scholarly journals Dynamic Modeling and Robust Controllers Design for Doubly Fed Induction Generator-Based Wind Turbines under Unbalanced Grid Fault Conditions

Energies ◽  
2019 ◽  
Vol 12 (3) ◽  
pp. 454 ◽  
Author(s):  
Imran Khan ◽  
Kamran Zeb ◽  
Waqar Din ◽  
Saif Islam ◽  
Muhammad Ishfaq ◽  
...  

High penetration of large capacity wind turbines into power grid has led to serious concern about its influence on the dynamic behaviors of the power system. Unbalanced grid voltage causing DC-voltage fluctuations and DC-link capacitor large harmonic current which results in degrading reliability and lifespan of capacitor used in voltage source converter. Furthermore, due to magnetic saturation in the generator and non-linear loads distorted active and reactive power delivered to the grid, violating grid code. This paper provides a detailed investigation of dynamic behavior and transient characteristics of Doubly Fed Induction Generator (DFIG) during grid faults and voltage sags. It also presents novel grid side controllers, Adaptive Proportional Integral Controller (API) and Proportional Resonant with Resonant Harmonic Compensator (PR+RHC) which eliminate the negative impact of unbalanced grid voltage on the DC-capacitor as well as achieving harmonic filtering by compensating harmonics which improve power quality. Proposed algorithm focuses on mitigation of harmonic currents and voltage fluctuation in DC-capacitor making capacitor more reliable under transient grid conditions as well as distorted active and reactive power delivered to the electric grid. MATLAB/Simulink simulation of 2 MW DFIG model with 1150 V DC-linked voltage has been considered for validating the effectiveness of proposed control algorithms. The proposed controllers performance authenticates robust, ripples free, and fault-tolerant capability. In addition, performance indices and Total Harmonic Distortions (THD) are also calculated to verify the robustness of the designed controller.

2016 ◽  
Vol 10 (8) ◽  
pp. 1
Author(s):  
Faraz Chamani ◽  
Mohammad Satkin

Wind energy is one of the extraordinary sources of renewable energy due to its clean character and free availability. With increase in wind power penetration, the wind farms are directly influencing the power systems. The majority of wind farms are using variable speed wind turbines equipped with doubly fed induction generators (DFIG) due to their advantages over other wind turbine generators (WTGs). Therefore, the analysis of wind power dynamics with the DFIG wind turbines has become a very important research issue, especially during transient faults. In this article, a controller is provided to control the active and reactive power of a wind system equipped with doubly fed induction generator. The generator is connected to the grid by a back to back converter that gets benefit from control system known as single periodic controller. Grid and generator side converters respectively control the generator speed and reactive power using proposed controller. In order to increase the accuracy of controller, we optimized its PI parameters using genetic optimization algorithm. Finally, simulation results conducted by the MATLAB software are shown. The results of simulation gained through this system, show the capability of proposed controller under error conditions for controlling active and reactive power and also elimination of harmonics caused by non-linear load.


Sign in / Sign up

Export Citation Format

Share Document