Ahmad Muhyiddin Yusof
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Preferred name
Ahmad Muhyiddin Yusof
Official Name
Ahmad Muhyiddin, Yusof
Alternative Name
Yusof, Ahmad Muhyiddin
Yusof, Ahmad Muhyiddin Bin
Main Affiliation
Scopus Author ID
58332127000

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Design of load control system using DTMF

2020 , Mohd. Mustafa Al Bakri Abdullah , Mohd Zamri Hasan , Ahmad Muhyiddin Yusof , Ahmad Shukri Fazil Rahman

In agricultural sectors, one of the problems faced by the farmer is the water usage for watering schedule sometimes was wasted. With inefficient irrigation system, the water wastage could occur and resulting the excessive moisture for the soil and damaging the crops. The load control system in agricultural sectors especially for irrigation system is very important since it can affect the efficiency and the productivity of the operationsThe agricultural sectors also have many latest technologies implemented to the system such as irrigation system, temperature and humidity detection system and many other systems in order to operate efficiently so it can give profitable outcome. So, a desired load control system using Dual-Tone Multiple Frequency (DTMF) will be design for irrigation system in order to overcome the inefficiency of manual irrigation system. By using DTMF to control the irrigation system, it will consume less time and it can be control in a wide range. Firstly, by using Arduino IDE software, the coding for this control system is written with C++ language. Then, it will be compiled to make sure the coding working without any errors before it is uploaded into the Arduino Uno board. The coding will then be uploaded by connecting the Arduino Uno board to the computer via USB. Next, the schematic layout design of this control system will be simulated using Proteus 8 and Fritzing software. After the simulation of the circuit is successful, the construction of the hardware will take place. The hardware of this load control system that be assembled first is connecting the cell phone to the DTMF decoder by using 3.5mm jack. Then, from the DTMF decoder it will be connected to the Arduino Uno board. The 4 channel 12V relay then connected to the output port of the Arduino Uno. In conclusion, this irrigation control system works when the user sent the signal using cell phone and it will be received by the other cell phone that attach to the DTMF decoder

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Lightning generated electric field over land and sea at northern region of peninsular malaysia: Measuring setup

2020-09-01 , Ahmad Muhyiddin Yusof , Abdul-Malek Z. , Wooi Chin Leong

Lightning electric fields can be characterized based on its origins which include the preliminary breakdown, stepped leader, return stroke, subsequent return stroke, dart leader, dart-stepped leader, narrow bipolar pulses, cloud activity between strokes, regular pulse trains, K and M changes, and chaotic pulse trains. The aim of this work is to describe a lightning measuring setup suitable for characterizing lightning electric fields and their propagation when the measuring sensors are close to the sea. A location close to the sea in Northern Malaysia was identified and prepared for the study. Parallel plate and vertical whip antennas are used as the main sensors, which are connected to a high-speed digital storage oscilloscope through customized analog filter buffer circuits. Noise-distortion effects in the recorded data are filtered using MATLAB computer simulation before further analyses are carried out. The 1-D wavelet technique is used in the signal denoising process. Preliminary results show that the installed setup and denoising method is adequate and potentially efficient for the pre-processing of lightning electric field signals, and hence can be used for the detailed characterization study including the effects of sea on lightning characteristics and propagation.

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Comparative investigations on different types of inductors in single-phase inverter

2021-12-01 , Muhammad Zaid Aihsan , Ahmad Muhyiddin Yusof , Hasliza A Rahim @ Samsuddin , Baharuddin Ismail , Wan Azani Wan Mustafa , Mohd Saifizi Saidon , Muhammad Izuan Fahmi Romli

This 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.

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The effect of amplitude modulation index on harmonic distortion in unipolar SHEPWM inverter

2021-12-01 , Norhanisa Kimpol , Ahmad Muhyiddin Yusof , Muhammad Zaid Aihsan , Baharuddin Ismail , Mohd Hafiz Arshad , Mohd Saifizi Saidon

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%.

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Performance Analysis of Unipolar SPWM Inverter: Resistive load and Inductive load

2020-12-18 , Muhammad Zaid Aihsan , Ahmad Muhyiddin Yusof , Nur Irwany Ahmad , Mohd Saifizi Saidon , Habibah Mokhtaruddin , Diyya Hidayah Abdul Rahman , Wan Azani Wan Mustafa

This paper presents the performance analysis of the Unipolar SPWM Inverter for the resistive and inductive load testing. The common criteria reported in various technical papers where the resistive load will produce a unity power factor correction and lagging power factor behaviour for inductive load. This paper is to demonstrate the performance of both loads that are tested to the single phase Unipolar SPWM inverter under the modulation ratio of 0.8. The performances will be covered in term of the waveform behavior and THDv performance. The project are carried out through the simulation using PSIM software and real implementation to the real hardware. The selection of filter for this paper is the low pass passive LC filter.

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Modified Sinusoidal PWM Technique for Low Loss Inverter Application

2021-01-01 , Muhammad Zaid Aihsan , Hariz M.F. , Wan Azani Wan Mustafa , Ahmad Muhyiddin Yusof , Hasliza A Rahim @ Samsuddin , Alkhayyat A.

The efficiency of the main system is the most important concern for all power electronic engineers when designing power electronic converters. Normally there is a high switching state in conventional full-bridge inverter with sinusoidal pulse width modulation (SPWM), resulting in greater switching loss. This problem usually causes the efficiency of the inverter to fall to a certain level, resulting in poor inverter performance. In this study, the switching strategy can be changed to reduce the switching status while maintaining the original inverter frequency. The main goal of this research to reduce the switching loss of the inverter by modified the conventional SPWM to become a lesser switching state without losing the nature characteristic of the SPWM switching technique. The modified SPWM will be compared to the conventional SPWM in terms of switching loss and total harmonic distortion performance.

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