bluuebunny/crossref_metadata_2025 huggingface dataset:
Study on Water Increment by Storm Tide in the East China Sea
Authors: Chen Ke Feng
Published: December 2014

Summary analysis of the East China Sea storm surge type, the East China Sea storm surge of factors, the calculation model typhoon pressure field were analyzed. Finally, the influence of the East China Sea eight kinds of selected typical typhoon was simulated for different types under the influence of the East China Sea typhoon storm surge were compared.
Study of the Quantitative Assessment of Rational Buoys Layout
Authors: Chai Tian
Published: December 2014

In order to evaluate rational buoys layout of the route quantitatively, the method of fuzzy comprehensive evaluation is applied to establish a rational buoys layout evaluation model. According to the 9 main factors that affect rational buoys layout, a quantitative assessment model is established. The AHP is used to determine weighted coefficients of assessment index. In the paper, the assessment for the buoys layout of three routes is carried out.
Approach and Realization of Energy Saving Technology Innovating at the Pump Station
Authors: Wang Zhao Han , Xuan Chang Guo
Published: December 2014

Rapid increase of energy consumption greatly restrains China’s sustainable development. Pump station is one of the high consumption systems in national economy. However, issues in design and management like low availability of equipment, unreasonable selection of water pump and no reactive power consumption capacitor lead to waste of energy and low efficiency of pump station, which shall be resolved during innovation of energy saving technology. Beginning with the current status of the pump station and through analyzing current problems, technology improvement measures are put forward in this paper such as expansion of irrigation area and performance adjustment of water pump. The sample evaluation is treated in a normalized way to get the optimal policy for energy saving technology innovation solution and achieve better economic benefits.
Effect of Accelerating on Sediment Incipient Motion over Dunes under Shallow Water Condition
Authors: Ma Dian Guang , Dong Wei Liang , Xu Jun Feng
Published: December 2014

Due to the complexity of bed form morphology and dune movement, this paper selected a series of 2-D asymmetric dunes in order to address the development of a flow region associated with velocity profile characteristics and sediment incipient motion under shallow water condition. Experiments were conducted over four asymmetric dunes of one crest length (4 m), two crest height (0.3m,0.4m) and two uniform sediments with mean grain sizes D=0.5 and 0.7 mm at the TianJin Research Institute For Water Transport Engineering, China. By using Acoustic Doppler Velocimeter (ADV), the instantaneous velocities were measured at four cross sections giving a total of 16 measured profiles. The variations of velocity profile along the flow affected by the wavy bottom have been studied. The results show that the effect of flow acceleration plays an important role in governing incipient motion over dunes.
Models of Subsidence Sinkhole in Soils around Reservoirs
Authors: Jiang Fu Wei , Lei Ming Tang , Dai Jian Ling , Jia Long , Wu Yuan Bin , Luo Wei Quan
Published: December 2014

The paper represents the models of subsidence sinkhole in soils around reservoirs in karst region. There are three essential conditions of the formation, such as cavity-fissure, overlying soils and groundwater dynamic. It leads to subsidence sinkhole based on three conditions when reservoirs change the underground hydrodynamics with regulating water. With the change of the surface water level controlled by reservoirs, the groundwater level alters, meaning to break the initial balance of sinkhole formation mechanism. Five models are established to describe the general mechanism change of groundwater hydrodynamic in this paper.
Seismic Analyses of 3D Fengman Concrete Gravity Dam
Authors: Wang Zhi Bin , Ma Feng Hai , Zhou Zhi Yu
Published: December 2014

In this paper, the new Fengman gravity dam is numerically simulated to study the seismic response and safety evaluation by considering the different strength grade concrete partition, corridor, a discharge hole and gate pier. A complex 3D FEM of a real overflow monolith was built by taking advantage of AutoCADand ANSYS, nonlinear seismic response was studied under earthquake loads. Numerical simulations show that acceleration, displacement and stresses of dam were obtained in a complex 3D FEM under seismic precautionary intensity of 7 degree earthquake loads, results compared with the dam simple models were on the safe side. Fengman dam was still safe under seismic precautionary intensity of 8 degree earthquake loads, so the dam had enough capacity to resist earthquake action. At the same time, it is concluded that 3D dynamic FEM is very important for safety evaluation of concrete gravity dam subjected to the earthquake. The research provides finite element analysis reference works for comprehensive governance and reconstruction of Fengman Hydropower Station.
Numerical Study on Hydrodynamic Environment Effect of Channel-Narrowing Project in the Complex Tidal Estuary
Authors: Song Ze Kun , Xu Xue Feng
Published: December 2014

The recent evolution of the North Branch of Changjiang Estuary is seriously affect the development of social economy in the region of Changjiang Estuary, regulation project of North Branch is extremely urgent. Now, the Channel-narrowing project in local implementation of North branch is already implemented. For study the effect of Channel-narrowing project on the hydrodynamic environment of the North Branch, a 2-D vertical average tidal current numerical model of Yangtze Estuary was set up with flexible irregular triangular grid to simulate the hydrodynamic before and after the Channel-narrowing Project in the North Branch. The following conclusions are drawn from the study. The results show that, the characteristics of tidal current in North Branches are not change a lot; the flood volume has been greatly decreased by the width of the North branch in the estuary area being narrowed down; the high tidal level lowers after the project. On the other hand, the low water level became increase and decrease, but the change of relative amplitude is not obvious. To sum up, the narrow project works to the advantage of the hydrodynamic environment in North branch.
Optimization of Seepage Prevention of Ma Erdang Hydropower Station
Authors: Qiu Li Ting , Shen Zhen Zhong , Tao Xiao Hu
Published: December 2014

Base on the design of seepage control, the three-dimensional non-steady saturated - unsaturated seepage finite element analysis program CNPM3D is used to establish the three-dimentional finite element seepage model of junction area during operating period. The seepage field of dam site area is studied under the different anti-seepage curtain arrangement scheme. Specifically, the seepage gradient and the seepage discharge of the panel, major material zone, foundation curtains and two sides abutment curtains are analyzed to evaluate the stability of the major district of dam area, in order to provide suggestions for choosing the seepage control standard in the next deepen design stage.The calculation results show that the panel and the impervious curtain anti-seepage effect is remarkable.Impervious curtain can greatly reduce the total seepage flow of the dam and its foundation.However the curtain deepened to 1Lu has little effect on seepage discharge. It is showed that the seepage prevention standards of 3 lu should be proposed in the deepen design stage for both security and economic benefit. The achievement and experience of this seepage prevention design should be taken into consideration for other similar projects.
Research on Problems and Countermeasures for Urbanization of Reservoir Resettlement in Guizhou Province
Authors: Wang Hai Bao
Published: December 2014

The reservoir filling arising out of the water conservancy and hydropower engineering development inundated a lot of fertile farmlands and good soils. Especially it was mountainous with scarce land in the southwest area, and the contradiction between man and land was prominent. The soil-based resettlement mode only possessed the textual meaning, rather than the practical operational meaning. It is necessary to adopt the urbanization and industrialization resettlement, so as to enable the resettlement to move out as well as dwell securely and become rich step by step. Through the field research, this paper summarizes the type during the urbanization process of reservoir resettlement in Guizhou Province at the present stage, discovers the existing difficulties and problems in the resettlement, and puts forward the relevant countermeasures and suggestions.
Study on the Influence of Tailrace Tunnel Outlet Bottom Slope on Water Level Fluctuation in the Tailrace Surge Tank
Authors: Zhang Zong Pu , Cai Fu Lin , Hua Yu Long , Cheng Huan
Published: December 2014

Combining with hydraulic model experiment of water diversion and power generation system of one hydropower station, the effects of different connection patterns between the tailrace tunnel outlet and downstream river bed and flow states in the transient process on the water level fluctuation in tailrace surge tank have been investigated. The results show that: there is not remarkable influence on water level fluctuation when tailrace water level in downstream river is higher or close to the ceiling height. On the opposite side , it has notable influence on water level fluctuation in the tailrace surge tank when tailrace water level in downstream is lower than the ceiling height, and the water level fluctuation in tailrace surge tank presents some regularity under the same connection pattern when the tailrace water level in downstream river is lower than the ceiling height.
Three-Dimensional Dynamic Visual Simulation of Slope Instability of Barrier Landslide
Authors: Tong Da Wei
Published: December 2014

The sliding movement of barrier landslide is a complex and dynamic process, because of the great effect of seismic action and huge surge. Adopting NURBS-TIN-BRep hybrid data structure and integrating with multi-source geological data, 3D geological model of the Tangjiashan quake dam was rebuild. The instability mechanism of the landslide was analyzed. Applying visualization technology, the whole formation process of the barrier dam, the production and development process of surge were fully and realistically displayed. These results above can help the engineering personnel to understand the whole condition of the Tangjiashan barrier dam. These research can provide some technical support for comprehensive governance scheme.
Upstream Slope Ratio Effects on the Heel Stress of Concrete Gravity Dam
Authors: Li Fen Hua , Xu Fang Xing , Lu Dong Hai
Published: December 2014

Heel is a critical area due to the high-gradient when the stress of a concrete gravity dam is analyzed. This article employed ANSYS, a kind of structure analysis software, to establish a two-dimensional model and to analyze the stress of a concrete gravity dam with Finite Element Method. Then the effects of upstream slope ratio on the stress of the dam heel in the operating conditions were researched and some valuable conclusions drawn from this paper can be adopted by the designer of concrete gravity dam.
Red Sandstone Aggregate Mixture Experimental Study of Dynamic Compaction High Fill Embankment
Authors: Chen Zhao Jun , Li Wen , Qu Xiang
Published: December 2014

Direct shear tests by laboratory to study the red sandstone aggregate mixture under the action of water intensity decay law, got red sandstone aggregate mixture, fill high subgrade compaction experimental study, tests showed that dynamic compaction compacted earth and rock mix fill embankment feasible, Rayleigh Wave test results show that the effect of dynamic compaction compaction good.
Study on Performance about Hybrid Fiber Concrete of Airport Pavement
Authors: Liu Xiao Jun , Zhu Che Fei , Wu Yong Gen , Liu Qing Tao
Published: December 2014

In order to meet the requirements of the use of aircraft, improve mechanical properties of pavement concrete, the steel fiber mixed basalt hybrid fiber reinforced concrete technical route was proposed, by using the method of orthogonal experiment, steel fiber with 1.2%,1.5%,1.8% these 3 volume fraction and basalt fiber in 0.05%,0.1%,0.15% these 3 volume fraction mixed, research the rules of its effect on the performance of airport pavement concrete.
Study on Highway Alignment Conformance Verification in Plain Terrain
Authors: Sha Sha , Hou Yu Ying
Published: December 2014

This paper mainly studies the index system and application method of highway alignment design conformance verification. Based on the actual conditions of vehicle running on the plane curve, straight section and curved slope combination section, the speed verification model formula is proposed. The results can be referred by the engineering and technical personnel in the design of highway engineering proposal in plain terrain.
Test and Numerical Simulation Study on Ice-Breaking of a Rubber Crumbs Asphalt Pavement
Authors: Zhang Hong Wei , Chang Ming Feng , Xie Chun Lei , Liu Zhen Zheng
Published: December 2014

A laboratory ice-breaking test was employed for an asphalt pavement with different dosage of rubber crumbs to study the ice-breaking effects by a self-developed road ice-breaking simulating tester. The mesoscopic model of rubber crumbs asphalt pavement structure with 2mm ice layer was established using the discrete element method, and the mesoscopic responses of rubber crumbs asphalt pavement structure were simulated under the standard axle loading. The results indicate that the weighted average rebound amounts of BPN with 3% rubber crumbs increase by 11.45% and 1.46%, respectively, compared with that of 2% and 4% rubber crumbs. The weighted average rebound rates of BPN with 3% rubber crumbs increase by 11.22% and 3.06%, respectively, compared with that of 2% and 4% rubber crumbs. For 3% rubber crumbs, the maximum contact forces in this pavement structure are the biggest which are 2.705×103N before loading and 2.706×103N after loading, and its strain energy is 1.34 times that of 2% rubber crumbs, 1.25 times that of 4% rubber crumbs. In addition, the results of numerical simulation are consistent with the results laboratory test.
Performance Evaluation of Warm Recycled SBS Modified Asphalt Mixture
Authors: Tian Rui , Xu Shi Fa , Suo Zhi , Yuan Guang You
Published: December 2014

The reclaimed asphalt pavement (RAP) materials with aged SBS bitumen were limited to applied in unmodified asphalt mixture for low level pavement structure by conventional recycling technology. To overcome this, a new recycling procedure was developed to recover the aged SBS RAP as modified asphalt mixture by warm mixing technology. The Marshall method was applied to design Warm Recycled SBS modified Asphalt Mixture (WRMA) with different RAP content (0, 20%, 30%, 40% and 50%). the performance properties of WRMA and hot recycled SBS modified asphalt mixture (HRMA), such as the high temperature stability, water stability and low temperature performance, were evaluated by the rutting test, low-temperature creep test, beam bending test and water immersion Marshall test, respectively. From the testing results, the properties of WRMA was more than HRMA significantly, and the warm recycling technology could effectively increase the RAP content applied in recycled pavement materials.
Research on Frost Heaving of Subgrade Filling in Seasonal Frozen Soil Area
Authors: Hou Jin Fang , Zhang Rui Qi , Yu Jian
Published: December 2014

Research on frost heaving of high speed railway subgrade filling in seasonal frozen soil area is developed indoor. Through freezing and thawing strength and frost heaving amount test, the research analyzes factors affecting frost heaving of subgrade filling, points out that water content, fine stuff admixing amount and plasticity of fine-grained soil have relatively large influence on frost heaving, while freezing temperature and freezing and thawing cycle index have relatively small influence. Water content is main factor to have effect on frost heaving of subgrade filling. When the water content reaches to some certain value, even coarse-grained soil can produce considerable frost heaving amount. Therefore, taking effective waterproof and drainage measures is of great importance in subgrade frost heaving prevention and treatment.
Setting of Function Layer of Cement Concrete Pavement
Authors: Hu Miao , Zheng Mu Lian , He Rui
Published: December 2014

The paper seeks to analyze the necessity of setting functional layer between base and surface course of cement concrete pavement. Based on laboratory test, test device is developed to test accumulated deformation of the functional layer mixture. Use common mixture AC-16, AC-13, and AC-10 to analyze the increasing law of cumulative deformation of mixture. According to the results, 3.5mm is set as the maximum limits of accumulated deformation for function layer under specified test condition in this article, which provides theoretical reference for the pavement layer design of cement concretes.
The Effect of Moisture Content on the Loess Physical Properties
Authors: Ma Lin
Published: December 2014

Water is one of the most important factors affecting the mechanical properties of soil.Research on the intrinsic mechanism of soil by water effect is significant. In this paper, the mechanical properties of loess in Shanxi under different water content is studied from the experimental angle. The result shows that the stress of intact loess increases with the water content decreasing. Pressure failure stress increases with water content decreasing under the same confining, and amplitude reduction increases.Keywords: moisture content; physical properties; intact soil; confining pressure
The Impact of Fine Aggregate on the Porosity of Asphalt
Authors: Sun Si Zhong
Published: December 2014

With different fine aggregate, gradation type, oil stone ratio, asphalt type specimen molding and molding method and calculate the porosity of the specimen. The experimental results show that the using basalt coarse aggregate and fine aggregate forming specimen, specimen porosity significantly larger, all are beyond the scope of regulatory requirements; If using basalt coarse aggregate and limestone fine aggregate forming specimens, specimen porosity is small, both meet regulatory requirements. The main reason is basalt fines aggregate bulk volume density is too large and not easily compacted. Recommendation: we’d better use of basalt coarse aggregate and limestone fine aggregate forming specimen, try to avoid using basalt aggregate thickness of molded specimen. If the region lacks limestone fines, we should detect the special type of basalt fine aggregate firstly. If the indicators of basalt fines are in line with the requirement, you can use, if the indicators do not meet regulatory requirement, you can not use.
Study on Surface Pressure Distribution Test of Stayed-Cable Using Aerodynamic Measure
Authors: Gong Sai , Tang Peng , Wang Cheng Kun
Published: December 2014

Stayed-cable was being considered as an important component of cable-stayed bridge, with characteristics of its low quality, stiffness and damping, among which rain-wind-induced vibration brings the most serious damage in its high amplitude because of its easy conditions to meet. This paper based on the theory of stayed-cable rain-wind-induced vibration, Through comparing different aerodynamic control measures in wind pressure test of ZhiJiang Bridge cable, this paper analyses the variation rules of two and three dimensional cable surface pressure distribution in different aerodynamic measures and cable aerodynamic coefficient in different surface conditions. The results show that: the wind angle influenced surface wind pressure coefficients and aerodynamic coefficient larger, especially between 25 ° and40 °; when the water was between 40 ° and70 °, the aerodynamic coefficient changed obviously, may happen galloping; It recommend that the cable helix parameter K1 was larger and K2 was between 0.01 and 0.03.
Prefabrication and Erection Technology of Wide Box Girders in Cross-Sea Bridge
Authors: Huang Yue , Wu Xing Fa
Published: December 2014

In the approach spans of Quanzhou Bay Cross-sea Bridge, these standard spans are 50m or 70m , width is 20.05m.The approach spans have been built by using short Line segments precast and erection method. This is the first application in the cross sea bridges. According to characteristics of this project, the research on prefabrication and erection technology of wide box girders has been carried out to solve the technical problems in the process of construction. The research show that: 1)In precasting process , the vertical deformation of wide box girder is very small under dead load and temperature load etc. so the influence of prefabrication and erection accuracy can be ignored; 2)The temporary anchor using prestressed steel strand better than planished steel; 3) When using epoxy gasket to adjust geometric line shape, the thickness of cemented layer has a great influence on the linear adjustment;4)The epoxy gasket and bridge erecting machine should be used together, Alignment adjustmen could obtain satisfactory results.
Reinforcement Design Research Study of a Double Curved Arch Bridge
Authors: Guo Bo
Published: December 2014

According to the status quo detection of Wang Tong Gang Bridge, with the research of the reinforcement schemes, a reinforcement scheme of the bridge is put forward, through which the increasing bearing capacity of the bridge was tested.
The Overture and Three Dimensions Numerical Simulation of the Pile Foundation of the Mountain Superhigh Bridge
Authors: Li Chun Peng , Xu Guang Li , Yu Feng , Zhao Yun , Zhu Lin Feng
Published: December 2014

It is very important for the deformation control of the bridge pile foundation in the design of bridge with high piers. Using the Three Dimensions Numerical Simulation, the stabilizing project about anchor reinforced pile foundation which is based on the geological characteristics of the 405 federal highways is simulated analyzed. According to the stimulant result, we can see that anchor reinforced pile foundation can control the dimensions effectively and reduce investment compared with the general pile foundation.
Research on Disease Analysis and Maintaining Technology of Bridges for Middle and Short Span in Nantong
Authors: Chen Ning , Ma Zhi Hua , Bai Ping , Liu Qiu Yang
Published: December 2014

Under the impact of environment, climate, conservation conditions and other factors, forms of bridge disease vary in different areas. This paper has researched on concrete bridges for middle and short span in Nantong. Through the investigation of bridges disease in Nantong and statistical analysis of the main structure type and related diseases, what can be seen is that the bridge diseases have a strong correlation with the region.Considering the characteristics in this area, by analyzing the common damage of bridges of different forms, the maintaining methods which are suitable for different forms have been put forward.
A Discussion of the Stability of Foundation Pit or Slope with Soft Interlayer or with Back Berm
Authors: Hu Hai Ying , Zhou Xiao Wen , Huang Zhi Xing
Published: December 2014

The soft soil in Pearl River Delta regions is characterized with high water content, high compressibility and low bearing capacity. Therefore, when building the structures on such foundation, it’s necessary to pay attention to the deformation and stability. The projects' practice shows that, when analyzing the stability on foundation pit or slope with soft interlayer, it should not only calculate the overall stability of the slope, but also calculate the stability or bearing capacity of the foundation. Although sometimes the stability of the slope meets the requirements, it doesn’t means that the bearing capacity of the foundation meets the requirements because of the existence soft interlayer, the limitations of the circle slice method and the difference between the sliding surface and the actual sliding surface.
Study on the most Reasonable Layers of Reinforcement for Stone Arch Bridge through Section Enlargement Method
Authors: Chen Jun Xia , Li Ming , Liu Xin , Tan Lin Li
Published: December 2014

In order to research the most reasonable layers of reinforcement for stone arch bridge through section enlargement method, based on a bridge, on the premise of ensuring coordinated consolidation layer and original structural deformation, the finite element software is adopted to analyze the stress state of old and new concrete with different thickness of reinforcement for arch ring with the detailed exploration and structure evaluation data. Through consolidate the optimal reinforcement layer, in order to maximize the whole bridge bearing capability, then each section mechanical performance is improved, achieving ideal reinforcement, the conclusion can be used to reference for similar reinforcement design and construction, reducing workload of trial and calculation to increase the cross section technology.
The Calculation of the Nan Poping Yellow River Bridge in Lanzhou-Chongqing Railway
Authors: He Wen She , Wu Lan Zhen , Zhao Su Min , Chang Kai
Published: December 2014

Based on introducing engineering background and characteristics of river, the Yellow River in lanzhou section of the hydrological and sediment characteristics and characteristics of riverbed evolution are analyzed. On this basis, determine the once-in-a-century flow, and calculate the once-in-a-century flow when the bridge was analyzed and local scour of general erosion depth, scope of backwater height, etc.On the bridge of the embedment depth, clearance under the bridge, such as the check, and the bridge construction impact on the stability of river regime is analyzed.
The Verification of Geometry Control Method for Cable-Stayed Bridge
Authors: Huang Can , Bu Yi Zhi , Zhang Qing Hua
Published: December 2014

Based on the energy method and beam-element theory, the nonlinear strain are considered, non-stress length and non-stress curvature of element of geometry control method are introducted in the integration process of stain energy. The static equilibrium equation of the geometry control method is established. Take the impacts of structural geometric profile induced by temporary loads and temperature field during the construction procedure are investigated, the correctness of the geometry control method is verified by the numerical simulation analysis.
Analysis on Lightning Withstand Level of Back Striking Flashover for Double-Circuit Transmission Line
Authors: Xie Shi Jun , Li Jian Ming , Jiang Yu Han , Zhang Yu
Published: December 2014

The double-circuit transmission lines have already been the significant component of power system. Because of the symmetric insulation of the two circuits, the case that both circuits trip out often happens when the tower suffer lightning strike. And it harms the stability of power system and causes serious impacts to power equipments. In this paper, an electric-magnetic transient simulation model was established. Using this model, combining the analysis of physical mechanism of back striking trip-out, the influences of earth resistance, height of tower and length of insulator on the lightning withstand level of back striking (LWLBS) were clarified. The LWLBS of high tower is much low, therefore the relative high tower should be paid more attention to defense the back striking. Reducing the earth resistance and increasing the length of insulator can both upgrade the LWLBS observably. Especially, reducing the earth resistance can enhance the effect of upgrading the LWLBS by increasing the length of insulator.
Study on Movable Equipment for Realizing Seamless On-Shore Seamless Power Supply for Berthing Vessels
Authors: Xiao Le Ming , Song Yan Qiong , Li Jian
Published: December 2014

The dissertation demonstrated movable equipment to realize uninterruptable power supply on-shore connection, i.e. the movable switchgear and mobile synchronizing cabinet, which can unchanging structure of ship power station rather than hugely increase the investment of shore power transformation, and also achieve continuous electricity power supply for domestic vessels berthing on the ports with shore power interface connecting on-shore power, so as to realize environmental protection in port and expenditure savings for the ship. Ship controlling shore power connection system, by means of the movable switchgear and mobile synchronizing cabinet, can achieve paralleling operation between 400 V/ 50 Hz shore power and marine power generator correspondingly, and also transferring the load and paralleling off marine generators, as well as, paralleling accordingly marine generator with the shore power, corresponding transferring load and cut off shore power. Movable equipment for realizing seamless power supply between the port and ship is simple, reliable, convenient, economical and efficient. The dissertation proves that the device is simple, reliable, convenient, economical and efficient.
Comparison of Application of SVC and STATCOM on Suppressing Subsynchronous Oscillation
Authors: Chen Qin Lei , Guo Chun Lin
Published: December 2014

As the main types of parallel FACTS devices, the basic function of SVC and STATCOM is to realize the dynamic compensation of reactive power and maintain system voltage stability. However, when new control strategies are added to them .Both of them can suppress SSO effectively. Based on IEEE first benchmark model, this paper established simulation model by PSCAD/EMTDC. The effects of suppressing SSO by SVC/STATCOM are verified with time domain simulation, and the comparative analyses are carried out on the effects of suppressing SSO by SVC and STATCOM.
A New Method for Partial Discharge Signal Processing
Authors: Li Hui Qi , Wang Kai Hong
Published: December 2014

A partial discharge (PD) signal processing method based on dynamic measurement theory and wavelet transform is proposed in this paper. The deterministic component was separated by polynomial fitting, and the random component of the remaining residual after the separation was estimated using autoregressive (AR) model; The true value estimate and dynamic measurement uncertainty of noisy signal were obtained by the deterministic component and random component;Db8 wavelet and the soft threshold based on Stein’s Unbiased Estimate of Risk were used to smoothly denoise for better PD signal processing. Finally, the effectiveness of the method was verified by MATLAB simulation and experimental noisy PD signal extraction.
Influence of Corona Discharge on SAW Temperature Measurement System
Authors: Zou Liang , Zhang Xiu Qun , Zhao Xin Hua , Tian Chun , Duan Hui
Published: December 2014

In order to study the electromagnetic interference on SAW (surface acoustic wave) wireless temperature measurement system of the corona discharge, the paper analyzes the characteristics of the frequency spectrum of corona discharge, models the corona discharge and studies its radiation characteristics by simulation on Matlab. Based on this, the experimental platforms of corona discharge is set up. The result of the experiment confirms that corona discharge causes electromagnetic interference to the system and the influence decreases as the distance between the sensor and discharge sources increase. Then the sensor should be kept a certain distance from the discharge sources.
Software Design and Implementation of Measuring System of Transmission Lines Based on Wireless Communication
Authors: Cheng Yan , Sun Shu Min , Meng Yu , Wang Rui Qi , Dong Pan Ting
Published: December 2014

The software of measurement system for the transmission line debugging was designed. The transmission line is based on wireless communication. This software of measurement system is composed of acquisition controller software system and center station software system. The measurement system realized the function of data storage, waveform display, data analysis, automatic report generation and others. The field experiments were conducted at a 500kV substation in a Power Grid. The experiment proved the validity and reliability of the measurement system. The measurement system can avoid complex wiring work in substation debugging field, thus improve the experimental efficiency.
An Adaptive Speed Control Approach for Sensorless Brushless DC Motors
Authors: Cao Fu Cheng , Shi Ji Xia
Published: December 2014

This research presents a new adaptive speed controller for the brushless DC motor. Themethodology of model reference adaptive control is applied to a novel model of BLDC motor. Thisnovel model provides the possibility to compensate the torque ripples and load torque.
Sliding Mode Variable Structure Direct Instantaneous Power Control of Grid-Connected Converter with an LCL Filter
Authors: Luo Zhi Qun , Wang Yan Qing , Wan Jian Ru , Huang Shao Lun
Published: December 2014

Aim at solving the complex computation and complicated circuit of grid-connected converter, the sliding mode variable structure theory is introduced into its direct instantaneous power control. By analysis and modeling of three-phase grid-connected converter with an LCL-filter, sliding mode variable structure control is constructed with the active power and reactive power. The chattering is weakened by using the exponential reaching law. Cost of LCL grid-connected converter system is reduced at the same time when unit power factor and low harmonic distortion are realized. In order to increase the stability of the system, the virtual flux variable is integrated with the sliding-mode variable structure direct power control algorithm, and the improved first-order low pass filter virtual flux is used to remove the voltage sensor. By simulation, the effectiveness and feasibility of the control method is proved.
Research on Constant Frequency Electrical Angle Start Method of LCI
Authors: Ji Lian Tao , Wang De Shun , Yu Bin , Zhao Shang Lin , Kong Ai Liang , Zhang Xin Long , Han Gui Gang
Published: December 2014

Load-commutated inverters (LCIs) are the key starting device of wound-field synchronous motor. By detecting the rotor position and inputting a variable frequent current to the stator windings, the LCI can drive the motor from standstill to a given speed. Thus, rotor position detecting method comes to be the key techniques, but at the ultra-low speed period, the motor’s terminal voltage is too low to accurately sampling and is vulnerable to the interference, which brings risks to the variable frequency driving. In this paper, through analyzing the principles of LCIs and synchronous machine, a constant frequency electrical angle control methods is introduced to solve the difficulty of detecting the rotor position in the low speed period. A 98MW synchronous machine driven with an 18MW LCI are experimented in MATLAB and RTDS systems, the results show that the proposed control strategy can realize soft-start of the wound-field synchronous motor without detecting rotor’s position.
Optimization of PI Control Parameters for Shunt Active Power Filter Based on PSO
Authors: He Dong Chen , Wu Lin Zhang , Wu Tie Zhou , Jiang Xiao Wei
Published: December 2014

This paper presents a method based improved particle swarm optimization optimizing PI control parameters. When the load changes, parallel active power filter, in the traditional PI control strategies, can not well control DC voltage fluctuations leading the deterioration of its dynamic performance. This paper proposes the improved particle swarm algorithm by increasing symbolic function of inertia weight parameter in particle swarm algorithm, and changing position of the random number in the speed update equation. The improved particle swarm algorithm can avoid "premature" or fall into local optimal solution, so it could get a more accurate solution set. Using improved particle swarm algorithm to solve PI controller optimization objective function, to get a more accurate PI control parameters. Simulation and experimental results show that mutations in the case load, the overshooting of an capacitor DC voltage compare with the traditional PI control reduces 5.5%, compared with Particle Swarm Optimization reduces 1.5%. Based on the simulation analyses and experimental results, it has been proved that this method can realize a comprehensive optimization.
Simulation on Multi-Level Current Source SVG
Authors: Zhang Shu Yu , Yang Bao Feng , Zhang Hang , Wu Jing Kai
Published: December 2014

The operational principle and topology of multi-level current source converter as well as its main advantages are introduced. According to the characteristics of SVG (Static Var Generator), a model of multi-level current source SVG is built up and simulated with PSCAD/EMTDC. The influences of model parameters on the performance of SVG are discussed in the form of dynamic and steady waveforms of system voltage and current. Simulation results display the feasibility of proposed control strategy and the excellent performance of multi-level current source SVG.
Research on Dual-Mode Control Strategy of Energy Storage System in Microgrid
Authors: Li Guan Jun , Sang Bing Yu , Zhang Yu
Published: December 2014

As wind power, solar and other new energy development, new energy itself has intermittent, fluctuation characteristics, which bring great challenges to the safe and stable operation of power grid. This paper will construct semi real object simulation system research platform with the RTDS real-time simulation system, storage controller, power amplifiers and other equipment, focus on control strategy of energy storage system in a Micro Grid, mainly grid PQ control, off-grid V / F control and two conditions of each conversion control technology.
Comprehensive Evaluation Index System and Method of Smart Distribution Grid
Authors: Chen Hong , Yang Chun Ming , Yang Jun Xia , Lu Zhen , Lu Zhi Ying , Liu Hong , Wang Shi Ju , Chen Jing
Published: December 2014

The core value of smart grid lies in the satisfaction extent of stakeholder’s demand, thus to construct an evaluation index system for smart grid it is necessary to construct a stakeholder’s demand index set at first to access the satisfaction extent of stakeholder’s demand reasonably and roundly. We divide the index system into the demand index set and assessment index set. As the former represents the macroscopic features while the latter represents the microscopic factors of the smart distribution grid. As for the calculation of combination weight, the DEMATEL-ANP-anti-entropy weight method and the improved Grey incidence approach is proposed. The DEMATEL-ANP-anti-entropy weight method is used for demand indices’ weight analysis, while the improved Grey incidence approach is put forward for the evaluation on assessment indices. Results of applying the proposed method in practical case shows that the proposed method is valuable in following aspects: scientifically assessing the intelligent development level and effectiveness of distribution grid, analyzing and recognizing the grid’s operation condition and weak link, giving reference to planning and construction of smart distribution grid, and so on.
The Research and Application on Design Method for “Virtual Terminal” of Smart Substation
Authors: Ren Hao , Du Qi Wei , Dou Ren Hui , Yao Zhi Qiang
Published: December 2014

According to the new changes brought out by the smart substation, including disappearance of the traditional concept of terminal and replacement of the original point to point cable connection by optical fiber network, a new design method of GOOSE “virtual terminal” is put forward. The method contains GOOSE “virtual terminal”, virtual terminal logic connection line, GOOSE configuration table and virtual terminal information flow diagram, and solves some problems of digital protection, measurement and control device, such as without contact, no terminal, no wiring etc. of GOOSE information. The design method was applied in the engineering practice of the south of Changshu 500kV smart substation in Suzhou, and the effect of designing was very good.
A New Method of Power System Load Forecasting Based on Intelligent Optimization Algorithm
Authors: Cong Zhong Xiao , Li Peng Cheng , Ou Jia Xiang , Peng Zhi Wei
Published: December 2014

Based on the research on the basis of analyzing the mechanism of polynomial fitting model, The polynomial fitting model or method was established based on intelligent optimization algorithm. The proposed method was applied to electric power system load forecasting, by a practical example’s calculation and analysis, this proposed intelligent optimization algorithm or method was verified to be feasible in the power system load forecasting, the results also showed that the method was compared with the traditional algorithm has superiority and has a broad application prospect in the field of polynomial fitting.
A Study on Factors and Causal Loop of Chinese Residential Electricity Price Policy
Authors: Chen Zhuo , Luo Bin , Huang Chen Yu
Published: December 2014

High electricity cost generated from the residents dispersion and the market failure resulted from the natural monopoly of the electricity supply industry make the traditional pricing theory which is based on the cost, market and competition suffer challenge in the decision of residential electricity price (REP). The paper analyzes the main factors influencing residential electricity price policy (REPP) to assist the relevant government decisions from perspectives of the residential affordability, the average electricity sales price, alternative energy and other policies. Furthermore, the conduction path of the factors influencing and deciding REPP is analyzed and a cause-effect diagram is produced with system dynamics software.
A Study on Key Factors and their Conduction Path of Chinese Rural Residential Electricity Price
Authors: Luo Bin , Zhang Yi Fei , Chen Zhuo
Published: December 2014

This paper reviews the existing Chinese rural residential electricity price policies, including their features and forming foundations, then analyses the main factors affecting the current Chinese rural residential electricity price by considering electricity generation, transmission and demands, respectively. With the gray relational analysis and the statistical data, the key factors currently affecting Chinese rural residential electricity price can be given as: the average of air conditioners per household, the average lending rates, rural residential per capita net incomes, natural gas price, price of coals for power generation, per capita electricity consumptions in daily life, total electricity consumption, total electricity production, electricity infrastructure investment and cross-subsidies in the electricity sector. Furthermore, the conduction path of the key factors influencing and deciding the electricity price is analyzed and a cause-effect diagram is produced with system dynamics software.
The Mechanism Design to Direct Power-Purchase Transaction Considering Market Supply and Demand
Authors: Zeng Wei Min , Liu Dun Nan , Liu Jiang Ping , Tang Tian Qi , Yang Xian Gui , Fan Min
Published: December 2014

At present, direct power-purchase for large consumers is difficult to carry out effectively when demand exceeds supply. Interest demand of direct power-purchase for large consumers under different conditions of supply and demand is analyzed in this paper. Therefore, design principle of transaction mechanism for direct transaction adapting to different supply and demand situation is also applied. The purpose is striving to carry out the direct transaction effectively when market demand exceeds supply situation, adjusting the supply and demand and solving the "soft lack of electricity" phenomenon due to fluctuation of coal price. In the end, some suggestions are put forward to the current transaction rules.
The Business Optimization Analysis of the Virtual Power Plant Based on the Large-Scale BESS System
Authors: Yan Tao , Qu Zhan Zhan , Hui Dong , Liu Yun Jia , Jia Peng Fei , Lai Xiao Kang
Published: December 2014

In the new energy power generation process, because it’s difficult to balance the dynamic energy and the system operation cost is high, the paper puts forward the basic structure of the commercial virtual power plant based on BESS system, then discuss the proper run mode of the virtual power plant to maximize the total revenue. On the basis of the electricity price of the Chinese typical areas and the cost of the BESS system, the paper builds the mathematical model of the economic benefits of the virtual power plant based on BESS system. This paper also builds the regulation optimization simulation model of the virtual power plant based on the aim of maximizing the overall profit of the energy supply and demand sides, and calculates the dynamic balance elements and optimization optimal power output value based on optimization algorithm. The simulation results show that using the virtual power plant based on BESS system to peak load shifting and control frequency is feasible in the economy.
Characteristic Analysis of the Electricity Price Fluctuation: An Empirical Analysis Based on California’s Day-Ahead Market
Authors: Xie Pin Jie , Huang Chen Chen , Pan Xian You
Published: December 2014

The paper deals with the Day-ahead Market of California between Apr. 1st, 1998 and Jan. 31, 2001 and divided each day to high-load period and low-load period, described the characteristics of electricity price fluctuation by ARCH models. The results showed that ARCH models under t-distribution matched the volatility of the sample series quite well, captured the series’ heteroscedasticity and the obvious peak and fat tail effectively; the total risk of the day-ahead market in the sample was high, the impacts from external information on the conditional variances was permanent and sustainable, the impacts could not disappear in a short time once the price were fluctuated; the daily mean price fluctuation and low-load period price fluctuation were not asymmetric; while high-load period were significantly asymmetrical.
Small-Signal Equivalent Circuit Modeling and Controller Design of DC/DC Converter Based on Matlab
Authors: Xiao Xiao Long , Lu Xiao Jun , Yi Jian Wei , Ding Xiao Hua
Published: December 2014

The model-building of DC/DC converter is the key to design the control of system. It is important to study DC/DC converter stability and dynamic performance. A small-signal model of buck/boost circuit was built by average state-space. By analyzing the transfer function of buck/boost circuit, a voltage closed-loop feedback system was designed. Building system of simulation circuit in the Matlab, the result of simulation shows the system has a good static and dynamic performance. It verifies the rationality of the mathematical model and control strategy. It verifies the rationality of the mathematical model and control strategy.
The Solar-GSHP System Applied in the Administrative Regiona of a TYPICAL Port
Authors: Zhang Jian , Zhai Jian Feng , Chen Jie
Published: December 2014

On the basis of analyzing the building status of a typical port, the energy consumption characteristics of the port buildings were studied. Solar energy-ground source heat pump system was used in the port buildings, the system runs stably. Good heating and cooling performance fully meet users’ requirements. It makes the port building energy conservation operate, it moves forward the port development direction of building energy conservation measures.