基于鲁棒优化的煤电能源供应链中长期风险减轻策略

旨在为煤电能源供应链风险管理提供一个以价值型绩效为基础的整体框架,以形成中长期风险降低策略。首先对供应链不确定性、供应链风险和鲁棒优化进行了全面分析,界定了供应链节点企业,指出实际管理中的"下行风险"是煤电能源供应链风险管理的重点。然后,以为基于价值的管理提供实用的决策支持为建模思路,建立了基于鲁棒优化的煤电能源供应链风险管理模型,并对基本模型、对等模型和决策模型进行了详细阐述。最后,通过算例和科学的量化指标,从方案鲁棒性、目标鲁棒性和信息鲁棒性3个方面讨论了模型的有效性。

基于Seebeck效应的月壤发电技术研究

随着中国航天技术的进步及数据的积累,深空探测是未来中国航天事业发展的必然方向。月球探索必然成为深空探测的门槛及首要目标,建立月球科研站是解决未来月球科学问题的关键。月球作为卫星,拥有丰富原位资源,月壤热导率极低,同时月球环境月昼极高温、月夜极低温,结合温差发电技术,构建月壤温差发电系统,可对月球科研站电能源提供支持,特别是月夜期间,月壤温差发电系统仍能稳定持续提供电能。提供了月壤温差发电系统的设计思路,针对当前技术能力,提出月昼、月夜期间使用两套月壤温差发电模块,月昼期间月壤温差发电系统作为月球科研站电能源的补充,月夜期间作为主要电能源供应。同时分析了月壤温差发电系统未来研究方向,针对月壤温差发电系统常温、低温的工作温度,分析了当前主流常温、低温温差发电材料Bi2Te3、α-MgAgSb、Bi-Sb合金、CsBi4Te6的技术水平,并且提出将级联技术应用于月壤温差发电系统之中,可有效提高温差发电器件平均ZT值,提升发电效率。

Outage Performance of Cognitive DF Relaying Networks Employing SWIPT

In this paper, the outage perfor- mance of a cognitive relaying network over Nakagami-m fading channels, employing simultaneous wireless information and power transfer （SWIPT） technology is analyzed and evaluated. The operation of this network is considered in conjunction with the convention- al decode-and-forward （DF） and incremental DF （IDF） protocols. For the conventional DF protocol, it is assumed that there is no direct link between the secondary transmitter （S） and the secondary destination （D）, while （for both protocols） after harvesting energy, the relay node （R） always helps to forward the resulting signal to D. However, for the IDF protocol, R assists in relaying S＇s information to D only when the direct communication between S and D has failed. Furthermore, for both DF and IDF protocols, we assume there is no power supply for R, and R harvests energy from the transmitted signal of S. We derive exact ana- lytical expressions for the outage probability at D in DF and IDF protocols, respectively, in terms of the bivariate Meijer＇s G-function. Performance evaluation results obtained by means of Monte-Carlo simulations are also provided and have validated the correctness of the oroDosed analysis.

Energy Flexibility in the Power System： Challenges and Opportunites in Philippines

Energy flexibility can address the challenges of large scale integration of renewable energy resources and thereby increasing imbalance in the power system. Flexible power system can provide reliable supply, low electricity cost and sustainability. Various situations and factors influence the adoption of the flexibility solutions, such as flexible electricity generation, demand-response, and electricity storage. This paper tries to analyze the current energy flexibility solutions and the factors that can influence the energy flexibility adoption. This paper takes Philippines as case study to provide an overview of the current condition of the Philippines＇ power system and discuss the energy flexibility in the Philippines＇ power system. A further discussion and recommendation is conducted in the end of the paper.

On Issues of Large-Scale and Long-Distance Transmission of Wind Power

While having constantly developed for five years,China's wind power meets its bottleneck of further development in fast-growing areas due to the insufficient market accommodation.In contrast,the Central China and the East China have experienced the shortage of coal,oil and natural gas for power generation in recent winters.Hence,how to handle the discrepancy between insufficient accommodation and short energy supply has become the focus of attention both domestically and abroad.Taking Jiuquan Wind Power Base as an example,the reverse distribution between the energy resources and the consumer market,the wind power accommodation and the energy transmission are analyzed;the necessity and feasibility of long-distance power transmission are also discussed,which presents a technical roadmap for the long-distance transmission of thermal and wind power in combination.

Economic Impact of Renewable Generation on the Cost of Energy Supply

This article presents an analysis of the economic impact of non-dispatchable generation on the cost of the energy supply. It aims to analyze the economic impact of the renewable generation in Spanish production and thus to help prospective investors in renewable generation projects to analyze the situation of the Spanish electricity market. With that target, the current situation in Spain is shown and then using a MATLAB program, the economic impact of the renewable generation on the Spanish daily is analyzed.

Solar Radiation and Temperature Measurement of Solar Dish Concentrator System

Concentrating solar power （CSP） technologies could be one of the major contributor to worlds future energy needs and which would be cheap and clean sources of energy. This would improve energy utilization, higher conversion efficiency with reliable and affordable supply of electricity to the public. The proposed approach is using 18 inch diameter of solar dish concentrator to measure the solar radiation using the aluminium foil as a reflector. In this paper, solar radiation is collected to investigate the solar fraction on incoming solar energy in wet climate.

Development and Commercialization of New Autonomous Low Power Systems for Energy Harvesting

This paper evaluates new technologies for energy harvesting from the environment. We assess the reliability, accuracy, and autonomy of low power electronic devices, their market opportunities, and their ability to enhance sustainable development. For small, portable applications that need long lifetime energy supply systems, size, width, finite energy lifetime, and the need for replacement are important drawbacks. New supply alternatives should be explored that are able to make recharging easier or to remove battery dependence altogether. A new trend in the energy sources for low power applications has emerged in recent years, involving the harvesting of the energy available in the environment to supply power for electronic applications instead of using battery technologies that provide only short, finite amounts of energy. In this paper, we describe an all-purpose module of energy harvesting from mechanical, thermal, solar and RF energy sources developed at the University of Barcelona. We provide proof of concept in order to incorporate this novel energy technology in a wide range of applications and environments.

Considerations of Electricity Supply Quality in Spain

The quality of supply in Spain is regulated by Act 54/1997 as the basic standard and further developed by Royal Decree 1955/2000, among others. Also this law （1997） introduces the division between generators, distribution companies and retailers. The aim of this paper is to provide an overview of the fundamental parameters to be taken into account when examining the status of national regulations in Spain on the quality of electricity supply, in addition to describing the various agents intervening in these. There are two more aspects to consider： the guarantee of supply and energy is provided at the lowest cost to consumers. The authors propose to include phase-shifting transformers at specific strategic points, in accordance with power flow control principles in parallel circuits. Finally, it can be concluded that Royal Decree 222/2008 needs reviewing and applying effectively, as do modifications to Royal Decree 1995/2000 providing remuneration that effectively induces electricity companies to invest in their networks, and ends with ＂a well-paid electricity company is obliged to invest in network improvements＂.

Modeling Relative Humidity Effects on Power Electronic Performance

Variations in the behavior of power supplies caused electrical behavior dependence with environmental conditions. by environmental conditions require accurate characterization of the This paper introduces models to help predict relative humidity （Rtt） and other environmental factors influence on sensitive circuitry in power electronic systems. The resistivity and permittivity of an insulator have been modeled using different water contents i.e. RH, such model also included the mechanical properties of the design. An application example of a high power density, high voltage DC-DC converter is used to verify the results.

Design Methods for Improving the Performance and Thermal Stability of Radar

The radar power supplies exhibit a complex electronics. The development of more and more compact systems leads to master the interaction between different parts of the power supply while reducing electronic circuits, magnetic and thermal couplings from the constitutive circuitry. The consideration of these phenomena is very difficult at the design of the power supply. This paper presents two complementary methods based first on a circuitry model for the quantification of heat sources and secondly on finite element model for heat diffusion. This approach can help a designer in the goal of improving the performances and thermal stability of radar tied to the supply circuit subset.

Statistical Analysis and Energy Planning of Electric Power Supply Systems with Intelligent Control

The study presents possibilities for reconstruction of electric power supply systems in Bulgarian Black Sea resorts and possibilities to use statistical methods in energy planning. The paper shows the use of classic statistical methods in combination with advanced digital measurement systems in order to obtain the correlation dependencies, nature of energy consumption and opportunities for energy forecasting. The main purpose of the study is to obtain statistical dependencies of the nature of power consumption and correlations between electricity consumption and ambient temperature in order to improve the accuracy of energy planning. The analysis includes application of energy management systems for proper energy planning, improving economical efficiency and reducing power and energy losses.

Life Cycle Evaluation of Energy Supply Technologies in China by Energy Chain Multi Layered Model

China has a large potential to reduce CO2 emission in the Asian region. In this study, life cycle analyses of energy supply technologies in China were evaluated for enforcing the clean development mechanism （CDM）. Wind power, integrated coal gasification combined cycle （IGCC）, natural gas combined cycle （NGCC）, and ultra super critical power plant （USC） were chosen as new power generation technologies. The system function of the developed model was enhanced to extend coverage to new technologies for power generation systems in China. CO2 intensities, energy profit ratios, and CO2 emission reductions are estimated based on the assumption that these power plants were constructed at Shanxi, Xinjiang, and Shanghai. Wind power showed the best results with regard to CO2 intensity and energy profit ratio. However, it also has some disadvantages with regard to the utilization factor and the lifetime. It is considered that wind power will become an important part of CDM activities as the utilization factor and the lifetime improve. An NGCC using a natural gas pipeline was found to be most advantageous in reducing CO2 emission. IGCC and USC were inferior to NGCC with regard to energy profit ratios and CO2 emission reductions.

Research and development of micro electret power generators

As the size of the electronic system continuously reduces, characteristics of small volume, light weight, high energy it is very important to develop micro power generator, which has density and continuous energy supplying. Vibration energy exists widely in daily environment. Micro vibration power generator can harvest and exchange the vibration energy to the electrical energy. Micro electret power generator is one kind of the power generators for harvesting vibration energy and has been paid much attention by researchers. This paper describes the development and status of micro electret power generators, including electret materials and charging methods, vibration energy harvesting structures and conversion efficiency improvement.