1. The functional rooms of the equipment are isolated from each other, and they are divided into functional unit rooms, busbar rooms, and cable rooms, each with a relatively independent function; 2. The horizontal main busbar adopts a flat arrangement behind the cabinet to enhance the busbar's resistance to electrodynamic forces, ensuring the main circuit of the equipment possesses high short-circuit strength capability; 3. The extraction and insertion of functional units (drawers) are operated by levers, coupled with the use of rolling bearings, making the operation lightweight and reliable