A Stochastic Optimization Model for Distributed Static Series Compensator Allocation to Mitigate Transmission Congestion

Due to the integration of new power plants and renewable energy sources, the existing transmission system often experience congestion which increases the overall operating cost. Distributed static series compensator (DSSC) is a type of distributed flexible AC transmission systems (D-FACTS) which can effectively mitigate transmission congestion by phase shifting. This study proposes a scenario-based stochastic optimization model to optimally allocate DSSC modules in transmission systems with an objective of minimizing the overall operating cost considering investment limits, and studies the effectiveness of DSSC in transmission congestion mitigation. The model was implemented on a modified RTS-96 test system, and up to 19.98% of savings in operating cost was achieved using optimally located DSSC modules, which was higher than using conventional FACTS and DSSC modules with pre-determined locations. This validates the effectiveness of the model in terms of optimally allocating DSSC to mitigate transmission congestion.