Patent ID: 11869881
Assignee: ROLLS-ROYCE DEUTSCHLAND LTD & CO KG
Field: Semiconductors (Electrical engineering)
Classification: CPC H  B  Y | IPC B  H

Claim 16:
17. An electrical propulsion unit for an aircraft, the electrical propulsion unit comprising:
an electric motor; and
an AC-DC power electronics converter configured as an inverter and arranged to supply current to a winding of the electric motor,
wherein the AC-DC power electronics converter comprises:
a converter commutation cell comprising a power circuit and a gate driver circuit, the power circuit comprising at least one power semiconductor switching element and at least one capacitor; and
a multi-layer planar carrier substrate defining an x-y direction parallel to a planar surface of the multi-layer planar carrier substrate and a z-direction perpendicular to the x-y direction, the multi-layer planar carrier substrate comprising a plurality of electrically conductive layers extending in the x-y direction and at least one electrical connection extending in the z-direction,
wherein each power semiconductor switching element of the at least one power semiconductor switching element is comprised in a power semiconductor prepackage,
wherein each power semiconductor prepackage comprises one or more power semiconductor switching elements embedded in a solid insulating material,
wherein each power semiconductor prepackage further comprises at least one electrical connection extending in the z-direction from at least one terminal of each power semiconductor switching element of the one or more power semiconductor switching elements through the solid insulating material to an electrical connection side of the power semiconductor prepackage,
wherein at least one terminal of each power semiconducting switching element of the one or more power semiconductor switching elements of the power semiconductor prepackage is connected to at least one electrically conductive layer of the plurality of electrically conductive layers of the multi-layer planar carrier substrate at the electrical connection side of the power semiconductor prepackage,
wherein the AC-DC power electronics converter further comprises a heat sink configured to remove heat from the power semiconductor prepackage, the heat sink being spaced apart in the z-direction from a heat removal side of the power semiconductor prepackage so as to define a gap between the heat removal side of the power semiconductor prepackage and a thermal connection side of the heat sink, and
wherein a size in the z-direction of the gap between the heat removal side of the power semiconductor prepackage and the heat sink is configured to provide a converter parameter η that is greater than or equal to 100 kW/m3K, η being defined as a heat transfer coefficient between the heat removal side of the power semiconductor prepackage and a cooling medium of the heat sink divided by the size in the z-direction of the gap between the heat removal side of the power semiconductor prepackage and the heat sink.