Linear-quadratic regulator of torque and reactive power of a doubly fed induction generator operating in an unbalanced grid

2015 ◽  
Author(s):  
Mateusz Szypulski ◽  
Grzegorz Iwanski
Keyword(s):  
Reactive Power ◽  
Linear Quadratic Regulator ◽  
Induction Generator ◽  
Doubly Fed Induction Generator ◽  
Linear Quadratic ◽  
Doubly Fed ◽  
Unbalanced Grid

LQG Controller for the Control of Active and Reactive Power of DFIG Operating Under Inter-turn Short Circuit Fault

2020 ◽  
Vol 13 (3) ◽  
pp. 340-347
Author(s):  
Selam Karim ◽  
Allaoui Tayeb ◽  
Tadjine Mohamed
Keyword(s):  
Reactive Power ◽  
Short Circuit ◽  
Linear Quadratic Regulator ◽  
External Perturbation ◽  
Doubly Fed Induction Generator ◽  
Linear Quadratic ◽  
Linear Quadratic Gaussian ◽  
Doubly Fed ◽  
Motor Operation ◽  
Short Circuit Fault

Objective: This article presents a comparative study between the direct control for a Doubly- Fed Induction Generator (DFIG) in the healthy and faulty mode. Methods: First with classical IP controller then Linear Quadratic Gaussian (LQG) controller which propose an ensemble of Linear Quadratic Regulator and Kalman filter for the state estimation. The developed model of the machine allows the simulation of the inter-turn short circuit in the stator. The use of the LQG method provides very good performance for motor operation and robustness of the control law despite the external perturbation. The performance of the control is compared to a classical controller's PI. Results: The obtained results demonstrate that this type of controller allows the alleviation of the mechanical stress and it ensures good performances under fault, the continuity of this system is ensured. Conclusion: The simulation has been carried out using a MATLAB script and the results are presented.

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 ◽  
...  
Keyword(s):  
Wind Turbines ◽  
Reactive Power ◽  
Negative Impact ◽  
Voltage Source ◽  
Induction Generator ◽  
Doubly Fed Induction Generator ◽  
Grid Voltage ◽  
Active And Reactive Power ◽  
Doubly Fed ◽  
Unbalanced Grid

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.

scholarly journals Dynamic Modeling and Control of BDFRG under Unbalanced Grid Conditions

Energies ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 4297
Author(s):  
Taufik Taluo ◽  
Leposava Ristić ◽  
Milutin Jovanović
Keyword(s):  
Vector Control ◽  
Control Strategy ◽  
Reactive Power ◽  
High Reliability ◽  
Current Control ◽  
Induction Generator ◽  
Doubly Fed Induction Generator ◽  
Secondary Currents ◽  
Doubly Fed ◽  
Unbalanced Grid

The Brushless Doubly-Fed Reluctance Generator (BDFRG) is a potential alternative to the Doubly Fed Induction Generator (DFIG) in wind power applications owing to its reasonable cost, competitive performance, and high reliability. In comparison with the Brushless Doubly-Fed Induction Generator (BDFIG), the BDFRG is more efficient and easier to control owing to the cage-less rotor. One of the most preferable advantages of BDFRG over DFIG is the inherently better performance under unbalanced grid conditions. The study conducted in this paper showed that conventional vector control of the BDFRG results in excessive oscillations of the primary active/reactive power, electromagnetic torque, and primary/secondary currents in this case. In order to address such limitations, this paper presented a new control strategy for the unbalanced operation of BDFRG-based wind generation systems. A modified vector control scheme was proposed with the capability to control the positive and the negative sequences of the secondary currents independently, thus greatly reducing the adverse implications of the unbalanced supply. The controller performance has been validated by simulations using a 1.5 MW BDFRG dynamical model built upon the positive and negative sequence equations. The main benefits of the new control strategy are quantified in comparison with conventional PI current control design.

Sign in / Sign up

Export Citation Format

Share Document