Capacitor Allocation in Unbalanced Distribution System under Unbalances and Loading Conditions

It is well known fact that distribution systems can operate under unbalanced loading conditions, means that the distribution system planner have to account for any unbalances in the system for reliable operation of the system. In this paper optimal sizes and locations of capacitors is determined using Index Vector method in unbalanced radial distribution system (ubds). In this paper two types of load unbalances and different loading conditions are considered to investigate its impact on optimal capacitor sizes and locations. The main objective of this paper is:
• Finding optimal size and locations of capacitors in ubds.
• Impact of different loading conditions (low, medium and high loading) on optimal placement of capacitors in ubds is evaluated.
• Impact of type-A and type-B unbalances on voltage profile, voltage unbalance, total power losses and cost of energy losses in ubds is determined.
• Impact of type-A and type-B unbalances on optimal capacitor allocation problem is addressed.
• Impact of realistic load model as ZIP load model has been considered in optimal capacitor placement problem.
• Computing required amount of capacitive reactive power to minimise total power losses and improve voltage profile under different load unbalances, different loading conditions and realistic ZIP load model.