Title :
Simple synchronisation technique for three-phase grid-connected distributed generation systems
Author :
Xiao-Qiang Guo ; Wei-Yang Wu
Author_Institution :
Dept. of Electr. Eng., Yanshan Univ., Qinhuangdao, China
Abstract :
Grid synchronisation is crucial for integration of renewable energy sources and distributed generation systems into the grid. Accurate and fast estimation of the fundamental positive sequence component is a necessity for synchronisation of three-phase distributed generation systems with the grid. In this study, a simple synchronisation technique based on the real-complex-coefficient filters is proposed. It has a very simple structure, and can directly estimate the fundamental positive and negative sequences under the distorted, unbalanced and offset conditions with no need of a phase-locked loop. Furthermore, the dc offset can also be extracted precisely. For optimising the steady-state and dynamic performance, a parameter tuning guidance is provided from the eigenvalue analysis point of view. In addition, a simple auxiliary unit is presented to remain its frequency-adaptive feature. Finally, experimental results based on a 32-bit fixed-point TMS320F2812 DSP verify the effectiveness of the proposed synchronisation method.
Keywords :
distributed power generation; eigenvalues and eigenfunctions; power filters; power grids; renewable energy sources; auxiliary unit; dc offset; distorted conditions; dynamic performance; eigenvalue analysis; fixed-point TMS320F2812 DSP; frequency-adaptive feature; fundamental positive sequence component; grid synchronisation; negative sequences; offset conditions; parameter tuning guidance; real-complex-coefficient filters; renewable energy sources; steady-state performance; three-phase grid-connected distributed generation systems; unbalanced conditions; word length 32 bit;
Journal_Title :
Renewable Power Generation, IET
DOI :
10.1049/iet-rpg.2011.0243