With a large number of distributed power generations connected to the distribution network

the distribution network has gradually transformed into a multi-source and multi-terminal network

and the requirements for relay protection performance are increasing. Current differential protection is suitable for the problem of multi-source network failure in distribution networks

but differential protection relies on fibre channel

which has problems such as high cost and difficult laying

which is difficult to promote and use. This paper proposes a distribution network differential protection scheme based on 5G communication

which aims to replace optical fiber by using the advantages of low latency and low cost of 5G communication and improve the practicality of differential protection of distribution network. To solve the problem of communication delay and delay jitter

an improved dynamic time programming (DTW) algorithm was introduced. Aiming at the shortcomings of traditional DTW algorithms

such as large overhead

algorithm accuracy and efficiency limited by sequence amplitude difference

and empirical selection of parameters

the global path constraint strategy

data standardization strategy and particle swarm optimization strategy are proposed to be improved. Simulation results show that the differential protection method of distribution network based on 5G communication and improved DTW is selective and fast

and can be reliably operated in different scenarios.