Maximum Power Point Tracking Control for Photovoltaic System Using Adaptive Neuro- Fuzzy "ANFIS"

International audienceDue to scarcity of fossil fuel and increasing demand of power supply, we are forced to utilize the renewable energy resources. Considering easy availability and vast potential, world has turned to solar photovoltaic energy to meet out its ever increasing energy demand. The mathematical modeling and simulation of the photovoltaic system is implemented in the MAT LAB/Simulink environment and the same thing is tested and validated using Artificial Intelligent (Al) Iike AN FIS. This paper presents Maximum Power Point Tracking Control for Photovoltaic System Using Adaptive Neuro- Fuzzy "ANFIS". The PV array has an optimum operating point to generate maximum power at some particular point called maximum power point (MPP). To track this maximum power point and to draw maximum power from PV arrays, MPPT controller is required in a stand-alone PV system. Due to the nonlinearity in the output characteristics of PV array, it is very much essential to track the MPPT of the PV array for varying maximum power point due to the insolation variation. In order to track the MPPT conventional controller like Adaptive Neuro-Fuzzy "ANFIS" and fuzzy logic controller is proposed and simulated. The output of the controller, pulse generated from PWM can switch MOSFET to change the duty cycle of boost DC-DC converter. The result reveals that the maximum power point is tracked satisfactorily for varying insolation condition

Optimizirano povratnokoračno upravljanje momentom indukcijskog motora korištenjem genetičkog algoritma

This paper proposes a novel hybrid control of induction motor, based on the combination of the direct torque control DTC and the backstepping one, optimized by Genetic Algorithm (GA). First the basic evolution of DTC is explained, where the torque and stator flux are controlled by non linear hysteresis controllers which cause large ripple in motor torque at steady state operation. A Backstepping control is applied to overcome these problems, however the used parameters are often chosen arbitrarily, which may affect the controller quality. To find the best parameters, an optimization technique based on genetic algorithm is used. Also, in order to obtain accurate information about stator flux, torque and load torque, open loops estimators are used for this Backstepping control. At last, experimental results are presented in order to prove the efficiency of the above mentioned control technique.U ovom radu predstavljena je nova metoda hibridnog upravljanja indukcijskim motorom, bazirana na kombinaciji direktnog upravljanja momentom (DCT) i povratnokoračnog upravljanja, te optimizirana korištenjem genetičkog algoritma (GA). Prvo je objašnjena osnova razvoja DCT-a, gdje se momentom i tokom statora upravlja nelinearnim histereznim regulatorima što uzrokuje velike propade u momentu motora tijekom ravnotežnog rada. Povratnokoračno upravljanje se primijenjuje kako bi se uklonio ovaj problem, međutim korišteni parametri su najčešće proizvoljno odabrani što može utjecati na kvalitetu upravljanja. Kako bi se našli najbolji parametri koristi se tehnika optimizacije zasnovana na genetičkom algoritmu. Također kako bi se dobili točni podaci o toku statora, momentu i momentu opterećenja potrebni za povratnokoračno upravljanje koriste se estimatori u otvorenoj petlji. Na kraju su prikazani eksperimentalni rezultati kako bi se dokazala efikasnost navedene metode upravljanja

On-line efficiency improvement of induction motor vector controlled

Efficiency improvement is an important challenge for electric motor driven systems. For an induction motor, operation under rated conditions (at rated load with rated flux) is very efficient. However, in many situations, operation with rated flux causes low efficiency especially at light load ranges. In these applications, induction motor should operate at reduced flux which causes a balance between iron losses and copper losses leading to an improved efficiency. This paper concerns energy optimization, i.e. efficiency improvement is carried out via a controller designed on the basis of imposing the rated power factor, by finding a relationship between rotor flux and torque current component which can optimize the compromise between torque and efficiency in steady state as well as in transient state. Experimental results are presented to prove the effectiveness and validity of the proposed controller

Numerical Investigation of Flow in a New DC Pump MHD

Electromagnetic pumps have several advantages to mechanical pumps. They offer maneuverability by directional thrust along with quietness and are conceived with an aim of eliminating all moving parts, being also free from problems of wear and tiredness of use. The flow field in the channel is treated as steady state, incompressible and fully developed laminar flow conditions. Our numerical code DCPMHD uses cylindrical coordinates (r,ϕ , z) and solves the incompressible MHD equations for magnetic vector potential A and fluid velocity V. Using finite volume method for numerical calculation. The numerical results of the performance characteristics of a DC electromagnetic pump are discussed and show that our new concept is capable to deliver bi-directional activation and have a satisfactory controllability, because of its proportional output force and input current relationship

Simulation of Magnetohydrodynamic and Thermal Coupling in the Linear Induction MHD Pump

This article is concerned with the study of a coupling between the stationary Maxwell equations, the transient state Navier Stokes and thermal equations. The model developed computes the magnetic field using the finite element method and calculates the velocity and the temperature using the finite volume method. The paper focuses on the analysis of the flux density, the electromagnetic thrust, the electric power density, the velocity, the pressure and the temperature in the channel of the MHD pump. Effect of the frequency is also presented

Doubly Fed Induction Generator Modeling and Scalar Controlled for Supplying an Isolated Site

This paper deal with the scalar control of the doubly fed induction generator, (DFIG), supplying an isolated site and using the wind power. The DFIG is more adapted for this application, because even if it receives a variable speed on its rotor shaft, due to variable wind speed, a voltage wave with constants magnitude and frequency can be produced. If the injected rotor currents with the specific voltage/frequency ratio according to rotor variable speed and the fixed frequency and magnitude stator voltage are the known problems, than to solve these latter, a simple scalar control method is proposed taking into account the variable speed condition. Experimental results are given in this work so as to attest the feasibility and the simplicity of our method

Backstepping Glycemic Control of Type 1 Diabetes for Implementation on an Embedded System

In this paper a nonlinear control intended for Blood glucose regulation for Type 1 Diabetes patients is considered. The control law is designed using the Lyapunov theory associated with a Kalman filter to estimate the system states. The asymptotic stability of the overall system is theoretically proven. The proposed control scheme will be implemented in a low cost embedded system. The simulation results confirm the effectiveness of the proposed control

Robust Current Control of a Small-Scale Wind–Photovoltaic Hybrid System Based on the Multiport DC Converter

In this paper, a robust current control of the hybrid renewable energy system (HRES), based on the PV-Wind system, is proposed. The HRES is connected to a multiport converter to synchronize the multi-source system with one DC-Bus. Due to their ability to integrate many renewable energy sources (RES) individually or simultaneously, multiport converters (MPC) are an innovative method suitable for renewable energy applications. Recently, many DC-DC converter designs and topologies have emerged to ensure the highest possible efficiency of hybrid RESs. The multiport converter is a typical coupling system with several modes of operation. Thus, the design of its controller become complicated. To stabilize the DC-Bus voltage, a battery has been added to the system. In this HRES configuration, all sources are connected in parallel via the multiport DC converter. We used the multiport DC converter to minimize the intermittent character of solar and wind and control the energy flow between the different power sources and the load, as well as to increase the performance of the system. The nonlinear robust control structure is based on Lyapunov approach to overcome the nonlinear model of the system to improve robustness and guarantees the asymptotic stability. The proposed control law is implemented and tested on dSPACE-DS1104. The results show the effectiveness and the feasibility of the proposed controller