A two level hybrid GA/SLP for FACTS allocation problem considering voltage security

Abstract

A two level hybrid genetic algorithm/successive linear programming (GA/SLP) method is presented to solve the multi-transition states voltage stability constrained VAR planning problem, which is formulated as mixed-integer non-linear programming problem. In the first level, the GA is employed to select the candidate sites and VAR amount of the FACTS devices to be installed in the system. These candidate allocations are passed to normal and contingency states in the second level, where the SLP is used to solve the non-linear operation problems associated with every state. The objective function is to minimize the sum of installation costs and operating costs under normal and contingency states, which include costs of load shedding, other emergency controls, and the expected voltage collapse cost. Two versions of the GA algorithms ‘simple genetic algorithm and modified genetic algorithm’ are implemented to show the feasibility of the proposed method. The proposed method has been applied on the AEP-14 bus system as well as IEEE-57 bus system to demonstrate its effectiveness.