Two-phase liquid-cooled electrical power apparatus

A two-phase liquid-cooled system, comprising:

• first and second devices that generate heat at first and second surfaces, respectively, by passing electrical current through the first and second surfaces, said first and second devices designed to operate at different first and second operating temperatures;
• a first cooling circuit including a first closed-loop fluid path in which a first engineered liquid selected from fluorinated ketones (FKs), hydrofluoroethers (HFEs), perfluorocarbons (PFCs), hydrofluorocarbons (HFCs), perfluorohexans (PFHs), perfluoropolyether (PFPEs) and chlorofluorocarbons (CFCs) is continuously recirculated, a first portion of the fluid path is integrated with the first surface inside the first device, wherein the first engineered liquid is recirculated over and absorbs sufficient heat directly from the first surface to evaporate at a first phase transition temperature within the first portion of the fluid path inside the first device to cool the first surface and hold the operating temperature at the first surface at or near the first phase transition temperature;
• a second cooling circuit including a second closed-loop fluid path in which a second engineered liquid selected from FKs, HFEs, PFCs, HFCs, PFHs, PFPEs and CFCs is recirculated, a second portion of the fluid path is integrated with the second surface inside the second device, wherein the second engineered liquid is continuously recirculated over and absorbs sufficient heat directly from the second surface to evaporate at a second phase transition temperature within the second portion of the fluid path inside the second device to cool the second surface and hold the operating temperature at the second surface at or near the second phase transition temperature;
• wherein said first and second engineered liquids exhibit different first and second phase transition temperatures and different heats of vaporization, wherein said second phase transition temperature is at least 30° C. higher than said first phase transition temperature;
• a heat barrier positioned between the first and second devices' first and second surfaces;
• first and second electrical inline insulators positioned in the first closed-loop fluid path on opposite sides of the first device;
• third and fourth electrical inline insulators positioned in the second closed-loop fluid path on opposite sides of the second device;
• wherein the first and second closed-loop fluid paths configure the two-phase liquid-cooled system to be orientation independent.