Showing 2 results for Dashti
S. M. Mousavi G, A. Dashti,
Volume 4, Issue 4 (12-2014)
Abstract
Induction motors are the most commonly used in the traction industries and electric vehicles, due to their low primary cost, low maintenance costs, and good performance. Speed identification is needed for the induction motor drives. However, using of speed sensors in the induction motor drives is associated with problems such as, extra cost, reduced reliability, added mounting space, etc.. Therefore, many of the recent researches had been dedicated to sensor less induction motor drives. In the induction motor, the rotor speed is estimated using measured stator voltages and currents of the induction motor, as the sensor less drive. The rotor speed for sensor less induction motor drives can be estimated by various techniques, which is designed with respect to required accuracy and sensitivity against induction motor parameter variation. In this paper, comprehensive review of different induction motor speed estimation techniques for traction applications, their special features and advantages is presented.
Dr. Sadjad Pirmohammad, Mr Sobhan Esmaeili Marzdashti, Mrs Elnaz Vosoghifard,
Volume 11, Issue 1 (3-2021)
Abstract
Thin-walled columns are frequently employed in vehicle structures to diminish the damages resulting from vehicle collisions. In this research, the effect of hole shapes and dimensions on crushing behavior of octagonal multi-cell columns subjected to longitudinal loading is studied. Rectangular, hexagonal and elliptical holes are assumed on the octagonal multi-cell columns, and crushing parameters (i.e. specific energy absorption SEA and maximum crushing force Fmax) are then obtained by performing numerical analyses in LS-DYNA. The results demonstrate that creation of holes on column walls improve crushing capability significantly, such that creation of rectangular, hexagonal and elliptical holes on the octagonal multi-cell columns increases the value of SEA by 37%, 42% and 39%, respectively in comparison to the plain octagonal column. On the other hand, presence of holes on the octagonal columns results in reduction of Fmax (as a negative crushing indicator).
