By Topic

Control of a Cascade STATCOM With Star Configuration Under Unbalanced Conditions

Sign In

Cookies must be enabled to login.After enabling cookies , please use refresh or reload or ctrl+f5 on the browser for the login options.

Formats Non-Member Member
$33 $13
Learn how you can qualify for the best price for this item!
Become an IEEE Member or Subscribe to
IEEE Xplore for exclusive pricing!
close button

puzzle piece

IEEE membership options for an individual and IEEE Xplore subscriptions for an organization offer the most affordable access to essential journal articles, conference papers, standards, eBooks, and eLearning courses.

Learn more about:

IEEE membership

IEEE Xplore subscriptions

2 Author(s)
Qiang Song ; Dept. of Electr. Eng., Tsinghua Univ., Beijing ; Wenhua Liu

A control scheme for star-connected cascade static synchronous compensators (STATCOMs) operating under unbalanced conditions is proposed. The STATCOM is assumed to be connected to an equivalent three-phase star-connected power supply. By selecting the line-to-neutral voltages of the equivalent power supply, zero average active power in each phase can be obtained under unbalanced compensation currents or unbalanced supply voltages. Furthermore, to implement a separate control for the three-phase dc-link voltages, the average active power in each phase can also be adjusted to a target value determined by the dc-link voltage control loop. Then, by forcing the converter neutral voltage to be equal to the counterpart of the equivalent power supply, the STATCOM can be decoupled into three single-phase systems and the line-to-neutral voltage of the equivalent power supply can be used as the input voltage to the corresponding phase leg. Accordingly, reference current tracking and dc-link voltage maintaining can be simultaneously achieved under unbalanced conditions. The valid operating range of the star-connected cascade STATCOM under unbalanced conditions is also analyzed. The proposed control scheme has been tested using the power systems computer-aided design/electromagnetic transient in dc system (EMTDC) simulation results and the experimental results based on a 30-kVAr cascade STATCOM laboratory prototype are proposed.

Published in:

IEEE Transactions on Power Electronics  (Volume:24 ,  Issue: 1 )