Torque improvement of PM motor with semi-cycle stator design using 2D-finite element analysis

This paper presents sizing approaches to improve output torque performance in PM motor when partial stator body is removed. As the output torque performance is directly proportional to the electric loading, Q, modification on stator geometry affects the output torque performance and special procedures have to be taken to restore the desired output torque capability. Influences of split ratio, tooth body width, airgap and magnet thickness of  magnet in PM motor with asymmetry stator design are carried out and the performance verification are referred to the back-emf, average output torque, torque ripple as well as cogging torque. From the investigation using 2D-Finite Element Analysis, optimum size of tooth body width and optimum number of coil turns result better output torque while other sizing approaches result no significant change as quick saturation took place

Average dynamical frequency behaviour for multi-area islanded micro-grid networks

A micro-grid is a part of power system which able to operates in grid or islanding mode. The most important variable that able to give us information about the stability in islanded micro-grid network is the frequency dynamical responses. The frequency analysis for multi-area micro-grid network model may involve a complicated of mathematical equations. This makes the researcher intending to omit several unnecessary parameters in order to simplify the equations. The purpose of this paper is to show an approach to derive the mathematical equations to represent the average behavior of frequency dynamical responses for two different micro-grid areas. Both of networks are assumed to have non-identical distributed generator behavior with different parameters. The prime mover and speed governor systems are augmented with the general swing equation. The tie line model and the information of rotor angle was considered. Then, in the last section, the comparison between this technique with the conventional approach using centre of inertia (COI) technique was defined

Improved Magnetic Behavior Of Hemicycle PM Motor Via Stator Modification

This article investigates electromagnetic performance of a hemicycle PM motor by introducing a little modification on both ends of a hemicycle stator. Prior to the investigation, an analytical model for the hemicycle PM motor weight is derived analytically for the purpose of comparison with a conventional design. Both motor weights are then verified and the hemicycle motor is found to have lighter weight than the conventional design. By having a proper design modification, an optimum motor performance is achievable due to improved magnetic permeance. Two designs that have different arc angle; i) 180° (188.5 mm arc length) and ii) >180° (204.2 mm arc length) are the subjects of investigation. It is found that a hemicycle PM motor in which arc angle >180° results maximum torque average with the smallest torque ripple and smallest cogging torqu

Design Of A Linear DC Motor For High Thrust Constants Characteristics

Traditionally a linear motion system consists of a rotational motor and motion translation component. However, the traditional systems inherit several drawbacks that contribute into operational limitation. Currently, use of a linear motor is seen as an alternative to produce direct linear motion without use any motion translation. Linear DC Motor (LDM) is one type of linear motor. Previously, a LDM has been developed to be use in a linear displacement system. Based on experimental result, it could achieve a desired displacement with fast settling time and low overshoot. However, in order to improve the system performance especially in term of time response, a new LDM need to be designed. In this paper, a LDM for similar application was designed. The shape of the LDM has been change from a rectangular to quarter circle due to changes in shape of permanent magnet. Furthermore, material of the permanent magnet also has been changed from ferrite to NdFeB to increase the magnetic flux density in air gap. Based on the designed, the LDM has produce about 3.1 N/A and 35.12 ms in term of thrust constant, kf and mechanical time constant, Tm respectively. In comparison with previous LDM, it only produced about 1.6 N/A and 111.72 ms in term of thrust constant, kf and mechanical time constant, Tm respectively

Enhanced Performance of DTC-DSC of Induction Machine utilizing 3-Level Cascade H-Bridge Multilevel Inverter

The paper presents a new 3L DTC-DSC scheme for induction motor driver by selecting proper voltage vector for medium and high application. In conventional 3L DTC two different voltage vectors are assigned to vary flux for low speed, medium speed and high speed applications. This paper purposes a scheme for low speed operation of induction machines by using the same technique as conventional 3L DTC. However for a high speed operation, only a single voltage vector is applied thus resulting dodecagon flux locus.The new scheme also improves the torque capabalities and the dynamic of torque performances

Characteristics of ionically conducting jatropha oil-based polyurethane acrylate gel electrolyte doped with potassium iodide

Currently, there is a growing trend of using bio-based materials from renewable resources in the construction of polymer electrolytes. In this study, a gel polymer electrolyte from Jatropha oil-based polyurethane acrylate (PUA) was prepared by doping the PUA with various concentrations (0–30 weight%) of potassium iodide (KI) salt. The PUA gel electrolyte was characterized by Fourier-transform infrared spectrometry (FTIR), thermal analysis and electrochemical analysis was performed by using electrochemical impedance spectroscopy. Subsequently, the dielectric properties of the gel polymer electrolyte were studied. A conductivity of 1.59 × 10−4 S cm−1 was achieved for the PUA incorporated with 25 weight% KI at room temperature. The dielectric study indicated the non-Debye nature of the materials. It has been shown, via transference number measurement that the conducting species in this work were predominantly ions, with only 4% contribution from electrons. An electrochemical stability window of 2.0 V was obtained by using linear sweep voltammetry for the highest conducting gel electrolyte

Equilibrium and kinetic behavior on cadmium and lead removal by using synthetic polymer

It is known that synthetic polymer plays a big role in various applications. One of its potentials is to remove heavy metal ions through single batch adsorption. Adsorption behavior and mechanism of synthetic polymer are the two main focuses in this research. The synthetic polymer of Poly(AN-co-AA) has been successfully polymerized, modified with hydroxylamine hydrochloride and removed Cd2+ and Pb2+. The poly(AN-co-AA) and amidoxime (AO) modified poly(AN-co-AA) were characterized by Fourier Transform Infrared Analysis (FTIR), microanalysis, Scanning Electron Microscopy (SEM) and Thermogravimetry (TGA). At pH 9, the percentage removal for Cd2+ (90%) and Pb2+ (98%) were the highest with adsorbent dosage at 4 gL−1 and 8 g L−1, respectively. The experimental data for Cd2+ (20 mg g−1) and Pb2+ (125 mg g−1) were fitted well by Sips and Freundlich isotherms model, respectively. The adsorption rate for both Cd2+ and Pb2+ were stated by using Lagergren pseudo-first order

Total Power Deficiency Estimation Of Isolated Power System Network Using Full-State Observer Method

An isolated electrical network with an independent local distributed generator is very sensitive towards the contingencies between load demand and supply. Although the network system has less complexity in term of structure, its stability condition is crucial due to its stand-alone operating condition. The total power deficit in the network gives the important information related to the dynamical frequency responses which may directly affect the system's stability level. In this paper, the approach to estimate the total power deficiency for the isolated electrical network was presented by utilized the Luenberger observer method. Although the power deficit is not the state variable in the network mathematical model, the solution of estimation problem was feasible by introducing the new variable using additional dummy system. The simulation was carried out by using MATLAB/Simulink environment and the designed estimator was verified using multifarious load demand changes. The results show that the estimated signal was successfully tracked the expected actual signal with minimum error