A method of controlling a variable speed constant frequency (VSCF) power converter is provided. The method includes receiving a determination that a sensed AC current output has exceeded a predetermined limit. The AC current output is converted from a DC voltage and has a constant frequency. The DC voltage is converted from a variable frequency AC voltage. The variable frequency AC voltage is generated in response to a mechanical energy input having a varying parameter. The method further includes decreasing the DC voltage in response to a determination that the sensed AC current output has exceeded the predetermined limit.

Control logic for a power sharing system on a hybrid propulsion aircraft, utilizing parallel multiple control loops outputting difference commands which provide bumpless transfer between control loops without integrator wind up or reset logic, allowing for efficient load distribution between electric generators and batteries powering electric motors.

A distributed propulsion system includes a first propulsor and a second propulsor, a first generator configured to generate a first AC current, and a second generator configured to generate a second AC current. The system includes a power regulation circuit. The power regulation circuit includes a first current path that includes a first power electronics circuit, a second current path that includes a second power electronics circuit, a third current path that bypasses the first and second power electronics circuits, and a fourth current path that bypasses the first and second power electronics circuits. The power regulation circuit also includes a plurality of switches configured to selectively couple each respective input to a respective selected output to cause a respective current to flow from the respective input to the respective selected output via one of the first current path, second current path, third current path, or fourth current path.

An electrical power unit is disclosed. The electrical power unit includes a controller configured to generate a first control signal based on a first operational state of an engine, a multiphase electrical machine including a plurality of three-phase windings; and an electrical power conditioning subunit operatively coupled to the controller, where the electrical power conditioning subunit comprises a plurality of converters, where at least one converter is electrically coupled to a corresponding three-phase winding of the plurality of three-phase windings based on the first control signal, and where the electrical power conditioning subunit is configured to transmit a first electrical power from the at least one converter to the corresponding three-phase winding, where the multiphase electrical machine is configured to generate a mechanical power based on the first electrical power and rotate a crankshaft operatively coupled to the engine based on the generated mechanical power to start the engine.

A motor actuating apparatus includes three phase connections for three motor phase connections, a high-connection for a supply voltage and a low-connection for a reference potential of the supply voltage, three bridge branches having a series connection of a high-switch and a low-switch and a control device for actuating the switches of the bridge branches. The high-switches are connected to the high-connection and the low-switches are connected to the low-connection. Each of the three phase connections is connected to exactly one of the three bridge branches between the high-switch and the low-switch. The control device is adapted for actuating the switches of the bridge branches such that during a first time period a first phase connection is switched to passive and the second phase connection and third phase connection are alternatingly connected to the high-connection and the low-connection in a predeterminable duty cycle if the supply voltage is applied.

A method of controlling a permanent magnet synchronous electric machine (PMSM) drive using a Deadbeat Predictive Current Control (DBPCC) scheme is provided. The method comprises: determining d-axis and q-axis stator current values (i.sub.d, i.sub.q) representative of a measured PMSM current; determining d-axis and q-axis reference current values (i.sub.d*, i.sub.q*); based on the stator current values (i.sub.d, i.sub.q) and the reference current values (i.sub.d*, i.sub.q*), determining d-axis and q-axis current correction values (C.sub.d, C.sub.q); determining corrected reference current values (i.sub.d**, i.sub.q**) as a sum of the reference current values (i.sub.d*, i.sub.q*) and the current correction values (C.sub.d, C.sub.q); and controlling the PMSM drive using the corrected reference current values (i.sub.d**, i.sub.q**) as reference current inputs of the DBPCC scheme. A controller for performing the method; a system comprising the controller, a PMSM and associated power electronics; and a computer program for performing the method are also provided.

There is provided a hybrid electric aircraft propulsion system and method for operating same. The method comprises providing, to a first electric motor and a second electric motor, alternating current (AC) electric power from a generator, the generator receiving rotational power from a thermal engine, providing, to the first electric motor and the second electric motor, AC electric power from at least one motor inverter, the at least one motor inverter configured to convert DC electric power from a DC power source into AC electric power, and selectively driving the first and second electric motors from the generator, the at least one motor inverter, or a combination thereof, wherein the first electric motor drives a first rotating propulsor and the second electric motor drives a second rotating propulsor.

An aircraft comprising a hybrid electric aircraft propulsion system. The system comprises a first sub-assembly having a first electric propulsor assembly and a first thermal propulsor assembly, the first thermal propulsor assembly having a first thermal engine, a first generator and a first rotating propulsor, the first electric propulsor assembly attached to the aircraft at a first location and the first thermal propulsor assembly attached to the aircraft at a second location. The system also comprises a second sub-assembly having a second electric propulsor assembly and a second thermal propulsor assembly, the second thermal propulsor assembly having a second thermal engine, a second generator and a second rotating propulsor, the second electric propulsor assembly attached to the aircraft at a third location and the second thermal propulsor assembly attached to the aircraft at a fourth location.

Methods and systems for operating a hybrid electric aircraft propulsion system mounted to an aircraft. The method comprises driving a first rotating propulsor from a first electric motor operatively connected to a generator, driving a second rotating propulsor from a second electric motor operatively connected to the generator, and driving a third rotating propulsor from a thermal engine, the thermal engine operatively connected to the generator and configured to drive the generator.

Methods and systems for operating a hybrid electric aircraft propulsion system. The method comprises providing alternating current (AC) electric power to a first electric motor to drive a first rotating propulsor, providing the first electric motor with AC electric power from at least one motor inverter operatively coupled to a direct current (DC) power source, detecting a failure in a path to the first electric motor, and selectively rearranging a first switching arrangement between the generator, the at least one motor inverter, and the first electric motor.