다중혈관 관상동맥 환자에서 y-문합을 이용하여 양쪽 내흉동맥만을 사용한 우회술의 조기 성적

Squaring hourly demand and wind-solar production data for Germany and a number of neighbouring countries with the results of the EU’s ESTORAGE project, this paper studies the limits of Germany’s energy revolution in view of the volatility of wind and solar power In addition to pumped storage, it considers double-structure buffering, demand management, Norwegian hydro-dam buffering and international diversification via grid expansion If Germany operated in autarchy and tried to handle the volatility of wind-solar production without using stores while replacing all nuclear and fossil fuel in power production, on average 61%, and at the margin 94%, of wind-solar production would have to be wasted, given the current level of other renewables To avoid any waste, the wind-solar market share in an autarchic solution must not be expanded to more than 30% By using Norway’s hydro plants the share could be expanded to 36% If Norway were to build all the pumped-storage plants the ESTORAGE study deems feasible, Germany’s wind-solar market share could be expanded by another 24 percentage points to about 60%, which corresponds to 48% of the combined German and Norwegian markets Additionally expanding the market to Switzerland, Austria and Denmark and building the maximal number of pumped stores would increase the combined wind-solar market share for all five countries to nearly 50%

Buffering Volatility: A Study on the Limits of Germany’s Energy Revolution

This paper deals with the use of least mean squares (LMS, NLMS) and recursive least squares (RLS) algorithms for total harmonic distortion (THD) reduction using shunt active power filter (SAPF) control. The article presents a pilot study necessary for the construction of our own controlled adaptive modular inverter. The objective of the study is to find an optimal algorithm for the implementation. The introduction contains a survey of the literature and summarizes contemporary methods. According to this research, only adaptive filtration fulfills our requirements (adaptability, real-time processing, etc.). The primary benefit of the paper is the study of the efficiency of two basic approaches to adaptation ((N)LMS and RLS) in the application area of SAPF control. The study examines the impact of parameter settings (filter length, convergence constant, forgetting factor) on THD, signal-to-noise ratio (SNR), root mean square error (RMSE), percentage root mean square difference (PRD), speed, and stability. The experiments are realized with real current and voltage recordings (consumer electronics such as PC source without power factor correction (PFC), HI-FI amplifier, etc.), which contain fast dynamic transient phenomena. The realized model takes into account a delay caused by digital signal processing (DSP) (the implementation of algorithms on field programmable gate array (FPGA), approximately 1–5 μs) and a delay caused by the reaction time of the proper inverter (approximately 100 μs). The pilot study clearly showed that the RLS algorithm is the most suitable for the implementation of an adaptive modular inverter because it achieved the best results for all analyzed parameters.

Least Mean Squares and Recursive Least Squares Algorithms for Total Harmonic Distortion Reduction Using Shunt Active Power Filter Control

With the development of modern industrial technology a large number of non-linear loads are used in power system, which causes harmonic distortion in the power system. At the same time the power quality and safe operation becomes inferior. Therefore mitigation of harmonics is very necessary under the situation. This paper presents the design of two passive filters to reduce the current harmonics produced by nonlinear loads in industrial power system. Matlab /simulink software has been used for the simulation purpose. The results have been obtained with and without installation of filters and then it is observed that after installation of filters harmonics of the current are reduced and power factor is improved.

Harmonics Mitigation of Industrial Power System Using Passive Filters

Electricity has been one of the most important necessities for industrialization, increasing living standard of people
around the world. Power electronic devices are applied in industry as well as in domestic appliances. The excessive use of
these devices cause power quality (PQ) problems in the power system (PS), due to generation of harmonics. The
consequences of harmonics include; increased probability in occurrence of resonance, neutral overload in 3-phase systems,
overheating of all cables and equipment, loss of efficiency in electric machines, electromagnetic interference with
communication systems, errors in measurements when using average reading meters, nuisance tripping of thermal protections.
Many researches are being done to find out the best solution against the cause. For this, various tools and techniques are being
improved and applied to mitigate such cause and enhance the PQ of the PS. One of the methods to mitigate harmonics is by
designing and using passive filter. Moreover, it reduces the need of capacitor for supplying extra needed kVAr. Due to these
two attracting features of Passive filter, its design and application can be found in many reasearches. The the main aspect of
filter design has been challenging issue. This paper presents the optimal design of single tuned passive filter that its
application is to mitigate harmonics in power frequency. The optimal parameters of this filter were calculated by using
Lagrange interpolation method. The results were obtained by Matlab/simulation which shows the effectiveness of this filter.

Optimal design of a single tuned passive filter to mitigate harmonics in power frequency

The paper has been intended to present the analysis of hybrid power filter (HPF) dynamical properties. The hybrid power filter with single tuned passive filter has been taken into consideration. The present paper deals with influence of control algorithm and its components on dynamical properties of HPF. Simulation and experimental results of transient states have also been included in the article. Streszczenie. W pracy zaprezentowano zagadnienia związane z wlaściwościami dynamicznymi hybrydowego energetycznego filtru aktywnego (HEFA) w konfiguracji z filtrem pasywnym jednej harmonicznej. Skupiono sie na wplywie parametrow algorytmu sterowania na wlaściwości dynamiczne ukladu HEFA. Przedstawiono wyniki badan symulacyjnych oraz laboratoryjnych w stanach przejściowych pracy ukladu. (Wlaściwości dynamiczne energetycznego filtru hybrydowego z filtrem pasywnym dla jednej harmonicznej).

Dynamical properties of hybrid power filter with single tuned passive filter

The paper includes a summary and a background of long-time research conducted by a research team in the Institute of Electrical Engineering and Computer Science at Silesian University of Technology. The research work has principally been related to selected problems in the field of analysis and synthesis of systems aimed at symmetrisation and improvement of some power quality parameters. This paper constitutes a first part of the report on the research. It has been devoted to effective elimination of higher harmonics and reactive power compensation by means of parallel active power filters. The other problem discussed in this paper is related to this issue and it is very important from the economic point of view; it addresses optimal sizing and placement of active power filters in investigated power networks.

/pdf/selected-methods-for-improving-operating-conditions-of-three-3enkkfnxd3.pdf

Selected methods for improving operating conditions of three-phase systems working in the presence of current and voltage deformation – part I

The paper is related to the problem of modeling and optimizing power systems supplying, among others, nonlinear loads. A software solution that allows the modeling and simulation of power systems in the frequency domain as well as the sizing and allocation of active power filters has been developed and presented. The basic assumptions for the software development followed by the models of power system components and the optimization assumptions have been described in the paper. On the basis of an example of a low-voltage network, an analysis of the selection of the number and allocation of active power filters was carried out in terms of minimizing losses and investment costs under the assumed conditions for voltage total harmonic distortion (THD) coefficients in the network nodes. The presented examples show that the appropriate software allows for an in-depth analysis of possible solutions and, furthermore, the selection of the optimal one for a specific case, depending on the adopted limitations, expected effects, and investment costs. In addition, a very high computational efficiency of the adopted approach to modeling and simulation has been demonstrated, despite the use of (i) element models for which parameters depend on the operating point (named iterative elements), (ii) active filter models taking into account real harmonics reduction efficiency and power losses, and (iii) a brute force algorithm for optimization.

Software Solution for Modeling, Sizing, and Allocation of Active Power Filters in Distribution Networks

The comparison of performance and accuracy of the active power filter control algorithm realizations has been presented in the paper. The worked out algorithms are based on dq synchronous frame control strategy. The following Texas Instruments digital signal controllers were used for the realization: fixed-point TMS320F2812 and floating-point TMS320F28335. The TMS320F28335 digital signal controller is the first floating-point controller in the C2000 family. It combines flexible control-specific interfaces and ease of use of an industrial microcontroller(MCU) with the processing power of DSP technology (up to 300 MFLOPS). Using of the floating-point digital signal processor allows improving accuracy of the computation, particularly in digital filtering (IIR low-pass filter) which has a direct influence on the quality of the generated current waveforms. The worked out algorithms have been practically verified on APF prototype which was built in the Institute of Industrial Electrical Engineering and Computer Science. The presented problems have been illustrated by laboratory results.

Performance and accuracy comparison of fixed and floating-point realizations of the Active Power Filter control algorithm

Hybrydowe energetyczne filtry aktywne

Handle everyday research tasks with reliable, citation-backed results

Your personal Research Agent to handle research tasks with citation-backed results

Popular Tasks used by Researchers

How can I help with your research?

Meet SciSpace

Get more enhanced response by uploading the PDFs you want me to reference.

No relevant PDFs in your library

SciSpace is the AI research assistant for academics. Run systematic literature reviews on 280M+ papers, and write papers with cited sources. Trusted by 1M+ students, PhDs & researchers.

SciSpace | AI for Research

Analyze PDFs

Code & Manuscripts

Funding & Grants

Literature & Patents

Medical & Clinical Data

Systematic Review

Visualize & Present

Web & Data

Build a Google Scholar-like website for your research.

Build a website

Create charts and images for your research

Create a Chart

Write a paper for submission to a journal

Draft a manuscript

Patent Search

Design eye-catching scientific posters in minutes.

Scientific Poster Generation

Systematic Literature Review

One task is running at the moment. Your messages will be shown right after.

Drag and drop or click here to browse

Loved by <highlight>1 million+</highlight> researchers

Extract a list of specific topics and their sources from unstructured text

Topics

Compare and analyze relevant papers that matches with your search

Papers

Get insights from PDFs and bookmarked papers from your library

My library

Recent searches

Try searching for:

Catch AI-generated content in scholarly and non-scholarly content

{ai} Detector

Ai Writer

Get PDF Summaries, highlighted text explanations 

Chat with PDF

Effortlessly create in-text citations and bibliographies in APA and 2,500 other formats

Citation generator

Get explanations, summaries, and answers on academic papers

Ease up your research workflow with {scispace}'s cohort of exciting AI tools

Elevate your academic writing skills and convey your ideas the way you want

Paraphraser

Explore our range of reading and writing tools

Your file is being prepared and should be ready in a few minutes. If it's a large file, it might take a bit longer. You can close this window, and we'll email you the file when it's done.

You have reached a maximum limit of <strong>{limit}</strong> columns in the table. Remove at least <strong>1</strong> column to add or create another one.

D. Buła

Author Tools

Chat about Author