Alternative energy sources have become a necessity for the socio-economic growth of a country; fossil fuels are declining and by increasing the power demand, the world is on the edge of a global energy crisis. Furthermore, due to the widespread use of traditional energy sources, this creates pollution and global warming effects on the environment. In the light of this, renewable energy such as the wind and solar energy are highly significant and viable solution in order to fulfil power demand, due to its low operating costs and available in bulk quantities which make it exploitation beneficial for the development of any country. Besides that, for over the past decades, the researchers have been working on this enormous challenge. In this review article, we put forward a wide-ranging and significant research conducted on the state of the art control methodologies for wind energy systems. Therefore, author’s main aim is to ensure up-to-date knowledge of wind energy control techniques for the research community and can be considered for future directions. In the available literature, we have summarized numerous wind turbine control techniques with their performance. Furthermore, prospective future advancements and gaps have also been examined comprehensively, and omissions of other researchers are purely unintentional.

https://ijrer.com/index.php/ijrer/article/download/4484/pdf

A Review of the State of the Art Control Techniques for Wind Energy Conversion System

This paper explores the need for renewable based DC microgrid and proposes characteristic features of a standalone DC microgrid. The need for energy management system and its role in DC microgrid has been emphasized. Renewable generating sources such as wind turbine generator and photovoltaic panel require stringent control for harnessing maximum available energy, energy storage system demands efficient management, and DC-link voltage must be maintained constant. These requirements are fulfilled by energy management system, thus it provides intelligence to the system and makes the microgrid reliable. An isolated renewable DC microgrid having proposed features and energy management system has been simulated using MATLAB/SIMULINK. The designed system sustains dynamic conditions and simulation results validate feasibility of DC microgrid and energy management algorithm.

Renewable based DC microgrid with energy management system

This paper designs a new controller to increase efficiency of maximum power point tracking (MPPT) at nominal wind speed based on adaptive PID controller where its coefficients are optimized using a fuzzy controller. PID controllers are widely used in linear systems due to their simple structure and proper response. Due to stochastic changes of wind speed, wind turbines generally have nonlinear nature. In addition, turbines have different dynamic structures regarding their construction conditions. Thus, using a controller which can preserve system stability considering changes of system parameters and obtain reach steady state in the shortest possible time is necessary. In this method, information adopted from wind speed and nonlinear turbine model are used to identify system using closed loop identification. In the following, Hill climbing search (HCS) algorithm is used to determine optimal operating point of the turbine in the nominal wind speed range, online. Advantage of perturb and observe (P&O) methods includes simple structure and adaptability with different stochastic and nonlinear systems. The designed controller minimizes the error between output power of the turbine and the optimized power. This controller is simulated practically on a 3KW wind turbine. Simulation results indicate efficiency and robustness of the designed controller.

/pdf/maximum-power-point-tracking-of-variable-speed-wind-turbines-31qvi8sobb.pdf

Maximum Power Point Tracking of Variable-Speed Wind Turbines Using Self-Tuning Fuzzy PID

Wind turbines require continuous monitoring and control in order to maintain the power output as the wind speed varies. Traditional control techniques using conventional equipment and devices have been used in small scale generators at a commercial or residential level. A range of techniques have been developed and used to control generation output and to satisfy grid code requirements. Such techniques have demonstrated good performance with constant wind speed and linear system parameters. At the same time classical control techniques, based on the linear Proportional Integral controller and low band-width modulation, present several technical issues during lower switching frequency operation as well as slow response to uncertainty in system parameters. It is important to note that wind turbines are non-linear in nature and therefore require robust controllers that can adjust to the changes in the external environment as well as operational conditions and disturbances. For this reason, advanced control schemes have been proposed to mitigate the effects of potential system disturbances. A variety of advanced control methods have recently been applied in response to wind energy conversion problems, such as fuzzy logic, slide mode, adaptive and predictive that have been applied to solve some of these problems. Such techniques are only valid for a specific operational range and do not cover the whole operational region with regard to rate of change of wind speed. Therefore, when considering large scale power generation from wind energy, high turbulence wind velocities and uncertainty in system parameters require the development of new hybrid controllers in order to address such problems. In order to improve

/pdf/hybrid-control-schemes-for-permanent-magnet-synchronous-12kipmcla3.pdf

Hybrid control schemes for permanent magnet synchronous generator wind turbines

Load harmonics compensation of a DFIG based wind energy system is proposed in this paper. The control of voltage and frequency of a variable speed-constant frequency autonomous DFIG based wind energy system is done through an active filter technique. To overcome such type of problem two back to back connected thyristor based Voltage Source Converters (VSC) are used with a DC energy storage system connected at dc link between these two converters. This paper contain a wind energy system with grid-connected doubly fed induction generator (DFIG) are considered. At the stator terminals after regulating the voltage and frequency, the generated error signal between the actual rotor current and the reference rotor a current is pass through hysteresis controller. This generated stator voltage is controlled through rotor current. Amplitude of stator voltage and its frequency are controlled independently. For the diminution of generated harmonics in current and voltage, active filtering and voltage control techniques are used. The presented methodology is applicable for 2MVA DFIG based wind turbine prototype. This proposed model is designed in MATLAB/Simulink and results procured from it are represented and discussed in this paper.

Load Harmonics Compensation in Autonomous DFIG Based Wind Turbine Systems

This paper Proposes Maximum Power Extraction from Wind Turbine with permanent magnet synchronous generator, using MPPT (Maximum Power Point Tracking) control scheme with the help of regulating the dc link Voltage through Boost converter. This MPPT control scheme is applied by using directly the voltage and current of the generator which is much accurate then getting the parameters from the mechanical and other relative transducers will reduce the accuracy and cost. Feasibility of this control become possible from the relation of the power to the rotor speed and the speed is then related to the DC voltage on the rectifier’s side. The components in this wind generation system are Wind Turbine as Prime Mover, PMSG (permanent magnet synchronous generator), rectifier for converting the ac three phase voltage of the PMSG to DC Voltage, Boost converter which will control the DC Voltage of the rectifier and we will have relative speed for the extraction of maximum power from the wind turbine, and a PWM inverter which will invert the DC Voltage supplied by PMSG through rectifier and boost converter to AC Voltage for the load or the grid. The simulation is done with help of MATLAB/SIMULINK and the result is shown which prove that the maximum power point tracking algorithm is suitable for wind turbine.

/pdf/maximum-power-extraction-from-wind-generation-system-using-3cwnpf5f70.pdf

Safiullah Faqirzay

Papers

Maximum Power Extraction from Wind Generation System Using MPPT Control Scheme through Power Electronics Converters