Liew Hui Fang
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Preferred name
Liew Hui Fang
Official Name
Hui Fang, Liew
Alternative Name
Fang, Liew Hui
Liew, Hui Fang
Liew, H. F.
Fang, L. H.
Main Affiliation
Scopus Author ID
55987930400
Researcher ID
AAF-4915-2021

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Total Harmonic Distortion Comparison Analysis between High-Power Density Inverter and Multilevel Inverter

2021-01-01 , Khalid K.A. , Muhammad Izuan Fahmi Romli , Liew Hui Fang , Muhammad Zaid Aihsan , Mohd Saifizi Saidon

The inverter is one of the most common things in converting electrical energy supply and it is a very important concept in the current modern electrical power system to utilize the maximum potential by generating the unit while considering the environment within the surrounding area and avoid pollution is the most ideal concept of energy management. The main purpose of this study is to consider which one of the inverters is more suitable for energy saving. There are two kinds of inverter that have been tested for this research which are the High-power density inverter (HPDI) and Multilevel inverter (MLI). In High-power density inverter (HPDI) it uses electrical components such as Insulated-gate Bipolar Transistor (IGBT) as the main component. As for the Multilevel inverter (MLI) it uses electrical components Metal- oxide-semiconductor field-effect-transistor (MOSFET) as the main component. Both inverters are being implemented and running by using MATLAB Simulink software. Besides that, the result is obtained by comparing the Total Harmonic Distortion (THD), the output of the waveform and energy efficiency for both inverters.

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Modelling and Analysis of Piezoelectric Cantilever for Kinetic Ambient Energy Harvesting

2024-01-01 , Izzati Kholid N.F. , Junita Mohd Nordin , Rosemizi Abd Rahim , `Aini Syuhada Md Zain , Liew Hui Fang , Alif M.H.

Wide bandwidth of vibration energy harvesters becomes one of most difficulties to their implementation but it is important to have cantilever beam that can tolerate wide variety of input frequency and able to harvest more kinetic energy. In this work, the piezoelectric material i.e. lead-zirconate-titanate (PZT), polyvinylidene fluoride (PVDF) and Aluminum Nitride (AlN) have been chosen to be analyzed. The piezoelectric cantilever beam structure, Unimorph type with dimension length of 40mm, 10mm width and thickness is 0.5mm has been proposed. The Finite Element Method (FEM) in ANSYS which consist of modal analysis, harmonic response analysis and statis structural analysis have been used to analyzed the characteristic of piezoelectric materials. Then, the full-bridge rectifier used to convert A-C to D-C sources using MATLAB Simulink and the experimental setup of the project was designed. The modal analysis result showed that PVDF material can applied greater maximum deformation than AlN and PZT material. The effect of dimension of cantilever beams of PVDF against natural frequency with different mode showed the natural frequency decrease when the dimensions of piezoelectric cantilever beam increase. On static structural analysis showed when the dimensions were increased, then the total deformation was decreased. Based on result of rectifying circuit for piezoelectric energy harvester using MATLAB Simulink, the positive and negative half cycle were conducted as theoretical studied. For the design verification, the experimental study showed the output voltage waveform is well regulated with minimum ripple.

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Review of Active Circuit and Passive Circuit Techniques to Improve the Performance of Highly Efficient Energy Harvesting Systems

2023-06-01 , Liew Hui Fang , Rosemizi Abd Rahim , Muhammad Izuan Fahmi Romli , Junita Mohd Nordin , `Aini Syuhada Md Zain

In piezoelectric energy harvesting systems, energy harvesting circuits are the interface between piezoelectric devices and electrical loads. The conventional view of this interface is based on the concept of impedance matching. In fact, in the power supply circuit can also apply as an electrical boundary conditions, such as voltage and charge, to piezoelectric devices for each energy conversion cycle. The major drawback of piezoelectric power harvesting have low-power relationships in systems within (in the range of μW to mW), then system also have significantly reduced any potential losses in circuits that make up the EH system, whereas other condition into careful selection of circuits and components can enhanced the energy harvesting performance and electricity consumption. In the study of energy harvesting systems, it is an energy harvesting system approach that using active and passive electronic circuit to control voltage and or charge on piezoelectric devices as proposed and review to mechanical inputs for optimized energy conversion. Several factors in the practical limitation of active and passive energy consumption, due to device limitations and the power efficiency of electronic circuits, will be introduced and have played an important role into to enhance optimum and increase efficiency of energy harvesting system.

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Publication

Review Article: Voltage Balancing Method for Battery and Supercapacitor

2023-02-01 , Nordin N.N.S. , Muhammad Izuan Fahmi Romli , Liew Hui Fang , Muhammad Zaid Aihsan , Mohd Saifizi Saidon

This paper examines several existing voltage equalizers techniques for energy storage system, with a focusing on batteries and supercapacitors. Due satisfy the demands, energy storage cells are often coupled in series/parallel. However, divergence of voltage distributed among cells produces the problems of voltage imbalance that affecting the ageing of energy storage system and solved through equalizers. Several assessments from features of topologies in voltage balancing circuit supplied primarily based total on a few attentions’ just like the effectiveness in balance and components. Voltage balancing is essentially separated into two categories: passive and active equalizers. Therefore, this paper studied and reviewed several topologies from both equalizer types with the sample result to verify the topology performance.

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A review on VFD Control and Energy Management System of Induction Motor for Electric Vehicle

2021-01-01 , Muhamad Akmal Aazmi , Muhammad Izuan Fahmi Romli , Muhammad Zaid Aihsan , Liew Hui Fang , Mohd Saifizi Saidon

This growing pattern of energy insufficiency will, of course, intensify in the future. According to the literature, variable frequency drives can save a lot of energy by changing the speed of the electrical motor mechanism (VFDs). The aim of these studies and analyses is to improve the efficiency of the electrical device system by using VFD control techniques. This paper outlines the principle of control mechanisms for induction motor drives, as well as their benefits and drawbacks. This paper is intended to serve as a one-stop shop for researchers interested in the topic. However, there appears to be no comprehensive review of Variable Frequency Drive (VFD) techniques for induction motor (IM) drives to resolve the need for a detailed insight into IM drives. Efficient control policies for induction motor drives provide a great opportunity for energy savings. As a result, research into the optimal operation of induction motor drives is escalating.

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Development of Highly Efficient Hybrid Kinetic-Solar Energy Harvesting System

2023-01-01 , Liew Hui Fang , Rosemizi Abd Rahim , Muhammad Izuan Fahmi Romli , Junita Mohd Nordin , `Aini Syuhada Md Zain , Mujahidin N.M.D.Z.

The development of sustainable and efficient energy harvesting systems has become critical in meeting global energy demands. Hence, the goal is to combine the kinetic energy created via footsteps alongside solar energy to maximize energy conversion and develop a sustainable power source. The research entails designing and optimizing the hybrid system, while selecting appropriate materials, and implementing advanced power management techniques for effective energy utilization. Therefore, in order to improve the efficiency of energy harvesting via the system, further research on voltage input for solar panels and piezo buzzer efficiency arrangements on slabs were conducted. Whereby, the tile cells generate electricity when someone walks across it. However, this energy output needs to be regulated using a voltage multiplier and an alternating current into direct current (AC-DC) converter. To accomplish this, an experiment on the outcomes for output parameter with stand-alone photovoltaic (PV) harvesting system in 6 days, piezoelectric (PZ) harvesting system with students weighing 60kg and 70kg in 14 steps and a power hybrid harvesting system was carried out. Overall, the findings of this study indicate that the proposed method is functional and can be verified by the system, with an average output of 9.46 V and 126.6 mA produced. Also, this study demonstrates the significant potential of hybrid kinetic-solar energy harvesting system in improving energy sustainability and promoting self-sufficient power generation for a variety of applications, including remote sensing, wireless sensor networks, and internet of things (IoT) devices, through experimental evaluations and simulations.

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Publication

Piezoelectric Array Configuration Technique into Enhance Power Catchment for Sound Energy Harvester System

2020-11-18 , Liew Hui Fang , Rosemizi Abd Rahim , Muhammad Izuan Fahmi Romli , Mohamad Zhafran Zakariya , Junaidah Ali Mohd Jobran , Norhanisa Kimpol

The objective of this study is to explore the harvest maximum output changes occurs in piezoelectric transducer when connected in different configuration to produce highest electricity consumption and generate sound energy harvesting system. Acoustic energy is a type of environmental energy source that can be extracted and converted into electrical energy for small-scale energy applications. In this study, the corresponding load resistance for single piezoelectric transducer is 4.5 k$\Omega$, together with a constant vibration source at a frequency of 68 Hz and a 1-g acceleration. The performance of output voltage and power of piezoelectric are evaluated and the optimum output is measured by depending on the connection of the piezoelectric transducer arrangement into series, parallel and series, and parallel which stimulated using Proteus software. The experiment result presented that, when have single piezo, 5 piezo connected in series, and 5 piezo connected in parallel, the output powers are 1.664 mW, 1.671mW and 7.676 mW, respectively. During the combination series and parallel connections, the output power of 3S1P piezo increases to 5.05mW. In a parallel configuration, the output voltage that produced is much higher than a piezoelectric transducer arrangement connected in series connection. The piezoelectric transducer that connected in parallel configurations increases its voltage output from 2.83 V to 13.05 V with the same polarity. The arrangement of piezoelectric transducer in parallel configuration is affordable, with its higher production of a higher power output compared to the arrangement of piezoelectric transducer in series connection. Whereas in terms of power output, the maximum power remains constant in the range of 1.665 to 1.671 mW when three transducers are in series configuration connection with the same polarity. In conclusion, the proper implementation of the piezoelectric array configuration is needed in order to operate the minimum energy for low load devices and promise to accomplish generated optimum power output in harvester system.

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Direct torque control of induction motor with different energy storage for electrical vehicle (EV) application

2021-12-01 , Aazmi M.A. , Muhammad Izuan Fahmi Romli , Muhammad Zaid Aihsan , Liew Hui Fang , Mohd Saifizi Saidon

Energy demand worldwide is rising at an unprecedented pace. This has already shown its impact on the depletion of energy sources and environmental issues (global warming and the weakening of the ozone layer). This growing pattern of energy insufficiency will, of course, intensify in the future. Referring to the literature, significant energy savings can be achieved by controlling the speed of the electric motor system using variable frequency drives (VFDs). Efficient control of induction motor drives provides an excellent opportunity for energy savings. As a result, research into the optimal operation of induction motor drives is escalating and mainly focuses on the Direct Torque Control (DTC) control technique on improving the dynamic operation of torque control. However, the study on the type of energies on improving the dynamic response is least reported. This paper will study the effect of different energy supplies on the dynamic response of torque performance. The standard DC battery and supercapacitor will be used to energize the induction motor through the three-phase inverter and controlled with the DTC control scheme. The results are validated through MATLAB Simulink and it shows the supercapacitor has the better dynamic response in torque response compared to the standard DC battery. The comparative results are presented in a proper mannered way.

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