MPPT

Variations in load and temperature can cause a thermoelectric generator (TEG) to operate at a voltage that does not produce the maximum possible power for a given temperature difference. Therefore a maximum power point tracker (MPPT) is used to force the generator to a voltage that produces maximum power. This paper presents a comparative simulation study of two important MPPT algorithms specifically perturb and observe and incremental conductance. The Matlab Simulink environment is used to analyze and interpret the simulation results of these algorithms, and therefore show the performance and limitations of each algorithm. As a result, the Incremental conductance method has shown promise as a suitable MPPT algorithm for a TEG subjected to steady state conditions.

In this paper, investigated advantages of Electric Spring with Back to Back converter in an Hybrid system having solar and wind as energy sources and battery as storage device. PMSG is used for conversion in wind generating system. The characteristic of the electric spring in providing fast reactive power compensation and voltage and frequency stability is found to be highly useful in recovering PMSGs when un stabilized event due to weather conditions occurs. An effective control scheme is developed for Back to Back to converter to achieve stability even during severe weather conditions. Proposed converter in hybrid system is verified by simulation using MATLAB/SIMULINK. The results show that Electric Spring Back to Back converter is efficiently stabilizing the voltage and frequency and compensating the reactive power

Thermoelectric generation technology is considered to be one of the viable methods to convert waste heat energy directly into electricity. The utilization of this technology has been impeded due to low energy conversion efficiency. This paper aims to improve the energy conversion efficiency of the thermoelectric generator (TEG) model with a novel maximum power point tracking (MPPT) technique. A variable fractional order fuzzy logic controller (VFOFLC)-based MPPT technique is proposed in the present work in which the operating point of the TEG is moved quickly towards an optimal position to increase the energy harvesting. The fraction order term α, introduced in the MPPT algorithm, will expand or contract the input domain of the fuzzy logic controller (FLC to shorten the tracking time and maintain a steady-state output around the maximum power point (MPP). The performance of the proposed MPPT technique was verified with the TEG model by simulation using MATLAB /SIMULINK software. Then, the overall performance of the VFOFLC-based MPPT technique was analyzed and compared with Perturb and observe (P&O) and incremental resistance (INR)-based MPPT techniques. The obtained results confirm that the proposed MPPT technique can improve the energy conversion efficiency of the TEG by harvesting the maximum power within a shorter time and maintaining a steady-state output when compared to other techniques.

This paper proposes a compact Thévenin model for a rectenna. This model is then applied to design a high-efficiency radio frequency harvester with a maximum power point tracker (MPPT). The rectenna under study consists of an L-matching network and a half-wave rectifier. The derived model is simpler and more compact than those suggested so far in the literature and includes explicit expressions of the Thévenin voltage (Voc) and resistance and of the power efficiency related with the parameters of the rectenna. The rectenna was implemented and characterized from −30 to −10 dBm at 808 MHz. Experimental results agree with the proposed model, showing a linear current–voltage relationship as well as a maximum efficiency at Voc/2, in particular 60% at −10 dBm, which is a remarkable value. An MPPT was also used at the rectenna output in order to automatically work at the maximum efficiency point, with an overall efficiency near 50% at −10 dBm. Further tests were performed using a nearby tra...

This paper analyzes two maximum power point
tracking (MPPT) converter topologies that are part of an
interface converter for the integration of photovoltaics (PV) in
the grid. Two different MPPT converter topologies (boost
converter and quasi-Z-Source (qZS) converter) were selected and compared. Theoretical comparison includes an analysis of
regulations for obtaining continuous source current and
comparison of necessary parameters of the reactive elements of the systems.
270 W experimental prototypes of both converters were built
and experimentally compared. Theoretical and experimental
efficiency estimation is proposed and discussed. Also, the losses in diodes and MOSFETS are evaluated taking into account technical data from datasheets

The control and operation of electronic systems
relies and depends on the availability of  the  power supply.
Rechargeable batteries have been more pervasively used as
the energy storage and power source for various electrical and electronic systems and devices, such as communication
systems, electronic devices, renewable power systems, electric vehicles, etc. However, the rechargeable batteries are
subjected to the availability of the external power source when it is drained out. Because of the concern of battery life,
environmental pollution and a possible energy crisis, the
renewable solar energy has received an increasing attention
in recent years. A fuzzy logic control based grid tied
uninterruptible power supply integrating renewable solar
energy can be used for electrical and electronic systems to
produce power generation. This paper presents the design and implementation of fuzzy logic control based grid tied
uninterruptible power supply integrating the renewable  solar power energy system. The uninterruptible power supply (UPS) system is characterized by the rechargeable battery that is connected  with  the Photovoltaic Panel through the DC/DC converter,  the  utility AC through the AC/DC  converter  and the load is connected through the DC/AC converter. The whole operation is controlled by the fuzzy logic algorithm. A complete hardware prototype system model of the fuzzy logic control based  on the  grid tied uninterruptible power supply integrating with the  renewable solar energy is designed and implemented. The operation and effectiveness of the proposed system is  then  demonstrated by  the  actual and  real-time implementation of  the  fuzzy logic control grid tied operation 
uninterruptible power supply integrating renewable  solar
energy connected to the rechargeable battery bank and a PIC
microcontroller platform for fuzzy logic control and operation.

Thermoelectric generation technology is considered to be one of the viable methods to convert waste heat energy directly into electricity. The utilization of this technology has been impeded due to low energy conversion efficiency. This paper aims to improve the energy conversion efficiency of the thermoelectric generator (TEG) model with a novel maximum power point tracking (MPPT) technique. A variable fractional order fuzzy logic controller (VFOFLC)-based MPPT technique is proposed in the present work in which the operating point of the TEG is moved quickly towards an optimal position to increase the energy harvesting. The fraction order term α, introduced in the MPPT algorithm, will expand or contract the input domain of the fuzzy logic controller (FLC to shorten the tracking time and maintain a steady-state output around the maximum power point (MPP). The performance of the proposed MPPT technique was verified with the TEG model by simulation using MATLAB /SIMULINK software. The...

Thermoelectric generation technology is considered to be one of the viable methods to convert waste heat energy directly into electricity. The utilization of this technology has been impeded due to low energy conversion efficiency. This paper aims to improve the energy conversion efficiency of the thermoelectric generator (TEG) model with a novel maximum power point tracking (MPPT) technique. A variable fractional order fuzzy logic controller (VFOFLC)-based MPPT technique is proposed in the present work in which the operating point of the TEG is moved quickly towards an optimal position to increase the energy harvesting. The fraction order term α, introduced in the MPPT algorithm, will expand or contract the input domain of the fuzzy logic controller (FLC to shorten the tracking time and maintain a steady-state output around the maximum power point (MPP). The performance of the proposed MPPT technique was verified with the TEG model by simulation using MATLAB /SIMULINK software. The...

The demand of solar energy has increased rapidly in this decade. This is due to the advantages of the energy compared to other form of sources. The solar energy conversion system is very interesting alternative on supplement the electric system generation, due to the persistent cost reduction of the overall system and cleaner power generation. To obtain a stable voltage from an input supply (PV cells) that is higher and lower than the output, a high efficiency and minimum ripple DC-DC converter required in the system for residential power. Buck-boost converters make it possible to efficiently convert a DC voltage to either a lower or higher voltage. Buck-boost converters are especially useful for PV maximum power tracking purposes, where the objective is to draw maximum possible power from solar panels at all times, regardless of the load.

Maximizing the power point tracking of photovoltaic
systems is currently the purpose of several researches in the
context of renewable energies improvement. In this work we
optimize and enhance the maximum power point tracking
algorithm based on fuzzy logic controller. Our approach focuses
on determining the maximum power point in a minimal time in
order to get the lowest possible energy loss. The fuzzy logic
controller presented in this work provide fast response and good
performance against the climatic and load change and uses
directly the DC/DC converter duty cycle as a control parameter.
After establishing our algorithm, we have performed a
comparative study with the classical algorithm used most perturb
and observe in various operating conditions. The simulation
results using MATLAB/Simulink show that fuzzy logic controller
provides better tracking compared to Perturb and observe despite
the climatic change (solar insolation and temperature).

With the increasing demand of power and energy, energy conservation and use of renewable resources have become a crucial necessity. Solar energy will become the ultimate and prime source of energy in near future. Therefore, highly efficient and low energy consuming solar-powered equipment and applications will soon be a major requirement. In this paper, solar charge controller using Maximum Power Point Tracking (MPPT) and Pulse Width Modulation (PWM) have been analyzed and compared, which is needed in all solar powered systems that utilize batteries. Its role is to regulate the power going from the solar panel to the batteries. Most of the modern charge controllers include PWM and MPPT. These charge controllers are designed such that the solar battery gets recharged quickly and does not get over discharged, thereby ensuring the prolonged lifespan of the battery.

With the increasing demand of power and energy, energy conservation and use of renewable resources have become a crucial necessity. Solar energy will become the ultimate and prime source of energy in near future. Therefore, highly efficient and low energy consuming solar-powered equipment and applications will soon be a major requirement. In this paper, solar charge controller using Maximum Power Point Tracking (MPPT) and Pulse Width Modulation (PWM) have been analyzed and compared, which is needed in all solar powered systems that utilize batteries. Its role is to regulate the power going from the solar panel to the batteries. Most of the modern charge controllers include PWM and MPPT. These charge controllers are designed such that the solar battery gets recharged quickly and does not get over discharged, thereby ensuring the prolonged lifespan of the battery.

This project proposes an electric vehicle charging station composed of photovoltaic (PV) array, DC-DC converter provided with MPPT control, energy storage unit, DC charger and inverter. The plug-in hybrid electric vehicles(PHEVs) and electric vehicles (EVs) represent an important step in solving environmental problems and emission of greenhouse gases. The integration of renewable energy and public grid utility is increasing and its associated energy management system makes attention. This project focuses on PV grid-connected system control strategy, which allows the feeding of a Battery Electric Vehicle (BEV). The system is presented as several subsystems: PV array, DC-DC converter provided with MPPT control, energy storage unit, DC charger and inverter, electric vehicle as load and public grid utility

This paper presents the modeling of wind energy systems using MATLAB Simulink. The model considers the MPPT (Maximum Power Point Tracking) technique to track the maximum power that could be extracted from the wind energy, due the non-linear characteristic of the wind turbine. The model consists of wind generation model, converter model (DC-DC converter), and MPPT controller. The main contribution of our work is in the model of DC-DC converter (buck converter) which is developed in rather details, which allows the MPPT controller output (duty cycle) adjusts the voltage input of the converter to track the maximum power point of the wind generator. The simulation results show that the developed model complies with the theoretical one. Further the MPPT control shows a higher power output compared to the system without MPPT.

The aim of this study is to conduct a literature review of the different Maximum Power Point Tracking techniques (MPPT) for photovoltaic systems, and identify the most suitable method for a domestic (low power) photovoltaic installation.
The characteristics of each method are identified and classified into two main groups, namely: iterative methods, and analytical methods. The advantages of each method in relation to the others are discussed, under which conditions they have a better performance and which one allows to extract the most power from the photovoltaic system in all the different scenarios that may arise. Then, two of the most representative analytical methods are chosen, along with the most representative of the iterative methods as counterpart. These are tested by two types of simulations, consisting of changes in atmospheric conditions. Firstly, a simulation of a step perturbation (irradiance and temperature) is run and then a simulation of a continuous change with a ramp perturbation (temperature), based on the European Standard EN 50530. This is done in the simulation software, PLECS from Plexim.
Finally, the results from the simulations are compared, and according to the efficiency presented, the advantages and disadvantages, and the conditions under which they perform better, the most suitable MPPT method for a domestic photovoltaic system is chosen, which turns out to be the Temperature Gradient method. This method has the highest efficiency among the simulated MPPT methods, and its increased complexity is only one extra temperature sensor.
A secondary objective is to evaluate the simulation software PLECS, in terms of its ability to simulate photovoltaic systems. The software turns out to be deficient in this matter due to the lack of a photovoltaic module block. So an alternative method has to be used, and it depends on other software for this.

An improved algorithm for MTPA (Maximum Torque Per Ampere) and Field Weakening operation which is suitable for implementation with Field Oriented Control, has been proposed for the Synchronous Reluctance motor (SynRel) for high dynamic performance. The proposed method overcomes the problem of excessive current flow into the machine while generating the d-axis and q-axis current commands independently. At the same time to operate the inverter in the linear modulation region (0≤m≤1) to minimize the output torque ripple. The proposed method helps to attain MTPA operation below the base speed to operate with the rated load and a fast speed response in Field Weakening mode. The validity and efficacy of the proposed algorithm is verified by simulation in MATLAB and SIMULINK.

Distribution generation based on sustainable has appeared as a demanding part
of research between investigators to conflict the issue of maximizing the pressure. In
case of microgrids of DG basis, suspended loads and generators are in close level in a
bid to assist consecutive power supply. In DG systems electronic interfacing originate
critical power quality issues of harmonics in generation and compensation of reactive
power which make the distribution of power system inferior. The compensation of
Reactive power is necessary to support an adequate level of power standard in
microgrids due to tightly coupled distribution with generation. So, many experiments
have been claimed in this research area for reduction of these agitated hurdles in the
enlarging microgrid system. Modern fashions are around attainment of devices used
for different task to tackle various standardization of power problems concurrently. So
this paper presents an analysis of a microgrid, its designing and challenges in
standardization of power problems accepted in the microgrid, analyzing compensation
methods reported by previous investigators utilizing different techniques of control,
algorithms, and devices.

Several algorithms have been offered to track the Maximum Power Point when we have one maximum power point. Moreover, fuzzy control and neural was utilized to track the Maximum Power Point when we have multi-peaks power points. In this paper, we will propose an improved Maximum Power Point tracking method for the photovoltaic system utilizing a modified PSO algorithm. The main advantage of the method is the decreasing of the steady state oscillation (to practically zero) once the Maximum Power Point is located. moreover, the proposed method has the ability to track the Maximum Power Point for the extreme environmental condition that cause the presence of maximum multi-power points, for example, partial shading condition and large fluctuations of insolation. To evaluate the effectiveness of the proposed method, MATLAB simulations are carried out under very challenging circumstance, namely step changes in irradiance, step changes in load, and partial shading of the Photovoltaic array. Finally, its performance is compared with the perturbation and observation" and fuzzy logic results for the single peak, and the neural-fuzzy control results for the multi-peaks.

This paper describes the Grid connected solar photovoltaique system using DC-DC boost converter and the DC/AC inverter (VSC) to supplies electric power to the utility grid. The model contains a representation of the main components of the system that are two solar arrays of 100 kW, boost converter and the grid side inverter. The paper starts with a system description, in this part we have given a definition and a short overview of every component used in this system and they are taken separately. The PV cell model is easy, accurate, and takes external temperature and solar radiation into consideration. It also proposes a maximum power point tracking (MPPT) algorithm. The algorithm incorporated in a DC/DC converter is used to track the maximum power of PV cell. Finally, the DC/AC inverter (VSC) of three- level is used to regulate the ouput voltage of DC/DC converter and connects the PV array to the grid. Simulation results show how a solar radiation’s change can affect the power output of any PV system, also they show the control performance and dynamic behavior of the grid connected photovoltaic system.

One of  the  advanced  power  applications  using  energy  storage  is  the integration  of  energy  storage  technologies  with  VSC-based  FACTS controllers.  With  the  support  of  energy  storage  device,  FACTS  controllers will have the ability to exchange active power or energy with the ac network in  steady  state.  This  paper  discusses  the  impact  of  Static  Synchronous Compensator  incorporating  energy  storage  device  (STATCOM-ES)  on subsynchronous resonance (SSR). It also proposes the design of an auxiliary SSR    damping    controller    (SSDC)    for    STATCOM-ES    to    damp    the subsynchronous  oscillations  which  the system  is  undergoing  because  of  a series  capacitor  in  the  transmission  system.  The  system  under  consideration is  IEEE  FBM  which  is  modified  to  incorporate  STATCOM-ES  at  the electrical  midpoint.  The  investigation  of  SSR  characteristics  when  a STATCOM -ES operating in bus voltage regulation mode is carried out by eigenvalue  and  damping  torque  analysis.  Transient  analysis  based  on  the nonlinear  model  is  also  performed  to  validate  the  results  obtained  by conventional methods.

In a distributed generation system, divers renewable agents are connected to the low voltage 3 phase utility grid by an inverter which is used as power condition and must assurance the higher efficiency of the renewable agent. To achieve this level of efficiency, a unitary power factor between the utility grid voltages and the inverter currents is necessary, and a synchronization algorithm is required for the perfect synchronization between the 3-phase utility grid and the renewable agent. The aim of this paper is to present the optimization of the performance of a Synchronization controller for a 3-phase photovoltaic grid-connected system, assessing its accuracy under different conditions and studying their drawbacks and advantages. A grid connected photovoltaic system with a nominal power of 5 kW is used so as to assess the behavior of the synchronization algorithm when the 3 phase utility grid is affected by some disturbances such as voltage unbalances.

This paper envisages to identify an optimal topology of DC-DC converter for the solar pump application, by comparing the performance indices of the three advanced non-isolated converters namely Landsman converter, Luo converter and Zeta converter. The identified best topology of the non-isolated DC-DC converter, which basically operates in the mode of buck-boost converters cascaded to a three phase voltage source inverter (VSI), which is connected to a permanent magnet brushless DC (PMBLDC) motor. The whole system is front ended to a PV panel. In order to obtain the maximum power transfer to the load, a popular maximum power point tracking (MPPT) technique, Perturb and Observe (P&O) has been implemented. The whole system is simulated under the environment of PSIM.

When the GPV is under partial shading, several peaks appear in the characteristic P-V, namely a GMP and one or more local maximums. The classical algorithm 'P&O' MPPT cannot converge on the GMP for low irradiation values and is trapped by tracking down a LMP so making the algorithm ineffective making the algorithm ineffective, in this case under 200 W/m². An alternative objective function is developed to optimize the performance of the FLC by selecting the appropriate gains using PSO. In this simulation the GPV is composed of one hundred modules grouped parallel series (10x10) and subjected to partial shading. The proposed FLC provides better performance for GMP tracking for the chosen shade configuration selected.

This research presents a new scheme to extract the maximal available power from a wind turbine employing a doubly fed induction generator (DFIG). This scheme is developed from the wind turbine's MPPT-curve. Furthermore, we propose control laws for the rotor and grid side-converters. The stability of the proposed maximum available power method and the control laws are proved mathematically upon Lyapunov's stability criterion. Their efficiency is tested through the simulations of a DFIG wind turbine in Matlab/Simulink. Simulation results are analyzed and compared with that using a conventional scheme. Thanks to the suggested scheme, the wind turbine can track its maximum power point better and the electric energy output is higher comparing with that using the conventional scheme. Furthermore, by the suggested controllers, the rotor speed and current of the DFIG converged to their desired values. In other words, the wind turbine can achieve stable operations by the suggested control laws. Chieu district, Danang city, Vietnam 84-988983127 pdchung@dut.udn.vn 1. INTRODUCTION The maximum power generation of a wind turbine has been interested in several decades and many algorithms have been suggested. According to [1], previous maximum power point tracking (MPPT) methods can be listed into three groups including indirect power controller, direct power controller, and others. The indirect power controller which aims to maximize mechanical power by using tip-speed ratio [2], [3], optimal torque [4], and power signal feedback MPPT algorithm [5] is simplicity and only allows the wind turbine to track its MPPT-curve quickly when a wind speed measurement is precise and instantaneous. In the case of an unavailable wind measurement, a wind turbine using the indirect power controller fails to track its maximum power point quickly and accurately [6], [7]. The direct power controller which maximizes electric power by using the perturbation and observation (P&O) algorithm such as: Hill climb search [8], incremental conductance [9], optimal-relation based MPPT algorithm [10], [11], and hybrid MPPT algorithm [12] does not require any wind turbine knowledge and available anemometer. Unfortunately , a wind turbine using the direct power controller cannot track its maximum power because this controller cannot recognize instantaneously the variation in wind speed. Until now, this controller has been implemented to adjust the voltage and current of DC circuit in a permanent magnetic synchronous generator wind turbine. The last group is developed based on soft computing techniques like Fuzzy [13] and Neural network [14]. A wind turbine using these methods only has a good performance when the full information of the wind turbine is available. However, these methods are complexity and large memory requirement. Hence, a new MPPT scheme for DFIG wind turbines should be researched. To control the generator-wind turbine, proportional-integral (PI) control is normally implemented because of its simplicity [7], [15], [16]. However, by using the PI control, we cannot guarantee the wind turbine system will become stable operation [17], [18]. Recently, control laws based on sliding mode were suggested for rotor speed adjustment [19], [20]. However, these control laws require an available wind speed measurement. Hence, we need