Abstract: An electric machine with a low profile retention assembly for retention of a stator core is disclosed. A first housing houses the stator core. The first housing has an axial end face with a circumferentially extending, shaped profile having recessed portions that project axially inward alternating with non-recessed portions. A portion of the stator core extends axially out from the recessed portions. A core retention spring is disposed circumferentially at the axial end face of the first housing. The core retention spring has direct contact with the portion of the stator core that extends axially out from the recessed portions of the first housing and the shaped profile of the housing. The core retention spring pushes against the portion of the stator core that extends that extends axially out from the first housing, imparting one or more of an axial load and radial load into the stator core.

Abstract: A propulsion assembly includes a first torque source coupled with a first shaft and a second torque source coupled with a second shaft. A coupler selectively couples the first and second torque sources. When the first and second torque sources are coupled via the coupler, in response to a command to decouple the first torque source, an unloading operation is performed to decrease the torque output provided by the first torque source to a threshold, and when reached, the first shaft is decoupled from the coupler. When the first torque source is coupled with the coupler but the second torque source is not, in response to a command to couple the second torque source, a speed matching operation is performed to increase the speed of the second shaft to match a speed of the first shaft, and when the speeds are matched, the second shaft is coupled to the coupler.

Abstract: An approach for facilitating mechanical and electrical connection of electric machines and electrical components in an electrical system using connectors with quick connect/disconnect electrical connectors is disclosed. Each quick connect/disconnect electrical connector can be placed on the end of an electrical power distribution cable that connects with an electric machine or electrical component. The electric machines and electrical components and the electrical power distribution cables can have hollow coolant passages formed therein to receive cooling fluid from a cooling device for direct cooling of the electric machines, electrical components and the electrical power distribution cables.

Abstract: A propulsion assembly includes a first torque source coupled with a first shaft and a second torque source coupled with a second shaft. A coupler selectively couples the first and second torque sources. When the first and second torque sources are coupled via the coupler, in response to a command to decouple the first torque source, an unloading operation is performed to decrease the torque output provided by the first torque source to a threshold, and when reached, the first shaft is decoupled from the coupler. When the first torque source is coupled with the coupler but the second torque source is not, in response to a command to couple the second torque source, a speed matching operation is performed to increase the speed of the second shaft to match a speed of the first shaft, and when the speeds are matched, the second shaft is coupled to the coupler.

Abstract: A power system including a power converter system and an electric machine is provided. In one aspect, the power converter system has first and second switching elements. The electric machine includes a first multiphase winding electrically coupled with the first switching elements and a second multiphase winding electrically coupled with the second switching elements. The first and second multiphase windings are arranged and configured to operate electrically opposite in phase with respect to one another. One or more processors control the first switching elements to generate first pulse width modulated (PWM) signals based on received voltage commands to render a first common mode signal and also control the second switching elements to generate second PWM signals based on received voltage commands to render a second common mode signal. The rendered first and second common mode signals have the same or similar waveform with opposite polarity with respect to one another.

Abstract: Aspects of the present disclosure are directed to systems and methods for detecting Partial Discharge (PD) associated with wide bandgap semiconductor-based electrical drive systems in real time. In one aspect, signals, including noise associated with drive switching and other background noises are detected using a sensing device. The signals are received by a real-time spectrum analyzer. The spectrum analyzer transforms the signals into the frequency domain and determines or registers the frequency domain profiles of the signals. The spectrum analyzer performs signal discrimination between at least one other signal included within the signals and switching noise based on their frequency domain profiles. Based on the discrimination analysis, the presence of a partial discharge signal may be detected. A physics-based signal discrimination approach can also be used for signal discrimination, for example utilizing pressure-dependency of characteristics of a PD signal.

Abstract: An electric machine can include a stator core having a plurality of core teeth that define a plurality of core slots in a surface thereof. A winding can be housed at least partially in the core slots. The winding can include a tube defining a channel through at least a portion thereof and one or more wires disposed along a surface of the tube that is opposite the channel. A cooling system can be operably coupled with the channel and configured to move a cooling fluid through the channel.

Abstract: A propulsor is provided including a gas turbine engine having a shaft and one or more bearings supporting the shaft, a rotor hub operatively coupled to the shaft and comprising a hub flange, an electric machine comprising a stator assembly and a rotor assembly, a rotor connection member operatively coupled to the rotor assembly of the electric machine and comprising a connection flange, and an insulated joint for operatively coupling the rotor assembly with the shaft. The insulated joint includes a plurality of insulative layers, at least one of the plurality of insulative layers extending between the hub flange and the connection flange to interrupt common mode electric current from flowing between the rotor assembly and the shaft.

Abstract: An electric component for an electric machine includes a body having slots defined therein, and a conductive winding extending out of axial end(s) of the slot(s). The electric component may include any electric machine component having conductive windings, e.g., a stator for a generator. The electric component includes a resin dam around the conductive winding at axial end(s) of the slot(s). The resin dam blocks liquid communication through at least a space between the conductive winding and an inner surface of the slot(s), during manufacture. The electric component also includes a (solidified) insulating resin in the slot(s) and against the resin dam(s) at the axial end(s) of the slot(s). Any number of the conductive windings and slots may include a resin dam, e.g., one, some or all. The resin dams ensure complete filling of the slots and encapsulation of the conductive windings.

Abstract: An electric machine having an electrically insulative manifold is disclosed. In one example aspect, an electric machine includes a non-electrically conductive manifold. The manifold defines a chamber operable to receive a cooling fluid. The electric machine includes a prime winding in fluid communication with the chamber and one or more secondary windings in electrical communication with the prime winding and in fluid communication with the chamber. Further, the electric machine includes an electric machine terminal extending through the non-electrically conductive manifold and coupled with the prime winding. The electric machine terminal can provide or collect cooling fluid from the chamber of the manifold and can act as the electrical connection point for directing electrical power to or from the windings of the electric machine.

Abstract: An electric winding assembly comprising a conductor core which includes at least a first end and a distal second end, an insulation layer overlying the conductor core, and a conductive shield layer overlying the insulation layer. The conductive shield layer further having a terminal end conductively connected with the conductive shield layer.

Abstract: A power system including a power converter system and an electric machine is provided. In one aspect, the power converter system has first and second switching elements. The electric machine includes a first multiphase winding electrically coupled with the first switching elements and a second multiphase winding electrically coupled with the second switching elements. The first and second multiphase windings are arranged and configured to operate electrically opposite in phase with respect to one another. One or more processors control the first switching elements to generate first pulse width modulated (PWM) signals based on received voltage commands to render a first common mode signal and also control the second switching elements to generate second PWM signals based on received voltage commands to render a second common mode signal. The rendered first and second common mode signals have the same or similar waveform with opposite polarity with respect to one another.

Abstract: A hybrid-electric propulsion system is provided. In one example aspect, the hybrid-electric propulsion system includes a power converter and a propulsor. The propulsor includes a gas turbine engine having a shaft and one or more bearings supporting the shaft. The propulsor also includes an electric machine electrically coupled with the power converter. The electric machine includes a stator assembly and a rotor assembly. The rotor assembly has a rotor and a rotor connection assembly. The rotor connection assembly operatively couples the rotor with the shaft. The rotor connection assembly has an insulated joint for interrupting common mode electric current from flowing from the rotor of the electric machine to the shaft. A grounding device is included to electrically ground the shaft. The power converter includes an electromagnetic interference filter to reduce common mode voltage reaching the electric machine.

Abstract: A power system including a power converter system and an electric machine is provided. In one aspect, the power converter system has first and second switching elements. The electric machine includes a first multiphase winding electrically coupled with the first switching elements and a second multiphase winding electrically coupled with the second switching elements. The first and second multiphase windings are arranged and configured to operate electrically opposite in phase with respect to one another. One or more processors control the first switching elements to generate first pulse width modulated (PWM) signals based on received voltage commands to render a first common mode signal and also control the second switching elements to generate second PWM signals based on received voltage commands to render a second common mode signal. The rendered first and second common mode signals have the same or similar waveform with opposite polarity with respect to one another.

Abstract: An electric machine having a hybrid insulative-conductive manifold is disclosed. In one aspect, an electric machine includes a manifold that includes an insulative plate and a conductive backplate positioned adjacent to the insulative plate. The insulative plate and the backplate define a first channel and a second channel therebetween. The electric machine also includes a prime winding and a secondary winding electrically isolated from the prime winding. The prime winding and the secondary winding are both in fluid communication with the first channel and the second channel. A terminal conductor extends through the backplate and insulative plate and is electrically coupled with the prime winding. The terminal conductor is electrically isolated from the backplate and provides cooling fluid to the prime winding and the first channel so that cooling fluid flows between the terminal conductor and the prime winding and between the terminal conductor and the first channel.

Abstract: A hybrid-electric propulsion system is provided. In one example aspect, the hybrid-electric propulsion system includes a power converter and a propulsor. The propulsor includes a gas turbine engine having a shaft and one or more bearings supporting the shaft. The propulsor also includes an electric machine electrically coupled with the power converter. The electric machine includes a stator assembly and a rotor assembly. The rotor assembly has a rotor and a rotor connection assembly. The rotor connection assembly operatively couples the rotor with the shaft. The rotor connection assembly has an insulated joint for interrupting common mode electric current from flowing from the rotor of the electric machine to the shaft. A grounding device is included to electrically ground the shaft. The power converter includes an electromagnetic interference filter to reduce common mode voltage reaching the electric machine.

Abstract: An electric machine having an electrically insulative manifold is disclosed. In one example aspect, an electric machine includes a non-electrically conductive manifold. The manifold defines a chamber operable to receive a cooling fluid. The electric machine includes a prime winding in fluid communication with the chamber and one or more secondary windings in electrical communication with the prime winding and in fluid communication with the chamber. Further, the electric machine includes an electric machine terminal extending through the non-electrically conductive manifold and coupled with the prime winding. The electric machine terminal can provide or collect cooling fluid from the chamber of the manifold and can act as the electrical connection point for directing electrical power to or from the windings of the electric machine.

Abstract: An electric machine can include a stator core having a plurality of core teeth that define a plurality of core slots in a surface thereof. A winding can be housed at least partially in the core slots. The winding can include a tube defining a channel through at least a portion thereof and one or more wires disposed along a surface of the tube that is opposite the channel. A cooling system can be operably coupled with the channel and configured to move a cooling fluid through the channel.

Abstract: Aspects of the present disclosure are directed to systems and methods for detecting Partial Discharge (PD) associated with wide bandgap semiconductor-based electrical drive systems in real time. In one aspect, signals, including noise associated with drive switching and other background noises are detected using a sensing device. The signals are received by a real-time spectrum analyzer. The spectrum analyzer transforms the signals into the frequency domain and determines or registers the frequency domain profiles of the signals. The spectrum analyzer performs signal discrimination between at least one other signal included within the signals and switching noise based on their frequency domain profiles. Based on the discrimination analysis, the presence of a partial discharge signal may be detected. A physics-based signal discrimination approach can also be used for signal discrimination, for example utilizing pressure-dependency of characteristics of a PD signal.

Abstract: An electric winding assembly comprising a conductor core which includes at least a first end and a distal second end, an insulation layer overlying the conductor core, and a conductive shield layer overlying the insulation layer. The conductive shield layer further having a terminal end conductively connected with the conductive shield layer.