Abstract: The subject of the present application is a cover for distribution transformer filled with a dielectric liquid, equipped with electronic device integrated with the cover which is applied for transmission and distribution of electric energy. The cover is characterized in that the electronic device is immersed in the dielectric liquid filling a cooling compartment fixed on the cover; the cooling compartment has side walls, a top wall and a bottom wall which bottom wall is matched in the window made in the cover and the bottom wall forms a thermal barrier between the interior of the electric power device and the interior of the cooling compartment and the both interiors of the cooling compartment and of the electric power device are hermetically closed together.

Abstract: The subject of the application is a power electronic tap changer module for transformer using power electronic elements connected to sections of a primary winding of the transformer. The power electronic tap changer module is equipped with valves having a pair of a thyristor or transistors connected with a controller and the valves are connected in series with the fuses, respectively. The module is equipped with an additional oversized tap line having an oversized valve rated for short circuit current, which valve is connected with an overvoltage triggering circuit. The oversized valve is equipped with a pair of thyristor or transistors connected with a thermally protected voltage suppressing device.

Abstract: The subject of the application is a power electronic tap changer module for transformer using power electronic elements connected to sections of a primary winding of the transformer. The power electronic tap changer module is equipped with valves having a pair of a thyristor or transistors connected with a controller and the valves are connected in series with the fuses, respectively. The module is equipped with an additional oversized tap line having an oversized valve rated for short circuit current, which valve is connected with an overvoltage triggering circuit. The oversized valve is equipped with a pair of thyristor or transistors connected with a thermally protected voltage suppressing device.

Abstract: The subject of the present application is a cover for distribution transformer filled with a dielectric liquid, equipped with electronic device integrated with the cover which is applied for transmission and distribution of electric energy. The cover is characterized in that the electronic device is immersed in the dielectric liquid filling a cooling compartment fixed on the cover; the cooling compartment has side walls, a top wall and a bottom wall which bottom wall is matched in the window made in the cover and the bottom wall forms a thermal barrier between the interior of the electric power device and the interior of the cooling compartment and the both interiors of the cooling compartment and of the electric power device are hermetically closed together.