Application of Integrated Series Compensator in Damping Power Oscillations in Standalone Microgrids

This paper is concerned with power oscillation damping in standalone microgrids (MGs) using an integrated series compensator. Power oscillation is the result of dynamic interaction between generating units and/or loads in a power system, which results in increased losses, power quality degradation, and momentary overloading of the converters used in converter-based grid-connected microsources (MSs) in MGs. Designing an MS controller to mitigate these oscillations is not straightforward as other performance criteria may need to be compromised. The proposed structure employs a small series compensator to mitigate the oscillations. In this paper, the dependence of power/frequency variation is analytically shown. It is explained how by introduction of a series voltage, this dependence can be minimized. The derivation of the small-signal model used for eigenvalue analysis is briefly explained. To validate the modeling and show the performance and robustness of the proposed controller, time-domain simulations are used. Discussions on the size of the proposed compensator and also on using different control parameters are presented.