Analysis of Field Orientation Control of Current Source Inverter Drive Induction Motor Systems

The field orientation control of current source inverter (CSI) drive induction motor (IM) systems has been known to give an induction motor dc motorlike characteristics. As a result of an analysis, the characteristic of these systems does not necessarily coincide with that of dc motor systems, especially with light loads. The result of the analysis is verified by experiments.     

Molecular dynamics in semiconductor physics

Molecular dynamics, which is a powerful method for studying both structural and dynamic properties of condensed matter, is employed as a “microscope for the motion of atoms”. Information about the motion of individual atoms that is difficult to obtain experimentally can be obtained using this method. Parallel computers with tera-flop speed and tera-byte memory will make it possible to perform hundreds of million particle simulations using empirical potential. Moreover, the macroscopic phenomena analyzed by continuum theory can be obtained by coarse-graining the atomic-level information provided by this approach. When considering the problem of data analysis, examples in semiconductor physics such as the implantation process are provided.     

Reliability of Induction Machines for High Performance Based on Parameter Characteristics

Nowadays induction machines of enclosed slot rotor structure are widely utilised and are also being applied to ac servo drive for high performance. However, since in this types of machines local magnetic saturation is found at relatively small flux levels due to its rotor structure, the parameters have large discrepancies in their values depending on the identification methods. Moreover, stator current is much more distorted immediately after a stepwise change in the stator voltage. This means that distortion of the flux is enhanced even if stator current is controlled sinusoidally.