This paper presents some implementation details of a threephase to three-phase matrix converter prototype. The bidirectional semiconductor switches were built using discrete IGBTs and fast diodes. Design aspects such as protection against overvoltage and short-circuit, commutation process Artigo submetido em 23/04/2010 (Id.: 1132) Revisado em 18/09/2010, 15/07/2011, 30/08/2011 Aceito sob recome...

Multilevel converters are powerful converters in the medium-voltage high-power range. Inside this family of converters, the three-level neutral point clamped converter has its own importance. The main control methods associated with this converter are the carrier-based PWM with added DC components and the space vector PWM. Two of the most important features of the NPC converter are the neutral ...

Matrix converter is a single-stage converter which directly connects a three-phase voltage source to a three-phase load without dc-link components. Therefore, any harmonic distortion and imbalance in input voltage directly reflect to the output of the converter. Recently, many researchers have made an effort to cope with this problem. In this paper, under distorted input voltage conditions, beh...

Pulse width modulation strategies have been developed for indirect matrix converters (IMCs) in order to improve their performance. In indirect matrix converters, the LC input filter is used to remove input current harmonics and electromagnetic interference problems. Unfortunately, due to the existence of the input filter, the input power factor is diminished, especially during operation at low ...

In this paper, a new step-up/step-down AC-AC converter is designed by switched capacitor (SC) techniques. The main features of the proposed SC AC-AC converter are the symmetrical converter topology and the absence of magnetic elements. Owing to the symmetrical converter topology, the number of capacitors in the proposed AC-AC converter is fewer than that in the conventional SC AC-AC converter. ...

the share of dc-based renewable energy resources (rers) and electricity storage systems are increasing due to developments of smart grid technologies. moreover, the share of dc-based load has rapid growth due to significant developments of power electronic technologies. therefore, a more flexible power system is required for efficient integration of emerging loads and generators. in this paper,...

this study demonstrates the use of a selective and sensitive voltammetric sensor for determination of acetaminophen (ac). this was  performed by modifying a glassy carbon electrode with composite film of poly(4-vinylpyridine) and graphene sheet (p4vp/gr-gce). the redox peak currents of ac increased significantly at p4vp/gr-gce. the result was achieved by the synergistic effect of combined elect...

development of yeast artificial chromosome (y ac) vectors, molecular cloning of large segments of chromosomal dna, and their propagation in yeast cells has become feasible. overlapping y ac provides a route to the development of physical maps of entire mammalian chromosomes. a rapid method was developed to isolate and sequence termini of y ac inserts quickly. the y ac clone is digested with a r...