Title :
Implementing Virtual Inertia in DFIG-Based Wind Power Generation
Author :
Arani, Mohammadreza F. M. ; El-Saadany, Ehab F.
Author_Institution :
Dept. of Electr. & Comput. Eng., Univ. of Waterloo, Waterloo, ON, Canada
Abstract :
Although wind power as a renewable energy is assumed to be an advantageous source of energy, its intermittent nature causes difficulties especially in the islanding mode of operation. Conventional synchronous generators can help to compensate for wind fluctuations, but the slow behavior of such systems may result in stability concerns. Here, the virtual inertia method, which imitates the kinetic inertia of synchronous generator, is used to improve the system dynamic behavior. Since the proposed method focuses on short-term oscillations and incorporates no long-term power regulation, it needs no mass storage device. Thus, the method is economical. To prevent any additional cost, the rotating mass connected to the DFIG shaft or a super-capacitor connected to the DC-link of a back-to-back inverter of a wind power generator could be used. The concept and the proposed control methods are discussed in detail. Eigen-value analysis is used to study how the proposed method improves system stability. The advantages and disadvantages of using DFIG rotating mass or super-capacitor as the virtual inertia source are compared. The proposed approach also shows that while virtual inertia is not incorporated directly in long-term frequency and power regulation, it may enhance the system steady-state behavior indirectly. A time domain simulation is used to verify the results of the analytical studies.
Keywords :
asynchronous generators; frequency control; power control; power generation control; supercapacitors; wind power plants; DFIG rotating mass; control method; doubly fed induction generator; egenvalue analysis; islanding mode operation; kinetic inertia; long erm frequency regulation; power regulation; supercapacitor; system stability; virtual inertia method; virtual inertia source; wind power generation; Frequency control; Generators; Mathematical model; Stability analysis; Wind power generation; DFIG; DG; islanding; microgrid; rotating mass; super-capacitor; virtual inertia; wind power;
Journal_Title :
Power Systems, IEEE Transactions on
DOI :
10.1109/TPWRS.2012.2207972