The 6-35kV fully insulated tubular busbar developed jointly by our company and well-known colleges and universities has reached the domestic leading level through the new design, simulation calculation and optimization of various parameters of the intercepting copper tube, insulation and shielding materials, the use of special processes and advanced molding technology to produce large-capacity, maintenance-free, energy-saving composite solid insulated busbar systems with current levels of 630-2000-6300-16000A.