Abstract: An aircraft propulsion system includes at least first and second electrical generators, each being configured to provide electrical power to a respective first and second AC electrical network. The system further comprises at least first and second AC electrical motors directly electrically coupled to a respective AC network and coupled to a respective propulsor, and a DC electrical network electrically coupled to the first and second AC networks via respective first and second AC to DC converters, and to a further electrical motor, the further electrical motor being coupled to a propulsor.

Abstract: An aircraft propulsion system includes at least first and second electrical generators, each being configured to provide electrical power to a respective first and second AC electrical network. The system further comprises at least first and second AC electrical motors directly electrically coupled to a respective AC network and coupled to a respective propulsor, and a DC electrical network electrically coupled to the first and second AC networks via respective first and second AC to DC converters, and to a further electrical motor, the further electrical motor being coupled to a propulsor.

Abstract: An aircraft propulsion system (10) comprises at least first and second electrical generators (15a, 15b), each being configured to provide electrical power to a respective first and second AC electrical network (16a, 16b). The system (10) further comprises at least first and second AC electrical motors (19a, 19b) directly electrically coupled to a respective AC network (16a, 16b) and coupled to a respective propulsor (4), and a DC electrical network electrically coupled to the first and second AC networks (16a, 16b) via respective first and second AC to DC converters (17a, 17b), and to a further electrical motor 19c), the further electrical motor (19c) being coupled to a propulsor (4).

Abstract: Energy conversion apparatus comprising: an electrical machine including a rotor arranged to rotate about an axis, the rotor defining a first cavity therein; power electronic circuitry arranged at least partially around the axis and defining a second cavity therein, the power electronic circuitry being positioned adjacent to the electrical machine; a heat pipe positioned within the first cavity of the rotor and within the second cavity defined by the power electronic circuitry, the heat pipe being arranged to receive thermal energy from the rotor; and a cooling arrangement positioned at least partially within the second cavity and arranged to receive thermal energy from the power electronic circuitry and from the heat pipe.

Abstract: A power electronics module is provided having one or more power converter semiconductor components. The power electronics module further has a substrate having a first surface to which the one or more components are mounted, and having an opposing second surface from which project a plurality of heat transfer formations for enhancing heat transfer from the substrate. The power electronics module further has a coolant housing which sealingly connects to the substrate to form a void over the heat transfer formations of the second surface. The coolant housing has an inlet for directing a flow of an electrically insulating coolant into the void and an outlet for removing the coolant flow from the void, whereby heat generated during operation of the one or more components is transferred into the coolant flow via the substrate.

Abstract: An aircraft propulsion system (10) comprises at least first and second electrical generators (15a, 15b), each being configured to provide electrical power to a respective first and second AC electrical network (16a, 16b). The system (10) further comprises at least first and second AC electrical motors (19a, 19b) directly electrically coupled to a respective AC network (16a, 16b) and coupled to a respective propulsor (4), and a DC electrical network electrically coupled to the first and second AC networks (16a, 16b) via respective first and second AC to DC converters (17a, 17b), and to a further electrical motor 19c), the further electrical motor (19c) being coupled to a propulsor (4).

Abstract: A power electronics module is provided having one or more power converter semiconductor components. The power electronics module further has a substrate having a first surface to which the one or more components are mounted, and having an opposing second surface from which project a plurality of heat transfer formations for enhancing heat transfer from the substrate. The power electronics module further has a coolant housing which sealingly connects to the substrate to form a void over the heat transfer formations of the second surface. The coolant housing has an inlet for directing a flow of an electrically insulating coolant into the void and an outlet for removing the coolant flow from the void, whereby heat generated during operation of the one or more components is transferred into the coolant flow via the substrate.

Abstract: Energy conversion apparatus comprising: an electrical machine including a rotor arranged to rotate about an axis, the rotor defining a first cavity therein; power electronic circuitry arranged at least partially around the axis and defining a second cavity therein, the power electronic circuitry being positioned adjacent to the electrical machine; a heat pipe positioned within the first cavity of the rotor and within the second cavity defined by the power electronic circuitry, the heat pipe being arranged to receive thermal energy from the rotor; and a cooling arrangement positioned at least partially within the second cavity and arranged to receive thermal energy from the power electronic circuitry and from the heat pipe.