Study on the Transient Power Angle Characteristic of Doubly-Fed Induction Generator

Doubly-fed induction generator (DFIG) wind turbine has become a mainstream machine of wind generators in China. As the different operational characteristics between the DFIG and synchronous generator (SG), the large amount of DFIG-based wind generators installed in the grid may bring a series of impacts on the dynamic behaviors of power system. In order to study the DFIG transient characteristics on the condition of the voltage dips happening in the power system, a definition of the DFIG power angle is given and the effects of the converters on the DFIG power angle are discussed. On this basis, the transient angle characteristic of the DFIG is derived. The DFIG transient characteristics are performed by Matlab/Simulink software, the simulation results demonstrate that the DFIG has the resemble power angle characteristic of SG and prove the effectiveness of the derivation process, which lay a foundation for the study on the interactions between the DFIG and power system.

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Oscillation Damping for Wind Energy Conversion System with Doubly Fed Induction Generator Association with Synchronous Generator

Energies ◽

10.3390/en13195067 ◽

2020 ◽

Vol 13 (19) ◽

pp. 5067

Author(s):

Farag K. Abo-Elyousr ◽

Hossam S. Abbas ◽

Ali M. Yousef ◽

Nguyen Vu Quynh ◽

Ziad M. Ali ◽

...

Keyword(s):

Power System ◽

Energy Conversion ◽

Synchronous Generator ◽

Induction Generator ◽

Doubly Fed Induction Generator ◽

Rotor Speed ◽

Linear Quadratic ◽

Interconnected Power System ◽

Wind Energy Conversion ◽

Doubly Fed

The main purpose of this paper is to enhance the operation of renewable wind energy conversion (WEC) systems connected to power systems. To achieve this, we consider a linear quadratic Gaussian (LQG) control approach for regulating the effects of a WEC system with doubly fed induction generator (DFIG) on the synchronous generator (SG) rotor speed of the interconnected power system. First, we present the mathematical formulation of the interconnected power system comprises a single synchronous generator and a wind turbine with DFIG connected to an infinite bus bar system through a transmission line. We consider that the system is operated under various loading conditions and parameters variation. Second, a frequency damping oscillation observer is designed via Kalman filtering together with an optimal linear quadratic regulator to mitigate the impacts of the WEC system on the SG rotor speed. The performance of the developed interconnected power system is simulated using a MATLAB/SIMULINK environment to verify the effectiveness of the developed controller. In comparison with previously reported results, the proposed approach can stabilize the interconnected power system within 1.28 s compared to 1.3 s without the DFIG.

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Effect of Grid Faults on Dominant Wind Generators for Electric Power System Integration:A Comparison and Assessment

Energy Systems Research ◽

10.38028/esr.2021.03.0007 ◽

2021 ◽

pp. 70-78

Author(s):

M. M. Metwally ◽

M. K. Ratib ◽

M.M. Aly ◽

A.M. Abdel‑Rahim

Keyword(s):

Permanent Magnet ◽

Electric Power ◽

Synchronous Generator ◽

Induction Generator ◽

Doubly Fed Induction Generator ◽

Permanent Magnet Synchronous Generator ◽

Wind Generators ◽

Squirrel Cage ◽

Squirrel Cage Induction Generator ◽

Doubly Fed

In recent times, various types of wind generators have been linked to the power grids globally and the focus has been to control them to be more efficient and reliable. This study concisely discusses performance analysis, modeling, and assessment of different wind generators (permanent magnet synchronous generator, doubly-fed induction generator, squirrel cage induction generator), covering their benefits, drawbacks, and impact on the electric power systems. This comparison aims to guarantee that their technical and economic evaluations are comparable, allowing engineers to make a more informed decision about which generator is best suitable for their installation. Findings for the investigated wind generators lead to significant observations about their application fields, such as permanent magnet synchronous generator outperforms doubly-fed induction generator and squirrel cage induction generator, especially during grid disruptions; on the other hand, squirrel cage induction generator is simple and inexpensive.

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