Abstract: A multi-level converter includes a first multi-phase inverter and a second multi-phase inverter. The first multi-phase inverter includes a first direct current (DC) positive line, a first DC negative line, and a first plurality of alternating current (AC) lines. Each AC line of the first plurality of AC lines is configured to be connected to a single phase winding of an electric machine. Each single phase winding is connected to a common neutral connector in a Y-winding configuration or between a pair of single phase windings in a ?-winding configuration. The second multi-phase inverter includes a second DC positive line, a second DC negative line, and a second plurality of AC lines and is connected in a similar manner to the first multi-phase inverter. The first DC negative line is electrically coupled to the second DC positive line to connect the first multi-phase inverter and the second multi-phase inverter in series.

Abstract: A multi-level converter includes a first multi-phase inverter and a second multi-phase inverter. The first multi-phase inverter includes a first direct current (DC) positive line, a first DC negative line, and a first plurality of alternating current (AC) lines. Each AC line of the first plurality of AC lines is configured to be connected to a single phase winding of an electric machine. Each single phase winding is connected to a common neutral connector in a Y-winding configuration or between a pair of single phase windings in a ?-winding configuration. The second multi-phase inverter includes a second DC positive line, a second DC negative line, and a second plurality of AC lines and is connected in a similar manner to the first multi-phase inverter. The first DC negative line is electrically coupled to the second DC positive line to connect the first multi-phase inverter and the second multi-phase inverter in series.

Abstract: Methods and apparatus for a dc-dc converter for operating at substantially fixed switching frequency, the converter including a rectifier, and a resonant inverter coupled to the rectifier, the resonant inverter including a switch and a reactive network having first, second, third and fourth energy storage elements, wherein an impedance magnitude at the output of the switch due to the reactive network has minima at dc and at a frequency near a second harmonic of the switching frequency.

Abstract: A resistance compression network substantially decreases the variation in effective resistance seen by a tuned rf inverter as loading conditions change. Circuits can include resistance compression networks and rectifiers to form rf-to-dc converters having narrow-range resistive input characteristics.

Abstract: Methods and apparatus for a dc-dc converter for operating at substantially fixed switching frequency, the converter including a rectifier, and a resonant inverter coupled to the rectifier, the resonant inverter including a switch and a reactive network having first, second, third and fourth energy storage elements, wherein an impedance magnitude at the output of the switch due to the reactive network has minima at dc and at a frequency near a second harmonic of the switching frequency.

Abstract: A resistance compression network substantially decreases the variation in effective resistance seen by a tuned rf inverter as loading conditions change. Circuits can include resistance compression networks and rectifiers to form rf-to-dc converters having narrow-range resistive input characteristics.