Applicaiton of protection strategy base on the rate of current change in AC/DC distribution network

In order to solve the problem of insufficient operation reliability and protection-selected ability of Modular Multilevel Converter (MMC) converter in Alternating Current (AC)/Direct Current (DC) power distribution system under the short circuit between DC electrodes, this paper studies the protection strategy under the fault of AC/DC power distribution system, and introduces the relay protection strategy based on the rate of current change, which improves the sensitivity of fault characteristics and the accuracy of protection action under the reaction fault state. In this paper, a simulation test based on PSCAD/EMTDC platform is carried out based on the application case of the inter-electrode short-circuit fault in the four-terminal loop AC/DC hybrid distribution system. The simulation results verify the accuracy and effectiveness of the action behavior of the protection policy under the faults within and out of the system, and provide an effective theoretical basis and technical support for improving the operational reliability of AC/DC hybrid power distribution system.