For open loop phase pre-charge, an apparatus includes a Switching Mode Power Supply (SMPS) charging diode and a charge generator. The SMPS charging diode pre-charges an SMPS to a regulation set point from at least one phase of an Alternating Current (AC) voltage. The charge generator is powered by the pre-charged SMPS. In response to detecting the regulation set point iteratively, the charge generator detects a specified phase angle of the AC voltage. In response to the specified phase angle, the charge generator iteratively generates a charging voltage during positive voltage interval that charges a Direct Current (DC) bus capacitor to a target DC bus voltage within a charging time interval. At least a portion of the charge generator comprises one or more of hardware and executable code, the executable code stored on one or more computer readable storage media.

A control device includes a triac and a first diode that is series-connected between the triac and a first terminal of the device that is configured to be connected to a cathode gate of a thyristor. A second terminal of the control device is configured to be connected to an anode of the thyristor. The triac has a gate connected to a third terminal of the device that is configured to receive a control signal. The thyristor is a component part of one or more of a rectifying bridge circuit, an in-rush current limiting circuit or a solid-state relay circuit.

A smart-home device may include an energy-storage element that stores energy harvested from an environmental system; a power wire connector and a return wire connector; and switching elements configured to operate in a first state where the switching elements create a connection between the power and the return; and a second state where the switching elements interrupt the connection between the power and return. The smart-home device may also include a circuit that controls the switching elements, where the circuit is configured to detect a zero-crossing of a current received through the power wire connector; wait for a first time interval after the zero-crossing is detected; after an expiration of the first time interval, enable active power stealing for a second time interval; and after an expiration of the second time interval, disable active power stealing.

An apparatus attachable to a luminaire includes circuitry for converting alternating current power into direct current (DC) power and providing a digitally stable ground for operation of a processor-based device. The circuitry includes a transformer isolating a primary side from a secondary side of the circuitry. A switching controller (e.g., a pulse width modulation controller) on the primary side directs a switching circuit to selectively permit current flow through a primary side of the transformer to a first ground node. A secondary winding of the transformer sources a rectified DC output relative to a second ground node that is isolated from the first ground node. In some cases, compensation on the secondary winding side provides isolated feedback to the controller, such as via an optical isolator. The controller directs the switching circuit based at least partially on the feedback and input from an auxiliary winding of the transformer.

A power conversion system includes: a power converter connected between a DC power source and an AC power source; an AC switch connected between the power converter and the AC power source; an AC capacitor connected on the power converter side relative to the AC switch, on an output side of the power converter; and a control device configured to, in a state in which the AC switch is open, recognize a voltage of the AC capacitor and control the power converter to bring an output voltage of the power converter close to a voltage of the AC power source from the voltage of the AC capacitor gradually or in a step-by-step manner, and then close the AC switch. The power conversion system can suppress overcurrent at a time of start-up of a power converter and inrush current at a time of interconnection to an AC power source.

A converter circuit includes first and second input terminals, control circuitry, and a storage capacitor. The first and second input terminals are configured for connection to an AC power supply to receive an AC signal. The control circuitry is coupled to the first and second input terminals. A terminal of the storage capacitor is coupled to an output node of the control circuitry. The storage capacitor is charged by the control circuitry and configured for use as a DC power source. The control circuitry is configured to couple the first input terminal to the storage capacitor during a portion of a positive half-cycle of the input AC signal to charge the storage capacitor and to decouple the first input terminal from the storage capacitor during an entirety of each negative half-cycle of the input AC signal, to thereby prevent discharging of the storage capacitor by the input AC signal.

A circuit is provided for converting alternating current power into direct current (DC) power and providing a digitally stable ground for operation of a processor-based device. Embodiments of the circuit include a transformer isolating (e.g., via galvanic isolation) a primary side from a secondary side of the circuit. A controller (e.g., a pulse width modulation (PWM) controller) on the primary side directs a switching circuit to selectively permit current flow through a primary side of the transformer to a first ground node on the primary side. A secondary winding of the transformer sources a rectified DC output relative to a second ground node that is isolated from the first ground node. In some cases, compensation on the secondary winding side provides isolated feedback to the controller via an optical isolator or some other circuit. The controller directs the switching circuit based at least in part on the error correction feedback and input from an auxiliary winding of the transformer.

An outboard motor includes a power converter to convert AC power generated by a generator that generates power by operation of a drive engine into DC power and to supply converted DC power to a plurality of batteries, a voltage detector to detect a voltage value of the DC power converted by the power converter, and a phase angle controller configured or programmed to perform a retarding/advancing control until the voltage value of the DC power becomes equal to or higher than a first preset voltage value, which is higher than a voltage value at a start of the retarding/advancing control.

The instant disclosure concerns a power converter including: a primary stage (110) including at least one first cut-off switch (S.sub.11, S.sub.12, S.sub.13, S.sub.14); a control circuit (112) capable of applying a first control signal to said at least ore first switch; a secondary stage (130) including at least one second cut-off switch (S.sub.21, S.sub.22, S.sub.23, S.sub.24); a control circuit (132) capable of applying a second control signal to said at least one second switch; a power transmission stage (120) coupling the primary stage (110) to the secondary stage (130), wherein the control circuit (132) of the secondary stage is electrically isolated from the control circuit (112) of the primary stage.

A high voltage generator is provided. The high voltage generator includes an inverter circuit coupled to receive a direct-current (DC) input voltage, a resonant circuit coupled to the inverter circuit, a transformer coupled to the resonant circuit and also coupled to provide a high voltage output to a high voltage device, and a phase control circuit coupled to receive a voltage across and a current through the resonant circuit and also coupled to the inverter circuit. The phase control circuit generates control signals to drive the inverter circuit. The control signals drive the inverter circuit to keep the resonant circuit operating in an inductive region.