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Abstract: A detailed mathematical simulation and experimental investigation of airflow in solar chimneys is studied in this paper. Several experimental studies were carried out on the solar chimney; their choice depends on the parameter of the design and the thermal performances for different geometrical configurations. The experimental tests show that the field speeds in the chimney is influenced by the width of the channel and also of the angle of inclination of the chimney. Therefore, investigations have been carried out in this paper to find the effect of inclination on the performance of solar chimney in Ouargla Province, Algeria. The simulation of this problem is implemented into the commercial CFD code Fluent 6.3. 26. The conservation equations of mass, continuity and energy are solved by the Finite Volume Method. The validation of the results is presented. An good agreement between the experimental results and simulation ones is observed. [Copyright &y& Elsevier]

Abstract: Photovoltaic generators involve many systems operating together. The illumination on a PV generator (PVG) is neither homogeneous nor constant. Some fluctuations in the illumination intensities and spectra, due by example to shadows, with various dynamic, can occur on the PV panels which constitute a big problem for the inverter to determine precisely the position of the Maximum Power Point (MPP) for an optimal and efficient power transfer. So it is very important to analyse the dynamics behaviour of such systems by using electronic simulation tools like ORCAD®, PROTEUS® etc. It is also interesting to consider the possibility to connect PV panels to smart DC/DC converters in order to provide a High DC Voltage (HVDC) bus. The goal of the present paper is to determine very precisely the dynamic response of a PV system with a high global efficiency. In order to easily simulate a global system including PV panel(s) converter(s) and load, with consideration of small partial shading onto the surface, it is advantageous to minimize the number of basic components in the schematics used for the simulation. This allows a better computing convergence on a short simulation time. In the present contribution, a novel global model representing the behaviour of a string, a panel or a PVG in Direct and Inverse biasing modes is studied. Moreover, this model gives a good restitution of a PVG behaviour in case of partial shading. It is also compared with a standard string of photovoltaic cells. The solar-cell model used for this study is a Direct and Reverse Mode (DRM) model, published in previous paper, which integrates the second quadrant corresponding to the reverse operating mode. In partial shading of PV systems the proposed model allows to have a good approximation of the I-V characteristics curves on PV panels with easier an efficient simulation. [Copyright &y& Elsevier]

Abstract: In this paper, direct torque control (DTC) algorithms for double star permanent magnet synchronous machine alimented by two inverters is described. The double star permanent magnet synchronous machine has two sets of three-phase stator windings spatially shifted up by an angle γ=300. The double star permanent magnet synchronous is used in areas of high power industrial applications such as traction and naval propulsion. Because constitute an advantageous choice compared to classical synchronous machine, because of the relatively low torque produced. This machine is controlled by tree level direct torque with speed regulator PI, replaced by the sliding mode regulator to improve the results obtained. The implementation of the DTC multi-level applied to a double star permanent magnet synchronous machine is validated with simulated results. In this paper a method for modeling and simulation of double star permanent magnet synchronous motor drive MATLAB/Simulink. [Copyright &y& Elsevier]

Abstract: The paper presents selected results of a dynamic non-linear model that simulates critical factors in the diffusion of demand-side energy saving equipment. The modelling exercise is customised to the particular characteristics of the Greek islands of the Aegean Sea. Through a sample set of alternative diffusion scenarios, it tests socio-economic and techno-economic system behaviour providing helpful insights in market development and programme design in the wider energy policy debate on effective introduction of new technology. The paper discusses the usefulness of simulation modelling along critical interactions and feedbacks among policy makers (government), the utility operator, consumers and the adopters. [Copyright &y& Elsevier]

Abstract: This paper analysis the cushion performance of the bucket unit for molded pulp material model, which based on the ANSYS software to simulate the compression test and study the effect variety of the draft angle and the height on the model. [Copyright &y& Elsevier]

Abstract: This paper uses Diffuser Augmented Wind Turbine for reference. According to the characteristics of ocean current movement, this paper gives several dome model programs for the straight blade vertical-axis tidal turbine. Make use of it to increase its output power. This paper gives several dome model programs for the straight blade vertical-axis tidal turbine. And optimum scheme is chosen by numerical simulation. [Copyright &y& Elsevier]

Abstract: In order to investigate the typical scale microbial Iron Bacteria of growth properties in circulating cooling water and water quality parameters factors on biofouling formation, this paper is purposed to deal with the slime which was obtained from the cooling tower bottom of circulating water, then a pure strain of Iron Bacteria was obtained through the separation, purification and enrichment culture. According to the morphological observation, as well as the physiological and biochemical indexes identification, the strain was identified as Sphaerotilus. The tubular heat exchanger dynamic simulation was used to study the biofouling formation with Iron Bacteria in circulating cooling water system. The experimental conditions were as follows: the water temperature 30 ± 0.2°C, the flow rate 0.4m / s. This paper selected Iron ion concentration, CODcr, pH value, ORP, temperature and the total number of bacteria as the effect factors of biofouling formation, researching the link between Iron Bacteria, water quality parameters and biofouling formation. The results show that: the existence and content of iron bacteria results in directly increasing of fouling resistance; interacting among the parameters, and together determining the formation of biofouling. [Copyright &y& Elsevier]

Abstract: In view of the defects of the prediction model based on neural network, such as when doing prediction of nonlinear sequence, it is likely to fall into local hypo-strong point, and the rate of training is very slow. This paper presents a fuzzy wavelet neural network (FWNN) approach for annual electricity consumption in high energy consumption city. It is claimed that, due to high fluctuations of energy consumption in high energy consumption cities, conventional regression models do not forecast energy consumption correctly and precisely. Although ANNs have been typically used to forecast short term consumptions, this paper shows that it is a more precise approach to forecast annual electricity consumption. Furthermore, the FWNN approach based on ANN is used to show it can estimate the annual consumption with less error. Actual data from high energy consuming (intensive) from 1983 to 2003 is used to illustrate the applicability of the FWNN approach. This is the first study to present an algorithm based on the ANN and wavelet for forecasting long term electricity consumption in high energy consuming city. The prediction effect of wavelet neural network prediction model is proved in matlab7.0 simulation environment. A better prediction result is gained, and the defect of falling into local hypo-strongpoint is overcome, at the same time, the rate of training is raised compared with the prediction model based on artificial neural network. The calculation result shows that the presented model is effective. [Copyright &y& Elsevier]

Abstract: A new kind of modulation strategy was put forward for on matrix converter (MC), which output voltage in open-loop control can not be adjusted automatically when a disturbance encountered. This paper presents an improved method which adopts the closed-loop control of the output voltage. First of all, the output voltage can be changed into space vector by coordinate transformation. Then, that compared with the target voltage vector to obtain deviation in order to feedback control. Finally, this paper carried out simulation on device modeling, control strategy and voltage closed loop control method using Matlab. Two kinds of interference, typically, are simulated and analyzed in two control ways, and the result shows that the closed-loop control is better than open-loop control, which has a good control effect for input disturbance.Keywords: MC; voltage closed-loop control; equivalent transformation; space vector modulation (SVM); simulation [Copyright &y& Elsevier]

Abstract: This paper proposes a grid-connected cascaded multi-level inverter used in centralized photovoltaic generation. Field programmable gate array (FPGA) is applied to implement the multichannel Carrier Phase Shifting Sinusoidal Pulse Width Modulation(CPS-SPWM) strategy for the inverter. Analysis and practical implementation of the regular sampled three-phase CPS-SPWM waveform has been presented in this paper. An ALRERA FPGA chip is employed to fulfill all the function of modules, such as divider module, triangular carrier generation module, sine wave generation module, comparing module, dead time module and so on. The simulation and experimental results show that the presentation of this grid-connected cascaded multi-level inverter used in the photovoltaic generation system is feasible. [Copyright &y& Elsevier]

Abstract: The paper adopts standard k−ɛ turbulence model and other mathematical models, and completing the blending lignite combustion numerical simulation of 600 MW boiler of one power plant. Three conditions were simulated in this paper, and these three conditions were compared and analyzed, the basic conclusion is consistent with the test. The result shows that the combustion character of blending lignite is lower than burning soft coal. Burning lignite shows a decline furnace temperature, and the simulation results are consistent with the experimental results. Pay attention to adjust the reasonable operating manner, and the operation is safety and economic. At the same time this paper also provides a useful reference for researching tangentially fired boiler furnace process. [Copyright &y& Elsevier]

Abstract: Aiming at the shortcomings appearing in the BP neural network method for obtaining the road surface power spectrum density, the paper applies a new cubic spline weight function neural network (CSWFNN) to the identification of road surface power spectrum density. First, a vibration model with four freedoms is established to simulate the actual vehicles. Subsequently, we deduce the nonlinear relationship between power spectrum density of the response and that of the excitation, and then acquire some input and output data. Next, a CSWFNN is built and trained until converges. In the end, the paper analyses the errors of CSWFNN in the identification of road surface power spectrum density. The results show that the proposed method in the paper successfully overcomes the deficiencies of BP neural network method, and consequently enhances the identification precision of road surface power spectrum density. [Copyright &y& Elsevier]

Abstract: Electronic power is the most widely used energy, and its application degree has been a mark of country development level. This paper introduces a method of voltage fluctuation rate monitor by using virtual instrument technology. Because virtual instrument technology uses computer own hardware and design graphics procedure frame diagram software to complete, which has many advantages of the simple algorithm and fast speed, etc. Through simulating three-phase voltage of electronic power system, this paper completes voltage fluctuation rate monitor of electronic power system and electronic power quality judgment, as well as verifies accuracy of algorithm diagram procedure. [Copyright &y& Elsevier]

Abstract: This paper described the structure of a Shunt Active Power Filter system and compared various methods of active power filter harmonic detection, then the improved adaptive algorithm was used in active power filter harmonic detection; as regards the control strategy, the control method that based on optimal voltage space vector hysteresis current was presented in this paper for tracking control, And by using Matlab/Simulink simulation software, the Adaptive filter detection system and control model of Three-phase three-wire Shunt Active Power Filter were established. Simulation results showed that the selected detection method and control strategy of harmonic current played a fairly good compensation role on the harmonics which was generated by nonlinear loads and had a good dynamic compensation performance. [Copyright &y& Elsevier]

Abstract: It is complicate to process the seismic data from the area below a fault, where there is the pull-up and sag phenomenon in seismic section. And geological processors are difficult to make sure whether the pull-up and sag really exist. So this phenomenon of pull-up and sag makes the fault shadow problem. This paper makes a forward simulation research deeply and presents many different geological models to execute forward numerical simulation. Many common processing flows and migration imaging methods are analyzed and used to overcome the fault shadow problem. At last, this paper concludes one fairly suitable method to resolve the fault shadow problem by comparing the different migration methods. [Copyright &y& Elsevier]

Abstract: Efficient light trapping is essential for silicon thin-film solar cells. Excellent light trapping for silicon thin-film solar cells is achieved with randomly textured superstrates (TCO and/or glass). Due to a continuous and broad variation of occurring structure sizes in such textures, their optical simulation is challenging. In this paper we introduce an approach to establish a methodology for 3D optical simulation of silicon thin-film solar cells on randomly textured superstrates. The approach includes three steps. In a first step a fabricated structure is analysed to identify its typical geometric features. In a second step the single geometrical features are optically simulated using the rigorous coupled wave analysis (RCWA). The third step includes an investigation of how the results of the single features can be combined to describe the optical characteristics of the complete random structure. In this paper we concentrate on the first two steps. We introduce the analysis of an exemplary superstrate structure and investigate the optical properties of the single structure features. Preliminary results of this investigation are shown and a proposition of how to optimise the structure geometry is presented. [Copyright &y& Elsevier]

Abstract: This paper presents a method of calculating an advance angle in order to increase the torque-to-current ratio of a brushless DC (BLDC) motor. The BLDC motor is widely used in various industrial fields because of its high energy density and low maintenance. Because the BLDC motor drives with a square-wave current of electrical 120 degrees duration, the phase current must be commuted every 60 electrical degrees of rotation. Owing to the inductance levels of the motor winding process, the commutation induces a phase lag and deviations from the ideal square-wave current form. These non-ideal characteristics reduce the torque-to-current ratio. Advancing the commutation timing can improve the torque-to-current ratio. This paper analyzes the torque performances of the BLDC motor and proposes a method of calculating the advance angle in order to improve the torque-to-current ratio. The simulation results of a 20W, 20,000rpm BLDC motor verify the effectiveness of the proposed calculation method. [Copyright &y& Elsevier]

Abstract: A large AC generator is an important component of the power system. Researches on the AC generator relaying for the next-generation ECMS and an efficient operation of protection control system are necessary. These require developments on detailed generator modeling and internal fault analysis, and prototyping for multifunctional IED device dedicated to next-generation production. In this paper, over-excitation relaying algorithm is one of the main protection elements which have an important role in DGPS(Digital Generator Protection System), was proposed. This paper first briefly introduces a principles of over-excitation and DFT-based gain compensation algorithm was adopted for the frequency measurement. Subsequently, protection scheme of over-excitation was presented. The 765[kV] modeling data of South Korea using EMTP-RV was used for simulations. The simulation result of over-excitation relaying are also provided. [Copyright &y& Elsevier]

Abstract: The higher power microwave heating source, in the industrial and engineering needs, is obtained through inputting microwave energy of multi-open feed into cavity via near-field radiation, resulting in the coupling of each feed. Meanwhile, the initial situation, the ratio of fluid and the permittivity are highly nonlinear in the process of microwave heating during technical operation process by microwave heating process cycling fluid medium. This paper is presented an improved Anti-predatory Particle Swarm Optimization (APSO) algorithm to optimize the three parameters of PID controller, and is applied to control the complicated and coupling of microwave heating. It is shown through intelligent calculation and simulation experiments that the improved APSO has good performance. And this paper provides an alternative for control of multi-couple and uncertain objects in industry. [Copyright &y& Elsevier]

Abstract: This paper presents an efficient algorithm for multi-objective distribution feeder reconfiguration based on Modified Honey Bee Mating Optimization (MHBMO) approach. The main objective of the Distribution feeder reconfiguration (DFR) is to minimize the real power loss, deviation of the nodes’ voltage. Because of the fact that the objectives are different and no commensurable, it is difficult to solve the problem by conventional approaches that may optimize a single objective. So the metahuristic algorithm has been applied to this problem. This paper describes the full algorithm to Objective functions paid, The results of simulations on a 32 bus distribution system is given and shown high accuracy and optimize the proposed algorithm in power loss minimization. [Copyright &y& Elsevier]