A. I. Alolah

Fuzzy controller for three phases induction motor drives

Because of the low maintenance and robustness induction motors have many applications in the industries. Most of these applications need fast and smart speed control system. This paper introduces a smart speed control system for induction motor using fuzzy logic controller. Induction motor is modeled in synchronous reference frame in terms of dq form. The speed control of induction motor is the main issue achieves maximum torque and efficiency. Two speed control techniques, Scalar Control and Indirect Field Oriented Control are used to compare the performance of the control system with fuzzy logic controller. Indirect field oriented control technique with fuzzy logic controller provides better speed control of induction motor especially with high dynamic disturbances. The model is carried out using Matlab/Simulink computer package. The simulation results show the superiority of the fuzzy logic controller in controlling three-phase induction motor with indirect field oriented control technique.

PSO-Based Smart Grid Application for Sizing and Optimization of Hybrid Renewable Energy Systems

This paper introduces an optimal sizing algorithm for a hybrid renewable energy system using smart grid load management application based on the available generation. This algorithm aims to maximize the system energy production and meet the load demand with minimum cost and highest reliability. This system is formed by photovoltaic array, wind turbines, storage batteries, and diesel generator as a backup source of energy. Demand profile shaping as one of the smart grid applications is introduced in this paper using load shifting-based load priority. Particle swarm optimization is used in this algorithm to determine the optimum size of the system components. The results obtained from this algorithm are compared with those from the iterative optimization technique to assess the adequacy of the proposed algorithm. The study in this paper is performed in some of the remote areas in Saudi Arabia and can be expanded to any similar regions around the world. Numerous valuable results are extracted from this study that could help researchers and decision makers.

Sizing and techno-economic analysis of stand-alone hybrid photovoltaic/wind/diesel/battery power generation systems

This paper introduces a new proposed design and optimization simulation program for the techno-economic sizing of a stand-alone hybrid photovoltaic/wind/diesel/battery energy system using the iterative optimization. The main function of the new proposed simulation program is to determine the optimum size of each component of a hybrid renewable energy system for the lowest price of generated energy and the lowest value of dummy energy at highest reliability. An accurate methodology for pairing between five Saudi Arabia sites and ten wind turbines from different manufacturers to maximize energy production and minimize the price of the generated power is introduced. This methodology changes the penetration ratio of the renewable energy sources in certain increments to meet the load requirements of the sites under study. A detailed economic methodology to obtain the price of the generated energy is introduced. The new proposed simulation program is implemented in flexible fashion, which is not possible for th...

Modified DFIG control strategy for wind energy applications

A detailed computer simulation for interconnecting wind energy system to an electric utility is presented. The proposed system consists of four high rating wind turbines each one uses double fed induction generator (DFIG). Two back to back bidirectional PWM inverters are used in the rotor circuit of each DFIG to be interfaced with the electrical utility. The simulation incorporates a flexible independent control for the active and reactive powers by using field oriented control technique. Also it introduces an effective technique to track the maximum power point of the wind energy by controlling the pitch angle and rotational speed. Active power is controlled through the direct axis current of the rotor side converter in outer control layer. Reactive power is controlled by the quadrature axis current of the rotor side converter. The system shows a stable operation under different operating conditions.

Digital implementation of general purpose fuzzy logic controller for photovoltaic maximum power point tracker

This paper introduces an implementation of a general purpose fuzzy logic controller for use with general purpose embedded processors. This controller is used in the applications of maximum power point tracker of photovoltaic energy system as an application. However, the proposed model is very flexible to be applied in various and different applications. The design is made to be scalable in terms of number of inputs and number of membership functions (MFs) in both inputs side and output side. The proposed model was written in C language due its popularity and efficiency in embedded and control applications. An example of maximum power point tracker of photovoltaic energy system with 2-inputs/7-MFs each and 1-output/7-MFs is used for demonstration and verification purpose. The general purpose fuzzy logic controller shows consistency with the result obtained from simulation.

Energy management and renewable energy integration in smart grid system

Smart grid is a concept by which the existing electrical grid infrastructure is being upgraded with integration of multiple technologies such as, two-way power flow, two-way communication, automated sensors, advanced automated controls and forecasting system. Smart grid enables interaction between the consumer and utility which allow the optimal usage of energy based on environmental, price preferences and system technical issues. This enables the grid to be more reliable, efficient and secure, while reducing greenhouse gases. This paper presents a survey of the recent literature on integrating renewable energy sources into smart grid system. Various management objectives, such as improving energy efficiency, maximizing utilization, reducing cost, and controlling emission have been explored.

Simulation and Practical Implementation of ANFIS-Based MPPT Method for PV Applications Using Isolated Ćuk Converter

Photovoltaic (PV) module behavior is not linear in nature with respect to environmental conditions and hence exhibits nonlinear PV curves. There is only a single point in the nonlinear PV curve at which the power is maximum. Therefore, special methods have been proposed to track this maximum power point (MPP). This paper proposed an intelligent method for MPP tracking (MPPT) based on adaptive neuro-fuzzy inference system (ANFIS) controller. The proposed system consists of a PV module connected to a DC-DC isolated Cuk converter and load. A MATLAB/SIMULINK-based MPPT model is built to test the behavior of the proposed method. The proposed method is tested under different weather scenarios. Simulation results exhibit the successful tracking of the proposed method under all ambient conditions. Comparison of the tracking behavior of the proposed method with the perturb and observe method is also presented in the simulation results. In addition, a 220 W prototype with the help of dSPACE 1104 data acquisition system is built and tested under practical weather conditions on a sunny day as well as on a cloudy day. Experimental results are presented to verify the effectiveness of the proposed method. These results exhibit satisfactory performance under different practical weather conditions.

Load management as a smart grid concept for sizing and designing of hybrid renewable energy systems

ABSTRACT Optimal sizing of hybrid renewable energy systems (HRES) to satisfy load requirements with the highest reliability and lowest cost is a crucial step in building HRESs to supply electricity to remote areas. Applying smart grid concepts such as load management can reduce the size of HRES components and reduce the cost of generated energy considerably. In this article, sizing of HRES is carried out by dividing the load into high- and low-priority parts. The proposed system is formed by a photovoltaic array, wind turbines, batteries, fuel cells and a diesel generator as a back-up energy source. A smart particle swarm optimization (PSO) algorithm using MATLAB is introduced to determine the optimal size of the HRES. The simulation was carried out with and without division of the load to compare these concepts. HOMER software was also used to simulate the proposed system without dividing the loads to verify the results obtained from the proposed PSO algorithm. The results show that the percentage of division of the load is inversely proportional to the cost of the generated energy.

Dynamic performance enhancement of a grid-connected wind farm using doubly fed induction machine-based flywheel energy storage system

This paper presents the dynamic performance enhancement of a wind farm connected to an IEEE-39 bus New England test system using doubly-fed induction machine (DFIM)-based flywheel energy storage system (FESS). The variable wind speed causes fluctuations in the output power of the wind farms. The use of FESS smoothes the power of the wind farm and improves the dynamic response of the system during fluctuating wind speeds. A DFIM-based FESS is proposed in this study which works on an effective control technique. The cascaded black-box optimization technique based proportional-integral (PI) control strategy is implemented on the FESS. The PI controllers are used to control the insulated gate bipolar transistor (IGBT) based rotor side converter (RSC) and the grid side converter (GSC) of the DFIM. The PI controller In-depth modeling and control strategy of the system under study is presented. The effectiveness of the proposed system is tested under real-time wind speed data. The validity of the system is verified by the simulation results which are carried out using PSCAD/EMTDC.

A smart technique for optimization and simulation of hybrid photovoltaic/wind/diesel/battery energy systems

This paper introduces a new proposed design and optimization simulation program for techno-economic sizing of stand-alone hybrid PV/wind/diesel/battery energy system. The main function of the new proposed simulation program (NPSP) is to determine the optimum size of each component of the hybrid energy system (HES) for lowest cost of kWh generated at highest reliability. An accurate methodology for pairing between five Saudi Arabia sites and ten wind turbines (WTs) from different manufacturers has been introduced. An economic methodology to obtain the price of the generated kWh has been introduced. The proposed program performed the optimal sizing steps in short time and high accuracy. Many valuable results can be extracted from the proposed program that could help researchers and decision makers.