The study presents a new out-of-step algorithm used for the protection of synchronous generators. The algorithm is implemented on the principle of a digital phase comparison in the time domain. Phase ...voltages and currents measured at the generator bus bars are used as input signals. On the basis of the measured phase voltages and currents and known generator parameters, the internal voltages of the generator in the time domain are calculated. The algorithm compares the phase and internal voltages of synchronous generator and on the basis of the out-of-step index it detects a disturbance. Model of the test network is implemented in MATLAB/Simulink software package. The algorithm was tested on turbo and hydro-generator models. The proposed algorithm test results were compared with a conventional method based on measurement of the impedance. The obtained results show good properties of the proposed algorithm.
This paper describes the system activity and the importance of autonomous inertial navigation system /INS/ and its implementation to control the robotic arm. The article further introduces the ...execution of DC motor regulation utilized for the positioning of a rotary positioned arm. The motor control comprises the current regulation, angular velocity and the rotation of the motor shaft fixed to the arm regarding the required angular change course of the arm rotation. The regulation structure of the DC motor is carried out in MATLAB/Simulink programme. The arm movement is investigated via mathematical model and virtual dynamic model formed in MSC ADAMS programme.
The proton exchange membrane fuel cell (PEMFC) is the fastest growing fuel cell technology on the market. Due to their sustainable nature, PEMFCs are widely adopted as a renewable energy resource. ...Fabricating a PEMFC is a costly process; hence, mathematical modeling and simulations are necessary in order to fully optimize its performance. Alongside this, the feasibility of a waste heat recovery system based on the organic Rankine cycle is also studied and power generation for different operating conditions is presented. The fuel cell produces a power output of 1198 W at a current of 24A. It has 50% efficiency and hence produces an equal amount of waste heat. That waste heat is used to drive an organic Rankine cycle (ORC), which in turn produces an additional 428 W of power at 35% efficiency. The total extracted power hence stands at 1626 W. MATLAB/Simulink R2016a is used for modeling both the fuel cell and the organic Rankine cycle.
This project designs a smart glove, which can be used for motion tracking in real time to a 3D virtual robotic arm in a PC. The glove is low cost with the price of less than 100 € and uses only ...internal measurement unit for students to develop their projects on augmented and virtual reality applications. Movement data from the glove is transferred to the PC via UART DMA. The data is set as the motion reference path for the 3D virtual robotic arm to follow. APID feedback controller controls the 3D virtual robot to track exactly the haptic glove movement with zero error in real time. This glove can be used also for remote control, tele-robotics and tele-operation systems.
In a polymer electrolyte membrane fuel cell, managing the water content is crucial in determining the fuel cell's performance stability. The micro-porous layer is located at the interface between ...catalyst layer and gas diffusion layer of PEMFC. Water transport in fuel cell is improved on using micro-porous layer. This paper outlines a two-phase model for proton exchange membrane fuel cells with micro-porous layer. The model is one-dimensional, steady-state and non-isothermal. Membrane water transport is given significant attention in the modeling process. The suggested one-dimensional model predicts the influence of current density and water transport in PEMFC realistically well. Modeling is done using MATLAB/SIMULINK and the predictions are compared to the experimental performance characteristics of fuel cell. We have devised an easy to implement model which forecasts the most appropriate parameter operating ranges. The potential and flux profiles, water content inside the fuel cell are also plotted and analyzed.
Digital measuring elements in microprocessor protections of electrical installations are implemented mainly with the use of orthogonal components of input signals. To form orthogonal components in ...microprocessor protections, digital Fourier filters are most widely used, the action of which is al-ways inertial in transient modes. As a result, a dynamic error appears, changing over time and completely disappearing when a steady-state regime occurs. The dynamic error consists of amplitude and phase errors, which can significantly affect the functioning of digital measuring elements and create conditions for their excessive triggering during external short circuits and deceleration of triggering during internal short circuits. Therefore, it is advisable to compensate for the dynamic error, for which it is proposed to determine the amplitude and phase of the fundamental harmonic signal by specially formed orthogonal components. The proposed method of forming orthogonal components of the signal with compensation of dynamic amplitude and phase errors is based on the use of orthogonal components of the digital Fourier filter, followed by the determination of their samples of the final orthogonal components that coincide with the orthogonal components of Fourier in steady-state mode and shifted in phase relative to the latter in transient mode. The amplitude and phase of the signal with minimal dynamic phase errors are calculated from the samples of the final orthogonal components in the digital measuring element. In the dynamic modeling environment of MATLAB-Simulink-SimPowerSystems, a digital model is implemented, which includes a power system, a three-phase group of current transformers, a load, a short-circuit block, as well as a model of a digital measuring element implemented on the basis of the final orthogonal components. The operation of the digital model was checked using two types of test effects, viz. a sinusoidal signal with a frequency of 50 Hz, and a signal close to the real secondary current of a short-circuit current transformer. As a result of the calculations, it was found that digital measuring elements made on the basis of the proposed methodology made it possible to reduce the relative dynamic amplitude and phase errors by three to four times, as compared with the Fourier measuring element taken as a reference.
Reliable and safe operation of electric motors in the industry is highly desirable. Accurate modelling is the first step in developing a diagnostic tool for different types of failures. This study ...presents a generalised dq-model for interior-mount line start permanent magnet synchronous motors under asymmetrical stator phase's windings. The presented dq-model has been derived using winding theorem. Implementation and simulation of the derived dq-model has been done using MATLAB/SIMULINK software. For validation purposes, interior-mount line start permanent magnet synchronous motor (LSPMSM) under this fault condition is implemented using the JMAGTM-finite-element-based software. The performance of a 1-hp interior-mount LSPMSM motor under different loading levels and stator winding asymmetric conditions has been investigated using the simulated MATLAB and JMAG models. Simulation results of MATLAB and JMAG are in very good agreement and show that under asymmetrical stator winding condition, oscillations are obvious in the torque characteristics of the motor. In addition, the torque experience high oscillations at a steady state due to the asymmetry between stator phases. Finally, investigating torque frequency spectrum showed that they can be good signatures in diagnosing asymmetrical stator winding faults in interior-mount LSPMSM.
The performance of Silicon solar cells is effected by the presence of cracks which are inevitable. These cracks exist in different patterns in the cells. Any given particular pattern of cracks leads ...to formation of recombination centers and insulated areas. Furthermore, these crack patterns lead to the formation of hot spots leading to the temperature increase and failure of performance of solar cells. In this study, the failure of performance of solar module is analyzed considering different crack patterns leading to different amount of areas of insulation. However, this particular percentage of insulated area is correlated with the percentage of shaded area in the module due to obstruction of sun light falling on the cells. The performance of Silicon solar cells is implemented through a specialized lens known as the single-diode model. The impact of cracks is examined in terms of partial shading conditions and plots that unveil the power-voltage and current–voltage characteristics of the PV panels across various conditions are constructed using MATLAB/Simulink.
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