Abstract: Systems and methods for testing a lightning protection circuit are provided. Aspects include providing an alternating current (AC) test signal source coupled to a circuit under test, the circuit under test comprising a lightning protection circuit having a threshold voltage, a first filter, and a second filter, providing a direct current (DC) voltage supply in series with a filtering device, the filtering device coupled to the AC test signal source, providing a first capacitor coupled between the AC test signal source and the circuit under test, operating the DC voltage supply and the AC test signal source to provide a first test signal to the circuit under test, wherein the first test signal comprise a first voltage that exceeds the threshold voltage, measuring a first impedance of the circuit under test responsive to providing the first test signal, wherein the first impedance corresponds to the first filter.

Abstract: A method and system for monitoring a change in leakage current through a transient voltage suppressor, TVS, device, the method comprising locating a tunnel magneto-resistance, TMR, device in proximity to the TVS device and measuring the change in resistance of the TMR device.

Abstract: Systems and methods for testing a lightning protection circuit are provided. Aspects include providing an alternating current (AC) test signal source coupled to a circuit under test, the circuit under test comprising a lightning protection circuit having a threshold voltage, a first filter, and a second filter, providing a direct current (DC) voltage supply in series with a filtering device, the filtering device coupled to the AC test signal source, providing a first capacitor coupled between the AC test signal source and the circuit under test, operating the DC voltage supply and the AC test signal source to provide a first test signal to the circuit under test, wherein the first test signal comprise a first voltage that exceeds the threshold voltage, measuring a first impedance of the circuit under test responsive to providing the first test signal, wherein the first impedance corresponds to the first filter.

Abstract: A power system includes an inverter that convert a DC voltage to a three-phase alternating current (AC) voltage. One or more switch drivers generate a pulse width modulation (PWM) drive signal that drives the inverter. The power system further includes a controller that determines a modulation index associated with the PWM drive signal and injects a harmonic into the PWM drive signal in response to the modulation index exceeding a modulation index threshold value.

Abstract: A pulse width modulator (PWM) of a multi-phase power converter is provided. The PWM includes a signal modulator that corresponds to each phase of the converter. Each signal modulator of the PWM is configured to receive a unique triangle carrier signal, receive a unique sine wave signal, compare the received triangle carrier signal and the received sine wave signal, and output at least one control signal based on a result of the comparison. The control signal controls an inverter that applies pulse width modulation to a DC power for converting the DC power to a multi-phase power, AC harmonics of the multi-phase power filtered by a common mode inductor.

Abstract: A power system includes an inverter that convert a DC voltage to a three-phase alternating current (AC) voltage. One or more switch drivers generate a pulse width modulation (PWM) drive signal that drives the inverter. The power system further includes a controller that determines a modulation index associated with the PWM drive signal and injects a harmonic into the PWM drive signal in response to the modulation index exceeding a modulation index threshold value.

Abstract: An electrical device includes a housing defining a chamber, a power converter arranged within the chamber, and a sensor. The sensor includes a coil arranged within the chamber and in radio frequency communication with the power converter to detect partial discharge of a voltage potential applied to the power converter. Health monitoring systems and health monitoring methods are also described.

Abstract: A pulse width modulator (PWM) of a multi-phase power converter is provided. The PWM includes a signal modulator that corresponds to each phase of the converter. Each signal modulator of the PWM is configured to receive a unique triangle carrier signal, receive a unique sine wave signal, compare the received triangle carrier signal and the received sine wave signal, and output at least one control signal based on a result of the comparison. The control signal controls an inverter that applies pulse width modulation to a DC power for converting the DC power to a multi-phase power, AC harmonics of the multi-phase power filtered by a common mode inductor.

Abstract: An AC-DC converter circuit can include a plurality of passive components configured to convert AC to DC and to non-linearly regulate output DC voltage to about a selected maximum throughout an AC input voltage range and/or generator frequency. The plurality of passive components can be configured to also limit power loss as a function of load on a DC side.

Abstract: An electrical device includes a housing defining a chamber, a power converter arranged within the chamber, and a sensor. The sensor includes a coil arranged within the chamber and in radio frequency communication with the power converter to detect partial discharge of a voltage potential applied to the power converter. Health monitoring systems and health monitoring methods are also described.

Abstract: A system includes a first bus bar. A foil element is spaced apart from the first bus bar. The foil element is electrically connected to the first bus bar by grid elements. A second bus bar is spaced apart from the foil element across a dielectric layer. The system can include a second foil element spaced apart from the second bus bar.

Abstract: A system includes a first bus bar. A foil element is spaced apart from the first bus bar. The foil element is electrically connected to the first bus bar by grid elements. A second bus bar is spaced apart from the foil element across a dielectric layer. The system can include a second foil element spaced apart from the second bus bar.

Abstract: An AC-DC converter circuit can include a plurality of passive components configured to convert AC to DC and to non-linearly regulate output DC voltage to about a selected maximum throughout an AC input voltage range and/or generator frequency. The plurality of passive components can be configured to also limit power loss as a function of load on a DC side.

Abstract: A fault detection method includes, at a generator module having a generator, a rectifier connected to the generator by phase leads, and an inverter connected to the rectifier by a direct current (DC) link, receiving a measurement of voltage applied to the rectifier by the phase leads and receiving a measurement of voltage applied to the inverter by the DC link. DC link voltage balance and sequence voltages are calculated using the measurement of voltage applied to the rectifier by the phase leads and the measurement of voltage applied to the inverter by the DC link. Determination is made using the DC link voltage balance and phase sequence voltages when no fault exists in the generator module. Determination is made that a fault condition exists using the DC link voltage balance and phase sequence voltages when a fault exists in the generator module. Generator modules are also described.

Abstract: A fault detection method includes, at a generator module having a generator, a rectifier connected to the generator by phase leads, and an inverter connected to the rectifier by a direct current (DC) link, receiving a measurement of voltage applied to the rectifier by the phase leads and receiving a measurement of voltage applied to the inverter by the DC link. DC link voltage balance and sequence voltages are calculated using the measurement of voltage applied to the rectifier by the phase leads and the measurement of voltage applied to the inverter by the DC link. Determination is made using the DC link voltage balance and phase sequence voltages when no fault exists in the generator module. Determination is made that a fault condition exists using the DC link voltage balance and phase sequence voltages when a fault exists in the generator module. Generator modules are also described.

Abstract: A method of controlling a motor controller includes receiving respective measurements for each of at least three phase currents or voltages output by the motor controller that were instantaneously sensed at substantially the same instant, determining a magnitude of a model signal that models the sensed phase currents or voltages at the instant of the instantaneous sensing as a function of each of the respective measurements, and controlling the motor controller based on the magnitude of the model signal. A motor controller and a controller of a motor controller using the method are also provided.

Abstract: A method of and system for controlling a DC midpoint of a multi-level inverter. The method includes receiving an input power signal from an AC power source at a multi-level motor control system that includes a DC bus and a multi-level inverter configured to supply a load, the DC bus having a DC midpoint, connecting a DC midpoint of a DC bus to a neutral point of the AC power source, while isolating a neutral point of a load supplied by the multi-level inverter from the DC midpoint, monitoring a voltage on the DC midpoint of the DC bus. In addition, the method may include controlling a voltage of the neutral point of the AC load based on imbalances in the load supplied by the multi-level inverter.

Abstract: A heat pipe system includes one or more arcuate heat pipe segments shaped conforming to an inner wall of an engine rotor. The heat pipe system also includes a heat pipe fluid within the one or more arcuate heat pipe segments.

Abstract: A method of and system for controlling a DC midpoint of a multi-level inverter. The method includes receiving an input power signal from an AC power source at a multi-level motor control system that includes a DC bus and a multi-level inverter configured to supply a load, the DC bus having a DC midpoint, connecting a DC midpoint of a DC bus to a neutral point of the AC power source, while isolating a neutral point of a load supplied by the multi-level inverter from the DC midpoint, monitoring a voltage on the DC midpoint of the DC bus. In addition, the method may include controlling a voltage of the neutral point of the AC load based on imbalances in the load supplied by the multi-level inverter.

Abstract: According to an aspect, an inductor damper circuit includes a shared magnetic core, a primary winding, and a secondary winding. The primary winding includes an inductor winding of a first wire gauge wound about the shared magnetic core. The secondary winding includes a resistive damper winding of a second wire gauge that is less than the first wire gauge and wound about the shared magnetic core in contactless magnetic coupling with the primary winding.