Photovoltaic system performance is influenced by a variety of factors such as irradiance, temperature, shading, degradation, mismatch losses, soiling, etc. Especially shading, complete or partial, can have a significant contribution to the reduction of power output, depending mainly on the PV array configuration, the shading pattern and the existence of bypass diodes incorporated in the PV module design. In order to obtain the maximum power from a PV generator, it is of great importance to evaluate the complex effects of shading on the P-V and I-V curves.
This paper investigates the performances of different photovoltaic (PV) array under several shading condition. Four types of photovoltaic array configuration scheme which are ‘Series’ (S), Series-Parallel’ (SP), Total-Cross-Tied’ (TCT), and ‘Bridge-Link’ (BL) array topologies were tested by applying a 6x6 PV array under 6 different shading scenarios. The modeling is developed using Matlab/Simulink. The performances and output characteristics of photovoltaic array are compared and analyzed. System engineer can use the detailed characteristics of different array configuration to approximate the outcome power and pick the best configuration of the system by concerning the current natural condition to enhance the overall efficiency.
Power-Voltage (P-V) curve and Current-Voltage (I-V) curve determine the performance of the PV system. In this work, the arrangements of the PV module were reconstructed by adding the number of PV module in 3 strings configuration from 5 to 45. This method enhance the performance of the PV system as it able to show the characteristic of the P-V and I-V curve during partial shading and maximum irradiance despite higher number of PV panel. This study focuses on improving the PV array configuration and simulation speed of the PV panel. The simulation of small size PV array is possible, but the problem lies when the number of string and PV module used increases. New PV array configuration is flexible and easy to add string and increase the number of PV module. PV array configuration was modeled using MATLAB/SIMULINK software.
Electricity are commonly generated from several types of energy resources such as fossil and nuclear energy. However, due to emission of carbon dioxide from both sources, renewable energy is introduced to provide a clean and secure sustainable energy. One of the potential renewable energy application is Photovoltaic (PV) system; namely grid-connected photovoltaic (GCPV) system and stand-alone photovoltaic (SAPV) system. In this study, a mathematical approach of SEDA’s GCPV sizing model is implemented to size a 4kWp of a retrofitted GCPV system by the method claimed to be the best practice mathematical design model under tropical climate Malaysia. The outcome of the sizing approach will then be evaluated with HelioScope software, one of commercial simulation tools available in current market. The final result obtained from both methods shows that the final PV array configuration is 1 x 12 (parallel x series) which is in agreement to the actual installed system.
The work presents a tropical case study of sizing 3 kWp retrofitted grid-connected photovoltaic system (GCPV) installed in Klang, Malaysia. The sizing was based on customer’s budget requirement of RM 22, 500 and conducted through a designated mathematical approach. The mathematical approach involved technical aspects which aligns the voltage and current specifications of both PV array and inverter. Besides, this approach includes possible severe climatic condition of solar irradiance and ambient temperature variations. By implementing the sizing mathematical approach in this study, the final PV array configuration is 1 x 9 (1 parallel x 9 series). This study was also conducted to compare between the actual and the predicted energy yield to reflect customer satisfaction. Based on the result, the percentage differences are acceptable for February and March 2018. Interestingly, the percentage difference for January 2018 was over-predicted and the abnormality was suggested to be resulted from the inaccuracy of the Peak Sun Hour (PSH) estimation. In conclusion, this study is significant as an overview on the sizing and performance reliability of GCPV system in tropical Malaysia to meet up the customer satisfaction.
This paper presents a new systematic approach to analyze all possible array configurations in order to determine the most optimal dense-array configuration for concentrator photovoltaic (CPV) systems. The proposed method is fast, simple, reasonably accurate, and very useful as a preliminary study before constructing a dense-array CPV panel. Using measured flux distribution data, each CPV cells’ voltage and current values at three critical points which are at short-circuit, open-circuit, and maximum power point are determined. From there, an algorithm groups the cells into basic modules. The next step isI-Vcurve prediction, to find the maximum output power of each array configuration. As a case study, twenty differentI-Vpredictions are made for a prototype of nonimaging planar concentrator, and the array configuration that yields the highest output power is determined. The result is then verified by assembling and testing of an actual dense-array on the prototype. It was found that theI-Vcurve closely resembles simulatedI-Vprediction, and measured maximum output power varies by only 1.34%.
Total-Cross-Tied (TCT) solar array configuration has more output power under uniform irradiance condition (un-shade case) among all conventional solar photovoltaic (SPV) array configurations but reduced array power under non-uniform irradiance cases (shading cases). To improve the performance of TCT array configuration under shading cases by using rearrangement or repositioning of existing photovoltaic (PV) modules in TCT configuration to new optimal locations within a TCT array configuration with shade dispersion technique. In this rearranged method, repositioning the modules based on puzzle pattern without altering the electrical connections among modules in an SPV array. The shading on PV modules are dispersed by changing the position of PV modules to optimal locations within SPV array so the performance of conventional TCT configuration will be improved. In this paper proposed an optimal TCT configurations, it requires a minimum number of electrical connections or ties between array modules and it depends on the shaded modules location in SPV array and also the proposed method reduces the wiring losses, mismatch losses. For this analysis, MATLAB/Simulink software is used for modeling and simulation of 6x6 size different rearrangement based TCT and proposed optimal SPV array configurations under one un-shaded case and fourteen different shading cases.
Power Enhancement in Partial Shaded Photovoltaic System Using Spiral Pattern Array Configuration Scheme
