Publication

Robust repetitive control of power inverters for standalone operation in DG systems

Journal Article (2020)

Journal

IEEE Transactions on Energy Conversion

Pages

237-247

Volume

35

Number

1

Doc link

https://doi.org/10.1109/TEC.2019.2948900

File

Download the digital copy of the doc pdf document

Abstract

Standalone operation of an inverted-based distributed generation unit is performed in voltage control mode. In this mode, it is important that the controller provides tracking and rejection of periodic signals. Strategies like Repetitive Control (RC) are well suited in the voltage control of power inverters. However, the robustness of repetitive controllers is importantly affected by the connected loads. The reason is that the load modifies the dynamics of the system where the design of the RC relies on. Having a low bandwidth action can reduce the problem but with the cost of degrading the voltage waveform and transient response. As an alternative, an H ∞ design is proposed for the RC of voltage source inverters. In this proposal the load is directly treated as an unstructured uncertainty. With this approach, the design procedure directly maximizes the robust stability margin of the system against load variations/uncertainty. Additionally, the analysis provides some insight about the design of the inverter LC filter. Experimental results show that a remarkable Total Harmonic Distortion and good transient response are obtained for a large variety of loads.

Categories

control theory.

Scientific reference

German A. Ramos, R. Isaza and R. Costa Castelló. Robust repetitive control of power inverters for standalone operation in DG systems. IEEE Transactions on Energy Conversion, 35(1): 237-247, 2020.