Backup power is essential to supply important functions in society with electricity in case of a blackout. Today in Sweden most backup generators are based on diesel fuel and seldom used, but they are still associated with bad environmental impact while operating. What if a backup system could be designed to increase its value and at the same time lower the environmental impact? This study has investigated alternative solutions for backup power and applied them on a specific case. A food providing industry with great variations in their load profile (40 - 240 kW) is looking for a backup solution able to supply the industry for 12 h in case of a blackout. The study started off by investigating different techniques and their suitability for providing backup power, such as diesel generators (DG), battery energy storage systems (BESS), micro gas turbines (MGT) and fuel cells (FC). Most suitable to be compared with the traditional diesel solutions in terms of cost, climate and technique was found to be two hybrid systems. The first one a combination of a DG and BESS and the second a combination of a MGT and BESS. The two hybrid systems were primarily dimensioned to a size of 100 kW (DG/MGT) with a 350/350 kWh/kW BESS based on terms and after analyzing the industry's load profile. The two hybrid systems were compared with a 350 kW DG in two aspects over a time frame of 15 years, life cycle costs (LCC) and carbon dioxide emissions. Compared with only DG the result showed a 15% LCC increase and a 26% emission reduction for the hybrid solution with DG + BESS. For MGT + BESS the LCC increase was 30% but the emission reduction was 52%. Included into the LCC analysis is utilization of the BESS for grid services such as peak shaving, arbitrage and grid support which had a major positive economic impact. The LCC results were however sensitive to changes in some parameters such as investment costs and rates. Finally, the study tried to optimize the cost and climate performance of the two hybrid systems. By reducing a few terms, sizing of the systems could be adjusted. This resulted in both hybrid systems being more profitable and climate friendly with a larger DG/MGT and a smaller complementing BESS for peak loads, outperforming the only DG solution.

Datahallar behöver reservkraft av god kvalitet för att garantera upprätthållandet av dess funktion. Laster i en datahall kommer att generera ström och spänningsövertoner som kan skapa problematik med elkvaliteten. Coromatic är intresserade av att veta mer hur dessa laster påverkar reservkraftsgeneratorn. En mätning utfördes på en datahall under ett funktionsprov. Resultatet blev att halten av THD ökade, främst är det 3:e övertonen som är framträdande. Mätvärdena för THDV ligger under gränsvärdena för SS-EN 50160 och 61000-2-2, men gränsvärdena för 3:e ton ligger långt över. Ingen åtgärd föreslås i nuläget för att hantera problemet. Denna avhandling har gett värdefull information till Coromatic att ta i beaktande vid utförande av nya reservkraftsanläggningar. / A facility full with computers needs backup-power to guarantee the function. Loads in this facility will produce current and voltage harmonics that can pollute and cause trouble with the quality of electricity. Coromatic are interested in knowing more about how these loads can affect the generator. A measurement was performed on a facility when they ran a functional test. The results indicated that THD increased, the third harmonic turned out to be the single harmonic with the highest value. The value is within the boundaries for THDV according to SS-EN 50160 and 61000-2-2, except for the third harmonic. Its value was far too high. No action is propsed to deal with the problem at the moment. This thesis has provided Coromatic with valuable information too consider when they building new systems.

Fuel cell technology has undergone significant development in the past 15 years, spurred in part by its unique energy conversion characteristics; directly converting chemical energy to electrical energy. As fuel cell technology has past through the prototype/pre-commercialisation development, there is increasing interest in manufacturing and application issues. Of the six different fuel cell types pursued commercially, the Proton Exchange Membrane (PEM) fuel cell has received the greatest amount of research and development investment due to its suitability in a variety of applications. A particular application, to which state-of-the art PEMFC technology is suited, is backup/uninterruptible power supply (UPS) systems, or stand-by power systems. The most important feature of any backup/UPS system is reliability. Traditional backup power systems, such as those utilising valve regulated lead acid (VRLA) batteries, employ remote testing protocols that acquire battery state-of-health and state-of-charge information. This information plays a critical role in system management and reliability assurance. A similar testing protocol developed for a PEM fuel cell would be a valuable contribution to the commercialization of these systems for backup/UPS applications. This thesis presents a novel testing and analysis procedure, specifically designed for a PEM fuel cell in a backup power application. The test procedure electronically probes the fuel cell in the absence of hydrogen. Thus, the fuel cell is in an inactive, or passive, state throughout the testing process. The procedure is referred to as the passive state dynamic behaviour (PSDB) test. Analysis and interpretation of the passive test results is achieved by determining the circuit parameter values of an equivalent circuit model (ECM). A novel ECM of a fuel cell in a passive state is proposed, in which physical properties of the fuel cell are attributed to the circuit model components. Therefore, insight into the physical state of the fuel cell is achieved by determining the values of the circuit model parameters. A method for determining the circuit parameter values of many series connected cells (a stack) using the results from a single stack test is also presented. The PSDB test enables each cell in a fuel cell stack to be tested and analysed using a simple procedure that can be incorporated into a fuel cell system designed for backup power applications. An experimental system for implementing the PSDB test and evaluating the active performance of three different PEM fuel cells was developed. Each fuel cell exhibited the same characteristic voltage transient when subjected to the PSDB test. The proposed ECM was shown to accurately model the observed transient voltage behaviour of a single cell and many series connected cells. An example of how the PSDB test can provide information on the active functionality of a fuel cell is developed. This method consists of establishing baseline performance of the fuel cell in an active state, in conjunction with a PSDB test and identification of model parameter values. A subsequent PSDB test is used to detect changes in the state of the fuel cell that correspond to performance changes when the stack is active. An explicit example is provided, where certain cells in a stack were purposefully humidified. The change in state of the cells was identified by the PSDB test, and the performance change of the effected cells was successfully predicted. The experimental test results verify the theory presented in relation to the PSDB test and equivalent circuit model.

The aim of this study is a design of a control and signalling unit for sport meetings controlled by a microcontroller. The unit should display the time, the state of the match, eventually another data important for a course of the match. It should be fitted by an audible alarm of the end of the match. A touch control panel with a liquid crystal display serves as input of control data. The unit operates in a countdown mode, it is possible anytime to start or to stop the time by pressing the button. The equipment is mains-operated and backed up by an external battery. In the case of a power failure, it is switched over to the battery. A representation of the time, the state of the match and other data is done by LED displays. The unit allows a connection to PC.

Dagens samhälle är uppbyggt av ett konstant energiberoende för att få samhällets alla funktioner att fungera. Ett strömavbrott kan därför bli förödande där kontinuerlig tillgång till elektricitet behövs, trots att Sverige har starka elnät har kravet att alltid ha tillgång till elektricitet öppnat upp en marknad för reservkraft. Syftet med det här arbetet var att ta fram kursmaterial för att läsaren ska få en övergripande kunskap om reservkraft med inriktning på dieselkraft. Det framtagna kursmaterialet består av rekommendationer i form av sidhänvisningar ur källor som kan användas vid sammanställning av undervisningsmaterial. Kompendiematerialet kompletteras med en PowerPoint-struktur som kan användas i undervisningssyfte. Genom att studera relevanta källor har vi fördjupat oss i ämnet dieselaggregat och har plockat ut sidhänvisningar enligt kopieringsavtalet, som gäller för högskolan, som vi anser passa bra vid skapandet av ett kompendium. Vi har även strukturerat en grund till en PowerPoint som kan underlätta vid skapandet av föreläsningsmaterial.Denna rapport förklarar ett dieselaggregats tekniska uppbyggnad och vad som är viktigt att tänka på vid dimensionering av ett aggregat. Rapporten tar även upp rekommenderat underhåll samt de miljö- och säkerhetskrav som ställs på att aggregat. / Today's society is composed of a constant energy dependency to get all functions of the modern society to function, a power failure can be devastating. Even though Sweden has a strong power grid, the requirement to always have access to electricity has opened up a market for back-up power. The aim of this work was to create material that could be used in educational purpose and for the reader to get a basic understanding of back-up power with focus on diesel generated power. The course material consists of recommendation of content in the form of page references from sources that fit well in the compilation ofeducation material in the form of a compendium. The compendium is supplemented with a layout of a PowerPoint presentation that can be used for educational purposes. By studying the relevant sources, we have deepened in our topic diesel generated power and have picked out page references, in accordance with the agreement regarding the school copy law, which we consider to be a good fit for the creation of a compendium. We have also created a foundation to a PowerPoint that can facilitate the creation of lecture material. This report explains the structure of a diesel power generator and what is important to consider when sizing a power system. The report also discusses recommended maintenance as well as the requirements placed on a diesel power generator.

This work deals with the design and realization of a modular security central unit's hardware positioned in familial houses. As an operating component of the central unit is used Module Rabbit 3365 with an integrated Ethernet interface. Based on user's requirements and general requirements for electronic security system, circuit diagrams of the central unit's motherboard and power supply with a function of backup power supply are designed. The work also includes layout of a keyboard and LCD display. Printed circuit boards are designed, produced and assembled. The device is set to work. The last part concerns programming of the module Rabbit 3365 in Dynamic C. Gradually, set of operating functions for individual components of the security central unit are implemented.

Kungälv Energi äger och ansvarar idag över Kungälv Kommuns elnät. Med en ökande befolkningsmängd ställs allt högre krav på elnätet och framför allt leveranssäkerheten. Med kalla vintrar och stort energibehov ger detta upphov till en svårare situation gällande leveranssäkerhet. I nuläget har Kungälv Energi två mottagarstationer, en 130/10kV-station espektive 130/20kV-station. 30/10kV-stationen börjar närma sig en gräns där effektbehovet närmar sig den maximala istributionskapaciteten. Därför fastställs en plan för att kunna klara av effektbehovet vid averi på en av två 130/10kV-transformatorer i mottagarstationen M1. Resultatet av rapporten visar att tillräcklig kapacitet finns i närliggande fördelningsstationer för att klara av reservdrift under hög belastning utan att några övriga komponenter skadas. Rapporten behandlar främst effektflöden för att kontrollera att dessa ej överskrider transformatorernas, ledningarnas och kablarnas märkeffekt. I flertalet fall har även faktorer för nödbelastning räknats med vilket resulterar i att samtliga linjer hos Kungälv Energi klarar av den ökade belastningen. Upptäckta flaskhalsar i nätet har uppmärksammats och delgetts samt förslag till förändringar för att förhindra framtida problem. / Kungälv Energi owns and is responsible of Kungälv municipality's electricity grid. With an increasing population and increasing demands on the grid and especially security of supply. With cold winters and large energy gives rise to a more difficult situation regarding security of supply. Currently, Kungälv Energi two receiving stations, a 130 / 10kV station and 130 / 20kV station. 130 / 10kV station is approaching a point where power demand is approaching the maximum distribution capacity. Therefore sets out a plan to cope with the power demand at the failure of one of two 130 / 10kV transformers of the receiving station M1. The results of the report shows that sufficient capacity is available in nearby distribution stations to cope with the emergency operation under high loads without any other components damaged. The report deals primarily with power flows to check that they do not exceed transformers, lines and cables rated power. In the majority of cases have also factors for distress load been counted with, which gives the result that all lines of Kungälv Energi can handle the increased load. Detected bottlenecks in the network have been highlighted, communicated and proposed changes to Kungälv Energi to prevent future problems.

The thesis described the proposal for a wireless network problems. There are recorded and compared the characteristics of different wireless technologies. The possibility of voice communication securing is outlined and solutions implemented in the form of ZRTP protocol. The requirements for quality of service are discussed and the solutions to this issue are proposed. Other chapters are devoted to the actual design of specific equipment, including antennas and advance resource. The whole network is practically implemented in the mountainous countryside of eastern Wallachia. In conclusion, this work is network mate in terms of QoS (quality of service) and tested in terms of prioritization of voice communication.

The thesis deals with Uninterruptible Power Supply (UPS) and associated problems of backup power in case of unexpected outages of electricity. Start of work is dedicated to limitation of the electricity supplies, as well as their causes and consequences. Furthermore, brief history of UPS and subsequently distinguish between UPS’s architectures. There is also a description of the energy sources such as batteries, flywheels or fuel cells. Part of thesis describes security of electricity supply in health care facilities, including requirements for emergency power. The own design of UPS is described in the end.

The thesis deals with Uninterruptible Power Supply (UPS) and associated problems of backup power in case of unexpected outages of electricity. Start of work is dedicated to limitation of the electricity supplies, as well as their causes and consequences. Furthermore, brief history of UPS and subsequently distinguish between UPS’s architectures. There is also a description of the energy sources such as batteries, flywheels or fuel cells. Part of thesis describes security of electricity supply in health care facilities, including requirements for emergency power. The own design of UPS is described in the end.