Leong Jenn Hwai , Jenn
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Leong Jenn Hwai , Jenn
Official Name
Jenn, Hwai Leong
Alternative Name
Leong, Jenn Hwai
Hwai, L. J.
Leong, J. H.
Hwai, Leong Jenn
Hwai Leong, Jenn
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Scopus Author ID
56572199100
Researcher ID
CUO-1132-2022

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  • Publication
    Design and Optimization of Electromagnetic Torque for a Surface-Mounted PMSM by using Subdomain Model and GA in Electric Vehicle Application
    ( 2021-01-01)
    Syauqina Akmar Mohd Shafri
    ;
    Tiang Tow Leong
    ;
    Tan C.J.
    ;
    Ishak D.
    ;
    Mohd Saufi Ahmad
    ;
    Leong Jenn Hwai , Jenn
    ;
    Ong Hui Lin
    This paper presents a highly structured optimization strategy for 12-slot/8-pole surface-mounted permanent magnet synchronous machines (SMPMSM) with radial magnetization pattern. The main goals of the optimization process are to determine the optimal motor geometry, and achieving the minimum torque ripple and maximum average electromagnetic torque, simultaneously. The first function is used to obtain the maximum electromagnetic torque, and thus obtaining higher efficiency and the second function is used to achieve the minimum torque ripple. A computing framework that ensemble the genetic algorithm (GA) and subdomain model (SDM) with weighted equations is proposed to determine the optimal design of SMPMSM. After the optimization process, the optimal design of PM motor demonstrates much lower torque ripple with reasonable electromagnetic torque as compared with that of the initial design. The comparison of parameters and motor performances between the initial and the optimal designs of 12-slot/8-pole PM motors with the computing framework are validated in terms of electromagnetic torque under BLAC operation using SDM. Thus, the framework of SDM and GA is verified in reducing the usage of magnet materials and the electromagnetic torque ripple of SMPMSM, which is highly viable for electric vehicle. Therefore, the proposed ensemble framework of GA and SDM can determine the optimal settings of geometry design for SMPMSM in order to produce optimum motor performance.
      1
  • Publication
    Optimization Design of the Electromagnetic Torque for Surface-Mounted PMSM using GA and Finite Element Analysis for Electric Vehicle
    ( 2021-01-01)
    Edric Wong Wee Ming
    ;
    Tan C.J.
    ;
    Leong Jenn Hwai , Jenn
    ;
    Syauqina Akmar Mohd-Shafri
    ;
    Ishak D.
    ;
    Ong Hui Lin
    ;
    Tiang Tow Leong
    ;
    Mohd Saufi Ahmad
    This paper presents an optimization design for a three-phase 12 mathrm{s}/8 mathrm{p} surface-mounted permanent magnet synchronous machine (SMPMSM) with a RM pattern applied in the electric vehicle by using the computing framework of finite element analysis (FEA) and genetic algorithm (GA). The framework is to determine the optimal settings of permanent magnet (PM) motor for higher average electromagnetic torque (T_{em_{-}avg}) and lower its ripple (T_{em_{-}rip}). Several motor performances are investigated for the initial and the optimal designs of PM machines during open-circuit and on-load conditions, i.e., magnetic field distribution across the motor, magnetic flux density distribution in the mid air gap, phase back-EMF, electromagnetic torque, and its ripple through FEA. The magnet pole-arc and slot opening angle of the PM motor are taken into consideration. The T_{em_{-}avg} and the T_{em_{-}rip} are employed to formulate the computing equations to determine the objective function, which is used to search the optimal settings of PM motor in GA framework, where the fitness value produced by the computing framework is further evaluated. The comparison of parameters and motor performances between the initial and the optimal designs of 12s/8p PM motors with the GA framework are validated in terms of electromagnetic torque under BLAC operation using FEA. Therefore, the framework of FEA and GA is verified in reducing the usage of magnet materials and the electromagnetic torque ripple in the design of SMPMSM, which is highly viable for electric vehicle.
      1
  • Publication
    Accurate Simplified SPWM Control Strategy for Single-Phase Voltage Source Inverter under Varying Grid Conditions
    ( 2023-01-01)
    Ahmad N.S.
    ;
    Madzlan N.A.
    ;
    Ahmad Afif Nazib
    ;
    Leong Jenn Hwai , Jenn
    A single-phase Voltage Source Inverter (VSI) controller with minimal complexity and computational burden is considered attractive. However, the accuracy of its power injection should not be compromised. The simplified sinusoid pulse width modulation (SSPWM) control strategy achieves this simplicity, but the accuracy of its power demands under varying grid conditions is yet addressed. This paper now investigates the power demand accuracy of the SSPWM control strategy. An improved strategy is then proposed by incorporating an optimised Proportional Integral (PI) current regulator within the simplified control strategy to achieve accurate power demands under varying grid conditions. The strategy has been verified via detailed simulation investigations of a single-phase VSI under varying grid conditions. The simulation shows the proposed control structure is 5.1% better than the SSPWM for the injected real power.
      9  29
  • Publication
    Fuzzy Logic Cascaded Current Control of DC Motor Variable Speed Drive using dSPACE
    ( 2023-01-01)
    Ahmad Firdaus Ahmad Zaidi
    ;
    Ni L.P.
    ;
    Leong Jenn Hwai , Jenn
    ;
    Syahrul Ashikin Azmi
    ;
    Kamarulzaman Kamarudin
    ;
    Hasimah Ali
    ;
    Mohd Shuhanaz Zanar Azalan
    ;
    Siti Nurul Aqmariah Mohd Kanafiah
    ;
    Jusman Y.
    Two-wheel e-scooter falls under low power segment for Battery Electric Vehicle (BEV) and has gain more popularity in urban commuting. Most entry level e-scooter is still powered by DC motor due to low cost and ease of control. However basic open-loop DC Motor control employed through throttling is plugged with limited efficiency, precision, and range of speed control. Closed-loop control enables real time adjustment according to preset speed which becomes handy during auto cruising. To ensure good dynamic response, improved robustness and stable wide speed control range, a good control scheme for the motor is essential. In this project, a variable speed control scheme, namely fuzzy logic cascaded current control system was designed using MATLAB Simulink, comprising speed control loop and a current control loop 185 W Separately Excited Brushed DC Motor. The proposed control system was tested on hardware using dSPACE DS1104 platform. The system's output speed is obtained using an incremental encoder, while the output current is measured with a current sensor. Subsequently, the control system's stability, robustness, and dynamic performance were evaluated by driving the system on 120 W electrical load at varying speed. The system performance has proved superior to closed-loop by 70% on low speed ripple reduction and is on par with PI cascaded current control scheme.
      1
  • Publication
    Design of 30 kW three-phase string inverter using simulink
    (IOP Publishing, 2020)
    Fijay Fauzi
    ;
    N Yasin
    ;
    Leong Jenn Hwai , Jenn
    ;
    Baharuddin Ismail
    This paper presents the design and simulation of a 30 kW DC to AC inverter. The inverter is designed based on the Zeverlution Pro 33K three-phase DC to AC inverter. Currently, there are 6 units of the inverters installed at 180 kW solar power plant located at Mukim Utan Aji, Perlis. So, in this paper, the results from the computer simulation will be compared to the site measurement conducted from this power plant. In this design, pulse with modulation (PWM) is used as the switching technique. Even though PWM offers the ease of LC filter design and low Total Harmonic Distortion (THD), the voltage amplitude of the sine wave output fails to achieve the required national grid parameters, i.e. 240 Vrms. To overcome this problem, a three-phase transformer has to be incorporated in the design to obtain the desired outputs. Results from computer simulation using SIMULINK show that the targeted AC parameters for all phases were achieved after comparing with the site measurement.
      14  2
  • Publication
    Optimal Design of SMPMSM Using SD-model based on Genetic Algorithm
    ( 2021-01-01)
    Syauqina Akmar Mohd-Shafri
    ;
    Tiang Tow Leong
    ;
    Tan C.J.
    ;
    Ishak D.
    ;
    Mohd Saufi Ahmad
    ;
    Leong Jenn Hwai , Jenn
    ;
    Ong Hui Lin
    This paper deals with an optimal design of a surface-mounted permanent magnet synchronous machine (SMPMSM) with an exact analytical subdomain model by using a genetic algorithm method. To analyze the characteristic of permanent magnet (PM) motors, the classical optimization method, such as the finite element method (FEM), is intensively used. However, FEM has several time problems that require a longer computational time to evaluate the performance of PM motors. This problem can be overcome by using a genetic algorithm (GA) method combined with a subdomain model (SD), which developed an improved performance of SMPMSM, for instance, total harmonic distortion (THDv) and cogging torque. In this design, a three-phase 12-slot/8-pole PM motor is established with an exact SD model with RM and PaM magnetization patterns. Then, the GA ensemble with SD model to search the optimality of SMPMSM machine design. In the final analysis, the optimal new design of SMPMSM demonstrated by comparing with the initial design that is investigated by FEM. The result of induced back-EMF, cogging torque, total harmonic distortion, and magnetic flux density of optimal design is compared with the initial design to show the advantages of GA optimization method.
      1  36
  • Publication
    Assessment of Control Drive Technologies for Induction Motor: Industrial Application to Electric Vehicle
    ( 2021-06-11)
    Ahmad Firdaus Ahmad Zaidi
    ;
    Syahrul Ashikin Azmi
    ;
    Kamarulzaman Kamarudin
    ;
    Leong Jenn Hwai , Jenn
    ;
    Hasimah Ali
    ;
    Mohd Shuhanaz Zanar Azalan
    ;
    Zamri Che Mat Kasa
    Nowadays electric vehicle has increasingly gained much popularity indicated by growing global share market targeted at 30% by 2030 after recording 7.2million global stock in 2019. Compared to Internal Combustion Engine (ICE) counterpart, Battery Electric Vehicles (BEV) produce zero tailpipe emission which greatly reducing carbon footprints. Induction motor has been widely used and its control technology has evolved from scalar type volt/hertz to recent predictive control technology. This allows induction motor's application to expand from being the workhorse of industry to become prime mover in electric vehicle, where high performance is expected. Among vector control scheme, Direct Torque Control (DTC) has gained interest over Field Oriented Control (FOC) with simpler structure, better robustness and dynamics performance yet suffer from high torque and flux ripple. In electric vehicle applications, high ripple at low speed is highly undesirable, potentially causing torsional vibration. High performance control requires speed sensor integration, which often increase complexity in the design. The work aims to review the best control technology for induction motor in electric vehicle application through performance parameter evaluation such as improvement on dynamic response, torque and flux ripple reduction, and component optimization. Several arise issues in motor control and possible methods to circumvent are highlighted in this work. In conclusion, model predictive torque control (MPTC) is the most promising scheme for electric vehicle with excellent dynamic response, good low speed performance, and 50% torque ripple reduction compared to conventional DTC and potential integration with sliding mode observer for sensorless solution.
      1  38
  • Publication
    Design and Development of Cascaded Current Control in DC Motor Variable Speed Drive using dSPACE
    ( 2023-01-01)
    Ahmad Firdaus Ahmad Zaidi
    ;
    Davendren T.
    ;
    Syahrul Ashikin Azmi
    ;
    Leong Jenn Hwai , Jenn
    ;
    Kamarulzaman Kamarudin
    ;
    Hassan A.
    ;
    Hasimah Ali
    ;
    Mohd Shuhanaz Zanar Azalan
    ;
    Normahira Mamat @ Mohamad Nor
    Even today, DC motors are still used in variety of applications, including home appliances, transportation, as well as industrial crane and rolling machine. However, achieving precise speed and torque control in DC drives at industry level could be challenging, as instability and reduced efficiency remains at large. This project focuses on developing a cascaded control system for a Separately Excited Brushed DC motor using dSPACE platform. The cascaded control system, designed using MATLAB Simulink, incorporates a proportional-integral (PI) controller at the speed loop and a Hysteresis controller at the current loop to improve robustness and dynamic performance. The experimental setup utilizes the dSPACE 1104 platform, an asymmetric bridge converter board, gate driver, and electrical load. Speed measurement is done using an incremental encoder, while current is measured using the ACS712 current sensor. The drive system was tested in alternate low and high speed cycle on various load level to test for stability, robustness and dynamic performance. The proposed control system was compared with PI-closed-loop control and open-loop control determine the best drive performance. Experimental results showed significant improvement in term of transient response and ripple reduction of speed and current for proposed cascaded current control over the closed-loop design.
      6  33
  • Publication
    Effect of DC voltage source on the voltage and current of transmitter and receiver coil of 2.5 kHz wireless power transfer
    ( 2020-04-01)
    Butar-Butar A.H.
    ;
    Leong Jenn Hwai , Jenn
    ;
    Muhammad Irwanto Misrun
    A solenoid supplied by alternating current (AC) voltage generates electromagnetic which has a field area depends on the level of supplied voltage and current flows through the solenoid. The electromagnetic filed can be captured by the other solenoid in the field area. This concept can be applied in a wireless power transfer (WPT) as presented in this paper. The WPT has transmitter coil and receiver coil which each has form of solenoid. The transmitter coil is connected a half bridge circuit to generate AC voltage on the transmitter coil which transferred to the receiver coil. In the experimental set up, the receiver coil is supplied by DC voltage source and it is changed to observe its effect on the voltage and current on the transmitter and receiver coil of the WPT system.
      23  1
  • Publication
    Investigation the optimum performance of the surface-mounted PMSM under different magnetization patterns
    ( 2020-01-07)
    Akmar Mohd-Shafri, Syauqina
    ;
    Tiang Tow Leong
    ;
    Ishak D.
    ;
    Leong Jenn Hwai , Jenn
    ;
    Jun Tan C.
    ;
    Ong Hui Lin
    This paper investigates the influence of different magnetization patterns on the performances of the surface-mounted permanent magnet synchronous machines (SMPMSMs). Three magnetization patterns are employed, which are radial, parallel, and ideal Halbach magnetizations. These magnetization patterns are applied to 9-slot/10-pole and 15-slot/4-pole permanent magnet (PM) machines. The PM machines are designed and simulated by using Opera 2D finite element. The performances of three PM motors, such as airgap flux density, phase back-EMF, and cogging torque, are evaluated under the influence of different magnetization patterns. The total harmonic distortion of phase back-EMF (THDv) for the motors are investigated. The PM motors with ideal Halbach magnetization provide the lowest cogging torque and the lowest total harmonic distortion of phase back-EMF. Besides that, the optimum setting of the magnet pole-arc can reduce the total harmonic distortion of phase back-EMF and achieve lower cogging torque. The optimum magnet pole-arc produced by radial magnetization in 9-slot/10-pole motor is 24.8 mech., with cogging torque of 0.45 Nm, and THDv of 2.69 %. Meanwhile, the optimum magnet pole-arc produced by parallel magnetization in 9-slot/10-pole motor is 26.0 mech., with cogging torque of 0.41 Nm, and THDv of 2.00 %.
      12  40