Fault location and reclosing scheme of DC distribution network based on parallel module

Due to the frequent occurrence of transient faults on overhead lines, the use of DC reclosing strategy can effectively improve its power supply reliability. However, when the DC grid coincides with a permanent fault, it will cause a secondary impact problem, endangering system operation and equipment safety. A fault location and reclosing scheme of DC distribution network based on parallel module is proposed. The parallel module consists of an energy absorption module and an energy storage module. The energy absorption module cooperates with the hybrid MMC to collect the residual energy of the current-limiting reactor and the line reactance. In addition, the energy storage module will also be connected to the absorption capacitor of the energy absorption module to charge it, so as to prevent the voltage traveling wave amplitude emitted by the absorption capacitor from being too low during the fault reclosing judgment, which will affect the judgment result. At the same time, using the principle of traveling wave ranging, the scheme also has the function of fault location. Finally, the simulation results prove that the method is effective and feasible.