Double-Frame Current Control with a Multivariable PI Controller and Power Compensation forWeak Unbalanced Networks
DOI:
https://doi.org/10.5170/CERN-2015-003.97Keywords:
Asymmetric networks, weak networks, PLL, double frame control, multivariable PI control, power theory.Abstract
The handling of weak networks with asymmetric loads and disturbances implies the accurate handling of the second-harmonic component that appears in an unbalanced network. This paper proposes a classic vector control approach using a PI-based controller with superior decoupling capabilities for operation in weak networks with unbalanced phase voltages. A synchronization method for weak unbalanced networks is detailed, with dedicated dimensioning rules. The use of a double-frame controller allows a current symmetry or controlled imbalance to be forced for compensation of power oscillations by controlling the negative current sequence. This paper also serves as a useful reminder of the proper way to cancel the inherent coupling effect due to the transformation to the synchronous rotating reference frame, and of basic considerations of the relationship between switching frequency and control bandwidth.Downloads
Published
2016-02-03
Issue
Section
Article
License
Authors who publish with this publication agree to the following terms:
- CERN retains copyright and publishes the work licensed under the Creative Commons Attribution License 4.0 that allows others to share the work with an acknowledgement of the work's authorship and initial publication in this series.
- Authors are able to enter into separate, additional contractual arrangements for distribution of the published version of the work (e.g., post it to an institutional repository or publish it in a book), with an acknowledgement of its initial publication in this series.
- Authors are permitted and encouraged to post their work online (e.g., in institutional repositories or on their website) prior to and during the submission process, as it can lead to productive exchanges, as well as earlier and greater citation of published work (See The Effect of Open Access).