Control of a STATCOM-assisted self-excited induction generator-based WECS feeding non-linear three-phase and single-phase loads

• Published in: IET power electronics 2019-04, Vol.12 (4), p.829-839
• Main Authors: Satpathy, Aradhya Sambhu, Kastha, Debaprasad, Kishore, Krishna
• Format: Article
• Language: English
• Subjects: adjustable VAR; asynchronous generators; fixed capacitor bank; harmonic compensation technique; harmonic distortion; harmonic‐free voltage; independent control; load demand; load voltage total harmonic distortion; nonlinear three‐phase; pitch control strategies; power generation control; power grids; Research Article; SEIG terminal voltage; self‐excited induction generator‐based wind energy conversion systems; similar controllers; single‐phase loads; stand‐alone loads; STATCOM DC‐link voltage; STATCOM‐assisted self‐excited induction generator‐based WECS; state feedback; state feedback‐based control scheme; static compensator; static VAr compensators; transient load voltage; VAR demand; voltage control; wind power plants; wind turbine pitch angle control; wind turbines
• ISSN: 1755-4535; 1755-4543; 1755-4543
• DOI: 10.1049/iet-pel.2018.5482

Self-excited induction generator (SEIG)-based wind energy conversion systems (WECS) are very popular for supplying stand-alone loads at remote sites. The SEIG needs adjustable VAR to regulate its terminal voltage and frequency. Usually, a combination of a static compensator (STATCOM) and a fixed capacitor bank is used to meet this VAR demand. Here, a state feedback-based control scheme is proposed to achieve independent control of the STATCOM DC-link voltage and the SEIG terminal voltage. Further, to ensure harmonic-free voltage at the SEIG terminal while supplying non-linear three-phase or single-phase loads, a harmonic compensation technique is also developed. The wind turbine pitch angle control is utilised to regulate the frequency of the SEIG terminal voltage. The combined action of the proposed voltage control and pitch control strategies ensures that the load voltage and frequency are maintained at their respective rated values with very low harmonic distortion irrespective of variation in the wind speed and load demand. The performance of the proposed controllers (in terms of transient load voltage and frequency deviations and load voltage total harmonic distortion), as verified on a laboratory prototype, are found to be superior to that of similar controllers proposed in the literature.