Abstract

Ensuring continuous, economical and quality power supply to customers is the primary objective of suppliers. This implies quick restoration of supply in case of faults, to maximum possible load in minimum time with minimum loss. Power quality and network loss can be improved by providing reactive power compensation using capacitors. This paper proposes a new method for system reconfiguration and fault restoration of a distribution network. The approach is applicable to both single and multiple fault cases. The hierarchy of the methodology is downward from the feeder to the bus level. Additionally, an iterative method is proposed for evaluating capacitor size and location by calculating the loss sensitivity index (LSI) of the buses. Compensation is provided to the initial network. Faults are then simulated and the effect of the existing compensation after fault restoration using the proposed method is studied. Later, a new compensation scheme is derived by altering the original scheme. Suitable compensation solution can be decided based on either minimum loss or cost restraints. The proposed method is applied to a 44-bus distribution network of R. K. Nagar, KPTCL, Karnataka, India. Comparison of the network parameters and results after fault restoration without compensation, with initial compensation and after applying the new compensation scheme shows the method is very effective in responding to faults, in practical time periods.

Key words: Single fault, multiple faults, feeder fault, network line fault, reconfiguration, supply restoration, load shedding, capacitor placement