Options
Baharuddin Ismail
Preferred name
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
Now showing
1 - 10 of 20
-
PublicationInfluence 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. ; ; ; ;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. -
PublicationComparative Study of Multiphase 5-Level Cascaded H-Bridge Multilevel Inverter System( 2022-01-01)
;Zawawi M.N.M. ; ; ;Talib M.H.N.In terms of cost and structural design, the cascaded H-bridge multilevel inverter (CHBMLI) has a significant advantage over diode clamped and capacitor clamped multilevel inverters. The total harmonic distortion (THD) of a 5-level CHBMLI system for three different phases (single-phase, three-phase, and six-phase system) is studied and compared in this work. As switching angles play a role in lowering THD, the switching angles for a 5-level CHBMLI are evaluated using four specific switching angle methods in the initial section of this paper. In the simulation of single-phase system, these angles are being utilized. The angles with the lowest THD value are chosen for three-phase and six-phase system simulation. Based on the findings, the higher phase of 5-level CHBMLI is more efficient in decreasing harmonics. -
PublicationA review: Partial discharge detection using acoustic sensor on high voltage transformer( 2020-01-07)
;Akashah N.A. ; ; ; ; ;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 -
PublicationComparative investigations on different types of inductors in single-phase inverterThis article organized in two sections where it compares the performance of single-phase inverters using various types of inductors with differences modulation technique of pulse width modulation (PWM). Not all inductors perform the same function, even the inductance value is the same. The study will investigate the capability of each inductor on its performance to convert the unfiltered AC voltage into filtered sinusoidal AC voltage. The drum core and toroidal core inductors were used in this investigation. For both inductors, the performance will be analyzed based on Bipolar and Unipolar switching schemes in a single unit H-bridge circuit. The validation of results are through experimental assessment only and it will be evaluating the shape of sinusoidal AC voltage and the content of total harmonics distortion in the AC voltage for both inductors.
2 2 -
PublicationHarmonic Analysis of Modified Nine-level Inverter with SHEPWM using Grey Wolf Optimization( 2021-01-01)
; ; ; ; ;Abo sinnee A.S.This paper presents the nine-level multilevel inverter with reduces switch technique using Grey Wolf Optimization (GWO) methods on eliminating the low order harmonics. Using the appropriate switching angles, the low order harmonics can be eliminated completely from the output voltage and current waveform. The switching angles were calculated using the non-linear equations derived from the Fourier series of the output voltage and current waveform. In this paper, GWO algorithm was developed to solve the nonlinear equation and generate the appropriate switching angles specifically for the proposed reduced switch technique topology. The circuit were simulated using PSIM and evaluate based on experimental assessments. The targeted low order harmonic to be eliminated are the 5th, 7th and 11th and two modulation indices will be compared and observed it performance in term of value of total harmonic distortion. The THD results for modulation indexes of 0.7 and 0.82 will be displayed. For modulation index 0.7, simulation yields 7.52% and experimental yields 6.23%. The simulation result for modulation index 0.82 is 5.82% and the experimental result is 4.69%.1 -
PublicationReview Study of Image De-Noising on Digital Image Processing and Applications( 2023-03-01)
;Abdulah C.S.K. ; ; ; ; ; ; ;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 -
PublicationElectrical Tree Image Segmentation Using Hybrid Multi Scale Line Tracking Algorithm( 2023-01-01)
; ; ; ;Jamil M.K. ; ; ; ; ;Mas’ud A.A.Electrical trees are an aging mechanism most associated with partial discharge (PD) activities in crosslinked polyethylene (XLPE) insulation of high-voltage (HV) cables. Characterization of electrical tree structures gained considerable attention from researchers since a deep understanding of the tree morphology is required to develop new insulation material. Two-dimensional (2D) optical microscopy is primarily used to examine tree structures and propagation shapes with image segmentation methods. However, since electrical trees can emerge in different shapes such as bush-type or branch-type, treeing images are complicated to segment due to manifestation of convoluted tree branches, leading to a high misclassification rate during segmentation. Therefore, this study proposed a new method for segmenting 2D electrical tree images based on the multi-scale line tracking algorithm (MSLTA) by integrating batch processing method. The proposed method, h-MSLTA aims to provide accurate segmentation of electrical tree images obtained over a period of tree propagation observation under optical microscopy. The initial phase involves XLPE sample preparation and treeing image acquisition under real-time microscopy observation. The treeing images are then sampled and binarized in pre-processing. In the next phase, segmentation of tree structures is performed using the h-MSLTA by utilizing batch processing in multiple instances of treeing duration. Finally, the comparative investigation has been conducted using standard performance assessment metrics, including accuracy, sensitivity, specificity, Dice coefficient and Matthew’s correlation coefficient (MCC). Based on segmentation performance evaluation against several established segmentation methods, h-MSLTA achieved better results of 95.43% accuracy, 97.28% specificity, 69.43% sensitivity rate with 23.38% and 24.16% average improvement in Dice coefficient and MCC score respectively over the original algorithm. In addition, h-MSLTA produced accurate measurement results of global tree parameters of length and width in comparison with the ground truth image. These results indicated that the proposed method had a solid performance in terms of segmenting electrical tree branches in 2D treeing images compared to other established techniques.1 29 -
PublicationThe effect of amplitude modulation index on harmonic distortion in unipolar SHEPWM inverter( 2021-12-01)
; ; ; ; ;The appearance of low order odd harmonic in the AC power line can be mitigated by projecting a proper switching angle during the conversion of the inverter. The switching angles can be obtained by solving the numerical nonlinear equation using numerous solving techniques and algorithms. Several studies shows the value of harmonic significantly increase whenever the amplitude modulation decrease for the SPWM switching scheme of the inverter. However, this topic has not yet covered in the single-phase SHEPWM inverter. This paper is to study the effect of the amplitude modulation index towards the harmonic distortion in the SHEPWM switching technique. To solve the numerical equations, MATLAB code is used to produce the specific switching angles to drive the inverter by solving the numerical equations. The validation of results thru hardware implementation using EZDSPTMS320F28335 to produce the digital signal for controlling the inverter. The targeted low order harmonic to be eliminated are the 3rd, 5th and 7th and three four amplitude modulation indices will be compared and observed in term of total harmonic distortion. The THD results for amplitude modulations 0.6, 0.7, 0.8 and 0.9 are 17.50%, 15.10%, 13.30% and 10.63%.21 33 -
PublicationHilbert fractal UHF sensor based on partial discharge detection signal for on-line condition monitoring in power transformer( 2020-01-01)
;Roslizan N.D. ; ; ; ; ;Akashah N.A.Mukhtaruddin A.PD detection is an effective method of inspecting insulation defects and identifying potential faults in a power transformer. Electromagnetic waves generated due to PD can be detected by ultrahigh-frequency (UHF) sensor in the frequency band greater than 300 MHz. However, the size and the frequency bandwidth of a UHF sensor for PD detection are the concern for practical installation inside a transformer. High sensitivity and wide bandwidth of sensors are needed in order to detect the PD signal in an early stage. This paper presents an array 4th order Hilbert fractal UHF sensor for PD detection inside a power transformer. This UHF sensor was modeled to capture PD signal in a range of frequencies between 300 MHz to 3 GHz. The sensor is designed by using CST software where the transmission lines combined 2 sensors become 1 output by setting the dimension of 100 x 200 mm for length and width with FR4 epoxy substrate of thickness 1.6 mm. Based on the simulation result, the proposed sensor is obtained a PD signal measurement with a reflection coefficient below-10 dB with VSWR ≤5. The advantages of this sensor have a wide bandwidth, high sensitivity and suitable size for easy installation. Thus, this sensor has been qualified as UHF PD detection in the power transformer.10 30 -
PublicationComparison of Image Restoration using Median, Wiener, and Gaussian Filtering Techniques based on Electrical Tree( 2021-01-01)
;Abdulah C.S.K. ; ; ;Isa M.A.M. ;Electrical treeing lead to a major cause of a breakdown in solid insulation. Thus reduced solid insulation performance by degrading the insulation. Hence, it is important to study the electrical treeing and learn the root cause of the treeing formation. In this paper, the performances of median, wiener, and gaussian filters in restoring noisy images are studied based on electrical tree images. The electrical tree colour images is being transform into grayscale images, noisy images using impulse noise (salt and pepper), and finally motion blur are applied. Even though, there are several number of filters available, this paper focus on median, wiener, gaussian, and combination of the filters. In the end, comparison between these filters is made to study the efficiency using PSNR, SNR, and MSE in graph form.1 39