A heat dissipation structure comprises a flexible substrate, a graphite sheet, and a heat insulating material. The flexible substrate comprises a first surface and a second surface facing away from the first surface. The graphite sheet is connected to the second surface. At least one containing cavity is defined on an interface between the second surface and the graphite sheet. The heat insulating material is filled in the at least one containing cavity to form a heat insulating structure.

The present disclosure relates to an air-to-air through-wall bushing including a conductor, insulation surrounding the conductor, a ventilation inlet at a first end of the bushing, and a ventilation outlet at a second end of the bushing. The bushing is arranged through a wall and a pressure difference between a first pressure on a first side of the wall and a second pressure on a second side of the wall is provided The inlet and outlet allow cooling air to pass through a ventilation channel within the bushing driven by the provided pressure difference.

The present disclosure relates to an air-to-air through-wall bushing including a conductor, insulation surrounding the conductor, a ventilation inlet at a first end of the bushing, and a ventilation outlet at a second end of the bushing. The bushing is arranged through a wall and a pressure difference between a first pressure on a first side of the wall and a second pressure on a second side of the wall is provided The inlet and outlet allow cooling air to pass through a ventilation channel within the bushing driven by the provided pressure difference.

A high-voltage bushing includes a conductive rod and an air cooling device. The conductive rod has an air channel therein, and the air channel includes an air inlet and an air outlet. The air cooling device includes at least one fan, and the fan is configured to output air flow, so as to blow the air flow into the air channel through the air inlet.