Volume 1 Number 1 June 2015

Performance Evaluation of a Three Phase Nine Level Inverter with Reduced Switch Count

Authors: Balamurugan C.R. ; Natarajan S.P. ; Pavithra S.
Pages: 5-15
This paper presents a three phase nine level cascaded H-bridge (CHB) multilevel inverter with RL load. A sinusoidal and trapezoidal PWM method is used to achieve minimum total harmonics distortion (THD) in the output current of multilevel inverters. The analysis of the output current harmonics is carried out and compared with the seven level conventional cascaded H-bridge inverters. The proposed inverter is verified through simulation and the simulation results are compared with the conventional multilevel inverter. From the result the proposed inverter offers much less total harmonic distortion.

Mechanical Behaviour of Agricultural Residue Reinforced Composites

Authors: B. NagarajaGanesh ; R. Murali Kannan
Pages: 1-4
The increasing awareness and the quest for newer materials have given renewed interest to the development of green composites. This article focuses on the potential use of abundantly available waste agricultural residue for the preparation of composites. The mechanical properties of Rice straw fibers reinforced with Polyester resin, Vinyl ester resin and Isophthalic polyester resin are studied and compared. Hand Layup technique is used to prepare the samples on which flexural and impact studies are made. Samples are made using different volumetric compositions of fiber and resin. The results show that the Vinyl ester resin and Isophthalic resin offer good mechanical properties when compared to the polyester resin. Both these resins show similar behavior with respect fiber loading. The flexural strength decreases with increasing fiber loading for polyester resin and increasing trend is observed for both vinyl ester and isophthalic resin. Impact strength increases for the increase in fiber loading up to a certain limit and then decreases. It can be concluded from this study that the agro-waste materials are attractive reinforcements from the standpoint of their mechanical properties.