpose, the current path conduction for reverse current is not demonstrated in this paper. A simulation-based result is presented to observe the performance of RCCMLI with regards to its output voltage harmonic content. Related predetermined parameter values are included in this report. Particularly, this paper verified the aforementioned RCCMLI, but in higher level and three-phase application, which will further improve the pseudo-sinusoidal inverter output as it eliminates the triplens harmonic component compare to single-phase environment. As for the lower order odd harmonics elimination, computational algorithm namely Particle Swarm Optimization (PSO) has been implemented in the RCCMLI control strategy. In comparison to the traditional Cascaded H bridge (CHB), this work finds that employing the switching angle optimization in the proposed RCCMLI produce comparable improvement in minimizing the output voltage harmonic and able to bring the output quality closer to comply with IEEE 519 distortion limit with fewer components and compact size inverter.
      30  1
  • Publication
    A review: Partial discharge detection using acoustic sensor on high voltage transformer
    ( 2020-01-07)
    Akashah N.A.
    ;
    Mohamad Nur Khairul Hafizi Rohani
    ;
    Afifah Shuhada Rosmi
    ;
    Muzamir Isa
    ;
    Norfadilah Rosle
    ;
    Baharuddin Ismail
    ;
    Wooi Chin Leong
    Partial discharge (PD) is an electrical discharge which is one of the most critical breakdown factor that is affecting the electrical equipment. The loss of the power will affect consumers and system operation. High voltage (HV) transformer is one of the equipment's subjected to phenomena PD. In this paper reviews an application of acoustic methods in transformer and piezoelectric sensors application on PD detection in HV transformer. Based on this review, the new design in acoustic sensor is required in order to improve the sensitivity and bandwidth for PD detection at HV transformer. The valuable parameter such as materials, size, and PD frequency range were discussed in this paper and can be used for early stage on designing new acoustic sensor. This detection method given some benefits on preventing the power electrical system from breakdown.
      1  28
  • Publication
    Image de-noising based on WMF technique for electrical trees structure in high voltage cable insulation
    (Semarak Ilmu Publishing, 2025-11)
    Siti Khadijah Za'aba
    ;
    Mohamad Nur Khairul Hafizi Rohani
    ;
    Baharuddin Ismail
    ;
    Afifah Shuhada Rosmi
    Electrical treeing is a common problem during the pre-breakdown phenomenon in solid insulations due to the damage caused by Partial Discharge (PD) that progresses through stressed insulation via chemical degradation, which resembles the shape of a tree root. This resulted in a decrease in performance through degrading the insulation, which became a serious problem while dealing with electrical equipment. Hence, a deep understanding of electrical tree structure is vital to improving the quality of solid insulations. Ergo, optical microscopy is primarily used to examine tree structures, shapes, and fractal dimensions to reconstruct electrical tree structures for morphological study. However, optical microscopy images are frequently degraded by noise from readout procedures or image data acquisition systems, noise caused by occlusion, illumination, non-uniform intensity, destroying potential tree pixels, and a critical loss of information about the electrical tree structures. Therefore, this research proposed the Wiener Median Fusion (WMF) filter for electrical tree study. The performance of the WMF de-noising technique improves the image quality for the precise portrayal of the electrical tree structure based on thresholding segmentation algorithm analysis in terms of accuracy, sensitivity, and false positive rate. Based on the analysis of the thresholding segmentation algorithm, Otsu's thresholding exhibits the highest result compared to Niblack. The Otsu's overall percentage in terms of accuracy is 80.2934%, the sensitivity is 99.1513%, and the false positive rate is 82.6265%.
      1  2
  • Publication
    Review of Edge-based Image Segmentation on Electrical Tree Classification in Cross-linked Polyethylene (XLPE) Insulation
    ( 2021-06-11)
    Mohd Annuar Mohd Isa
    ;
    Mohamad Nur Khairul Hafizi Rohani
    ;
    Baharuddin Ismail
    ;
    Afifah Shuhada Rosmi
    ;
    Isa M.
    ;
    Wan Azani Wan Mustafa
    ;
    Kamarol M.
    ;
    Mansor N.S.
    ;
    Nazar N.S.M.
    Electrical trees are the degradation events most linked with partial discharge (PD) activity in cross-linked polyethylene (XLPE) insulation of high voltage (HV) cables. To investigate tree structures and forms, study of electrical tree structures for morphological analysis often carried out using optical microscopy. However, since the noise induced by the occlusion and illumination, as well as by non-uniform intensity either from optical device's setting or the non-standard readout procedure, causes the deterioration of the original microscopy images, resulting in critically loses of information pertaining the tree structures making it difficult to obtained accurate measurement. Image segmentation is one of the potential solutions as it is well-suited for extracting information or certain features from microscopy images. This paper provides review of several segmentation techniques applied on the classification of electrical tree image acquired through lab environment. The works can be separated into three stages. The first step includes the preparation of samples and collection of treeing images by means of real-time microscopy observations. The captured data would then be pre-processed to achieve image binarization. In the next step, image segmentation process is conducted using existing edge-based segmentation methods including Prewitt, Roberts, Canny and Kirsch's templates. Later, comparative analysis will be performed using IQA (image quality assessment) metrics of accuracy, sensitivity, specificity, false-positive-rate and the Matthews Correlation Coefficient (MCC) as the final step. Performance-wise indicates that Kirsch's template able to segment most of the treeing pixels with accuracy of 97.63%, 63% sensitivity, 98.18% specificity and 0.46 MCC while showing low pixels misclassification. This result provides better justification for the integration of the edge-based technique in developing image segmentation algorithm well-matched for the electrical tree analysis in the future.
      36  1
  • Publication
    Electrical tree image de-noising using threshold wavelet transform and wiener filter
    (Semarak Ilmu Publishing, 2025)
    Mohamad Nur Khairul Hafizi Rohani
    ;
    Cik Siti Khadijah Abdulah
    ;
    Nur Dini Athirah Gazata
    ;
    Mohd Anuar Mohd Isa
    ;
    Baharuddin Ismail
    ;
    Mohamad Kamarol Jamil
    ;
    Afifah Shuhada Rosmi
    ;
    Firdaus Muhammad-Sukki
    ;
    Abdullahi A. Mas’ud
    ;
    Noor Syazwani Mansor
    Electrical treeing occurred in solid dielectric materials, especially in electrical application with high voltage. The occurrence of electrical tree happens when high electric fields applied, causing tiny channels or paths to form. The main issue during the data collection process is the changes of lighting, making it difficult to study the tree's propagation length, fractal dimension, and growth rate due to corrupted images. This research aims to analyse electrical tree structure images in XLPE material using a CCD camera and develop image de-noising techniques to suppress noise on the electrical tree image. The performance was then analysed using the Otsu thresholding algorithm for accurate segmentation. The methodology was divided into four phases: sample preparation, experimental setup, image pre-processing in MATLAB, and testing four de-noising filters: Wiener, median, NLM, and Gaussian. The Wiener filter with higher PSNR, SNR, and RMSE was selected and using superimposed method, both threshold wavelet transforms and wiener was combined to eliminate the noise. Finally, the proposed method of superimposed was tested with the Otsu thresholding method to evaluate accuracy, sensitivity, and specificity of the combination filter. Based on the analysis of PSNR, SNR, and RMSE, the performance of the threshold wavelet and Wiener filter (TWWF) de-noising technique improves the image quality of the electrical tree structure. Thus, for the Otsu thresholding segmentation algorithm analysis, it also had the highest values in terms of accuracy, sensitivity, and specificity.
      1  1
  • Publication
    Review Study of Image De-Noising on Digital Image Processing and Applications
    ( 2023-03-01)
    Abdulah C.S.K.
    ;
    Mohamad Nur Khairul Hafizi Rohani
    ;
    Baharuddin Ismail
    ;
    Mohd Annuar Mohd Isa
    ;
    Afifah Shuhada Rosmi
    ;
    Wan Azani Wan Mustafa
    ;
    Ahmad Zaidi Abdullah
    ;
    Wan Nor Munirah Ariffin
    ;
    Jamil M.K.M.
    This paper reviews several studies of image de-noising on digital image processing and applications. Noisy images contain different noise that exist either due to environment or electronic interferences. Ergo, de-noising is crucial to eliminate the noise that disturb data collecting process. The impact of de-noising on image processing can result for accurate and precise data collected from the image. Additionally, de-noising process required several crucial steps that help to enhance knowledge on digital image and its application. Hence, study and understanding de-noising can improve multiple aspect such as image quality, data sensitivity and specificity, accuracy of the collected data, and increase the percentage of each parameter.
      1