15,681 research outputs found
Modelling approaches for DC-DC converters with switched capacitors
No full textIn this paper we review relevant problems in the modelling of DC-DC converters with switched capacitors. We study several approaches that overcome the exposed modelling difficulties, addressing ideal and nonideal cases and using dynamic equations that are valid in a large signal domain
Arthur Andrew Lopez
No full textArthur Andrew Lopez was born and raised in Chicago, Ilinois. He graduated from Proviso West High School (Northlake, Illinois) in 1971. Lopez put himself through three years of college at Triton Junior College (Illinois) before transferring to Indiana University, where he received his B.S. degree in education in 1978. Additionally he graduated from the Indiana Law Enforcement Academy and worked as a police officer for Indiana University. While at IU, Lopez helped establish the first Latino Affairs Committee within the University’s resident halls. Lopez enrolled at the Indiana University School of Law in 1980 and received his JD in 1983.
Today, Lopez is a Clinical Professor of Business Law and Ethics at the Indiana University Kelly School of Business. Prior to returning to IU, Lopez served more than 20 years as an attorney for the Federal government in Washington, DC. Among the positions he held were, Associate General Counsel for the U.S. Office of Government Ethics, Director of the Office of Civil Rights for the Federal Transit Administration, attorney for the Office of Chief Counsel, and ethics attorney in the Office of White House Counsel. Prior to his time in Washington, Lopez served as an in-house counsel to both Navistar International and Toyota Motor Sales.
Lopez is the founder and president of Nadar Por Vida, a non-for-profit corporation committed to providing at-risk, minority, and low-income children an introduction to the world of competitive swimming. Founder of the law school’s Latino Alumni Association, Lopez has be honored with many awards, including the Indiana University Latino Alumni Association’s Latino Alumni Award (2007) and Maurer School of Law’s Distinguished Service Award (2009). Lopez served on the law school\u27s Alumni Board since 2011.https://www.repository.law.indiana.edu/notablealumni/1173/thumbnail.jp
Arthur Andrew Lopez
No full textArthur Andrew Lopez was born and raised in Chicago, Ilinois. He graduated from Proviso West High School (Northlake, Illinois) in 1971. Lopez put himself through three years of college at Triton Junior College (Illinois) before transferring to Indiana University, where he received his B.S. degree in education in 1978. Additionally he graduated from the Indiana Law Enforcement Academy and worked as a police officer for Indiana University. While at IU, Lopez helped establish the first Latino Affairs Committee within the University’s resident halls. Lopez enrolled at the Indiana University School of Law in 1980 and received his JD in 1983.
Today, Lopez is a Clinical Professor of Business Law and Ethics at the Indiana University Kelly School of Business. Prior to returning to IU, Lopez served more than 20 years as an attorney for the Federal government in Washington, DC. Among the positions he held were, Associate General Counsel for the U.S. Office of Government Ethics, Director of the Office of Civil Rights for the Federal Transit Administration, attorney for the Office of Chief Counsel, and ethics attorney in the Office of White House Counsel. Prior to his time in Washington, Lopez served as an in-house counsel to both Navistar International and Toyota Motor Sales.
Lopez is the founder and president of Nadar Por Vida, a non-for-profit corporation committed to providing at-risk, minority, and low-income children an introduction to the world of competitive swimming. Founder of the law school’s Latino Alumni Association, Lopez has be honored with many awards, including the Indiana University Latino Alumni Association’s Latino Alumni Award (2007) and Maurer School of Law’s Distinguished Service Award (2009). Lopez served on the law school\u27s Alumni Board since 2011.https://www.repository.law.indiana.edu/notablealumni/1173/thumbnail.jp
Common Mode Currents in DC Power Routers
No full textThe grid reinforcement and energy redirection needs have led to the emergence of Back-To-Back Voltage Source Converter (BTB-VSC) based dc power routers. This paper investigates the low frequency Common Mode Currents (CMCs) that arise in the system if the employed BTB-VSCs have an un-isolated ac path connected in parallel to their output ports. Simulation results are presented to show a sensitivity analysis of lower order harmonics in CMC with respect to the operating active and reactive power of the dc router, dc link voltage, link resistance, modulation method and pole capacitance. Experimental results are shared to show existance of lower order CMC in 3-wire ac link operating in parallel with the dc power router and these are mitigated using zero sequence controller
Modeling, Control, and Operation of an M-DAB DC-DC Converter for Interconnection of HVDC Grids
No full textFuture high-voltage direct-current (HVDC) networks based on voltage source converters (VSCs) will have different structures (asymmetric monopolar, bipolar, or symmetric monopolar), voltage levels, control, and protection schemes. Therefore, dc-dc converters are needed to interconnect those VSC-HVDC grids and several technical issues on their control and operational systems must be adequately addressed. A dc-dc converter based on a modular-dual active bridge (M-DAB) converter is suggested to reach a desirable interconnection of the HVDC grids and regulate power flow (PF) between them. A dynamic averaged model is proposed for the M-DAB converter and its stability is analyzed using the Lyapunov function. Moreover, a new local controller based on nonlinear control theory is proposed for the M-DAB. The new M-DAB local controller is integrated with the energy management system (EMS), by updating the PF equations, to create a complete control structure. Considering the CIGRE DCS3 HVDC test system and the studied M-DAB, static, dynamic simulation, and experimental studies are conducted and the dc-dc converter and the performance of the designed controllers and the EMS are examined and validated.Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Intelligent Electrical Power Grid
indigo-dc/udocker: udocker 1.1.2
No full textudocker v1.1.2 see the changelog and the documentation for further information.
changelog: https://github.com/indigo-dc/udocker/blob/master/changelog
documentation: https://github.com/indigo-dc/udocker/blob/master/SUMMARY.m
indigo-dc/udocker: udocker 1.3.4
No full textudocker v1.3.4 see the changelog and the documentation for further information.
Changelog: https://github.com/indigo-dc/udocker/blob/master/CHANGELOG.md
Documentation: https://indigo-dc.github.io/udocker/
udocker release for Python 2.7 and >= 3.6
Follow these steps to install and run udocker:
wget https://github.com/indigo-dc/udocker/releases/download/v1.3.4/udocker-1.3.4.tar.gz
tar zxvf udocker-1.3.4.tar.gz
export PATH=`pwd`/udocker:$PATH
Test with:
udocker --help
udocker instal
Restructuring the existing medium voltage distribution grids using DC systems
No full textGreen Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.DC systems, Energy conversion & Storag
Cold cracking in DC-cast high strength aluminum alloy ingots: An intrinsic problem intensified by casting process parameters
No full textFor almost half a century the catastrophic failure of direct chill (DC) cast high strength aluminum alloys has been challenging the production of sound ingots. To overcome this problem, a criterion is required that can assist the researchers in predicting the critical conditions which facilitate the catastrophic failure of the ingots. This could be achieved at first glance by application of computer simulations to assess the level and distribution of residual thermal stresses. However, the simulation results are only able to show the critical locations and conditions where and when high stresses may appear in the ingots. The prediction of critical void/crack size requires simultaneous application of fracture mechanics. In this paper, we present the thermo-mechanical simulation results that indicate the critical crack size distribution in several DC-cast billets cast at various casting conditions. The simulation results were validated upon experimental DC-casting trials and revealed that the existence of voids/cracks with a considerable size is required for cold cracking to occur.Materials Science & EngineeringMechanical, Maritime and Materials Engineerin
A Dynamically Reconfigurable Recursive Switched-Capacitor DC-DC Converter with Adaptive Load Ability Enhancement
No full textMultiple voltage conversion ratio (VCR) recursive switched-capacitor (SC) dc-dc converters, based on several basic 2:1 converters, are widely used for on-chip power supplies due to their flexible VCRs for higher energy efficiency. However, conventional multiple VCR SC converters usually have one or more 2:1 converters unused for some VCRs, which results in lower power density and chip area wastage. This article presents a new recursive dc-dc converter system, which can dynamically reconfigure the connection of all on-chip 2:1 converter cells so that the unused converters in the conventional designs can be reused in this new architecture for increasing the load-driving capacity, power density, and power efficiency. To validate the design, a 4-bit-input 15-ratio system was designed and fabricated in a 180-nm BCD process, which can support a maximum load current of \text{0.71}\,\text{mA} and achieves a peak power efficiency of 93.1% with 105.3\,\mu \text{A/mm} {2} chip power density from a 2-V input power supply. The measurement results show that the load-driving capacity can become 6.826×, 2.236×, and 2.175× larger than the conventional topology when the VCR is 1/2, 1/4, and 3/4, respectively. In addition, the power efficiency under these specific VCRs can also be improved considerably.Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Electronic Instrumentatio
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