scholarly journals Numerical approach for extraction of photovoltaic generator single-diode model parameters

2021 ◽  
Vol 2 (2) ◽  
pp. 58-66
Author(s):  
Abdelaaziz Benahmida ◽  
Noureddine Maouhoub ◽  
Hassan Sahsah
Keyword(s):  
Ideality Factor ◽  
Series Resistance ◽  
Least Square Method ◽  
Numerical Approach ◽  
Least Square ◽  
Physical Parameters ◽  
Model Parameters ◽  
Shunt Resistance ◽  
Key Points ◽  
Photovoltaic Generators

In this work, a numerical approach has been proposed to estimate the five single-diode circuit model physical parameters of photovoltaic generators from their experimental current-voltage characteristics. Linear least square method has been used to solve the system of three linear equations to express the shunt resistance, the saturation current and the photocurrent as a function of the series resistance and the ideality factor. Two key points have been used to solve the system of two nonlinear equations to extract values of series resistance and ideality factor. The advantage of the proposed method with respect of existing numerical techniques is that use only two key points of the experimental characteristic and need only two initial guesses and does not use any approximation. To evaluate the proposed method, three PV generators data have been used to compare the experimental and the theoretical curves. The application of the proposed method provides a good agreement with the experimental.

scholarly journals Optimization of accurate estimation of single diode solar photovoltaic parameters and extraction of maximum power point under different conditions

2021 ◽  
pp. 46-53
Author(s):  
F. Akbar ◽  
T. Mehmood ◽  
K. Sadiq ◽  
M.F. Ullah
Keyword(s):  
Series Resistance ◽  
Least Square Method ◽  
Least Square ◽  
Flower Pollination Algorithm ◽  
Solar Photovoltaic ◽  
Saturation Current ◽  
Unknown Parameters ◽  
Shunt Resistance ◽  
Flower Pollination ◽  
Diode Ideality Factor

Introduction. With the snowballing requirement of renewable resources of energy, solar energy has been an area of key concern to the increasing demand for electricity. Solar photovoltaic has gotten a considerable amount of consideration from researchers in recent years. Purpose. For generating nearly realistic curves for the solar cell model it is needed to estimate unknown parameters with utmost precision. The five unknown parameters include diode-ideality factor, shunt-resistance, photon-current, diode dark saturation current, and series-resistance. Novelty. The proposed research method hybridizes flower pollination algorithm with least square method to better estimate the unknown parameters, and produce more realistic curves. Methodology. The proposed method shows many promising results that are more realistic in nature, as compared to other methods. Shunt-resistance and series-resistance are considered and diode constant is not neglected in this approach that previously has been in practice. The values of series-resistance and diode-ideality factor are found using flower pollination algorithm while shunt-resistance, diode dark saturation current and photon-current are found through least square method. Results. The combination of these techniques has achieved better results compared to other techniques. The simulation studies are carried on MATLAB/Simulink.

scholarly journals Simulations Based on Experimental Data of the Behaviour of a Monocrystalline Silicon Photovoltaic Module

2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
Abraham Dandoussou ◽  
Martin Kamta ◽  
Laurent Bitjoka ◽  
Patrice Wira ◽  
Alexis Kuitché
Keyword(s):  
Experimental Data ◽  
Ideality Factor ◽  
Extraction Method ◽  
Series Resistance ◽  
Least Square Method ◽  
Monocrystalline Silicon ◽  
Least Square ◽  
Photovoltaic Module ◽  
Saturation Current ◽  
Reverse Saturation Current

The performance of monocrystalline silicon cells depends widely on the parameters like the series and shunt resistances, the diode reverse saturation current, and the ideality factor. Many authors consider these parameters as constant while others determine their values based on the I-V characteristic when the module is under illumination or in the dark. This paper presents a new method for extracting the series resistance, the diode reverse saturation current, and the ideality factor. The proposed extraction method using the least square method is based on the fitting of experimental data recorded in 2014 in Ngaoundere, Cameroon. The results show that the ideality factor can be considered as constant and equal to 1.2 for the monocrystalline silicon module. The diode reverse saturation current depends only on the temperature. And the series resistance decreases when the irradiance increases. The extracted values of these parameters contribute to the best modeling of a photovoltaic module which can help in the accurate extraction of the maximum power.

scholarly journals The Parameter Estimation of Double Exponential Pulse Based on a Least Infinity Norm Fitting Method

2021 ◽  
Vol 2083 (4) ◽  
pp. 042002
Author(s):  
Yuewu Shi ◽  
Wei Wang ◽  
Zhizhen Zhu ◽  
Xin Nie
Keyword(s):  
Estimation Error ◽  
Estimation Method ◽  
Maximum Amplitude ◽  
Least Square Method ◽  
Least Square ◽  
Physical Parameters ◽  
Infinity Norm ◽  
Fitting Method ◽  
Double Exponential ◽  
Exponential Pulse

Abstract This paper presents an estimation method of double exponential pulse (DEP) between the physical parameters rise time (t r), full width at half maximum amplitude (t FWHM) and the mathematical parameters α, β. A newly fitting method based on the least infinity norm criterion is proposed to deal with the estimation problem of DEP. The calculation process and equation of parameters of this method is proposed based on an m-th-order polynomial fitting model. This estimation method is compared with the least square method by the same data and fitting function. The results show that the maximum estimation error of parameters of double exponential pulse obtained by the least infinity norm method is 1.5 %.

Cutting Force Empirical Model of High-Speed Precision Hard Cutting GCr15

2009 ◽  
Vol 69-70 ◽  
pp. 301-305
Author(s):  
Jing Shu Hu ◽  
Yuan Sheng Zhai ◽  
Fu Gang Yan ◽  
Yu Fu Li ◽  
Xian Li Liu
Keyword(s):  
Cutting Force ◽  
Empirical Model ◽  
High Speed ◽  
Orthogonal Design ◽  
Cutting Speed ◽  
Least Square Method ◽  
Cutting Parameters ◽  
Least Square ◽  
Physical Parameters ◽  
Hard Cutting

In the cutting process, cutting force is one of the important physical parameters, which affects the generation of cutting heat, tool life and surface precision of workpiece directly. In this paper an orthogonal design of experiment and subsequent data is analyzed using high speed finish hard cutting GCr15 whose hardness is 65HRC. Cutting speed is 200-400m/min, to study the influence of cutting parameters on cutting force, cutting force empirical model has obtained from least square method.

Examination of Correlation Between Arousal Level and Auditory Environmental Change Using Rock and Classic Music

2017 ◽  
Author(s):  
Kentaro Miyago ◽  
Kenyu Uehara ◽  
Takashi Saito
Keyword(s):  
Visual Cortex ◽  
Frontal Lobe ◽  
Traffic Accidents ◽  
Evaluation Method ◽  
Duffing Oscillator ◽  
Least Square Method ◽  
Arousal Level ◽  
Least Square ◽  
Model Parameters ◽  
Eeg Data

Recently, traffic accidents due to drowsy driving, operation mistake in the power plant by drowsiness and decrease arousal in employment during work have been attracted as problems. To avoid such an accident, arousal level could be quantitatively evaluated in real time. We suggested that the one of the parameters of Duffing oscillator parameters is related to the conventional arousal level using the EEG frequency component. However, in this examination, effects on the EEG from visual and active behavior were considered, but those from hearing also need to be investigated. In this paper, we performed the experiment in the musical environment using rock and classic music to investigate the model parameters for effect of the auditory stimulation, and acquired EEG data in Visual cortex and Frontal lobe. The acquired EEG data was used to identify the model parameters, which were identified solving the inverse problem by Least Square method. Results of investigating correlation between conventional arousal revel and model parameter shows a significant correlation in case of the auditory environmental situation. Moreover, Visual cortex is better than Frontal lobe as a measurement point in this evaluation method.

scholarly journals Online Parameter Identification and State of Charge Estimation of Battery Based on Multitimescale Adaptive Double Kalman Filter Algorithm

2020 ◽  
Vol 2020 ◽  
pp. 1-20
Author(s):  
Wenxian Duan ◽  
Chuanxue Song ◽  
Yuan Chen ◽  
Feng Xiao ◽  
Silun Peng ◽  
...  
Keyword(s):  
Kalman Filter ◽  
Parameter Identification ◽  
Unscented Kalman Filter ◽  
Least Square Method ◽  
State Of Charge ◽  
Least Square ◽  
Accurate Estimation ◽  
Battery Life ◽  
Model Parameters ◽  
Simulation Results

An accurate state of charge (SOC) can provide effective judgment for the BMS, which is conducive for prolonging battery life and protecting the working state of the entire battery pack. In this study, the first-order RC battery model is used as the research object and two parameter identification methods based on the least square method (RLS) are analyzed and discussed in detail. The simulation results show that the model parameters identified under the Federal Urban Driving Schedule (HPPC) condition are not suitable for the Federal Urban Driving Schedule (FUDS) condition. The parameters of the model are not universal through the HPPC condition. A multitimescale prediction model is also proposed to estimate the SOC of the battery. That is, the extended Kalman filter (EKF) is adopted to update the model parameters and the adaptive unscented Kalman filter (AUKF) is used to predict the battery SOC. The experimental results at different temperatures show that the EKF-AUKF method is superior to other methods. The algorithm is simulated and verified under different initial SOC errors. In the whole FUDS operating condition, the RSME of the SOC is within 1%, and that of the voltage is within 0.01 V. It indicates that the proposed algorithm can obtain accurate estimation results and has strong robustness. Moreover, the simulation results after adding noise errors to the current and voltage values reveal that the algorithm can eliminate the sensor accuracy effect to a certain extent.

scholarly journals Grey power models based on optimization of initial condition and model parameters

2014 ◽  
Vol 4 (2) ◽  
pp. 370-382 ◽  
Author(s):  
Yunchol Jong ◽  
Sifeng Liu
Keyword(s):  
Least Square Method ◽  
Least Square ◽  
Model Parameters ◽  
Initial Condition ◽  
Content Type ◽  
Novel Approach ◽  
New Information ◽  
Power Models ◽  
Grey Verhulst Model ◽  
Verhulst Model

Purpose – The purpose of this paper is to propose a novel approach to improve prediction accuracy of grey power models including GM(1, 1) and grey Verhulst model. Design/methodology/approach – The modified new models are proposed by optimizing the initial condition and model parameters. The new initial condition consists of the first item and the last item of a sequence generated by applying the first-order accumulative generation operator on the sequence of raw data. Findings – It is shown that the newly modified grey power model is an extension of the previous optimized GM(1, 1) and grey Verhulst model. And the optimized initial condition reflected the principle of new information priority. Practical implications – The result of a numerical example indicates that the modified grey model presented in this paper with better prediction performance. Originality/value – The new initial condition are derived by weighted combination of the first item and the last item. The coefficients of weight obtained by the least square method.

MHD nanofluid flow analysis in divergent and convergent channels using WRMs and numerical method

2014 ◽  
Vol 24 (5) ◽  
pp. 1191-1203 ◽  
Author(s):  
M. Hatami ◽  
D.D. Ganji
Keyword(s):  
Numerical Method ◽  
Analytical Methods ◽  
Flow Analysis ◽  
Least Square Method ◽  
Numerical Approach ◽  
Least Square ◽  
Science And Engineering ◽  
Nanofluid Flow ◽  
Content Type ◽  
Linear Differential

Purpose – The purpose of this paper is to demonstrate the eligibility of the Weighted Residual Methods (WRMs) applied to magneto hydro dynamic (MHD) nanofluid flow in divergent and convergent channels. Selecting the most appropriate method among the WRMs and discussing about Jeffery-Hamel flow's treatment in divergent and convergent channels are the other important purposes of the present research. Design/methodology/approach – Three analytical methods (Collocation, Galerkin and Least Square Method) and numerical method have been applied to solve the governing equations. The reliability of the methods is also approved by a comparison made between the fourth-order Runge-Kutta numerical method. Findings – The obtained solutions revealed that WRMs can be simple, powerful and efficient techniques for finding analytical solutions in science and engineering non-linear differential equations. Originality/value – It could be considered as a first endeavor to use the solution of the MHD nanofluid flow in divergent and convergent channels using these kinds of analytical methods along with the numerical approach.

Three weighted residual methods based on Jeffery-Hamel flow

2014 ◽  
Vol 24 (3) ◽  
pp. 654-668 ◽  
Author(s):  
D.D. Ganji ◽  
Mohammad Hatami
Keyword(s):  
Analytical Methods ◽  
Design Methodology ◽  
Least Square Method ◽  
Numerical Approach ◽  
Least Square ◽  
The Other ◽  
Governing Equations ◽  
Science And Engineering ◽  
Content Type ◽  
Linear Differential

Purpose – The purpose of this paper is to demonstrate the eligibility of the weighted residual methods (WRMs) applied to Jeffery-Hamel Flow. Selecting the most appropriate method among the WRMs and discussing about Jeffery-Hamel flow's treatment in divergent and convergent channels are the other important purposes of the present research. Design/methodology/approach – Three analytical methods (collocation, Galerkin and least square method) have been applied to solve the governing equations. The reliability of the methods is also approved by a comparison made between the forth order Runge-Kutta numerical method. Findings – The obtained solutions revealed that WRMs can be simple, powerful and efficient techniques for finding analytical solutions in science and engineering non-linear differential equations. Originality/value – It could be considered as a first endeavor to use the solution of the Jeffery-Hamel flow using these kind of analytical methods along with the numerical approach.

Study on Detection of Epileptic Discharges Based on a Duffing Oscillator Model

2014 ◽  
Author(s):  
Takahiro Murakami ◽  
Yasumi Ukida ◽  
Masami Fujii ◽  
Michiyasu Suzuki ◽  
Takashi Saito
Keyword(s):  
Duffing Oscillator ◽  
Time History ◽  
Least Square Method ◽  
Least Square ◽  
Quantitative Detection ◽  
Model Parameters ◽  
Appearance Time ◽  
Epileptic Discharges ◽  
History Of ◽  
Electrocorticogram Ecog

In order to establish a quantitative detection method for appearance in epileptic discharges (EDs), we propose using the model parameters in a Duffing oscillator, which is a nonlinear mathematical model. Extracting four frequency bands of delta, theta, alpha and beta waves from the time history of the electrocorticogram (ECoG) obtained from rats with induced EDs, we applied a sweep window to the time history for each band. So as to fit the equation for the Duffing oscillator to the time history of the ECoG, we used the least square method to determine the model parameters expressing characteristics of ECoG. The Duffing oscillator has three kinds of vibrational parameters and four kinds of parameters about the amplitude for the driving force with two predominant frequencies contained in ECoG. In order to examine the appearance time of the EDs and the change of ECoG characteristics, we determined the model parameters for each sweep window. When epilepsy occurs, we found that the amount of the parameters related to “conservation”, “dissipation” and “input quantities” increases. On the other hand, the parameter value corresponding to nonlinearity tends to decrease. It is found that the proposed method by the model parameters of the Duffing oscillator can be used in quantitative detection for EDs.

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