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Tytuł:
A comparative study of the effects of hyperbaric oxygenation on heart rate variability using wavelet analysis and fast Fourier transform
Studium porównawcze nad wpływem tlenowej terapii hiperbarycznej na zmienność rytmu zatokowego przy wykorzystaniu analizy fali elementarnej i szybkiej transformaty Fouriera
Autorzy:
Juvet, T.
Abdelhadi, S.
Powiązania:
https://bibliotekanauki.pl/articles/366277.pdf
Data publikacji:
2013
Wydawca:
Polskie Towarzystwo Medycyny i Techniki Hiperbarycznej
Tematy:
hyperbaric oxygenation
heart rate variability
wavelet analysis
EKG
RR interval
high-frequency power
low-frequency power
tlenowa terapia hiperbaryczna
zmienność rytmu zatokowego
analiza fali elementarnej
odstęp RR
moc wysokiej częstotliwości
moc niskiej częstotliwości
Opis:
Heart rate variability (HRV) is a recognized and reliable parameter of the autonomous nervous system’s effects on the heart. Hyperbaric oxygenation (HBO) has been shown to increase HRV and decrease heart rate suggesting increased vagal tone. Several methods have been developed to analyze HRV, including time-domain, frequency-domain and wavelet time/frequency analysis. To compare the use of these methods in analyzing HRV over shorter periods of time, electrocardiogram recordings were made of 6 subjects under normal resting conditions, followed by breathing 100% O2 at 253 kPa (2.5 ATA) of pressure. HRV was analyzed over two and ten minute periods using both fast Fourier transform and wavelet analysis. Results showed that wavelet and FFT analyses have similar diagnostic features, with continuous wavelet analysis appearing more suitable in detecting changes in HRV over shorter time periods.
Zmienność rytmu zatokowego (HRV) jest sprawdzonym i niezawodnym parametrem mierzącym wpływ autonomicznego układu nerwowego na pracę serca. Badania wykazały, że hiperbaryczna terapia tlenowa (HBO) powoduje zwiększenie HRV oraz redukcję w częstotliwości akcji serca, sugerując tym samym zwiększenie napięcia nerwu błędnego. W celu dokonania analizy HRV wykorzystano kilka metod, w tym analizę czasową, analizę w dziedzinie częstotliwości oraz czasowo-częstotliwościową analizę fali elementarnej. W celu porównania skuteczności tych metod w krótkookresowej analizie HRV, sześciu pacjentów poddano badaniu przy użyciu elektrokardiogramu w warunkach spoczynku, a następnie zlecono im oddychanie 100% O2 pod ciśnieniem 253 kPa (2,5 ATA). HRV analizowano w okresach dwu- i dziesięciominutowych przy użyciu szybkiej transformaty Fouriera (STF) i analizy fali elementarnej. Wyniki wykazały podobieństwa cech diagnostycznych obu metod, przy czym stwierdzono, iż nieprzerwana analiza fali elementarnej osiąga lepsze wyniki w wykrywaniu zmian w HRV w krótszych przedziałach czasowych.
Źródło:
Polish Hyperbaric Research; 2013, 4(45); 19-36
1734-7009
2084-0535
Pojawia się w:
Polish Hyperbaric Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A diode-pumped high-repetition-frequency passively Q-switched Nd:LaMgAl11O19 laser
Autorzy:
Xu, Yan
Gao, Ziye
Xia, Guangqiong
Wu, Zhengmao
Powiązania:
https://bibliotekanauki.pl/articles/1835801.pdf
Data publikacji:
2020
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
Nd:LaMgAl11O19 disordered crystal
Q-switched laser
high pulse repetition frequency
PRF
semiconductor saturable absorber mirror
SESAM
laser diode
LD
Opis:
High-repetition-frequency Q-switched laser is realized through adopting a Nd:LaMgAl11O19 (Nd:LMA) disordered crystal as the gain material, a laser diode lasing at 796 nm as the pumped source, and a semiconductor saturable absorber mirror (SESAM) as the Q-switched device. The out-put characteristics are analyzed under using different transmittance T plane mirrors as an output coupler. Without adopting SESAM, the laser is operating at a CW state, and a relatively high transmittance is helpful for achieving high output power, slope efficiency and light-to-light efficiency. ForT = 7.5% and an absorbed power of 6.17 W, the output power arrives at its maximum of 1160 mW,and the corresponding slope efficiency and light-to-light efficiency are 20.71% and 18.78%, respectively. After introducing SESAM into the cavity, the laser operates at a passively Q-switched state, and the largest slope efficiency is 13.14% under T = 5.0%. Adopting five different output couplers, with the increase of the absorbed power, the pulse repetition frequencies, the pulse energies and the peak powers will ascend while the pulse widths will decline. The observed narrowest pulse width, the maximum pulse repetition frequency, the highest pulse energy and peak power are 1.745 μs, 175.88 kHz, 3.21 μJ and 1.84 W, respectively.
Źródło:
Optica Applicata; 2020, 50, 3; 415-423
0078-5466
1899-7015
Pojawia się w:
Optica Applicata
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A High Capacity Energy Efficient Approach for Traffic Transmission in Cellular Networks
Autorzy:
Esmaeilifard, M.
Rahbar, A. G.
Powiązania:
https://bibliotekanauki.pl/articles/958113.pdf
Data publikacji:
2015
Wydawca:
Instytut Łączności - Państwowy Instytut Badawczy
Tematy:
cellular networks
energy efficiency
frequency assignment
interference avoidance
transmission power control
Opis:
The efficiency of cellular networks can be improved in various aspects such as energy consumption, network capacity and interference between neighboring cells. This paper proposes a high capacity energy efficient scheme (HCEE) for data transmission in cellular networks in a country area. In this paper, the authors obtain a new equation to characterize the minimal required output power for traffic transmission between a base station (BS) and a mobile user (MU) based on the MU distance from the BS. Also, the cells boundaries (the boundary of overlapping areas of neighboring cells) by two static and dynamic approaches are specified. This work helps for better frequency allocation to MUs and allows increasing network capacity. In this paper, the analytical modeling in order to formulate the HCEE algorithm and evaluate its performance is used. The performance evaluation results show the simplicity of the HCEE algorithm and its effect on energy consumption decline, network capacity enhancement and the interference reduction.
Źródło:
Journal of Telecommunications and Information Technology; 2015, 3; 5-12
1509-4553
1899-8852
Pojawia się w:
Journal of Telecommunications and Information Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A High-Efficient Low-Voltage Rectifier for CMOS Technology
Autorzy:
Jendernalik, W.
Jakusz, J.
Blakiewicz, G.
Kłosowski, M.
Powiązania:
https://bibliotekanauki.pl/articles/220356.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
CMOS rectifier
high frequency rectifier
wireless power transmission
Opis:
A new configuration of rectifier suiting CMOS technology is presented. The rectifier consists of only two n-channel MOS transistors, two capacitors and two resistors; for this reason it is very favourable in manufacturing in CMOS technology. With these features the rectifier is easy to design and cheap in production. Despite its simplicity, the rectifier has relatively good characteristics, the voltage and power efficiency, and bandwidth greater than 89%, 87%, and 1 GHz, respectively. The performed simulations and measurements of a prototype circuit fully confirmed its correct operation and advantages.
Źródło:
Metrology and Measurement Systems; 2016, 23, 2; 261-268
0860-8229
Pojawia się w:
Metrology and Measurement Systems
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A new methodology for designing and development of complex systems for high energy physics
Autorzy:
Makowski, D.
Powiązania:
https://bibliotekanauki.pl/articles/397800.pdf
Data publikacji:
2016
Wydawca:
Politechnika Łódzka. Wydział Mikroelektroniki i Informatyki
Tematy:
design methodology
high energy physics
large scale systems
electronic systems
AdvancedTCA
MicroTCA
reliability
availability
serviceability
low level radio frequency control system
image acquisition system
metodologia projektowania
fizyka wysokich energii
systemy wielkiej skali
układy elektroniczne
Advanced Telecommunications Computing Architecture
Micro Telecommunications Computing Architecture
niezawodność
gotowość
podatność obsługowa
radioelektroniczny niskopoziomowy system sterowania
akwizycja obrazów
Opis:
The paper describes a new methodology that allows to design scalable complex control and data acquisition systems taking into consideration the additional, non-functional requirements of High-Energy Physics (HEP). Electronic systems applied in HEP often operate in difficult conditions. Access to such devices is difficult or even impossible. The HEP systems require high availability, serviceability and upgradeability. The operating conditions of these systems are even more difficult than for telecommunication devices. Therefore, a different methodology should be applied than for classical telecommunication systems, when designing electronics used in high-energy physics applications. Electronic systems also need a suitable hardware platform that not only assures high availability, simplifies maintenance and servicing but also allows to use mixed analogue-digital signals. The author made an attempt to develop a new methodology suitable for designing of complex data acquisition and control systems of HEP. The Low Level RF (LLRF) system of European Free Electron Laser (EXFEL) and Image Acquisition System (IAS) prototype developed for International Thermonuclear Experimental Reactor (ITER) tokamak are presented as examples of complex electronic systems that were designed according to the proposed methodology.
Źródło:
International Journal of Microelectronics and Computer Science; 2016, 7, 4; 123-132
2080-8755
2353-9607
Pojawia się w:
International Journal of Microelectronics and Computer Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A novel circuit topology of modified switched boost hybrid resonant inverter fitted induction heating equipment
Autorzy:
Bhattacharya, A.
Sit, K.
Sadhu, P. K.
Pal, N.
Powiązania:
https://bibliotekanauki.pl/articles/140770.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
modified switched boost
high frequency
hybrid resonant inverter
induction heating
controllability
VSI and PSIM
Opis:
A novel circuit topology of modified switched boost high frequency hybrid resonant inverter fitted induction heating equipment is presented in this paper for efficient induction heating. Recently, induction heating technique is becoming very popular for both domestic and industrial purposes because of its high energy efficiency and controllability. Generally in induction heating, a high frequency alternating magnetic field is required to induce the eddy currents in the work piece. High frequency resonant inverters are incorporated in induction heating equipment which produce a high frequency alternating magnetic field surrounding the coil. Previously this high frequency alternating magnetic field was produced by voltage source inverters. But VSIs have several demerits. So, in this paper, a new scheme of modified switched boost high frequency hybrid resonant inverter fitted induction heating equipment has been depicted which enhances the energy efficiency and controllability and the same is validated by PSIM.
Źródło:
Archives of Electrical Engineering; 2016, 65, 4; 815-826
1427-4221
2300-2506
Pojawia się w:
Archives of Electrical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A novel method for separability of signal components to estimate radiation from a high-frequency subsystem
Autorzy:
Daneshvar, Milad
Parhizgar, Naser
Oraizi, Homayoon
Powiązania:
https://bibliotekanauki.pl/articles/140523.pdf
Data publikacji:
2019
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
electromagnetic interference
electromagnetic radiation
parameter estimation
multi-component signals
frequency response
radio frequency
Opis:
Specific requirements are designed and implemented in electronic and telecommunication systems for received signals, especially high-frequency ones, to examine and control the signal radiation. However, as a serious drawback, no special requirements are considered for the transmitted signals from a subsystem. Different industries have always been struggling with electromagnetic interferences affecting their electronic and telecommunication systems and imposing significant costs. It is thus necessary to specifically investigate this problem as every device is continuously exposed to interferences. Signal processing allows for the decomposition of a signal to its different components to simulate each component. Radiation control has its specific complexities in systems, requiring necessary measures from the very beginning of the design. This study attempted to determine the highest radiation from a subsystem by estimating the radiation fields. The study goal was to investigate the level of radiations received and transmitted from the adjacent systems, respectively, and present methods for control and eliminate the existing radiations. The proposed approach employs an algorithm which is based on multi-component signals, defect, and the radiation shield used in the subsystem. The algorithm flowchart focuses on the separation and of signal components and electromagnetic interference reduction. In this algorithm, the detection process is carried out at the bounds of each component, after which the separation process is performed in the vicinity of the different bounds. The proposed method works based on the Fourier transform of impulse functions for signal components decomposition that was employed to develop an algorithm for separation of the components of the signals input to the subsystem.
Źródło:
Archives of Electrical Engineering; 2019, 68, 3; 497-510
1427-4221
2300-2506
Pojawia się w:
Archives of Electrical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A Precise and High Speed Charge-Pump PLL Model Based on SystemC/SystemC-AMS
Autorzy:
Ma, K.
Van Leuken, R.
Vidojkovic, M.
Romme, J.
Rampu, S.
Pflug, H.
Huang, L.
Dolmans, G.
Powiązania:
https://bibliotekanauki.pl/articles/227120.pdf
Data publikacji:
2012
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
SystemC/SystemC-AMS
phase locked loop PLL
radio frequency
mixed-signal modeling
hardware description language
Opis:
The Phase Locked Loop (PLL) has become an important part of electrical systems. When designing a PLL, an efficient and reliable simulation platform for system evaluation is needed. However, the closed loop simulation of a PLL is time consuming. To address this problem, in this paper, a new PLL model containing both digital and analog parts based on SystemC/SystemC-AMS (BETA version) is presented. Many imperfections such as Voltage Control Oscillator (VCO) noise or reference jitter are included in this model. By comparing with the Matlab model, the SystemC/SystemC-AMS model can dramatically reduce simulation time. Also, by comparing with Analog Devices ADI SimPLL simulation results, Cadence simulation results and real measurement results, the accuracy of the SystemC/SystemC-AMS model is demonstrated. The paper shows the feasibility of a unified design environment for mixed-signal modelling based on SystemC/SystemC-AMS in order to reduce the cost and design time of electrical systems.
Źródło:
International Journal of Electronics and Telecommunications; 2012, 58, 3; 225-232
2300-1933
Pojawia się w:
International Journal of Electronics and Telecommunications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Adaptively Selecting Working Frequency to Reduce Disturbances in High Frequency Radar
Autorzy:
Gui, R.
Powiązania:
https://bibliotekanauki.pl/articles/1505197.pdf
Data publikacji:
2011-04
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
84.40.Xb
Opis:
In high frequency radar, we should avoid noise disturbances in the radar's working-frequency segment. Moreover, the sidelobes of strong targets interfere with the detection of weak targets. A new method based on an adaptive selecting working-frequency is proposed. Frequency spectrum monitor is designed for selecting quiet frequency segment for the radar. Frequency spectrum monitor and the receiver of the radar are arranged to work according to special time periods respectively. So the radar can work in the frequency segments with lower noise disturbances. Moreover, there is no correlation between the noise and the useful echo signal, though the correlation between noises over very short time periods is strong, the noise data produced by frequency spectrum monitor can be exploited effectively. Adjusting system parameters in real-time by adaptive methods can be utilized to reduce noise disturbances. Algorithm based on the properties of crosscorrelation between noise and target is exploited for suppressing sidelobe disturbances of strong targets. Lastly, the feasibility of the methods is verified by processing actual radar data.
Źródło:
Acta Physica Polonica A; 2011, 119, 4; 473-478
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
An accurate prediction of high-frequency circuit behaviour
Autorzy:
Yoshitomi, S.
Kimijima, H.
Kojima, K.
Kokatsu, H.
Powiązania:
https://bibliotekanauki.pl/articles/308807.pdf
Data publikacji:
2005
Wydawca:
Instytut Łączności - Państwowy Instytut Badawczy
Tematy:
electro-magnetic simulation
SPICE
circuit test structure
RF CMOS
EKV2.6-MOS model
spiral inductor
CMOS VCO
Opis:
An accurate way to predict the behaviour of an RF analogue circuit is presented. A lot of effort is required to eliminate the inaccuracies that may generate the deviation between simulation and measurement. Efficient use of computer-aided design and incorporation of as many physical effects as possible overcomes this problem. Improvement of transistor modelling is essential, but there are many other unsolved problems affecting the accuracy of RF analogue circuit modelling. In this paper, the way of selection of accurate transistor model and the extraction of parasitic elements from the physical layout, as well as implementation to the circuit simulation will be presented using two CMOS circuit examples: an amplifier and a voltage controlled oscillator (VCO). New simulation technique, electro-magnetic (EM)-co-simulation is introduced.
Źródło:
Journal of Telecommunications and Information Technology; 2005, 1; 47-62
1509-4553
1899-8852
Pojawia się w:
Journal of Telecommunications and Information Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
An analysis of the performance of genetic programming for realised volatility forecasting
Autorzy:
Yin, Z.
O’Sullivan, C.
Brabazon, A.
Powiązania:
https://bibliotekanauki.pl/articles/91765.pdf
Data publikacji:
2016
Wydawca:
Społeczna Akademia Nauk w Łodzi. Polskie Towarzystwo Sieci Neuronowych
Tematy:
realised volatility
genetic programming
high frequency data
Opis:
Traditionally, the volatility of daily returns in financial markets is modeled autoregressively using a time-series of lagged information. These autoregressive models exploit stylised empirical properties of volatility such as strong persistence, mean reversion and asymmetric dependence on lagged returns. While these methods can produce good forecasts, the approach is in essence atheoretical as it provides no insight into the nature of the causal factors and how they affect volatility. Many plausible explanatory variables relating market conditions and volatility have been identified in various studies but despite the volume of research, we lack a clear theoretical framework that links these factors together. This setting of a theory-weak environment suggests a useful role for powerful model induction methodologies such as Genetic Programming (GP). This study forecasts one-day ahead realised volatility (RV) using a GP methodology that incorporates information on market conditions including trading volume, number of transactions, bid-ask spread, average trading duration (waiting time between trades) and implied volatility. The forecasting performance from the evolved GP models is found to be significantly better than those numbers of benchmark forecasting models drawn from the finance literature, namely, the heterogeneous autoregressive (HAR) model, the generalized autoregressive conditional heteroscedasticity (GARCH) model, and a stepwise linear regression model (SR). Given the practical importance of improved forecasting performance for realised volatility this result is of significance for practitioners in financial markets.
Źródło:
Journal of Artificial Intelligence and Soft Computing Research; 2016, 6, 3; 155-172
2083-2567
2449-6499
Pojawia się w:
Journal of Artificial Intelligence and Soft Computing Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
An approach to suppress high-frequency resonance using model predictive and selective harmonic elimination combined strategy
Autorzy:
Chen, Sitong
Chen, Xiaoqiang
Wang, Ying
Xiong, Ye
Powiązania:
https://bibliotekanauki.pl/articles/1841300.pdf
Data publikacji:
2021
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
CRH5 EMUs and traction power supply coupled system
high-frequency oscillation
high speed railway
model predictive control (MPC)
selective harmonic elimination pulse-width modulation (SHEPWM)
CRH5 EMU i system sprzężony z zasilaniem trakcyjnym
oscylacja wysokiej częstotliwości
kolej dużych prędkości
kontrola predykcyjna modelu (MPC)
selektywna eliminacja harmoniczna modulacja szerokości impulsu (SHEPWM)
Opis:
High-frequency resonance is a prominent phenomenon which affects the normal operation of the high-speed railway in China. Aiming at this problem, the resonance mechanism is analyzed first. Then, model predictive control and selective harmonic elimination pulse-width modulation (MPC-SHEPWM) combined control strategy is proposed, where the harmonics which cause the resonance can be eliminated at the harmonic source. Besides, the MPC is combined to make the current track the reference in transients. The proposed control has the ability to suppress the resonance while has a faster dynamic performance comparing with SHEPWM. Finally, the proposed MPC-SHEPWM is tested in a simulation model of CRH5 (Chinese Railway High-speed), EMUs (electric multiple units) and a traction power supply coupled system, which shows that the proposed MPC-SHEPWM approach can achieve the resonance suppression and shows a better dynamic performance.
Źródło:
Archives of Electrical Engineering; 2021, 70, 2; 415-430
1427-4221
2300-2506
Pojawia się w:
Archives of Electrical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
An Insight into Coherent Backscattering Evaluation Techniques of Prospective Use in High Frequency Polarimetric Radar Image Processing
Autorzy:
Kapelewski, J.
Powiązania:
https://bibliotekanauki.pl/articles/1506794.pdf
Data publikacji:
2010-12
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
41.20.Jb
03.50.De
Opis:
Coherence in multiple scattering is important as it applies to imaging and detection of object in multiple scattering environments. These phenomena may also be used to investigate images of objects obscured by them. The scattering observations using very rough surfaces can provide useful insight into their statistic as they lie outside the range of validity of the standard theories. Recently, there has been growing interest in the phenomenon of backscattering enhancement in the reflection of electromagnetic waves of mm wave range from both atmospheric hydrometeors (rain, snow and precipitation) as well as very rough surfaces (including that of sea and terrain sea). Strong backscattering enhancement of mm waves incident at different incident angles, both in the TE and TM polarizations, was observed experimentally. In the paper a short description of specific techniques used for treating image processing of strongly irregular media is shortly presented. An emphasis is placed on the phenomena of interest in advanced polarimetric radar especially in mm wave range.
Źródło:
Acta Physica Polonica A; 2010, 118, 6; 1161-1167
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Analiza wpływu pęknięcia podstawy zęba obciążanego dużą siłą dynamiczną na zmiany rozkładu czasowo-częstotliwościowego sygnału WA
The influence of crack of high loads tooth on time - frequency distributions of vibroacoustical signal
Autorzy:
Wojnar, G.
Powiązania:
https://bibliotekanauki.pl/articles/328814.pdf
Data publikacji:
2006
Wydawca:
Polska Akademia Nauk. Polskie Towarzystwo Diagnostyki Technicznej PAN
Tematy:
przekładnia zębata
pęknięcie
uszkodzenie zęba
transformata Wignera-Ville'a
gear
crack
root tooth
tooth damage
Wigner-Ville analysis
Opis:
Bazując na zidentyfikowanym modelu dynamicznym przekładni zębatej w układzie napędowym przeprowadzono analizę wpływu odchyłek wykonania kół zębatych na siły dynamiczne działające na poszczególne zęby zębnika i koła. Określono przypadki, w których odchyłki te powodują największy wzrost wartości sił międzyzębnych. Duża siła dynamiczna działająca na ząb może być jedną z przyczyn powstania pęknięcia jego podstawy. W niniejszej pracy przedstawiono istotne różnice w zmianach rozkładu czasowo-częstotliwościowego sygnału resztkowego w przypadku symulowania pęknięcia podstawy mocno obciążanego zęba zębnika obarczonego niekorzystnymi odchyłkami wykonania i losowo wybranego zęba zębnika.
The large dynamic force in meshing is ones of causes of root tooth crack beginning. The identified model of power transmission system with toothed gear was used to determination of the influence of performance deviation on the dynamic forces in meshing. This paper presents essential differences in time - frequency distributions of residual signal in cases of crack simulation of high loads pinion tooth and random pinion tooth.
Źródło:
Diagnostyka; 2006, 1(37); 135-139
1641-6414
2449-5220
Pojawia się w:
Diagnostyka
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Analysis of circuit and operation for DC–DC converter based on silicon carbide
Autorzy:
Niewiara, Ł. J.
Tarczewski, T.
Grzesiak, L. M.
Powiązania:
https://bibliotekanauki.pl/articles/97287.pdf
Data publikacji:
2016
Wydawca:
Politechnika Poznańska. Wydawnictwo Politechniki Poznańskiej
Tematy:
DC\DC converter
SiC MOSFETS
high switching frequency
DC–DC converter design
snubber circuit
Opis:
In this paper operating analysis of DC–DC converter is presented. Silicon Carbide based DC–DC converter is investigated. SiC power switches (i.e. MOSFETs and diodes) were used. Synchronous buck topology is applied for converter structure. The DC–DC converter mathematical model is also presented. The parameters of LC circuit were calculated using shown equations. Working conditions determine the values of output LC circuit (inductance and capacitance). Real power semiconductors are equipped in output and input capacitances. This feature may influence the generated input signal. Parasitic capacitances and inductances of the paths causes oscillations and voltage overshoots of the input PWM signal. To avoid such phenomenon, it is necessary to use a snubber circuit. This issue is also presented. The analysis of working conditions is presented for different switching frequencies. The size of passive components (LC) is compared for different operating points. Experimental tests results were presented. Waveforms of voltage and current signals were also shown.
Źródło:
Computer Applications in Electrical Engineering; 2016, 14; 268-279
1508-4248
Pojawia się w:
Computer Applications in Electrical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Wyświetlanie 1-15 z 237

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