bluuebunny/crossref_metadata_2025 huggingface dataset:
Determination on Acidification Point during Anaerobic Digestion of Biodegradable Municipal Solid Waste
Authors: Dai Ben Lin , Zhu An Feng , Mu Fei Hu , Xu Ning , Wu Zhen
Published: June 2014

The aim of this work was to investigate the acid inhibition during the anaerobic digestion of municipal solid waste. Four biodegradable substrates of soybean, fat meat, rice and celery cane were considered in this paper. A series of anaerobic co-digestion tests were performed on the four substrates at the load of 1.0gVS/(L•d) and anaerobic granular sludge. The method to calculate the lowest acidification points of the four substrates was provided by the least squares method, and it is verified by the measured data, and good agreements are achieved.
Crystallization and Mechanical Properties of Glass-Ceramic from Silicon Slag
Authors: Li Hang , Liu Li Qiang , Jing Min , Wang Zhi Gang , Wang Zheng , Xing Rui Ping
Published: June 2014

The glass-ceramic materials were produced from silicon slag with the addition of talcum powder and TiO2 by melting them in an electrically heated furnace and subsequent heat treatment at various temperatures and time. The microstructure and crystallization behaviors of glass–ceramics have been investigated by differential thermal analysis (DTA), X-ray diffraction (XRD) and scanning electron microscopy (SEM). With the increase of silicon slag content, the sequent precipitate phase is: krinovite Na (Mg1.9Fe0.1)Cr (SiO)3O, pseudobrookite Fe2TiO5 and anorthite Ca (Al2Si2O8), enstatite ferroan MgFeSi2O6, and albite Na (AlSi3O8). The shape of crystals was spherical grains. The glass–ceramic sample obtained from 70% silicon slag had the excellent mechanical performance including flexural strength of 200.45 MPa and Vickers micro hardness of 909.72 MPa.
Study on Gasification Characteristics of Petroleum Asphalt in a Two-Stage Gasifier
Authors: Li Guang Yu , Xu Shi Sen , Xia Jun Cang , Ren Yong Qiang
Published: June 2014

The gasification performance of petroleum asphalt in a two-stage gasifier was investigated through experiments and simulations. The analysis results of asphalt samples show that the asphalt has characteristics of high volatile content, high calorific value, and low ash content. Coal pyrolysis model, gas-solid heterogeneous reaction model, gas homogeneous reaction model and Gibbs free energy minimization method were employed to build the two-stage entrained flow gasification model and simulate the asphalt gasification process using Aspen Plus software. The results indicate that the cold gas efficiency of asphalt is 3% higher than that of bituminous coal, while the consumption of coal and oxygen is 40% lower than that of bituminous coal. The gasification performance of asphalt is superior to that of coal. In addition, the cold gas efficiency of asphalt can be increased by about 3% when the two-stage gasification process is employed. The utilization rate of coal in the two-stage gasifier is much higher than that in traditional one-stage gasifier.
Nucleation Mechanism of Biodiesel Derived from Palm Oil at Low Temperatures
Authors: Chen Xiu , Jin Xin , Lai Yong Bin , Hu Jia Min , Shu Jun Feng , Zhang Yu Qi , Wang Bo , Yuan Meng Hong
Published: June 2014

The compositions and crystallization process at low temperature of palm-based biodiesel (PME) are investigated. In this work, we show that PME is mainly composed of fatty acid methyl esters of 14-24 even-numbered C atoms: C14:0-C24:0, C16:1-C22:1, C18:2, and C18:3. Palm-based biodiesel crystallization comprises three steps, viz., forming supersaturated solution, nucleation and ester crystal growth; the driving force for saturated fatty acid methyl esters nucleation is the degree of supersaturation. The rate equation of nucleation is put forward. The objective of this research is to provide theoretical support for hindering the ester crystal nucleation and growth, and improving the cold flow properties of PME.
Research on the Compression Mechanism of Densified Biomass Fuel
Authors: Zhang Xia , Cai Zong Shou , Chen Li Hong , Chen Ying
Published: June 2014

By using mechanical force, biomass can be compressed or extruded into densified solid fuel with higher bulk density and higher calorific value, which makes it convenient in transportation and storage. The compressing technology of biomass is considered as one of the simplest and the most direct way to utilize biomass as a fuel in the world. However, due to the different chemical composition of biomass, the compression mechanism of biomass particles is different from other particles of coal, ceramics, metals and other materials. A comprehensive study on the compression mechanism of densified biomass fuel was carried out in this paper. The effects of the common chemical components of biomass on the quality of the densified fuel were further explored. The purpose of this paper is to provide a theoretical basis and a technical reference to understand the compression mechanism of biomass.
Experimental Studies on a Solar Low Temperature Multi-Effect Distillation Desalination System
Authors: Feng Dong Dong , Pei Xiao Bin , Zhang Feng Ming , Zhao Yun Mo , Yang Wei , Chen Shun Quan , Xu Shi Ming
Published: June 2014

Solar energy has been widely used in desalination systems. A low-temperature multi-effect desalination system driven by solar is constructed for a series of experimental studies. The results show that water production rate grows with solar radiation, and maintains at a high level between 12am to 4pm. The optimized heat water flow is 1400 kg/h and appropriate cooling water temperature is 24 °C, respectively.
Study on the Pyrolysis Characteristics of Microalgae by Microwave Oven
Authors: Chen Chun Xiang , Wei Hong Bo , Lu Zi Guang , Qin Wei Ping
Published: June 2014

In this paper, the pyrolysis characteristics of Chlorella vulgaris (C. vulgaris) (a kind of microalgae) under different microwave power and pyrolysis atmosphere are studied by microwave oven. The results show that under N2 atmosphere, a power of 1500W is required for optimal oil production, 2250W for optimal gas production and 750W for optimal residue. Under CO2 atmosphere, a power of 2250W is required for maximum oil production, 1500W for maximum gas production and 750W for maximum residue.
Analysis on Biomass Co-Fired Heating Technology in Northeast China
Authors: Guo Li Hua , Chen Li Ming
Published: June 2014

In order to reduce the environmental pollution of coal-fired heating, coal plus biomass co-firing has been put into test. In this experiment, based on the a 20t coal-fired steam boiler of heating company in northeastern region, through observing the data that generated by different fuels ratio, it did the economic and social analysis by using contrast method and computer technology. The results showed: when the ratio of straw and coal is 1:11, it gains optimal benefit.
Kinetics Model Comparison of Different Pre-Treated Sweet Sorghum Bagasse Pyrolysis
Authors: Chen Dong Yu , Hu Yan Qing
Published: June 2014

In order to find out the appropriate kinetic model for biomass pyrolysis, pyrolysis experiments of four samples (untreated biomass, HCl-washed, 3%KCl-treated and 10% KCl-treated) of sweet sorghum bagasse were performed by Thermogravimetry (TG) separately at different heating rates. The pyrolysis data was processed by the methods of Ozawa、Coats-Redfern integration and Achar-Brindley-Sharp differential, and the kinetic parameters were calculated. The results showed that the activation energy from deduced mechanism functions is more approach to the Ozawa’s than that from tentative mechanism functions, and the deduced mechanism functions can more realistically reflect the dynamic process four samples of sweet sorghum bagasse pyrolysis.
Study of Biogas Production from Wastes in Military Areas
Authors: Chanthakett Apina , Vivanpatarakij Supawat
Published: June 2014

The study of biogas production was conducted to find effective fermentation which will enhance digester gas manufacturing system and reduce waste in military areas. Co-digester between food wastes with pig manure was studied. The experiment was divided into three proportions of food waste and manure based on dry matter mass. The first is 100:0 which contains 26 kg. of food waste. The second is 85:15 which was composed of 22 kg. of food per 4 kg. of pig manure. And the third is 70:30 which contains 18 kg. of food per 8 kg. of pig manure. Leavening agent for digester came from pig manure. The 21 day experiment was carried out to collect and analyze biogas samples. According to these results, the proportion 85:15 produced a large quantity of biogas which was 1,134 liters. Methane generation rate is increasing and hydrogen is also high as 32.26%. The heating reached the highest value at 1.491 MJ. or 3.189 times compared to the proportion 100:0 in the experimental temperature of 31-33 °C
Study of Co-Pyrolysis of Huai Nan Coal with Cotton Stalk
Authors: Chang Teng Fei , Tang Chu Yang , Wang Ge , Gu Mei Yu , Jia Ying Dong
Published: June 2014

An experimental study on co-pyrolysis of biomass and coal was performed in a tubular furnace for comparison of product (tar, water, gas and char) yields and composition. The coal sample selected was Huai Nan bituminous coal (HN), while the biomass used was cotton stalk (CS), and the blending ratio of biomass in mixtures was 0/100, 5/100, 10/100, 20/100, 30/100, and 50/100. The blends of coal and biomass were heated 600°C at 5°C/min, and then kept for 15 min during the pyrolysis. The results indicated that there exist synergetic effects in the co-pyrolysis of biomass and coal. The tar yield was 9.33% higher than the theoretical value at the CS blending ratio of 5/100. The maximum light oil content in tar was 9.67% higher than the theoretical value at the CS blending ratio of 10/100.
Technical and Economic Evaluation of Hydrogen Production by Biomass Gasification in Supercritical Water and in Air-Steam Media
Authors: Wen Sheng , Wang Shu Zhong , Li Yan Hui , Wang Yu Zhen
Published: June 2014

Technical and economic conditions of hydrogen production by biomass gasification in supercritical water and in air-steam media have been evaluated. Reaction mechanism, technological process, product gas composition and operation costs of two processes were compared. Results indicate that biomass gasification in supercritical water has much more advantages than in air-steam medium, such as easier operation process, smaller machine area, high gasification efficiency, and less pollution, etc. There are no needs of biomass pretreatment and post-processing for product gas in supercritical water. Moreover, the proportions of hydrogen, carbon dioxide, methane are high, so these kinds of product gas all can be utilized. However, the cost of producing 1Nm3hydrogen in supercritical water is $0.6537, which is a little higher than $0.4228 in air-steam media. With the construction of more supercritical water unit and accumulation of more experience, hydrogen production by biomass gasification in supercritical water will have a more bright future.
The Small Town of Biomass Heating Evaluation Based on the Multi-Level Fuzzy Analysis Method
Authors: Mao Hu Jun , Lv Zi Qiang , Wang Chun Hui , Wang Li Hong , Zhao Di
Published: June 2014

China has abundant biomass resources and biomass heating is now at the stage of development in China. In view of the influence factors in the process of biomass heating this article use the Multi-level fuzzy analysis method to establish the Biomass heating evaluation model of small towns. Provides the reference for the promotion of living material heating way in small towns Based on economic factors, environmental factors affecting biomass heating of small towns, energy guide factors and technical factors were analyzed, and the factors affecting the biomass heating of small towns are comprehensive evaluation, It provides the reference for the promotion of living material heating way in small towns according to analyze the influence the economic factors, environmental factors, energy guide factors and technical factors and comprehensive evaluate the influence factors of biomass heating of small towns the Factors affecting the biomass heating of small towns.
Effects of Different Treatments on Properties of Biogas Fermentation with Ginger Skin
Authors: Liu Jing Hui , Zhang Wi Di , Yin Fang , Liu Jing , Zhao Xing Ling , Liu Shi Qing , Xu Ling , Chen Yu Bao , Yang Hong
Published: June 2014

In order to obtain gas potential and characteristics of ginger skin in biogas fermentation as raw material, and explore effect of different treatments on properties of biogas fermentation with ginger skin. At the temperature of 30°C, biogas fermentations with ginger skin were treated in two ways (natural decay and mixed with pig manure). Experiments were respectively set five different treatments (direct fermentation, natural decay, adding pig manure after natural decay (TS content of pig manure / TS content of ginger skin were respectively 1:1, 2:1 and 3:1)). The results showed gas potential of ginger skin and total gas production were respectively 118.08ml/gTS and 320ml, after the 11th day, the fermentation was in a serious acidification, as a result of stopping gas production. The fermentations with ginger skin which went through natural decay and adding pig manure after natural decay can both eliminate acidification which caused by use of ginger skin directly, and conduce to the fermentation with ginger skin. The fermentation with ginger skin which went through natural decay had higher degradation rate of TS, total gas production, TS gas potential and methane content than fermentation with ginger skin directly.
Research on the Maximum Power Point Tracking Technology of the Solar Power Supply System on Air Vehicle
Authors: Liu Zhong Tao , Jiang Kun Song
Published: June 2014

What are the photovoltaic properties of solar cell, the operating principle of DC/DC conversion, the overall scheme of MPPT as well as the algorithm of maximum tracking power point combine the actual situation of space power system, with the introduction of the modular MPPT algorithm. These aim to study how to improve the utilization efficiency of the field monitoring equipment about the solar-powered accumulator energy-saving control system for solar energy. Using solar power meter can detect changes curve of light intensity so as to obtain parameters for the simulation, and then we can establish the photovoltaic array simulation model to gain the three actual tracking power curves of the combined algorithm, the perturbation method and the incremental conductance method and stabilize the best output voltage of solar cells while using Buck Circuit to reduce voltage to charge for nickel-cadmium accumulator pack. As a result, the system can achieve the uttermost steady operation with the reliability improved. The design adopts the DC/DC boost circuit to providing charging system for battery and utilizes the DSP program to generate the PWM to track the maximum power output (MPPT). This system has the advantages of the simple circuit structure, the good waveforms and the accurate measurement result, which conforms to the design requirements.
Experiment Study on the Biogas Fermentation of the Cynodon dactlon (L.) Pers.
Authors: Li Ying Juan , Yang Bin , Liu Jing , Yang Hong , Yin Fang , Zhang Wu Di
Published: June 2014

In order to get the biogas fermentation potential of the Cynodon dactylon (L.)Pers, this experiment was conducted the CSRT anaerobic batch fermentation with the Cynodon dacytlon (L.)Pers. as the raw material and the mixed cultivate as inoculum, on the condition of feed concentration of 6.20%, temperature of 30°C and pH of 7.5. The fermentation period lasted 42 days. The results showed it produced total 4400mL biogas while went over the 80% of the biogas production in the early 25 days. The TS biogas production rate was 311mL/g, the VS biogas production rate was 372mL/g, and the raw material biogas production rate was 288mL/g, which implicated that Cynodon dactylon (L.)Pers. is a potential biogas fermentation raw material.
Experimental Study on Potential of Biogas Fermentation with Oxalis corymbosa
Authors: Zhang Li Juan , Zhang Wu Di , Yin Fang , Zhao Xing Ling , Liu Jing , Liu Shi Qing , Chen Yu Bao , Yang Hong
Published: June 2014

In order to gain the biogas production potential from Oxalis corymbosa, the anaerobic batch fermentation which were divided into the control group (120ml inoculum), the experimental group (120ml inoculum and 125g Oxalis corymbosa) were performed at 30°C. The results indicated that the net biogas production of the experimental group during total fermentation time of 50 days was 3220 ml. Further, it was calculated that the biogas yield of Oxalis corymbosa was 338ml/g TS or 388ml/g VS. The result indicated that Oxalis corymbosa can be used for biogas fermentation and the fermentation production potential was good.
The Application of Biogas Power Generation Technology - in Dafeng City Haifeng Dairy Farm Biogas Power Generation Projects, for Example
Authors: Yu Guo Li , Yang Dong , Zhang Meng , Wang Shao Lin
Published: June 2014

With the renewable energy more and more get people's attention, biogas power generation system will have a good hair development prospect. Dafeng city haifeng dairy farm biogas power generation project success running showed that biogas power generation has a certain application prospect, and the use of marsh fertilizer is an important approach to improve the running efficiency of biogas engineering.
Planting Decision of Bio-Energy Feedstock under the Threat of Regulatory Taking
Authors: Xue Ming Gao , Xue Ming Gao
Published: June 2014

The world is facing energy crisis and the search for renewable bio-energy is currently one of the most important issues. Energy plant as a kind of bio-energy feedstock has attracted more and more attention, especially its planting issue. Short rotation coppice (SRC) is used as a proxy for other energy plants. This paper investigates farmers’ planting decisions of SRC under the threat of regulatory taking which is rarely mentioned in the previous relevant literatures. We use real options approach and especially take the risk of regulatory taking into account to analyze whether or not to grow SRC instead of traditional crops on farmland. It turned out that the threat of regulatory taking reduces the investment threshold and stimulates farmers to grow SRC. In other words, the threat has potential to improve the development of bio-energy.
Comparative Analysis of HVAC, HVDC and Hybrid HVAC-HVDC Transmission System Based Offshore Wind Farm
Authors: Wu Yuan Kang , Lee Ching Yin , Lee Dong Jing , Huang Yung Ching
Published: June 2014

Taiwan is developing the renewable energy actively, in which the wind energy is seen as one of important resources. However, the suitable locations for wind farm constructions are less and less on the shore, and the trend of wind farm development in the future will toward to offshore where the installation capacity of the wind farm could reach hundreds of megawatts. As the installation capacity of the wind farm increases, the effects on the interconnected AC grid are also more notable. In this paper, the off-peak system in Taiwan is used as a studied system in which the Penghu area and Taiwan grid is connected by submarine cables. This study explores the wind farm transmission system including HVAC, HVDC, and hybrid HVAC-HVDC systems and compares the differences of their impact on the system.
Development Status, Restricting Factors and Strategies for China's Wind Power Industry
Authors: Sun Li , Hao Sheng Yue , Li Jian Ge , Wu Zeng Hong
Published: June 2014

The development of new and renewable energy is the key to Chinas future energy strategy. The development of wind energy resources has been drawing our attention because of its unique advantages and it grew rapidly recently. At present, Chinas wind energy industry has come into large-scale stage of rapid development and has made remarkable achievements while it also faces great challenges. Based on the overview of wind energy resources and its development status in China, the problems and restrictive factors of Chinas wind energy industry were analyzed in this paper, and its proper strategies for further wind energy development were discussed also.
Research on Impact and Solutions of Voltage Stability of Distributed Wind Power Integration
Authors: Li Guang Lei , Wang Zhao Xin , Deng Hua , Wang Yu Jia , Chen Tao
Published: June 2014

Aiming at the problem of lack of engineering practice experience and corresponding technology research, this paper reveal the interactive mechanism of distributed wind power and power grid. Based on the actual network frame and planning network frame, this paper establish analysis database, analyze problem of voltage stability by large amount of wind power integration into power system, propose the adjustment measures of voltage, put forward operation control mode of distributed wind. These can be used to guide the large-scale development of distributed wind power, which makes the development of distributed wind power guided by resource type of guiding transition to grid type.
Research on Wind Energy Integration in Matsu Islands
Authors: Wu Yuan Kang , Tseng Ying Chuan , Chen Bin Kwie , Lee Dong Jing , Huang Yung Ching
Published: June 2014

The energy costs of island systems are usually higher than those of large grid systems. Therefore, majority of the countries worldwide usually initiate their plans for developing renewable energy on remote islands. The electricity cost of Matsu Islands accounted for roughly 5% of total annual deficit of Taiwan Power Company. Hence, power generation is a critical energy economics issue for the Matsu Islands. This study will examine the possibility of wind power integration into Matsu Islands and investigate the transient frequency response in this system when a fault or disturbance occurs. According to the simulation results, the main target of this study is to improve the system stability on the remote island systems, and achieve the maximum renewable energy penetration.
Simulation of the Affected Wind Power Transient Stability by Means of SVC and STATCOM
Authors: Wang Zhi Jie , Liu San Ming , Sun Xia , Su Xin Xia , Chen Li Juan , Pei Ze Yang
Published: June 2014

In the paper the models of IG and DFIG have been analyzed, and then the two reactive power compensations SVC and STATCOM have been introduced. Finally, use the simulation software of power system PSCAD to simulate the process of wind power integrating into grid. In the simulation results, it’s obvious that the DFIG has better transient stability than IG; install SVC or STATCOM can improve transient stability of wind farm, but SVC is apt to cause harmonic pollution, and STATCOM can improve transient stability to both kinds of generators.
Study on Coordinated Development between Wind Power and Grid
Authors: Shi Kun Peng , Zhao Wei , Fu Ji Yue , Fan Guo Ying , Li Ting
Published: June 2014

In this paper, the security and consumption problems of large-scale wind power integration to electric grid are briefly introduced, focusing on serious events that many installations went off the grid, failing to “ride through fault” (RTF), which happened successively since 2011. Then the mechanisms of coordinated development between wind power and electric grid are discussed, and suggestions on management & technical measures are proposed to realize a great friendly wind farm which can be developed in a scientific, healthy and sustainable manner.
A Model of Wind Turbine’s Flexibility Shaft
Authors: Ding Guo Dong , Liu San Ming , Chen Qin Qin , Liu Jian Peng , Yang Ming Li
Published: June 2014

Wind power is a new technology compared with thermo power, the damage of sub-synchronous oscillations cloud bring to the shaft of wind turbine do not get enough notices. There are few studies on wind turbines sub-synchronous oscillation now, which are built on the model of rigid shaft. As we all know wind turbine shaft is unlike the shaft of stream turbine, there are couplings and gearbox in wind turbine which make the shaft flexible, so the studies of wind turbine sub-synchronous oscillations based on rigid shaft model are not reasonable, this paper introduces a new flexible shaft model for studying of wind turbine sub-synchronous oscillations. Flexible equipments, such as joints and gearbox are taken into consideration when the model are set up, so this model is far more scientific.
A Study of Wind Power Inverter Operating in Grid-Connected and Stand-Alone Mode
Authors: Zhang Ying Li , Chen Yi , Chen Wei Hua
Published: June 2014

Wind turbine system (WTS) is a representative distributed power generation (DG). Establishment of WTS model and control strategies is of important practical significance. One critical field is the research of inverter system. It should be operated in stand-alone (SA) or grid-connected (GC) mode. The purpose of this thesis is to establish simulation platform of WTS inverter control model in Matlab/Simulink environment, which includes two typical DG control strategies, PQ and V/f. The wind fluctuation makes inverter output power harder to follow wind turbine (WT) power. In GC mode, PQ strategy was adopted to balance inverter output power and WT generated power. In SA mode, V/f strategy was applied to keep emergency load voltage stable. The bidirectional smooth transitions between SA and GC mode were well accomplished. Simulation proves the model can survive grid failures or load shedding. The study can be used in research of DG operation control.
Experimental Study on Stirring Wind-Heating Devices
Authors: Zhao Jian Zhu , Liu Qing Miao , Wang Feng Chen , Yuan Mei , Huang Shao Jiong
Published: June 2014

To improve the using efficiency of clean energy, in this investigation, three wind-heating devices, nonlayered-stirring heating device, layered-stirring heating device and layered extruded stirring heating device, were designed, fabricated and tested. The performance of these three devices was investigated experimentally. Results show that, under the experimental conditions, the layered extruded stirring heating device is the most efficient, and its heating efficiency reaches 46.4%. Then, the computational fluid dynamics (CFD) models were established base on these three devices. The comparative analysis of the simulation and experimental results, both obtained consistent heating law. This suggests that the use of the software CFD simulating the stirring heating device is feasible.
Numerical Simulation on 2D Savonius Rotor in Ground Effect
Authors: Zhu Jian Yong , Wang Kai , Ruan Hai Bin
Published: June 2014

The Aerodynamic Performance of 2D Savonius Rotor in Ground Effect is Numerically Simulated through Solving Unsteady Compressible RANS Equations and the Standard k-ε Turbulence Model. the Calculation Results Indicate that the Ground Effect Influences the Starting Performance and the Power Output. the Optimal Height between the Ground to the Lowest Part of the Rotor is 0.4 Times Rotation Diameter, at which the Starting Performance is Optimal. the Ground Effect also Increases the Power Coefficient and the Tip Speed Ratio Corresponding to the Maximum Power Coefficient. when Determining the Rated Tip Speed Ratio, the Fluctuation of the Torque Values and the Power Coefficient with Different Tip Speed Ratio should be Synthesized.
Design and Investigation of Dual Grating Periodic Structure Thin-Film Solar Cell
Authors: Yu Li Li , Yang Li Xia
Published: June 2014

The studied results found it can not only reduce the thickness of the solar cell but also improve the light absorbed efficiency by using grating as light trapping structure. In this paper, a dual grating periodic structure is designed to improve light absorption efficiency over the spectrum range 330-1400 nm. Then the relationship between groove-depth of dual grating and absorption efficiency is investigated by using finite difference time domain method (FDTD) combining with periodic boundary conditions (PBC).
Research on the Met Mast Siting Used in Post Assessment of Mountain Wind Farm
Authors: Yang Jia Yuan , Woo Yu Mo , Sheng Ke , Tang Yu Hui
Published: June 2014

Abstract. For a mountain wind farm in southern China, the paper used CFD software, METEODYN WT, to simulate the wind in all directions to assess their speed-up factor, turbulence intensity, inflow angle and horizontal deviation caused by the terrain. The turbulence intensity, the horizontal deviation and the inflow angle in the met-mast position should be low or small, and the speed-up factor should be able to represent the average level of all the wind turbine sites. The positional relationship of the wind turbine and met-mast is reference to IEC61400-12-1. The paper provided two optional areas.
The Real-Time Wind Turbine Fault Diagnosis Method Based on Safety Evaluation Model
Authors: Yang Ming Li , Liu San Ming , Lv Yong Hai , Zou Yang , Ding Guo Dong
Published: June 2014

In order to determine the best maintenance time of wind turbines and identify the fault type when it is the best time to do the diagnosis work immediately. The establishment of 4-level safety status model for critical parts of wind turbines, based on wind turbine parts’ significance level, was proposed. According to the corresponding safety level of the wind turbines in real-time working status, you can decide whether the wind turbine needs diagnosis at the time or not. Therefore, we should take measures to monitor the real-time working conditions of the wind turbine’s critical parts, confirming whether the critical part need the fault diagnosis analysis or not according to its real-time working safety status. If it is the right time, then the corresponding fault diagnosis process will be initiated, through which the real online fault diagnosis can be achieved. The multi-scale wavelet decomposition and Hilbert transformation was employed to get the useful parameters such as amplitude, effective value, mean value, kurtosis value and so on of the corresponding waveform to confirm the concrete diagnosis type.
The Research of Wind Power Fluctuation in Different Time Intervals
Authors: Zhang Yi Hui
Published: June 2014

Power from wind turbines is mainly related to the wind speed. Due to the influence of the uncertainty of the wind, intermittent and wind farm in units of the wake, wind power has fluctuations. Based on the field measurement, it is found that t location-scale distribution is suitable to identify the probability distribution of wind power variations. By analyzing the fluctuation of a single in different time intervals, we find that the distribution of wind power fluctuation possesses a certain trend pattern. With the length of the time window increasing, the fluctuations increase and some information has been missed. We define an index to calculate the quantity of missing information and can use that to evaluate whether a certain length of interval is acceptable.
Design of a Continuous Solar Desalination System with Humidification-Dehumidification Cycle
Authors: Chen Yang , Ma Qing Fen , Xie Li Xin , He Wen Jin
Published: June 2014

A continuous solar desalination system with humidification-dehumidification cycle was devised. Solar energy was chosen as the main heat source, the electric heater the auxiliary heat source, and the hot water reservoir the energy storage unit. To ensure the 24-hour continuous production of fresh water, four specific operation modes were designed and analyzed for the conditions of average, excess, insufficient and no illumination intensity respectively, based on which the methods for the judgment and calculation of process parameters were derived.
Research on Peak Load Regulation Demand of Power System with Large-Scale Wind Power Integration
Authors: Xu Jian Fei , Shao Jian , Zhang Bu Han , Yu Peng , Zhang Kai Min , Jin Bing Jie , Ge Teng Yu , Dai Xiao Kang , Deng Wei Si
Published: June 2014

In china, increasing large-scale wind power integration has brought much more peak load regulation demand, which is the bottleneck of the integration of wind power to systems. This paper analyzed the influence mechanism of large-scale wind power on peak load regulation demand. And critical indicators are constructed based on the daily peak-valley difference to evaluate peak load regulation demand caused by wind power integration. Statistical analyses based on large number of actual dates reflect the influence of large-scale wind power integration on peak load regulation demand, which can help provide more decision-making information for planning and operation.
Study on Sub-Synchronous Control Interaction (SSCI) of Wind-Power Generator
Authors: Liu Jin , Zhao Shu Qiang
Published: June 2014

Large-scale wind turbine generators with power electronic converters that operate near series compensated transmission lines are susceptible to un-damped sub-synchronous oscillations. This sub-synchronous oscillation is called Sub-synchronous Control Interaction (SSCI). With the rapid development of wind power technology, SSCI emerges as a new sub-synchronous oscillation phenomenon. The first SSCI event occurred for a wind farm in America in2009, which resulted in damage to the wind turbines. The origin of SSCI is presented and its characteristics of different types of wind turbines are summarized. Then the research prospect on this field is explored.
Dynamic Model of Wind Speed Longitudinal Component
Authors: Sarsikeev Yermek , Lukutin Boris V. , Lyapunov Danil Yu. , Surkov Mikhail A. , Obuhov Sergey G.
Published: June 2014

The paper deals with the development of the dynamic model of wind by modeling the longitudinal component of wind speed. Statistical description of turbulent wind component using Kaimal’s function is represented. All necessary parameters for model performing are calculated. The results of modeling in the form of dynamic characteristics are presented.
Distributed Wind Power Integration Operation and Impacts on Regional Power System
Authors: Li Guang Lei , Shi Xin , Zhang Chun Xu , Deng Hua , Zeng Xian Zhen
Published: June 2014

At present, distributed wind is in its infancy, so engineering practice and related technology research and development is relatively lacking. The aging problem parallel operation between wind power and power grid enterprises is the issue that the whole world should be confronted with. This paper study the influence of wind power access to power grid operation, reveal the interactive mechanism of distributed wind power and power grid, formulate the corresponding technical specification and achieve the centralized control of distributed wind power. These can be used to guide the large-scale development of distributed wind power, which makes the development of distributed wind power guided by resource type guide transition to the grid type.
A Probabilistic Load Flow Method Based on Markov Chain Wind Power Prediction
Authors: Deng Wei Si , Zhang Bu Han , Ding Hong Fa , Wang Ke , Zeng Dan , Zhang Kai Min , Shao Jian , Ge Teng Yu , Jin Bing Jie
Published: June 2014

With the wind power installed capacity increased, it brings great challenges to the stable operation of the power grid. In order to take consideration of the wind power impact, this paper proposes a wind power variability model applied to the probabilistic load flow calculation using the method of combined cumulants and improved Von-Mises Expansion. This wind power variability model combines the concept of Markov chain process and scenario tree theory, taking in to account the relationships of the outputs of wind turbines at adjacent moment by considering the coupling interaction at different time intervals. Computer simulations verify the effectiveness and applicability of the proposed method through IEEE bus-39 New England case study.
Dynamic Economic Dispatch of Wind Power Incorporated System
Authors: Bie Pei , Wei Zhong Kang , Zhang Bu Han , Xing Jing , Zhao Shuang , Li Mei , Zeng Yuan Fang
Published: June 2014

Wind energy source has been paid high attention to and developed into one of the most mature and largest-scale mode of new energy power generation. However, the uncertainty and fluctuation of wind power brings great challenge to the normal operation of power system. In this paper, the dynamic economic dispatch of wind power incorporated system is demonstrated. The accumulation variable method based on chance constraint programming is adopted to make the dynamic economic dispatch. The test example shows that the accumulation variable method based on chance constraint programming is suitable and effective.
Research of Wind Power Plant Risk Management Based on Bayesian Network
Authors: Yang Shuang
Published: June 2014

This paper aims to put forward a wind power plant risk management model, using bayesian networks, not only suitable for the project risk management, also useful for subsequent projects. For other construction enterprise risk management problem has great reference value.
Simulation of PV and Wind Hybrid Power System
Authors: Hua Ze Jia , Wu Jing , Mi Ze Ya , Zhu Jia Lei
Published: June 2014

The PV and wind hybrid power system uses the front-end DC-DC conversion circuit, the system's overall output power is unified deployment and controlled, through elaborating the component characteristics and assessing mathematical model of the actual obtained, more accurately determines operation condition of the system per hour. The system energy analysis of flow and motion makes the system in dynamic change switch from the different forms of work patterns and operation, completing the corresponding control, so as to realize the optimization of system and reliable operation.
Chemical Speciations of Uranium of a Sandstone Uranium Deposit and their Effects to In Situ Leaching, Northwest China
Authors: Chen Liang , Li Yong Feng , Tan Kai Xuan , Hu Yang , Xie Yan Shi , Huang Wei , Wang Zheng Qing
Published: June 2014

The chemical speciations of uranium of a sandstone uranium deposit in the Yili Basin were quantitative analyzed using the method of sequential chemical extraction, and the implications of which for in-situ leaching of uranium were discussed. The proportion of chemical speciations of uranium shows that the bound to carbonates>the bound to Fe-Mn oxides>the exchangeable>the residual>the bound to sulfide-organic matter speciation, which is beneficial to cost reduction on in-situ leaching of uranium and environmental protection. The active uranium includes 4 chemical speciations except for the residual speciation is principal, which suggests that the leaching rate of uranium of the sandstone uranium deposit is high. The inert uranium is the residual speciation, with low proportion. The sample with high proportion of active uranium is of high grade, and vice versa, which indicates that the ratio of total uranium extracted/reserves should be relatively high. Hence, based on the chemical speciations of uranium, the sandstone uranium deposit can be exploited suitably using the technique of in-situ leaching with dilute sulfuric acid, integrated considering that cost control of in-situ leaching of uranium, environmental protection, leaching rate of uranium and the ratio of total uranium extracted/reserves of uranium.
The Impact of Primary Circuit Coolant Average Temperature on the Secondary Circuit Thermal Efficiency at Nuclear Power Station
Authors: Wang Sheng Long , Li Tong
Published: June 2014

The variations of secondary circuit parameters are limited by the parameters of primary circuit during PWR nuclear power station operation, the primary circuit average temperature should vary at the range of nuclear reactor operating safely. In the existing analysis of secondary circuit thermal efficiency at nuclear power station, the impact of primary circuit average temperature on the secondary circuit thermal efficiency is not taken into consideration. In this paper, the changes of primary circuit average temperature in actual operation are considered, the secondary circuit parameters are calculated according to the model of heat flux transfer between primary and secondary circuit, the thermal efficiency of ideal cycle is chosen as the evaluating indicator of secondary circuit thermal efficiency, the thermal efficiencies of ideal cycle in secondary circuit are calculated under the conditions of varying coolant average temperature with the method of matrix, and the calculated results are basis for the safe and economic operation of nuclear power station.
Study on the Difference between ORIGEN-S and ORIGEN2
Authors: Chen Hai Ying , Wang Shao Wei , Guo Rui Ping , Lan Bing , Zhang Chun Ming
Published: June 2014

The ORIGEN-S and ORIGEN2 codes were described in this paper, which were used to calculate the source term in the reactor core. The differences between ORIGEN-S and ORIGEN2 codes were compared and analyzed. The most significant difference was the methodology used to prepare and provide the neutron data for the codes, which directly affected the accuracy of calculation results of the ORIGEN2 code under different values of the parameters. Finally, the radioactivity of the actinide and fission products was calculated by changing the fuel enrichment, burnup and specific power of PWR, which was used to make quantitative analysis of the difference of results calculated by ORIGEN-S and ORIGEN2 and verify the degree of influence of various parameters on the results.
Theoretical Calculation and Numerical Investigation for the Effective Thermal Conductivity of Packed Li2TiO3 Pebble Bed
Authors: Cao Hao Ran , Huang Rong Hua , Li Jun Heng
Published: June 2014

Lithium titanate (Li2TiO3) in form of packed pebble bed is promising concept for breeder material in the fusion reactor blanket, and worldwide efforts have been dedicated to its R&D in the last two decade. Li2TiO3 pebble beds with the efforts of tritium breeding and thermal removing play a major role in the thermal performance of the fusion reactor blanket. Specifically, the effective thermal conductivity of Li2TiO3 is an important parameter for the design and thermal mechanical of fusion reactor blanket. The theoretical calculation and numerical simulation for the effective thermal conductivity of Li2TiO3 pebble bed are performed in this paper. The theoretical equations and modeling result for the thermal conductivity of Li2TiO3 pebble bed are given and compared with the experimental data. The results show that the effective thermal conductivity of Li2TiO3 pebble bed can be preliminarily obtained by numerical simulation and theoretical calculation.
Analysis on the Technical Solutions of the Heat Source of the Geothermal Heat Pump System
Authors: Tan Chao Yi , Zhu Hui , Hu Hai Hua , Wang Meng Meng , Wang Han Qing
Published: June 2014

Taking the geothermal heat pump system in the campus of Hunan University of Technology for example, three technical solutions of the heat source of the system were analyzed in terms of the condensing heat load, the annual unbalanced heat load and the energy efficiency ratio (EER) of the system. In addition, comparison was conducted among the solutions. The results indicate that the solution 3, which has a cold and hot water integrative unit and hot water unit connected in series, meanwhile has a cooling tower for auxiliary cooling, shows better performance among all the solutions. The analysis on the solution of heat source of geothermal heat pump system, which usually contains the analysis on the condensing heat load, annual unbalanced heat load and EER, is of great significance for the design and development of the geothermal heat pump system with lower coat and higher EER.
On Mathematical Modeling of Piezoelectric Energy Harvesters
Authors: Shang Guang Qing , Wang Hong Bing , Sun Chun Hua
Published: June 2014

Energy harvesting system has become one of important areas of ​​research and develops rapidly. How to improve the performance of the piezoelectric vibration energy harvester is a key issue in engineering applications. There are many literature on piezoelectric energy harvesting. The paper places focus on summarizing these literature of mathematical modeling of piezoelectric energy harvesting, ranging from the linear to nonlinear, from early a single mechanical degree to piezoaeroelastic problems.
Application Analysis of Heating Mode of Geothermal Direct Supply Combined with Water Source Heat Pump in Bohai Oil Base
Authors: Wen Guang Lian
Published: June 2014

Based on the geothermal resources condition and the situation of original heating system in Bohai oil base, this paper presents the application analysis of heating mode of geothermal direct supply combined with water source heat pump from the aspects of energy saving, environmental protection, operation cost reduction, and protection of resources. It is found that the new heating mode is applicable. Furthermore, this paper provides the suggestion for further energy saving.
Design of a Solar Assisted Absorption Refrigeration System
Authors: Liu Yan Ling , Shi Xue Zeng , Yu Yuan
Published: June 2014

This paper presents the design of a solar/gas driving double effect LiBr-H2O absorption system. In order to use solar energy more efficiently, a new kind of solar/gas driving double effect LiBr-H2O absorption system is designed. In this system, the high-pressure generator is driven by conventional energy, natural gas, and solar energy together with water vapor generated in the high-pressure generator, which supplies energy to the low-pressure generator for a double effect absorption system. Simulation results illustrate that this kind of system is feasible and economical. Economic evaluation of several systems is also given in this paper in order to get a clear knowledge of the energy consumption of the system.
Performance and Exergy Analysis of Open Absorption Heat Pump
Authors: Wei Fan , Zhang Shi Jie , Xiao Yun Han
Published: June 2014

An open absorption heat pump(OAHP) in second type was built in this paper in order to recycle the heat and water from the flue gas. the coefficient of performance(COP) and the exergy efficiency were analyzed with the method of process simulation. Results showed the COP is 0.64, and latent heat recovery ratio is 19.6%. The temperature and humidity of flue gas, the temperature and flowrate of cooling water would influence on the COP. The increase of these parameters would lead to COP increase. The exergy efficiency of the system was 19.2%. The absorber, the generator and the condenser produce most exergy loss. The exergy efficiency of condensation was 0, which was using to recovery condensation water. The exergy efficiency would be strengthen by reducing the exergy loss of absorber and generator.
Research on Optimization of Ground-Coupled Heat Pump Systems under Specific Constraint Conditions
Authors: Wang Yang Yang , Hu Ping Fang , Lei Fei , Zhu Na , Wu Tian Hua , Yang Feng
Published: June 2014

A design method for ground-coupled heat pump (GCHP) systems with specific constraint conditions is proposed. The total borehole number, borehole depth, borehole space and average velocity of fluid in the U-tube are considered as variables in the optimization problem. The optimization problem of four variables is transformed into that of single decision variable. A case study, which includes different schemes for designing GCHP systems of an office building and the corresponding economic analysis, is performed with the aid of simulation software. The result shows that optimal design parameters could be found in an economic optimization problem with specific constraint conditions. Additionally, design parameters may have a notable influence on the energy consumption of circulating pumps. The optimization method in this paper could be utilized by engineering designers for reference.