MCU chip and needs no memory space to save fuzzy rules, and that optimizing factor in the fuzzy inference equation can adjust fuzzy rules on-line automatically to improve systemcontrol effect, which provides the system with an intelligent characteristic. An intelligent control method for MPPT of a photovoltaic system under variable temperature and insolation conditions which uses a fuzzylogic controller applied to a DC– DC converter device is proposed in Cheikh Aı¨t et al. (2007) . Results of this simulation are compared to those obtained by the perturbation and observation controller. A fuzzylogic con- trol (FLC) is proposed in Takun et al. (2011) to control MPPT for a photovoltaic (PV) system; this technique uses the fuzzylogiccontrol to specify the size of incremental current in the current command of MPPT. This paper presents a maximumpowerpoint tracker (MPPT) using FuzzyLogic for a PV sys- tem. The work focused on the well known Perturb and Ob- serve (P&O) algorithm and compared to a designed fuzzylogic controller (FLC). A simulation work dealing with MPPT controller, a DC/DC C´uk converter feeding a load is achieved. The results will show the validity of the proposed FuzzyLogic MPPT in the PVsystem. Most of the performed works in the literature reviews in this point is based on assumed not actual solar radiation data but this paper is used a real data for solar radiation measured by solar radiation and meteorological sta- tion located at National Research Institute of Astronomy and Geophysics Helwan, Cairo, Egypt which is located at latitude 29.87N and longitude 31.30E. The station is over a hill top of about 114 m height above sea level. Example of the daily re- corded measured solar radiation is shown in Fig. 6 .
Because of the increasing of population growth, demand for electricity also increases rapidly. In fact, most power sources obtained today are from fossil fuels that are not renewable and limited. Then, we need renewable energy sources to overcome the crisis in future. Photovoltaic is one of the renewable energy resources in recent years. However, PV modules still have low efficiency due to the atmospheric conditions until right now although the earth receives huge energy from the sun. Therefore, a system that can control and gain maximumpowerpointtracking for the solar array is urgently needed .
Antara sumber tenaga yang boleh diperbaharui, tenaga solar yang digunakan dalam sistem fotovolta merupakan pilihan utama dalam kajian sumber tenaga yang boleh diperbaharui. Disebabkan oleh sistem ini tidak perlu penyelenggaraan, mudah digunakan dan bebas pencemaran, permintaannya meningkat dengan pantas bagi kegunaan perumahan dan industri. Walau bagaimanapun, sel fotovolta menunjukkan kecekapan kuasa yang rendah dalam julat 15-30% dan harga pasaran yang masih mahal; faktor-faktor ini adalah kelemahan utamanya. Disebabkan cirinya tak linear, satu teknik kawalan, dikenali sebagai pengesanan titik kuasa maksimum, perlu bagi sistem fotovolta untuk memastikan kuasa keluaran maximum sentiasa berada pada titik kuasa maksimum. Umumnya, pengesanan titik kuasa maksimum boleh dibahagikan kepada algoritma konvensional dan pintar buatan. Algoritma konvensional yang paling popular adalah usik dan cerap, dan kealiran tambahan. Kelemahan utama kedua-duanya adalah sentiasa gagal untuk mengesan titik kuasa maksimum dan ayunan tinggi berlaku apabila cahaya matahari (sinaran) sering berubah. Antara algoritma pintar buatan yang digunakan dalam pengesanan titik kuasa maksimum adalah rangkaian neural, kawalan logik kabur dan algoritma genetik. Dalam kerja ini, kawalan logik kabur dipilih kerana ia mudah untuk dilaksanakan dan tidak memerlukan model matematik dalam reka bentuknya.
Maximumpower can be obtained from photovoltaic panels, for use by using maximumpowerpointtracking (MPPT) controller . Various approaches have been reported to implement MPPTsuch as perturb andobserve (P&O) method, the incremental conductance method (INC), constant voltage methodand short-circuit current method [4-6]. Using this method the maximumpowerpoint can be found for specified solar irradiation and temperature condition but they displayoscillatory behavior around the maximumpowerpoint under normal operating conditions. Moreover the system will notrespond quickly to rapid changes in temperature or irradiance.
In this paper, sliding mode controller based MPPT algo- rithm has been introduced for the maximumpowertracking of PV systems. By combining the ASMC controller and the incremental conductance method, the MPP is successfully achieved even considering rapidly changing atmosphere. Via simulations, the better performance has been obtained compared to CSMC. Furthermore, the ASMC-based MPPT control method assures better tracking performance and high robustness.
A maximumpowerpoint tracker is a high-efficiency DC-DC converter, which functions as an optimal electrical load for photovoltaic cell, most commonly used for a solar panel or array and converts the power to a voltage or current level which is more suitable to whatever load the system is design to drive. PV cells have a single operating point where the values of current and voltage result in a maximumpower output for the cell. Maximumpowerpoint tracker is basically an electronic system that controls the duty circuit of the converter to enable the photovoltaic module operate at maximum operating power at all condition. The advantages of MPPT regulators are greatest during cloudy or hazy days or cold weather. There are different types of maximumpowerpointtracking methods developed over the years and they are listed below as follows (1) Perturb and observe method, (2)Incremental conductance method, (3) Artificial neutral network method, (4) Fuzzylogic method, (5) Peak powerpoint method, (6) Open circuit voltage method, and (7) Temperature method etc.
The algorithm of a battery charge controller determines the effectiveness of battery charging as well as the PV array utilization, and ultimately the ability of the system to meet the electrical load demands. The most common approaches for charge controllers are the shunt, series, pulse width modulation (PWM) and MPPT charge controllers. The shunt regulator controls the charging of a battery from the PV array by short -circuiting the array internal to the controller. The series controller utilizes some type of control element connected in series between the array and the battery. While this type of controller is commonly used in small PV systems, it is also a practical choice for larger systems due to the current limitations of shunt controllers. The MPPT battery charge controller incorporates a DC-DC converter such that the PV array can operate at the maximumpowerpoint at the prevailing solar irradiance. The structure of battery charge controllers depends on the type of the controller. In the series and shunt controllers, it simply consists of a switching element, such as a relay that is switched on/off based on the value of a predefined set point. In a PWM and MPPT control lers, the circuits are more sophisticated. In PWM generator circuits, microcontrollers are needed in order to drive the switches of a DC–DC converter while MPPT controller consists of a controller that manages the maximumpowerpointtracking process and DC-DC converter . In this paper, a DC-DC SEPIC converter is selected and has been employed for standalone PVsystem application. Using this converter, the PVsystem is able to execute good MPPT and charging control performance.
also it is known that P&O algorithm can be jumbled during those time intervals characterized by rapidly changing the environmental conditions. This paper it is shown that, to limit the negative effects related to above drawbacks, the P&O MPPT parameters must be modified to the dynamic behavior of specific converter adopted. A theoretical analysis permitting optimal choice of such parameters is carried out. For large Power Generation System, probability for partially shaded condition to occur is high. Under Partially shaded condition(PSC), the P-V curve of PVsystem has multiple peaks, which reduces effectiveness of conventional maximumpowerpointtracking methods. In this paper, particle swarm optimization (PSO) based MPPT algorithm for PVsystem operating under PSC is proposed. Standard version of PSO is modified to meet practical consideration of PGS operating under PSC. Problem formulation, design method and parameter setting method which takes hardware limitation into account are styled and explained in detail. The proposed method claims the advantages such as very easy to implement, pvsystem independent and has high maximumpowerpointtracking efficiency. To confirm correctness of the proposed method simulation results, and experimental results of 500W PVsystem will be provided to demonstrate effectiveness of proposed technique.
In this study, the characteristics of a PV module (Kyocera KD210GH) were mathematically modeled and simulated using MATLAB simulation tool. Then, the proposed MPPT algorithm and dc-dc boost converter were designed and developed in the same tool. Simulation results are presented to validate performance of the algorithm under different irradiation schemes, and to compare with the results obtained from conventional algorithm. Further experimental setup was carried out for comparative evaluation and the MPPT algorithm was implemented to performance verification of the algorithm by using digital signal processor (TMS320F28335).
ABSTRACT: In PVsystempower available at the output of solar cell keeps on changing with changing irradiation, temperature and load because solar cell exhibits nonlinear V-I characteristic therefore MPP of solar cell varies. Maximumpowerpointtracking therefore plays an important role in optimizing solar energy efficiency. In this paper two intelligent control technique – Fuzzylogic and Artificial Neural Network are use for MPPT of PV array. Fuzzylogic does not need the knowledge of exact model of the system and uses heuristic reasoning based on experience to deal with this nonlinearity of PV arrays. The proposed ANN is trained with PV output current, voltage to estimate the duty cycle of dc-dc boost converter and their by track MPP of PV arrays. A conventional IC algorithm is compared to these intelligent control algorithm on the basis of settling time, efficiency, transient tracking time, steady state oscillation, dynamic behaviour. MATLAB/SIMULINK is use to design three phase grid connected PVsystem consisting of 100kW PV array, DC-DC boost converter, three phase three level diode clamped inverter along with synchronous reference frame control strategy connected to utility grid via a three phase coupling transformer.
Several MPPT techniques have been discussed in this paper. From this, it is clear that it can be very difficult to choose the best; each MPPT method has its own advantages and disadvantages and the choice is highly applica- tion dependent. For example, solar vehicles require fast convergence to the MPP; in this case good options are fuzzylogiccontrol, and neural network. In orbital stations and space satellites, which involve large cost, the performance and reliability of the MPPT are most important. The tracker must be able to continuously track the true MPP in the minimum amount of time and should not require periodic tuning. In this case, the appropriate methods are O & P/Hill-climbing and IC . When using solar panels in residential locations, the objective is to reduce the payback time. To do so, it is necessary to constantly and quickly track the maximumpowerpoint. Furthermore, the MPPT should be capable of minimising the ripple around the MPP. Therefore, the two stage IC and optimised P & O methods are suitable.
The inductor in the boost converter possibly produces the ripples in the input current. This can be minimized with two- phase interleaved boost converter. The interleaved boost converter has its high power density and fast dynamic response by operating at 180 o out of phase. This causes the ripple currents to cancel out. The proposed system is controlled by the fuzzylogic controller (FLC) that produces the desired gate pulses for the switches to operate at desired time intervals for the switching sequences.
PVpower systems are one of today’s fastest growing renewable energy technologies, providing more secure power sources and pollution free electric supplies. Unfortunately, PV systems have high fabrication cost and low energy conversion efficiency. Since the PV electricity is expensive compared to the electricity from the utility grid, utilization of maximumPVsystem output power is desired. Therefore, the PVsystem should be operating at their maximum output power (MPP) in any environmental conditions (1) . The system’s operating point is at the intersection of the I-V curves of the PVsystem and load, when a PVsystem is directly connected to a load. The MPP of PVsystem is not attained most of the time. The problem is overcome by using a MPPT algorithm which maintains the PVsystem operating point at the MPP. There are several MPPT continuously searches algorithms that have been proposed in the literature which uses different characteristics of solar panels and the location of the MPP, including perturb-and-observe method, open- and short- circuit method, incremental conductance algorithm, fuzzy
Abstract- How to design a grid connected photovoltaic system, including modeling of photovoltaic cells DC-DC Ćuk design. The maximumpowerpointtracking is superior other techniques. Maximumpowerpointtracking is implemented in grid-connected photovoltaic systembased on Perturb and Observation (P&O) algorithm. sliding mode controller is best for maximumpowerpointtrackingsystem. Due to non-linear nature of the system, the use of sliding mode method can sustain the stability of the converter in wide range of variations in radiation, load, sliding mode method, only input voltage and capacitive filter current are utilized as a feedback and the design process is completed without the converter model inclusion. The effectiveness of the proposed photovoltaic system is evaluated by simulations conducted on MATLAB/SIMULINK.
consuming. The method in  is based on IC and sampling is done in the PV characteristic curve of the array. But it limits the search area as in  and also requires high sampling number. In references [16-21] the MPPT is studied as an optimization problem +using PSO method, simulated annealing method and colony of flashing fire flies method. These methods are successful but the sampling number used is so high. It is known from references [22,23] that boost converters undergo some transients to settle the PV array. In [1, 19] a typical PSO method is used which has the low speed. In  the PSO method is modified to improve in complexity and speed. In  a method based on the firefly algorithm is proposed. This method has the better speed and efficiency compared to the PSO method. The main purpose of this paper is to study and compare two maximumpowerpointtracking (MPPT) methods in a photovoltaic simulationsystem. The methods used are Incremental Conductance method and FuzzyLogic Controller.
A successful MPPT-PVsystem design must take into consideration a few requirements. Stability is the most fundamental design requirement of a dynamic controlsystem. In PVpower systems, the switching mode converters are nonlinear systems and the output characteristics of solar array are also nonlinear. Therefore, stability is a critical factor to evaluate a PV MPPT control systems dealing with non-linearity. Besides this, in MPPT control systems, a good dynamic response is desirable for the fast tracking requirement. A good MPPT control algorithm needs to respond quickly to rapidly changing atmospheric conditions like temperature and illumination and track the maximumpower points quickly. It is also important to design a MPPT controlsystem robust to any kind of disturbances. The disturbances can arise from various sources, one of the most common problems is that the PV modules manufactured by different technologies
Today photovoltaic (PV) systems are becoming more and more popular with increase of energy demand and there is also a great environmental pollution around the world due to fossils and oxides. Solar energy which is free and abundant in most parts of world has proven to be economical source of energy in many applications . The energy that the earth receives from the sun is so enormous and so lasting that the total energy consumed annually by the entire world is supplied in as short a time as half an hour. The sun is a clean and renewable energy source, which produces neither green house effect gas nor toxic waste through its utilization. It can withstand severe weather conditions, including cloudy weather. The watt peak price is decreased since the seventies, this leads to large scale promising areas. It does not have any moving parts and no materials consumed or emitted. Unfortunately, this system
In this study, FLC has been developed to track the maximumpowerpoint of PVsystem. PV panel, boost converter with FLC connected to a resistive load has been simulated using Matlab/Simulink. Simulation results have been com- pared to nominal power values. The proposed system showed its ability to reach MMP under uniform irradiation, sudden changes of irradiation, and partial shading. Simulation results have shown that using FLC has great advantages over conventional methods. It is found that Fuzzy controller always finds the global MPP. It is found that fuzzylogic systems are easily implemented with minimal oscillations with fast convergence around the desired MPP.
The open circuit P-V, P-I, I-V curves we obtained from the simulation of the PV array designed in MATLAB environment explains in detail its dependence on the irradiation levels and temperatures. The entire energy conversion system has been designed in MATLB-SIMULINK environment. The various values of the voltage and current obtained have been plotted in the open circuit I-V curves of the PV array at insolation levels of 100 mW/m2 and 80 mW/m2. Then the sliding-mode observer for the estimation of solar array current in the PVsystem has been proposed. The sliding-mode observer is constructed from the state equation of the system, and the convergence of the error system is proved using equivalent control concept. A switched system model was introduced to design maximum peak powertracking controller for PV cells based on the sliding mode control approach, where