Taib Ibrahim

Design and modeling of a single-phase linear permanent magnet motor for household refrigerator applications

In this paper, three novel designs of linear permanent magnet motors (LPMM) having moving magnets armature, are proposed for driving a direct drive linear reciprocating compressor in household refrigerator. The designs are then compared, including the configurations and static characteristics based on finite element analysis (FEA). In contrast to a conventional reciprocating compressor, a direct-drive linear compressor in which the piston is driven directly by a linear motor (LM) and resonant springs is considered a positive displacement. The analysis on performance of LPMM using the proposed designs is carried out on the magnetic flux-lines, magnetic field intensity, magnetic flux density, back-EMF and thrust force. The extensive simulation results indicate the effectiveness of the proposed designs.

Portable and pico-scale linear generator for wave energy conversion

This paper presents the design of linear permanent magnet generator for wave energy conversion. The main focus is to design a linear generator which is simple, lightweight and produce 1000 W electric power. Various types of linear generators are studied such as; Transverse flux, vernier-hybrid and iron-cored. The air-cored linear permanent magnet generator is selected as it eliminates cogging force and problems present in existing linear generators. Three designs of proposed linear generator are presented. Finite Element Analysis (FEA) is used to determine the electromagnetic performance of the proposed designs of generator. The results for all designs shown are as per expected.

Linear permanent magnet motor for reciprocating compressor applications

This paper investigates the performance of a three designs of tubular linear permanent magnet motors (TLPMMs) with quasi-Halbach magnetized moving-magnet armature and slotted stator with a single-slot. The motors were developed for reciprocating compressor applications such as household refrigerators. The three designs have different magnet shape structures, and the stator core of all designs have employed a soft magnetic composite (SMC) material, Somaloy 700. Based on finite element analysis (FEA) an extensively analysis on the opencircuit magnetic field distribution, back-EMF, thrust force, fluxlinkage, winding inductance and cogging force in the three designs have been established. The simulation results indicate the effectiveness of the designs to drive a linear reciprocating compressor in household refrigerators, and also the simulation results have shown the superiority of the two designs with T-shape and trapezoidal magnet configurations, over the TLPMM with conventional rectangular magnet. Moreover, the permanent magnets (PMs) array arrangement has significant effects on the motor performance.

Investigation and development of remote vital signs monitoring device using wireless communication

Monitoring applications have been deployed throughout the years using either wired or short and long distance wireless technology. The wireless technologies itself have been developing and on increasing trends throughout the years. This study discusses on the comparison on two types of wireless technologies to be deployed in the healthcare industries for monitoring patients vital signs, which are, heart rate and temperature. RF and Zigbee technologies were used in series of experiments to monitor these vital signs. It was found that the Zigbee technology produced reliable and accurate data with longer transmission range. This study also discusses on development of the device from designing until the printed PCB version. Series of tests were conducted using the variations of parameters and Zigbee technology produces stable and similar output vital signs reading compared to the conventional device.

Heat Energy Harvesting for Portable Power Supply

Heat Energy Harvesting for Portable Power Supply (PosHEAT) is the renewable energy which produces electrical energy from waste heat. PosHEAT has many attractive features, such as reduced maintenance, completely silent, no moving parts and no emission to generate electricity. Based on Thermocouple concept, the greatest material to produce more power is Seebeck made from Bismuth Telluride (Bi2Te3). PosHEAT will convert heat energy to electrical energy when there is temperature difference between the two sides. Temperature play the main role in this project to produce power. This paper highlights the Seebeck theory and electrical system design for storage of the energy.

Modeling of a tubular permanent magnet linear generator for wave energy conversion using finite element method

This paper presents the modeling process of a tubular permanent magnet linear generator for the wave energy conversion system. Two types of linear generator technology namely the planar and tubular with different on translator, stator and magnet arrangement are identified but due to the high detent force, low flux density and high fabrication cost, tubular excogitation is preferable. Three linear permanent magnet generators with different types of permanent magnet layout have been proposed. Preliminary results for the number of turns and varying speed proportional with induced voltage and open circuit test are demonstrated and discussed are shown to be as expected. Based on the overall findings, the shape of permanent magnet in the excogitation affects the performance of the generator.

Automated Electrical Protection System for domestic application

Power outage is a common problem when there are electrical faults occurred, which would lead to discontinuity of electrical supply to domestic building. For domestic consumers, power continuity is very important since some of the appliances such as refrigerator, aquarium and alarm system require a continuous electrical supply. However, fault occurred in the system will trip the earth leakage circuit breaker (ELCB) and disrupt the supply to all the appliances. Fault may occur due to short circuit, ground fault or overloading. Thus, the aim of this paper is to develop an automatic system for single-phase power system to overcome the problems. The automatic system is able to detect and isolate the fault in order to ensure the power continuity in the building.

Hybrid energy from exhaust system

Currently, there are no motorcycles in the market that provide electrical charging for mobile devices that are being used widely in the modern world. This paper demonstrates the concept of energy recovery through the use of a hybrid system in the exhaust pipe of a motorcycle to charge mobile devices. The term hybrid energy refers to an application that uses two energy conversion devices, that when combined, will produce an output energy enough to meet the load. The hybrid energy used here is comprised of two renewable energy sources, wind and heat energy. Both the sources are captured from the exhaust pipe of the motorcycle and are converted to electrical energy. A booster circuit is used to boost the voltage produced before feeding it into a battery to be stored until needed. A user will then be able to charge a mobile device by connecting it to the battery. A toggle switch will determine the battery mode, whether to charge the battery through the hybrid system, or to discharge it in order to charge the mobile device. This paper focuses on the wind turbine design, the DC generator used, the thermoelectric unit, the exhaust pipe modification, the hybrid circuit and the results of the charging system through testing. The performance of the device is proven as the more rpm is introduced, the more voltage is produced.

Optimization of iron-cored linear motor with trapezoidal magnet using finite-element analysis

This paper deals with the design optimization of iron-cored linear motor with trapezoidal permanent magnets (PMs) configurations. Such motor is a short-stroke, single-phase tubular linear permanent magnet motor (TLPMM). The motor equipped with a quasi-Halbach magnetized moving-magnet armature and stator with a single slot and a single coil. The predicted magnetic field distribution in the airgap, flux-linkage and winding inductance of the proposed design, are already presented in a previous papers. The design optimization of the proposed TLPMM for the leading design parameters has been conducted. The optimal values of the axial length of the magnet at the center to the pole-pitch ratio and the split ratio are found to be 0.64 and 0.52. The efficiencies at these optimal values are 93.13 % and 93.8 %, respectively. Also, the angle of the trapezoidal PMs is optimized, and it is found to be equal 60°. Meanwhile, the losses of the motor, such as iron loss and copper loss are predicted and analyzed. The finite-element analysis (FEA) was successfully implemented for this study.

Design of converters for wave energy conversion system

This paper presents the design and simulation of DC-DC boost converter model and three phase DC-AC inverter model used in wave energy conversion system. The converters have been developed in MATLAB/SIMULINK environment. The two converters have been connected together through the DC link to model the DC-DC-AC converters. The DC-DC-AC model has been created in order to actualize the conversion from DC to DC and DC to AC. The output voltages of the models have been reported. The THD for the phase to phase voltage and phase to neutral at the inverter side and at the load side have been compared before and after adding the LC filter.