The relevance of the study is due to the need to improve and expand the possibilities of calculating electrical circuits in transients. As an object for research, linear electric circuits of the ...second and higher order with zero initial conditions are considered. The main goal of the research is the task of performing dynamic calculations when simulating transients in linear high-order circuits by the methods of structural simulation in the Matlab Simulink software environment. The main attention is paid to the issues of constructing structural diagrams of high-order electric circuit models. The basis for the description of processes is the equation, compiled according to the laws of Kirchhoff, linking the instantaneous values of currents and voltages of the elements of the electric circuit through their parameters. Examples of numerical modelling using variants of models of structural circuits of the electric circuit are given. The advantages of the method of simulation structural modelling in the calculation of dynamic circuits with respect to existing analytical methods for calculating transients in high-order circuits are also considered in this paper.
•A new approach for the cost-optimal study of building energy performance is shown.•A multi-objective optimization of energy demand and thermal comfort is considered.•EnergyPlus and MatLab are ...combined interactively. A genetic algorithm is used.•After the description of the method, this has been applied to an Italian case study.•The cost-optimal package of energy renovations is found for an existing building.
The recast version of the Energy Performance of Buildings Directive (2010/31/EU) proposes a comparative methodology aimed at defining the energy performance of buildings “with a view to achieving cost-optimal levels”. Really, how can the cost-optimal technologies be detected? Moreover, how can the most proper packages of energy efficiency measures be chosen in order to obtain the cost-optimality? This paper would provide answers to these questions, by proposing a new methodology for the evaluation of the cost-optimality, by means of the multi-objective optimization of energy performance of buildings and indoor thermal comfort. The optimization procedure is developed by means of the coupling between MatLab and EnergyPlus, by implementing a genetic algorithm, and it allows the evaluation of profitable and feasible packages of energy efficiency measures applied to buildings. Then, following the adoption of these packages, the global cost over the lifecycle of the building is calculated, in order to identify the cost-optimal solution. After the presentation of the methodology, the developed method is proposed for the optimization of the energy retrofit of an existing building. Furthermore, the method can be applied also for new architectures, by considering reference buildings.
•The proposed method is simple, inexpensive and suitable for small PV systems.•The photodiodes are useful to detect partial shading and irradiance changes.•Whole-year MPPT simulations have been ...conducted to evaluate every method.•The PV model can calculate the output curves under complex shading patterns.•The proposed method overcomes the standard ones regardless the climatic conditions.
Maximum Power Point Tracking (MPPT) is needed in a photovoltaic system to ensure the operation in the Maximum Power Point (MPP), maximizing the generated energy. Many MPPT techniques have been developed. Perturbation and observation, as well as incremental conductance, are by far the most widely used because of their simplicity. However, they have some weak points and problems that affect their efficiency, especially under rapid irradiance changes and partial shading. This paper proposes a novel MPPT method which can be implemented in PV (photovoltaic) inverters and charge controllers. The most innovative feature is the presence of photodiodes as irradiance sensors. Thanks to irradiance measurement, the proposed method can recognize problematic scenarios and execute specific algorithms to prevent malfunction under these situations. The MPPT method has been theoretically analyzed; efficiency results are shown in comparison with standard techniques, which verify its feasibility.
Abstract
Currently, the discussion on the modeling method characterized by the small electrodynamic shakers, especially the mathematic analytical method, is relatively sparse. In this paper, taking ...BK4809 as an example, a modeling method for small shakers based on analytical formulations is discussed. The detailed mathematical analysis and derivation process for the small shakers are performed, and the corresponding modeling formulations are concluded; then, the simulation tests are carried out in MATLAB. Through comparison with the reference data, the validation tests show that based on analytic formulations combined with the MATLAB built-in system identification functions, the results of modeling methods match well with the experiment data, and the concluded method is effective.
A new algorithm for the solution of multimaterial topology optimization problems is introduced in the present study. The presented method is based on the splitting of a multiphase topology ...optimization problem into a series of binary phase topology optimization sub-problems which are solved partially, in a sequential manner, using a traditional binary phase topology optimization solver; internal solver. The coupling between these incomplete solutions is ensured using an outer iteration strategy based on the block coordinate descend method. The presented algorithm provides a general framework to extend the traditional binary phase topology optimization solvers for the solution of multiphase topology optimization problems. Interesting features of the presented algorithm are:generality, simplicity and the ease of implementation. The presented algorithm is used to solve multimaterial minimum structural and thermal compliance topology optimization problems based on the classical optimality criteria method. Details of MATLAB implementation are presented and the complete program listings are provided as the Supplementary Materials. The success and performance of the presented method are studied through several two dimensional numerical examples.
Abstract
The Denavit-Hardenberg (D-H) method is widely used to calculate the kinematic properties of various types of robots, where it is possible to obtain a complete description of the robot’s ...operation. Based on this method’s parameters, it is possible to provide the typical arrangement of all robotic joints. In this work, the kinematic properties such as displacement, velocity, and acceleration of a 3DOF Planar Robot are analyzed using MATLAB software. Two types of paths are traced in this paper, the straight path, and the zigzag path.
This report presents experimental results derived from a Proton Exchange Membrane fuel cell with a serpentine flow plate design. The investigation seeks to explore the effects of some parameters like ...cell operational temperature, humidification and atmospheric pressure on the general performance and efficiency of PEM fuel cell using MATLAB. A number of codes were written to generate the polarization curve for a single stack and five (5) cell stack fuel cell at various operating conditions. Detailed information of hydrogen and oxygen consumption and the effect they have on the fuel cell performance were critically analysed. The investigation concluded that the open circuit voltage generated was less than the theoretical voltage predicted in the literature. It was also noticed that an increase in current or current density reduced the voltage derived from the fuel cell stack. The experiment also clearly confirmed that when more current is being drawn from the fuel cell, more water will also be generated at the cathode section of the cell hence the need for an effective water management to improve the performance of the fuel cell. Other parameters like the stack efficiency and power density were also analysed using the experimental results obtained.
•The work presents experimental results from a PEM fuel cell with a serpentine flow plate design.•It explores the effect of cell temperature, humidification and pressure on its efficiency.•The presence of excess oxygen with respect to hydrogen improved the fuel cell performance.•The operating temperature is a key factor in determining the fuel cell efficiency.
Based on the scientific visualization function of MATLAB, the computer simulation of optical experimental phenomena has obvious effect in the application of experimental teaching, which improves the ...measurement accuracy of the experiment, expands the measurement range and intuitively analyzes the influence of the changes of various parameters on the experimental results. In this paper, based on the theory of wave optics, the simulation of Young’s double slit interference is realized by using Matlab’s powerful matrix operation function and graphics drawing function. The simulation image is in good agreement with the experimental results.
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