High-frequency drive of high-Xe-content PDPs for high efficiency and low-voltage performance

2004 ◽  
Vol 12 (2) ◽  
pp. 191 ◽  
Author(s):  
Tetsuo Minami ◽  
Tomokazu Shiga ◽  
Shigeo Mikoshiba ◽  
Gerrit Oversluizen
Keyword(s):  
High Frequency ◽  
High Efficiency ◽  
Low Voltage ◽  
Voltage Performance

Design of a High Efficiency Fuel Cell dc/dc Converter Dedicated to Transportation Applications

2008 ◽  
Vol 5 (4) ◽  
Author(s):  
Abdellah Narjiss ◽  
Daniel Depernet ◽  
Frédéric Gustin ◽  
Daniel Hissel ◽  
Alain Berthon
Keyword(s):  
Fuel Cell ◽  
Embedded System ◽  
Digital Signal Processor ◽  
High Frequency ◽  
High Efficiency ◽  
Low Voltage ◽  
Electrical Power ◽  
Digital Signal ◽  
Polymer Electrolyte Fuel Cell ◽  
High Frequency Transformer

This work consists in a theoretical and practical study of a dc/dc converter designed to be coupled to a fuel cell stack in transport applications. It also proposes analysis and control of the whole system using digital signal processor (DSP) controller. The research is focused on the integration of a polymer electrolyte fuel cell (PEFC) stack in an embedded system. The fuel cell is characterized by a low-voltage high-current electrical power deliverty. Therefore, it is obvious that a dedicated power interface is necessary to adapt and fix voltage and current levels accordingly to the application requirements. In our case, the power conversion will be done by a high-frequency-transformer-based DC/DC converter. The use of a high frequency transformer allows obtaining significant output voltage ratio (approximately 12 in our case), high efficiency, reduce compactness of used elements and limited semi-conductors losses.

scholarly journals A Comparative Analysis of Half-Bridge LLC Resonant Converters Using Si and SiC MOSFETs

2021 ◽  
Vol 12 (1) ◽  
pp. 43
Author(s):  
Hasaan Farooq ◽  
Hassan Abdullah Khalid ◽  
Waleed Ali ◽  
Ismail Shahid
Keyword(s):  
Silicon Carbide ◽  
Renewable Energy ◽  
High Frequency ◽  
High Efficiency ◽  
Low Voltage ◽  
Low Cost ◽  
Renewable Energy Sources ◽  
Input Voltage ◽  
Resonant Converters ◽  
Wide Range

With the expansion of renewable energy sources worldwide, the need for developing more economical and more efficient converters that can operate on a high frequency with minimal switching and conduction losses has been increased. In power electronic converters, achieving high efficiency is one of the most challenging targets to achieve. The utilization of wideband switches can achieve this goal but add additional cost to the system. LLC resonant converters are widely used in different applications of renewable energy systems, i.e., PV, wind, hydro and geothermal, etc. This type of converter has more benefits than the other converters such as high electrical isolation, high power density, low EMI, and high efficiency. In this paper, a comparison between silicon carbide (SiC) MOSFET and silicon (Si) MOSFET switches was made, by considering a 3KW half-bridge LLC converter with a wide range of input voltage. The switching losses and conduction losses were analyzed through mathematical calculations, and their authenticity was validated with the help of software simulations in PSIM. The results show that silicon carbide (SiC) MOSFETs can work more efficiently, as compared with silicon (Si) MOSFETs in high-frequency power applications. However, in low-voltage and low-power applications, Si MOSFETs are still preferable due to their low-cost advantage.

Low-voltage alternating current powered polydopamine-protected copper phosphide nanowire for electroporation-disinfection in water

2019 ◽  
Vol 7 (13) ◽  
pp. 7347-7354 ◽  
Author(s):  
Zheng-Yang Huo ◽  
Hai Liu ◽  
Wen-Long Wang ◽  
Yun-Hong Wang ◽  
Yin-Hu Wu ◽  
...  
Keyword(s):  
High Frequency ◽  
High Efficiency ◽  
Low Voltage ◽  
Alternating Current ◽  
Continuous Operation ◽  
Copper Phosphide ◽  
High Frequency Ac

Powered by high-frequency AC, PDA-Cu3PNW-Cu electrodes enable complete microorganism disinfection in water with high efficiency for a 15 day continuous operation.

Method of high frequency therapy at cows' mastitis during machine milking

2020 ◽  
pp. 9-12
Author(s):  
Viktor E. Lyubimov ◽  
Keyword(s):  
Dairy Cows ◽  
Electromagnetic Fields ◽  
High Frequency ◽  
High Efficiency ◽  
Environmentally Friendly ◽  
Ultrahigh Frequency ◽  
Machine Milking ◽  
High Frequency Electromagnetic Field ◽  
Milking Machine ◽  
Methods Of Treatment

Health of dairy cows ensures human health, so it is important that dairy products do not contain antibiotics that are used to treat any inflammation, including mastitis. In Russia at present, the problem of mastitis in cows exists with both attached and loose housing of cows. Mastitis of dairy cows are the great problem in milking husbandry. Losses from mastitis in milk yield can reach 15-20%. The main reasons for the occurrence of nonspecific mastitis of cows are the shortcomings of the working components of the milking machine: the degree of deterioration of the nipple rubber and the violation of machine milking technology (the reduction in pre-milking time and vacuum fluctuations account for 70% of all causes). Treatment of mastitis with antibiotics is effective, but not environmentally friendly and unacceptable. For the treatment of inflammation of the udder, it is necessary to use more environmentally friendly methods of treatment, one of which is the exposure to ultra-high frequency electromagnetic field tested by medicine. Use of three types of medical-mobile milking machines with the same method of exposure to ultrahigh-frequency electromagnetic fields on cow's nipples through electrodes in milking cups: LPDA-1-UHF, LPDA-2-UHF and LPDA-UHF-30 M, is described in the article. Author proved that cows with subclinical forms of mastitis recovered faster during milking with exposure to the ultrahigh frequency than when treated by antibiotics, and milking with the ultrahigh frequency device helps to recover 82% of the affected quarters with clinical forms and 100% of cows with subclinical forms of mastitis or with udder irritation. The high efficiency of the method of exposure to electromagnetic fields of the ultrahigh frequency during machine milking by means of medical-mobile milking machines LPDA-UHF for the prevention and treatment of mastitis of cows was shown.

scholarly journals Novel High-Efficiency High Step-Up DC–DC Converter with Soft Switching and Low Component Voltage Stress for Photovoltaic System

Processes ◽  
2021 ◽  
Vol 9 (7) ◽  
pp. 1112
Author(s):  
Yu-En Wu ◽  
Jyun-Wei Wang
Keyword(s):  
High Voltage ◽  
Output Voltage ◽  
High Efficiency ◽  
Low Voltage ◽  
Leakage Inductance ◽  
Power Switch ◽  
Half Wave Voltage ◽  
Half Wave ◽  
Voltage Stress ◽  
Voltage Doubler

This study developed a novel, high-efficiency, high step-up DC–DC converter for photovoltaic (PV) systems. The converter can step-up the low output voltage of PV modules to the voltage level of the inverter and is used to feed into the grid. The converter can achieve a high step-up voltage through its architecture consisting of a three-winding coupled inductor common iron core on the low-voltage side and a half-wave voltage doubler circuit on the high-voltage side. The leakage inductance energy generated by the coupling inductor during the conversion process can be recovered by the capacitor on the low-voltage side to reduce the voltage surge on the power switch, which gives the power switch of the circuit a soft-switching effect. In addition, the half-wave voltage doubler circuit on the high-voltage side can recover the leakage inductance energy of the tertiary side and increase the output voltage. The advantages of the circuit are low loss, high efficiency, high conversion ratio, and low component voltage stress. Finally, a 500-W high step-up converter was experimentally tested to verify the feasibility and practicability of the proposed architecture. The results revealed that the highest efficiency of the circuit is 98%.

The Design of 5V/100W High Frequency Switching Power Supply

2013 ◽  
Vol 834-836 ◽  
pp. 1221-1224
Author(s):  
Hong Zhuan Cai ◽  
Li Bai
Keyword(s):  
Power Supply ◽  
High Frequency ◽  
High Efficiency ◽  
Design Method ◽  
Switching Power Supply ◽  
Widespread Application ◽  
Forward Converter ◽  
Switching Power ◽  
Dc Power ◽  
Important Field

Switching power supply is an important field of application of power electronic technology, the high frequency switching DC power supply with high efficiency, small size, light weight and other advantages obtain the widespread application. The application of synchronous rectifier technology, photoelectric coupling isolation technology and the active clamp forward converter design high frequency switching power supply with 16~40V DC input and 5V/100W DC output . its operational principle is analyzed, and using LM5026 control chip describes design method of switching power supply.

scholarly journals Distinct EEG seizure patterns reflect different seizure generation mechanisms

2015 ◽  
Vol 113 (7) ◽  
pp. 2840-2844 ◽  
Author(s):  
Pariya Salami ◽  
Maxime Lévesque ◽  
Jean Gotman ◽  
Massimo Avoli
Keyword(s):  
High Frequency ◽  
Channel Blocker ◽  
Seizure Activity ◽  
Low Voltage ◽  
High Frequency Oscillation ◽  
Seizure Onset ◽  
Frequency Oscillation ◽  
Oscillation Analysis ◽  
Pilocarpine Model ◽  
Generation Mechanisms

Low-voltage fast (LVF)- and hypersynchronous (HYP)-seizure onset patterns can be recognized in the EEG of epileptic animals and patients with temporal lobe epilepsy. Ripples (80–200 Hz) and fast ripples (250–500 Hz) have been linked to each pattern, with ripples predominating during LVF seizures and fast ripples predominating during HYP seizures in the rat pilocarpine model. This evidence led us to hypothesize that these two seizure-onset patterns reflect the contribution of neural networks with distinct transmitter signaling characteristics. Here, we tested this hypothesis by analyzing the seizure activity induced with the K+ channel blocker 4-aminopyridine (4AP, 4–5 mg/kg ip), which enhances both glutamatergic and GABAergic transmission, or the GABAA receptor antagonist picrotoxin (3–5 mg/kg ip); rats were implanted with electrodes in the hippocampus, the entorhinal cortex, and the subiculum. We found that LVF onset occurred in 82% of 4AP-induced seizures whereas seizures after picrotoxin were always HYP. In addition, high-frequency oscillation analysis revealed that 4AP-induced LVF seizures were associated with higher ripple rates compared with fast ripples ( P < 0.05), whereas picrotoxin-induced seizures contained higher rates of fast ripples compared with ripples ( P < 0.05). These results support the hypothesis that two distinct patterns of seizure onset result from different pathophysiological mechanisms.

Sign in / Sign up

Export Citation Format

Share Document