Birinchi Bora

Comparison of curve correction procedure of current and voltage as per IEC 60891 for thin film technology

The performance of PV module is compared through measuring I-V characteristics at STC. But usually in the real outdoors the PV module behaves differently. To estimate the power and energy rating under different climatic conditions, I-V curves are extrapolated by applying corrections. In this paper we have examined I-V curves correction procedure as per IEC 60891 for different temperature and irradiance conditions of three thin film PV technologies viz. CIGS, CdTe, Micro-morph, and a comparison is made with measured data in real outdoor conditions. Deviations from estimated and measured output for three different correction procedures are compared. The correction procedure 3 gives the best results as compared to procedure 1 & procedure 2.

The synergistic effect of air mass on outdoor performance for different PV module in India

ABSTRACT The effect of air mass (AM) on the performance of multi-crystalline silicon (m-Si), amorphous silicon (a-Si), and hetero-junction with intrinsic thin layer (HIT)-technology-based photovoltaic (PV) modules are evaluated for representative day of four seasons during the year 2011 for composite climate of India. To find the best performing PV module technology with respect to AM at the site, annual energy yields and performance ratio against different AM bands (AM 1–4.5) are plotted. It is found that HIT modules perform better than m-Si and a-Si at each AM band. Annual energy yields for all three technologies decrease with increasing order of AM bands. The performance ratio for HIT and m-SI modules initially increases and then decreases with increasing order of AM bands. However, for a-Si modules, the performance ratio decreases with increasing order of the AM bands.

Modeling the performance of HIT technology for composite climatic zone of India

This paper presents performance modeling of HIT technology modules based on weather parameters. A comparison has been made between experimental data, and the calculated data using PVUSA and matrix formation methods. It is found that for the reported model, the values of percentage of confidence for the error band -10 % to +10 % for different seasons are ranging from 70% to 95%. But for the monsoon season the confidence value of percentage is low as compared to others seasons. The modeling is done with different clearness index value for cloudy and clear sky condition and its confidence value varies from 76% to 95%.

Analysis of temperature effect on optimum sizing of solar photovoltaic water pumping system

Indian ambient condition varies widely during different seasons which can influence the performance and optimum PV array sizing of solar water pumping system. It is observed that water output of the same pump varies seasonally due to change in weather. Most of solar pumps use Variable Frequency Drives (VFD) controllers for DC/ AC conversion and driving the solar pumps. However, due to absence of proper MPPT in VFD, there is a difference between MPP voltage and the operating array voltage. Further, due to strong influence of temperature, PV array operating voltage decreases in summer because of higher temperature. The power available at operating voltages decreases significantly during summer, reducing water output. Due to this reason solar pumps using VFD drivers perform poorly during summer.

Estimation of operating condition frequency distribution and power prediction by extending application of IEC 61853-1 standard for different technology photovoltaic modules

Photovoltaic (PV) module performance varies under actual outdoor environmental conditions, which can be better analyzed by relating performance with the frequency of different operating conditions. In this paper, the frequency of occurrence under the IEC 61853-1 standard has been exploited for proposing the concept of the frequency distribution of operating conditions for photovoltaic modules and analyzed for amorphous silicon, heterojunction with intrinsic thin-layer, and multi-crystalline silicon PV technology modules simultaneously, from the measured data of 2 years at the site of the National Institute of Solar Energy, India. A relative comparison has been presented between different technology modules, and the most frequent operating condition (MFOC) has been obtained from the proposed frequency distribution under the IEC 61853-1 standard. The results show that MFOC and the maximum energy contribution of all technology modules co-existed under the same IEC 61853-1 condition centered at an irradiance of 800 W/m2 and a module temperature of 50 °C, which could be advantageous while formulating an alternate standard for better performance assessment as compared to the standard test condition (STC). The power deviation from STC under MFOC was estimated in the range of 23%–37% for different technology modules, which can lead to a significant impact in performance estimation. While considering the significance of MFOC, a model applicable to modules of variable sizes has been presented for future power prediction under MFOC. The results of the presented model showed good agreement with experimental results for all the technology modules. This work can be helpful for planners, installers, financers, and consumers for better estimation of PV performance.Photovoltaic (PV) module performance varies under actual outdoor environmental conditions, which can be better analyzed by relating performance with the frequency of different operating conditions. In this paper, the frequency of occurrence under the IEC 61853-1 standard has been exploited for proposing the concept of the frequency distribution of operating conditions for photovoltaic modules and analyzed for amorphous silicon, heterojunction with intrinsic thin-layer, and multi-crystalline silicon PV technology modules simultaneously, from the measured data of 2 years at the site of the National Institute of Solar Energy, India. A relative comparison has been presented between different technology modules, and the most frequent operating condition (MFOC) has been obtained from the proposed frequency distribution under the IEC 61853-1 standard. The results show that MFOC and the maximum energy contribution of all technology modules co-existed under the same IEC 61853-1 condition centered at an irradiance ...

Mitigation of PID in commercial PV modules using current interruption method

Potential-induced degradation (PID) is known to have a very severe effect on the reliability of PV modules. PID is caused due to the leakage of current from the cell circuit to the grounded frame under humid conditions of high voltage photovoltaic (PV) systems. There are multiple paths for the current leakage. The most dominant leakage path is from the cell to the frame through encapsulant, glass bulk and glass surface. This dominant path can be prevented by interrupting the electrical conductivity at the glass surface. In our previous works related to this topic, we demonstrated the effectiveness of glass surface conductivity interruption technique using one-cell PV coupons. In this work, we demonstrate the effectiveness of this technique using a full size commercial module susceptible to PID. The interruption of surface conductivity of the commercial module was achieved by attaching a narrow, thin flexible glass strips, from Corning, called Willow Glass on the glass surface along the inner edges of the frame. The flexible glass strip was attached to the module glass surface by heating the glass strip with an ionomer adhesive underneath using a handheld heat gun. The PID stress test was performed at 60°C and 85% RH for 96 hours at −600 V. Pre- and post-PID characterizations including I-V and electroluminescence were carried out to determine the performance loss and affected cell areas. This work demonstrates that the PID issue can be effectively addressed by using this current interruption technique. An important benefit of this approach is that this interruption technique can be applied after manufacturing the modules and after installing the modules in the field as well.

Reliabilitystudy of Solar PV Power Production In Terms Of Weather Parameters Using Monte Carlo Simulation

In this study the comprehensive reliability in terms of clearness index for power production of HIT, amorphous silicon & multi-crystalline silicon (m-cSi) technologies has been analyzed. The energy estimation of these three technologies is done based on regression, and deviation in the measured and estimated values is also reported. It has been found that for winter season, HIT technology module is the most reliable for overcast and partly cloudy conditions between the HIT, amorphous silicon &m-cSitechnologies. For summer season, amorphous Silicon technology shows the highest reliability for clear sky condition, m-cSi has the highest reliability for partly cloudy and HIT technology for overcast condition. HIT technology shows higher reliability both in the post monsoon and autumn season for clear sky and partly cloudy index conditions. The error in the estimations has been reduced by increasing the number of iterations. Keyword:Monte Carlo; SPV Module; Environment Parameter; Simulation; Reliability -------------------------------------------------------------------------------------------------------------------------------------Date of Submission: 13-07-2017 Date of acceptance: 15-07-2017 --------------------------------------------------------------------------------------------------------------------------------------

Initial outdoor performance analysis of different PV module technology

This paper presents initial outdoor performance analysis of different PV modules. In this study CdTe, CIGS and Multi-crystalline Silicon technology were tested in outdoor conditions as received from manufacturer. No treatment is given before the testing of the module. I-V translation methodology from IEC 60891 was used to analyse the initial performance of the PV modules at Standard Test Conditions (STC). For all modules, power rating was calculated at STC and frequency distribution of all the power ratings from different observations were plotted using histogram. For each module, the power rating with highest frequency of occurrence was selected and its percentage deviation from the name plate rating was calculated to check initial performance. It was found that many of the modules were not performed as per nameplate value initially at outdoor condition.

Visual and electrical degradation of 22 years field age monocrystalline silicon PV module in composite climate of India

This paper presents the analysis of visual and electrical degradation of 22 years field aged mono crystalline silicon PV module in composite climate of India. The visual degradation data is correlated with the electrical performance degradation data. Average power degradation rate for the studied PV module is more than 1% per year. The discoloration of back-sheet, bus-bar, cell inter connect ribbon, string interconnect ribbon and solar cell are found to be obvious in all the modules, however the percentage of defects are different.

Effect of series resistance on degradation of isc, power output and fill factor of HIT technology

This paper presents the Dependency of Series Resistance over a wide range of Irradiance And Temperature for HIT Technology As Per IEC 61853-1. A quantitative assessment of the effect of series resistance on electrical performance parameters of HIT technology has been studied from long term outdoor performance data. Degradation of the performance of HIT technology after one year of outdoor exposure has been studied and observed that with the increase of Series resistance outdoor exposure fill factor, power and Isc decreases.