A load control device for controlling power delivered from an alternating-current power source to an electrical load may comprise a controllably conductive device, a control circuit, and an overcurrent protection circuit that is configured to be disabled when the controllably conductive device is non-conductive. The control circuit may be configured to control the controllably conductive device to be non-conductive at the beginning of each half-cycle of the AC power source and to render the controllably conductive device conductive at a firing time during each half-cycle (e.g., using a forward phase-control dimming technique). The overcurrent protection circuit may be configured to render the controllably conductive device non-conductive in the event of an overcurrent condition in the controllably conductive device. The overcurrent protection circuit may be disabled when the controllably conductive device is non-conductive and enabled after the firing time when the controllably conductive device is rendered conductive during each half-cycle.

Controller and method for a power converter. For example, a controller for a power converter includes: a first terminal configured to receive a first terminal voltage; a second terminal configured to receive a second terminal voltage; a comparator configured to receive a first threshold voltage and the second terminal voltage and to generate a comparison signal based at least in part on the first threshold voltage and the second terminal voltage; and a switch configured to receive the first terminal voltage and the comparison signal, the switch being further configured to be closed to allow a current to flow out of the second terminal through the switch if the comparison signal is at a first logic level; wherein the comparator is further configured to: receive a first reference voltage as the first threshold voltage if the first terminal voltage is smaller than a second threshold voltage.

Controller and method for a power converter. For example, a controller for a power converter includes: a first terminal configured to receive a first terminal voltage; a second terminal configured to receive a second terminal voltage; a comparator configured to receive a first threshold voltage and the second terminal voltage and to generate a comparison signal based at least in part on the first threshold voltage and the second terminal voltage; and a switch configured to receive the first terminal voltage and the comparison signal, the switch being further configured to be closed to allow a current to flow out of the second terminal through the switch if the comparison signal is at a first logic level; wherein the comparator is further configured to: receive a first reference voltage as the first threshold voltage if the first terminal voltage is smaller than a second threshold voltage.

A system includes an alternating current (AC) bus. An active rectifier is connected to receive alternating current from the AC bus. An exciter inductor coil is connected to receive direct current (DC) output from the active rectifier. A method includes performing current control on an alternating current (AC) bus to output DC current to an exciter inductor coil.

A system includes an alternating current (AC) bus. An active rectifier is connected to receive alternating current from the AC bus. An exciter inductor coil is connected to receive direct current (DC) output from the active rectifier. A method includes performing current control on an alternating current (AC) bus to output DC current to an exciter inductor coil.

The disclosure features circuits and methods for protecting transistors of a wireless power receiver, which can be controlled by gate drivers powered by an auxiliary power source. The circuit can include a comparator configured to generate a signal indicating a comparison of a value of the auxiliary power source to a predetermined threshold, and a fault latch coupled to the comparator. The fault latch can be configured to trigger based on the generated signal and transmit a signal to respective inputs of the gate drivers to cause a latched-on state of respective gates of the transistors. Switches respectively coupled to the gate drivers can be configured to disconnect respective outputs of the gate drivers from the respective transistor gates. Gate hold-up circuits respectively coupled to the respective transistor gates can be configured to maintain the latched-on state of the respective transistor gates for a period of time.

A power converter according to the present disclosure includes a cooling plate and a plurality of circuit elements. The cooling plate includes a first cooling surface and a second cooling surface on an opposite side from the first cooling surface. The cooling plate is provided with a through hole passing through between the first and second cooling surfaces. The circuit elements convert AC power supplied from an external power source into DC power of a certain voltage and output the DC power. The circuit elements at least include first and second circuit elements. The first circuit element includes a first terminal and is thermally connected to the first cooling surface. The second circuit element includes a second terminal electrically connected to the first terminal and inserted into the through hole, and is thermally connected to the second cooling surface.

A power converter according to the present disclosure includes a cooling plate and a plurality of circuit elements. The cooling plate includes a first cooling surface and a second cooling surface on an opposite side from the first cooling surface. The cooling plate is provided with a through hole passing through between the first and second cooling surfaces. The circuit elements convert AC power supplied from an external power source into DC power of a certain voltage and output the DC power. The circuit elements at least include first and second circuit elements. The first circuit element includes a first terminal and is thermally connected to the first cooling surface. The second circuit element includes a second terminal electrically connected to the first terminal and inserted into the through hole, and is thermally connected to the second cooling surface.

This disclosure describes systems, methods, and apparatus for waveform control, comprising: a power supply having an input terminal, and at least one output terminal for coupling to a load; a controller; a variable inductor coupled to at least one of the output terminals, the variable inductor comprising a first magnetic core having a plurality of arms, including at least a first inductor arm and a first control arm, wherein an inductance winding having one or more turns is wound around the first inductor arm, and wherein a first control winding comprising one or more turns is wound around the first control arm; and a DC current source coupled to the first control arm and the controller, the controller configured to adjust a DC bias applied by the DC current source to the first control arm to control an output waveform at the at least one output terminal.

This disclosure describes systems, methods, and apparatus for waveform control, comprising: a power supply having an input terminal, and at least one output terminal for coupling to a load; a controller; a variable inductor coupled to at least one of the output terminals, the variable inductor comprising a first magnetic core having a plurality of arms, including at least a first inductor arm and a first control arm, wherein an inductance winding having one or more turns is wound around the first inductor arm, and wherein a first control winding comprising one or more turns is wound around the first control arm; and a DC current source coupled to the first control arm and the controller, the controller configured to adjust a DC bias applied by the DC current source to the first control arm to control an output waveform at the at least one output terminal.