Model simplification and optimization of a passive wind turbine generator

In this paper, the design of a "low cost full passive structure" of wind turbine system without active electronic part (power and control) is investigated. The efficiency of such device can be obtained only if the design parameters are mutually adapted through an optimization design approach. For this purpose, sizing and simulating models are developed to characterize the behavior and the efficiency of the wind turbine system. A model simplification approach is presented, allowing the reduction of computational times and the investigation of multiple Pareto-optimal solutions with a multiobjective genetic algorithm. Results show that the optimized wind turbine configurations are capable of matching very closely the behavior of active wind turbine systems which operate at optimal wind powers by using a MPPT control device

DFIG versus PMSG for marine current turbine applications

Emerging technologies for marine current turbine are mainly relevant to works that have been carried out on wind turbines and ship propellers. It is then obvious that many electric generator topologies could be used for marine current turbines. As in the wind turbine context, doubly-fed induction generators and permanent magnet generators seems to be attractive solutions to be used to harness the tidal current energy. In this paper, a comparative study between these two generators type is presented and fully analyzed in terms of generated power, maintenance and operation constraints. This comparison is done for the Raz de Sein site (Brittany, France) using a multi physics modeling simulation tool. This tool integrates, in a modular environment, the resource model, the turbine hydrodynamic model and the generators models

Power Extraction Strategy of a Robust kW Range Marine Tidal Turbine Based on Permanent Magnet Synchronous Generators and Passive Rectifiers

This paper presents a kW range marine tidal current power generation system consisting of a fixed pitch marine current turbine (MCT) with two permanent magnet synchronous generators in the turbine shaft, two diode rectifiers (each rectifier is associated with a permanent magnet synchronous generator) and a DC source voltage. This system is designed for a kW range robust power supply. The specificity of the proposed system is that the two generators have different numbers of turns in their windings and the two rectifiers are in parallel in the same DC source. It has been demonstrated that the proposed system is able to harness very efficiently the energy of the turbine in the whole tidal cycle. The proposed system is interesting because it does not need complex control system and it allows minimizing converter losses costs due to electronic devices as controlled IGBT PWM converters usually used in conventional power generation systems. The analytical results have been confirmed numerically using PSIM software for two kW range generators with the same magnetic circuit and different winding number of turns

Back-to-back Converter Control of Grid-connected Wind Turbine to Mitigate Voltage Drop Caused by Faults

Power electronic converters enable wind turbines, operating at variable speed, to generate electricity more efficiently. Among variable speed operating turbine generators, permanent magnetic synchronous generator (PMSG) has got more attentions due to low cost and maintenance requirements. In addition, the converter in a wind turbine with PMSG decouples the turbine from the power grid, which favors them for grid codes. In this paper, the performance of back-to-back (B2B) converter control of a wind turbine system with PMSG is investigated on a faulty grid. The switching strategy of the grid side converter is designed to improve voltage drop caused by the fault in the grid while the maximum available active power of wind turbine system is injected to the grid and the DC link voltage in the converter is regulated. The methodology of the converter control is elaborated in details and its performance on a sample faulty grid is assessed through simulation

Generator Systems for Marine Current Turbine Applications: A Comparative Study

Emerging technologies for marine current turbines are mainly related to works that have been carried out on wind turbines and ship propellers. It is then obvious that many electric generator topologies could be used for marine current turbines. As in the wind turbine context, doubly-fed induction generators and permanent magnet generators seem to be attractive solutions for harnessing the tidal current energy. In this paper, a comparative study between these two generator types is presented and fully analyzed in terms of generated power, maintenance, and operation constraints. This comparison is done for the Raz de Sein site (Brittany, France) using a multiphysics modeling simulation tool. This tool integrates, in a modular environment, the resource model, the turbine hydrodynamicmodel, and generator models. Experiments have also been carried out to confirm the simulation results.Financement de thèse de Brest Métropole Océan

Multi-disciplinary robust design of variable speed wind turbines

This paper addresses the preliminary robust multi-disciplinary design of small wind turbines. The turbine to be designed is assumed to be connected to the grid by means of power electronic converters. The main input parameter is the yearly wind distribution at the selected site, and it is represented by means of a Weibull distribution. The objective function is the electrical energy delivered yearly to the grid. Aerodynamic and electrical characteristics are fully coupled and modelled by means of low- and medium-fidelity models. Uncertainty affecting the blade geometry is considered, and a multi-objective hybrid evolutionary algorithm code is used to maximise the mean value of the yearly energy production and minimise its variance

Electric Generators Fitted to Wind Turbine Systems: An Up-to-Date Comparative Study

International audienceThis paper describes a comparative study allowing the selection of the most appropriate innovative structures for electrical machines for a wind turbine system. This study is based on an exhaustive review of the state of the art and on an effective comparison of the performances of the three main conventional electric generator in wind energy application system that are the Doubly-Fed Induction Generator (DFIG), the Squirrel-Cage Induction Generator (SCIG), the Permanent Magnet Synchronous Generator (PMSG), and an innovative machine that is the Switched Reluctance Generator (SRG). The main conclusion drawn by the proposed comparative study is that the innovative switched reluctance generator is able fulfills the major requirements of a wind energy system

Integrated Optimal Design of a Passive Wind Turbine System: An Experimental Validation

This work presents design and experimentation of a full passive wind turbine system without active electronic part(power and control). The efficiency of such device can be obtained only if the system design parameters are mutually adapted through an Integrated Optimal Design (IOD) method. This approach based on multiobjective optimization, aims at concurrently optimizing the wind power extraction and the global system losses for a given wind speed profile while reducing the weight of the wind turbine generator. It allows us to obtain the main characteristics (geometric and energetic features) of the optimal Permanent Magnet Synchronous Generator (PMSG) for the passive wind turbine. Finally, experiments on the PMSG prototype built from this work show a good agreement with theoretical predictions. This validates the design approach and confirms the effectiveness of such passive device

Modern Control Approaches for a Wind Energy Conversion System based on a Permanent Magnet Synchronous Generator (PMSG) Fed by a Matrix Converter

This “paper proposes a super-twisting adaptive Control Approaches for a Wind Energy Conversion System Based on a Permanent Magnet Synchronous Generator (PMSG) Fed by a matrix sliding mode for tracking the maximum power point of wind energy conversion systems using permanent magnet synchronous generators (PMSGs). As the adaptive control algorithm employed retains the robustness properties of classical wind energy conversion system control methods when perturbations and parameter uncertainties are present, it can be considered an effective solution; at the same time, it reduces chattering by adjusting gain and generating second-order adaptive control methods. The Egyptian power system (EPS), a three-zone interconnected microgrid (MG), and a single machine linked to the grid are only a few examples of the power systems for which this article introduces the concept of direct adaptive control (SMIB).The goal of our work is to maximize the captured power by solving a multi-input multi-output tracking control problem. In the presence of variations in stator resistance, stator inductance, and magnetic flux linkage, simulation results are presented using real wind speed data and discussed for the proposed controller and four other sliding mode control solutions for the same problem. The proposed controller achieves the best trade-off between tracking performance and chattering reduction among the five considered solutions: compared to a standard sliding mode control algorithm, it reduces chattering by two to five orders of magnitude, and steadystate errors on PMSG rotor velocity by one order of magnitude”. The purpose of this article is to examine wind turbine control system techniques and controller trends related to permanent magnet synchronous generators. The article presents an overview of the most popular control strategies for PMSG wind power conversion systems. There are several kinds of nonlinear sliding modes, such as direct power, backstepping, and predictive currents. To determine the performance of each control under variable wind conditions, a description of each control is presented, followed by a simulation performed in MATLAB /Simulink. This simulation evaluates the performance of each control in terms of reference tracking, response times, stability, and signal quality. Finally, this work was concluded with a comparison of the four controls to gain a better understanding of their effects. “Moreover, it reduces the above-mentioned steady-state error by four orders of magnitude compared to a previously-proposed linear quadratic regulator based integral sliding mode control law.  A dynamic model is simulated under both variable step and random wind speeds using the DEV-C++ software, and the results are plotted using MATLAB. The obtained results demonstrate the robustness of the proposed controller in spite of the presence of different uncertainties when compared to the classical direct torque control technique

Full- & Reduced-Order State-Space Modeling of Wind Turbine Systems with Permanent-Magnet Synchronous Generator

Wind energy is an integral part of nowadays energy supply and one of the fastest growing sources of electricity in the world today. Accurate models for wind energy conversion systems (WECSs) are of key interest for the analysis and control design of present and future energy systems. Existing control-oriented WECSs models are subject to unstructured simplifications, which have not been discussed in literature so far. Thus, this technical note presents are thorough derivation of a physical state-space model for permanent magnet synchronous generator WECSs. The physical model considers all dynamic effects that significantly influence the system's power output, including the switching of the power electronics. Alternatively, the model is formulated in the $(a,b,c)$- and $(d,q)$-reference frame. Secondly, a complete control and operation management system for the wind regimes II and III and the transition between the regimes is presented. The control takes practical effects such as input saturation and integral windup into account. Thirdly, by a structured model reduction procedure, two state-space models of WECS with reduced complexity are derived: a non-switching model and a non-switching reduced-order model. The validity of the models is illustrated and compared through a numerical simulation study.Comment: 23 pages, 11 figure