Abstract: A device includes a rotor and a stator with coils arranged to form a phase element. The phase element includes a first coil group including a first coil and a second coil and a second coil group including a third coil and a fourth coil, where the rotor is positioned between the first coil group and the second coil group. The device also includes one or more switches that enable reconfiguration of the phase element by switching an electrical configuration of the coils. In a first mode, the coils are arranged with the first coil in a first coil path and the second coil in a second coil path that is coupled in parallel with the first coil path. The coils are arranged such that a voltage generated across the first coil path is substantially equal to a voltage generated across the second coil path.

Abstract: A device includes a rotor and a stator with coils arranged to form a phase element. The phase element includes a first coil group including a first coil and a second coil and a second coil group including a third coil and a fourth coil, where the rotor is positioned between the first coil group and the second coil group. The device also includes one or more switches that enable reconfiguration of the phase element by switching an electrical configuration of the coils. In a first mode, the coils are arranged with the first coil in a first coil path and the second coil in a second coil path that is coupled in parallel with the first coil path. The coils are arranged such that a voltage generated across the first coil path is substantially equal to a voltage generated across the second coil path.

Abstract: Reference signals are combined with a chop frequency signal in a pulse width modulator (PWM) to provide plural inputs to a multi-phase H-bridge amplifier. Also provided to the bridge amplifier is a high voltage DC input which is converted by the pulsed inputs to the bridge amplifier to a variable AC voltage for driving a motor. The AC drive voltage is also provided to a variable frequency voltage-controlled oscillators (VCOs) in a feedback arrangement, with the variable frequency VCO outputs heterodyned with each of plural outputs of a multi-phase ring oscillator to provide plural baseband signals having a constant phase relationship at a high frequency. The baseband signals form the aforementioned reference signals provided to the PWM in the feedback arrangement with closed loop control and frequency and phase discrimination using phase lock loop techniques for synchronous motor control over a range of DC-100 kHz with 0-25 MHz VCOs.

Abstract: Reference signals are combined with a chop frequency signal in a pulse width modulator (PWM) to provide plural inputs to a multi-phase H-bridge amplifier. Also provided to the bridge amplifier is a high voltage DC input which is converted by the pulsed inputs to the bridge amplifier to a variable AC voltage for driving a motor. The AC drive voltage is also provided to a variable frequency voltage-controlled oscillators (VCOs) in a feedback arrangement, with the variable frequency VCO outputs heterodyned with each of plural outputs of a multi-phase ring oscillator to provide plural baseband signals having a constant phase relationship at a high frequency. The baseband signals form the aforementioned reference signals provided to the PWM in the feedback arrangement with closed loop control and frequency and phase discrimination using phase lock loop techniques for synchronous motor control over a range of DC-100 kHz with 0-25 MHz VCOs.

Abstract: A loop resistance tester (LRT) for shield integrity testing comprising three elements: a “drive” current coupler, a “sense” current coupler, joint probes, and an instrument assembly. A low-power excitation current is sent from the instrument into the drive coupler, which is essentially a transformer. This induces a current in the electrical cable under test, as long as that cable and the connected structure form a continuous current path, or loop. This induced loop current is detected by the “sense” current coupler (transformer) and is measured by the instrument. The ratio of the loop voltage to loop current, as phasor values, gives the complex loop impedance, the real part of which is the loop resistance.