Switching operation decision making by using Petri-Net approach for power distribution systems

In this paper, the artificially intelligent Petri-Net is applied to find optimal switching operations for service restoration and feeder loading balancing of distribution systems. For contingencies, the Petri-Net model with an inference mechanism is derived to provide the optimal load transfer among distribution feeders after the fault location has been identified and isolated. For normal operation, the load balancing among distribution feeders is obtained by the Petri-Net model to enhance the operation efficiency of distribution systems. To represent the load behavior of distribution systems more practically, the load profiles of distribution feeders are derived by load survey study. Load flow analysis is then performed to solve the hourly current flows of all line switches. The switching operation, which will result in the loading balance among distribution feeders, is derived by the Petri-Net model according to the loading cost to the distribution system. To demonstrate the effectiveness of the proposed methodology, a sample distribution system has been selected for computer simulation. It is found that the proposed Petri-Net algorithm can enhance fault restoration with proper load transfer and improve feeder load balance for distribution systems by considering the load characteristics of the service customers.