An auxiliary power unit (APU) control system for an aircraft is disclosed. The APU control system includes an APU, one or more processors, and a memory coupled to the one or more processors. The memory stores data comprising a database and program code that, when executed by the one or more processors, causes the APU control system to receive a one or more ambient signals indicative of an air density value and one or more power signals indicative of a specific amount of power generated by the APU. The APU control system is further caused to determine a variable rotational speed of the APU based on the air density value and instruct the APU to operate at the variable rotational speed. The APU continues to generate the specific amount of power when operating at the variable rotational speed.

An auxiliary power unit (APU) control system for an aircraft is disclosed, and includes an APU drivingly coupled to one or more generators, one or more processors, and a memory coupled to the one or more processors. The memory stores data comprising a database and program code that, when executed by the one or more processors, causes the APU control system to receive one or more ambient signals indicative of an air density value and one or more power signals indicative of a specific amount of power generated by the APU. The system is further caused to determine a first variable rotational speed of the APU based on the air density value. The APU continues to generate the specific amount of power when operating at the first variable rotational speed. After instructing the APU to operate at the first variable rotational speed, the system receives an electrical load signal.

Actuators are components of machines, which move and/or control a mechanism or system. During operation, actuators can experience regeneration events, with the actuator actually generating excess energy (e.g., regenerative energy) which must be stored or dissipated to avoid damaging the power supply. An actuator motor controller is configured to implement field oriented voltage control and flux weakening voltage control without current sensors. Dissipating regenerative energy includes providing a motor controller to command a motor drive to modify an input voltage, or to dissipate regenerative energy in a dump circuit. This command can cause motor windings to dissipate regenerative energy. Systems having a plurality of actuators distribute regenerative energy from one actuator to another. A central controller provides centralized regeneration dissipation control for the plurality of actuators. A power distribution unit includes a dump resistor to dissipate regenerative energy in addition to or instead of in the actuators.

A system can include a first generator configured to operate in a first speed range to produce a predetermined output characteristic, a second generator configured to operate at a second speed range different from the first speed range to produce the predetermined output characteristic, and a controller configured to activate the first generator at and/or above a first low activation speed and at and/or below a first high activation speed within the first speed range. The controller can be configured to activate the second generator at and/or above a second low activation speed within the second speed range. The controller can be configured to deactivate the first generator at and/or above a first high deactivation speed. The controller can be configured to deactivate the second generator at and/or below a second low deactivation speed.

A variable wobbler plate has a stub shaft and a pivot shaft. The pivot shaft has a smaller diameter portion and a larger diameter portion. The smaller diameter portion has a generally cylindrical outer periphery with a flat over a limited circumferential extent and a diameter to opposed portions of the generally cylindrical portion defining a first distance. A second distance is defined from an end of the smaller diameter portion spaced furthest from the stub shaft to an end of the larger diameter portion spaced closest to the stub shaft and measured along a central axis of the pivot shaft and defines a second distance. A ratio of the first distance to the second distance is between 0.60 and 0.75. An integrated drive generator and a method are also disclosed.

A power generation system includes an electric generator mechanically driven by a variable speed kinetic source, a first power conversion system connected with an output of the electric generator, and a second power conversion system connected with the output of the electric generator, wherein the electric generator and power conversion systems are adapted to convert the output of the electric generator to a predetermined direct current (DC) voltage.

An aerial vehicle and system for automatically detecting an object (e.g., human, pet, or other animal) approaching the aerial vehicle is described. When an approaching object is detected by an object detection component, a safety profile may be executed to reduce or avoid any potential harm to the object and/or the aerial vehicle. For example, if the object is detected entering a safety perimeter of the aerial vehicle, the rotation of a propeller closest to the object may be stopped to avoid harming the object and rotations of remaining propellers may be modified to maintain control and flight of the aerial vehicle.

There is described a method for and system for starting at least one engine from a twin engine installation. The starting system comprises a first engine arrangement comprising a first electric machine having a single rotor dual stator configuration, a first dual channel power control unit coupled to the first electric machine, and a first dual channel full authority digital engine control (FADEC) coupled to the first dual channel power control unit; a second engine arrangement comprising a second electric machine having a single rotor dual stator configuration, a second dual channel power control unit coupled to the second electric machine, and a second dual channel full authority digital engine control (FADEC) coupled to the second dual channel power control unit; an energy storage unit coupled to the first engine arrangement and the second engine arrangement and having at least a first super-capacitor and a second super-capacitor; and a DC to DC converter configured to receive a first voltage level from a power source, increase the first voltage level to a second voltage level, and charge the first super-capacitor and the second super-capacitor to the second voltage level.

An electrical machine includes a first set of windings, a second set of windings and a power controller connected to the first set of windings by a first set of feeder cables. The power controller controls the current and/or voltage supplied to the first set of windings at a control frequency and generates a test signal to supply to the first set of windings. The test signal has one or more frequency components having a frequency that is significantly higher than the control frequency. The test signal in the first set of windings generates an electromagnetic field that induces a current or voltage in the second set of windings. The power controller includes a detector connected to the second set of windings by a second set of feeder cables. The detector measures the voltage and/or current response of the induced current or voltage.

An aircraft power generation unit to generate direct current (DC) power provided to a load includes a six-phase permanent magnet generator (PMG) and a rectifier section that converts alternating current (AC) voltage produced by the six-phase PMG into a DC output. The rectifier section includes a first six-pulse rectifier and a second six-pulse rectifier connected to the second set of windings. The unit also includes an output bus configured to be connected to the load and including a positive rail and a negative rail connected to the second rectifier and an output voltage regulation section that provides an output voltage to the output bus. The unit also include a controller that provides a pulse width modulated (PWM) signal to the output voltage regulation section to vary the output voltage provided to the output bus.