Open AccessPI‐based controller for low‐power distributed inverters to maximise reactive current injection while avoiding over voltage during voltage sags
Author(s) -
Miret Jaume,
Garnica Miguel A.,
Castilla Miguel,
Garcia de Vicuña Jose Luis,
Camacho Antonio
Publication year - 2019
Publication title -
iet power electronics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.637
H-Index - 77
eISSN - 1755-4543
pISSN - 1755-4535
DOI - 10.1049/iet-pel.2018.5071
Subject(s) - grid code , ac power , voltage sag , controller (irrigation) , voltage , overvoltage , control theory (sociology) , engineering , inverter , power (physics) , distributed generation , low voltage ride through , voltage optimisation , grid , computer science , electrical engineering , control (management) , power quality , renewable energy , physics , agronomy , quantum mechanics , biology , geometry , mathematics , artificial intelligence
In the recently deregulated power system scenario, the growing number of distributed generation sources should be considered as an opportunity to improve stability and power quality along the grid. To make progress in this direction, this work proposes a reactive current injection control scheme for distributed inverters under voltage sags. During the sag, the inverter injects, at least, the minimum amount of reactive current required by the grid code. The flexible reactive power injection ensures that one phase current is maintained at its maximum rated value, providing maximum support to the most faulted phase voltage. In addition, active power curtailment occurs only to satisfy the grid code reactive current requirements. As well as, a voltage control loop is implemented to avoid overvoltage in non‐faulty phases, which otherwise would probably occur due to the injection of reactive current into an inductive grid. The controller is proposed for low‐power rating distributed inverters where conventional voltage support provided by large power plants is not available. The implementation of the controller provides a low computational burden because conventional PI‐based control loops may apply. Selected experimental results are reported in order to validate the effectiveness of the proposed control scheme.