DG Integrated Approach for Service Restoration Under Cold Load Pickup

The additional power demand caused by cold load pickup (CLPU) condition restricts the simultaneous restoration of all the loads of a network due to excessive loading on the network elements and violation of limits. Therefore, step-by-step restoration is the most adopted approach. However, it requires long time for the complete restoration. The main cause of CLPU problem is the loss of diversity amongst the loads which causes the enduring phase of CLPU condition. The conservation of load diversity reduces the demand during restoration. In the proposed approach, the diversity is conserved by using distributed generation (DG) for quick restoration and the reduction of additional power demand caused by CLPU condition. The capacity required for DG is evaluated on the basis of the required additional power demand and the load-diversity preserved. The proposed approach utilizes the genetic algorithm for determination of the optimal size and location of the required DG. The approach is demonstrated on a 33-bus, 12.66-kV primary distribution network.