Optimal Power Flow with TCSC and TCPS Modeling Figure 1. Circuit model of TCSC connected between i th bus and j th bus global best solution. The new PSO algorithms (TRPSO and CRPSO) are implemented to mini- mize the generator fuel cost in optimal power flow with multiple type FACTS devices. Modi- fied IEEE 30-bus system with single and multiple TCSC and TCPS devices in different locations are presented to show the algorithms' flexibility and reliability towards the convergence. The results obtained by the proposed PSO algorithms are compared to the results of PSOIWA and RGA P ij = V i 2 g ij - VV j ( g ij cos ij + b ij sin ij ) i Q ij = - i 2 b ij - VV j ( g ij sin ij - b ij cos ij ) V i r ij r ij 2 + ( x ij - x c ) 2 (1) (2) Where b ij = g ij = - x c ) 2 and ( x ij r 2 + x - x