Metal (M = Co, Ni) phosphate based materials for high-performance supercapacitors

2018 ◽  
Vol 5 (1) ◽  
pp. 11-28 ◽  
Author(s):  
Xinran Li ◽  
Xiao Xiao ◽  
Qing Li ◽  
Jilei Wei ◽  
Huaiguo Xue ◽  
...  

With the ever increasing demand for clean, sustainable energy, electrochemical supercapacitors with the advantages of high power density, high efficiency and long life expectancy have become one of the major devices for energy storage and power supply, and have found wide application in hybrid power sources, backup power sources, starting power for fuel cells and burst-power generation in electronic devices.

Author(s):  
Sheng Kang ◽  
Guofeng Chen ◽  
Chun Wang ◽  
Ruiquan Ding ◽  
Jiajun Zhang ◽  
...  

With the advent of big data and cloud computing solutions, enterprise demand for servers is increasing. There is especially high growth for Intel based x86 server platforms. Today’s datacenters are in constant pursuit of high performance/high availability computing solutions coupled with low power consumption and low heat generation and the ability to manage all of this through advanced telemetry data gathering. This paper showcases one such solution of an updated rack and server architecture that promises such improvements. The ability to manage server and data center power consumption and cooling more completely is critical in effectively managing datacenter costs and reducing the PUE in the data center. Traditional Intel based 1U and 2U form factor servers have existed in the data center for decades. These general purpose x86 server designs by the major OEM’s are, for all practical purposes, very similar in their power consumption and thermal output. Power supplies and thermal designs for server in the past have not been optimized for high efficiency. In addition, IT managers need to know more information about servers in order to optimize data center cooling and power use, an improved server/rack design needs to be built to take advantage of more efficient power supplies or PDU’s and more efficient means of cooling server compute resources than from traditional internal server fans. This is the constant pursuit of corporations looking at new ways to improving efficiency and gaining a competitive advantage. A new way to optimize power consumption and improve cooling is a complete redesign of the traditional server rack. Extracting internal server power supplies and server fans and centralizing these within the rack aims to achieve this goal. This type of design achieves an entirely new low power target by utilizing centralized, high efficiency PDU’s that power all servers within the rack. Cooling is improved by also utilizing large efficient rack based fans for airflow to all servers. Also, opening up the server design is to allow greater airflow across server components for improved cooling. This centralized power supply breaks through the traditional server power limits. Rack based PDU’s can adjust the power efficiency to a more optimum point. Combine this with the use of online + offline modes within one single power supply. Cold backup makes data center power to achieve optimal power efficiency. In addition, unifying the mechanical structure and thermal definitions within the rack solution for server cooling and PSU information allows IT to collect all server power and thermal information centrally for improved ease in analyzing and processing.


2021 ◽  
Vol 335 ◽  
pp. 02007
Author(s):  
Gowthamraj Rajendran ◽  
Chockalingam Aravind Vaithilingam ◽  
Kanendra Naidu ◽  
Kameswara Satya Prakash ◽  
Md Rishad Ahmed

Wide bandgap (WBG) semiconductors offer better switching and lower losses, and it is not uncommon to utilize them for high power density, high-efficiency applications. Gallium nitride (GaN) and Silicon carbide (SiC) are the most common WBG materials that are responsible for major switching level changes relative to silicon (Si) devices. This paper explores the contrast of performance between Si, SiC, and GaN devices. The output performance of Si, SiC, and GaN power devices includes efficiency, energy bandgap, thermal conductivity, carrier mobility, saturation speed, power density, switching characteristics, and conduction losses. This article also proposes a Vienna rectifier with GaN materials, which operates as a front-end rectifier on a high-density battery charger targeted at high-performance applications such as electric vehicle charging stations, aircraft applications, and welding power sources. The system would reduce the total harmonics distortion (THD) to less than 5%, and the power factor would be increased to unity to satisfy the IEEE-519 standard.


Sensors ◽  
2020 ◽  
Vol 20 (21) ◽  
pp. 6309
Author(s):  
Miroslav Popela ◽  
Jan Leuchter ◽  
Jana Olivová ◽  
Marie Richterová

This paper describes the design and construction of a remotely controlled mobile interference device designed primarily for interference (jamming) and immunity testing of wireless sensors operating in the 2.4 GHz band (Wi-Fi). The main idea was to build a remotely controlled test device to test the immunity of wireless sensors operating in the 2.4 GHz band directly in field conditions. The remotely controlled mobile interference device is equipped with a special interference apparatus, using a special magnetron tube as a source of interference. Magnetron was selected due to its high performance, allowing interference with wireless sensors over long distances. As magnetron is powered by high voltage (3 kVDC) and is being used in a remotely controlled device, it was important to solve the issue of its power supply using an accumulator. The remotely controlled device was further equipped with the option of detecting and analysing signals in the frequency band of 1 GHz to 18 GHz, adding an extra operational mode that can be used in civil (commercial), industrial, and military applications. Detection and analysis of extraneous signals that may affect our various electronic devices, operating in the 1 GHz to 18 GHz frequency band, is very important. By detecting and analyzing the detected signal, it is possible to recognize what kind of foreign device is transmitting on the detected frequency and how much it can affect the proper functioning of our electronic devices. All the individual parts of the remotely controlled mobile interference device are described in this article in detail, including their optimization for maximum use of the accumulator capacity by which the remotely controlled mobile interference device is powered. A substantial part of this article is devoted to optimizing the interference apparatus power supply with a resonant converter and internal intelligence, where the accumulators’ capacity is measured to gain needed predictions for maximum use of Li-Po batteries and thus extending its time of use.


2012 ◽  
Vol 614-615 ◽  
pp. 1759-1765
Author(s):  
Yi Cheng Chen ◽  
Zhi Xin Wang

This article aims to make a design of the power supply for an isolated island that has difficulty in realizing the connection with the mainland power grid. An independent hybrid power system consisting of varieties of renewable power sources including solar power, wind power, wave energy and batteries are introduced. This system is dedicated to make the forecast of the electricity load of the island according to the environmental factors and the electricity demand of the island. Then it builds the basic framework and models of hybrid power system on the basis of the forecast and finds out the appropriate method to optimize the power supply.


2013 ◽  
Vol 397-400 ◽  
pp. 1888-1892
Author(s):  
Qiu Yan Wang ◽  
Yan Liu ◽  
Ping Xu ◽  
Da Cheng Luo

The integrated half-bridge IGBT driver need compact, high efficiency and high power density isolated DC-DC power supply, a set of two magnetic cores share a high-frequency full-bridge switches are designed. A simple circuit generates four channel drive signals, without isolation, to achieve compact on-board power supply and the best combination with the integrated half-bridge IGBT driver. The key signals are simulated, and experimental results show that the power supply is simple, reliable.


2016 ◽  
Vol 4 (6) ◽  
pp. 2096-2104 ◽  
Author(s):  
Fei Li ◽  
Hao Chen ◽  
Xiao Ying Liu ◽  
Shi Jin Zhu ◽  
Jia Qi Jia ◽  
...  

The development of portable and wearable electronics has promoted the increasing demand for high-performance power sources with high energy/power density, low cost, lightweight, as well as ultrathin and flexible features.


Nanoscale ◽  
2021 ◽  
Author(s):  
Wei Cao ◽  
Yun Gong ◽  
Wenhao Wang ◽  
Mingzhou Chen ◽  
Junhe Yang ◽  
...  

Fiber-shaped supercapacitors (FSCs) are promising power sources for wearable electronic devices due to their small size, excellent flexibility and deformability. The performance of FSCs has been severely affected by the...


2018 ◽  
Vol 20 (13) ◽  
pp. 8658-8667 ◽  
Author(s):  
Thao P. Nguyen ◽  
P. Roy ◽  
Ji Hoon Shim

A density functional theory (DFT) calculation predicts phenacene as one of the most promising organic semiconductors for high efficiency electronic devices.


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