The state develops new infrastructure vigorously, and UHV transmission projects have a major demand for silicon carbide power devices. Its main application scenarios in the smart grid include: HVDC converter valves, flexible HVDC converter valves, flexible AC transmission devices, HVDC circuit breakers, power electronic transformers and other devices. The smart grid has the following characteristics: powerful self-regulation ability, which can automatically detect and analyze faults, realize fault isolation and system self-recovery; Economy, to achieve rational allocation of resources, improve energy utilization efficiency, reduce power loss, reduce investment costs and operation and maintenance costs; Strong compatibility, can accommodate centralized power generation, distributed generation and other types of power sources, to meet the diverse power needs of users.