Normally the operational amplifier is used as a component in active filter design. The goal for future components in filter design is large bandwith and the use of low supply voltages. The use of current-mode instead of voltage-mode circuits gets a step closer to the required performance. A component that use current as the signal conveying part is the Current conveyor. In this report a comparative study between two Current conveyor structures of second generation (CCII) is performed.

A Current conveyor is an active building block that can be used to implement most active and passive components. It differs from the operation amplifier in that it uses current instead of voltage. The Current conveyor also has significantly higher voltage gain over a broader frequency range. To simplify the construction of analogue circuits and increase the construction efficiency it is desirable to use a top-down methodology. This means that the whole system is partitioned into a hierarchy of subsystems.

This report is the result of a project work carried out at Karlstad University in conjunctionwith the local consulting firm Camatec where most of the work has been performed.The work can be classified as a classic engineering work with supportive theories andcalculations which in this context is relevant.The engineering project has focused on developing new standards for a conveyor that is usedin the Värmland paper industry where large rolls of paper are produced. A conveyor can takeits appearance in many different forms but in this thesis it has been an exemplary look and ithas also become modulatable with a central section, a drive end and a turning end.The construction work has been build under CAD programs such as Pro Engineer, drawingshave been created and costings have been analyzed. Strength calculations have been made andcooperation from several different companies have erected to explore different solutions andideas for a modern and sustainable conveyor..

The project was carried out with SwedSafe AB, engaged in hearing and manufacture of earplugs. Since the company is a world leader in the sale of these products, it is important that they keep a higher level of quality of these products.Production of earplugs is currently a automated manufacturing process that is divided into four conveyor belts and one of the conveyor belts is what will be affected in the project. The belt affected during this process is exposed to various elements such as filling, closing, fermentation and extraction of products. Because the belt gets dirty, degraded products and the work environment is affected. To increase the quality of products and improve the working environment requires an automatic cleaning process, which collects dirt from the belt.The aim of the project is to design a machine that prevents the belt from becoming dirty, preserve molds clean and improve the working environment without disrupting production.

Mek Stans 07 is a machine developed for Tetra Pak in Lund as a 10p candidate theses project at Halmstad University. The commission behind the project involved development of a machine that punches holes in packages for the inspection division at Tetra Pak. The task for the machine was to facilitate the process of making openings for testing in the company?s other equipment. Researches on different methods of cutting, types of automatization and possible designs were made. To implement the project a design and construction from the base where chosen.

A study was made to evaluate how current measurementscould help to determine how particles from fish farms are dispersed. During sixweeks of the summer 2012, two different current measurements were conducted.One of them consisted of measurements each fifth minute at 5 m and 15 m atthree locations for 14-16 days each. The other consisted of profilemeasurements at each location at four times during the period of six weeks. Forthe current measurements two instruments (model RCM 9) were used. A two weekmeasurement can give enough data to make an evaluation of how the currents at alocation will transport litter from a fish farm.

This thesis work is about how technical consulting companies can accept their organization before a coming recession. Technical consulting companies are together with the rest of the actors in the construction business constantly depended on the current economic situation on the market. How to adapt the organisation depends on the current situation on the market.To adapt the organization in the best way possible the companies need to recruit and educate personal. It is then very important to find a solution on how the current change of generation in the companies will be handled. The large and very much competent group of 40-talists will in a few years retire.

Through a thorough analysis of the current situation, we have highlighted differences inworking methods for the various workshops and drew up proposals for improvements incombination with a practical work description that can be implemented in the company..

During year 2004 Ålö AB made significant change in their production process. The production of front loaders is nowadays highly automated with short operation times. To be able to control their process in a better way Ålö recently decided that they needed a tool for simulation of their production and to shift patterns. This final thesis started with a pilot study in Ålö?s factory in Brännland.

Examensarbetet har gjorts i samarbete med Hjort Conveyor, ett företag i Helsingborg som tillverkar conveyorsystem för transportering av gods inom processindustrin.Vårt uppdrag har varit att ta fram ett kostnadseffektivt och kommersiellt hållbart styrsystem till deras applikation för lodrät transportering. Funktionskraven har varit parallellreglering, enkeldrift, samt reglering av balk i vinklat läge.Denna rapport omfattar vårt arbete med val av komponenter, programmering av styrprogrammet och installation av systemet. Även drifttagningen, som sketts på en testanläggning hos Linde Metallteknik AB tas upp.Projektets samtliga krav har uppfyllts och testanläggningen används idag i produktion hos Linde Metallteknik AB..

Examensarbetet har gjorts i samarbete med Hjort Conveyor, ett företag i Helsingborg som tillverkar conveyorsystem för transportering av gods inom processindustrin.Vårt uppdrag har varit att ta fram ett kostnadseffektivt och kommersiellt hållbart styrsystem till deras applikation för lodrät transportering. Funktionskraven har varit parallellreglering, enkeldrift, samt reglering av balk i vinklat läge.Denna rapport omfattar vårt arbete med val av komponenter, programmering av styrprogrammet och installation av systemet. Även drifttagningen, som sketts på en testanläggning hos Linde Metallteknik AB tas upp.Projektets samtliga krav har uppfyllts och testanläggningen används idag i produktion hos Linde Metallteknik AB..

This master thesis has been performed at Vattenfall Power Consultant in Gothenburg and Trollhättan for Vattenfall Vattenkraft. In this report vacuum circuit breaker in small-scale hydropower stations with the rated power 4 MVA and below has been studied. Models of the stations are modeled and analyzed in PSCAD/EMTDC to study the high voltage transients that are created after current chopping with vacuum circuit breaker. Vacuum circuit breaker may chop the current before it reaches zero value, which means that high voltage transients can be created. The equipment of the stations can be destroyed by high voltage transients.The purpose of this thesis is to examine the use of vacuum circuit breaker in small-scale hydropower stations and the risk for high voltage transients from current chopping.According to the results there is a risk of high voltage transients after current chopping with small synchronous generators in stations with the operating voltages 0.4 kV and 3.6 kV.

During this master thesis, wear and friction properties for the high-temperature alloy Kanthal APMT were studied. The results were also compared to 253MA. The initial tests showed, among other things, that the surface fineness of the muffle tubes matters in real applications like conveyor belts. A 253MA-sample wear-tested against a 253MA-tube showed lowest wear at 900°C while a pre-oxidized APMT-sample wear-tested against a APMT-tube had the lowest mean value of the friction force at 1100°C, compared to all other tests..

Mechanical relays are more and more being replaced with semiconductortechnology. In this thesis it is investigated if and how the larger loads couldbe controlled by transistors. The main part of this work aims to create andverify a solution that can control the starter motor, as well as protect it incase of any failure. The different malfunctions that the solution protectsagainst is high current, too high peak current, low current, maximum cranktime and minimum cool off time. The timers also protect indirectly againstoverheating of the starter engine.The transistors used are BTS555, from Infineon.

We got in contact with Marco AB, who we?ve had contact with before concerning earlier projects, to find out if they were interested in arranging a larger project for our last class (Examensarbete 15hp). They were very positive to this proposition, and soon they offered us a project regarding reconstruction of their current mechanical device that absorbs all the force from the lift itself when it is at a predefined level (sv. sjunkspärr). The current solution does fulfill the requirements that are given, however it is not a solution that gives a high level of satisfactory.