Generator Based Wind Turbine System Research Articles

Enhanced Control of Doubly Fed Induction Generator Based Wind Turbine System Using Fractional-Order Fuzzy PD+I Regulator

Enhanced Control of Doubly Fed Induction Generator Based Wind Turbine System Using Fractional-Order Fuzzy PD+I Regulator

Limits of reactive power compensation of a doubly fed induction generator based wind turbine system

The doubly fed induction generator (DFIG) systems feature a significant amount of free power capacity that may be used for reactive power adjustment when they are put into practical use. This change, which is occasionally overlooked, is a significant one. Using DFIG systems for wind turbines (WT), this paper explored strategies for reducing and using reactive power. In order to investigate the power characteristic and how it is regulated in DFIG systems, a mathematical model for the steady-state performance of DFIG WT has been developed and presented. Here is a detailed derivation of the limiting range of DFIG's reactive power capacity as well as the physical constraints on reactive power output. The distribution of the DFIG WT at a distribution network's end is demonstrated by a simulation example. Within this simulation, reactive power management strategy, load fluctuation, and the change in wind speed are all taken into consideration. Due to the possibility of a rise in the voltage at the access point, can concluded that both acceptable and efficient to use DFIG WT's reactive power capabilities as an additional continuous reactive power source for effectiveness.

Nonlinear Stochastic Adaptive Control for DFIG-Based Wind Generation System

The aim of this paper is to extract the maximum power from wind energy for the doubly fed induction generator based wind turbine system (DFIG-WT) under the continuous stochastic perturbations of wind speed. The DFIG-WT is modeled as the Itô stochastic differential equations. The stochastic backstepping control method and the gain suppressing inequality technique are employed to guarantee that the relative rotor speed to the optimal value is bounded in probability. Furthermore, we extend the bounded result to the asymptotic stability of the rotor speed control loop. In addition, the parametric uncertainties in DFIG-WT are also considered in our control synthesis. The simplicity, robustness and efficiency of the designed controller are verified under the special wind speed with white noise by the numerical simulation of a 660 KW DFIG-WT.

Enhanced control of doubly fed induction generator based wind turbine system using soft computing assisted fractional order controller

This paper proposes teaching learning based optimization (TLBO) algorithm assisted fractional order controller for control of Rotor side converter (RSC) and Grid side converter (GSC) for efficient and optimal control of doubly fed induction machine based wind turbine (WT) system. The proposed fractional order proportional integral (FOPI) controller is tuned using Genetic algorithm (GA), particle swarm optimization (PSO) and TLBO techniques. The rotating reference frame with stator flux alignment dependent field oriented vector control scheme is accomplished for decoupled optimal power control. Proposed DFIG based WT system implemented and simulated using MATLAB/Simulink. Simulation results of proposed TLBO based fractional order control are compared with GA and PSO tuned FOPI controller. The simulation results obtained are expedient that TLBO tuned FOPI is more prominent in DC link voltage control and shown promising results as compared to GA and PSO tuned FOPI Controller in terms of the of the solution time required and time domain performance parameters.

Enhanced control and operation for brushless doubly-fed induction generator based wind turbine system under grid voltage unbalance

This paper presents an enhanced control and operation for brushless doubly-fed induction generator (BDFIG) based wind turbine system under grid voltage unbalance by considering the controls of machine side converter(MSC) and grid side converter(GSC) together. The MSC is controlled to eliminate torque oscillations and realize decoupling control of power winding(PW) average active and reactive power while the GSC is controlled to eliminate oscillations in the total output active power. A single current closed-loop controller composed of a positive sequence current controller in the positive synchronous reference frame and a negative sequence current controller in the negative synchronous reference frame is designed for both MSC and GSC. To achieve decoupling control and improve system dynamic response, in current loops, all the disturbances and cross-coupling terms are derived and used for feedforward control. A fast sequence decomposition algorithm is employed to reduce the considerable time delays of using notch filers. In order to validate the effectiveness of proposed control, simulations for a 2WM BDFIG based wind generation system were carried out, the results demonstrated that the proposed control can effectively eliminate oscillations of BDFIG torque and total output active power, and has good dynamic and stable performance.

Fuzzy Logic Based Fault Current Prediction in Double Fed Induction Generator Based Wind Turbine System

Over the past few years, the wind turbine industry has expanded widely and is increasingly taking production into account. There are various reasons why wind energy in electricity networks can be accumulated. In the event of a wind production, it not only remains safe and sustainable, but has low operating costs. DFIG's numerous advantages in the production of power electronic converters and the growth of double feeding induction generators, and their benefits of low conversion capacities, high energy and flexible power control were extensively used in large-scale wind power applications. DFIG as a wind turbine linked to a grid which is subjected to various forms of faults in this innovation. Crowbar is used and is a kind of a safety mechanism for wind turbine generators. Fuzzy Logic is also used to safeguard DFIG for defects presented in this paper.

New grid synchronization and power control scheme of doubly-fed induction generator based wind turbine system using fuzzy logic control.

This paper deals with the analysis, modeling and control of a doubly-fed induction generator in variable speed wind turbine systems. The start-up procedure of the wind turbine including the grid synchronization has been established. New sensorless control schemes were developed, the first one is designed for standalone mode and grid synchronization named direct voltage control, the second one is designed for grid-connected mode named direct power control. To improve the robustness of the controlled system performance in case of machine parameters variations, a fuzzy logic controller was introduced. Various operation modes have been tested including accelerating and braking of the wind turbine, limited power and speed operation mode, power maximization mode, standalone operation mode with supplying a variable load. Simulation of the full start-up procedure was performed using Matlab/SimPowerSystems. The simulation results for several transient conditions demonstrated the effectiveness of the proposed control strategy.

Direct Power Control Optimization for Doubly Fed Induction Generator Based Wind Turbine Systems

This study presents an intelligent metaheuristics-based design procedure for the Proportional-Integral (PI) controllers tuning in the direct power control scheme for 1.5 MW Doubly Fed Induction Generator (DFIG) based Wind Turbine (WT) systems. The PI controllers’ gains tuning is formulated as a constrained optimization problem under nonlinear and non-smooth operational constraints. Such a formulated tuning problem is efficiently solved by means of the proposed Thermal Exchange Optimization (TEO) algorithm. To evaluate the effectiveness of the introduced TEO metaheuristic, an empirical comparison study with the homologous particle swarm optimization, genetic algorithm, harmony search algorithm, water cycle algorithm, and grasshopper optimization algorithm is achieved. The proposed TEO algorithm is ensured to perform several desired operational characteristics of DFIG for the active/reactive power and DC-link voltage simultaneously. This is performed by solving a multi-objective function optimization problem through a weighted-sum approach. The proposed control strategy is investigated in MATLAB/environment and the results proved the capabilities of the proposed control system in tracking and control under different scenarios. Moreover, a statistical analysis using non-parametric Friedman and Bonferroni–Dunn’s tests demonstrates that the TEO algorithm gives very competitive results in solving global optimization problems in comparison to the other reported metaheuristic algorithms.

A novel control solution for improved trajectory tracking and LVRT performance in DFIG-based wind turbines

This paper presents a new control strategy for the rotor side converter of Doubly-Fed Induction Generator based Wind Turbine systems, under severe voltage dips. The main goal is to fulfill the Low Voltage Ride Through performance, required by modern grid codes. In this respect, the key point is to limit oscillations (particularly on rotor currents) triggered by line faults, so that the system keeps operating with graceful behavior. To this aim, a suitable feedforward-feedback control solution is proposed for the DFIG rotor side. The feedforward part exploits oscillation-free reference trajectories, analytically derived for the system internal dynamics. State feedback, designed accounting for control voltage limits, endows the system with robustness and further tame oscillations during faults. Moreover, improved torque and stator reactive power tracking during faults is achieved, proposing an exact mapping between such quantities and rotor-side currents, which are conventionally used as controlled outputs. Numerical simulations are provided to validate the capability of the proposed approach to effectively cope with harsh faults.

Modern control strategies of doubly-fed induction generator based wind turbine system

A doubly-fed induction generator(DFIG) based configuration is still preferred by wind turbine manufacturers due to the cost-effective power converter and independent control of the active power and reactive power. To cope with stricter grid codes(e.g. reactive power compensation, low voltage ride-through operation, as well as steady and safe operation during long-term distorted grid), control strategies are continuously evolving. This paper starts with a control strategy using the combined reactive power compensation from both the back-to-back power converters for their optimized lifetime distribution under normal grid conditions. Afterwards, an advanced demagnetizing control is proposed to keep the minimum thermal stress of the rotor-side converter in the case of the short-term grid fault. A modularized control strategy of the DFIG system under unbalanced and distorted grid voltage is discussed, with the control targets of the smooth active and reactive power or the balanced and sinusoidal current of the rotor-side converter and the grid-side converter. Finally, a bandwidth based repetitive controller is evaluated to improve the DFIG system's robustness against grid frequency deviation.