AUTOR DO BLOG ENG.ARMANDO CAVERO MIRANDA SÃO PAULO BRASIL

"OBRIGADO DEUS PELA VIDA,PELA MINHA FAMILIA,PELO TRABALHO,PELO PÃO DE CADA DIA,PROTEGENOS DO MAL"

"OBRIGADO DEUS PELA VIDA,PELA MINHA FAMILIA,PELO TRABALHO,PELO PÃO DE CADA DIA,PROTEGENOS  DO MAL"

“SE SEUS PROJETOS FOREM PARA UM ANO,SEMEIE O GRÂO.SE FOREM PARA DEZ ANOS,PLANTE UMA ÁRVORE.SE FOREM PARA CEM ANOS,EDUQUE O POVO.”

“Sixty years ago I knew everything; now I know nothing; education is a progressive discovery of our own ignorance. Will Durant”

quinta-feira, 15 de janeiro de 2015

A Study on the Surge Protection of Shipboard Electrical and Electronic Devices Electrical and Electronic Engineering,BY SUNG-JU PARK Korea Maritime University,





A Study on the Surge Protection of Shipboard Electrical and Electronic Devices

ABSTRACT

The surge on the shipboard is generated by an insulation breakdown, a short circuit and a switch operation, and is propagated via power, signal and communication, control cables and hull. The surge may lead to serious damage to electrical and electronic devices on shipboard. With this background, this thesis analyzed the power system of ships and carried out an experimental study on the surge protective method and device. Parallel type surge protective devices(SPD) with the 220[V] and the 440[V] rated voltage, and a series type SPD with the 220[V] rated voltage for electrical sensitive devices are designed and fabricated. A surge generator specified in IEC 61000-4-5 which can produce 8/20[us] current up to 15[kA] was fabricated to evaluate the proposed SPDs. The performance of the SPDs were evaluated by an un-powered test which applies the 8/20[us] surge current up to 10[kA] and by a powered test which superimpose a surge on the 220[V] and 60[Hz]. The maximum residual voltage of the parallel type SPD for the un-powered and the powered test were 1290[V] and 891[V], and of the series type SPD were 875[V] and 656[V], respectively. The experimental results showed that the series type SPD is more effective to protect electrical sensitive devices such as signal and communication devices since the series type SPD suppresses surge lower residual voltage than the parallel one. Also, insulation voltage of the shipboard electrical and electronic devices were compared to the residual voltage of the SPDs. The residual voltages of the SPDs were lower than the demanded insulation voltage level for the mains of the 220[V] and the 440[V]. Therefore, it was confirmed that the proposed SPDs have a sufficient performance to protect the shipboard electrical and electronic devices from surge voltages.

terça-feira, 13 de janeiro de 2015

Gonzalo Villarán - UTEC Ventures- Universidad de Ingeniería y Tecnología (UTEC).-LIMA-PERU



 Gonzalo Villarán gvillaran@utec.edu.pe , Director de UTEC Ventures, nos presenta la aceleradora de start-ups (nuevas empresas de base tecnológica) de la Universidad de Ingeniería y Tecnología (UTEC). La presentación la organizó el Comité de Innovación Tecnológica Industrial (CINTECIN) en el Ministerio de la Producción (PRODUCE). Lima, 19 de agosto de 2014.
LINK1
http://cienciatecnologiainnovacion.blogspot.com.br/
LINK2
http://utecventures.com/

segunda-feira, 12 de janeiro de 2015

Realizzazione di un generatore di impulsi per la caratterizzazione di dispositivi di potenza DIPARTIMENTO DI INGEGNERIA “ENZO FERRARI” CORSO DI LAUREA MAGISTRALE IN INGEGNERIA ELETTRONICA






UNIVERSITA’ DI MODENA E REGGIO EMILIA
DIPARTIMENTO DI INGEGNERIA “ENZO FERRARI”
CORSO DI LAUREA MAGISTRALE IN INGEGNERIA ELETTRONICA
Realizzazione di un generatore di impulsi per la caratterizzazione di
dispositivi di potenza

Abstract
Realization of a printed circuit pulse generator very fast for the characterization of high-power devices using double pulse measurement, from which to derive information about the device tested as diverse as its thermal activity, problems with charge trapping and overall performance of the device. Perform the measurements on the device by the pulser achieved with the use of labview software, with which to synchronize the instruments used and the final automated data collection for its characterization

Introduzione: L’obiettivo di questa tesi è la realizzazione di un generatore di impulsi con il quale eseguire la caratterizzazione di dispositivi ad elevata potenza, mediante un particolare metodo di misura denominato “double pulse measurement”. Per la misura sarà realizzata un interfaccia mediante l’utilizzo del software Labview, con la quale eseguire in modo completamente automatizzato la caratterizzazione del dispositivo semplicemente impostando i parametri di interesse. Vediamo in maggior dettaglio come sarà articolata la tesi.
LINK ORIGINAL
https://morethesis.unimore.it/theses/available/etd-03242014-113750/unrestricted/TESI_DI_LAUREA_MAGISTRALE.pdf

quinta-feira, 8 de janeiro de 2015

Design of High-Current Inverter-type Rectifier for Electrolytic disinfection of Seawater Won Woo Cho Department of Electrical Engineering, The Graduate School, Pukyong NatIonal University












Design of High-Current Inverter-type Rectifier for Electrolytic disinfection of Seawater
Won Woo Cho
 Department of Electrical Engineering, The Graduate School, Pukyong NatIonal University
 Abstract

As the import and export cargos across the world increase with global trade environments, the ecocide caused by a lot of small marine organisms in the ship's ballast water is a big issue. To reduce the problem of ecocide, the BWTS (Ballast water treatment system) should be installed in ship. The implementation of the BWTS thus needs low-voltage high-current rectifier for electrolytic disinfection. So this paper proposes a suitable high-current inverter-type rectifier for electrolytic disinfection of seawater and analyzes its output characteristics. It also suggests the practical design guidelines for the proposed rectifier in terms of power circuit and controller designs.

segunda-feira, 5 de janeiro de 2015

Consideration on The Improvement of Input Currents for Variable Frequency Drive by Reactors Author Kim Hee Moon Department of Ocean Systems Engineering Graduate School of Korea Maritime University




Consideration on The Improvement of Input Currents for Variable Frequency Drive by Reactors
Author  Kim Hee Moon
Department of Ocean Systems Engineering Graduate School of Korea Maritime University
Abstract
AC line reactors and dc link reactors are widely used in variable frequency drives(VFDs) to improve the drive performance such as reducing input current harmonics,elevating input power factor,and protecting the drives from surges,etc.The effectiveness of both types of reactors in reducing input harmonics is affected by the loading of the drives and the system source impedance.In this paper,a simulation is performed to investigate of such factors.The rules to evaluate the needs and effectiveness using ac line or dc link reactors are proposed for practical applications

LOWPASS BROADBAND HARMONIC FILTER DESIGN A THESIS SUBMITTED TO THE GRADUATE SCHOOL OF NATURAL AND APPLIED SCIENCES OF MIDDLE EAST TECHNICAL UNIVERSITY BY HAZEM ZUBI






LOWPASS BROADBAND HARMONIC FILTER DESIGN
A THESIS SUBMITTED TO THE GRADUATE SCHOOL OF NATURAL AND APPLIED SCIENCES OF MIDDLE EAST TECHNICAL UNIVERSITY BY HAZEM ZUBI

IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE IN ELECTRICAL AND ELECTRONICS ENGINEERING

 ABSTRACT
Department of Electrical and Electronics Engineering Supervisor: Asst. Prof. Dr. Ahmet M. Hava September 2005, 192 pages In this thesis an analytical design method of the improved broadband passive harmonic filter (IBF) for three phase diode rectifier front-end type adjustable speed drives is presented. The method is based on frequency domain modeling of the rectifier and filter. The success of the method involves accurate representation of the load harmonics. With the harmonics well defined, the harmonic and fundamental frequency equivalent circuits are utilized to analytically calculate the voltages/currents. Thus, the size and the performance of the filter can be optimized. The analytical method is verified via computer simulations and laboratory experiments. Also a performance comparison of various passive harmonic filters for three-phase diode rectifier front-end type adjustable speed drives is provided. The comparison involves the input current total harmonic distortion, input power factor, rectifier voltage regulation, energy efficiency, size, and cost. The parallel/series harmonic resonance problem related issues are addressed and unbalanced operation performance investigated. The comparison is based on analysis and computer simulations and the results are validated by laboratory experiments
LINK FULL THESIS
http://www.eee.metu.edu.tr/~hava/hazem-thesis-LOWPASS%20BROADBAND%20HARMONIC%20FILTER%20DESIGN.pdf

domingo, 4 de janeiro de 2015

The Importance of Acceptable Electrical Power Quality to the Drilling Industry Worldwide Ian C Evans, Harmonic Solutions (Oil & Gas), Ras Al Khaimah, United Arab Emirates








The Importance of Acceptable Electrical Power Quality to the Drilling
Industry Worldwide
Ian C Evans, Harmonic Solutions (Oil & Gas), Ras Al Khaimah, United Arab Emirates

Copyright 2013, SPE/IADC Middle East Drilling Technology Conference and Exhibition
This paper was prepared for presentation at the SPE/IADC Middle East Drilling Technology Conference and Exhibition held in Dubai, UAE, 7–9 October 2013.

Abstract
Electrical power quality is routinely taken for granted by oil and drilling industries worldwide despite the fact that the quality of electrical power is fundamental to the safety and operational integrity of drilling rigs and oil production platforms worldwide, without exception. US$100m’s are lost each year, direct and indirectly, due to poor quality of power. Currently some offshore safety authorities are considering the imposition of strict limits on harmonic voltage distortion in their jurisdiction. Harmonic voltage distortion may become a regulatory issue in the future. This paper examines the salient harmonic and power quality issues onboard drilling rigs with full SCR drilling packages, as well the more recent hybrid (mixed SCR and VFD drives) and full VFD (variable frequency drive) drilling packages. With SCR drives the main problems are harmonic voltage distortion, line notching and voltage spikes which destroys capacitors inside equipment. Low generator power factor is also often an operational problem. For VFDs, harmonic voltage distortion is also a problem but increasingly so is excessive common mode voltage caused by VFD operation which disrupts susceptible electronic equipment. The paper will offer advice on proven solutions for common power quality problems and introduce a remote/local power quality monitoring system which can be easily retrofitted to existing rigs and platforms.
LINK ORIGINAL
http://www.harmonicsolutions-oilandgas.com/wp-content/uploads/2014/08/SPE_IADC_166773-MS_The-Importance-of-Acceptable-Electrical-Power-Quality-to-the-Drilling-Industry-Worldwide_17th-August-2013_XXXX.pdf

The Price of Poor Power Quality Ian C Evans, Harmonic Solutions Co. UK and Michael J Richards, Algozen Corporation, Canada





The Price of Poor Power Quality

Ian C Evans, Harmonic Solutions Co. UK and Michael J Richards, Algozen Corporation, Canada
Abstract 
Electric drives, both DC drives (often called “SCR drives” in the industry) and AC variable frequency drives (VFDs), are commonplace on drilling rigs and offshore installations. Their operation can significantly degrade the quality of electric power, resulting in loss of operational capability, equipment failure with subsequent down-time in addition to presenting safety concerns. Marine classification bodies have rules to limit harmonic voltage distortion but these are rarely policed. The quality and security of electric power are absolutely crucial to the operational integrity of any drilling rig or offshore installation, irrespective of type or class. Any failure or malfunction of equipment due to poor power quality can result in severe or disastrous consequences. This paper looks at the main problems associated with poor power quality, including excessive harmonic voltage distortion, line notching (SCR drives) and voltage spikes attributed to SCR drives; these are all traditional ‘harmonics problems’. However, the introduction of large VFDs has resulted in significant increases in ‘common mode voltage’ problems which can be extremely problematic; even to the point where rigs are being taken off-hire due to major equipment being deemed ‘dangerous’. On another rig, the gas detection system failed when the top drive VFD was running due to this problem. This paper will provide a practical understanding of each problem and how they can be resolved. The paper also introduces an inexpensive, yet powerful, remote power quality monitoring system which can be easily retrofitted to monitor all aspects of land-rig and offshore rig power quality, including waveforms and harmonic spectrums. The data is available locally with the capability to transmit the information via the internet to anywhere in the World.

LINK FULL PAPER ORIGINAL
https://www.google.com.br/url?sa=t&rct=j&q=&esrc=s&source=web&cd=3&cad=rja&uact=8&ved=0CC4QFjAC&url=http%3A%2F%2Fwww.aade.org%2Fapp%2Fdownload%2F6857647004%2FAADE-11-NTCE-07.pdf&ei=QnSpVKLzJdOTNtLxgogH&usg=AFQjCNHm05m6r6W9vVUSJZlCLLT4ATHEkQ&sig2=DuFagJEuZCRiGxGxUUqrig

LINK ALTERNATIVE
https://copy.com/fyS9nLkVUXPffmPB


Harmonics Reduction Techniques in Renewable Energy Interfacing Gonverters Ali M. Eltamaly, Ph.D King Saud University Saudi Arabia





INTRODUCTION
 In the recent years there has been growing interest in renewable energy generation along with growing demands for development of a suitable interface system. Low harmonics in line current of the converters used in the utility interface.
  Controlled and uncontrolled converters are used widely in the utility interface of renewable energy systems to reduce cost, harmonic contents in line currents. A detailed third harmonic current injection technique reduce the harmonic contents in line currents of controlled and uncontrolled converters that used in renewable energ'y applications. The approach is based on circulaling third harmonic current from DC link current to line currents of controlled and uncontrolled converters to reduce its THD. A new injected current shape is computed from analysis to achieve sinusoidal utility line currents. A controllable single switch boost converter conrrccted in shunt is employed to circulate the new injected current shape. A method to implement the proposed approach under varying load condition is shown. Analysis,d esign,l imitations,s imulationa nd experimentarl esult are presented. In modern Power electronics converters, three-phase controlled converter is commonly used.

LINK FULL PAPER
http://faculty.ksu.edu.sa/eltamaly/Documents/[3].pdf

LINK ALTERNATIVE
https://copy.com/IApswwIOUqPR0xNt


sábado, 3 de janeiro de 2015

Study on the component analysis of harmonic current to specify the cause of fault in electrical power line Author Park, Chan Heon



 ABSTRACT

Development of power semiconductors has promoted to the advancement of large static power converters. Due to use of these converters, the power quality has become a very important and highly controversial issue in today's industrial environments. Converters of the supplied 60Hz ac to dc or to variable frequency ac power offers more precise speed control and increased efficiencies for many industrial processes. These advantages have accelerated wide spread usage of static power converters. However, these advantages cause disadvantages of increased sensitivity to both the quality of power supplied by the utility and the quality of the power inside the industrial facility. With these trends of industrial environments, both electric utilities and end users of electric power are increasingly concerned about quality of electric power. And the harmonic problem becomes one of the most important issues on the power quality problems. Therefore, this thesis aimed to represents theoretical study, occurence examples, and countermeasure of harmonics. Therefore, in this thesis also introduces terms and generation of harmonics characters based on different loads and clarified the areas of harmonic problems on the industrial facilities. In end of this thesis, it has been discussed for controlling of harmonics. Chapter 3 provided the guidelines for the harmonics level referenced from Korea, Japan, and IEEE std 519-1992. In chapter 4, this thesis presents the results of example study as regards a fault owing to OCGR(Over Current Ground Relay) and another fault owing to N phase line in main transformer of substation. Chapter 5 illustrates the delivered reference for power filters, and suggest real time PQM(Power Quality Management) system to diagnosis harmonics. This paper wishes to express that these study results may contribute to localization of power filters and to resolution of harmonic problems.