Effect of different core materials in very low voltage induction motors for electric vehicle

The use of squirrel cage induction motor for electric vehicle (EV) has been increasingly popular than permanent magnet and brushless motors due to their independence on rare materials. However, its performance is significantly affected by the core materials. In this research, induction motors performance with various core materials (M19_24G, Arnon7, and nickel steel carpenter) are studied in very low voltage. Three phases, 50 Hz, 5 HP, 48 V induction motor were used as the propulsion force testbed applied for a golf cart EV. The aims are to identify loss distribution according to core materials and compare power density and cost. The design process firstly determines the motor specifications, then calculates the dimensions, windings, stator, and rotor slots using MATLAB. The parameters obtained are used as inputs to ANSYS Maxwell to calculate induction motor performance. Finally, the design simulations are carried out on RMxprt and 2D transient software to determine the loss characteristics of core materials. It is found that the stator winding dominates the loss distribution. Winding losses have accounted for 52-55 % of the total loss, followed by rotor winding losses around 25-27 % and losses in the core around 1-7 %. Based on the three materials tested, nickel steel carpenter and M19_24G attain the highest efficiency with 83.27 % and 83.10 %, respectively, while M19_24G and Arnon7 possess the highest power density with 0.37 kW/kg and 0.38 kW/kg whereas, in term of production cost, the Arnon7 is the lowest.

MICROENCAPSULATION AND ITS UTILIZATION IN THE SECTOR OF HORTICULTURE : A REVIEW

Microencapsulation today has evolved as a trustworthy tool in providing endurance to majority of the biologically active compounds which in general are not so stable and tends to degenerate very easily. In the field of horticulture, the horticultural commodities are stacked with such important active compounds. These compounds help in providing an advantageous output against various types of diseases and health related issues and ailments. But as mentioned majority of these important substances are not very rigid and extremely susceptible to changes in the environment, which may be physical, chemical or biological type. Therefore microencapsulation comes out as an important an protective tool where these targeted compounds called as the core materials are being covered or wrapped by the encapsulation process through outer coating called as the wall material and final product called as the microcapsules are delivered which have an increased availability and high effectiveness of the core materials inside. Therefore, the present paper is aimed in discussing about the process of microencapsulation in brief and to through a light toward some of the works of microencapsulation which has been successfully carried out in the discipline of horticulture.

Effects of core grain orientation on the mechanical properties of wood sandwich composite

Utilization of sandwich composite during recent year has been driven by the fact that compositematerial has ultimately high strength and stiffness by weight than any other materials. The skins ofsandwich composites technically bear most of the applied loads, however, the core materials alsoplay an important role as it functions in providing continuous support to resist the shear stress.Hence, proper selection of core materials is required to establish a sturdy sandwich compositestructure. This paper presents an experimental investigation on the sandwich structure consists offibreglass/epoxy face skins and a mahang wood core. Sandwich composite with core grain orientedin parallel and perpendicular to the flat plane direction were tested for mechanical performance intension, compression and flexure. The results indicate that sandwich composite with grain orientedin parallel direction performed better in tensile properties with strength of 201.98 MPa whereassandwich composite with perpendicular core grain produced a higher value of compressionproperties with strength of 70.11 MPa. However, no significant effect of grain orientation wasobserved in flexural strength. The strength of sandwich composite is dependent on the grainalignment of the wood core as it functions exclusively as mechanical supporting cells to supportthe wood structure.