A power interrupter device includes a solid-state bidirectional switch and control circuitry to control the solid-state bidirectional switch. The bidirectional switch is connected between input and output terminals of the power interrupter device. The control circuitry includes driver circuitry and fault detection circuitry. The driver circuitry generates a regulated direct current (DC) voltage using current drawn from an input power source applied to the input terminal and applies the regulated DC voltage to a control input of the bidirectional switch. The fault detection circuitry is configured to sense a level of load current flowing in an electrical path between the input and output terminals, to detect an occurrence of a fault condition based on the sensed load current level, and to short the control input of the bidirectional switch to place the bidirectional switch in a switched-off state, in response to detecting the occurrence of a fault condition.

An AC-DC power supply receives input AC power and outputs DC power. The converter includes a high power factor bridge rectifier, a barrier circuit with resistor(s) and capacitor(s), and a step-down switching DC-DC converter to step-down a first DC voltage to a second, lower, DC voltage for output. Additionally, fault-protection is provided by redundancy in diodes on diode legs of a bridge rectifier and capacitor(s) of a filter circuit thereof, and a fault-protection circuit to sense current from a step-down switching DC-DC converter, a first voltage from the step-down switching DC-DC converter, and/or a second voltage at an output of the step-down switching DC-DC converter, and open the circuit on a fault.

This control device is configured to control a converter comprising a piezoelectric element and several switches, and capable of delivering N output voltage(s) from of E input voltage(s), E≥1, N≥1.

The control device comprises a module for controlling, during a respective resonance cycle of the piezoelectric element, switching of the switches to alternate phases at substantially constant voltage and phases at a substantially constant charge at the terminals of the piezoelectric element, each cycle comprising first and second half-cycles, a current flowing in one direction in the piezoelectric element during first half-cycle and in an opposite direction during the second half-cycle.

The number of substantially constant voltage phases during a cycle is greater than or equal to E+N+2, and each of the half-cycles comprises at least two substantially constant voltage phases.

The present disclosure provides a conversion circuit including a power supply module, positive and negative input terminals, positive and negative output terminals, a switch, an inductor, input and output capacitors, and a controller. The power supply module converts an AC power for providing three potentials on three power supply terminals respectively. The potential on the first power supply terminal is higher than the potential on the second power supply terminal, which is higher than the potential on the third power supply terminal. The positive and negative input terminals are electrically connected to the first and third power supply terminals respectively, and a voltage therebetween is an input voltage. The negative output terminal is electrically connected to the third power supply terminal. The controller is electrically connected to the positive input terminal, the second power supply terminal and the switch. A voltage across the controller is lower than the input voltage.

Systems and methods for a capacitive coupler for high-voltage step-down include an actively-controlled current-steering circuit connected in series with a current-limiting capacitor in order to transform a higher and potentially variable AC voltage to a lower regulated DC voltage. The actively-controlled current-steering circuit includes a switching element which, during operation, is predominantly either fully open or fully closed, and comparatively spends only a small fraction of operating time in a transition-state between the open and closed positions.

The present disclosure provides a method and apparatus using a novel PWM switching technique that requires only one PWM carrier signal and benefits from two logic functions to provide switching signals and provides the flying capacitor (FC) voltage as well as dc-link capacitors voltages regulated to their desired values without external control. It may also, eliminate the odd multiples of the switching harmonic clusters from the output voltage is possible; double the frequency of first switching harmonic; reduce filtering efforts may be required since the values of the output LC filter inductor and capacitor can be very much reduced. Furthermore, notable reduction in control complexity is possible using the novel PWM method.

A single-phase and three-phase compatible AC-DC conversion circuit includes a first switching component, a second switching component, a third switching component, three switch bridge arms, a fourth switching component, a pre-charge resistor, a capacitor assembly, and a control unit. Each switch bridge arm has an upper switch and a lower switch connected in series. The fourth switching component is coupled between a first phase of a three-phase power source and a common-connected node of the switch bridge arm corresponding to a second phase of the three-phase power source. The control unit turns on the fourth switching component, turns on the upper switch coupled to the first switching component, and turns on the lower switch coupled to the fourth switching component to provide a discharge path so that the capacitor assembly discharges through the pre-charge resistor on the discharge path.

A resonant inductive power transfer circuit has a power converter to supply to a load, and the converter is concurrently controlled to create a controlled reactance that substantially compensates for variability in the coupling with the another resonant inductive power transfer circuit and/or changes in the load supplied by the power converter.

A power supply circuit of a step-down type, configured to generate an output voltage at a predetermined level from an alternating current (AC) voltage. The power supply circuit includes a rectifier circuit configured to rectify the AC voltage, a first line coupled to the rectifier circuit, a second line on a ground side, a switch coupled between the first line and the second line, and a control circuit configured to control the switch to bring a level of the output voltage to the predetermined level. The power supply circuit is free of an inductor interposed between the first line and the rectifier circuit.

A power supply device includes a transformer including a primary winding, a secondary winding and an auxiliary winding, first, second and third circuits, and a switch. The first circuit in which a first capacitor and a first rectifier are connected in series is connected to the primary winding in parallel. The switch of which one end is connected to one end of the primary winding. The second circuit in which the auxiliary winding and a second rectifier are connected in serial is connected between a connecting point, to which the first capacitor and the first rectifier are connected, and the other end of the switch. The third circuit including a resistor and a third rectifier is connected to a gate of the switch. In the third circuit, a resistance value in a direction where a current flows into the gate of the switch is smaller than that in a direction where the current flows out of the gate.