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The inclusion of a high energy density permanent magnet into magnetic gear improves the machine's torque density. However, it also contributes to eddy current loss, especially in a high-speed application such in electric vehicle. In this paper, the losses from eddy current and iron loss are investigated on concentric magnetic gear (CMG). Torque multiplier CMG is designed with 8/3 gear ratio for this study. Iron loss and eddy current loss are compared and discussed. Based on this study, eddy current loss contributes to almost 96% of the total loss. This finding is hoped to direct the researcher to focus more on reducing loss associated with eddy current loss.

<p>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.</p>

Most of commercial Hybrid Electric Vehicle (HEV)used single motor and transmission gears coupled to the wheels. This system leads to the transmission losses and reduce the efficiency and reliability of the motor. Therefore, in-wheel direct drive mechanism is introduced to overcome this problem. In-wheel direct drive eliminates the mechanical transmission, differential gears and drive belts. Thus, in-wheel direct drive provides quick torque response, higher efficiency, weight reduction, and increased vehicle space. As one of alternative, a new design of hybrid excitation flux switching motor (ORHEFSM) for in-wheel drive EV is proposed. First coil arrangement tests are analyzed to confirm the phase of each armature coil phase. Then, flux comparison of PM with DC FEC, flux linkage at various FEC current densities, cogging torque, induced voltage/ back EMF of PM with DC FEC, torque and power versus FEC current density at various armature coil current densities are also analyzed. The generated results show that the appropriate combination of stator slot-rotor pole configurations are 8S-4P and 8S-8P respectively, which initially provide highest torque performance and power density. By further design modification and optimization it is expected that the low cost motor will successfully achieved the target performances.