Design and Implementation of Takagi-Sugeno Fuzzy Tracking Control for a DC-DC Buck Converter

This paper presents the design and implementation of a Takagi-Sugeno (T-S) fuzzy controller for a DC-DC buck converter using Arduino board. The proposed fuzzy controller is able to pilot the states of the buck converter to track a reference model. The T-S fuzzy model is employed, firstly, to represent exactly the dynamics of the nonlinear buck converter system, and then the considered controller is designed on the basis of a concept called Virtual Desired Variables (VDVs). In this case, a two-stage design procedure is developed: i) determine the reference model according to the desired output voltage, ii) determine the fuzzy controller gains by solving a set of Linear Matrix Inequalities (LMIs). A digital implementation of the proposed T-S fuzzy controller is carried out using the ATmega328P-based Microcontroller of the Arduino Uno board. Simulations and experimental results demonstrate the validity and effectiveness of the proposed control scheme

T-S Controllers For Photovoltaic-Grid Connected System Through DC-DC Boost Converter and Three Phase Inverter

Ce document présente deux contrôleurs flous TS en ligne pour contrôler l'extraction de puissance optimale et son transfert du système PV via deux convertisseurs statiques vers le réseau public. Le premier contrôleur est appliqué sur le convertisseur élévateur pour calculer, à chaque instant, le rapport cyclique permettant de suivre le point de puissance maximale du panneau sous les variations climatiques et d'atteindre un rendement élevé pour la récolte d'énergie solaire. Alors que le second ajuste les états de commutation des branches de l'onduleur triphasé à deux niveauxtransistors pour un transfert maximal de la puissance active produite par le panneau vers le réseau de distribution avec compensation de puissance réactive lors de l'établissement de la synchronisation.Après présentation de la structure du système de connexion au réseau et modélisation mathématique des convertisseurs côté PV et côté réseau, les contrôleurs flous TS sont détaillés. La synthèse de ces contrôleurs est basée sur la subdivision de l'espace d'états du système non linéaire à contrôler en un ensemble de sous-systèmes linéaires. Pour assurer le rejet des perturbations et garantir la stabilité du contrôleur flou,  Le critère et la fonction de stabilité quadratique de Lyapunov sont considérés. Les gains du contrôleur sont calculés en utilisant la solution d'inégalité de matrice linéaire (LMI). Les résultats de la simulation numérique sur l'environnement Matlab-Simulink montrent l'efficacité et les performances des contrôleurs proposés

Modelling and optimisation of solar voltaic system using fuzzy logic

There is considerable increase in residential solar grid connected installations with many advantages offered by solar energy. As more solar panels are connected to grid, the Solar Inverter between solar panels and grid have to perform at optimum levels. Modern Inverters consist of DC-DC Converter and DC-AC Inverter. One problem associated with Inverter design is voltage fluctuation, this defect lies in the DC-DC converter Maximum power tracking (MPPT) algorithms responsible for extracting maximum power from the solar panels. The defect is due to large sampling number required for conventional MPPT algorithm. This thesis has proposed a new MPPT algorithm based on Mamdani Fuzzy logic. In research we use 5 parameter one diode model for solar cell modelling. The P-V/I-V characteristics curve is generated. The P-V characteristics curves sectioned and input membership and output membership functions is created. And unique fuzzy rules is used to optimize fuzzy controller output. Mamdani Fuzzy logic algorithm is compared to traditional PI controller hill climbing method. When small sampling number is used hill climbing method response is slow and good at tracking. When big sampling number is used hill climbing method response is fast and not good at tracking. The voltage also fluctuates when sampling number is big. Fuzzy logic provides a compromised solution with best response time and moderate tracking accuracy compared to hill climbing method. Fuzzy Logic based DC-DC converter together with PLL and Recursive Discrete Fourier Transform (RDFT) DC-AC inverter synchronization algorithm is employed and simulated in matlab. The MPPT simulation is conducted for a realistic 2.5KW solar panels in a 8 x 2 Matrix. In addition the MPPT algorithm is analyzed to see if it performs under power quality and voltage level tolerance of utility grid requirements. The Fuzzy Logic MPPT is excellent at tracking power. When temperature is fixed and irradiance is varied, the maximum tracking error is 5.2% in all scenarios with one exception. When irradiance is fixed and temperature varied, the maximum tracking error is 1.98%. Furthermore the Fuzzy Logic MPPT meets the power quality and voltage level tolerance requirements of utility grid for irradiance over 600 W/m2. Power quality and voltage level tolerance requirements for irradiance under 600 W/m2 is not critical as this is outside twilight conditions. Out of all the Synchronization algorithm identified in this Thesis, RDFT achieves synchronization very quickly and in addition it suppresses harmonics and noise. The possibility of future study to extend MPPT is also briefly discussed. The extension of future study is using Takagi-Sugeno fuzzy logic. Takagi-Sugeno uses more sophisticated inference and rule evaluation mathematics

Advanced Mathematics and Computational Applications in Control Systems Engineering

Control system engineering is a multidisciplinary discipline that applies automatic control theory to design systems with desired behaviors in control environments. Automatic control theory has played a vital role in the advancement of engineering and science. It has become an essential and integral part of modern industrial and manufacturing processes. Today, the requirements for control precision have increased, and real systems have become more complex. In control engineering and all other engineering disciplines, the impact of advanced mathematical and computational methods is rapidly increasing. Advanced mathematical methods are needed because real-world control systems need to comply with several conditions related to product quality and safety constraints that have to be taken into account in the problem formulation. Conversely, the increment in mathematical complexity has an impact on the computational aspects related to numerical simulation and practical implementation of the algorithms, where a balance must also be maintained between implementation costs and the performance of the control system. This book is a comprehensive set of articles reflecting recent advances in developing and applying advanced mathematics and computational applications in control system engineering

Energy from organic sources

Elevated environmental awareness and exhaustion of resources are leading to develop substitute fuel from renewable resources that can be environmentally friendly. Bio-diesel fuel is a substitute to petrol base fuels currently being obtained from vegetable oils, animal fat, utilized oils from restaurants etc. Pet animal fats represent large wastes in tanneries. With a high energetically worth, animal fats may make up an energetical source with significant capital opportunities as raw substance (used with high precautionary measure) or also as oils acquired from ester interchange with alcohol (biodiesel) with higher facets being used as fuel at diesel engines

Simulation and Implementation of a Modified ANFIS MPPT Technique

The maximum power point tracking (MPPT) algorithms ensure optimal operation of a photovoltaic (PV) system to extract the maximum PV power, regardless of the climatic conditions. This paper exposes the study, design, simulation and implementation of a modified advanced neural fuzzy inference system (ANFIS) MPPT algorithm based on fuzzy data for a PV system. The studied system includes a PV array, a DC/DC buck converter, the ANFIS controller, a proportional-integral (PI) controller, and a load. The simulation and experimental tests are carried out with the MATLAB/Simulink software and LabVIEW, respectively. Moreover, the obtained results are compared with previously published results by incremental conductance (IC) and fuzzy logic (FL) algorithms under different climatic conditions of irradiation and temperature. The results show that the proposed ANFIS algorithm is able to track the maximum power point for varying climatic conditions. Furthermore, the comparison analysis reveals that the PV system using ANFIS algorithm has more efficient and better dynamic response than FL and IC

TS fuzzy approach for modeling, analysis and design of non-smooth dynamical systems

There has been growing interest in the past two decades in studying the physical model of dynamical systems that can be described by nonlinear, non-smooth differential equations, i.e. non-smooth dynamical systems. These systems exhibit more colourful and complex dynamics compared to their smooth counterparts; however, their qualitative analysis and design are not yet fully developed and still open to exploration. At the same time, Takagi-Sugeno (TS) fuzzy systems have been shown to have a great ability to represent a large class of nonlinear systems and approximate their inherent uncertainties. This thesis explores an area of TS fuzzy systems that have not been considered before; that is, modelling, stability analysis and design for non-smooth dynamical systems. TS fuzzy model structures capable of representing or approximating the essential dis- continuous dynamics of non-smooth systems are proposed in this thesis. It is shown that by incorporating discrete event systems, the proposed structure for TS fuzzy models, which we will call non-smooth TS fuzzy models, can accurately represent the smooth (or contin- uous) as well as non-smooth (or discontinuous) dynamics of different classes of electrical and mechanical non-smooth systems including (sliding and non-sliding) Filippov's systems and impacting systems. The different properties of the TS fuzzy modelling (or formalism) are discussed. It is highlighted that the TS fuzzy formalism, taking advantage of its simple structure, does not need a special platform for its implementation. Stability in its new notion of structural stability (stability of a periodic solution) is one of the most important issues in the qualitative analysis of non-smooth systems. An important part of this thesis is focused on addressing stability issues by extending non- smooth Lyapunov theory for verifying the stability of local orbits, which the non-smooth TS fuzzy models can contain. Stability conditions are proposed for Filippov-type and impacting systems and it is shown that by formulating the conditions as Linear Matrix inequalities (LMIs), the onset of non-smooth bifurcations or chaotic phenomena can be detected by solving a feasibility problem. A number of examples are given to validate the proposed approach. Stability robustness of non-smooth TS fuzzy systems in the presence of model uncertainties is discussed in terms of non-smoothness rather than traditional observer design. The LMI stabilization problem is employed as a building block for devising design strategies to suppress the unwanted chaotic behaviour in non-smooth TS fuzzy models. There have been a large number of control applications in which the overall closed-loop sys tem can be stabilized by switching between pre-designed sub-controllers. Inspired by this idea, the design part of this thesis concentrates on fuzzy-chaos control strategies for Filippov-type systems. These strategies approach the design problem by switching be- tween local state-feedback controllers such that the closed-loop TS fuzzy system of interest rapidly converges to the stable periodic solution of the system. All control strategies are also automated as a design problem recast on linear matrix inequality conditions to be solved by modern optimization techniques. Keywords: Takagi-Sugeno fuzzy systems, non-smooth Lyapunov theory, non-smooth dy- namical systems, piecewise-smooth dynamical systems, structural stability, discontinuity- induced bifurcation, chaos controllers, dc-dc converters, Filippov's system, impacting system, linear matrix inequalities.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Speed Control of Separately Excited DC Motor using Neuro Fuzzy Technique

This paper uses NEURO FUZZY TECHNIQUE in estimating speed and controlling it for a separately excited DC motor. The rotor speed of the dc motor can be made to follow an arbitrarily selected trajectory. The purpose is to achieve accurate trajectory control of the speed of saperately excited DC Motor, especially when the motor and load parameters are unknown. Such a neuro fuzzy control scheme consists of two parts. One is the neural identifier which is used to estimate the motor speed error (state error or state error derivative). The second is the fuzzy logic controller which is used to generate a control signal for a chopper & speed control of separately excited DC Motor. The purpose of this technique is to achieve accurate trajectory control of the speed. Such a control scheme consists of two parts. One is the neural identifier which is used to estimate the motor speed. The other is the neural fuzzy logic controller which is used to generate the control signal (fuzzy output)

A family of Lyapunov-based control schemes for maximum power point tracking in buck converters

summary:This paper presents a novel family of Lyapunov-based controllers for the maximum power point tracking problem in the buck converter case. The solar power generation system here considered is composed by a stand-alone photovoltaic panel connected to a DC/DC buck converter. Lyapunov function candidates depending on the output are considered to develop conditions which, in some cases, can be expressed as linear matrix inequalities; these conditions guarantee that the output goes asymptotically to zero, thus implying that the MPPT is achieved. Simulation and real-time results are presented, which validate the effectiveness of the proposals