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In this paper, the CMG is re-condition so that the pole piece act as the outer rotor instead of surface mount PM. This magnetic coupling of the CMG is similar to the conventional CMG which uses harmonic to transfer the torque and speed from the inner rotor to the outer rotor. The working principle of the proposed CMG is derived analytically and simulated using finite element software. For this recondition, the PM at the outer section become stationary hence, retaining sleeve can be removing. The proposed MG produced 18% higher average torque than the conventional MG with drawback in torque ripple. The proposed CMG also produce higher gear ratio than the same pole pair of conventional CMG.

Recently, a three-phase Field Excitation Flux Switching Motor (FEFSM) using salient rotor has been introduced, suitable for high torque, high power as well as high speed diverse performances due to their advantages of easy rotor temperature elimination and controllable field excitation (FE) flux. However, existing FEFSMs are found to have low torque performance as the salient rotor structure has caused longer flux path, and consequently weak flux linkage. Therefore, a new structure of a single-phase FEFSM using segmental rotor and non-overlap windings is proposed. There are two valuable findings found in this topology, first is less copper loss due to the non-overlap windings between armature and FE coils, and secondly the segmental rotor structure has produces shorter flux path to produce high torque, less rotor weight as well as robust rotor at high speed condition. Flux linkage, back-emf, average torque and output power characteristics of the initial and optimized designs have been investigated and compared using 2D Finite Element Analysis (2D-FEA) through JMAG Designer version 15. Based on the 2D-FEA analysis, the average torque has increased by 81.3% to 1.65 Nm, while the output power of 466.5 W, increased of 68.2%. In conclusions, a FEFSM using segmental rotor and non-overlap windings is considered as the best single-phase motor due to their optimal performances and less copper loss.

Nowadays, XLPE cable has been widely used because it has better resistance than other cables. XLPE insulation has unique features including a high dielectric strength and high insulation resistance. A lot of researches based on hardware and software have been conducted to prove the effectiveness of XLPE cable such as AC and DC applications and Space Charge Distribution measurement under HVDC at High Temperature. This research focused on analysis of space charge and electric field on XLPE cable with effect of non-uniform contamination layer by using Quickfield Software. Non-uniform contaminations have been applied along XLPE cable using Arsenic Tribromide (AsBr3), Boron Bromide (BBr3), Ethylene Dichloride (CH2C1), Formic Acid (CH1O2), Formamide (CH3NO) and Alcohol element. Presence of these contamination elements represent of underground contamination. The size and layer of the contamination were non-uniform type. From the results, it is shown that lower dielectric constant of contamination will affect more on charge of XLPE insulation. As a conclusion, it can be seen lower dielectric constant value of contamination element greatly affecting the performance of XLPE insulation. Furthermore, size of contamination also influences the content of charge in contamination where the bigger the contamination size, the more charge contained in the contamination.

Oils acts as insulation and cooling agent in the transformer. Petroleum-based oils are widely used in transformers due to their qualified properties as good insulation materials. Unfortunately, the used of petroleum-based oils has adverse effects on environment in the event of any failure to transformers such as tank leakage or explosions. Therefore, researchers have been studied and have found environmentally friendly oil that is suitable as substitutes in transformer. Thus, breakdown voltage tests using direct current and alternating current with the addition of different water content were performed to identify the potential of palm oil and coconut oil in the transformer isolation system. Refined, Bleached and Deodorized oil (RBDPO) and coconut oil samples were selected to be test in this study. The oil samples were test by varies the gap distance of test cell electrode and the level of water content. As a conclusion, RBDPO oil has greater breakdown voltage test under DC breakdown voltage test in term of increment of the gap distance.

In the past, 4S-10P E-Core Hybrid Flux Switching Motor (HFSM) had been studied. However, the motor suffers high cogging torque but it has high performance in terms of high power and high torque at high speed. Therefore, this paper is proposing the cogging torque reduction techniques to minimize the cogging torque. The high cogging torque gave an undesirable effect during low operating speed of the motor. In order to tackle the issue, the cogging torque mechanism in equation is laid out as a form of reference. Then the reduction techniques employed on the designs and analyzed with Finite Element analysis (FEA) in JMAG. The results show the cogging torque of the optimized design is 44.45% of the motor torque. Besides, the techniques employed to identify which techniques gave the most cogging torque reduction and analyzed the geometrical difference using the cogging torque mechanism. Finally, the analysis is discussed based on the modified geometrics.

Recently, permanent magnet synchronous machine (PMSM) having the diameter of 11inches was successfully developed and installed in electric scooter vehicle (ESV) for propulsion. It consists of segmented stators of 24 armature slots and 100 pieces of permanent magnet of 2 kg weight mounted on rotating rotor. Upon the huge amount of materials and permanent magnet used, PMSM produced 110Nm only. Looking at the size, this torque is low and could not sustain acceleration for long distance travels. To overcome the challenge of low torque, this paper presents a new machine type, flux switching motor (FSM) with 1 kg weight of permanent magnet flux source employing segmented outer rotor. Six ranges of split ratio of 0.80-0.85 for outer rotor 24slot-14pole FSPM motor configurations were designed and compared. The 2D-FEA by JMAG software version 14 is used to examine its performance in term of flux linkage, cogging torque, back-emf and average torque which the structure with split ratio of 0.85 took lead by securing highest torque profile of 209Nm. It also achieved low cogging torque to operate in safe region. In conclusion, appropriate split ratio significantly enhances high torque capability of permanent magnet flux switching motor for electric scooter propulsion.

This paper presents performance analysis of 12Slot with various rotor pole numbers Hybrid Excitation Flux Switching Machine (HEFSM) for Hybrid Electric Vehicles (HEVs) application. HEFSM has carried out by combining the advantage of Permanent Magnet (PM) machines and DC Field Excitation Coil (FEC) synchronous machines. Previously, most of HEFSM structure having FEC windings in theta direction that create a problem of flux cancellation that will affect the performances of the machine. Thus, a design of 12Slot HEFSM with FEC wounded in radial direction is proposed to eliminate the flux cancellation effect. At first, armature coil arrangement test at no-load condition is conducted to analyze PM flux. Furthermore, induced voltage and cogging torque at open circuit condition are investigated based on 2D finite element analysis (FEA). Finally, torque and power performances are also examined at maximum FEC and armature current densities. The outcomes demonstrate that 12S-14P configuration has the highest PM flux linkage, torque, power and less distortion of back-emf waveform which are required to be used as a motor in HEVs. The highest torque and power achieved are 220.15Nm and 92.45kW, respectively.

On the basis of analysis of dq model of permanent magnet synchronous motor (PMSM) and principle of field oriented control (FOC), detail modelling of PMSM drive system and simulation results presented in this paper. The PMSM model is based on electronic components rather than mathematical blocks, this enabled us to achieve simulation results more realistic. Moreover all the modules of this simulation, such as inverter and pwm generator are made from scratch instead of using premade Simulink blocks. Simulation was carried on the basis of step change in speed and torque then made performance comparison of several parameters such as abc current, dq current, speed and torque.

Flux switching motor is a type of electric machine that locates both flux source and armature windings on the stator leaving its rotor a simple piece of iron. This machine was developed by combining the toothed stator structure of induction machine and the toothed rotor structure of switched reluctance machine together. Furthermore, it has three types of flux sources which include permanent magnet. Conventionally, the toothed kind of rotor has dominated machines rotor design and has been known for high manufacturing cost and iron loss, resulting to low performance. This calls for worry and the need to overcome it and also reduce the manufacturing cost while securing high torque. This paper presents flux switching permanent magnet motor employing segmented outer rotor for high torque capability. 2D-FEA using JMAG to investigate the motor characteristics in terms of flux linkage, Induce back-emf, cogging torque, maximum average torque and efficiency. Finally, preliminary results and comparison revealed that motors employing segmented rotor are capable of higher torque than conventional toothed rotor.

This paper present with design improvement of 12Slot-14Pole outer rotor field excitation flux switching motor (ORFEFSM) from the initial design by implement Deterministic Optimization Method (DOM) which involve 2-dimensional Finite-Element Analysis (FEA). The design improvement starts with the non-active part, rotor and followed with active part, stator which involve the armature coil slot and field excitation coil (FEC) slot. Since it is one of local optimization method, this method involves more than one cycle of improvement depends on the design structure and slot-pole configuration until achieve optimum performance. However, the initial torque and power output of 12Slot-14Pole is 112.95 Nm and 50.46 kW. The main objective is to improve the structure in order to obtain optimum torque and power output. Besides, it is necessary to reduce flux saturation and optimize the flux flow between the rotor teeth and stator arc width. The target torque and power output performance is expected higher than 210 Nm and 123 kW. With the deterministic optimization method technique, the final torque and power output achived are 221.83 Nm and 189kW. Full Text: PDF DOI: http://dx.doi.org/10.11591/ijpeds.v8.i1.pp239-247

This paper presents a new design and performance of single phase permanent magnet flux-switching machine (PMFSM) for electric bicycle application. 8Slot-12Pole design machine were choose by analyzing the highest power density value. All active parts such as permanent magnet and armature coil are located on the stator, while the rotor part consists of only single piece iron. PMFSM have a great advantage with robust rotor structure that make it much higher power and applicable for EV application compared to SRM and IPMSM. The design, operating principles, characteristics of torque, and power of this new topology are investigated by JMAG-Designer via a 2D-FEA. Size of motor and volume of PM is designed at 75mm and 80g, respectively. Based on the investigation, it can be concluded that the proposed topology of single phase 8Slot 12Pole PMFSM achieved the target of highest performance of power density, approximately at 0.113W/mm3 with reduced permanent magnet and size of design motor. Due to the low torque performance of this initial design, further works is ongoing to improve the torque performance. In future work, outer rotor PMFSM structure design will be presented and compared with the “Deterministic Optimization Method” to improve the initial design.

This paper addresses the irreversible permanent magnet (PM) demagnetization analysis of hybrid excitation flux switching motor (HEFSM) with outer-rotor configuration. PM demagnetization cause the PM strength used in the motor significantly reduces and hence contributes less torque performance. The study is focused on thermal analysis and conducted at various temperature up to as high as 180 degrees Celsius which has a tendency to be demagnetized. Therefore, PM demagnetization is among a critical issue and influences the choice of the applied motor. The analysis is carried out based on finite element method (FEM) and percentage of PM demagnetization is then calculated. Finally, based on simulated and calculated results the final design outer-rotor HEFSM has only 0.85 percent PM demagnetization at very high temperature and obviously the is no PM demagnetization at normal operating conditions.

Permanent magnet flux switching machine (PMFSM) is a joint venture of switch reluctance machine (SRM) and permanent magnet synchronous machine (PMSM). It has become a prominent research topic for various applications because of robust rotor structure, high torque and power densities but few were developed for downhole applications mainly due to harsh environmental conditions. Formerly, most of developed PMFSMs for downhole applications were mainly concentrated on inner-rotor type design, and difficult to find research work on outer-rotor configuration. Therefore, this paper introduces the design and investigation of PMFSM with outer-rotor configuration for downhole application. Primarily, the geometric topology of proposed design is described in detail. Then, the no load and load analysis are implemented in order to investigate the initial performance of the proposed design.