Selaus tekijän mukaan kokoelmassa "Ahola, Jero"Väitöskirjat
Aineistot 1-19 / 19
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Applicability of Power-Line Communications to Data Transfer of On-line Condition Monitoring of Electrical Drives
Acta Universitatis LappeenrantaensisURN:ISSN:1456-4491 (29.08.2003)The research of power-line communications has been concentrated on home automation, broadband indoor communications and broadband data transfer in a low voltage distribution network between home andtransformer station. ... -
Application of software-defined radio for power-line-communication-based monitoring
Acta Universitatis Lappeenrantaensis (Lappeenranta-Lahti University of Technology LUT, 07.02.2020)Power line communication (PLC) is an established telecommunication technology. A PLC-based communication system has the advantage of securing data. transmission over already existing power line networks. In this way, an ... -
Distributed ControlArchitecture of Power Electronics Building-Block-Based Frequency Converters
Acta Universitatis Lappeenrantaensis (Lappeenranta University of Technology, 26.10.2010)The increasing power demand and emerging applications drive the design of electrical power converters into modularization. Despite the wide use of modularized power stage structures, the control schemes that are used are ... -
Energy efficient hydrogen production by water electrolysis
Acta Universitatis Lappeenrantaensis (Lappeenranta-Lahti University of Technology LUT, 28.02.2020)Hydrogen is the most abundant element in the universe. On Earth, it not only forms water molecules, but also commonly combines with carbon into hydrocarbons that power the current world economy. The use of these natural ... -
Energy-efficient control strategies for variable speed driven parallel pumping systems based on pump operation point monitoring with frequency converters
Acta Universitatis Lappeenrantaensis (Lappeenranta University of Technology, 14.03.2014)The pumping processes requiring wide range of flow are often equipped with parallelconnected centrifugal pumps. In parallel pumping systems, the use of variable speed control allows that the required output for the process ... -
In situ hydrogen production in power-to-food applications
Acta Universitatis Lappeenrantaensis (Lappeenranta-Lahti University of Technology LUT, 04.02.2022)Technologies capable of coupling sustainable generation of energy and production of valuable products are required to shift the focus from a fossil economy to a renewablebased and circular economy and to confront environmental ... -
Mobile sensor for measurements inside combustion chamber – preliminary study
Acta Universitatis Lappeenrantaensis (Lappeenranta University of Technology, 15.12.2017)Large industrial boilers continue to grow in size. In the largest ones, the measurement systems no longer reach the inner parts of the combustion chambers. In addition, new measurement solutions are needed due to tightened ... -
Monitoring of centrifugal pump operation by a frequency converter
Acta Universitatis Lappeenrantaensis (Lappeenranta University of Technology, 27.05.2011)Centrifugal pumps are widely used in industrial and municipal applications, and they are an important end-use application of electric energy. However, in many cases centrifugal pumps operate with a significantly lower ... -
Optimizing the specific energy consumption of vacuum filtration
Acta Universitatis Lappeenrantaensis (Lappeenranta-Lahti University of Technology LUT, 13.12.2019)Vacuum filtration is applied in solid-liquid separation in a wide variety of industrial processes for instance in the mining, chemical, and paper industries. The main contributor to the considerable energy consumption of ... -
Power line communication in motor cables of variable-speed electric drives − analysis and
Acta Universitatis Lappeenrantaensis (Lappeenranta University of Technology, 31.10.2008)Data transmission between an electric motor and a frequency converter is required in variablespeed electric drives because of sensors installed at the motor. Sensor information can be used for various useful applications ... -
Power-line-communication-based data transmission concept for an LVDC electricity distribution network – Analysis and implementation
Acta Universitatis Lappeenrantaensis (Lappeenranta University of Technology, 18.12.2013)Communications play a key role in modern smart grids. New functionalities that make the grids ‘smart’ require the communication network to function properly. Data transmission between intelligent electric devices (IEDs) ... -
Radio Frequency Measurement Method for Detecting Bearing Currents in Induction Motors
Acta Universitatis Lappeenrantaensis (Lappeenranta University of Technology, 28.05.2009)Induction motors are widely used in industry, and they are generally considered very reliable. They often have a critical role in industrial processes, and their failure can lead to significant losses as a result of shutdown ... -
Radio-frequency-based measurement methods for bearing current analysis in induction motors
Acta Universitatis Lappeenrantaensis (Lappeenranta University of Technology, 15.12.2014)The most common reason for a low-voltage induction motor breakdown is a bearing failure. Along with the increasing popularity of modern frequency converters, bearing failures have become the most important motor fault ... -
Reduction of non-circulating bearing currents by electrical machine design
Acta Universitatis Lappeenrantaensis (Lappeenranta-Lahti University of Technology LUT, 22.09.2023)Electrical machines and drive systems play a crucial role in industrial processes and everyday life. Electrical drive systems that are capable of operating in the variable speed mode allow applying electric motors for the ... -
Socioeconomic impacts of cost optimised and climate compliant energy transitions across the world
Acta Universitatis Lappeenrantaensis (Lappeenranta-Lahti University of Technology LUT, 17.06.2022)There are undeniable signs from all over the world demonstrating that climate change is already upon us. Numerous scientific studies have warned of dire consequences should humankind fail to keep average global temperatures ... -
Study of inverter-induced bearing damage monitoring in variable-speed-driven motor systems
Acta Universitatis Lappeenrantaensis (Lappeenranta University of Technology, 13.12.2017)Bearing currents are parasitic phenomenon which is commonly present inmodern inverterdriven motors. At this date the root causes of this phenomenon can be considered as well identified - mainly occurring due to magnetic ... -
Utilization of a Time Domain Simulator in the Technical and Economic Analysis of a Wind Turbine Electric Drive Train
Acta Universitatis Lappeenrantaensis (Lappeenranta University of Technology, 13.08.2010)The amount of installed wind power has been growing exponentially during the past ten years. As wind turbines have become a significant source of electrical energy, the interactions between the turbines and the electric ... -
Variable speed drive in fan system monitoring
Acta Universitatis Lappeenrantaensis (Lappeenranta University of Technology, 09.12.2013)Fan systems are responsible for approximately 10% of the electricity consumption in industrial and municipal sectors, and it has been found that there is energy-saving potential in these systems. To this end, variable ... -
Variable-speed-drive-based monitoring and diagnostic methods for pump, compressor, and fan systems
Acta Universitatis Lappeenrantaensis (Lappeenranta-Lahti University of Technology LUT, 05.02.2021)Pumps, fans, and compressors account for nearly a third of the global consumption of electricity. Variable-speed drives (VSD) enable energy-efficient capacity control of these devices, and have thus become a common component ...
