Hussein Ibrahim

Energy Management and Control System for Laboratory Scale Microgrid Based Wind-PV-Battery

This paper proposes an energy management and control system for laboratory scale microgrid based on hybrid energy resources such as wind, solar, and battery. Power converters and control algorithms have been used along with dedicated energy resources for the efficient operation of the microgrid. The control algorithms are developed to provide power compatibility and energy management between different resources in the microgrid. It provides stable operation of the control in all microgrid subsystems under various power generation and load conditions. The proposed microgrid, based on hybrid energy resources, operates in autonomous mode and has an open architecture platform for testing multiple different control configurations. A real-time control system has been used to operate and validate the hybrid resources in the microgrid experimentally. The proposed laboratory scale microgrid can be used as a benchmark for future research in smart grid applications.

Study of a Hybrid Wind-Diesel System with Compressed Air Energy Storage

The electricity supply in remote areas around the world uses mostly diesel generators. This method, relatively inefficient and expensive, is responsible for the emission of 1.2 million tons of greenhouse gas (GHG) annually, only in Canada. Some low and high penetration wind-diesel hybrid systems (WDS) have been experimented in order to reduce the diesel consumption. The use of a high penetration system together with compressed air energy storage (CAES) it is a viable alternative to improve the overall percentage of renewable energy and reduce the cost of electricity. In this paper we compare different technical solutions for the CAES system and choose the one that optimize the performance and the cost of the overall system. While in this extended abstract only a superficial description of this system is introduced, detailed results of the simulation will be presented in the complete paper. This new design conducts to the increase of diesel power and efficiency, to the reduction of fuel consumption and GHG emissions, in addition to economies on the maintenance and replacement cost of the diesels.

Techno-Economic Analysis of Different Energy Storage Technologies

Overall structure of electrical power system is in the process of changing. For incremental growth, it is moving away from fossil fuels major source of energy in the world today to renewable energy resources that are more environmentally friendly and sustainable [1]. Factors forcing these considerations are (a) the increasing demand for electric power by both developed and developing countries, (b) many developing countries lacking the resources to build power plants and distribution networks, (c) some industrialized countries facing insufficient power generation and (d) greenhouse gas emission and climate change concerns. Renewable energy sources such as wind turbines, photovoltaic solar systems, solar-thermo power, biomass power plants, fuel cells, gas micro-turbines, hydropower turbines, combined heat and power (CHP) micro-turbines and hybrid power systems will be part of future power generation systems [2-8].

Technical and financial benefits of electrical energy storage

Traditionally, electricity networks are dimensioned on peak demand. This is inevitable due to the fact that storage of substantial amounts of electricity is technically and economically infeasible. As a result, a vast amount of currently unused network capacity is available. When this could be used, much more energy could be transported with the same network so that investments on network reinforcements could be postponed or omitted. To this end, it must be possible to shift demand for electricity in time or, more precisely, to shift the transport of electricity in time. In principle, this can be done by incorporating (distributed) electricity storage in the networks. This paper attempts to summarize the current state of knowledge regarding energy storage technologies for electric power grid. It is intended to serve as a reference for policymakers interested in understanding the range of technologies and applications associated with energy storage, comparing them, when possible, in a structured way to highlight key characteristics relevant to widespread use.

Implementation of Sliding Mode Control System for Generator and Grid Sides Control of Wind Energy Conversion System

This paper presents a second order sliding mode control strategy to control the generator and the grid sides of a variable speed experimental wind energy conversion system. At the generator side, the rotational speed is controlled to track a profile generated from the power curve of the wind turbine for maximum power extraction. At the grid side, the dc-link voltage is regulated for a proper transfer of power. The control strategy is based on a disturbed single input-single output error model and a second order sliding mode control algorithm. The proposed second order sliding mode control strategy offers interesting characteristics such as robustness to parametric uncertainties in the turbine and the generator as well as external disturbances. The proposed strategy, for speed and dc-link voltage control in wind energy conversion system, is validated on an emulated wind turbine driven by the OPAL-RT real-time simulator (OP5600). Experimental results show that the proposed control strategy is effective in terms of speed and dc-link voltage control. The sliding mode control approach is robust against unknown disturbances, parametric variations, and uncertainties in the system. Furthermore, it produces no chattering in the generated torque, which reduces the mechanical stress on the wind turbine.

Modeling solar photovoltaic cell and simulated performance analysis of a 250W PV module

The main purpose of this study is to develop the mathematical model of solar photovoltaic (PV) cell and to simulate its behavior. The study includes the performance analysis of a 250W PV module and its behavior on different temperature conditions, irradiance levels. It also focuses on the effects of varying shunt and series resistances. The model has been developed considering possible environmental effects on solar PV generation. The results of the characteristics curves in this paper are compared to the curves provided by the CS6P-250M PV module datasheet. Using this model it is possible to simulate the behavior of any large scale PV array or solar Photovoltaic Energy Conversion Systems (PVECS). The model was developed by using Matlab®/Simulink” software. This model can be used for further simulation based research and analysis on PVECS.

Nonlinear model predictive controller with state observer for speed sensorless induction generator–wind turbine systems

In this article, the problem of tracking control for variable speed induction generator–wind energy conversion system is investigated using nonlinear predictive control. A rotor speed predictive control algorithm has been designed to control the angular speed of the machine in order to allow the wind energy conversion system to operate with maximum power extraction. The generator torque and uncertainties are estimated and injected into the control law to improve the tracking performance. Control action is carried out assuming that all the states are known by measurement. Then, a state observer is implemented and Lyapunov method is used to prove the global stability of the complete continuous control scheme. Simulation is carried out to verify the performance of the proposed control system.

Control system for hybrid wind diesel based microgrid

Control system developed for hybrid wind diesel system (HWDS) based microgrid is presented. The hybrid system consists of six double fed induction generator (DFIG) based wind turbine generation system, a diesel generation system with synchronous machine and electrical power grid supply. Control system developed for both rotor side and grid side power converter is simulated. A maximum power point tracking (MPPT) control system is developed and simulated for rotor side power converter to track the optimum speed for achieving maximum power extraction from available wind. Vector control based voltage regulation system is developed and simulated for grid side power converter. A dynamic model of HWDS is developed to study the system operating behavior under isolated wind diesel mode and grid connected mode. The complete HWDS is modeled and simulated in MATLAB Simulink environment. Simulation results to validate the performance of developed control system are presented.

Maximum power point tracking and frequency control for hybrid wind diesel system supplying an isolated load

A control strategy developed for hybrid wind-diesel system (HWDS) is presented in this paper. The proposed system consists of the induction generator based wind turbine generation (WTG) system, IGBT based power electronics converters, diesel generator (DG) unit and dump load (DL) system. Developed control strategy shares the required power generation between the WTG and DG unit. The control system operates the wind turbine to achieve maximum power extraction using maximum power point tracking (MPPT) scheme, and simultaneously controls the dump load to absorb excessive power generation, in turn regulates the frequency of power supply. The DG unit is controlled for supplementing the generated power from WTG to supply the complete load power demand. The complete system is modeled and simulated using SimPowerSystems toolbox from Matlab-Simulink software package.

Control of small-scale wind/diesel/battery hybrid standalone power generation system based on fixed speed generators for remote areas

In this paper control design for safe and effective operation of small-scale hybrid wind/diesel/Battery standalone power generation system (WT-DG HSPGS) employing fixed speed generators is investigated. To compensate the fluctuation of wind power, reduce the run-time of the diesel generator (DG), regulate the AC voltage and the system frequency, as well as, to improve the power quality at the PCC, STATCOM supported by battery energy storage system (BESS) is controlled employing synchronous reference frame (SRF) theory and estimated in-phase and quadrature unit AC voltage templates. To synchronize the DG to the PCC, breaker switch is controlled using the estimated voltage phase angle and the system frequency. To protect BESS from overcharging, dump loads is controlled using simple approach based on BESS limit charging voltage. To test the performance of the proposed WT-DG HSPGS and their developed control algorithms under presence of balanced/unbalanced, linear/nonlinear loads and change in climate conditions, simulations are carried out using MATLAB/Simulink.