Development of Mathematical Equation for Photovoltaic Array Internal Resistance Measurement under Operating Conditions

2016 ◽  
Vol 839 ◽  
pp. 59-64
Author(s):  
Nattawut Khaosaad ◽  
Nipon Ketjoy ◽  
Sarayooth Vaivudh ◽  
Kobsak Sriprapha
Keyword(s):  
Series Resistance ◽  
Crystalline Silicon ◽  
Internal Resistance ◽  
Standard Test ◽  
Operating Conditions ◽  
Resistance Measurement ◽  
Shunt Resistance ◽  
Photovoltaic Array ◽  
Pv Array ◽  
Linear Regression Technique

A novel technique has been developed for PV array internal resistance measurement while keeping the plant in operation in contrary to flash test or basic equation (Eb) for which the modules need to be disconnected from the system. We present an equation developed for the array’s internal resistance measurement for PV technologies namely Amorphous Silicon (a-Si), Poly Crystalline Silicon (p-Si) and Hybrid Crystalline Silicon (HIT). Monthly Measured I-V characteristic curves of PV Array were converted to Standard Test Conditions following the IEC 60891 standard. Multiple regression analysis and linear regression technique were used to develop the equation for estimating the PV array internal resistance. The developed equations (Ed) will find the relationships of the 4 variables that are Series resistance (Rs), Shunt resistance (Rsh), maximum voltage (Vm) and maximum current (Im). The results revealed that the Ed can be applied to measure the PV array internal resistance value with low error margin than Eb. The series resistance calculated using Ed is higher than Eb about 1.11 %, 1.88 % and 0.87 % for a-Si, p-Si and HIT respectively. The shunt resistance calculated using Ed is higher than Eb about 0.07 %, 0.09 % and 0.09% for a-Si, p-Si and HIT respectively.

scholarly journals Correction Procedures for Temperature and Irradiance of Photovoltaic Modules: Determination of Series Resistance and Temperature Coefficients by Means of an Indoor Solar Flash Test Device

2021 ◽  
Vol 65 (2-4) ◽  
pp. 264-270
Author(s):  
Silvia Luciani ◽  
Gianluca Coccia ◽  
Sebastiano Tomassetti ◽  
Mariano Pierantozzi ◽  
Giovanni Di Nicola
Keyword(s):  
Series Resistance ◽  
Experimental Tests ◽  
Standard Test ◽  
Operating Conditions ◽  
Test Device ◽  
Solar Simulator ◽  
Photovoltaic Modules ◽  
Current Voltage ◽  
And Control

The comparison between I-V (current-voltage) curves measured on site and I-V curves declared by the manufacturer allows to detect decrease of performance and control the degradation of photovoltaic modules and strings. On site, I-V curves are usually obtained under operating conditions (OPCs), i.e. at variable solar radiation and module temperature. OPC curves must be translated into standard test conditions (STCs), at a global irradiance of 1000 W/m2 and a module temperature of 25 °C. The correction at STC conditions allows to estimate the deviation between the power of the examined module and the maximum power declared by the manufacturer. A possible translation procedure requires two correction parameters: Rs’, the internal series resistance, and k’, the corresponding temperature coefficient. The aim of this work is to determine the correction parameters carrying out specific experimental tests as indicated by IEC 60891. A set of brand-new photovoltaic modules was experimentally characterized determining their I-V curves by means of an indoor solar flash test device based on a class A+ AM 1.5 solar simulator. Using the OPC I-V curves, obtained at several conditions of irradiance and temperature, it was possible to determine the correction parameters of the photovoltaic modules being considered.

Simulation Model of Photovoltaic and Photovoltaic/Thermal Module/String Under Nonuniform Distribution of Irradiance and Temperature

2016 ◽  
Vol 139 (2) ◽  
Author(s):  
Giuseppe Marco Tina
Keyword(s):  
Smart Grids ◽  
Electrical Energy ◽  
Standard Test ◽  
Nonuniform Distribution ◽  
Operating Conditions ◽  
Uneven Distribution ◽  
Solar Systems ◽  
Pv Array ◽  
Simulink Model ◽  
Pv Cell

The modern concepts of sustainable cities and smart grids have caused an increase in the installation of solar systems in urban and suburban areas, where, due to the presence of many obstacles or design constraints, photovoltaic (PV) modules can operate in operating conditions that are very different from the optimal ones (e.g., standard test conditions, STC). Shading and reflection are the main phenomena that cause uneven distribution of irradiance on PV cells; in turn, they create a nonuniform distribution of PV cell temperatures. The latter problem can also be caused by different ventilation regimes in various parts of the PV array. On the other hand, due to the need to exploit different solar technologies (solar thermal and photovoltaic), problems related to the availability of a useful surface can arise. In this context, there is a technology that produces heat end electrical energy at the same time, such a technology is referred to as a solar hybrid photovoltaic/thermal (PV/T). Here, the uneven distribution of temperature is a design input and its effect depends on both path of the water flow and the PV cell connections. To study the electrical behavior of a PV array under mismatching conditions, a suitable matlab/simulink model has been developed. The model has been tested both numerically and experimentally. Finally, an application of this model in the electrical analysis of a PV/T module is reported, and the results are discussed.

Comprehensive equation-based design of photovoltaic module to investigate its physical parameters and operating conditions used for small application

2020 ◽  
Vol 53 (5-6) ◽  
pp. 850-858 ◽  
Author(s):  
Adeel Saleem ◽  
Nain Liu ◽  
Hu Junjie ◽  
Atif Iqbal ◽  
Ali Waqar
Keyword(s):  
Green Energy ◽  
Operating Conditions ◽  
Modelling And Simulation ◽  
Photovoltaic System ◽  
Photovoltaic Module ◽  
Physical Parameters ◽  
Shunt Resistance ◽  
Simple Method ◽  
Partial Shading ◽  
Photovoltaic Array

Solar photovoltaic is clean and green energy for renewable power generation, which plays a vital role to fulfil the power shortage for any region. Photovoltaic array is quite expensive and has non-linear characteristics. Under varying conditions, it takes much time to give operating curves. Before mount photovoltaic for any application or at any location, there is a vital phase of analysis, modelling, and simulation of the photovoltaic system, which helps to understand the actual behaviour in real conditions. This paper emphasizes on the stepwise procedure of modelling and simulation for the photovoltaic panel, which is proposed to use for the small application. The proposed system provides a reliable, accurate, and simple method to model the photovoltaic system. It takes a flexible solar panel of 180 W as a reference model. The I–V and P–V characteristics are further investigated at different operating conditions such as a variation of irradiance from 1000 to 400 W/m2, variation of temperature from 15 to 70 °C, and vary shunt resistance from higher to low values. The equation-based modelling of the photovoltaic system is built in the MATLAB/Simulink. This methodology allows investigating the photovoltaic system on different operating conditions (varying temperature and irradiance) and physical parameters (ideality factor, series and shunt resistance) along with partial shading effect.

scholarly journals PLTS Transformerless Tegangan 20 kV menggunakan Cascaded H-Bridge Multilevel Inverter

2018 ◽  
Vol 6 (1) ◽  
pp. 16
Author(s):  
ANGGARA BRAJAMUSTHI ◽  
SRI UTAMI ◽  
DJAFAR SODIQ
Keyword(s):  
Power Plant ◽  
Low Voltage ◽  
Boost Converter ◽  
Standard Test ◽  
Multilevel Inverter ◽  
Matlab Simulink ◽  
Plant System ◽  
Photovoltaic Array ◽  
Pv Array ◽  
Dc Power

ABSTRAKAplikasi dari inverter multilevel pada sistem Pusat Listrik Tenaga Surya (PLTS) dapat menghilangkan kebutuhan terhadap transformator, sehingga dapat mengurangi biaya investasi, mengurangi kompleksitas instalasi dan menghilangkan rugi-rugi daya transformator. Pada penelitian ini, sebuah inverter dengan topologi Cascaded H-Bridge Multilevel Inverter dirancang agar mampu mengubah tegangan rendah DC dari beberapa Photovoltaic (PV) array menjadi tegangan fasa-fasa 20 kV AC. Perancangan menghasilkan sebuah inverter 3 fasa 27-level dimana setiap level masing-masing memiliki PV array, DC-DC boost converter, H-bridge inverter, dan keluaran 3 fasa terhubung dengan filter LCL. Setiap komponen dari inverter dan sistem tersebut kemudian dimodelkan pada MATLAB Simulink untuk mensimulasikan kinerja dari setiap komponen dan sistem pada Standard Test Condition (STC) dari modul PV. Pada keadaan STC, daya 3 fasa maksimum yang dapat dihasilkan adalah 1,716 MW atau 68,54% dari daya DC maksimum sebesar 2,5 MWp. Sistem dapat menghasilkan tegangan fasa-fasa keluaran sebesar 20 kV dengan Total Harmonic Distortion (THD) di bawah 5%.Kata kunci: Pusat Listrik Tenaga Surya (PLTS), photovoltaic, Cascaded H-Bridge Multilevel InverterABSTRACTThe application of Multilevel Inverter in a Photovoltaic Solar Power Plant system could eliminate the needs of step-up transformer, which will reduce the system investment cost, simplify the system installation and also eliminate power losses of the transformer. In this paper, an inverter design was proposed with Cascaded H-Bridge Multilevel Inverter topology that is capable of converting low voltage DC power from several PV arrays into 20 kV AC power. The design resulted a 3 phase 27-level inverter where each level in the inverter has its own photovoltaic array, DC-DC boost converter, H-bridge inverter, and the 3 phase output is connected to LCL filter. Each component of the Inverter and the system were then modelled in MATLAB Simulink to simulate the operation of the components and the system at PV Standard Test Condition (STC). At STC, the maximum 3 phase output power of the system is 1,716 MW or 68,54% of maximum DC power of 2,5 MWp. The system can reach 20 kV of output voltage with less than 5% THD. Keywords: Photovoltaic Power Plant System, PV, Cascaded H-Bridge Multilevel Inverter

A novel modeling approach to predict the output performance of photovoltaic modules under different environmental conditions

SIMULATION ◽  
2018 ◽  
Vol 94 (10) ◽  
pp. 861-872 ◽  
Author(s):  
Mohamed Saleem Abdul Kareem ◽  
Manimaran Saravanan
Keyword(s):  
Environmental Conditions ◽  
Series Resistance ◽  
Standard Test ◽  
Maximum Power ◽  
Unknown Parameters ◽  
Shunt Resistance ◽  
Output Performance ◽  
Pv Module ◽  
Current Saturation ◽  
Pv Modules

In this paper, an improved mathematical model of a single-diode photovoltaic (PV) module has been developed to predict the maximum power of the PV modules produced by different PV technologies, such as mono crystalline, multi crystalline, and thin film, under varying environmental conditions. The current–voltage characteristic equation of the PV module is used to extract the PV module’s unknown parameters, such as light generated current, saturation current, ideality factor, series resistance, and shunt resistance at standard test condition (STC). In the proposed PV model, numerical methods are used to calculate the parameters of the PV module at STC, by introducing new equations to estimate the value of series resistance and shunt resistance. By introducing new equations IMPP and VMPP, the maximum power of different PV modules manufactured by various PV technologies at different environmental conditions is then found. In the proposed PV model, the percentage relative error obtained at maximum power is calculated and the experimental results are compared with the models that exist in the literature for different PV modules. The maximum power obtained by the proposed PV model is much closer to that obtained by the Sandia model and Ishaque two-diode model. Furthermore, the output performance of the developed PV model has close agreement with the experimentally obtained data and it is verified practically.

scholarly journals Effect of Measurement Factors on Photovoltaic Cell Parameters Extracting

2017 ◽  
Vol 7 (1) ◽  
pp. 50 ◽  
Author(s):  
El Hadi Chahid ◽  
Mohammed Idali Oumhand ◽  
M’barek Feddaoui ◽  
Mohammed Erritali ◽  
Abdessamad Malaoui
Keyword(s):  
Series Resistance ◽  
Photovoltaic Cells ◽  
Photovoltaic Cell ◽  
Standard Test ◽  
External Factors ◽  
Saturation Current ◽  
Shunt Resistance ◽  
Cell Parameters ◽  
Current Voltage ◽  
Measurement Results

In this paper, we study the influence of external factors on the measurement for the current–voltage (I-V) characteristic of the photovoltaic cell. These factors are the size of the number of measurements, the range of the cell generated voltage and the influence of measures step and mode combination of photovoltaic cells (parallel, serial, or hybrid). The main extracted parameters solar cell are the photocurrent Iph, the reverse diode saturation current I0, the ideality factor of diode n, the series resistance Rs and the shunt resistance Rsh. A method for finding these parameters, according to the single-diode model, was developed by Newton-Raphson’s method using Matlab. To assess the accuracy of this method, measured and calculated I–V characteristics were compared with provided data by the manufacturer at standard test condition (STC). The measurement results showed that these parameters are highly dependent on these four factors.

New Method to Determine the a-Si:H Pin Diode Series Resistance by Noise Measurements

1998 ◽  
Vol 507 ◽  
Author(s):  
F. Blecher ◽  
K. Seibel ◽  
M. Hillebrand ◽  
M. Böhm
Keyword(s):  
Series Resistance ◽  
Partial Information ◽  
Low Noise ◽  
Operating Conditions ◽  
New Method ◽  
Measuring System ◽  
Pin Diode ◽  
Noise Current ◽  
Current Voltage ◽  
Noise Measurements

ABSTRACTThe series resistance limits the linearity of photodiodes and decreases the efficiency of solar cells. It is usually determined from IV-measurements for moderate and high forward current density. This method, however, provides only partial information about Rs, since the series resistance depends on the operating point. An alternative method is based on noise measurements. System noise of the measuring system with a low-noise current-voltage converter has been investigated. A new method for extraction of photodiode series resistance from noise measurements is suggested. Noise measurements are carried out for a-Si:H pin diodes. The series resistance of an amorphous pin diode has been extracted for different operating conditions using the new measurement method.

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