Uninterruptible Power Networks AB

Publications Archive
This is the archive where you can find publications with UPN connection. The archive lists articles both in English and in Swedish. If an article is in Swedish it may be that there also exists an English version, or an English abstract. Please get in contact.
Publikationsarkiv
I detta arkiv återfinnes publikationer med UPN-anknytning.
*Emergency Power Island in Gnesta community / Reservkraftsö Gnesta:*
Kort presentation / Condensed presentation - emergency power system for a community with 10 000+ inhabitants. (pdf-file) Authors: John Åkerlund, C. Boije af Gennäs, Bo Lindemark 2008. Presentation for Swedish Energy Authority. In Swedish only.
Complete report including implementation / Komplett rapport - technical description of project, implementation and prerequisites. (Zip-file, right click and download) Authors: John Åkerlund, C. Boije af Gennäs, Bo Lindemark 2008. UPN/Gnesta kommun/Swedish Energy Authority. In Swedish only.

*Primary Energy - Solar and Wind Power / Primärenergi - Sol- och vindkraft :*
Ericsson Sunwind - power supply system with sun and wind as combined energy sources. Author: John Åkerlund. Ericsson Review 1982:1. In Swedish.
ERIGEN - combined Darrieus-Savonius type of windgenerator - technical description of turbine, generator and regulation loops. Author: John Åkerlund. Technical report 1985. In English.
Hybrid Power for Remote Sites - IEEE report on a low-maintenance primary power system for remote telecommunication sites. Author: John Åkerlund. IEEE-Intelec proceedings 1983. In English.
Optimering av effekten från en vindturbin - report on solutions for optimizing and maximizing the output power from a wind turbine by means of computerized regulation loops. Authors: Martin Eriksson and Jan Ottosson. Ericsson Review 1983:3. In Swedish.
Evaluation of Alternative Power Sources for Telecommunications Systems - review and analysis of trends and experiences from testing and operation of alternative power sources Author: John Åkerlund. IEEE-Intelec proceedings 1985. In English.
ERIGEN Data Logger for Solar and Wind Systems - data logger for supervision of solar and wind power systems and collection of meteorological data. Author: Jan Ottosson. Ericsson Review 1987:3. In English.
Data Logger and Remote Control for Hybrid Power Systems - monitoring system for remote sites Authors: John Åkerlund and Jan Ottosson. IEEE-Intelec proceedings 1987. In English.
ERIGEN Power System for Railway Radio Network - primary power supply system in the track radio network of Swedish National Railways - description and operational results. Authors: John Åkerlund and Per Sandvik. Ericsson Review 1987:3. In English.
Erfarenheter av Sol- och Vindkraft i Argentina - experiences from solar and wind power in Argentine. Solutions for powering a radiolink site on 4300 meters height in the Andes. Author: Lars Ejdling. Ericsson Review 1988:2. In Swedish.

*Telecom Power Systems / Strömförsörjning av Telecomanläggningar :*
Microprocessor Control System for Large Power Plants - IEEE report on a general purpose control system for telecom power plants. Author: Christer Boije af Gennäs. IEEE-Intelec proceedings 1983. In English.
TeleEnergy Plants in the Perspective of Quality - the "value for money"-concept applied to the performance of telecom energy systems, including a Total Cost Model. Author: Christer Boije af Gennäs. IEEE-Intelec proceedings 1992. In English.

Solutions to Energy Infrastructure Vulnerability of Society Lösningar på samhällets energisårbarhet
*Reserve Power Islands - PremiumEl* */ Reservkraftöar - PremiumEl*
PremiumEl - Presentation - reserve power islands secure the urgent availability of electrical power in the modern society. Author: Christer Boije af Gennäs. Uninterrupted Power Networks UPN 2007-01-10. In English.
DC powering of Internet certifies for telephony - internet telephony calls for increased availability of power. Author: John Åkerlund. TELESCON 3:rd Int'l Telecom Energy Conference Proceedings, May 2000. In English.
Internet and Broadband Society Needs New Power Distribution - the upgrade to the distribution network could be implemented by means of hybrid power and optical fibre cables. Author: John Åkerlund, Olle Hanson. IEEE-Intelec proceedings 2003. In English.

*Debate articles / Debattartiklar:*
El-stopp kan släcka Nödsystemen - alarming report about the vulnerability of internet and IP-telephony as public emergency systems. Authors: Åke Pettersson, Mats Brunell, John Åkerlund. Dagens Nyheter 2002-02-20. In Swedish.
Minska sårbarheten med Publik Reservkraft - proposing overlay electrical grids with centralized backup power systems for qualified loads. Authors: Åke Pettersson, Mats Brunell, Christer Boije af Gennäs. Dagens Industri 2003-10-03. In Swedish.
Reservkraftöar kan minska sårbarheten i Internetsamhället - "reserve power islanding" as a means of decreasing vulnerability of a society that is increasingly dependent on communication over internet and other networks. Authors: Åke Pettersson, Mats Brunell, Christer Boije af Gennäs. Dagens Industri 2004-09-24. In Swedish.
Elnätsbolagens insatser bra, men räcker inte - 99,99% availability of the power grid is far from sufficient. Upgrading the entire grid is not out of place - but a very expensive solution. Dedicated efforts with overlay networks for critical loads would be far more efficient. Authors: Torbjörn Johnson. Dalarnas Tidningar 2004-10-07. In Swedish.
Kom till skott med publik reservkraft - the disastrous storm Gudrun, causing long term disturbances in major parts of Sweden, actualizes the concept of public reserve power as an economical way to secure electricity to vital society functions in times of crisis. Authors: Torbjörn Johnson, Christer Boije af Gennäs. Dagens Industri 2005-01-11. In Swedish.
Dyr privat reservkraft - private and dedicated reserve power may be forbiddingly expensive. This can be overcome by public solutions for emergency power, like power islands, where a common reserve power plant may serve a regional area. Author: Torbjörn Johnson. Dagens Industri 2005-02-08. In Swedish.
Hela landet drabbat av elavbrott - DC distribution gives many advantages: high energy efficiency/less energy waste, superior electrical environment, simple back-up with easily applied redundancy facilities. Author: John Åkerlund. E3 Magazine 2005/3. In Swedish.
Bristande elkvalitet åtgärdas enklast och billigast hos kunden - debating the optimal methods for securing electrical energy supply and quality. Based on a research report from Elforsk (Swedish Electricity Research Institution). Author: Editorial. Elforsk Perspektiv 2007/2 In Swedish.

*Reports and investigations / Rapporter och undersökningar*
Immunitetsläget mot transienter och överspänningar i elektriska apparater - report based on interviews regarding transient and overvoltage immunity of electrical devices commonly used in the society. Author: John Åkerlund. Avbrottsfria Kraftnät UPN AB 2003-09-19. In Swedish.
Korta elavbrott kostar miljarder - a project focused on quality of electricity in the public grid shows that the cost for dips and transients is 4 billion plus (SEK/year) in Sweden. Author: John Åkerlund. ERA 2005/1-2. In Swedish.
Elöverföring av god kvalitet - förstudie av projekt Elkvalitet II - a prestudy on quality of electricity. In practical life the responsibility for electricity quality shows an ambiguous picture - the energy supplier (= the network) is responsible for the voltage quality while the user holds responibility for the load current. Authors: John Åkerlund. Anders Mannikoff. Mats Bollen, Sven-Erik Berglund, Ulf Grape, Torbjörn Johnson. Elforsk rapport 06/81. December 2006 In Swedish.

*DC Power Systems for Qualified Load applications / Likströmssystem för avancerade tillämpningar*
One year of operation of a 9 kW HVDC 350 V power plant for Gnesta data center - report on operational experiencies from DC UPS for a server center. Authors: John Åkerlund. Christer Boije af Gennäs, Netpower Labs AB and Guy Ohlsson, Daniel Rosin, Municipality of Gnesta, Sweden. INTELEC 2007 transactions In English.
Comparison of the AC UPS and the DC UPS solutions for critical loads - a conceptual comparison of the inherent properties of the DC UPS and the AC UPS system solutions for uninterruptible operation of data centers and other critical and sensitive loads. Authors: John Åkerlund. Christer Boije af Gennäs, Netpower Labs AB, Sweden. Submitted to IEEE 2007 UPS Conference, but never published. In English.
Whitepaper - Running AC SMPS on DC - Comments to common questions about feeding DC to power supplies originally rated for AC. Author: Christer Boije af Gennäs, Netpower Labs AB, Sweden. Whitepaper from Netpower Labs AB, 2007-12-20. In English.
Edison's Final Revenge - The system of DC power generation and local distribution that the great inventor championed is set for a comeback. Editorial from American Scientist OnLine March-April 2008. In English.