Fault-Tolerant Power Transformer Design and Method of Fabrication

A heat exchanger for a transformer system, wherein the heat exchanger is capable of circulating dielectric fluid as the dielectric fluid increases in temperature and expands within a transformer tank, wherein the heat exchanger comprises:

• a hollow panel comprising a first side and a second side,
• wherein the second side of the hollow panel is connected to the transformer tank at a plurality of ports,
• wherein heated dielectric fluid circulates into the heat exchanger from the transformer tank through a first port and cooled dielectric fluid exits the heat exchanger through a second port back to the transformer tank;
• wherein the hollow panel is capable of expanding in volume to contain electric fault energy that produces a sudden generation of gases which increases the pressure inside the heat exchanger, and
• wherein the heat exchanger comprises a plurality of constraints, said plurality of constraint being capable of minimizing deformation of the heat exchanger when the heat exchanger expands in volume.

A heat exchanger for a transformer system, wherein the heat exchanger is capable of circulating dielectric fluid as the dielectric fluid increases in temperature and expands within a transformer tank, wherein the heat exchanger comprises:

• a hollow panel comprising a first side and a second side,
• wherein the second side of the hollow panel is connected to the transformer tank at a plurality of ports,
• wherein heated dielectric fluid circulates into the heat exchanger from the transformer tank through a first port and cooled dielectric fluid exits the heat exchanger through a second port back to the transformer tank;
• wherein the hollow panel is capable of expanding in volume to contain energy resulting from a sudden generation of gases which increases pressure inside the heat exchanger, and
• wherein the heat exchanger comprises a preferred release notch on a lower edge of the hollow panel, wherein the preferred release notch comprises a wedge piece that is welded between a notched lower edge of the first side and the second side of the hollow panel, and wherein the wedge piece tapers to a tip at an upper edge of the preferred release notch between the first side and the second side,
• wherein when the dielectric fluid becomes heated and pressure inside the heat exchanger exceeds a rupture pressure of the heat exchanger, a controlled pressure release preferentially initiates at the upper edge of the preferred release notch of the heat exchanger, wherein the preferred release notch is configured to provide a progressive opening that can gradually wide as the pressure intensifies.