bluuebunny/crossref_metadata_2025 huggingface dataset:
Building’s solar chimney: The performance of width and inlet to in tropical country
Authors: Abraham S B , Ming T Z
Published: October 2019

The main purpose of the passive solar design strategy is to maximize the potential for abundance of solar radiation to improve the heating/cooling of buildings. One of them is by utilizing the stack ventilation strategy. Solar Chimney (SC) is a technology that utilizes this effect. Further simulation of Abraham’s research on buildings with SC such as widening the chimney and the opening/closing strategy of the inlet to test the performance of the inlet. The results showed that changes in the variation in width and angle of the solar chimney effectively increased the value of indoor wind speed by 10%. Whereas through the inlet open/close strategy it can be seen which inlet has the best performance.
Photovoltaic-thermal (PVT) technology: Review and case study
Authors: Ramos C A F , Alcaso A N , Cardoso A J M
Published: October 2019

Nowadays, solar technology converts solar energy into electricity and heat separately. For electricity generation, the main obstacle is the fact that the photovoltaic cells produce less energy as the temperature increases. To overcome this, cooling techniques can be used to raise the efficiency of solar cells, in order to obtain greater power generation. The photovoltaic-thermal hybrid solar collector (or PVT) is an equipment that integrates a photovoltaic (PV) module, for the conversion of solar energy into electrical energy, and a module with high thermal conversion efficiency (T), which employs a thermal fluid. This optimization of solar conversion technology has the main objective of cooling the photovoltaic cells, for increased generation of electricity, while also resulting in useful thermal energy from the working fluid, therefore constituting a cogeneration equipment. The present work reviews the development and global panorama of PVT technology. Afterwards, a case study of a PVT system is presented, together with a theoretical and experimental study. A thermography analysis performed in this PVT system is also examined, which allows for a real-time study of its operating regimes in different conditions, mainly of its thermal behaviour, and for the diagnosis of hot spots that signal potential defects in the cells.
Study on environmental legal systems of different regions in China and impact on energetic cooperation
Authors: Zhang J D
Published: October 2019

Based on the present situation of China’s environmental law system under the rapid economic development, this paper expounds the significance of regional environmental law research. Through the comparison of regional environment and legal system between China and the United States, this paper analyzes the impact of domestic environmental legal system on energy cooperation under the background of Belt and Road Initiative.
The joint simulation of doubly-fed wind turbines
Authors: Xiao Y C , Chen W J
Published: October 2019

As a clean and safe renewable energy, wind power has been rapidly commercialized in recent years. In order to analyse some faults in wind turbines by software, a joint simulation model of 1.5 MW doubly-fed wind turbine is built in this paper. In the system, the 3D model of the transmission system was established by SolidWorks, which was imported into Adams to build the virtual prototype model. The other parts of the system are built by MATLAB/Simulink. Thus the advantages of Adams in mechanical multibody dynamics and MATLAB/Simulink in wind turbines control system are combined. The simulation result of the wind turbine output power under natural wind speed proves the validity of the model.
Experimental study on heat transfer resistance of condensation heat transfer in high efficiency heat transfer
Authors: Ma L X , Lu K
Published: October 2019

The condensation heat transfer experiment of R134a inside the horizontal enhanced tube was operated under the condensation temperatures of 35°C, 40°C and 45°C. Firstly, correlations were used to predict the heat transfer coefficient inside the tube to check the experimental data reliability. Then mass flux and condensation temperature were selected as the variables, and the total heat transfer coefficient K, the water heat transfer coefficient hw and the refrigerant heat transfer coefficient hr were seen as performance evaluation index to study the heat resistance of the enhanced tube. Experimental results show that: both the total heat transfer coefficient K and the refrigerant heat transfer coefficient hr increase with increasing mass flux, and get bigger with temperature decreasing. But the water heat transfer coefficient hw slightly decreases with mass flux increasing. And condensation temperature has a small influence on it. Analyze the thermal resistance and find that the water thermal resistance increases and the refrigerant thermal resistance decreases with mass flux increasing but the refrigerant thermal resistance is always less than the water thermal resistance. The difference between them gets bigger with the temperature decreasing.
Wind power control strategy based on high precision prediction technology
Authors: Liu Q , Zhao J , Zhang S F , Wu J , Fang JJ , Wang L H , Shao Y G
Published: October 2019

This paper proposes an active power control strategy for wind farms based on high-precision prediction technology. The aim of this study is to improve the absorptive capacity of large-scale wind farms, reduce network loss and promote the operation economy of wind farms. The strategy divides the active power dispatching into four layers. Based on the constraints of the safe operation of the power grid, the corresponding objective function and power allocation method for each layerare given. The result of this study shows that the strategy proposed can effectively improve the operation economy of the power grid and promote wind power consumption. Compared with the traditional control strategy, the proposed control strategy can well deal with the actual situation of large power fluctuation, and reduce the number of wind turbine start-up and shutdown.
Feasibility study of a coal-fired coupled to biomass power generation technology on a 300 MW unit boiler
Authors: Sun W , Wang Y , Liu G D , Li Y L
Published: October 2019

This paper describes the characteristics of a coal-fired coupled to biomass power generation technology on a 300 MW unit boiler, the characteristics of the coal-fired coupled to biomass fuel, and the problems and solutions that may occur in the process of coal-fired coupled biomass power generation, as well as the boiler technology transformation plan on the coal-fired coupled to biomass power generation. In terms of study on the characteristics of coal-burning coupled to biomass fuel, the main characteristics of the coal-burning coupled to biomass fuel, such as the combustion characteristics, the ignition characteristics, the burnout characteristics, the slagging characteristics, and the explosion characteristics of the coal-burning coupled to biomass fuel are described. The paper mainly describes the explosion prone problem of the pulverizing system, the pulverized coal hardening problem of the raw coal bunker and the boiler corrosion, and coking problem of the heating surface of the boiler. The explosion-proof transformation of the pulverizing system is described, and the technology transformation of the pulverizing system is carried out. After adopting the technical transformation scheme of sludge, the problems caused by sludge blending and burning are solved, and the power generation by sludge blending and burning is realized.
Selection of steam turbine bypass system
Authors: Sun W , Wang Y
Published: October 2019

This paper introduces the functions of steam turbine bypass system for the large coal-fired power units, the types of the steam turbine bypass system, the selections of the bypass system capacity and the current design situation of domestic units. About the functional design of the steam turbine bypass system, it is designed with the following functions: starting, protecting the reheater, tracking the main steam pressure, recovering working substance, quick opening when the steam turbine trips, relief valve and fast cut back etc.. About the type of bypass system, this paper introduces the application of the bypass system for large capacity units, which can be divided into four types: the high pressure one-stage large capacity bypass system, the high and low pressure two-stage series bypass system, the tertiary bypass system and the triple-purpose valve bypass system, and the advantages and disadvantages of the design for all kinds of the bypass system. In terms of the capacity selection of the bypass system capacity, the capacity of the bypass system should be selected to match the peak-regulation capacity of the unit, while taking into account the investment and maintenance costs. In view of the current design situation of domestic units, this paper expounds the design patterns and the characteristics of the bypass system of several large thermal power units.
Quantitative detection of trace H2S based on ultraviolet differential optical absorption spectroscopy
Authors: Li H T , Zhao K , Ma Y , Jia Y Y , Liu Y F , Gao S , Song S Q , Zhang X X
Published: October 2019

As an important decomposition component of SF6, H2S can provide an important information for the evaluation of insulation state of SF6 gas insulated equipment. Since H2S has obvious absorption in the ultraviolet (UV) range of 190∼230 nm, the UV absorption spectrum detection platform is established to realize its detection. In this paper, SF6 decomposition component detection platform based on UV spectroscopy was built, and the UV absorption spectrum of H2S was obtained. Since the UV absorption spectrum directly obtained by the instrument is susceptible to spectral scattering and high frequency noise, the detection sensitivity is low. Therefore, this paper uses the UV differential algorithm to obtain the UV absorption spectrum of H2S. After experimental tests, the R2 of the fitted line is as high as 0.999. Moreover, the method has good repeatability for detection of H2S, the results show that the absolute error does not exceed 0.2 μL/L. The noise is calculated by randomly collecting 30 sets background spectrum, and the detection limit is 0.590 μL/L when the signal-to-noise ratio is 1. A method for detecting H2S gas concentration based on UV differential absorption spectroscopy is proposed, which is suitable for on-line monitoring of trace H2S in the decomposition components of SF6 gas insulated equipment.
Profit sharing method based on weighted Shapley value under government regulation
Authors: Yu L L , Li T T , Liu W X , Yuan P , Shao H B , Wang Y , Wang Z Q , Zhou S C
Published: October 2019

With the diversification of power market users, reasonable profit distribution among members becomes the focus of government regulation. Under the background of demand-side liberalization, with the introduction of “peak-regulating device” represented by battery, the member operation characteristics of small and medium-sized power users become more and more complex, and the traditional method of profit allocation based on power generation assessment is no longer applicable. In order to solve this problem, this paper proposes a profit-sharing method based on weighted Shapley value, which takes the contribution of marginal conditional value-at-risk under the participation of small and medium-sized users as the weight to improve the traditional Shapley value method. An example is given to illustrate the feasibility and rationality of the improved method.
Numerical simulation of wind farm flow field
Authors: Qin T , Zhang X D , Wang Y K , Cai B , Han Y , Yu Y L
Published: October 2019

Because of its high accuracy can be achieved and can reduce the gold investment, CFD calculations are widely used in wind farm construction projects. This paper uses the solver buoyantBoussinesqSimpleFoam of the open CFD software-OpenFOAM to simulate the wind farm. First, we use the flat terrain and homogeneous Atmospheric Boundary Layer (ABL) flow, corresponding to the atmospheric boundary layer of a neutral state, stable state and unstable state was established three groups of numerical simulation models to correctness of the models. The results show that the three models used in this paper have ideal simulation results for the atmospheric boundary layer, and can accurately calculate the atmospheric boundary layer containing temperature and buoyancy effects. By comparing the calculation results of Askervein Moutain and Bolund Island with the experimental data, it is found that: The calculation model and solver used in this paper can better calculate the wind resource distribution under complex terrain conditions, and the calculation results are accurate, which is in good agreement with the experimental values.
Thermochemical upgrading of coconut husk and rubber seed to coal co-firing feedstock via torrefaction
Authors: Lee Y T , Ng H K , Gan S , Jourabchi S A
Published: October 2019

This research seeks to investigate thermochemical upgrading of Malaysian coconut husk and rubber seed to coal co-firing feedstock via torrefaction. Torrefaction experiments within a range of temperatures (200-300°C) and holding times (30 and 60 min) were carried out using a tubular furnace. Mass yield, higher heating value (HHV), energy densification ratio (EDR) and energy yield as well as proximate analysis were determined for the torrefied biomass sample. Both torrefaction temperature and holding time decreased the mass yield and the energy yield of the torrefied biomass. The HHV and EDR of coconut husk and rubber seed increased upon torrefaction. The VM decreased while the FC increased after torrefaction. Rubber seed torrefied at 300°C and 60 min had a HHV of 29.22 MJ/kg which was comparable to that of bituminuous coal. Linear correlations (R2=0.7764-0.965) were developed between mass yield and EDR, as well as mass yield and energy yield. Up to 70 wt% and 60 wt% of coal with a fuel ratio of 1 could be replaced by coconut husk and rubber seed torrefied at 300 °C and 60 min, respectively. Overall, the study indicated the feasibility of torrefied rubber seed (300°C and 60 min) as a coal co-firing feedstock in comparison to torrefied coconut husk due to its higher HHV cum lower ash content as well as its high co-firing proportion with coals having fuel ratio of at least 1.
In-situ continuous growth of carbon nanotubes on the surface of carbon fibres
Authors: Qin J J , Wang C G , Wang Y X
Published: October 2019

An efficient method for growing carbon nanotubes (CNTs) on the surface of continuously moving carbon fibres has been developed by a unique open-ended chemical vapor deposition (CVD) furnace. Scanning electron microscopy (SEM) is used to observe the morphological characteristics of CNTs grown on carbon fibre surfaces, and high-resolution transmission electron microscopy (HRTEM) is used to study the microstructure of CNTs. The results show that the CNTs achieve uniform and orderly growth. In the process of CNTs growth, the cross-linking of adjacent graphite crystallites is formed and the damage of the catalyst nanoparticles to the fibres is repaired, so the tensile strength is increased compared to the carbon fibres undergoing reduction. CNTs-grown carbon fibres can be used to fabricate the flexible supercapacitor electrodes to improve electrochemical capacitance and promote electrochemical stability.
Maximum power point tracking control of photovoltaic power generation based on boost circuit
Authors: Li K , Cheng H X
Published: October 2019

In order to find an effective way of improving the power generation efficiency of photovoltaic solar panels, this paper discusses how to maximize the power point tracking control of photovoltaic panel power generation so that the panel is always output with the maximum power. This paper starts with an introduction of the working principle of maximum power point tracking (MPPT) and then compares several common methods of MPPT. After analyzing and comparing these methods, the most practicable and effective one is finally determined, which is the incremental conductance (INC) based on boost circuit. In this paper, modeling and simulations are carried out to prove the correctness and reliability of this method.
Analysis of line loss status and loss reduction measures in eastern Inner Mongolia Area
Authors: Lu J Q , Lan Y , Ren Z , Zheng T T , Wang J F , Zheng B W , Gao H
Published: October 2019

Loss reduction, energy saving, safe and stable operation of power grid are two major themes of power companies, among them, line loss is a comprehensive technical indicator for measuring and assessing the production technology and management level of power supply enterprises. It is also a comprehensive indicator for evaluating the operation level and production level of power enterprises. The loss is the inevitable cost of the power grid when transmitting power, which related to the planning, operation level and operational efficiency of the power grid, the calculation and analysis of the loss can effectively indicate the direction for the next step of the power grid and provide effective guidance for the economic operation of the power grid.
Fault Diagnosis of Mine Fan Bearing Based on Beetle Antennae Search
Authors: Che X Q , He H , Liu C Y , Sun H N , Bian L
Published: October 2019

Mine fan is the lifeblood of coal mine safety production, which plays an important role in ensuring the safety of the lives of mine workers. Once it fails to operate, it will cause irreparable serious consequences. Therefore, in order to ensure the safe operation of mine fan, this paper takes the common motor bearing faults in fan faults as the object of study, proposes a method of using rough set attribute reduction combined with Beetle antennae search to optimize BP neural network to establish diagnosis model, and compares it with genetic algorithm, particle swarm optimization, imperial competition algorithm and ant lion optimization algorithm. The experimental results show that the method achieves 90% accuracy in fault diagnosis of mine fan bearing, and has faster convergence speed and shorter operation time. Compared with other optimization algorithms, the method has greater advantages. After many tests, the diagnosis results are stable, which proves that the method is feasible and effective in fault diagnosis of mine fan.
Quotation and operation optimization of VPP in medium and long term market
Authors: Wang Z Q , Deng F Z , Bai H K , Yang M
Published: October 2019

Due to energy shortage and environmental pollution, distributed energy resource (DER) has been pouring into the grid, but its output is intermittent and fluctuant, which affects the operation of power grid. “Virtual power plant (VPP)” provides a channel to solve this problem. In this paper, VPP including distributed power supply (photovoltaic, wind power and gas turbine) and energy storage system (energy storage battery) is taken as the research object. Based on the uncertain factors such as season-of-use price, light intensity and wind speed, the VPP bidding strategy and operation scheduling strategy in the medium and long term contract market are studied, and the risk value model is applied to risk management. The example testing results show that, when quoting, the maximum loss caused by electricity price is generally within 5%, which is an acceptable risk; in operation, the gas turbine plays a major role in balancing the output deviation, and the VPP operation scheduling strategy has certain economic benefits.
Experimental Study of Smoke Deposition in the Case of Leakage Joint at the Bottom of Circular Utility Tunnel
Authors: Liu H N , Zhu G Q , Liang Z H , Zhou X
Published: October 2019

In order to obtain the relationship between the height of smoke layer and time in the case of fire with small leak at the bottom of circular utility tunnel. In this paper, diesel was used as fuel to conduct three small-size experiments in the utility tunnel. Based on the work of predecessors, the formula for the deposition of smoke suitable for circular utility tunnel was obtained. The results of the study are as following: 1) The highest temperature appears near the ceiling directly above the fire source. The temperature below the location of the hydraulic jump was very low and the temperature presents an obvious stratification phenomenon; 2) By comparing the calculating value with the experimental value, it is suggested that the equation can predict the change of smoke stratification height with time; 3) The horizontal spreading process of smoke in the ceiling is neglected, and the lower air cross-section area is treated approximately, which is the main reason for the difference between the calculating value and the experimental value.
Energy supply and Strategy of Core Urban agglomeration—taking Guangdong-Hong Kong-Macao Greater Bay Area as an example
Authors: Qin Y , Yu P
Published: October 2019

With the proposal of Guangdong-Hong Kong-Macao Greater Bay Area, its development is bound to become a world-class economic bay area that our country should pay attention to. However, the Greater Bay Area is located in the Pearl River Delta, where the energy is scarce and the economic development cannot be separated from the supply of energy, so solving this contradiction is a problem that cannot be bypassed in the development of the Greater Bay Area. Under the background of advocating energy-saving and environmental protection and green development, the energy utilization in Guangdong-Hong Kong-Macao Greater Bay Area is more and more important. Based on the analysis of the energy predicament in the Greater Bay Area and the energy strategy of Japan and the United States, this paper puts forward some ideas to solve the energy dilemma in the Greater Bay Area.
Artificial intelligence design research on the cyber security penetration testing of power grid enterprises
Authors: Sun X D , Ren Z , Yang P W , Li J , Chen H Y , Liu T Q
Published: October 2019

This paper introduces the key components of Artificial Intelligence (AI) expert system. It studies the main application of AI technology in network security. It deeply analyzes the network security situation of power grid enterprises, as well as the main problems in the troubleshooting and verification of vulnerability. The AI penetration test expert system is designed, and the implementation of the system is elaborated.
Research on APF Improved Control Strategy Under Three-phase Voltage Distortion
Authors: Lan Y , Lu J Q , Wang D , Zheng T T
Published: October 2019

At present, the most commonly used harmonic current detection algorithms are the p-q algorithm and the ip-i
q
algorithm based on the instantaneous reactive power theory. The premise of using the above algorithms is that the three-phase voltage is the ideal sinusoidal voltage. However, harmonic pollution distorts the voltage of the power grid to different degrees, which will affect the detection accuracy and compensation effect of APF. This paper presents a current detection algorithm based on positive sequence fundamental wave extractor, which can avoid the detection of positive sequence fundamental wave voltage of power grid, and can effectively avoid the shortcomings of p-q algorithm and ip-iq
algorithm without using PLL, complex coordinate transformation and low-pass filter. In the current control algorithm, according to the characteristic that the gain of the generalized integrator is infinite when resonance occurs, the sinusoidal and cosine instructions can be tracked without static difference, this paper which is based on the generalized integrator adaptively adjusts the coefficients of the generalized integrator to improve the robustness of the current controller. Finally, the simulation model is established by MATLAB, and the simulation results show that the improved harmonic current detection algorithm and control algorithm are advanced and effective.
Changes on structural and electrical properties of retired cross-linked polyethylene (XLPE) cable insulation under electro-thermal aging test
Authors: Huang J S , Lu R G , Shi Y X , Zhao Y F , Huang J X , Fang X H , Liu G , Li Z J
Published: October 2019

In order to study the insulation performance of two retired high voltage cross-linked polyethylene (XLPE) cables with service years of 16 and 32 and evaluate the reliability of reusing these cables for actual operation, a 180-day electro-thermal aging test was exerted on a section of these two cables to inspect the changes on structural and electrical properties. Several diagnostic measurements including fourier infrared spectroscopy (FTIR), differential scanning calorimetry (DSC) and breakdown field strength were carried out on the untreated and treated samples. The measured results show that the crystalline structure of the 16 years cable has been improved after the accelerated aging test probably because of the reduction of the impurities and the annealing effect, which further improve the electrical property. Even though the molecular chains of the 32 years cable insulation has been damaged and a slight degradation happens on the crystalline structure under the intensive aging test condition, which is responsible for the decline in the electrical property, the cable still have the potential to resist the stresses properly under the actual operation condition for a long time from the perspective of the XLPE. Therefore, it can be expected that the rest of these two retired cables still have the ability to reuse in the long-term actual operation condition.
Effective steady-state security regions of power systems considering voltage magnitude
Authors: Zhou Y , Yang X L , Yang M , Zhu Y , Wang C , Bo Y F , Du P J
Published: October 2019

With high-level variable renewable energy integrating into power systems, the uncertainty significant challenges to the real-time dispatch (RTD). Meanwhile, the influence of voltage magnitude and reactive power on RTD always were ignored. Based on effective steady-state security regions of power systems and linear power flow model, a real-time dispatching method considering voltage magnitude and reactive power is proposed in this paper. This model has two goals, one is the security goal, the other is the economic goal, and priority of security objectives is higher than economy. Unlike previous real-time dispatch methods, all of the operation base point, reactive power output and participation factors of automatic generation control (AGC) generators are chosen as decision variables in the model. In order to ensure computational efficiency, the model is finally transformed into a deterministic linear programming (LP) problem by robust optimization and other methods. The accuracy and computational efficiency of the method are illustrated by modified IEEE 9-bus system and IEEE 118-bus system.
Short-term forecasting of electric load based on Kalman filter with elastic net method
Authors: Tian Y J , Shen H X , Gao W G
Published: October 2019

The short-term forecasting model based on Kalman filter is an important class of predictive algorithm widely used. This paper discusses a self-adaptive Kalman filter. The main idea of the paper is applying elastic net method and covariance matrices estimation to parameter identification, which can select variables of state with linear regression to make the model close to reality. Finally, this paper gives a simulation experiment to prove the effectiveness and feasibility of the model in practice.
Study on the Adjustment of the Network Interface for the Station Domain Protection Device Based on RTDS
Authors: Wang G N , Pan B R , Gui X Z , Xie G Q , Zhou S H , Zheng X
Published: October 2019

With continual development of smart grid construction, digital substation devices based on the specification IEC 61850, such as substation-area backup protection, have been widely applied. According to the “Technical requirements for the substation-area backup protection control device of the new generation of intelligent substation”, this paper put forward the debugging scheme of all digital network interface based on RTDS. Through the introduction of the RTDS software and hardware platform of the whole process building and commissioning, and by constructing substation simulation model and configuring GTNET-GSE card and GTNET-SV card, a closed-loop test system of substation-area backup protection device is completed, also this process development verification interface debugging method and configuration files have a certain practical value. The simulation of substation typical fault conditions and device data receiving processing mechanism can effectively meet the state grid enterprises standard Q/GDW11053-2013 for protection device test project requirements, and this test can significantly improve the smart substation integrated debugging efficiency.
Anomaly detection for wind turbine gearbox oil pressure difference based on SCADA data
Authors: Bo Y F , Zeng X J , Yang M , Zhu Y
Published: October 2019

In this paper, a SCADA data-based fault detection method for gearbox oil pressure difference is proposed, and the core of the method is Spare Bayesian Learning (SBL) algorithm. The gearbox oil pressure difference probability estimation model can be constructed by training the historical normal operating based on SBL. Then, the probability distribution interval of the gearbox oil pressure difference can be estimated. The abnormal state of gearbox oil pressure difference can be judged by observing whether the actual value within the probability distribution interval. In addition, statistical hypothesis testing method is used to verify the reliability of the anomaly detection results. Through the method, the gearbox oil pressure difference anomaly detection problem can be transformed into a parameter estimation problem with low computational complexity. Case studies are conducted on two actual WTs with known gearbox oil pressure difference faults, and the results demonstrate the feasibility and effectiveness of the method.
Calculation and application of surface nominal electric fields of ±1100 kV UHVDC power lines
Authors: Li X J
Published: October 2019

Electric field strength is one of fundamental electromagnetic environmental parameters for the design of ultra-high voltage direct current (UHVDC) power lines and towers when considering human exposure and transient shock. In order to investigate the impacts of power lines’ geometric parameters on the nominal electric fields on the surfaces of ±1100 kV UHVDC sub-conductors, charge simulation method is used for calculations. The algorithm is verified by both verification nodes’ potentials in the process and measurement experiments in the laboratory. The geometric parameter of sub-conductor radius has the most obvious effect on the field. When the radius varies by 10%, the electric field strength on the sub-conductor’s surfaces may change approximately by 8%. Calculation results demonstrate that increasing sub-conductor radius may be most effective measure to restrict the electric field on the ground.
Research on the Influence of Wind Characteristics on Output Characteristics of Doubly - fed Wind Turbines
Authors: Bai Y P , Wang D , Yang P W
Published: October 2019

The inherent randomness and intermittence of wind power will make it difficult to accurately predict the output of wind farms and the regulation and stability of power grids. As the output power of the turbine is proportional to the third power of the wind speed, tiny variation of the wind speed will cause much larger fluctuation of the turbine output. With the construction of wind farms gradually moving to non-wind resource-rich areas such as mountainous areas, wind turbines have to face more pulsating wind and greater turbulence intensity. In this paper, based on field measurement data and Generated wind conditions, a doubley-fed wind turbine simulation model was built to simulate the influence of different wind condition variations on the output characteristics of the doubly-fed wind turbines. The response of wind turbines to pulsating wind speed is analyzed by using the step response module to simulate the characteristics of wind. By dividing three different working intervals of wind turbine, the influence of different turbulence intensity on the output characteristics of wind turbines is analyzed. The simulation results have theoretical significance for improving the accuracy of wind turbine output prediction and wind turbine optimization design.
Evaluation of photovoltaic power station operation under the influence of natural environment
Authors: Zhang J H , Miao S H , Li Y W , Zhang D , Guo S Y
Published: October 2019

This paper presents a method for evaluating the operation statute of photovoltaic power plants. It considers the impact of various kinds of natural environment. Firstly, by analysis the impact of different natural factors on photovoltaic power generation, we can find the most influential factors that affect the output of photovoltaic power station. Secondly, use these factors as a standard to separate the natural environments into different kinds. Thirdly, use the AHP method to establish an indicator evaluation system and multiple indicator weight determination methods for different environments. Then, setting proper formula to evaluation the operation statue of photovoltaic power station. Finally, in part 7 a case is proposed to illustrate the present method.
Production calculation model considering variable start-up pressure gradient in ultra-low permeability reservoirs
Authors: Li C L , Zhang Y
Published: October 2019

Ultra-low permeability reservoir fluid presents nonlinear flow, pressure sensitive effect, permeability changes, resulting in starting pressure gradient changes. At present, the problem of variable-start pressure gradient and pressure-sensitive effect is not considered in the existing production calculation method. To solve these problems, based on the percolation theory of ultra-low permeability reservoir, this study established the variable-start pressure gradient production calculation model based on the pressure sensitivity effect by using the pressure-sensitive effect formula and other laboratory experiment results. Taking Block C of Chaoyanggou Oilfield as an example, the main influencing factors of development effect under the condition of variable start-up pressure gradient are analyzed. The results show that the start-up pressure gradient leads to a significant decline in oil well production. When the variable start-up pressure gradient and pressure sensitive effect are considered simultaneously, the effective production radius of the oil well decreases, and the production of the oil well varies nonlinearly with the change of pressure. Compared with the calculation results of the non-Darcy seepage production model, the calculation accuracy of the model in this paper is improved by 4.17%.
U.S. Renewable Energy Policy: The Experience of Advanced Research Projects Agency-Energy
Authors: Qian X M
Published: October 2019

ARPA-E is playing an important role in developing revolutionary energy technologies that may impact US energy status. The role has become a powerful engine for new energy innovation in the United States. ARPA-E adopts a very flexible organization and management mode, and its operating mode has become a model for small organizations within the US government. In order to strengthen ARPA-E, the U.S. government has increased investment in recruiting talents, team culture, and technology research and development. The ARPA-E project in the United States has formed standardized procedures, systems and regulations in the management of new energy research projects, and can effectively and efficiently implement these contents, forming management characteristics and playing a high reference role for other countries’ new energy research and development.
Modeling of Vertical Dynamic Vibration Characteristics on Vehicles Suspension System
Authors: Ka’ka Simon , Himran Syukri , Renreng Ilyas , Sutresman Onny
Published: October 2019

Vibrations often interfere with driving comfort for riders and passengers. Variations in loads, especially for four-wheeled vehicles, bumps, hollow road surfaces, and other forms of road damage will greatly affect the vehicle suspension work system. This research aims to (1) further test the effect of vertical dynamic load of the vehicle and change the dimension of resistance on the road surface, (2) the contribution of spring and shock absorber to the load fluctuation of the vehicle. Experimentally these load fluctuations are replaced by pneumatic actuator forces of varying magnitude based on the regulatory pressure of the regulator. The deviations generated by the varying load work are measured by placing a proximity sensor along the spring movement. The vertical dynamic load transformation up to the road surface is measured using a "Load cell" mounted under the wheels of the vehicle. Characteristics of vertical dynamic vibration occurring due to several dimensional barriers, U (cm) obtained using mathematical modeling method with 2 DOF suspension system transfer function. The results showed a condition on the body and wheels of vehicles experienced a brief overshot for 0.14 seconds with deviation of 0.178 m. From the graph shows that the rate of deviation that occurs is large enough that Y2d = 1.03 m / s caused by a sudden shock that occurred on the wheels of the vehicle. This condition does not last long that is only duration t = 0.22 s, because the contribution of springs and shock absorbers that can absorb vibration is 25% to the vibrations caused by the vertical load of the body and the axis of the vehicle.
Enviromental Geochemistry of Bawakaraeng Mountain Soil: Implication for Anthropogenic Impact Gowa South Sulawesi Indonesia
Authors: Tonggiroh Adi , Syam Rafiuddin
Published: October 2019

Determination of heavy metal are done on Mount Bawakaraeng soil to find out the impact of anthropogenic, using range proximity matrix independent variables on camps, fired, garbage. There are two concentrated heavy metal zone and two particular zone (sample point 29, zone I; sample point 3 and 5, zone II) as concentrated heavy metal on rocks fractures, lavene statistic probability show the source of heavy metal Cr are different. Surface soil samples are taken on mapping variable, forest fires, especially for top and bottom of soil only garbage variable are taken. Furthermore, using Inductively Coupled Plasma Oscilloscope Emission Spectrometer (ICP-OES), X-Ray Fluorescence (XRF). Rock Samples analysis are done using thin section method on polarized microscope to find out the composition of volcanic minerals. EF range are higher and lower than 2 are showing the enrichment of heavy metal are naturally formed and EF relatively moderate by human activities. (Igeo) camp are Cr (0.606), Cu (0,529), Mn (0.383). Zn (0.590) Cd (-0.779). Pb (0.440); fired are Cr (0.586), Cu (0.514), Mn (0.383), Zn (0.590), Cd (-0.770), Pb (0.447); garbage is Cr (0.584), Cu (0.461), Mn (0.343), Zn (0.579), Cd (-1.110), Pb (0.458). the difference of EF and Igeo value are affected by sample point 3;5;29 and indexes value 1.5 on volcanic rocks soil. Friedman test are showing relatively small differences between human activities and nature factor, which indicating that Bawakaraeng Mount morphology are easily affected by exogenic and endogenic factors.
Beneficiation of Lateritic Iron Ore from Malili Area, South Sulawesi, Indonesia Using Magnetic Separator
Authors: Sufriadin  , Widodo S , Trianto M
Published: October 2019

The increasing demand of sponge iron as raw materials in steel industry nowdays has led to increase the effort in obtaining such materials from various sources. This study aims to characterize and beneficiate of a lateritic iron ore sample from Malili area of South Sulawesi. Mineralogy of the ore was investigated by means of X-ray diffractometry (XRD) and microscopy techniques; whereas chemical composition of the sample was determined by using X-ray fluorescence (XRF) spectroscopy. Result of mineralogical analysis indicated that ore sample consists of goethite, magnetite and chromite. The ore shows fine grained size with accicular texture. Chemical analysis reveals that sample is composed of Fe2O3 32.8%, Al2O3 35.5%, SiO2 21.0%, Cr2O3 7.2%, MnO 1.5%, and NiO 1.2%. Sieving of 20 kg iron ore sample was carried out to separate into five size fractions: (+212)μm, (-212+180)μm, (-180+150)μm, (-150+90)μm and (-90)μm with mass distribution of 12.0kg; 2.8kg; 0.9kg; 1.8kg and 1.6kg respectively. Each feed fraction was further treated by using dry low-intensity drum magnetic separator to produce concentrate. Result of each fraction having the mass percentage of 15.5%; 31.7%; 30.7%; 32.0% and 40.0% with the respective iron content (Fe2O3) of 45.0%; 47.9%; 43.9%; 46.7% and 47.2%. The Fe2O3 grade of concentrate in all fractions have narrow range values, but the mass percentage of concentrate increase significantly with finer grain size fraction. The highest Fe2O3 recovery was found to be 89.82% with -90 μm size fraction.
Car Driver Drowsiness Recognition Android-Based System
Authors: Indrabayu  , Mufti Siti Khumaerah , Areni Intan Sari
Published: October 2019

The growth of the number of vehicles in Indonesia especially in terrestrial mode is also offset by the increasing number of accidents. One of the main causes of traffic accidents is due to drivers who driving in drowsiness. This condition leads to loss of concentration and even awareness of the driver. The drowsiness recognition system built into android smartphone platforms which owned by almost all walks of life, can help the community and government in providing direct warning especially to motorists while driving in a drowsy state. The method used is the Haar-Cascade Classifier to detect the driver's face and utilize the detectable face size ratio to create ROI in the mouth area. Then the using of the FindContour algorithm to find contours in dark areas when the mouth is open because it evaporates. The size of the contour will be compared to the Mouth ROI size for the drowsy driver's decision. System creation using Android Studio with C ++ and Java programming languages, as well as OpenCV libraries for Haar-Cascade and FindContour. Based on the test to 10 respondents, the accuracy of the system recognizes sleepiness on the driver reached 88.7% during the day.
Audial comfort optimalization of The Lanraki Biringkanaya Makassar Church room
Authors: Ishak Muhammad Taufik , Asniawaty  , Sulistyowati Dwi Retno
Published: October 2019

Church is one of the unique worship buildings which is full of audial activities such as speech, songs, and music. The purpose of this research is to evaluate and give redesign suggestions so that the audial comfort in the church room can be achieved. Quantitative research method by analyzing data with the statistically-descriptive. Reverberation time was calculated by the Sabine formula, redesign using Autodesk Ecotect Analysis 2011 program, and the questionnaire processed by IBM SPSS Statistics 25 program. The results conclude that the sound pressure level distribution has been spread evenly, while the background noise and the reverberation time in the church room still exceed the standard. But overall, the user has felt comfort with the condition of the audial church room. So, we made change of materials and furniture that may affect the value of reverberation time and background noise in a room. We hope this research can be a reference to design the next church or similar buildings.
Experiments on Motion and Oscillation Controls of a Gantry Crane System Using Parallel Proportional Controllers
Authors: Muhammad A K , Tandioga R , Ka’ka S , Lewi L , Rahman A , Taufik A
Published: October 2019

The purposes of this research are to formulate the mathematical model of the system, to propose an effective control scheme and to perform experiments on a laboratory scale. The system used in this paper consists of a trolley, a pendulum as load and a dc motor to drive the trolley. Mathematical model of trolley position and load angle were formulated considering voltage of the motor and damping constant of the air calculated specifically using energy balance. Two proportional (P) controllers were designed in parallel in such a way to drive the trolley and to reduce oscillation of the load. The system and the proposed control scheme were confirmed through experiments. The experimental results revealed that the motion and oscillation of the system can be controlled effectively.
Experimental study on the influence of draft relative due to wave transmission energy coefficient on hanging sheet pile breakwater
Authors: Paotonan Chairul , Rahman Sabaruddin , Umar Hasdinar , Rachman Taufiqur , Baeda Achmad Yasir , Agustinus M , Hidayat Alif
Published: October 2019

Rubble mount breakwateris recently become the most widely used breakwater, consist both of natural and artificial stone. It required a large dimension of structure so that the investment costs become more and more expensive. One of the solutions that can be implemented is Hanging Sheet Pile breakwater. Unfortunately, the performance of this type of breakwater has not been known yet. Performance of this breakwater represented by wave energy transmission coefficient (KEt). Therefore, this study aims to examine the effect of relative draft (s/d) and relative wave height (H/s) to KEt. This study conducted in Ocean Technology Laboratory of Universitas Hasanuddin. The parameters studied are structure dimensions and wave parameters. Wave parameters consist of wave height (H) and wave period (T), while the structure parameter is the draft structure (D). The result of this study shows that the greater value of both incident wave steepness (Hi/gT2) and structure relative draft (s/d), then the smaller of KEt value will be achieved. Also, the greater relative H/s, the smaller KEt will be achieved. For all cases of study, the transmission coefficient ranges from 0.122 – 0.786.
Analysis of Daylight Distribution on Building Height and Space Depth.
Authors: Jamala Nurul , Wika Annajma Nurul , Kusno Asniawaty
Published: October 2019

Lighting design is one of the priorities in designing buildings. Natural lighting can reduce energy consumption in buildings. Aesthetic levels are the basis of the planning concept, but need to pay attention to the concept of using natural lighting, in order to realize the energy-efficient building design. The purpose of the study was to determine how the level of illuminance affects the opening area, depth of space and height of the building. Quantitative research method is to analysis statistical data from measurements of illuminance levels in space. The results of the study concluded that the level of illuminance in the meeting room of the Center of Technology building in Hasanuddin University exceeded the illuminance standard. The extent of openings in the building envelope affects the illuminance level in space. Natural light distribution affects the height of the building's floor and the depth of space. Based on this conclusion, it is expected that in designing a building it is necessary to pay attention to the building facade, so that the distribution of natural light is not too high into the building and to avoid negative effects such as glare, high brightness and contrast.