Multi-objective approach for optimal location of TCSC using NSGA II

This paper presents a novel approach to find optimum locations and sizes of TCSCs (Thyristor controlled Series Compensator) in transmission system. The approach comprises two main parts. In the first part, a mixed continuous-discrete multi-objective optimization problem is formulated in which TCSCs locations and sizes are the variables. The second part develops an optimization method based on NSGA II (Non-dominated Sorting Genetic Algorithm) to solve the problem. The outcome will be a set of possible solutions from which the most desirable, based on any nominated criteria, can be selected in a systematic manner. The proposed approach has been successfully tested on IEEE 30 bus system to find the optimal locations and sizes of TCSC devices. The obtained results show that with the allocation of TCSC devices determined by the proposed method, the security margin expressed in terms of power flow steady-state operation is increased in both normal state and critical contingencies while the available transmission capacity is enhanced.