Distribution Automation (DA) is part of today's evolution of the distribution system. Many utilities already have some Distribution Automation applications (e.g., remote controlling of feeder switches and breakers, automatic reconfiguration, fault detection, fault location, voltage and reactive power control, Advanced Metering Infrastructure (AMI), etc.) and the trend is undeniable and expanding.

Effect of Distribution Automation on Protective Relaying

This paper presents a new approach to minimize power losses and the associated dollar costs in the distribution system. The approach is based on direct load control (DLC) of residential electric water heaters and on increasing the storage capacity of the water heaters under DLC. An optimization algorithm based on the Lagrange multiplier method has been developed to minimize the power system distribution losses. The objective function is obtained by the summation of the system peak real power loss cost, annual energy loss cost, and the cost associated with purchasing and installing the additional water heaters used for DLC. The objective function subject to a number of constraints is solved to obtain the optimal number and location of water heaters under DLC. The proposed method is applied to a main feeder with laterals.

Direct load control for reducing losses in the main and laterals of distribution systems

Distribution system loss reduction has been grossly neglected by most electricity utilities even though it contributes to no less than 75 per cent of the total system losses. Existing methods of loss reduction involve enormous capital cost and extensive rehabilitation to the existing distribution reticulation and are hence not very practical, compounded with the problem of coping with the high and dynamic load growth in most developing countries. The paper looks into techniques of selecting and operating the distribution system, with minimum or no physical change in the present distribution reticulation to reduce losses. It proposes that the existing distribution network be operated in 'island groups' by paralleling selected feeders into an island.

K.L. Lo

Papers

Loss minimisation using islanding technique for district of Klang, Malaysia