A logic protection program design of urban distribution network

The traditional protection of urban distribution network has series of shortcomings such as the difficulty of coordination between protections, the large scope of blackout area and a long time for fault removing. Considering above situation, the paper presents a logic protection of urban distribution net work. Based the location in the distribution network, the switches are classified with which the protection action criterion is given. Combined with the actual characteristics of urban distribution network, the logic protection program is designed. The analysis of example verifies the effectiveness of the program.