bluuebunny/crossref_metadata_2025 huggingface dataset:
Investigation on Type-4 and Type-11 Mixed Topology of LLC Resonant Converter
Authors: Yan Xiang Wu , Sun Lei , Zhang Bo , Lv Zheng
Published: June 2014

LLC resonant converter can adjust the output for a wide range of source and load with a small fluctuation of switching frequency, so it is used widely. This paper introduces all arrangements of LLC topological group, then proposes a new topology which is consist of Type-4 and Type-11 that used widely,in this paper we also give its calculate method of resonant frequency. Lastly we get gain characteristics of the topologies in the PSpice simulation environment and analyse the influence factors on adjustment ability in certain load range .
Study of a Small-Scale Controllable Reactor and Conceptual Design of a 35kV/5Mvar HTS Reactor
Authors: Xu Ying , Ren Li , Tang Yue Jin , Song Meng , Li Jing Dong , Shi Jing , Dong Hong Da , Cao Kun Nan
Published: June 2014

Since Ultra High Voltage (UHV) transmission lines have the high charging capacitance, continuous reactive power compensation is vital for efficient operation of long transmission power lines or cables. A continuous reactive compensation will reduce the transmission losses and increase the transmission capacity of active power. In order to achieve the continuous reactive power compensation, we choose the magnetic saturable type reactor. The principle of a magnetic saturable reactor requires a high current ampere-turn coil as its dc bias, and this coil is necessary to use a high temperature superconducting (HTS) winding. As the first stage of the study, we have constructed a 220V small-scale prototype which the dc bias is made of copper coil instead of the HTS coil. The copper coil of the dc bias in small-scale reactor has the same ampere-turn with a 220V HTS controllable reactor (HCR), so its performance keeps the same except the HTS part. Based on this, we made a conceptual design for a 35kV/5Mvar HCR. The output property and harmonic property have been studied by simulation and experiment. The results prove that it can obtain a continuous controllable reactive power output.
A Flyback Switching Power Supply Based on L6561 for LED
Authors: Shao Zhu Lei
Published: June 2014

A flyback switching power supply was designed, which can drive LED stability. The switching power supply is the single-ended flyback structure, and based on PWM driver chip L6561. The input voltage range of the switching power supply is 85V to 265V. The output voltage is 15V and the maximum output current is 2A. The switch power supply is suitable for mobile phone, office equipment and LED. According to experiment, the switching power supply can steadily drive 5 LED, the ripple factor of output is 1.33%, the power efficiency is 85.7%.
Micro-Grid Inverter AC Side Load Voltage Stability Control Based on SVPWM
Authors: Zhang Wei Lin , Shi Peng Fei , Gu Yu Jiong , Zhu Ping
Published: June 2014

Space vector pulse width modulation (SVPWM) technology can significantly reduce the harmonic content of the inverter output voltage and increase voltage stability compared to other modulation techniques. This paper apply the SVPWM technology in the micro-grid inverter side load voltage stability control, on the basis of dual loop vector inverter control and the basic principles and algorithms of SVPWM. The MATLAB/Simulink simulation show that the response based on SVPWM inverter system changes very rapid load ,the AC side load voltage and frequency control is also very stable.
Low Frequency Oscillation Analysis of Microgrid Using Perturbation Theory
Authors: Xia Bing Yang , Ma Jing
Published: June 2014

This paper presents a perturbation based method for small-signal stability analysis in microgrid based on the uncertainty of microgrid parameters. The small-signal state-space model is built including the dynamic characteristics of the controllers, the power measurement and the system circuit and load dynamics model. The system eigenvalues of operating point at a steady-state in microgrid are obtained by the model. Based on perturbation theory, the corresponding low-frequency eigenvaluea and damping ratio of the microgrid system are calculated when the microgrid parameters changing in the range. Then the relationship between small-signal frequency stability and parameters changes can be determined. The validity of the proposed method and the importance of the stablility analysis of the microgrid small-signal are proved by the simulation results.
Design of Locomotive Energy Consumption Monitoring System
Authors: Yu Hui Jun , Zhou Zhi Wei , Chen Cai Biao , Gu Ju Hui
Published: June 2014

The paper introduces the structure of locomotive energy consumption monitoring system, technical parameters and the method of software design. The system uses electric energy metering chip CS5463, ARM kernel STM32F103R8T6, GPRS wireless communication module and RS485 communication interface to realize the multi-system locomotive AC and DC measurement, remote meter reading and other devices and locomotive communication connection. The liquid crystal display LCD stores the locomotive power information, the current, voltage, power and energy data with their own real-time clock time-sharing data fragmentation such as type test on the system, the system of high precision, strong anti-interference ability, low power consumption, safety etc.
Research on Governor-Side Power System Stabilizer
Authors: Pan Feng Ping , Zhong Min , Chen Yu Zhen , Zhu Ya Qing , Chen Shi He , Zhang Xi , Luo Jia
Published: June 2014

By analyzing the control principle of power system stabilizer (PSS),shows that the robustness of PPS is not ideal. Using the methods of state-space pole placement designed the governor-side power system stabilizer GPSS,and built a simplified model of the power system with simulink. The simulation experiment results made ​​in the MATLAB shows that GPSS has good inhibitory effect of low-frequency oscillations.
Manufacture and Experimental Investigation of a Multi-Layer Generator Based on Dielectric Elastomer
Authors: Liu Xue Jing , Zhang Gong , Wang Yong Quan , Jia Shu Hai
Published: June 2014

As a member of Electroactive Polymers (EAPs), dielectric elastomer (DE) has shown considerable potential for energy harvesting applications. After the basic principle of DE energy harvesting is studied, a multi-layer DE generator using VHB 4910 (3M, USA) is specially designed and fabricated. Then, an improved energy harvesting circuit is designed to make use of harvested electrical energy. Finally, energy harvesting experiments are implemented under the constant charge (open-circuit) condition and the results prove that the multi-layer DE generator fabricated can produce enough energy to constantly drive a light emitting diode. The harvested electrical energy has good consistent with generated electrical energy and the maximum energy harvesting efficiency ηh can reach 89%.
The Simulation Study on Dynamic Characteristics of COGAG Engaging Process
Authors: Meng Hui , Wang Zhi Tao , Li Shu Ying , Zhao Ning Bo , Jin Gang
Published: June 2014

This paper establishes the COGAG system simulation model in the environment of SIMULINK and ADAMS with the method of coupled simulation based on multiple simulation platforms; simulates and analyses the COGAG engaging process with the simulation model. Dynamic change rules of some key parameters such as speed, moment, power are obtained and analysed detailed, which plays an important role in development and application of COGAG device.
Enchanted Multi-Objective Differential Evolutional Algorithm for Economic/Environmental Dispatch
Authors: Sun Peng , Luo Ming Wu , Sun Chao Xia
Published: June 2014

An enchanted multi-objective differential evolutional algorithm was proposed, and was applied to solve the environmental economic dispatch problem. Duo to the weakness of random initial population, the orthogonal method was used in the initialization. Based on survival of the fittest, improved differential operation was proposed, combined with the corresponding parameters control method proposed. With the combination of B-coefficient method and restrain dominance, the process of solving equation and selection operation were used to make the individuals meet the equality constrain. Then the algorithm was tested on the IEEE-30 test system, the results are compared with the results of non-dominated genetic algorithm-II、multi-objective differential evolution and the known results in the papers, and the validity is verified. Keywords: Security constrained economic/environmental dispatch,Constrained multi-objective differential evolution,Feasible region and infeasible region
Urban Power Supply System Risk Assessment
Authors: Si Qing Min , Zhang Xing Bai , Jiang Xue Ying , Tian Lei , Yu Gong Xin
Published: June 2014

Urban power supply system has close relationship with urban public safety. The main risk factors, accident types and the risk degree of failures or accidents in urban power supply system are analyzed. And, it has established the public safety risk assessment system of urban power supply system. In order to show that the assessment system has good applicability in the risk assessment of urban power supply system, the power supply system safety of one urban is assessed using established risk assessment system.
Corrosion Resistance of CrSiN Coatings by Cathodic Arc Deposition with Different Arc Currents
Authors: Ho Wei Yu , Tsou Po Yi , Chang Yen Shuo , Lin Cheng Liang
Published: June 2014

Bipolar plate with multiple functions is one of the essential components of the PEMFC (Proton Exchange Membrane Fuel Cells) stacks. Recently, metallic bipolar plates, particularly different grades of stainless steels, have been increasingly considered due to relatively low cost, good corrosion resistance, sufficient stiffness and excellent flexibility in thin forms, and easy manufacturability [1-3]. However, the major concerns with the use of stainless steel alloys as bipolar plates are their corrosion resistance and interfacial electrical resistance under long operation conditions. Development of advanced ternary nitride coatings such as chromium silicon nitride (CrSiN) has attracted significant industrial interest in recent years [4-11]. Si addition of CrN to form CrSiN films were prepared by cathode arc ion deposition technique and magnetron sputter technique, in order to improve the characterizations of the coatings from structure to corrosion behaviors. It is reported that with the additional element of Si, the hardness and corrosion resistance of the CrSiN coatings can be greatly improved compared to that of the CrN coating. A direct link between the microstructure and mechanical properties of CrSiN coatings with varying Si contents was established [8]. With increasing Si content, the structure of CrSiN coating exhibited the transformation from a columnar-grained structure to a nanocomposite structure, consisting of CrN nanocrystallites embedded in an amorphous matrix. A maximum hardness of 26.6 GPa was found for CrSiN coating with Si content of about 6.7 at.%, while that of pure CrN was 19.4 GPa [6]. Up to now, the CrSiN is yet thoroughly investigated.
Review on Business Operation Mode and Technical Economy Evaluation of Micro-Grid
Authors: Liu Jie , Liu Nian
Published: June 2014

To make the advantages of smart micro-grid in economy and environment to the greatest extent, many countries choose to make detailed research on the business operation mode and technical economy of micro-grid. Based on the related research, this paper generalizes several typical user modes, and then provides a reasonable technical route to study the operation mode and technical economy of micro-grid. For its business operation mode, not only the existing proposals are analyzed, but also are its method of calculating the cost and benefits of this program. Finally, specific plans about how to assess the technical economy are also analyzed.
Research on Comprehensive Assessment Index System for Transmission Network Planning Alternatives
Authors: Lin Yong , Li Zuo Hong , Dong Mei Ling , You Da Hai , Wang Gang , Chen Wei Hua
Published: June 2014

In view of the lack of comprehensive and quantitative evaluation means for transmission network planning currently, a comprehensive assessment index system adapted to the characteristics of the transmission network planning is proposed, including 6 strategic layer indices (safety and reliability, economic efficiency, flexibility and coordination, smart and green, controllable risk and social benefits), 16 target layer indices and 57 operating layer indices. And the assessment standard for each index is determined to provide objective, comprehensive and systematic evaluation of transmission network planning alternatives as well as prepare for realization of the comprehensive evaluation of transmission network planning.
Synthesize of Mesoporous ZnO Thin Films and Gas Sensing Property
Authors: Hong Min Hee , Choi Yong June , Lee Tae Won , Chung Hee Yoon , Park Hyung Ho
Published: June 2014

In this work, ordered mesoporous ZnO thin films was synthesized and gas sensor properties were introduced. Mesoporous ZnO thin films were successfully formed by sol-gel process. In ZnO structure, complex agent (MEA) was used for the hydration and condensation reaction. According to the change of MEA concentration, porosity and pore arrangement, specific surface area could be changed. As complex agent concentration decreased, pore ordering was increased and gas sensitivity has the high value (8.01).
The Relationship among the Security, Efficiency and Adequacy of Electrical Power Grid Based on the Novel Evaluation Method
Authors: Long Wang Cheng , Han Feng , Zhang Xue Ming , Peng Dong , Li Hui
Published: June 2014

In order to study out the incidence relationship among security, efficiency and adequacy of Electrical Power Grid, a novel analyze model considering grid evolution and a relationship evaluation method is proposed in this paper. The model incorporates in fast dynamic and slow evolution. The former is based on an improved OPA model with low frequency load shedding control and the outage risk calculation. The latter is consists of increasing load, up-grading and constructing equipments including power plants, transformers and transmission lines, Using the model simulation the power grid development process. Based on the model, the customer outage risk caused by cascading failure is obtained in several times, the efficiency index and grid scale index are solved at the same times, these data are the basic data for analyze the incidence relationship among the security, efficiency and adequacy of electrical power grid. In this paper, the power grid of Kaifeng City in Henan Province, of China is used to simulate the evolution. The results show that the relationship among the security, efficiency and adequacy of grid is as exponential function, and a reasonable range of efficiency and adequacy of grid are proposed.
Crack Growth Features in Hydrogenating High-Strength Steel AISI 4340 under Cycling
Authors: Shashurin Georgy V. , Tarakanov Pavel V. , Rezchikova Ludmila A.
Published: June 2014

There are various types of structural components, which are subjected to hydrogen aggressive environment and cycling. Their unexpected failure occurs suddenly and may entail serious consequences such as emergency stop of equipment, failure of the structure etc. The special engineering models are developed to predict the crack kinetics in structure components, which are subjected both to hydrogen environment and to cycling simultaneously. These models enable estimation of structure component life. The paper considers some features of such empirically specified special model giving emphasis to the one of them, namely to the prevailing fracture mechanism transition from fatigue to hydrogen embrittlement and back in crack kinetics process.
Research on the Mobility of Polymer Flooding System for Xinjiang Conglomerate Reservoirs
Authors: Wu Yun Qiang , Lou Qing Xiang , Nie Xiao Bin , Li Yi Qiang , Xiang Jia Nan , Miao Jun Jie
Published: June 2014

The conglomerate reservoir is provided with strong heterogeneity and complex pore structure. To study the matching relationship between polymer flooding system and pore throat of the conglomerate reservoir and set up the flow matching relationship plate, this paper conducted natural core flow experiments at the true flow rate of the site formation based on constant pressure flooding method, considering the shear of the borehole and the formation. And several suitable polymers for different reservoirs permeability were given. The experimental results indicated that a positive correlation between the flow properties and the viscosity of the polymer solution, but a negative correlation between the mobility and the permeability of reservoir. Such as the natural core with the permeability = 30×10-3μm2 was suitable for the viscosity≤16.0 mPa.s of the polymer solution in the formation, the natural core with the permeability = 60×10-3μm2 was suitable for the viscosity≤35.2mPa.s of the polymer solution and the natural core with the permeability = 120×10-3μm2 was suitable for the viscosity≤102.4mPa.s of the polymer solution. Using compatibility relationship, quickly and easily choose the right injection parameters of the polymer based on the reservoir permeability, providing a theoretical basis for program preparation and parameters adjustment of the polymer flooding.
Rheological Properties of Sodium Metatungstate in Aqueous Solutions
Authors: Ku Jian Gang , He Kui , Chen Hui Huang , Liu Wen Yuan
Published: June 2014

Sodium metatungstate (SMT) solution is an inorganic heavy liquid which is widely used in density fractionation. However, rheological properties of aqueous SMT solutions have never been fully researched. The objective of the present work was to study the rheological properties of aqueous SMT solutions and effects of temperature and density on the apparent viscosity. The steady flow experimental data was fitted using Herschel-Bulkley model. The results show that aqueous SMT solutions of different density are pseudoplastic fluids and the flow curves of SMT solutions were described by the Hershel-Bulkley equation. The apparent viscosity decreases monotonically with increasing temperature under the same density and increases exponentially with increasing density at the fixed temperature. Rheological properties of aqueous SMT solutions can be applied in the calculation of density fractionation efficiency and provides a theoretical basis for flow simulation.
Fluoroimmunoassay Based on FITC-Labeled Antibody for the Determination of Estradiol
Authors: Wang Long Jun , Xue Wei Li , Du Ling Yun
Published: June 2014

A new fluorescence immunoassay with high sensitivity, time-saving, good precision and reliablility was proposed for the determination of estradiol (E2) in human urine. The complex of FITC-labeled anti-E2antibody was produced and regarded as a probe in this system. Ninety-six microplate was coated with ovalbumin conjugated E2antigen as solid phase for the immunoassay. The method parameters affecting the determination, such as the concentration of immunoreagents, pH, and other relevant variable conditions upon the immunoassay were studied and optimized systematically. Under the optimal experimental conditions, it was found that the proposed method exhibited high performance with the detection limit of 9.2 pg/mL, and the linear range of determination of 0.01-1000 ng/mL. The recoveries were 93.58-105.82% with the relative standard deviations (RSD) 5.52-7.09%. The proposed method has been used for the determination of E2in human urine with satisfactory results, and may be expected to find wide application in other environmental samples.
Thermal Transport in Hotspots Using the Lattice Boltzmann Method with Application to Silicon-on-Insulator Transistors
Authors: Mao Yu Dong , Xu Ming Tian
Published: June 2014

Silicon-on-insulator (SOI) transistors have been widely used in the micro-electronic devices. The Lattice Boltzmann method (LBM) is employed to simulate the heat conductions of hotspots appeared in a SOI transistor. The results show that a thermal wave effect is appeared in micro-region, and it can not be found in Fourier prediction. Comparing the results obtained by the Fourier law and LBM, we find that the LBM solution shows approximately 22% higher energy density than the Fourier prediction. When two thermal waves form different hotspots meet together, a significant energy enhancement will be appeared.
Research on the Initial Features and Spreading Rules of Large Scale Oil Fire
Authors: Jiang Xin Sheng , Sun Guo Jun , He Biao , Ou Yi Hong , Wang Dong , Zhou Jian Zhong
Published: June 2014

The initial features of large scale oil fires were studied through combustion experiments in oil basins. Four basins were prepared, the diameters of two of them were 2.5m, and another two were 2m. Oil in the basins was ignited simultaneously, and the experiments were conducted twice. The thermal radiation, temperature distribution and components of pollutants were detected and analyzed. Then, some initial features and instructive rules of large scale oil fire disasters were concluded. Known from the experiments, the temperature is high in center areas and low around, in the vertical direction the temperature is high both in upper part and bottom and low in the middle. In addition, the density values of gas pollutants sampled during the experiments can reach to several hundred times of the standard values.
Dependence of the Distribution Law Parameters of the Annual Run-Off of Rivers in Primorsky Region on the Soil Thermal Conductivity
Authors: Lobanov S. A. , Kholoden E.E.
Published: June 2014

The empirical investigation of the dependence of the statistical characteristics of annual run-off of Primorsky region rivers - modulus of flow, variation coefficient, asymmetry ratio, polymodality degree – on the weighted average values of the soil thermal conductivity coefficients within their watershed areas was carried out. The physico-statistical interpretation of the general form of correlation dependences obtained is provided.
Integrated Flat Plate Heat Pipe-Pulsation Heat Pipe for the High-Flux Electronics Cooling
Authors: Zhang Ya Ping , Wang J.G.
Published: June 2014

A trend towards increasingly dense and compact architectures has led to unmanageably high heat fluxes in electronic components. A novel heat pipe will be developed. Heat pipe designed is based on the flat plate heat pipe and pulsation heat pipe effective combination. Channel quantity is greatly increased ,as well as compact and homogeneous red copper pulsation plank is severed as the wick，dense and connected channels are served as the passage of the working fluid.
Optimum Design of Flexible Microwave Absorption Fabrics
Authors: Wei Sai Nan , Li Qian , Yao Ji Ming , Cui Rui Fang , Sun Tian
Published: June 2014

In order to develop flexible absorption fabric and study the effects of specifications on absorption properties, two-layer laminated fabrics were designed according to thickness matching and impedance matching. Stainless steel core-spun yarn fabrics were used as first layer which easily realized matching to the free space, Ni-Fe fiber consisted of second layer because its strong dielectric loss and magnetic loss. The reflectivity of fabrics were measured by the means of "arch testing method" in the range from 2~18 GHz. The results showed that the reflectivities of laminated fabrics can below-20 dB and the bandwidth <-10dB can reach 3.88 GHz with the change of fabric specifications.
The Experiment for Vertical Rectangular Micro-Channel Flow Boiling
Authors: Li Dian Xun , Zhang Shu Sheng
Published: June 2014

To further deepen exploration of boiling in micro-channels a set of experiment system for micro-channel flow boiling is homemade, which includes experimental equipment required and experimental pieces of the design process. The channel is width of 100mm, length of 1200mm, and the groove depth of 95mm. The gasket thickness is 0.5mm, 1.0mm, 1.5mm or 2.0mm.
Preparation of SiO2–TiO2 Nanocomposite and Its Application on Elemental Mercury Removal in Simulated Flue Gas
Authors: Shi Xue , Ni Bu , Li Chao En , Li Xian , Zhang Chong , Hu Tao , Wu Jiang
Published: June 2014

SiO2–TiO2 nanocomposite was synthesized by an ultrasound-assisted pure physical method to oxidize elemental mercury (Hg0) in simulated flue gas. Due to its low cost and photocatalytic ability, SiO2 was used to dope TiO2 to modify the TiO2 photocatalyst. We put different ratio of TiO2 / SiO2 under the UV irradiation to get a low Ti/Si doping ratio and high flue gas mercury removal efficiency of SiO2–TiO2 nanocomposite catalyst. It was found that the photocatalytic activity of nanocomposite materials did not significantly improve, or even decline. This is mainly because that the presence of too much porous SiO2 may affect TiO2 on the effective absorption of light and direct adsorption of contaminants. When Ti: Si ratio was 2:1, SiO2–TiO2 nanocomposite catalyst reached its highest elemental mercury removal efficiency in the simulated flue gas.
Impact of Changing Combustion of Shenhua Coal to Boiler Operation
Authors: Sun Yi Peng , Cheng Liang , Zhang Qing Feng
Published: June 2014

Experimental study of changing and blending combustion of Shenhua coal on boiler operation was carried out, while the furnace slagging during the experiment, the coal pulverizing system adjustment and the boiler operation oxygen control issues were analyzed. The results show that: the boiler can operate in safety blending Shenhua coal and Zhungeer coal with the ratio of 7:3 based on the strengthening laboratory analysis of coal as fired, the safety and economy of the boiler and coal pulverizing system can be ensured with the pulverized coal fineness R90 in 30%, and selecting the lower mill combinations and setting the coal pulverizer outlet temperature at 73°C, the reasonable exhaust gas oxygen content should be 4.0%, and the boiler thermal efficiency has an 1% increase compared with the condiation of burning inferior Shanxi bituminous coal, the nitrogen oxide emissions are significantly reduced.
Experimental Research of Heat Transfer Enhancement of the Tube with Disturbed Flow Components Plug-In
Authors: Ji Chang Fa , Qu Rui , He Guo Xin
Published: June 2014

Based on Field Synergy Principle and orthogonal experiment design, nine arranged metal-wire inserts(that is high porosity porous inserts) is determined to experiment. The results showed that heat transfer performance of the pipe that metal-wire inserts is rooted at the core region of pipe is better than the pipe that metal-wire inserts is rooted at the edge region of pipe., location and curve radian can impact heat exchange significantly. Under the given experimental condition, the heat transfer quantity increased by 120 - 520%, overall heat transfer coefficient increased by 126 - 610%. Through enhancing heat transfer performance evaluation criterion (PEC) comprehensive evaluation, it is concluded that when the Reynolds number Re changes in 338 ~ 6931, the PEC value of 0.89 ~ 5.97.The calculation formula of the drag coefficient is obtained by regression analysis.
Development of a Condensation Refueling Gas Recovery System Based on Turbo Brayton Refrigeration Technique
Authors: Xiong Lian You , Lu Wen Hai , Huo Zhi Yong , Peng Nan
Published: June 2014

Volatile organic compounds (VOCs) are emitted from the refueling of gasoline vehicles and trucks. Controlling these emissions has been an important issue since the late 2000s in China. We have recently developed a condensation refueling gas recovery system to recover the VOCs from gaseous wastes at a bulk gasoline terminal. In this system VOC vapor is condensed by a reversed turbo-Brayton cycle refrigerator. The recovery system has a capacity of 100 Nm3/hr at the lowest condensation temperature of 190K. It has been put into use since 2008. The achieved recovery efficiency is 96% and the emission of VOCs is less than 8 g/m3 at the exit of the recovery system.
Numerical Analysis of Air Measuring Station Location Optimization in Underground Mine Airway
Authors: Zhang Jing Zhao , Yan Yong Sheng , Yan Zhen Guo , Wu Feng Liang
Published: June 2014

The optimized air measuring station location of mine airway based on air fully developed was proposed and numerical tests were conducted with six models. The independence of air fully development and inlet velocity was analyzed which validated the models and the numerical methods. The results show that optimized air measuring station location in head entry is 132m-198m after the airway turning while 5.0m-10.1m before the airway turning in tail entry.
The Analysis of Comfortable and Energy Saving of Ice-Storage Low Temperature Air Supply System
Authors: Bai Li , Zhou Xue Zhi , Wang Yan , Hua Ya Wei
Published: June 2014

More and more attentions have been paid on ice-storage low temperature air supply system because of its notable energy saving effects and comfort. The paper expatiate on that ice-storage low temperature air supply system brings a series of especial superiority to modern air-condition cause. The results show that low temperature air supply system can exert the potential advantage of ice-storage further. The combination of ice-storage and low temperature air supply system can obtain an “integrated approach”, which can save energy resources and improve human body comfort and indoor air quality.
Model Investigation on Coupled Throttling Flow Characteristic of Stepped Capillary Tube with R22
Authors: Xu Yan Sheng
Published: June 2014

In order to calculate the structure size of stepped capillary tube, the experiments of flow characteristic of it were performed. The experience benchmark model of flow characteristics of R22 was set up through experimental method in specific reference conditions based on the impedance calculation method. The variable working condition model suitable for a range of conditions was obtained through fixing the condition based on the reference model. The mass flow rate of refrigerant R22 in two stepped capillary tubes with different size was tested. The experimental results show that the stepped capillary tube model has a high precision and working condition of certain flexibility. The deviation of cooling and heating flow between the calculated values and measured values are less than±10%. The model can meet the need of matching for stepped capillary tube on the heat pump type air conditioner with R22.
Gas Load Characteristics and Calculation
Authors: Zhao Lei
Published: June 2014

Gas Load Characteristics of different users are analyzed in this paper. Different types of load charts which is drawn according to the statistical data may provide certain guidance for gas companies. Non-uniform coefficient method that continues to be used for calculation of gas load in China has limitations. It is more reasonable to calculate gas load with load coefficient method.
The Design of a New Signal Handing Circuit of Seismic Geophone
Authors: Li Liang , Tuo Xian Guo , Mao Xiao Bo , Liu Ming Zhe
Published: June 2014

This paper aims at the problem that how to elimination the DC component of the MEMS geophone in the acquisition and processing of Seismic signal. Put forward to design a new circuit in the signal handing system. Design a new type of DC elimination circuit to eliminate the DC component through low-pass filter, reverse and other modules. The experiment result shows that, this new DC elimination circuit is easier to realize and has a large advantage than other existing DC elimination circuits.
Cubic Spline Interpolation Method for the Envelope Tracking of Middle and Low Frequency Voltage Flicker
Authors: Jia Xiu Fang , An Hai Qing , Zhang Shao Guang
Published: June 2014

Flicker envelope tracking is the key of analyzing voltage flicker signal. A novel method, i.e., cubic spline interpolation method is applied in the detection of the voltage flicker envelope. The typical flicker signals, such as one or multi-frequencies and frequency time-varying flicker signal are selected and analyzed by this method. Simulation results indicate that this method is effective in the detection of the envelope of voltage flicker signal. Results of one or multi-frequencies flicker signal simulation show that, when flicker frequency is less than 15Hz , the error of this method is quite tiny. The detection precision of this method is higher, especially in the scope of low frequencies of flicker and this method makes up for the disadvantage of square demodulation. Furthermore, results of frequency time-varying flicker signal simulation show that, the occurrence and recover time of voltage flicker signal can be accurately detected by cubic spline interpolation method.
Partial Linear Method for Background Harmonic Voltage Estimation
Authors: Jia Xiu Fang , Zhang Shao Guang , An Hai Qing
Published: June 2014

The linear regression method which will be influenced by fluctuations could only calculate constant background harmonic voltage. To make up the limitation, this paper studies partial linear method. The method expands fluctuant background harmonic voltage at a time in accordance with Taylor series. On the basis of least sum of square error, the objective function selected by the method considers the influence of weight and uses bandwidth control each size of weight. This method can calculate fluctuant background harmonic voltage accurately. A case study based on the IEEE 14-bus test system is conducted and the results indicate that fluctuant background harmonic voltage can be obtained effectively and accurately by the proposed method.
Simulation on Current Efficiency of Electrolytic Cleaning for Cold Rolled Strip
Authors: Liu Xiao Kui , Li Shuai Fang , Gao Peng Fei , Qiao Nan
Published: June 2014

The model of electrolytic cleaning for cold rolled strip was established, and the simulation of cleaning process was carried out in the finite element method with the software (Ansoft). The influence of processing parameters was investigated. The results show that, the processing parameters, such as the current efficiency, the electrode plate intervals and the insulation board have intense influence on current efficiency, which is significant for improving cleaning efficiency and energy conservation.
Simulation Study on Core Material of Weak DC Current Sensor
Authors: Meng Peng Fei , Wan Min , Yang Han , Ge Run Zhou
Published: June 2014

ZnMn ferrite, cold-rolled silicon steel, permalloy and nanocrystalline alloy can be used as magnetic cores of current sensors. And based on these four materials’ inherent characters of electromagnetic, this paper presents closed loop simulation model of them using Ansoft which is a finite element analysis software. In simulation, the measuring currents are set to DC currents ranging from 0 to 1mA. And different amplitudes of variation of currents are set for each material. The simulation of each material produces 280 sets of data and with these data a series of curves of magnetic field changing with currents can be plotted using Matlab. The simulation results show that permalloy and nanocrystalline alloy have good characters of electromagnetic and they are suitable for detecting weak DC currents. When these two materials are used as magnetic cores of sensors, the theoretical detecting accuracy can be up to 0.001mA, meanwhile, detecting accuracy of ZnMn ferrite is about 0.1mA to 0.01 mA.
The Design of Intelligent Pressure Detection and Alarm System
Authors: Fan Yu , Wu Xue Feng
Published: June 2014

An application of intelligent pressure detection and alarm system are studied in this paper . it is consists of the high integration, powerful function new microprocessor control, the internal integration of a large number of analog and digital peripheral module. The system has strong data processing ability. multifunctional intelligent hardware is not only realized in circuit necessary configuration,but also is a small size device. it ensure the intelligence function,and has the advantages of small volume, low cost, integration and strong anti-interference ability .
PIC/MCC Simulation of Glow Discharge in N2
Authors: Cheng Fang , Gao Ai Hua
Published: June 2014

The simulation of glow discharge in N2 in a needle-plane configuration with PIC/MCC method is presented. In the discharge channel the electric field driven by space charges is solved by PIC method, and various collisions between particles are described with MCC method. The electric field intensity, the electric potential and the net charge distribution in the discharge area are obtained. The numerical results are consistent with the corresponding features of glow discharge. This work can provide references to further study of glow discharge.
Fuzzy Comprehensive Assessment of Smart Grid Maturity
Authors: Wang Ming Dong , Su Wen Xia , Kong Bin
Published: June 2014

Smart grid must be evaluated correctly so that its development stage is determined and weak links, restrict factors in development are found. Based on it, the path from the stage to the next stage is planned for power enterprises. In view of the poor accuracy of conventional assessment methods, caused by subjective factors and uncertainty, the fuzzy comprehensive assessment method is applied to assess smart grid. Firstly, a smart grid assessment system is founded based of IBM’s smart grid maturity model, and then method and procedure of fuzzy comprehensive assessment method are introduced. The study on an example shows that this approach is effective and feasible.
Smart Metering for Applications
Authors: Pan Ying , Jiang Bo
Published: June 2014

As an important part of Smart Grid, smart metering attracts more and more attention all over the world. It is the way for energy consumer to sense the benefit of smart grid directly. Smart meter is an advanced energy meter that measures consumption of electrical energy providing additional information compared to a conventional energy meter. This paper discusses various applications and technologies that can be integrated with a smart meter. Smart meters can be used not only from the supply side monitoring but also for the demand side management as well. It plays an important role to monitor the performance and the energy usage of the grid loadings and power quality. In addition, This paper gives a comprehensive view on the benefit of smart metering in power network such as energy efficiency improvement.
Application Credibility Theory in the Smart Grid Information Network Security Assessment
Authors: Li Yan Bin , Li Yun , Li Wei Guo
Published: June 2014

With the development of the smart grid , information network securityassessment affects the safe operation of the smart grid . In this paper, theimproved credibility theory and analytic hierarchy process , combined withstructural features of the smart grid network , From the wide area network ,access network, enterprise local network , local area network and the CPN-siteand home users to assess the impact of the five aspects of information networksfor smart grid security operation. And make the case for more security strategyto improve the reliability of the smart grid operation , thus providing a basisfor guiding the development and safe use of electricity grid users .
The Analysis of Induced Voltage from AC Submarine Cable to Adjacent Communication Cable
Authors: Wang Yang , Zhang Guang Zhou , Chen Guo Zhi , Zhang Xiao Qin , Zheng Xin Long , Zhang Jian
Published: June 2014

The induced voltage generated by AC submarine cables would effect the normal operation of communication cables nearby. The paper calculated the induced voltage generated by AC submarine cable according to formula and procedures related to magnetic induction. The maximum parallel length between submarine cable and communications table was calculated under horizontal arrangement, and shielding effect was taken into account to the impact of the results. The causes of various induced voltage on communication cable were analysed under normal operation and various fault conditions. The results show that the induced voltage on communication cable is proportional to the parallel length and inversely proportional to parallel spacing. When the parallel length does not exceed a certain value, the induced voltage is in the allowable range and will not affect the normal operation of the communication cable.
FEM Simulations of Permanent-Magnet-Biased Saturation Based Fault Current Limiter
Authors: Song Shou Xiang , Zou Liang , Zhao Tong , Zhang Li , Li Qing Quan , Liu Meng Qi
Published: June 2014

The fault current limit technology based on the principle of permanent-magnet-biased saturation has several outstanding advantages in both economy and technology. A modeling method of PMFCL based on the finite element analysis platform – Maxwell is presented in this paper. The current limiting mechanism of line-type PMFCL is analyzed, on the basis of which the 2D and 3D models are established in Maxwell, and the corresponding experiments are designed as well. Comparisons between the simulation and experimental results indicate that the modeling method is reasonable. Research achievements of this paper provides theoretical basis for further studies of PMFCL.
Analysis and Prevention of Grid Over-Voltage Ferromagnetic Resonance
Authors: Lv Ming Jun , Zhao Xin , Zhao Xiang Dong , Liu Jian Guo , Liu Feng Zhen , Sun Yan Hui
Published: June 2014

Over-voltage in the power system can be caused by a lot of reasons , including higher frequency ferromagnetic resonance overvoltage which occurs in normal operation and causes great harm. Overvoltage events often result in damages to electrical equipment or even power outages . In this paper,ferromagnetic resonance is analyzed to study harm , causes, conditions , and phenomena and to handle resonance and develop practical preventive measures. The related analysis is important to work for the future operation of the power grid to prevent and limit the ferromagnetic resonance over voltage which provides some help to further ensure the safety and stable operation of the power grid .
A Electronic Control Stirling Engine Fuel Supply System Based on Real-Time Operating System
Authors: Liu Jian Xin , Chen Dong Wei , Wang Zhan Cheng , Xu Bin
Published: June 2014

The uC_OS-II embedded real-time operation system is used to improve the original designed fuel supply system of a Stirling engine which governed by the electronic control system based on a rotating speed control method. Task modules for each level are built and the fail-safe modules are also improved in this paper. The developed fuel supply system is investigated through experiment, and test results show that the new real-time operating system works stably and realizes the fuel supply fast adjustment.
Simulation of Transformer Protection Based on an Embedded MATLAB Function
Authors: Cai Wei , Sun Lin , Wu Hua Ren
Published: June 2014

This paper establishes a simulation model of a simplified power system with transformer differential protection based on an embedded Matlab function block. The differential protection consists of percentage restraint differential protection, second harmonic restraint, differential current instantaneous trip protection and over-excitation protection. The model is able to correctly simulate the transformer’s inrush current and internal and external faults. The results from the simulation show that the circuit breaker correctly operates for a transformer internal fault and provides a good braking effect for an external fault. In addition, the protection model is able to identify the inrush current of the transformer and avoid a protection mis-trip event.
Experimental Study on Variation of Gas and Heating Capacity about a Combustible Organic Rock
Authors: Ma Xiao Feng
Published: June 2014

the paper determines and calculates variation of gas and heating capacity in a combustible organic rock, the experiment shows that organic sample radiating intensity is low when temperature is below 110 °C, it gradually increased more than 110 °C when the heat release rate increases considerably. the speed of CO and CO2production rates increased slowly nevertheless the temperature is up to 65°C and raised faster and finally enhanced dramatically. Organic rock combustion can be inhibited effectively by lowering the temperature and reduce Organic Rock oxidation velocity.
The Mine Pressure Management and Control Fully-Mechanized Coal Working Face Roof and Floor of Soft Strata
Authors: Liu Ru Bin , Zhang Hai Yun
Published: June 2014

The “three volume” and the characteristics of deformation and damage of coal seam were observed and analyzed, the appropriate mine pressure control measures were proposed and put into production practice.
The Application of Crossing and Grid Drainage Boreholes in Floor Tunnel for Coal Roadway Safety Tunneling
Authors: Zhu Hong Qing , Gu Bei Fang , Zhang Min Bo , Yu Chao , Zhang Zhen
Published: June 2014

In order to reduce the danger of single coal seams outburst during the tunneling in coal roadway and ensure the tunneling of coal seams, this text analyzed the mechanism of crossing drilling against outburst; studied the area measures of floor tunnel crossing and grid drainage boreholes in coal roadway, Designed and optimized the drilling technical parameters; Analyzed the relationship between the drainage concentration and scalar; Calculated the maximum overlying coal seam gas to spare scalar quantity is 224300 m3 ;Used a variety of indicators to investigate the effect of outburst prevention. It shows that Gas content and gas pressure have significant lower than drainage. After the drainage up to standard, all the sensitive indexes is not overrun, during the coal roadway tunneling, it does not appears dynamic phenomenon. Solve the problem of mining imbalances, guaranteed the safety driving of roadway.
Discovery of Bioclastic Dolostone in the Second Member of Shahejie Formation in Bozhong Depression
Authors: Wang Yu Jing , Wang Jiao
Published: June 2014

Reservoir quality is the key for the petroleum exploration for middle-deep formation in the Bozhong Depression because the middle-deep reservoir is with the characteristics of big burial depth and poor physical property which is difficult to predict, but the physical property of dolostone reservoir (includes bioclastic dolostone and terrigenous clastic dolostone) is significant better than that of the clastic reservoir in the same depth in the second member of Shahejie Formation of QHD36-3 oil field, which could be one of the frontier for high production reservoir exploration. The paper concludes that the development of dolostone is mainly controlled by paleogeomorphology and paleo water depth as well as the distance from the source area. Building up the related sedimentary pattern is good for the exploration aiming at bioclasti dolostone and terrigenous clastic dolostone reservoir.
The Numerical Simulation of Overburden Strata Failure Law by Full-Mechanized Caving Mining in Extra Thick Coal Seams
Authors: Feng Shao Jie , Zhao Xue Fang , Sun Shi Guo
Published: June 2014

Given the irrationality and limitations in thick coal seam of the empirical formula of height of water flowing fractured zone , this article reveals the special thick seam fully mechanized mining damaging rules of overlying rock and determines the height of water flowing fractured zone with 3D finite element numerical simulation,according to the complex geological conditions and the special thick seam fully mechanized mining methods of Laohutai ore mining working face E5400 as an example. Results show that the destruction of repeated mining area of the overlying rock will have superposition effect and the superposition effect will increase with the development of mining; the fracture sharp of water fracture zones is in close proximity to the "arch". Simulation results and the actual detection height fitting is better, so it assesses the range of overburden water flowing fracture zones and rationality of the height.