Optimal Placement of STATCOMs in Multi-infeed Power Electronic Systems for Small Signal Stability

The power electronic devices (PEDs) have small signal stability issues in weak grids. as high-controllability devices, the STATCOMs can be a potential choice to enhance the small-signal stability. However, how the location of STATCOMs influences the stability of a multi-infeed power electronic system (MIPES) has not been investigated. To quantify the STATCOMs’ location on the small signal stability for a structure-preserving MIPES, an eigenvalue-sensitivity-based method is proposed in this paper. The theoretical analysis shows that for a homogeneous MIPES, the STATCOMs’ location on the stability mainly depends on the network structure, PEDs’ capacities and STATCOMs’ location. Based on this, a metric is proposed for the optimal placement of STATCOMs in a MIPES to enhance the small signal stability. Simulation results verify the validity of this metric.