State-space control for LCL filters
Conference article in proceedings
Proceedings of the 11th IEEE Energy Conversion Congress and Exposition, ECCE 2019, IEEE Energy Conversion Congress and Exposition
AbstractThis paper deals with discrete-time state-space current control of converters equipped with an LCL filter. Either the converter or grid current is measured and the unknown states are estimated using a reduced-order observer. These two current measurement options are compared by means of analysis and experiments under strong and weak grid conditions. To provide the basis for the comparison, equal reference-tracking performance is designed for both cases under strong grid conditions. In weak grids, the converter current measurement provides faster reference tracking, faster disturbance rejection, and better resonance damping in the case of the studied system where the LCL-filter resonance frequency is below the critical frequency.
Grid converter, LCL filter, Reduced-order observer, State-space current control, Weak grid
Rahman , F M M , Kukkola , J , Pirsto , V , Routimo , M & Hinkkanen , M 2019 , State-space control for LCL filters : Comparison between the converter and grid current measurements . in Proceedings of the 11th IEEE Energy Conversion Congress and Exposition, ECCE 2019 . IEEE Energy Conversion Congress and Exposition , IEEE , pp. 1491-1498 , IEEE Energy Conversion Congress and Exposition , Baltimore , Maryland , United States , 29/09/2019 . https://doi.org/10.1109/ECCE.2019.8913204