Performance indexes’ evaluation of a novel synchronous reluctance motor with sinusoidal rotor shape

Abstract: This paper presents the evaluation of performance indexes of a novel Synchronous Reluctance Motor (SynRM), which has an axially sinusoidal rotor lamination shape. The stator of a 5.5 kW, 4-pole, 50 Hz conventional three-phase squirrel cage induction motor, with distributed and chorded by one slot, double layer winding, is used for both standard and novel synchronous reluctance motors. Due to the nature of the sinusoidal rotor structure, the 3D Finite Element Analysis (FEA) is utilized to study the electromagnetic parameters of interests. The SynRM with sinusoidal rotor shape results are compared with the standard SynRM without cut-off on the q-axis. The FEA results are validated by means of practical measurements. From both FEA and measured results, it is evident that the novel SynRM enhances the performance indexes of interests such as torque density, torque ripple factor and efficiency

Novel synchronous reluctance motor with sinusoidal rotor lamination shape for less torque ripple contents

Abstract: This paper presents the analysis of a novel Synchronous Reluctance Motor (SynRM), which has an axially sinusoidal rotor lamination shape. The sinusoidal lamination shape is used to vary magnetic flux in the q-axis direction. Therefore, cancelling some torque harmonics produced by stator slotting effects and rotor anisotropy, while maintaining the average torque. The stator of a 5.5 kW, 4-pole, 50 Hz conventional three-phase squirrel cage induction motor, with distributed and chorded by one slot, double layer winding, is used for both standard and novel motors. The Finite Element Analysis (FEM) is used to study the electromagnetic parameters of interests. The FEA results are validated by means of practical measurements. The results obtained from both FEA and practical measurements evidenced that the novel SynRM dropped tremendously the torque ripple contents while still maintained the average torque. The drop in torque ripple contents is mainly due to mitigation of the most dominant torque harmonics caused by stator slotting and rotor anisotropy

THE MAIN RESULTS OF ARCHAEOLOGICAL RESEARCH AT REȘCA-ROMULA (1869-2019) AND CONSIDERATIONS ON THE GEOPHYSICAL APPROACH – PART I

Book Chapter in INSIGHTS OF GEOSCIENCES FOR NATURAL HAZARDS AND CULTURAL HERITAGE, Editor: Florina CHITE

Technological Growth and Asset Pricing

In this paper we study the implications of general-purpose technological growth for asset prices. The model features two types of shocks: "small", frequent, and disembodied shocks to productivity and "large" technological innovations, which are embodied into new vintages of the capital stock. While the former affect the economy on impact, the latter affect the economy with lags, since firms need to first adopt the new technologies through investment. The process of adoption leads to cycles in asset valuations and risk premia as firms convert the growth options associated with the new technologies into assets in place. This process can help provide a unified, investment-based view of some well documented phenomena such as the asset-valuation patterns around major technological innovations, the countercyclical behavior of returns, the lead-lag relationship between the stock market and output, and the increasing patterns of consumption-return correlations over longer horizons.

A Study of the Interactions Between the Double Bonds in Unsaturated Ketones

The interactions between C=C and C=O double bonds in several unsaturated ketones have been studied by comparing MIND0/2 caloulations wiith ionisation potentials determined by photoelectron spectroscopy (PES). With one exception (norbornadienone) the direct through-space interactions in conjugated .ketones appear to be negligible, the double bonds couple hyperoonjugatively via the intervening a bonds. This kind of approach should prove useful for studying other long range interactions

Investigation into effects of a novel rotor cut-off design for synchronous reluctance machines

Abstract: This paper presents an investigation into the effects of a novel rotor cut-off design on the performance of a synchronous reluctance machine. The rotor design consists of a sinusoidal lamination shape in the axial direction thereby varying the magnetic flux in the q-axis direction and reducing torque harmonics due to slotting effects. The presented study uses single-factor experimental design, with Analysis of Variance (ANOVA), and Finite Element Analysis (FEA) to quantitatively and qualitatively assess the effects of the rotor cut-off on the torque, torque ripple, saliency, power factor and efficiency of the machine. Results of the investigation indicate that although variation in the rotor cut-off design significantly reduces the torque ripple, the effects on the average output torque, saliency, power factor of the machine are relatively insignificant. Index Terms—Synchronous Reluctance Machine; Rotor Design; ANOVA; FEA

Modelling and analysis of a radio frequency dielectric heating for defatted soy flour

Abstract: In this paper a Radio Frequency (RF) method for drying defeated soy flower is developed using a class E amplifier. The raw and uncooked soy flour contains a few undesirable inherent soybean enzymes. Minimizing the content and effect of these enzymes usually is done through “drying/heating” methods. The method used in this study is “RF dielectric heating”. Modelling, simulation and implementation results complete the paper