Optimal Multi-Objective VAr Planning Using Accelerated Ant Colony and Analytical Hierarchy Process Methods

The aim of reactive power (VAr) planning is to provide the system with sufficient VAr sources to enable the system to be operated under economically conditions. The VAr planning problem is a constrained, multi-objective non-differentiable optimization problem. The VAr problem is first formulated as a multi-objective problem. This formulation considers different objective functions related to real power losses, investment cost of VAr sources, installation and maintenance cost, voltage deviation and security margin with equality and inequality constraints. Second the objective functions are weighted by analytical hierarchy process (AHP), so the multi-objective optimization problem is converted into single objective function. Third the weak bus and heavy load bus oriented criterions are used to determine the candidate buses for installing new VAr sources. Then an ant colony algorithm which is based on the foraging behavior of ants is developed to solve this problem. This proposed method has been applied on the modified IEEE 14 bus system