The maximum power point tracking (MPPT) techniques are used in photovoltaic (PV) systems to fully utilize the PV array output power that depends on the change in PV radiation and ambient temperature. In this paper, mo...
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The maximum power point tracking (MPPT) techniques are used in photovoltaic (PV) systems to fully utilize the PV array output power that depends on the change in PV radiation and ambient temperature. In this paper, modified perturb and observe (MP&O) algorithm is proposed to be more efficient for MPPT of grid-connected PV system. The results of this MP&O algorithm are shown to track the maximum energy under fast-changing weather conditions at two cases of solar radiation changes, the first case is the solar radiation change in ramp mode, and the second case is the displaying under random change of solar radiation. The maximum power point (MPP) can be obtained by controlling the operating period that is fed on the MOSFET gate within the boost converter. In addition, the control technique used with the three-phase inverter is a dynamic-based PI controller. The MP&O algorithm is built on the determination of the maximum effective point on the property curve and is similar to the traditional scheme. The idea of this comparison is to use the change in solar radiation to determine the difference between the working point of the PV solar array and the number of sectors. The performance is estimated and compared by mathematical investigation and simulation analysis. The proposed method offers high performance and accurate tracking in rapidly varying weather environments.
This work describes the behavior of a piezoelectric energy harvesting system that uses a single inductor and the concept of energy investment for the whole of building a behavioral model for the harvester and a high-l...
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This work describes the behavior of a piezoelectric energy harvesting system that uses a single inductor and the concept of energy investment for the whole of building a behavioral model for the harvester and a high-level system analysis approach. The harvester modules and control were specified and described in Verilog-A to fully model the energy harvester operation. Simulation results have shown the harvesting mechanism based on the concept of energy-investment and model accuracy, and the effect of the invested energy on the battery charging profile, highlighting the trade-off a constant energy investment time poses to the harvester, unable to meet the requirements a non-constant input vibration sets to system. An adaptive energy investment time based on a P&O algorithm was proposed to cope with this trade-off and added to the harvester model. Performed simulations with adaptive energy investment have shown improved energy harvesting, and that such improvement increases as the input power increases, since the system can tune the energy investing mechanism to the input vibrations.
There are not many studies conducted in the implementation of maximum power point tracking (MPPT) methods for heaving wave energy converters (WECs). An assessment of damping control using various MPPT methods for heav...
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There are not many studies conducted in the implementation of maximum power point tracking (MPPT) methods for heaving wave energy converters (WECs). An assessment of damping control using various MPPT methods for heaving WEC was conducted in this study. Damping control was implemented using a DC-DC boost converter. The duty cycle for MPPT was determined using a perturb and observe algorithm. This assessment study determines the following for applying MPPT for heaving WECs: best location for the observing parameters;best performance index for the MPPT;and effect of averaging the performance index. Three locations for the observing parameters (mechanical parameters near the source, electrical parameters at the load, and electrical parameters between the source and load) and three performance indices (maximising power, minimising impedance, and maximising admittance) were assessed and evaluated. Finally, the effects of applying the running mean and conventional instantaneous value on the performance index were compared. Various scenarios using nine MPPT methods were tested using simulated regular and irregular sea states. The test results were validated experimentally using a simple and low-cost hardware-in-the-loop (HIL) scheme. The HIL scheme was developed using off-the-shelf devices that can be used for any topology of WECs. The results showed that the MPPT method has an optimum performance by using the performance index for maximising power, using observing parameters between the source and the load, and deploying conventional instantaneous values for the observing parameters.
This paper proposes a novel high voltage gain structure of DC-DC converter with soft-switching ability for photovoltaic (PV) applications. A small size coupled inductor with one magnet core is utilized to improve the ...
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This paper proposes a novel high voltage gain structure of DC-DC converter with soft-switching ability for photovoltaic (PV) applications. A small size coupled inductor with one magnet core is utilized to improve the voltage conversion ratio in the proposed converter. The converter has one active MOSFET with low conducting resistance (RDS-ON), which in turn reduces the conduction losses and complexity of the control section. Due to the low input current ripple, the lifetime of the input PV panel is increased, and the maximum power point (MPP) of the PV panel can be easily tracked. The MOSFET's zero-voltage and zero-current switching and diodes are the other countenance of the proposed converter, which improve its efficiency. Additionally, an improved perturb and observe MPP tracking (IP&O MPPT) algorithm is introduced to boost the extracted power of the input PV sources. To validate the performance of this converter, the operation modes principle, steady-state and efficiency survey, and comparison results with other same family converters are carried out. Finally, an experiential prototype is built with 20 V input, 200 V output, power rate of 200 W, and 50 kHz operating frequency to validate the mathematical analysis and effectiveness of the proposed structure. The efficiency of the proposed converter was estimated by over 95% at various power levels.
The objective of this paper is to implement experimentally a maximum power point tracking (MPPT) technique on the Solantro DC-PODX Platform under different operating conditions. The MPPT technique operates in two mode...
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ISBN:
(纸本)9781665435543
The objective of this paper is to implement experimentally a maximum power point tracking (MPPT) technique on the Solantro DC-PODX Platform under different operating conditions. The MPPT technique operates in two modes. The perturb and observation (P&O) MPPT algorithm functions in a local MPPT mode when PV cells receive uniform irradiance. When the PV array is likely to be partially shaded, a global MPPT (GMPPT) subroutine is called to optimize the PV system operation through finding the absolute peak. The method holds two main features, i.e., i) detecting the occurrence of partial shading on a PV panel using the measurement of the sub-strings voltage and ii) fast and reliable tracking of the true maximum power point. The experimental results confirm that the performance of the PV inverter is considerably enhanced as the partial shading condition (PSC) can be properly detected. In addition, the true peak of the PV array under different PSCs can be reliably tracked, yielding a more efficient PV energy harvest.
The photovoltaic system is generally intermittent in nature because of instability in weather such as irradiance and temperature. Therefore it is critical to stabilize the output voltage when a PV module supplies powe...
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ISBN:
(纸本)9781665403795
The photovoltaic system is generally intermittent in nature because of instability in weather such as irradiance and temperature. Therefore it is critical to stabilize the output voltage when a PV module supplies power to wide range of loads. In order to address this issue, boost converter under variable irradiance has been used to extract maximum power from photovoltaic panels applying the conventional perturb and observe maximum power point tracking (MPPT) algorithm in this paper. The unregulated boost converter output considered as input to a buck converter which is controlled by a Proportional Integral controller in order to stabilize the output voltage for different resistive loads. It has been shown that the controller has been successfully capable of regulating the output voltage for wide variation of loads and varying irradiance. The integrated system is built and analyzed in MATLAB/Simulink environment.
The increased demand for electrical energy has driven the development of renewable energy sources. In particular, the conversion of solar energy into electrical energy using photovoltaic (PV) systems has become popula...
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The increased demand for electrical energy has driven the development of renewable energy sources. In particular, the conversion of solar energy into electrical energy using photovoltaic (PV) systems has become popular because of its simplicity and low cost. However, the nonlinear characteristics and power fluctuations due to changes in the temperature and irradiation hinder the maximum utilization of the power with a PV system. Thus, the maximum power point tracking (MPPT) control technique is used to extract the maximum available power from PV arrays. Due to insolation and variations in temperature in a PV system, the conventional MPPT techniques are readily trapped by local maxima to significantly reduce the conversion efficiency. In order to overcome this issue, we developed a novel perturb and observe algorithm based on an adaptive fuzzy PID controller with an improved artificial neural network-based particle swarm optimization method for tracking the maximum power point with high tracking speed as well as maintaining the system's stability. In addition, we used a fuzzy cognitive network to maintain the equilibrium state, which is essential for improving the conversion efficiency. Simulation results and performance evaluations using our proposed method demonstrated its suitability for applications in PV systems. (C) 2019 Elsevier B.V. All rights reserved.
This present paper depicts a robust controller design based on backstepping sliding mode controller (BSMC) for maximum power point tracking (MPPT) of a photovoltaic (PV) system. The investigated PV system is based on ...
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This present paper depicts a robust controller design based on backstepping sliding mode controller (BSMC) for maximum power point tracking (MPPT) of a photovoltaic (PV) system. The investigated PV system is based on a PV module as power source, a DC-DC boost converter and a resistive load. A modified conventional perturb and observe (P&O) algorithm based MPPT control is designed, which presents good performances under constant atmospheric conditions. However, the solar radiation and cell temperature variations present a major effect on the PV output power. Thus, the proposed BSMC controller can allow to the PV system operate around the estimated MPPT under variable atmospheric conditions. Furthermore, the Lyapunov theory is used in order to demonstrate the stability of the PV system with BSMC controller. Moreover, the investigated control approach effectiveness is exhibited by comparing the developed BSMC controller, conventional sliding mode controller (SMC) and modified P&O algorithm. For the proposed BSMC approach, the obtained results with simulation illustrate good efficiency in terms of transition response, tracking error and fast response to atmospheric conditions variation.
Maximum power point tracking (MPPT) is an essential part of a photovoltaic (PV) power generation systems to obtain the possible biggest efficiency. In partial shading conditions (PSCs), distributed MPPT strategy is us...
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Maximum power point tracking (MPPT) is an essential part of a photovoltaic (PV) power generation systems to obtain the possible biggest efficiency. In partial shading conditions (PSCs), distributed MPPT strategy is used to eliminate mismatching cases between PV modules and load. In this study, forward converter-based distributed MPPT approach is presented for small power module-level and submodule-level MPPT applications. First, operation principles of a forward converter are explained for an MPPT application. Then, performance of a forward converter is evaluated by perturb and observe (P&O) algorithm for module-level and submodule-level MPPT systems in MATLAB/Simulink. Simulation results show that in module-level MPPT technique, forward converter cannot track global maximum power point (MPP) in some PSCs. On the other hand, submodule-level MPPT guarantees global MPPT (GMPPT). Average tracking efficiencies are calculated as 71.24% and 95.34% for module-level and submodule-level MPPT, respectively. That is, submodule-level MPPT outperforms module-level MPPT. On the other hand, submodule-level MPPT is more expensive solution since hardware requirements are very high compared with the module-level MPPT strategy.
This paper proposes a modified maximum power point tracking (MPPT) technique for photovoltaic (PV) system using an improved perturb and observe (P&O) with a checking algorithm. The main advantage of this method is...
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This paper proposes a modified maximum power point tracking (MPPT) technique for photovoltaic (PV) system using an improved perturb and observe (P&O) with a checking algorithm. The main advantage of this method is its simplicity and accuracy of the algorithm such that it can even be computed accurately using a low cost microcontroller. The basic idea of this modified P&O is adding a checking algorithm into a modified MO MPPT. This checking algorithm functions to determine the global maximum power by comparing all existed peak points first, before the modified P&O algorithm takes place to identify the voltage at MPP (V-MPP), which is needed to calculate the duty cycle for the boost converter. A simulation using MATLAB/Simulink under partial shading condition has been done to test the effectiveness of the algorithm. The simulation results are satisfactory and show that the improved technique is able to track the PV maximum power during partial shading condition with 100% of tracking efficiency and produce zero ripple at the load side. (C) 2017 Elsevier Ltd. All rights reserved.
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