Modeling of PV systems is very crucial for embedded power system applications and maximum power point tracking. This paper presents a proposed two-diode model for PV module with its seven-parameter ...capable of analytically describing I–V characteristic for each generic condition of operative temperature and solar irradiance. Determination of seven-parameter plays an important role in a PV module fabrication, design and an accurate prediction of PV system performance at low and high irradiance levels. Seven-parameter is estimated using the Newton Raphson method with the aid of initial values which are derived from basic equations of the model and manufacturing data sheet at standard test conditions. Newton Raphson and Runge–Kutta Merson iteration methods are proposed to verify the capability of the model to fit non-linear output characteristics of I–V and P–V. The procedures were tested on three different modules of multi-crystalline, amorphous, and thin film solar cell PV manufacturers. Results are compared with the points taken directly from the manufacturer׳s published curves and the proposed results of other authors. The results of proposed model show an excellent agreement with respect to data sheet and other works.
•Two diode model for PV module with its seven-parameter.•Seven-parameter is estimated by using the Newton Raphson method.•Results show an excellent correspondence to the model.•Provides a clear and accurate representation of the I–V and P–V characteristics PV.
The conventional algorithm of perturb and observe (P&O) is widely applied due to its simplicity, low cost and easy implementation. However, it suffers from instabilities during rapid changes of ...weather and/or oscillation around maximum power point (MPP) at steady state. Instabilities occur due to the incorrect decision taken by the conventional P&O algorithm at the first step change in duty cycle during the rapid change in radiation. The reason for the steady-state oscillation is the continuous perturbation and tradeoff between step sizes and the convergence time. This study presents a modified P&O algorithm to overcome such drawbacks. It uses a constant load technique to help the conventional P&O algorithm for recognising the cause of power change and to enable it in taking the right decision at first step change in duty cycle during rapid change of weather. The proposed algorithm is simulated using a single solar photovoltaic module of 80 W and a DC/DC boost converter. It is validated experimentally and implemented within an embedded microcontroller. The experimental setup presents a proposed model-based design methodology that uses measurements’ data for MPP tracking systems’ design. It combines hardware-in-the-loop simulation and prototype testing using actual weather measurements. Simulation and experiments show excellent results.
The accurate models of photovoltaic systems are the core of solar energy studies that are describing the system performance and behavior under different operating conditions. The improving of ...photovoltaic models based on optimizing method is recently the main simulation tool to construct I-V and P–V characteristic curves with the aid of system parameters. These parameters are extracted by using powerful optimal techniques that are building-up from datasheet of manufacturers or experimental data. This paper presents a novel proposed photovoltaic model based on Marine Predators Algorithm to estimate the optimal model parameters of solar cells or modules. Also, it can extract parameters of single diode, double diode and three diode models. Moreover, the Route Mean Square Error value between each model computed parameters and measured results of photovoltaic components are considered as the objective function. R.T.C. France Solar Cell, Photowatt-PWP201 and thin-film photovoltaic modules have been implemented to extract parameters for all three previously mentioned models at different irradiance intensities or temperature degrees. The proposed algorithm results of such cells and modules for each diode model are compared with other research works and manufacturer's results. Moreover, the evaluation of proposed algorithm has been presented considering the complexity analysis and statistical tests. The compared results show that, the accuracy of algorithm results is the best and their I-V and P–V characteristic curves are highly coinciding with manufacturer's curves. Therefore, the results of the proposed algorithm are satisfied with high superiority and better reliability to optimize parameters under different operating conditions.
In this paper, a robust speed control scheme for high dynamic performance sensorless induction motor drives based on the H_infinity (H∞) theory has been presented and analyzed. The proposed ...controller is robust against system parameter variations and achieves good dynamic performance. In addition, it rejects disturbances well and can minimize system noise. The H∞ controller design has a standard form that emphasizes the selection of the weighting functions that achieve the robustness and performance goals of motor drives in a wide range of operating conditions. Moreover, for eliminating the speed encoder—which increases the cost and decreases the overall system reliability—a motor speed estimation using a Model Reference Adaptive System (MRAS) is included. The estimated speed of the motor is used as a control signal in a sensor-free field-oriented control mechanism for induction motor drives. To explore the effectiveness of the suggested robust control scheme, the performance of the control scheme with the proposed controllers at different operating conditions such as a sudden change of the speed command/load torque disturbance is compared with that when using a classical controller. Experimental and simulation results demonstrate that the presented control scheme with the H∞ controller and MRAS speed estimator has a reasonable estimated motor speed accuracy and a good dynamic performance.
The electro-chemical proton exchange membrane fuel cell (PEMFC) is an inventing electrical generator from chemical reaction process as a green energy source. An accurate PEMFC model with its precise ...parameters should be used to carefully fitting of polarization curve to best study and design of its characteristics and performance. This paper introduces an accurate PEMFC model based on recent metaheuristics algorithms to evaluate precisely the unknown parameters of PEMFC. Algorithms of; Whale Optimization Algorithm (WOA) , Weighted Differential Evolution Algorithm (WDE) , Differential evolution algorithm with strategy adaptation (SADE) , Moth- Flame Optimization Algorithm (MFO) , adaptive differential evolution with optional external archive (JADE), Improved mine blast algorithm (IMBA), Gray Wolf Optimizer (GWO), Dragonfly algorithm (DA), Differential EVOLUTION ALGORITHM (DE) , Cumulative Population Distribution Information in Differential Evolution (CPIJDE) , Differential evolution based on covariance matrix learning (COBIDE) , Covariance Matrix Adaptation Evolution Strategy (CMA-ES) , Bernstain-search differential evolution algorithm (BSD), Backtracking Search Optimization Algorithm (BSA) , Bezier Search Differential Evolution Algorithm (BESD ) , DIFFERENTIAL SEARCH ALGORITHM (DSA) and Bijective DSA (B-DSA) , Biogeography-based optimization (BBO); have been applied to estimate model of PEMFC. The verification of the suggested optimizing algorithms is applied on three practical PEMFC stacks of BCS 500-W PEM, 500 W SR-12PEM and 250 W stacks, for different operating conditions. The accuracies of the PEMFC extracted parameters are measured in sum of square errors (SSE) between the results obtained by the optimizing parameters and the test results of the fuel cell stacks in the objective function. Also, the applied methods have been validated as compared results with different research works that were listed in literatures. Moreover, the polarization curves of the applied methods are clear and coinciding with manufacturing polarization curves for all the case study results. So, the suggested PEMFC optimizing model has superiority on the comparative models with respect to the system accuracy and convergence process.
•Focusing on the optimizing proton exchange membrane fuel cells (PEMFCs) model parameters.•A wide review of various PEMFC models based on variety different algorithms.•Different optimization techniques have been discussed from view of their merits, de-merits, suitability.•Parameters of PEMFC model have been estimated using recent metaheuristics algorithms.•The optimization algorithms have been elaborated to solve the considered optimization problem.•A comprehensive comparison among the results of the applied optimization algorithms have been presented.
Recent hybrid simulators (or co-simulators) of the electric power system are focused on scientific and research features to propose and develop novel and more accurate simulators. The present paper ...demonstrates one more hybrid modelling approach based on application and combination of three modeling approaches all together: physical, analog and digital. The primary focus of the proposed approach is to develop the simulation tool ensuring such vital characteristics as three-phase simulation and modeling of a single spectrum of processes in electric power system, without separation of the electromagnetic and electromechanical transient stages. Moreover, unlimited scalability of the electric power system model and real-time simulation to ensure the opportunity of data exchange with external devices have been considered. The description of the development of the hybrid model of back-to-back HVDC link based on the proposed approach is discussed and analyzed. To confirm properties of the mentioned hybrid simulation approach and hybrid model of back-to-back HVDC link, the simulation results of the interconnection of non-synchronously operating parts of the electric power system; power flow regulation; dynamic response to external fault and damping of power oscillation in electric power system are presented and examined. Moreover, to confirm the adequacy of the obtained results, the comparison with a detailed voltage source converter HVDC model (Simulink Matlab) and Eurostag software are introduced.
Optimal planning of integration the Photovoltage Distributed Generation (PV-DG) and DSTATCOM is a crucial task due to the stochastic variations of PV output power and the load demand which are ...related to solar irradiance variations and the activities of the customers, respectively. In this article, the optimal planning problem of the PV-DG and DSTATCOM system is solved. The proposed model considers the uncertainties of the solar irradiance and the load demand for a multi-objective function, including the cost reduction, the voltage profile, and stability index improvement. Modified Ant Lion Optimizer (MALO) is proposed to enhance the basic ALO searching ability using two strategies. The first strategy is based on Levy Flight Distribution (LFD) to strengthen the exploration of the algorithm and avoid the premature of the basic ALO. In contrast, the second strategy is based on updating the solutions in a spiral orientation to improve the exploitation of the algorithm. The IEEE 69-bus and 118-bus radial distribution systems are used to demonstrate the effectiveness of the proposed method, and the yielded simulations are compared with the basic ALO and other well-known optimization techniques for power loss minimization under deterministic conditions. The simulation results demonstrate that the techno-economic benefits can be increased considerably by optimal inclusion of two PV-DGs and DSTATCOMs compared with a single system.
Variation of solar irradiances on the value of seven parameters of two-diode model plays an important role in a photovoltaic (PV) modules performance to develop design and fabrication of PV modules. ...This paper proposes a novel modeling approach for amorphous silicon thin film PV module to determine the effect of solar irradiance change on seven parameters of two-diode model and to describe the I-V characteristic curves for each generic condition of operative solar irradiance. The proposed model is based on the rate change of seven parameters with respect to irradiance change. The rate change of seven parameters is derived from current equation of two-diode model at maximum power point (MPP) of different solar irradiance levels. The values of the parameters of the two-diode model are extracted with respect to different solar irradiance levels using precise Runge-Kutta-Merson iterative method. To validate the capability of the new proposed method, the new proposed method is verified on three different amorphous silicon and thin film PV modules, U-EA110, MPV95-S, and MST-43LV, for various I-V and P-V manufacturer curves. Results are compared with the data issued by different manufacturers. The I-V and P-V curves of manufacturing three different amorphous and thin film PV modules have a good agreement as compared with computed results of proposed model.
The electrical demand is quickly increased, and renewable energy sources are an indispensable need for supporting the electric grid and supplying the isolated loads. Renewable energy is found in ...numerous forms like solar energy, wind energy, tidal energy. Solar power system is clean, and large amounts of solar radiation arrive to the surface of the earth. This paper aims to maximize the amount of extracted electrical power from the solar energy system. This work investigates in detail the concept of MPPT techniques which significantly increase the efficiency of the solar PV system. This paper presents a simulation-based comparative study between two most common algorithms, perturb and observe and incremental conductance techniques, to optimize the energy conversion efficiency of PV system. Simulation analysis and results of the PV module are made to get its characteristics.
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