多层压电电源储能特性试验研究

通过试验对多层压电电源的储能特性进行了研究 .试验结果表明 ,储能电容C上的充电电压与多层压电电源的层数成正比 ,与C的电容值成反比 ,为该电源的设计提供了设计依据 .该文还对该电源在小口径高炮引信中的应用进行了可行性分析 .多层压电电源的激活时间短 ,能量小 ,可对短时工作的低功耗电路提供电能 ,适用于高炮实时装定的精确计时。

基于光储一体逆变器的10kW储能系统试验研究

针对传统逆变器供电方式单一不环保、工作模式不灵活的问题,文章研究了光伏和锂电池双供电模式的逆变器,并基于该逆变器搭建了10 kW储能系统试验平台。在并网运行状态下,设计了稳态试验和动态试验。试验结果表明:稳态运行时,该逆变器能平稳输出与电网同频同相的电压电流,且电流谐波畸变率小,直流电压波动在允许范围内;动态运行时,该逆变器在负载切换瞬间直流电压波动小,恢复时间短。因此,光储一体逆变器能够很好地满足10 kW储能系统的技术要求。

配电变压器储能式短路冲击试验方法研究及应用

配电变压器进行短路冲击试验过程中需要较大的瞬时能量,若采用专用线路以及发电机组的冲击方式需要同步开关、调节阻抗、发电机以及专用线路等,不仅现场可操作性低,同时存在影响系统稳定性的风险。为解决上述配电变压器短路冲击中存在的问题,文中基于变压器、储能电容器与电力电子变换装置,提出了配电变压器储能式短路冲击试验方法,并在此基础上设计了一套配电变压器储能式短路冲击试验系统,实现了短路冲击试验状态量的快速调节,并通过同类型储能冲击装置的串并联完成冲击容量的提升。通过仿真以及现场试验,文中所提设计配电变压器短路冲击试验系统大幅度降低了配电变压器短路冲击对电源侧容量的要求,现场试验中具有较好的可操作性。

Design and development of real-time query platform for big data based on hadoop

This paper designs and develops a framework on a distributed computing platform for massive multi-source spatial data using a column-oriented database(HBase).This platform consists of four layers including ETL(extraction transformation loading) tier,data processing tier,data storage tier and data display tier,achieving long-term store,real-time analysis and inquiry for massive data.Finally,a real dataset cluster is simulated,which are made up of 39 nodes including 2 master nodes and 37 data nodes,and performing function tests of data importing module and real-time query module,and performance tests of HDFS's I/O,the MapReduce cluster,batch-loading and real-time query of massive data.The test results indicate that this platform achieves high performance in terms of response time and linear scalability.

Laboratory Test Rig of a LHTES （Latent Heat Thermal Energy Storage）： Construction and First Experimental Results

The present experimental investigation covers the construction of a LHTES （latent heat thermal energy storage system）, which uses NaNO_3 （sodium nitrate） as PCM （phase change material）. The storage unit is filled with 300 kg of the PCM. For the heat transfer, a vertically arranged bimetallic mono tube with longitudinal fins is used. The fins increase the heat flux into/from the PCM. Thermal oil is used as a heat transfer medium, as it allows working temperature up to 400 ℃. This thermal energy storage is able to store 60 kWh of thermal energy and can be loaded with a power up to 200 kW. One part of the investigation results presented in this paper was the determination of the storable energy and the comparison with data from literature and calculations. Additionally, the melting behavior of the PCM was measured with temperature sensors located at different positions over the height of the storage unit. Finally, the entrance of the heat transfer medium was changed from the top to the bottom of the thermal energy storage unit and a different melting behavior could be detected.

The Efficiency Improving of Traction Drive Test Bench with Supercapacitor Energy Storage System

For development of passenger electrical transport, it is necessary to use energy more rationally. One of methods of vehicle power efficiency increase is installation of on-board energy storage systems. For studying of system operation, it is necessary to carry out a lot of experiments, therefore it is favorable to use the test bench and its computer model for reduction of the number of physical experiments. In this article, the results of computer modeling for the optimization of traction drive test bench by adjusting of the operation parameters of supercapacitor energy storage are described. Test bench operation is considered in cases of the energy storage system working at various selected supercapacitor initial voltages. Maximal increase of possibility of vehicle test bench regenerative braking with minimal decrease of autonomous power supply mode possibility is investigated. There is estimated the energy storage system efficiency improving measures dependence from supercapacitor operational voltage ranges. Parameters at which the minimum losses of energy are observed are revealed. Dependence of energy storage system discharge power on the most admissible supercapacitor current is established.

Carbon dioxide reforming of methane over bimetallic catalysts of Pt-Ru/γ-Al_2O_3 for thermochemical energy storage

The reaction of CO2 reforming of CH4 has been investigated with y-A1203-supported platinum and ruthenium bimetallic catalysts, with the specific purpose of thermochemical energy storage. The catalysts were prepared by using the wetness impregnation method. The prepared catalysts were characterized by a series of physico-chemical characterization techniques such as BET surface area, thermo-gravimetric （TG）, transmission electron microscope （TEM） and X-ray photoelectron spectroscopy （XPS）. In addition, the amount of carbon deposits on the surface of the catalysts and the type of the carbonaceous species were discussed by TG. It was found that the bimetallic Pt-Ru/7-A1203 catalysts exhibit both superior catalytic activity and remarkable stability by comparison of monometallic catalysts. During the 500 h stability test, the bimetallic catalyst showed a good performance at 800 ~C in CO2 reforming of CH4, exhibiting an excellent anti-carbon performance with the mass loss of less than 8.5%. The results also indicate that CO2 and CH4 have quite stable conversions of 96.0 % and 94.0 %, respectively. Also, the selectivity of the catalysts is excellent with the products ratio of CO/H2 maintaining at 1.02. Furthermore, it was found in TEM images that the active carbonaceous species were formed during the catalytic reaction, and well-distributed dot-shaped metallic particles with a relatively uniform size of about 3 nm as well as amorphous carbon structures were observed. Combined with BET, TG, TEM tests, it is concluded that the selected bimetallic catalysts can work continuously in a stable state at the high temperature, which has a potential to be utilized for the closed-loop cycle of the solar thermochemical energy storage in future industry applications.

Field Test of Energy Storage System on Urban Transit System

The energy storage system charges the energy generated during braking and discharges it again when a vehicle accelerates on urban transit system. The energy storage system is considered to be one of the useful devices for energy storing and recycling. The energy storage system was developed and installed on the test track of Gyeongsan LRT in Korea. This paper presents the test plan and how much energy is saved by the energy storage system through the field test. When the energy storage system is on/off, the energy saving rate is obtained.

Investigation of Excessive Material on Insulating Properties Using Different Heat Transfer Fluid for Thermal Energy Storage Development

Though TES （thermal energy storage） is developed hugely in most of the solar power generation plants, it is less growth in implementing a modular type of TES in a solar plant, e.g., solar dish/stifling engine application. The main issue in designing the TES system is its thermal capacity of storage materials, e.g., insulator. This study is focusing on the potential waste material as an insulator for thermal energy storage applications. The insulator usage is to reduce the heat transfer between two mediums and the capability is measured by its resistance to heat flow. It is needed to obtain optimal materials to energy conversion at the same time reduce the waste generation. Therefore, a small-scale experimental testing of natural cooling process of an insulated tank within a confined room without any forced cooling system, e.g., fan. The testing is repeated by changing the insulator using the potential waste material from natural and industrial waste and also by changing the HTF （heat transfer fluid）. The analysis is performed on the relationship between heat loss and the reserved period by the insulator. The results indicate the percentage of period of the insulated tank withstands the heat compared to non-insulated tank, e.g., cotton reserved the period of 14% more than non-insulated tank to withstand the heat transfer of cooking oil to the surrounding. The paper finally justifies the most potential waste material as an insulator in different heat transfer fluids.