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

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