Renewable energy (RE) has become a focal point of interest as an alternative source of energy to the traditional fossil fuel and other energy sources due to the fact that it is more environmentally ...friendly, abundant and economically feasible. Many countries aggressively promote feed-in tariff schemes and solar photovoltaic (PV) systems have become one of the fastest growing RE sources that can be integrated into the grid distribution network. This paper reviews the recent development of grid-connected PV (GPV) generation systems comprising of several sub-components such as PV modules, DC-DC converter, maximum power point tracking (MPPT) technique, and an inverter. In addition, various grid synchronization and islanding detection methods are elaborated. The future key challenges to build a smart and efficient GPV generation system were also presented.
In a Battery Management System (BMS), cell balancing plays an essential role in mitigating inconsistencies of state of charge (SoCs) in lithium-ion (Li-ion) cells in a battery stack. If the cells are ...not properly balanced, the weakest Li-ion cell will always be the one limiting the usable capacity of battery pack. Different cell balancing strategies have been proposed to balance the non-uniform SoC of cells in serially connected string. However, balancing efficiency and slow SoC convergence remain key issues in cell balancing methods. Aiming to alleviate these challenges, in this paper, a hybrid duty cycle balancing (H-DCB) technique is proposed, which combines the duty cycle balancing (DCB) and cell-to-pack (CTP) balancing methods. The integration of an H-bridge circuit is introduced to bypass the selected cells and enhance the controlling as well as monitoring of individual cell. Subsequently, a DC–DC converter is utilized to perform CTP balancing in the H-DCB topology, efficiently transferring energy from the selected cell to/from the battery pack, resulting in a reduction in balancing time. To verify the effectiveness of the proposed method, the battery pack of 96 series-connected cells evenly distributed in ten modules is designed in MATLAB/Simulink software for both charging and discharging operation, and the results show that the proposed H-DCB method has a faster equalization speed 6.0 h as compared to the conventional DCB method 9.2 h during charging phase. Additionally, a pack of four Li-ion cells connected in series is used in the experiment setup for the validation of the proposed H-DCB method during discharging operation. The results of the hardware experiment indicate that the SoC convergence is achieved at ~ 400 s.
Summary
Different solar tracking variables have been employed to build intelligent solar tracking systems without considering the dominant and optimum ones. Thus, several low performance intelligent ...solar tracking systems have been designed and implemented due to the inappropriate combination of solar tracking variables and intelligent predictors to drive the solar trackers. This research aims to investigate and evaluate the most effective and dominant variables on dual‐ and single‐axis solar trackers and to find the appropriate combination of solar variables and intelligent predictors. The optimum variables will be found by using correlation results between different variables and both orientation and tilt angles. Then, to use the selected variables to develop different intelligent solar trackers. The results revealed that month, day, and time are the most effective variables for horizontal single‐axis and dual‐axis solar tracking systems. Using these variables in cascade multilayer perceptron (CMLP) and multilayer perceptron (MLP) produced high performance. These predictors could predict both orientation and tilt angles efficiently. It is found that day variable is very effective to increase the performance of solar trackers although day variable is neither correlated nor significant with both orientation and tilt angles. Linear regression predicted less than 70% of the given data in most cases, whereas nonlinear models could predict the optimum orientation and tilt angles. In single‐axis tracker, month, day, and time variables achieved prediction rates of 96.85% and 96.83% for three hidden layers of MLP and CMLP, respectively, whereas the MSE are 0.0025 and 0.0008, respectively. In dual‐axis solar tracker, MLP and CMLP predicted 96.68% and 97.98% respectively, with MSE of 0.0007 for both.
This research aims to investigate and evaluate the most effective and dominant variables on dual and horizontal single‐axis solar trackers and to find the appropriate combination of solar variables and intelligent predictors. The optimum variables will be found by using correlation results between different variables and both orientation and tilt angles. In single‐axis tracker, month, day, and time variables achieved predictions rates of 96.85% and 96.83% for three hidden layers of MLP and CMLP, respectively. In dual‐axis solar trackers, MLP and CMLP predicted 96.68% and 97.98% respectively.
The study of the effect of soiling on photovoltaic (PV) system performance is a crucial issue judging from numerous research publications. The reduction in the PV system performance is because of ...soiling that differs from one climatic region to another. In this research, the power losses due to soiling of the PV systems in Malaysia based on the calculation of a dirt derating factor <inline-formula><tex-math notation="LaTeX">({{f_{{\rm{dirt}}})</tex-math></inline-formula> were determined. A new mathematical model to correlate <inline-formula><tex-math notation="LaTeX">{f_{{\rm{dirt}}}</tex-math></inline-formula> and the PV module area was developed based on the regression analysis from a site data location. The findings indicate that the effect of soiling reduces the PV systems output power at an average of 26.22% at Setiu over a period of 12 months. From this study also, a new mathematical model was created for <inline-formula><tex-math notation="LaTeX">{f_{{\rm{dirt}}}</tex-math></inline-formula> forecasting in the research site. Uniquely, this mathematical model can do the prediction by only known PV module area or size as the independent variable, much simpler than using the multivariables equation.
Artificial Intelligence is widely used in solar applications. Adaptive Neural Fuzzy Inference System (ANFIS) principle is one of the intelligent techniques that is sufficient to be used in control ...systems. This paper proposes two new efficient intelligent solar tracking control systems based on ANFIS principle. The aim of this paper is to design and implement efficient single and dual-axis solar tracking control systems that can increase the performance of solar trackers, predict the trajectory of the sun across the sky accurately, and minimize the error, therefore, maximize the energy output of solar tracking systems. Experimental data are used to train and test the proposed solar tracking controllers by using month, day and time as input variables to predict the optimum positions for solar tracking systems (tilt/orientation angles). The proposed ANFIS models have been evaluated to find its capability and robustness in tracking the optimum angles that gain the maximum solar radiation. It is found that the proposed controllers are optimum to control solar tracking systems with high prediction rate and the low error rate. Besides, the selected variables along with the selected architecture could successfully predict the optimum tilt and orientation angles. The proposed models provide superior results with five membership functions, and it could obtain high performance for both single-axis and dual-axis solar tracking systems.
Building-integrated solar photovoltaic (BIPV) systems have gained attention in current years as a way to recover the building’s thermal comfort and generate sustainable energy in building structures. ...BIPV systems can provide shade against sunshine while generating ancillary electrical power. Over the last decades, engineers have been trying to improve the efficiency of BIPV systems. BIPV systems with various installation types, including rooftop, balcony, curtain, sunshade, and wall façade types, are being constantly researched and intensively presented for improving power efficiency and reducing air-conditioning use. This work provides an overview of solar BIPV systems and focuses particularly on existing applications of the bifacial type of BIPV systems. The motivation and an overview of BIPV systems are first introduced, followed by the study methodology considered and the contributions. This work discusses PV technologies of bifacial PVs (monocrystalline and polycrystalline bifacial modules), BIPV installation curtains, rooftop, flat rooftop, transparent faced, balcony windows (transparent), wall opaque facade, flat roof-faced, and skylight sunshade types, simulation and optimization software (simulation software and future trends), zero-energy BIPV technology, and optimization techniques of BIPV systems. Last, suggestion amendments to the current BIPV design that possibly contribute to growing the system’s effectiveness, reliability, and cost as future design theories for the whole system are presented.
The main factor that drives the aging of power semiconductor modules is the thermally induced stress caused by the maximum temperature and temperature swings. This thermally induced stress is usually ...counteracted in passive designs with oversizing of components, which brings additional cost to the system. This is a major limitation of future power electronic systems that are required to be more reliable with reasonable cost and for many applications to be lighter and smaller. Active thermal control (ATC) is a possibility to reduce the thermal stress of components during real-time operation without the need to modify the expensive converter power stage. Many studies have shown the potential of ATC to not only extend the lifetime of power converters because of the reduced stress, but also to increase the converter devices utilization by pushing them into their thermal limits with proper control. This makes ATC an appealing way to realize the contradicting reliability, cost, and power density requirements. This paper provides an overview of the benefits and objectives, structure, and implementation possibilities of ATC. It also provides and overview of the limitations and disadvantages of many ATC strategies. Based on this discussion, it highlights key issues that must be addressed by future research. Among them is minimizing the impact of different ATC strategies on the power losses, operational cost, and output voltage and current quality.
Microcontroller-based methods for zero-crossing detection (ZCD) presented in the literature employ external integrated circuits (ICs) to sense electrical signals, and their algorithms are ...sophisticated. Therefore, this paper proposes a simple open-loop sensorless microcontroller-based algorithm for determining zero-crossing (ZC) instants of sinusoidal signals that can be used for phase detection (PD) in phase-locked loops (PLLs). The proposed algorithm employs a built-in rounding function in the Arduino software environment. The developed system was simulated using MATLAB Simulink® to demonstrate its prominent features in recognizing zero-crossing points in two cases: a pure sine signal at a grid frequency of 50 Hz, and distorted signals with total harmonic distortions (THDs) of 10 %, 20 %, 30 %, and 40 %. In the simulation, the proposed system exhibited outstanding results in terms of simplicity, accuracy, and robustness. However, in practice, accuracy and robustness are relative terms, because they depend on the specifications of the microcontroller board. In this study, a low-cost microcontroller board, Arduino Uno, was used. The Uno is an 8-bit board with a 16-MHz clock speed. Therefore, an error in terms of the phase shift emerged in the output signal, which was measured to be 0.0314 rad at 50 Hz. Moreover, the proposed system detected the ZC points of distorted signals with a THD of up to 30 % without using filters and failed at a THD of 40 %. Finally, the ZC points were identified in a three-phase system, and the validity of applying the proposed method to polyphase systems was demonstrated.
Solar photovoltaic technology is one of the most important resources of renewable energy. However, the current solar photovoltaic systems have significant drawbacks, such as high costs compared to ...fossil fuel energy resources, low efficiency, and intermittency. Capturing maximum energy from the sun by using photovoltaic systems is challenging. Several factors that affect the energy output of such systems include the photovoltaic material, geographical location of solar irradiances, ambient temperature and weather, angle of sun incidence, and orientation of the panel. This study reviews the principles and mechanisms of photovoltaic tracking systems to determine the best panel orientation. The tracking techniques, efficiency, performance, advantages, and disadvantages of simple tracking systems are compared with those of state-of-the-art tracking systems. Diverse types of solar tracking systems based on their technologies and driving methods will be presented and categorized.The future trends of tracking systems are also highlighted.
Design and Development of 100W Solar Power Systems for ODAS Buoy Mohamed Hariri, Muhammad Hafeez; Din, Abdul Sattar; Arshad, Mohd Rizal ...
2023 IEEE IAS Global Conference on Renewable Energy and Hydrogen Technologies (GlobConHT),
2023-March-11
Conference Proceeding
This paper presents the design and the development of \boldsymbol{100}\mathbf{W} solar power systems for a scientific buoy known as Ocean Data Acquisition System (ODAS) Buoy. There are two separate ...solar power systems proposed in this paper; one for the buoy and the other one for a ground station. The characteristics of solar data, type of PV modules, total load demand, battery sizing, and converter and inverter ratings are major factors that need to be considered in designing and developing the standalone PV systems. The results have shown that this method has provided reliable and sufficient battery storage to power all the loads continuously without any interruption.
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