Muzamir Isa
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Preferred name
Muzamir Isa
Official Name
Muzamir, Isa
Alternative Name
Isa, M.
Isa, Muzamir Bin
Isa, Muzamir
Isa, Muzamir A.M.
Bin Isa, Muzamir
Main Affiliation
Scopus Author ID
16642710600
Researcher ID
G-4076-2017

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  • 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
    Diagnostics of oil filled cable terminations
    ( 2006)
    Mohd Rafi Adzman
    ;
    Muzamir Isa
    ;
    Baharuddin Ismail
    ;
    Matti Lehtonen
    ;
    Petri Hyvonen
    Cable termination is one of the important components in the electrical power system. A failure of it can cause a long interruption, costly repair and loss of revenue. An existing oil filled cable termination such as rubber tube and porcelain type of cable termination require an observation and preventive maintenance in order to prevent an enormous electrical system failure in future. One of the defects ot this type of oil filled cable termination is lack of insulation oil inside it. The worst case if it becomes totally empty and at the same time there is no approach taht can help detect it. This paper presents the work carried out to find any possible method that can be used to detect a drying out of oil impregnated paper tape cable terminations. Futhermore, the diagnosis has to be used without destroying the terminations. Two diagnosis methods, infrared (IR) thermography and X-ray imaging are reviewed and the diagnosis result is presented. By comparison of two diagnosis method in this work, the X-ray imaging method is the best approach to observe and detect a drying out of paper tape oil impregnated cable terminations.
      1  179
  • 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
    Review of feasibility wind turbine technologies for highways energy harvesting
    (IOP Publishing, 2020)
    Liew Hui Fang
    ;
    Baharuddin Ismail
    ;
    Abd Rahim, Rozemizi
    ;
    Muzamir Isa
    ;
    Hassan, Syed Idris Syed
    Wind energy is one of the non-conventional forms of energy and it is available in affluence. It is also claimed that the wind power is pollution-free, replacement of fossil fuel and that its source of energy is freely available. Electricity can be generated with the help of a wind turbine generator. In this paper, a comprehensive study on contemporary portable wind energy harvesters has been conducted. The different existing performance such as reliability evaluation models, various problems related to structure wind turbine components (blade, gearbox, generator and transformer) and grid for wind energy system have been discussed. At the same time, experimental analysis is focused on behaviour, especially characteristics of impact wind energy, performance as lots of advanced research work has already been done or going on the harnessing of natural wind energy. In this review paper, a different model wind turbine has been studied from previous testing purpose presented. This review aim of utilizing this wind energy in a most effective manner to get the maximum electric output, and therefore the government can think over implementing the suitable type of wind turbine configuration selected highway at low cost as our installation site taking the advantage of the moving vehicles on both sides of the road.
      12  1
  • Publication
    Electrical Tree Image Segmentation Using Hybrid Multi Scale Line Tracking Algorithm
    ( 2023-01-01)
    Mohd Annuar Mohd Isa
    ;
    Mohamad Nur Khairul Hafizi Rohani
    ;
    Baharuddin Ismail
    ;
    Jamil M.K.
    ;
    Muzamir Isa
    ;
    Afifah Shuhada Rosmi
    ;
    Mohd Aminudin Jamlos
    ;
    Wan Azani Wan Mustafa
    ;
    Nurulbariah Idris
    ;
    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
  • Publication
    Hilbert fractal UHF sensor based on partial discharge detection signal for on-line condition monitoring in power transformer
    ( 2020-01-01)
    Roslizan N.D.
    ;
    Mohamad Nur Khairul Hafizi Rohani
    ;
    Afifah Shuhada Rosmi
    ;
    Baharuddin Ismail
    ;
    Muzamir Isa
    ;
    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
  • Publication
    Merekabentuk pengesan discas permukaan di dalam ''Inclined-Plane Test" dengan menggunakan kaedah optik
    ( 2007)
    Muzamir Isa
    ;
    Baharuddin Ismail
    ;
    Ismail Daut
    ;
    Che Mat Hadzer
    ;
    Faizah Abu Bakar
    ;
    Mohd Rafi Adzman
    Laporan ini bertujuan untuk memberikan seberapa maklumat tentang ciri-ciri aktiviti discas permukaan secara khustmrya dan aktiviti discas sejara secara umumnya serta peringkat-peringkat proses merekabentuk alat pengesan terhadap aktiviti ini menggunakan kaedah optikal ia meliputi kaji selidik dalam teori-teori tentang kejadian discas permukaan, kriteria-kriterianya dan proses bagaimana ia boleh dikesan oleh sesuatu alat pengesan. Objektif utama projek ini dijalankan adalah untuk merekacipta satu alat pengesan yang menggunakan kaedah optik bagi mengesan dan mengenalpasti kejadian aktiviti discas permukaan pada peralatan elektrik terutamanya pada peralatan voltan tinggi. Adalah diharapkan agar alat pengesan yang dihasil daripada projek ini akan dapat digunakan bagi kegunaan untuk mengesan dan seterusnya mengenalpasti lokasi dimana telah berlakunya aktiviti discas permukaan.
      13  42
  • Publication
    Selective harmonic elimination pulse width modulation for five-phase cascaded multilevel inverter using non-notch and notch switching technique
    ( 2020-01-01)
    Walter M.S.M.A.
    ;
    Baharuddin Ismail
    ;
    Muhammad Zaid Aihsan
    ;
    Siti Khodijah Mazalan
    ;
    Bimazlim M.A.S.
    ;
    Muzamir Isa
    ;
    Mohamad Nur Khairul Hafizi Rohani
    ;
    Sengodan T.
    As in this era, the conversion of DC power to AC power is a necessity in the power system in order to make useful of renewable energy. The most commonly used switching mechanism is known as inverter or multilevel inverter. However, this switching may cause harmonics. Harmonics usually occur in a power system due to distortion, which can cause a lot of unwanted problems. It could appear either in voltage or in current waveforms. Minimization of Total Harmonic Distortion (THD) is necessary in order to maintain a good power system. This paper introduces selective harmonic elimination pulse width modulation for five-phase cascaded multilevel inverter. The proposed switching technique for five-phase cascaded multilevel inverter used in this research is non-notch and notch switching technique. Particle Swarm Optimization (PSO) algorithm was used as an optimization technique to find switching angles for non-notch and notch switching techniques. In addition, the simulation of a seven-level five-phase cascaded multilevel inverter for both switching operations is carried out in the PSIM environment. The results show that the non-notch switching was able to eliminate lower order harmonics up to the 7th harmonic. In addition, the notch switching technique managed to eliminate lower order harmonics up to the 21st harmonic for 3/3/3 switching distribution.
      4  40
  • Publication
    Analysis of acoustic sensor placement for PD location in power transformer
    (Scientific and Technological Research Council of Türkiye (TÜBİTAK), 2020)
    Khairul Nadiah Khalid
    ;
    Rohani, Muhammad Nur Khairul Hafizi
    ;
    Chai Chang YII
    ;
    Baharuddin Ismail
    ;
    Muzamir Isa
    ;
    Wan Nurul Auni Wan Muhammad
    Partial discharge (PD) is an abnormal activity that occurs in high-voltage components, such as power cables, switchgear, machines, and power transformers. Such activity needs to be diagnosed for the equipment to last longer as PD could harm the insulation and potentially lead to asset destruction from time to time. Moving one or more externally mounted acoustic sensors to different locations on the transformer tank is commonly used in order to detect and locate PD signal occurring in the power transformer. However, this procedure may lead to less accuracy in PD identification. Therefore, this research paper presents an analysis of acoustic sensor placement based on time of arrival (TOA) technique for PD location in a power transformer. The detection and location can be determined by permanently installing the acoustic sensor to provide valuable data in an early stage of occurrence for online condition PD monitoring. Several methods are available for the detection of PD signal, whereby one of the best choices is via acoustic emission (AE). PD creates an ultrasonic signal used for PD detection. This paper proposes the possible placement of AE sensors to be mounted on the power transformer wall based on ideal and static PD signals. The sensors were placed in order to capture the PD signal without any disturbance signal from inside or outside the tank. The time for the signal for the first approach for each sensor is recorded to estimate the PD location using the TOA technique. A comparison between the least square method (LSM) and Gauss-Jordan elimination (GJE) for the TOA technique was analyzed to differentiate the resulting performance. This research utilized three different PD sources to apply the performance analysis on PD locations, while five cases were proposed to represent the five different placements of four sensors for the analysis. This research ultimately suggests that sensors be placed and randomly mounted on the four sides of the transformer tank, with one sensor allocated to one side. Among all five cases, Case 1 and Case 5 yielded a displacement error (DE) less than others, while between these two cases, Case 5 gave the lowest DE. The findings were recorded based on LSM and GJE methods used to differentiate the resulting performance.
      1  6