Switchgear is designed according to GB3906 and IEC298 standards, the whole is composed of cabinet and withdrawable parts (trolley), the cabinet structure is made of aluminum zinc plate or galvanized plate assembled by bolted connection, the switchgear is separated into a short circuit breaker room, busbar room, cable room and instrumentation room, all the metal components are reliably grounded, the compartments of the main circuit system have an independent pressure release channel, and a 10×60m ground busbar can be set up in the cable room. The main circuit system has independent pressure release channels in each compartment, and 10×60m ground busbar can be set in the cable room.