Simulation of intermediate impedance type differential bus-bar protection for marine power system

Traditional time and current principle is not competent for the effective protection of modern power system of large vessels,especially the integrated power system,so it's necessary to study new protecting method.Using the ratio check differential current protection method for terrestrial electric network for reference,the intermediate impedance bus differential protection of the simplified vessel power system of one single generator with pure resistance load was simulated in PSCAD/EMTDC and then experimented.The simulative model of intermediate impedance bus differential protective system for vessel ring network was constructed with specific simulation and analysis.The research shows that the intermediate impedance bus differential protection method can distinguish internal and external faults effectively,and the protecting actions are accurate and reliable.So this method is capable for the effective protection of large vessel power system.