Abstract: A three-level zeta asymmetrical half-bridge for converting a DC input voltage into a DC output voltage comprising an asymmetrical half-bridge, a resonant tank and a zeta converter.

Abstract: A snubber circuit to mitigate voltage overshoot in a power train for driving a motor, the snubber circuit configured to be connected to the motor terminal between a transmission line from a power supply and converter and a motor. The snubber circuit includes a rectifier, a capacitor connected across an output of the rectifier and a load connected across the capacitor. The capacitor is rated to charge to a predetermined link voltage and wherein an input voltage to the rectifier that exceeds the link voltage causes the voltage at the motor terminal to clamp to the link voltage and for excess energy from the input voltage to be stored in the link capacitor and dissipated by the load.

Abstract: A hybrid switched-capacitor power converter for converting an input voltage into an output voltage. The power converter includes: an input voltage source configured to provide the input voltage, an output capacitor connected across a load, at least two inductors arranged in parallel branches of a circuit element between the input voltage source and the load, at least one switched capacitor connected between the parallel branches of the circuit element, and at least two switches operable to selectively charge and discharge the at least one switched capacitor and the at least two inductors. The power converter is configured to be operated in a switching cycle such that, at different stages in the switching cycle, the inductors and switched capacitor are selectively charged and discharged.

Abstract: A filter for a motor drive includes a plurality of phase lines configured to connect an output of a power source to an input of a motor. The power source is configured to supply at the output a voltage that switches between a high voltage state and a low voltage state. The filter includes a plurality of capacitors, where each capacitor is connected between one of the plurality of phase lines and a ground. The filter further includes a plurality of primary inductors, where each phase line includes one of the plurality of primary inductors. The filter includes a plurality of secondary inductors and a plurality of resistors. Each secondary inductor is connected in series with one of the plurality of resistors and each primary inductor is connected in parallel to one of the plurality of secondary inductors and one of the plurality of resistors.

Abstract: A method of implementing a space vector pulse width modulation scheme. The method includes: mapping switching states for an n-phase, where n is an integer, multi-level inverter onto a two-dimensional hexagonal space vector diagram; identifying redundant vectors in the space vector diagram and removing redundant vectors associated with a common mode voltage current contribution of more than a predetermined threshold; identifying a location in the space vector diagram of a voltage reference vector; identifying a sector of the space vector diagram defined by four vectors within which the voltage reference vector is located; and determining duty cycles and switching states associated with the four vectors to synthesise the voltage reference vector.

Abstract: An n-level flying capacitor multi-level buck converter, for converting a DC input voltage into a DC output voltage provided at a load. The n-level flying capacitor multi-level buck converter is configured to: operate a first and second pairs of switching elements in a sequence to selectively apply a portion of the input voltage across the output filter; and operate the first and second pairs of switching elements such that each switching element turns on when a voltage across the switching element is zero.

Abstract: A three-level zeta asymmetrical half-bridge for converting a DC input voltage into a DC output voltage comprising an asymmetrical half-bridge, a resonant tank and a zeta converter.

Abstract: A filter (8) for a motor drive, including a plurality of phase lines (10a-c) configured to connect an output of a power source (4, 6) to an input of a motor (2). The power source (4, 6) is configured to supply at the output a voltage that switches between a high voltage state and a low voltage state. The filter (8) includes a plurality of capacitors (12a-c), wherein each capacitor (12a-c) is connected between one of the plurality of phase lines (10a-c) and a ground. The filter (8) further includes a plurality of primary inductors (14a-c), wherein each phase line (10a-c) comprises one of the plurality of primary inductors (14a-c). The filter (8) further includes a plurality of secondary inductors (16a-c) and a plurality of resistors (18a-c).

Abstract: A hybrid switched-capacitor power converter for converting an input voltage into an output voltage. The power converter includes: an input voltage source configured to provide the input voltage, an output capacitor connected across a load, at least two inductors arranged in parallel branches of a circuit element between the input voltage source and the load, at least one switched capacitor connected between the parallel branches of the circuit element, and at least two switches operable to selectively charge and discharge the at least one switched capacitor and the at least two inductors. The power converter is configured to be operated in a switching cycle such that, at different stages in the switching cycle, the inductors and switched capacitor are selectively charged and discharged.

Abstract: In accordance with at least one aspect of this disclosure, a converter system for a three level boost converter. In embodiments, the system includes a voltage input configured to connect to a voltage source, a switching module operatively connected to the voltage input to output quasi-square wave, a voltage output configured to supply voltage to a load, and a logic module. In embodiments, the logic module can be configured to control the switching module to modulate voltage from the voltage source to the voltage output to maintain a zero-voltage switching condition for at least a specified interval, using a method.

Abstract: A snubber circuit to mitigate voltage overshoot in a power train for driving a motor, the snubber circuit configured to be connected to the motor terminal between a transmission line from a power supply and converter and a motor. The snubber circuit includes a rectifier, a capacitor connected across an output of the rectifier and a load connected across the capacitor. The capacitor is rated to charge to a predetermined link voltage and wherein an input voltage to the rectifier that exceeds the link voltage causes the voltage at the motor terminal to clamp to the link voltage and for excess energy from the input voltage to be stored in the link capacitor and dissipated by the load.

Abstract: A zero voltage transition, ZVT, auxiliary circuit for a multi-level power converter. The ZVT auxiliary circuit includes first and second solid state auxiliary switches connected in series across a series connection of an input voltage and an input inductor, and an auxiliary inductor Laux connected at one end between the first and second solid state auxiliary switches, the other end being arranged to be connected between two switching stages of the multi-level power converter, in use.

Abstract: A series resonant power converter, comprising: a first plurality, m, of resonant power converter modules, each comprising a switching stage, a resonant tank, a transformer, a rectifier stage and an output capacitor, the plurality of resonant power converter modules connected in series across a power supply, the resonant power converter further comprising a common output stage (500) connected across the series-connected plurality of resonant power converter modules, whereby a second plurality, n, of output levels at the common output stage.

Abstract: An active electromagnetic interference filter comprising an adjustable shunt impedance circuit, the adjustable shunt impedance circuit comprising a noise sensing branch that senses input noise and provides a noise voltage representative of the sensed noise, and an operational amplifier stage configured to generate, at an injection branch, an injection current based on the noise voltage.