LAUSR

One major reliability concern regarding renewable energy resources connected in the vicinity of series-compensated power transmission lines or to weak power grids is subsynchronous resonance. A particular type of interaction known as subsynchronous control interaction (SSCI), with a purely electrical nature, has the potential to grow very rapidly and can cause severe damage to power grid infrastructure. This article proposes an additional damping controller that allows mitigating the SSCI expeditiously. The proposed damping loop provides a very large impedance at the synchronous frequency and very low impedance at the subsynchronous range. More importantly, it can be integrated into the control loop of the battery energy storage systems (BESS) without imposing a negative impact on the routine performance of the BESS. As BESSs are becoming more popular in power grids, thanks to their significant impacts on reliability and power quality, it is anticipated that the proposed approach will have a great implementation opportunity. Hence, the proposed mitigation solution is implemented in a hybrid plant and tested with a radial test system and a section of the Electric Reliability Council of Texas power grid under a variety of operating conditions. The results show the efficiency and robustness of the mitigation solution even under different frequencies of oscillation and larges disturbances.