A Pilot Protection Method for Active Distribution Networks Based on Protected Line Model

After Distributed Generations were connected to the distribution network on a large scale, the traditional single-ended radial distribution network structure became an active distribution network structure, which affected the sensitivity and reliability of traditional protection methods. Therefore, a new pilot protection method for active distribution network based on the protected line model is proposed in this paper, which determines whether the protected line model is integrity according to whether the waveforms are similar. The protection units on both sides of the line compare the waveform similarity between the respective measured voltages and the referenced voltages, then compare the fault location judgment results on both sides, and then make an accurate judgment on whether the protected line has internal or external faults. Finally, the active distribution network model was built in PSCAD/EMTDC simulation software. The simulation results show that the method proposed in this paper can accurately identify internal and external faults, has high reliability and good applicability, and is less affected by noise.