An approach to develop space solar power as a new energy system for developing countries

The idea of space solar power proposed by Glaser was explained as a set of a solar power power station in geostationary earth orbit to transmit microwave power and a ground station to receive the microwave power. Most of the ideas and concepts since Glaser used the same context. On the other hand, Collins et al. (Proceedings SPS '91, pp. 132–141, 1991) introduced the concept of microwave “fuel” to assess the commercial relations of power from space, in which space solar power stations are considered to sell microwave power to any unspecified rectenna. This concept changed the theoretical context of “power from space” to an industrial and economic relation of producers and buyers of an industrial product. This new context has been applied to the SPS 2000 conceptual study. As a result, if 2.45 GHz microwave power transmission is used, each rectenna can be planned and engineered independently from the space sector by local users, especially in developing countries, who are familiar with such activities as introducing solar energy systems.     

On the way to creating a system of distant power supply for space vehicles

Using power resources of the outer space and its industrialization have become an urgent task in the development of present day civilization. Solar energy is the most suitable basis for power supply for the majority of projects in the near-Earth space. Passing on to the large-scale space-based systems of power supply requires putting into life demonstration experiments in which power transmission by electromagnetic emission is supposed.In the paper the expedience of developing an autonomous power module which provides the possibility of space programs with great power consumption and wireless transmission system running-up is proved. Ukraine can design a solar power satellite of 10–20 kW power on the basis of the research satellite AUOS-SM. Two variants of design solutions for such satellite with solar arrays of great area are presented. Power transmission to the space vehicle-consumer can be conducted by cable as well as in a wireless way. The possibilities of placing microwave and laser energy transmission systems on board the satellite are analysed. It is shown that a power supply system for space vehicles with transmission distance of thousands km can be designed basing on modern lasers.Some experiments making use of great electric power generated by the plant of the satellite under consideration are proposed. The running-up of electric thrusters which are necessary for orientation and distancing is of great interest. Wireless power transmission may be carried on to a small satellite equipped with electric thrusters.     

Microwave pre-curing of natural rubber-compounding using a rectangular wave guide

This article presents a new method to pre-cure natural rubber-compounding (NRc) by using microwave energy at a frequency of 2.45 GHz with a rectangular wave guide. The influences of microwave power input, specimen thicknesses, and vulcanized sulfur contents on the dielectric and thermal characteristics and cross-linked contents of microwave-cured NRc are studied. Furthermore, a generalized mathematical model for predicting temperature distribution inside the specimen during pre-heating is proposed. Significant results show that microwave energy can produce partial cross-linking at temperatures below the actual vulcanizing process. The numerical results from the model agree well with the results from the experiments.     

Preparation of TiO2 nanocrystalline electrode for dye-sensitized solar cells by 28 GHz microwave irradiation

Microwave preparation of TiO₂ nanocrystalline electrode for use in dye-sensitized solar cells is examined. A multi-mode microwave heating system operating at a frequency of 28 GHz is used to produce rapid processing. Well-sintered TiO₂ nanocrystalline thin film is successfully fabricated on transparent conductive FTO glass electrode. Photoelectron energy conversion efficiency of 5.51% is achieved in an electrode prepared by 28 GHz microwave irradiation at 0.7 kW for 5 min.     

节能新技术在远距离管网温度监测系统的应用

大庆石化公司对其外送输油管道伴热管线进行温度监测,采用了基于GPRS的通讯和太阳能供电技术,该温度监测系统由监测中心、监测终端、通讯网络三部分组成,其中监测终端采用太阳能系统供电。采用GPRS无线数传技术,信号传输速度快、稳定性好、抗干扰能力强;采用高精度的E型表面热电偶和Adam 4018+工业级智能温度采集模块,准确性好、故障率低;采用太阳能供电,具有防燃、防爆、耐高压等多种特性,安全性好;软件系统功能丰富,可以设置多点报警和在线修改报警界限值,灵活性高;本系统模块化程度高,使用元器件综合考虑了使用寿命和维护成本,维护方便、扩展性强、性价比高;为监测终端设计了保温箱,提高了系统的抗寒能力。从系统运行情况来看,各监测终端与监测中心的通信稳定,中心软件运行正常,各项指标均满足要求。GPRS通讯和太阳能供电系统,与传统的温度检测系统相比,减少了电缆及其铺设费用,减少了电费消耗。本技术具有推广价值。     

Atmospheric pressure microwave plasma source for hydrogen production

Nowadays hydrogen is considered as a clean energy carrier and fuel of the future. That is why the interest in production and storage of hydrogen is still increasing. One of the promising technology is using microwave plasma for hydrogen production. In this study we propose two types of an atmospheric pressure microwave plasma source (MPS) for hydrogen production via methane conversion. The first one was a nozzleless waveguide-supplied coaxial-line-based. The second one was a nozzleless waveguide-supplied metal-cylinder-based. They can be operated with microwave frequency of 2.45 GHz and power up to a few kW with a high gas flow rates (up to several thousands l/h). We present experimental results concerning electrical properties of the MPS, plasma visualization, spectroscopic diagnostics and hydrogen production. The experiment was carried out with methane flow rate up to 12,000 l/h. An additional nitrogen or carbon dioxide swirl flow was used. The absorbed microwave power was up to 5000 W. Our experiments show that MPSs presented in this paper have a high potential for hydrogen production via hydrocarbon conversion.     

Experimental validation of local thermal equilibrium in a MW plasma torch for hydrogen production

In this paper, experimental and numerical studies are made to investigate local thermal equilibrium in a microwave plasma torch at atmospheric pressure for hydrogen and carbon black production from methane dissociation. The microwave induced plasma can be operated up to 2 kW power at 2.45 GHz frequency. Methane is dissociated in argon, air or nitrogen plasma and optical emission spectroscopy is used to characterize the plasma. C₂, CN and OH ro-vibrational bands are used for rotational and vibrational temperature estimation while stark broadening of H-line is used for electron temperature calculation. Temperatures are determined at varying operating parameters of microwave power, axial gas flow rate, and methane flow rate. The rotational (heavy particle), vibrational, and electron temperatures are found to be equal to 5000 ± 500 K. The plasma is thus at local thermodynamic equilibrium.     

The role of pilot projects and public acceptance in developing wireless power transmission as an enabling technology for space solar power systems

In all system concepts for delivering space solar power to terrestrial power systems, wireless power transmission (WPT) is identified as a critical link in the technology chain. To realize the full potential of WPT as an enabling technology for the development of space power systems, the technology needs to (1) be demonstrated as a commercially viable, low risk technology and (2) be shown to be acceptable to the public. If WPT's full potential is to be realized, its initial applications must be carefully chosen and demonstrated through a series of pilot projects which will develop both the technology and its public acceptance.This paper examines the role of pilot projects and how they will play an increasingly important role in the development and acceptance of WPT as an enabling technology for space solar power systems. Recognizing that public acceptance is the ultimate determinant of the commercial success or failure of a technology, the paper then explores the role of public opinion in the commercialization process of space solar power systems utilizing WPT. A framework that begins to define the process required to realize the full commercial potential of wireless power transmission is established.     

基于无线高速数据传输的智能燃料管理应用方案研究

[目的]目前国内火电行业的智能燃料管理系统中还是使用较为传统的线路传输技术,无论是对于数据的整合处理还是与智能一体化管控云平台互联均欠缺灵活性、可靠性、移动性.数据通讯是电厂管理智能化的重要发展趋势,而更高速的传输速率更是未来智能电厂大数据云计算平台所需建设的目标.为研究更高速的无线数据传输在电力行业应用,将目前最新的...     

共振磁耦合无线电能传输系统参数与电磁分布特性仿真研究

为进一步改进共振磁耦合式无线充电系统的低频化问题,利用二端口网络参数理论对共振磁耦合无线电能传输系统进行建模,分析了系统传输效率与功率和S参数的关系,指出传输效率最大化的条件,提出了降低无线电能传输系统工作频率的必要性,并结合低频化设计思路,针对铜贴片改变进行HFSS本征频率仿真,得到系统共振频率和贴片厚度、距离、摆放位置等之间的关联,基于仿真结果为共振线圈选择合适的品质因数和共振频率。最后针对典型的共振磁耦合传输系统传输通道上的电磁场分布特性进行计算,得到磁场强度分布,比较了加入屏蔽体之后对传输系统的性能影响和屏蔽体效果,提高了系统传输效率。     

Experimental study of the performance of a solar thermal-photovoltaic integrated system

In this work a self-contained solar heating forced water cooling unit was selected and assembled. It consists of three flat-plate solar collectors, each of area 1.2 m², a.d.c. pump, a photovoltaic module and a storage tank. The electrical power produced by the photovoltaic module operates the d.c. pump, which circulates the cooling water through the solar collectors to transfer the heat to the storage tank. The electrical voltage and current, the water rate of flow, and water temperature at inlet and outlet of the collector were all measured. Solar irradiation, wind speed and ambient temperature were also measured. Daily distribution of electrical current, water mass rate of flow, module efficiency and collector efficiency were plotted in figures. Module efficiency, pump efficiency and collector efficiency were taken as dependent variables, while the solar irradiation, ambient temperature and time were the independent variables. Optimum values were graphically indicated and related to each other in a clear discussion. An economic study and comparison of three different systems were carried out: a common thermosyphon system; an a.c. pump circulating system; and this system, which is a d.c. pump circulating system. Results revealed that collector efficiency reached a daily average value of 47% due to d.c. pump installation powered by photovoltaic electric output.     

Electrowetting-on-Dielectric by Wireless Powering

Electrowetting-on-dielectric (EWOD), in which microdroplets are manipulated using electrical inputs, has drawn a great deal of attraction with applications of digital lab-on-a-chip and hot-spot cooling. In most EWOD actuations, the commonly used powering method is wired transmission, which may not be suitable for isolating and employing EWOD devices in hard-to-reach areas. In this study, we investigate wireless power transmission for EWOD utilizing inductive coupling. Since EWOD is typically operated by a high-input voltage although the current is minimal, wireless EWOD also requires a similarly high voltage at the receiver, unlike conventional inductive coupling. To meet this condition, the resonant inductive coupling method at a high resonant frequency is introduced and investigated. To optimize the transmission efficiency, we study the effects of many parameters, such as the frequency, inductance, and capacitance at the transmitter and receiver, the gap between the transmitter coil and receiver coil, and the droplet size, by measuring the voltage at the receiver and the contact angle of the droplet placed on a wirelessly operated EWOD chip. In addition, by applying amplitude modulation to the resonant inductive coupling, wireless AC-EWOD, which generates droplet oscillations and is a common mode for EWOD droplet handling, is also achieved. Finally, it is successfully demonstrated that a droplet is transported laterally by using an array of electrodes, which is also powered by an amplitude-modulated wireless signal.     

Application of atmospheric pressure microwave plasma source for hydrogen production from ethanol

In contrast to conventional technologies of hydrogen production like water electrolysis or coal gasification we propose a method based on the atmospheric pressure microwave plasma. In this paper we present results of the experimental investigations of the hydrogen production from ethanol in the atmospheric pressure plasma generated in waveguide-supplied cylindrical type nozzleless microwave (915 MHz and 2.45 GHz) plasma source (MPS). Argon, nitrogen and carbon dioxide were used as a working gas. All experimental tests were performed with the working gas flow rate Q ranged from 1500 to 3900 NL/h and absorbed microwave power P_A up to 6 kW. Ethanol was introduced into the plasma as vapours carried with the working gas. The process resulted in the ethanol conversion rate greater than 99%. The hydrogen production rate was up to 210 NL[H₂]/h and the energy efficiency was 77 NL[H₂] per kWh of absorbed microwave energy.     

基于ZigBee的电能信息数据通信方法

ZigBee是一种基于IEEE802.15.4标准指定的短距离、低功耗的无线通信技术,具有低复杂度、自组织、低功耗、低成本的特点,可以灵活地结合嵌入式技术并广泛应用于自动控制领域。文章针对电能信息采集的数据通信需求,对基于ZigBee通信的电能信息采集系统中采集终端与采集主站之间的电能信息数据传输方法进行了研究,给出了传输规则、应用协议单元协议的制定方法以及基于STM32F407与CC2530的采集终端的软硬件设计。实验证明通信稳定可靠,电能信息数据的传输效率得到了提高。     

Numerical analysis of microwave melting of ice-saturated porous medium filled in a rectangular waveguide with resonator using a combined transfinite interpolation and PDE methods

A numerical study is performed for the melting process of ice-saturated porous medium filled in a rectangular waveguide with a resonator subjected to electromagnetic energy. A microwave system supplies a monochromatic wave in a fundamental mode (TE₁₀ mode) with operating frequency of 2.45 GHz. Focus is placed on establishing a computationally efficient approach for solving moving boundary heat transfer problem in a two-dimensional structured grid. Numerically, preliminary grids are first generated by an algebraic method, based on a transfinite interpolation method, with subsequent refinement using a PDE mapping method. A preliminary case study indicates successful implementation of the numerical procedure. The predicted results from two-dimensional melting model are then validated against available experimental results and subsequently used as a tool for efficient computational prototyping. Based on the numerical results are performed illustrating the influence of resonator and layered configuration, in case of the installed resonator has strongly affected on the microwave power absorbed, temperature distribution, and the melting front during microwave melting process.     

New battery technologies and their potential impact in the use of energy in the telephone industry

The principal use of batteries in the telecommunications industry is to provide standby or emergency d.c. power to telephone exchanges in the event of a failure or breakdown in the utility supply. Batteries are also used for standby power in microwave relay stations, for emergency lighting, and a variety of other minor uses.Due to its low cost, long life and reliability the lead-acid battery dominates standby applications. Substantial developments are, however, in progress throughout the world to develop secondary batteries for use in electric vehicles and utility load-leveling. In addition, substantial improvements are being made in the development of compact, low-cost primary batteries such as those based on zinc-air and lithium technology.The characteristics of the lead-acid and nickel-cadmium systems are reviewed and the systems under development are then described together with their predicted characteristics and costs. The possible impact on the telecommunications industry of these new developments in battery technology is discussed.     

An experimental study of syn-gas production via microwave plasma reforming of methane,iso-octane and gasoline

A newly developed microwave plasma system for fuel reforming was tested for three different hydrocarbon fuels. The microwave plasma system was powered by a low cost commercial magnetron and power supply. The microwave power was delivered to the nozzle from the magnetron via a coaxial cable, which offers tremendous flexibility for system design and applications. A non-premixed configuration was achieved by delivering a separate stream of fuel to the plasma plume, which is composed of diluted oxygen only. The feasibility of syn-gas production capability of the microwave plasma system was demonstrated and the reforming characteristics of methane, iso-octane and gasoline were compared. The effects of input power, injected fuel amount, total flow rate and O/C ratio were evaluated. The production rates of both hydrogen and carbon monoxide were proportional to the input power and the inverse of the total flow rate. As a result, the maximum efficiency of 3.12% was obtained with iso-octane for power consumption of 28.8 W, O/C ratio of 1, and 0.1 g/min of fuel supply. Liquid fuels produced more syn-gas and showed better efficiency than methane for the same input powers and O/C ratios.     

远程电力数据信息采集系统研究

针对永安市中小水电、开闭所和部分配电台区的信息采集和传输难题,利用无线移动通信技术(GPRS/CDMA)实现水电站远程电力数据的采集,为电网安全运行提供实时、准确的数据.运行结果表明,该系统可用于任何移动通信信号覆盖范围内的远距离信号的采集、测量和传输,具有较高的实用价值.     

高效率微波输电微带贴片接收整流天线的研究与设计

针对常用设计原理和方法的不足,引入一种新的设计原理,降低了系统的实现难度,提高了系统的整流效率,设计了一个2.45GHz的矩形微带贴片接收整流天线,仿真结果表明系统的总体转换效率达84％,证明了该设计原理的可行性和高效性。     

Theoretical and experimental investigation of microwave thawing of frozen layer using a microwave oven (effects of layered configurations and layer thickness)

The thawing of layered sample due to microwave energy (2.45 GHz) in oven has been investigated theoretically and experimentally. Based on a model combining of the electromagnetic field and thermal model, it is shown that the variation of layered configurations and unfrozen layer thickness changes the degree of temperature level within layered sample as well as the thawing rate. This is due to the changing of characteristics of dielectric properties of phase change materials during microwave thawing process. The simulated results are in agreement with the experimental results for the microwave thawing process.