Feature based workshop oriented NC planning for asymmetric rotational parts

This thesis describes research which is aimed at devising a framework for a feature based workshop oriented NC planning. The principal objective of this thesis is to utilize a feature based method which can rationalize and enhance part description and in particular part planning and programming on the shop-floor. This work has been done taking into account new developments in the area of shop floor programming. The importance of the techniques and conventions which are addressed in this thesis stems from the recognition that the most effective way to improve and enhance part description is to capture the intent of the engineering drawing by devising a medium in which the recurring patterns of turned components can be modelled for machining. Experimental application software which allows the user to describe the workpiece and subsequently generate the manufacturing code has been realized

An Improved Model Predictive Control Method to Drive an Induction Motor Fed by Three-Level Diode-Clamped Indirect Matrix Converter

In this paper, an improved model predictive control method is proposed to drive an induction motor fed by a three-level matrix converter. The main objective of this paper is to present a novel method to increase the switching frequency at a constant sampling time. Also, it is analytically discussed that increasing the switching frequency not only can decrease the motor current ripples, but it can also significantly reduce its torque ripples. Finally, this study demonstrates that reducing the motor current ripple will improve the quality of the supply current. To be the accurate model and validate the motor drive system, a co-simulation method, which is a combination of FLUX and MATLAB software packages, is employed to find the simulation results. The findings indicate that the proposed method diminishes the THD of the supply current up to 26% approximately. Furthermore, increasing the switching frequency results in the torque ripple reduction by up to 10% almost

Design and Implementation of a single switch high gain boost topology : Structure, Ripple Control and ZCS

The need for high gain DC-DC converters has lately increased in tandem with the utilization of renewable energy supplies. Particularly appealing are high gain converters that do not require the inclusion of extra power switches and/or other passive elements to the system. As a result, this study proposes a non-isolated single switch converter with ultra-high voltage gain (UHG) that is appropriate for most renewable energy conversion systems, like solar installations. With only a single MOSFET working within a suitable duty cycle region, the proposed converter provides significant voltage gain and around 95% efficiency. Moreover, the MOSFET in this UHG converter is turned on in zero current switching (ZCS) mode, resolving the diode recovery issue. The recommended UHG converter’s working modes, steady-state parametric study, circuit variables like voltage stress on switching devices, and converter gain are all thoroughly explained. Comparisons have been done with comparable topologies presented in the literature, and lastly, experimental results depending on 200W (20V input, 320V output voltage) are given to validate the operation of the proposed UHG design.publishedVersionPeer reviewe