Optimal sizing of FACTS controller through hybrid metaheuristic algorithm for static security enhancement in transmission power systems

• The New Voltage Stability Pointer (NVSP) was optimized to select best locations for FACTS devices’ placement. • The study proposed hybrid Dingo Optimization (DOA) and Firefly Algorithm (FA) to solve reactive power flow problem. • The DOA-FA generates three search agents for the overall stability enhancement of the power network. • The global best search was selected from the DOA-FA search agents based on the grid constraints. This study employs FACTS controller to address the reactive power flow problems and ensures adequate congestion management in the power grid. This is with a view to reducing total transmission power loss, enhancing voltage profile and maximizing the reactive power loadability. The optimal locations of the FACTS device were obtained through the maximum reactive power loadability via the analytical approach- new voltage stability pointer (NVSP). The sizing of the FACTS controller was optimized by leveraging on the combined strength of firefly algorithm (FA) and Dingo Optimization Algorithm (DOA). The effectiveness of the proposed model was validated with IEEE 30-bus and IEEE 57-bus test systems in MATLAB environment. The optimized NVSP results predicted three locations for possible placement of FACTS devices. Thereafter, the search agents of DOA-FA were reduced to three - best, ith, and nth - based on their fitness factor for each optimized NVSP location. The overall best search agent and optimized NVSP location for IEEE 30-bus and IEEE 57-bus test systems were identified. The corresponding total active power losses reductions of the IEEE 30- bus and IEEE 57-bus systems after the FACTS placement stands at 14.18 % and 19.95 %, respectively, under steady-state operation.