Abstract: In some examples, an electrical power system includes a solid state power converter including a first set of switches on a source side of the solid state power converter and a second set of switches on a load side of the solid state power converter. The electrical power system also includes a power source connected to the source side of the solid state power converter and also includes a differential bus connected to the load side of the solid state power converter. The electrical power system further includes a controller configured to receive a first signal indicating a current at the source side and receive a second signal indicating a current at the load side. The controller is further configured to detect, based on a time derivative of the first signal and a time derivative of the second signal, a fault in the electrical power system.

Abstract: A voltage controlled aircraft electric propulsion system includes an electric propulsion system. The voltage controlled aircraft electric propulsion system may include electric propulsors providing thrust for the aircraft. In hybrid systems, a gas turbine engine may also be included. The electric propulsion system may include at least one electric generator power source, at least one propulsor motor load, and at least one stored energy power source, such as a battery. The propulsor motor load may be supplied power from a power supply bus. The voltage of the power supply bus may be adjusted according to an altitude of the aircraft while maintaining a substantially constant current flow to the propulsor motor load. Due to the adjustment to lower voltages at increased altitude, insulations levels may be lower.

Abstract: In examples of the disclosure, a device may be couple an electrical load to a power source. The device may have a first coupling configured to couple to the power source and a second coupling configured to couple to the electrical load. The device may have a plurality of strands electrically disposed between the first coupling and the second coupling. Each of the plurality of strands may have a coating having a resistivity greater than 1.8×10?8 ?-m and less than 1 ?-m and a center conductor wrapped, at least in part, by the coating.

Abstract: A system includes a first generator configured to output a first plurality of AC signals; a second generator configured to output a second plurality of AC signals; a first set of rectifiers configured to convert the first plurality of AC signals into a first plurality of DC signals for output onto a first DC bus, wherein each of the first set of rectifiers includes a respective contactor configured to de-couple a DC output of the respective rectifier from the first DC electrical bus; and a second set of rectifiers configured to convert the second plurality of AC signals into a second plurality of DC signals for output onto a second DC bus, wherein each of the second set of rectifiers includes a respective contactor configured to de-couple a DC output of the respective rectifier from the second DC bus.

Abstract: A system for providing propulsive electrical power for an aircraft, the system comprising: a first generator configured to output a first plurality of AC electrical signals; a second generator configured to output a second plurality of AC electrical signals; a first set of rectifiers configured to convert the first plurality of AC electrical signals into a first plurality of DC electrical signals for output onto a first DC electrical bus of a plurality of DC electrical busses; and a second set of rectifiers configured to convert the second plurality of AC electrical signals into a second plurality of DC electrical signals for output onto a second DC electrical bus of the plurality of DC electrical busses, wherein each rectifier of the plurality of rectifiers includes a respective controller of a plurality of controllers, and wherein the plurality of controllers are configured to coordinate response to detected faults.

Abstract: A system includes a first generator configured to output a first plurality of AC signals; a second generator configured to output a second plurality of AC signals; a first set of rectifiers configured to convert the first plurality of AC signals into a first plurality of DC signals for output onto a first DC bus, wherein each of the first set of rectifiers includes a respective contactor configured to de-couple a DC output of the respective rectifier from the first DC electrical bus; and a second set of rectifiers configured to convert the second plurality of AC signals into a second plurality of DC signals for output onto a second DC bus, wherein each of the second set of rectifiers includes a respective contactor configured to de-couple a DC output of the respective rectifier from the second DC bus.

Abstract: A turbo-generator system for generating propulsive electrical power for an aircraft includes an electric machine comprising: a rotor configured to be rotated by a gas-turbine of the turbo-generator system; a stator comprising: a first active section comprising first windings surrounding a first portion of the rotor; and a second active section comprising second windings surrounding a second portion of the rotor.

Abstract: A fault monitoring device may monitor and detect for faults corresponding to a high-side voltage rail, to low-side voltage rail, or internally within a voltage source connected to the high-side voltage rail and the low-side voltage rail. The fault monitoring device may determine sample voltage levels and/or sample resistance values to detect the faults. Also, in various embodiments, the fault monitoring device may perform one or more fault monitoring processes over multiple stages. The fault monitoring device may determine the sample voltage levels and/or the sample resistance values while switching a secondary resistance circuit in different states over the multiple stages.

Abstract: A fault monitoring device may monitor and detect for faults corresponding to a high-side voltage rail, to low-side voltage rail, or internally within a voltage source connected to the high-side voltage rail and the low-side voltage rail. The fault monitoring device may determine sample voltage levels and/or sample resistance values to detect the faults. Also, in various embodiments, the fault monitoring device may perform one or more fault monitoring processes over multiple stages. The fault monitoring device may determine the sample voltage levels and/or the sample resistance values while switching a secondary resistance circuit in different states over the multiple stages.

Abstract: In some examples, this disclosure describes a method for detecting a fault in an electrical power system comprising a bus connected between a first solid state power converter and a second solid state power converter. The method includes receiving, at a controller of the electrical power system, a first signal indicating a current at a source side of the first solid state power converter, wherein the source side of the first solid state power converter is connected to a power source of the electrical power system. The method also includes receiving, at the controller, a second signal indicating a current at the bus and determining, by the controller, that a fault occurred in the electrical power system based on the first signal and further based on the second signal. The method further includes controlling the first solid state power converter in response to determining that the fault occurred.

Abstract: A rotor assembly includes a rotor core having an axial length and configured to rotate about a longitudinal axis and at least one permanent magnet disposed about a radially outer surface of the rotor core. The rotor assembly further includes an electrical insulator disposed between the radially outer surface of the rotor core and the at least one permanent magnet and configured to disrupt an electrical conduction path along the axial length of the rotor core.

Abstract: A fault monitoring device may monitor and detect for faults corresponding to a high-side voltage rail, to low-side voltage rail, or internally within a voltage source connected to the high-side voltage rail and the low-side voltage rail. The fault monitoring device may determine sample voltage levels and/or sample resistance values to detect the faults. Also, in various embodiments, the fault monitoring device may perform one or more fault monitoring processes over multiple stages. The fault monitoring device may determine the sample voltage levels and/or the sample resistance values while switching a secondary resistance circuit in different states over the multiple stages.

Abstract: A fault monitoring device may monitor and detect for faults corresponding to a high-side voltage rail, to low-side voltage rail, or internally within a voltage source connected to the high-side voltage rail and the low-side voltage rail. The fault monitoring device may determine sample voltage levels and/or sample resistance values to detect the faults. Also, in various embodiments, the fault monitoring device may perform one or more fault monitoring processes over multiple stages. The fault monitoring device may determine the sample voltage levels and/or the sample resistance values while switching a secondary resistance circuit in different states over the multiple stages.

Abstract: An example method includes receiving, by one or more processors and via a sensor, a signal representing operational characteristics of a device included in an aircraft; determining, by the one or more processors and based on the signal, a partial discharge intensity value; receiving, by the one or more processors and via an environmental sensor, at least one environmental measurement of the device; modifying, by the one or more processors and based on the at least one environmental measurement, the partial discharge intensity value to determine a modified partial discharge intensity value; and responsive to determining that the modified partial discharge intensity value satisfies a threshold, outputting an alert signal for the device.

Abstract: A voltage controlled aircraft electric propulsion system includes an electric propulsion system. The voltage controlled aircraft electric propulsion system may include electric propulsors providing thrust for the aircraft. In hybrid systems, a gas turbine engine may also be included. The electric propulsion system may include at least one electric generator power source, at least one propulsor motor load, and at least one stored energy power source, such as a battery. The propulsor motor load may be supplied power from a power supply bus. The voltage of the power supply bus may be adjusted according to an altitude of the aircraft while maintaining a substantially constant current flow to the propulsor motor load. Due to the adjustment to lower voltages at increased altitude, insulations levels may be lower.

Abstract: A bi-directional direct current (DC) solid state power controller (SSPC) architecture and control method. The SSPC protects a DC distribution system by isolating both the positive and negative buses independently in case of short circuit or ground fault. The SSPC architecture includes two self-heal interleaved capacitors and includes a fast, soft-charging control technique that provides line-isolated charging of the DC bulk capacitor to avoid inrush current when powering up the DC distribution system. The soft-charging function alternately charges one of the two interleaved capacitors, while the other capacitor discharges to the DC bulk capacitor. Repetitive switching results in a charging and discharging process that increases the voltage of the DC bulk capacitor prior to powering up the DC distribution system, while keeping the DC power source isolated from the load.

Abstract: A bi-directional direct current (DC) solid state power controller (SSPC) architecture and control method. The SSPC protects a DC distribution system by isolating both the positive and negative buses independently in case of short circuit or ground fault. The SSPC architecture includes two self-heal interleaved capacitors and includes a fast, soft-charging control technique that provides line-isolated charging of the DC bulk capacitor to avoid inrush current when powering up the DC distribution system. The soft-charging function alternately charges one of the two interleaved capacitors, while the other capacitor discharges to the DC bulk capacitor. Repetitive switching results in a charging and discharging process that increases the voltage of the DC bulk capacitor prior to powering up the DC distribution system, while keeping the DC power source isolated from the load.

Abstract: In some examples, this disclosure describes a method for detecting a fault in an electrical power system comprising a bus connected between a first solid state power converter and a second solid state power converter. The method includes receiving, at a controller of the electrical power system, a first signal indicating a current at a source side of the first solid state power converter, wherein the source side of the first solid state power converter is connected to a power source of the electrical power system. The method also includes receiving, at the controller, a second signal indicating a current at the bus and determining, by the controller, that a fault occurred in the electrical power system based on the first signal and further based on the second signal. The method further includes controlling the first solid state power converter in response to determining that the fault occurred.

Abstract: In some examples, an electrical power system includes a solid state power converter including a first set of switches on a source side of the solid state power converter and a second set of switches on a load side of the solid state power converter. The electrical power system also includes a power source connected to the source side of the solid state power converter and also includes a differential bus connected to the load side of the solid state power converter. The electrical power system further includes a controller configured to receive a first signal indicating a current at the source side and receive a second signal indicating a current at the load side. The controller is further configured to detect, based on a time derivative of the first signal and a time derivative of the second signal, a fault in the electrical power system.

Abstract: A control unit of an electrical system is described. The control unit causes some of the switches in a power converter of the electrical system to not be shut down and not conducting upon detection of a fault current caused by a line-to-line fault. Instead, the control unit causes at least one of the switches to be switched-on and conducting to allow the some of the fault current to flow through the at least one switch, before activating a protection device that creates an open circuit and breaks the fault.