Leakage Current Mitigation of Photovoltaic System Using Optimized Predictive Control for Improved Efficiency

This paper proposes an optimized predictive control strategy to mitigate the potential leakage current of grid-tied photovoltaic (PV) systems to improve the lifespans of PV modules. In this work, the PV system is controlled with an optimized predictive control algorithm that selects the switching voltage vectors intelligently to reduce the number of computational burdens. Thus, it improves the dynamic performance of the overall system. This is achieved through a specific cost function that minimizes the change in common-mode voltage generated by the parasitic capacitance of PV modules. The proposed controller does not require any additional modulation schemes. Normalization techniques and weighting factors are incorporated to obtain improved results. The steady state and dynamic performance of the proposed control scheme is validated in this work through simulations and a 600 W experimental laboratory prototype.

PERFORMANCE OF DIFFERENT PHOTOVOLTAIC TECHNOLOGIES FOR AMORPHOUS SILICON (A-SI) AND COPPER INDIUM GALLIUM DI-SELENIDE (CIGS) PHOTOVOLTAIC MODULES

In this work, the analysis of performance of two types of photovoltaic (PV) (Amorphous Silicon (a-Si) Copper Indium Gallium Diselenide (CIGS) technologies were achieved out under under Iraqi (Baghdad)climate conditions. The elevation of the selected site is 9 m above ground level. The experimental work covered the eight commercially available PV technologies. The two technologies that employed in this work are, Amorphous Silicon (a-Si) and Copper Indium Gallium Diselenide (CIGS). The total period of the experimental work was 7 months, and the data were analyzed simultaneously. Special attention is given to the influence of temperature and solar radiation the performance of the PV modules. Where, it was proposed a simple I-V curve test for PV modules. The results showed that the proposed system successfully experimentally extracted I-V curves of the selected two PV modules (amorphous and CIGS solar modules). The maximum values of power (Pmax) at solar radiation intensity 750 W/m² are 2.742 W, and 2.831 W for amorphous silicon and copper indium gallium di-selenide respectively. This is occurred because the lowest solar module operating temperature (19 oC and 17 oC for solar radiation 750 and 1000 W/m2 respectively) and ambient temperature (7 oC) and for Jan., 2021 than other months. Consequently, the same behavior for the two modules at solar irradiance 1000 W/m2 with the highest power value; 2.680 W, and 3.198 W of amorphous silicon and copper indium gallium di-selenide respectively. Furthermore, the minimum values of power (Pmax) at solarradiation intensity 750 W/m² are 2.530, and 2.831 for amorphous silicon and copper indium gallium di-selenide respectively because we have the highest solar module operating temperature (57 oC, and 55 oC respectively) and ambient temperature (45 oC) for April, 2021 than other months. Consequently, the same behavior for the two modules at solar irradiance 1000 W/m2 with the highest power value; 2.680 W, and 3.198 W of amorphous silicon and copper indium gallium di-selenide respectively. The highest efficiency can be notes for CIGS solar module with a value 7.3%, while the lowest one is 5.5% for amorphous solar module.

Photovoltaic Module Electrical Efficiency Enhancement Using Nano Fluids and Nano-Paraffin

Today, photovoltaic modules have become accepted by the public and scientists in the production of clean electricity and as a possible alternative to electricity produced from fossil fuels. These modules suffer from a deterioration in their electrical efficiency as a result of their high temperature. Several researchers have proposed the use of high-efficiency hybrid photovoltaic (PV/T) systems that can cool PV modules and also produce hot water. Improving the PV modules’ electrical efficiency increases the investment attraction and commercialization of this technology. The possibility of restoring the electrical efficiency of the photovoltaic panel that was lost due to its high temperature was investigated in this study. A PV/T system designed to operate with a paraffin-filled thermal tank attached to the PV module was used. Inside the paraffin is a heat exchanger that circulates inside a nanofluid. This design is adopted to cool down the PV module temperature. The study was carried out in the climatic conditions of the month of May in the city of Baghdad - Iraq. The proposed PV/T system’s electrical efficiency was compared with similar systems from the literature. The proposed system has achieved an obvious enhancement as its electrical efficiency was 13.7%.

Energy efficiency using Distributed Generation; Cafeteria of Engineer Faculty Campeche, Mexico

In the present work, an integral design of the cafeteria located at Faculty of Engineering of Autonomous University of Campeche is carried out. Four scenarios of Photo Voltaic (PV) generation have been studied. A 14 PV modules arrangement of 440 each, with azimuthal angle of 180º and a slope angle of 15º; the other is similar to the previous, but the slope angle was 19.85º. The following was a 24 PV modules arrangement of 440, with an azimuthal angle of 218º and a slope angle of 15º. The last arrangement consists of 24 PV modules arrangement of 440, with azimuthal angle of 218º and a slope angle of 19.85º. Where all of them are associated with the economic aspect to obtain greater efficiency of the plant with minimum recovery time. The free software System Advisor Model (SAM) developed by the National Renewable Energy Laboratory (NREL) has been employed. Complete seasonal analysis has also been performed considering Gran Demanda Media Ordinaria en México (GDMO de CFE in Mexico) within the period January 2020 to March 2021. The best results are energy generation 17,570 kWh. Capacity factor 19%. Energy performance 1,671 kWh/kW. Performance relation 0.74. Leveled cost 5.39 ¢/kWh. And return on investment in 0.6 years. The GD-PV plant prevents the emission into the atmosphere of 778.85 kg of CO2 equivalent.

Feasibility Study of the Technical and Economic Performance of Grid-Connected PV System for Selected Rooftops in UTHM

This paper presents the feasibility study of the technical and economic performances of grid-connected photovoltaic (PV) system for selected rooftops in Universiti Tun Hussein Onn Malaysia (UTHM). The analysis of the electricity consumption and electricity bill data of UTHM campus show that the monthly electricity usage in UTHM campus is very high and expensive. The main purpose of this project is to reduce the annual electricity consumption and electricity bill of UTHM with Net Energy Metering (NEM) scheme. Therefore, the grid-connected PV system has been proposed at Dewan Sultan Ibrahim (DSI), Tunku Tun Aminah Library (TTAL), Fakulti Kejuruteraan Awam dan Alam Bina (FKAAS) and F2 buildings UTHM by using three types of PV modules which are mono-crystalline silicon (Mono-Si), poly-crystalline silicon (Poly-Si) and Thin-film. These three PV modules were modeled, simulated and calculated using Helioscope software with the capacity of 2,166.40kWp, 2,046.20kWp and 1,845kWp respectively for the total rooftop area of 190,302.9 ft². The economic analysis was conducted on the chosen three installed PV modules using RETScreen software. As a result, the Mono-Si showed the best PV module that can produce 2,332,327.40 kWh of PV energy, 4.4% of CO₂ reduction, 9.3 years of payback period considering 21 years of the contractual period and profit of RM4,932,274.58 for 11.7 years after payback period. Moreover, the proposed installation of 2,166.40kWp (Mono-SI PV module) can reduce the annual electricity bill and CO2 emission of 3.6% (RM421,561.93) and 4.4% (1,851.40 tCO₂) compared to the system without PV system.

Design and Implementation of a Flexible Photovoltaic Emulator Using a GaN-Based Synchronous Buck Converter

In order to efficiently facilitate various research works related to power converter design and testing for solar photovoltaic (PV) generation systems, it is a great merit to use advanced power-converter-based and digitally controlled PV emulators in place of actual PV modules to reduce the space, cost, and time to obtain the required scenarios of solar irradiances for various functional tests. This paper presents a flexible PV emulator based on gallium nitride (GaN), a wide-bandgap (WBG) semiconductor, and a based synchronous buck converter and controlled with a digital signal processor (DSP). With the help of GaN-based switching devices, the proposed emulator can accurately mimic the dynamic voltage-current characteristics of any PV module under normal irradiance and partial shading conditions. With the proposed PV emulator, it is possible to closely emulate any PV module characteristic both theoretically, based on manufacturer’s datasheets, and experimentally, based on measured data from practical PV modules. A curve fitting algorithm is used to handle the real-time generation of control signals for the digital controller. Both simulation with computer software and implementation on 1 kW GaN-based experimental hardware using Texas Instruments DSP as the controller have been carried out. Results show that the proposed emulator achieves efficiency as high as 99.05% and exhibits multifaceted application features in tracking various PV voltage and current parameters, demonstrating the feasibility and excellent performance of the proposed PV emulator.