Global energy crisis and environmental pollution make clean,renewable energy to get attention,wind power as the development and utilization of wind energy in the attention of many countries in the world,and actively encourage wind power,wind power worldwide rapid growth and expansion,so that wind power Current Situation and Prospect considerable.Status of this article cumulative installed capacity of world wind power,single group capacity,the unit design and manufacturing and control technology and offshore wind power and other combed,analysis and induction,and China's wind power development and problems were described in detail;indicates wind power development trends and the development direction of China's wind power.To fully grasp the status of the world wind power generation;understanding of wind power development trends;guiding the development of China's wind power,look for gaps and accelerate the process of domestic wind power technology has important significance.

According to the economic problems of family pv power in different operation modes,the LCOE model of family PV power is constructed based on the classic leveling cost model.The model accurately measures the cost of the unit's electricity consumption in the operating period of family pv power station and can quantify the economic driving strength of each factor to the various operating modes,So as to find out the key factors that affect the economy of each operating modes.The paper calculates and analyzes the economy and characteristics of different operating modes by taking the family pv in a certain area,and then,the correctness and validity of the model are verified.

Wind Power Prediction is an important method to cope with problems when large scale wind power is integrated into grid.The basic method to predict wind power is introduced.The status of research and application of wind power prediction technology at home and abroad is also summarized briefly.At last,the development trend of wind power prediction is prospected.

Distributed photovoltaic power generation has received extensive attention in recent years,and the time variation of photovoltaic system is very important to evaluate its reliability.In this paper,the time variation of illumination is analyzed,and the power output model and the solar radiation probability density model are established.The multi state power output and its failure probability model are obtained by using the relationship between the two models and the traditional 2 state model.Based on the failure characteristics of the element,a multi state power output and its failure probability model considering the light fluctuation and component failure are established.The reliability evaluation of photovoltaic power generation system based on the convolution method combined with the load model.Finally,MATLAB programming is used to calculate the example to verify the rationality of the proposed model.The results show that the model is more accurate in evaluating the reliability of distributed photovoltaic power generation system.

In the city,building the tunnel will inevitably affect the ground buildings,so tunnel construction of surface displacement needing to be studied.Taking double orifice size tunnel as an example,vertical through the earth's surface,using Midas/GTS simulates the influence of both the foundation of the earth's surface caused by tunnel construction,analysing the construction settlement and consolidation settlement respectively.Results show that two tunnel construction settlement value is larger than the single tunnel construction at the same time,consolidation settlement is in a major proportion of the total settlement,tunnel construction settlement is larger than that of small tunnel,the maximum of total settlement appears during two tunnel border area.

The strengthening heat transfer principle of the wire coil equipment is summarized.The three-dimensional simulation of the plain tube and heat exchange tube with wire coil has been performed using the FLUENT software.The velocity,temperature and pressure distribution as well as thermal process is obtained.The results showed that the flow characteristics in the heat exchange tube with wire coil was more complex than that in the plain one and the fluid near the wall presented apparent spiral flow.Meanwhile,the radial and tangential velocity both increased obviously.In general,the turbulence intensity was strengthened in the heat exchange tube with wire coil.Moreover,the velocity boundary layer was broken,and the heat convection was enhanced.So,the heat coefficient was improved tremendously.

Algorithms of the state estimation are regarded as the core part of the state estimation.Firstly,the basic concepts and mathematical models of the power system state estimation are descripted briefly.Then the corrent proposed algorithms for power system state estimation,including:least square algorithm,fast decoupled method,orthogonal transformation algorithm,state estimation algorithm based on measurement transformation, district coordinated algorithm,etc.are surveyed.the advantages and disadvantages of each method are reviewed as well.Finally,the main development trends of state estimation are pointed out.

Active distribution network is the high-level technical stage that the intelligent electrical network develops.It is a distribution network,what can controls various distributional energy (distributional power source,stored energy,controllable load and demand side response).And it is an open system structure cores which can compatible other microgrid electrical networks and new energy integration technologies.Finally determined the way for microgrid fault ride-through.This article in this structure core foundation,through Photovoltaic power generation systems and Wind power generation system fault ride-through to study.At the same time,this article has carried on the modeling analysis for Microgrid fault ride-through of active distribution network.

With the increasing scale of the wind farm,wind power climbing events to the effects of the power grid is more and more significant.This paper expounds the definition of climbing event,a recognition method based on wavelet transform(WT) was proposed for wind power climbing event,a WT-SVM prediction model was established for wind power climbing event.The examples use wind power data of a wind farm,and the identification and prediction of the wind power are carried out at different times.The results show that,the method based on WT can quickly and accurately identify wind power climbing event and its characteristic value,the WT-SVM prediction model can improve the wind power climbing event prediction accuracy.

机械工程学院团队简介

The preparation and application of nanosized titanium dioxide is mainly introduced in this article. According to the different physical form of reaction system, its fabrication methods can be divided into gas phase method,the liquid phase method and solid phase method. Gas phase method includes chemical vapor deposition and physical vapor deposition,and liquid phase method can be classified into sol-gel method,hydrothermal method,liquid phase deposition method and micro-emulsion method, and solid phase method includes solid mix method and direct high-temperature calcination. And furthermore,titanium dioxide had the function of disinfection and sterilization when it was added in the plastic products.

The screw pile is a kind of new type pile with variable cross section and Special-shaped.The pile type has good environmental protection effect,reliable quality and high bearing capacity of pile,and the advantages of low construction cost,short construction period is widely used.This paper introduces the technology,working mechanism and the screw pile formation technology,screw the calculation method of ultimate bearing capacity of pile are analyzed,and proved that the calculation method on the engineering example has a certain guiding role.

Fiber Optical Current Transformers have broad application prospects in the power system because of its good insulation properties,high safety,wide dynamic range,high accuracy,digital output,etc.The performance of the traditional electromagnetic current transformer and Fiber Optical Current Transformer are compared in this paper.The Faraday magneto-optic effect principle of Fiber Optical Current Transformer and the typical structural models of All-Fiber-Optical Current Transformer are described.Additionally,the recent research advance of All-Fiber-Optical Current Transformer is reviewed,and its key problems and solutions that appeared in the research and practical procedure are summed up.

Numerical simulation for combustion in furnace,heat transfer and the flue gas flow on a 600MW supercritical tangential boiler was carried out by using the CFD method.Gas temperature and gas velocity distribution were obtained.Combined with the simulation results and the numerical calculation theory,we did the thermal deviation of the boiler superheater tube wall temperature for 3 dimensional computing research.Finally we've got the superheater tube wall temperature distribution,and found out the position where the tube wall temperature is highest.Based on the method,temperature can be easily and accurately acquired by computational program.

The hydrodynamics of the plasma jet are simulated,the relationship between the field strength and the electrode thickness and the distance between the electrodes is analyzed.The changes of the helium flow rate and the molar distribution in the axial and radial directions at different initial velocities are analyzed and discussed.The influence of the weakened field strength on the ionization rate coefficient,the excitation rate coefficient of He^* and the excitation rate coefficient of N₂(C³Π_u) are analyzed and discussed.The experimental results show that the maximum and minimum values of the field strength appear in the vicinity of the anode.In order to enhance the electric field near the anode,the thickness d of the electrode plates can be reduced to a certain extent and the distance D₂ between the two electrode plates can be reduced.In the axial direction,with the increase of z,the VHE gradually decays and the molar distribution of helium decreases gradually.In the radial direction,as the r increases,the VHE gradually decays and the molar distribution of helium decreases.With the decrease of the electric field,the ionization rate coefficient,the excitation rate coefficient of He^* and the excitation rate coefficient of N₂(C³Π_u) do not change much at first.When the electric field continues to decrease,the amplitude of the three coefficients decreases getting bigger and bigger,more and more obvious.

Compared with non-renewable energy (coal,oil,et al),renewable energy (solar,wind and so on) could not storage directly,and have to complete energy storage through energy transformation.Energy storage technology is the key technology to solve unsteady characteristics for generating electricity by renewable energy.It is one of the effective ways to breakthrough energy storage technology bottleneck through development of stable and efficient energy storage materials.Polyoxometalates have the strong ability of electron and proton transfer and storage,so the study of polyoxometalate-functionalized energy storage materials has raised more concerns in recent years.The paper is about the literature review of polyoxometalate-functionalized energy storage materials.

Noble metal doped TiO₂ photocatalyst can overcome many shortcomings of the star material pure TiO₂ in the photocatalytic application.In this paper,we explore the photocatalytic mechanism of pure TiO₂ and noble metal doped TiO₂ photocatalyst,by listing the specific examples of Pt,Ag,Au and other noble metal doped TiO₂ photocatalyst,the current research achievements and existing problems of noble metal doped TiO₂ photocatalyst were analyzed comprehensively,and the research of noble metal doped TiO₂ photocatalyst was prospected.

Double-circuit transmission line double-circuit flashover is a big accident,which is bad for the stability of the power system.There were two double-circuit transmission line double-circuit flashover hitting in a certain region,the paper use EMTP lightning flashover model to simulate.The results shows that when the lightning hit the top of the tower will cause the C-phase flashover,which is consistent with actual running situation.Through the comparison of the contribution of several components in lightning overvoltage to the final overvoltage on the insulator,we learn that power frequency voltage is the main reason affecting double-circuit transmission line flashover's order.Reducing the impulse grounding resistance and installing line lightning arrester is the most effective ways of improving the lightning resisting level and reduce lightning trip-out rate.According to the result analysis,if only one-phase line arresters are installed on 220kV double-circuit transmission line,they should be installed on middle-phases or bottom-phase;if two line surge arresters are installed on two phase on every circuit,they should be mounted on two middle and two bottom phases.

With the continuous development of flexible direct current transmission technology,and proliferating breakthroughs in the research of dc circuit breaker,the gradual application of dc circuit breaker will impact on the relay protection of MMC-HVDC system.In MMC-HVDC ac/dc hybrid system with dc circuit breaker,some faults will be cut changing from the dc side of the ac circuit breaker tripping for the action in the dc circuit breaker tripping.Under this background,the ac failure and dc failure reflected in the transient response of the dc side has the similarity,may cause dc protection misoperation.In this paper,we study all kinds of ac and dc system fault transient response of the dc system,to analysis the similarity between MMC-HVDC dc side in the ac system fault and dc system fault transient response,research the possibility to cause the dc voltage protection maloperation,and cause maloperation of the protection features avoid protection maloperation improvement suggestions are presented.Building MMC-HVDC ac/dc hybrid system in PSCAD/EMTDC simulation platform,the simulation verify the correctness of the analysis made.

In this paper,in connection with the actual situation of a large number of low temperature waste heat which is discharged with the recycled water in the steam turbine's production process at the three thermal power plant in Changchun.then we research some of the heat is recovered by the heat pump technology in 0r. der to achieve the winter heating program.The principle of the heat pump technology which is used in the waste heat recovery from the power plant circulating water is mainly explained,after adding heat pump then the waste heat is recycled fully,this all improve the power plant thermal efficiency,and the heating area is in- creased.

The scale of integration of the distributed photovoltaic (PV) into the power system is expand gradually with the characteristics of elimination on the spot,flexible operation,lower feeder power losses,et al.Voltage exceeding caused by the huge PV system generation in low-voltage feeders cannot be ignored any more.The purpose of this paper is to review the globe status of reactive voltage control strategies for overvoltage caused by large-scale distributed PV connected into the distribution network.The main contents include the control principle,mathematical model and control model of various blocks in distributed PV grid-connected system are briefly introduced,and analyses for the influences of higher PV generation and PV inverters’ reactive power to the reactive voltage are given.Finally,traditional and emerging reactive voltage control strategies are summarized respectively,and reviews of superiority-inferiority for each reactive voltage control methods are also given.

The characteristics of the chemical structure of the cellulose,hemicellulose and lignin,three components of biomass,were studied by nuclear magnetic resonance spectroscopy (¹³C-NMR).The results reveal that aromatic and aliphatic carbon-carbon ratio in cellulose was significantly higher than those in hemicellulose and lignin,5.2:1,1.9:1 and 1:1.2,respectively,which led directly to the difference of the pyrolysis products of the three components.Based on the previous studies,a chemical percolation (CPD) model for biomass devolatilization was established.The chemical structure of each component of biomass was studied by ¹³C-NMR,and four input parameters of CPD model were obtained.The pyrolysis yield of the three components were predicted.According to the content of each component in pine sawdust,the product yield of pine sawdust pyrolysis was calculated.

The landscape water in the north college was investigated from April to May of 2015 to evaluate the water quality and the eutrophication degree.The results showed that the content of total nitrogen(TN) and total phosphorus(TP) were high,the N/P was 2.6 that meant the landscape water was controlled by nitrogen,the organic pollution in water was not serious but had deteriorating trend.Meanwhile,the single factor index evaluation method,comprehensive water quality identification index method and comprehensive nutritional state index method were used to evaluate the water eutrophic state,and the landscape water is eutrophic water.The possibility of algae bloom greatly increases with the increase of temperature.

Large-scale energy storage system in the power system has been widely used.This article describes the current pumped storage,compressed air energy storage,superconducting magnetic energy storage,supercapacitors energy storage,energy storage and other energy storage technology development status,maturity,application and demonstration projects,analysis of the energy storage system economic evaluation and battery energy storage system in renewable energy applications.

Electromagnetic water treatment technology is a kind of physical methods of anti-scaling.It has attracted more and more attention because of no added reagents,non-toxic,non polluting,simple operation and low cost and so on.According to the researches of home and abroad,the influence of electromagnetic field on the crystallization process,crystal morphology and physicochemical properties of solution and the variation of the electromagnetic field parameters(like electromagnetic field intensity,frequency,direction,electromagnetic treatment time and velocity) on the anti-scale effect are reviewed.And on the basis of these,the paper introduces the progress of the research on the mechanism of electromagnetic anti-scaling and the problems to be solved.Finally,the development trend of the technology is prospected.

The conductor temperatures of power cables change with load current as well as thermal characteristic parameters of power cables and surrounding medium.For the safety and the economy of transmission,it is meaningful to accurately predict the transient state thermal field of underground cables.Determining conductor temperatures is the basis of improving the current-carrying capacity.The finite difference method has shown difficulty in dealing with circular boundary of power cables and rectangular boundary of the surrounding soil when calculating temperature field of power cables.In this paper,ladder straight lines are adopted to substitute circular boundary of power cables,and temperature fields as well as ampacity are solved in Cartesian coordinate system.Numerical calculation results of finite difference method,which are based on the combinatorial coordinate and the temperature rise tests of the constant as well as variable load current,have proved that the method presented in this paper is effective to calculate the temperature fields of underground cables.The ampacity of power cables is often determined by experimental test.The present experimental ampacity,and the temperature rise of power conductors of constant load current,are studied based on the method presented in this paper.The results show that the temperature rise speed of power conductors slows when the soil thermal resistivity and the power cables increase.The tested ampacity may be much higher than the real ampacity because of the thermal steady criterion used in the test.

This paper studies the definition and classification of voltage stability,introduce static and dynamic analysis method of voltage stability so far with a comprehensive analysis of voltage stability analysis method. The static analysis method include singular value decomposition method,the sensitivity method,the continuous power flow method and the collapse point method; the dynamic analysis method include Small perturbation analysis,time-domain simulation method,energy function method and bifurcation theory。And comprehensively analyze and evaluate analysis method of voltage stability. we summarize the feature of voltage stability analysis method and look into the future development direction.

The ocean is a huge energy depot,and each country in the world dedicate to the exploitation and utilization of ocean energy.Especially the ocean thermal energy conversion (OTEC) is concerned.In this paper,the way of power cycle and the influence of the working fluid characteristics on the cycle were analyzed emphatically based on the predominance and the development review of the OTEC domestic and overseas.Improvement of the net efficiency of the cycle is urgent because of lower thermal energy conversion efficiency for low-grade energy.Therefore,the measures to improve the net efficiency of the OTEC power cycle were discussed.Moreover the development prospects of the ocean thermal energy technologies were forecasted.

Study of oil sand pyrolysis by thermogravimetric analysis could guide the work of oil recovery by retorting.The pyrolysis experiments were carried out using thermogravimetric analyzer from room temperatwre to a final temperature of 550℃ under various heating rates.The results show that 350℃~520℃ in cracking stage is the main oil production region,where the TG weight loss data were in good agreement with the oil yields data by Fischer Assay.It's attributed to the cracking of heavy organic substances,especially bitumen.DAEM,FWO and C-R models were used to calculate the activation energy of oil production region respectively.The results implied that the pyrolysis of oil sand could be well described by DAEM and FWO models.The values of activation erengy approximately keep consistency with each other and are not constant throughout the chosen region within the range from 150 kJ/mol to 320 kJ/mol,then over the cracking process at about 220 kJ/mol.However,the C-R model which has been extensively applied in oil sand pyrolysis has unsatisfied with fitting results,the values of activation energy were significantly on the low side compared with DAEM results.The reason for the limitations of C-R model is that the chosen mechanism function is depended on a assumption of single elementary reaction,however,the process of pyrolysis in experiments is a complex heterogeneous reaction which is consisted of many elementary reactions paralleled,continued,overlapped or competed with each other.

Electronic nose is an intelligent instrument for gas detection in the complex environments.In this paper,we designed an electronic nose based on the Labview system,which integrated a variety of algorithms of pattern recognition,and it can be used for the detection of the samples with gas characteristic.The hardware of the system is simple,software is easy to operate,and low-cost.In this paper,we classified and tested four different kinds of edible oil and achieved a good recognition effect.

Because of the influence of engine system and working environment,the leakage of engine valves signal is proved to be non-stationary and non-stationary.In view of this characteristic,a fault diagnosis method based on improved Hilbert-Huang transform is proposed.The engine cylinder knocking sound signals as the research object.Firstly,these signals are pretreated by using the fast independent component analysis method to eliminate ambient noise.Then,with improved empirical mode decomposition method,the intrinsic mode functions are obtained and sensitive intrinsic mode functions are selected by correlation analysis method.Finally,the Hilbert spectrum and marginal spectrum of the signals are obtained with Hilbert transform.By combining the features of time domain and frequency domain,the faults can be diagnosed.The simulation experiment shows the effectiveness of the proposed method.The actual test shows that the Hilbert spectrum and marginal spectrum can display the physical information of the fault signals effectively and accurately.It also provides an effective method for this problem.

Oxygen containing functional groups is an important characteristic of coal macromolecular structure.In this paper,the research progress of oxygen-containing functional groups on the surface of coal were described,including the determination of oxygen containing functional groups on the surface of coal,the surface properties of coal and the effect of combustion.The research of the oxygen-containing functional groups of surface aimed to study the relevant features of coal from the coal structure and the change,and get a deeper understanding of coal,have a better grasp on the surface properties of coal,and then be more reasonable for the classification and comprehensive utilization of coal.

This paper puts forward the principle of the practice base for the selection of professional training features.To make the accomplishment of the three-dimensional materials auxiliary practice.Try a combination of on campus and off-campus mode practice,to practice by strengthening the organization and management,to improve students self-learning ability so as to establish the image of the school.Years of graduation practice has proved that it is a good practice model.

Biological wastewater treatment methods have been extensively applied in the treatment of municipal wastewater and industrial wastewater for its low cost, high efficiency, easy operation and free of secondary pollution when compared with the physical and chemical methods. Along with development of the modern compound industry, a variety of xenobiotics enter the municipal wastewater and the industrial wastewater, which poses great challenge to the conventional biological wastewater treatment. Therefore, application of bioaugmentation with the delivery of microbial agent to enhance the efficiency and the stability of the biological wastewater treatment processes received comprehensive concerns among researchers across the world. The present paper reviewed the mechanisms, efficiency and the status quo of bioaugmentaion in the wastewater treatment field. The prospects of bioaugmentation were also presented. It was anticipated that this paper would provide useful guidance for the development of microbial agent and the application of bioaugmentatation.

In order to assess the ash deposition on the serpentine and connected pipe of economizer in a 300MW pulverized coal bolier,a cold numerical simulation was carried out.The unidirectional coupling model was used to solve the gas paticle flow by ingoring the influence of the solid phase on the gas phase.The flow field was obtained and analyzed under the condition of given different inlet velocity and pitch.The results showed that the ash deposition about the four pipe on the bottom was serious in the parallel tubes.In the serpentine,the ash deposition about the four elbow on the top was serious and the abrasion was focused on the four elbow on the bottom.With the increase of flow velocity in the parallel tubes,speed curve steepened,and reflux zone decreased.At various points in the the serpentine,the velocity increased and the direction was constant.With the increase of pitch,the ash deposition on the parallel tubes was complex and the disturbance of fluid increased in the serpentine.

When the pipeline is in the same public corridor with the high voltage transmission line,it will be affected by the electromagnetic field,which is usually referred as AC electromagnetic interference.When the induced AC voltage produced by the interference is higher,it will threat the safety of the pipeline operation and maintenance staff.Therefore,It is of great significance to study the influence of the high voltage AC transmission line on the nearby pipeline and to judge whether it exceeds the limited value and to put forward the method reducing the electromagnetic effect and the Mitigation-Method.This paper selects section 10 transmission line and gas pipeline 3 between the Taizhou Station and the Suzhou Station of "Huainan-Nanjing-Shanghai 1000 kV UHVAC power transmission project" as the system model.We use CDEGS developed by Canada SES Company to simulate steady state disturbance on pipeline 3 caused by transmission lines under steady state operation and to analyze the induction potential distribution on the pipeline 3.The conclusion is that the induced voltage of the pipeline 3 at household entrance is higher than the human safety voltage limits,and we need to lay bare copper along the pipeline or take other protective measures.

Centralized photovoltaic(PV) power generation has the advantages of flexible location,output stability,flexible operation mode,short construction period and strong ability to adapt to the environment.However,large investment,long investment recovery period,and cost and efficiency difficult to calculate,make many investors discouraged.This paper establishes the cost and benefit model of centralized PV power generation under the life cycle,and introduces the carbon emission right transaction to quantify the environmental benefits of PV power generation into economic benefits,which effectively reduces the cost of electricity,optimize the economic evaluation index,and paper analyzes the different factors that affect the benefits of centralized PV power generation,and analyzes the economic benefits of centralized PV power more comprehensively and objectively.It provides a strong reference for more PV investment decision and PV grid pricing.

According to the characteristics of multivariable and multiple constraints and also nonlinearity which reactive power optimization possesses,the improved dual population ant colony algorithm is presented.It is found that the ant colony algorithm has the shortcomings of a long time search and easy to stagnation and so on except of many advantages.Therefore,the dual-population algorithm is introduced on the basis of the basic ant colony algorithm to conduct independent search,information exchange,greater probability of breaking the stagnation of a single ant colony search to ensure the diversity of the solutions in the algorithm and enhance the capability of global convergence.The improvements in the pheromone update strategy and parameters of the ant colony algorithm are applied to reactive power optimization.It verifies that the algorithm is effective by means of the simulation of IEEE30 node and the comparison of existing algorithms.