Abstract: Described is a method including monitoring a point of regulation voltage input to a generator control unit and monitoring a generator output voltage as a backup point of regulation voltage input. The method also includes detecting an overvoltage fault at the point of regulation voltage input, the backup point of regulation voltage input, or both. Additionally, the method includes opening a first solid-state switch (110) in response to detecting the overvoltage fault. Opening the first solid-state switch (110) prevents provision of an input signal (104) to a generator excitation field (102). Further, the method includes opening a generator excitation field relay (112) in response to detecting the overvoltage fault. Opening the excitation field relay (112) also prevents provision of the input signal (104) to the generator excitation field (102).

Abstract: Systems and techniques for engine starter control may include determining a current speed band associated with an engine start for a current time increment, determining a previous speed band associated with the engine start for a previous time increment within the engine start, receiving a measured current value, determining a target current value based on the current speed band, the previous speed band, whether an acceleration or deceleration occurred between the current speed band and the previous speed band, and a mode of a system for engine starter control, and adjusting a current for the engine start based on the target current value.

Abstract: According to one aspect, a starter-generator control unit may include a comparator, a pulse width modulation (PWM) duty cycle generator, a randomizer, and a sequencer. The comparator may receive a current reading from a current sensor and a target current from a target current lookup table and generate an output comparator signal indicative of an increase or a decrease in a current value of a pulse width modulation (PWM) duty cycle. The PWM duty cycle generator may receive the signal from the comparator and generate an output PWM signal. The randomizer may generate a randomly time-varying update signal. The PWM duty cycle generator may receive the randomly time-varying update signal which may control a cycle time associated with the PWM duty cycle generator. The sequencer may receive the output PWM signal and generate a gate control signal for controlling an inverter based on the output PWM signal.

Abstract: A variable frequency generator (VFG) may include a housing, a shaft, a rotor, and a stator with slots. The VFG also includes a first set of stator windings including a first subset of windings and a second subset of windings and a second set of stator windings including a first subset of windings and a second subset of windings. The windings of the first subset of the first set of stator windings are co-located with the windings of the first subset of the second set of stator windings so as to share a common slot of the plurality of slots of the stator. Further, the windings of the second subset of the first set of stator windings are co-located with the windings of the second subset of the second set of stator windings so as to share a common alternative slot of the plurality of slots of the stator.

Abstract: Systems and techniques for engine starter control may include determining a current speed band associated with an engine start for a current time increment, determining a previous speed band associated with the engine start for a previous time increment within the engine start, receiving a measured current value, determining a target current value based on the current speed band, the previous speed band, whether an acceleration or deceleration occurred between the current speed band and the previous speed band, and a mode of a system for engine starter control, and adjusting a current for the engine start based on the target current value.

Abstract: A system and method for snubbing transformer leakage energy in a power supply having a transformer and a main switch, in which leakage energy is stored in a capacitor as stored leakage energy when the main switch is turned off, and the stored leakage energy is transferred to the transformer through an inductor when the main switch is turned on.

Abstract: A system and method for snubbing transformer leakage energy in a power supply having a transformer and a main switch, in which leakage energy is stored in a capacitor as stored leakage energy when the main switch is turned off, and the stored leakage energy is transferred to the transformer through an inductor when the main switch is turned on.

Abstract: Described is a hybrid permanent magnet and wire wound starter generator system. The system includes a polyphase stator that converts a rotating magnetic field to electrical energy. The system also includes a rotor including a plurality of permanent magnets and a wound rotor section. The plurality of permanent magnets and the wound rotor section each generate a portion of the rotating magnetic field. Further, the system includes a controller that controls a polarity of the wound rotor section by transitioning the wound rotor section between a magnetic flux enhancement mode and a magnetic flux weakening mode.

Abstract: Described is a system that includes a polyphase generator and a polyphase bridge rectifier electrically coupled to an output of the polyphase generator. The polyphase bridge rectifier may output a positive rectified ripple signal and a negative rectified ripple signal, and the positive rectified ripple signal and the negative rectified ripple signal may be summed to produce a total ripple signal. Further, the system may include a generator regulation feedback control loop that regulates the output of the polyphase generator with a field control signal. In an embodiment, the field control signal is based on summing the total ripple signal and a reference voltage.

Abstract: Described is a method that includes receiving a reference signal including an adjustable-amplitude sine wave. The method also includes receiving a voltage feedback signal from a voltage control loop. The voltage feedback signal is a point-of-regulation sine wave, and the voltage control loop includes a first response time. The method also includes comparing the reference signal to the voltage feedback signal to generate an error value. Further, the point-of-regulation sine wave is controlled in the method based on a proportional-integral-derivative input and a current feedback signal. The proportional-integral-derivative input is based on the error value. Additionally, the method includes adjusting the reference signal based on an output of an amplitude control loop. The amplitude control loop includes a second response time that is at least one order of magnitude slower than the first response time of the voltage control loop.

Abstract: Described is a system that includes a polyphase generator and a polyphase bridge rectifier electrically coupled to an output of the polyphase generator. The polyphase bridge rectifier may output a positive rectified ripple signal and a negative rectified ripple signal, and the positive rectified ripple signal and the negative rectified ripple signal may be summed to produce a total ripple signal. Further, the system may include a generator regulation feedback control loop that regulates the output of the polyphase generator with a field control signal. In an embodiment, the field control signal is based on summing the total ripple signal and a reference voltage.

Abstract: Described is a method that includes receiving a reference signal including an adjustable-amplitude sine wave. The method also includes receiving a voltage feedback signal from a voltage control loop. The voltage feedback signal is a point-of-regulation sine wave, and the voltage control loop includes a first response time. The method also includes comparing the reference signal to the voltage feedback signal to generate an error value. Further, the point-of-regulation sine wave is controlled in the method based on a proportional-integral-derivative input and a current feedback signal. The proportional-integral-derivative input is based on the error value. Additionally, the method includes adjusting the reference signal based on an output of an amplitude control loop. The amplitude control loop includes a second response time that is at least one order of magnitude slower than the first response time of the voltage control loop.

Abstract: Described is a hybrid permanent magnet and wire wound starter generator system. The system includes a polyphase stator that converts a rotating magnetic field to electrical energy. The system also includes a rotor including a plurality of permanent magnets and a wound rotor section. The plurality of permanent magnets and the wound rotor section each generate a portion of the rotating magnetic field. Further, the system includes a controller that controls a polarity of the wound rotor section by transitioning the wound rotor section between a magnetic flux enhancement mode and a magnetic flux weakening mode.

Abstract: Described is a method including monitoring a point of regulation voltage input to a generator control unit and monitoring a generator output voltage as a backup point of regulation voltage input. The method also includes detecting an overvoltage fault at the point of regulation voltage input, the backup point of regulation voltage input, or both. Additionally, the method includes opening a first solid-state switch (110) in response to detecting the overvoltage fault. Opening the first solid-state switch (110) prevents provision of an input signal (104) to a generator excitation field (102). Further, the method includes opening a generator excitation field relay (112) in response to detecting the overvoltage fault. Opening the excitation field relay (112) also prevents provision of the input signal (104) to the generator excitation field (102).

Abstract: Methods and apparatus provide for commutating windings of a polyphase machine such that electromagnetic fields of stator and rotor phases of the polyphase machine produce at least one of motoring and generating torque, wherein the controller is operable to automatically vary at least one of a lead angle measured between the electromagnetic fields of the stator and rotor phases and rotor excitation parameters as a function of a rotational speed of the polyphase machine.

Abstract: Methods and apparatus provide for: commutating windings of a polyphase machine such that electromagnetic fields of stator and rotor phases of the polyphase machine produce at least one of motoring and generating torque; providing a first rotor excitation voltage having substantially no DC component when a rotational speed of the polyphase machine is below a predetermined value; and providing a second rotor excitation voltage having a DC component when the rotational speed of the polyphase machine is above the predetermined value.

Abstract: An inductive debris monitor for detecting chip-particles in tubing of a fluid wetted system. The inductive debris monitor includes a multi-turn detector and an electronic circuit having a resistor bridge configuration. The multi-turn probe detector wraps around the tubing of a fluid wetted system a plurality of times to detect the presence of the chip-particles while the electronic circuit analyzes and deciphers the detected chip-particle information.