A lighting system includes two or more lighting fixtures, each comprising a housing, at least one light source mechanically supported by the housing, at least one pipe thermally coupled to the housing to carry a fluid coolant, an AC power port, and at least one network communications port. The AC power ports of respective lighting fixtures are coupled together with a plurality of industrial power cables without using one or more conduits for the plurality of industrial power cables. The network communications ports of the respective lighting fixtures are coupled together with a plurality of waterproof network communications cables. In one example, a lighting system kit comprises two or more lighting fixtures having an AC power port comprising an industrial type connector. The kit further comprises multiple industrial power cables and one or more industrial drop tee cables.

A direct charging method is provided that alerts a mobile device when a switching power converter is operating in a constant-current mode to alert the mobile device of an output current without the use of a secondary-side current sense resistor.

An electronic half-bridge ZETA converter may include a transformer, wherein a half-bridge is connected to the primary winding of transformer, and wherein a respective capacitance and a respective diode are associated with the half-bridge switches. Moreover, the converter includes a ZETA converter which is connected to secondary winding of transformer, so that the ZETA converter includes a first inductance, which includes the magnetization inductance of transformer, and a second inductance. Finally, the converter includes a control unit which drives the half-bridge switches with four time intervals that are repeated periodically. Specifically, during the fourth time interval the first and the second switch are opened, so that the capacitance associated with said second switch is charged and the capacitance associated with said first switch is discharged, enabling a zero voltage switching.

System and method for managing a cumulative DC offset in a magnetizable material. A primary driving AC voltage and a magnetic flux sensor. The flux sensor output is continuously received into memory while the the flux sensor output for each phase half-cycle is processed to continuously compute and re-compute in real time a flux-second integral for each half-cycle. The two half-cycle flux-second integrals are compared to each other for a DC offset value and the offset value drives a slow loop DC compensation circuit to steer a PWM control.

Disclosed is a power converter including a generator configured to generate a sequence of output voltage waveforms, a resonant tank connected to the generator comprising at least one capacitor and at least one inductor, a transformer including a primary side connected in series with said series inductor and, the primary side being configurable to use at least one primary winding tap and a secondary side for connecting to a rectifying circuit for providing a rectified DC voltage to an output load circuit, a first switch and a second switch on the primary side connected to the primary winding, wherein the at least one primary winding is selected by the first switch or the second switch to select a different reflected output voltage by closing the first switch or the second switch.

A step-up/down DC converter applied to achieve a characteristic of zero-ripple voltage, which ripple voltage is near zero, is disclosed. The converter includes a ripple-filtering inductor, a power isolating and converting unit, a power switch, a first inductor, a first capacitor, a second capacitor, and a rectifying switch. The power isolating and converting unit comprises windings for isolation an input stage connected to a power source from an output stage connected to a load. The power switch, the first inductor, and the first capacitor are arranged at the input stage, and the second capacitor and the rectifying switch are arranged at the output stage. The ripple-filtering inductor, which may be arranged at the input or output stage, and the first inductor divide the power supplied from the power source, thus the voltage drop of the first inductor is reduced for smoothing the ripple voltage at the output stage.

A method and a device for supplying energy to a low-voltage load using an electronic power supply device. The method involves: a) setting the power supply device to be able to provide an output current to the low-voltage load up to a specified peak current value upon demand; b) monitoring the output current (I.sub.L) provided to the low-voltage load by the electronic power supply device to detect an increase of I.sub.L over a threshold (I.sub.N) which is lower than the peak current value, c) if an increase of I.sub.L to an increased output current value higher than I.sub.N is detected, detecting the increased I.sub.L value and ascertaining an output current pulse duration (t.sub.Pulse) based on the increased current value; d) providing I.sub.L at the level of the increased current value for the duration of the ascertained t.sub.Pulse; and e) providing the I.sub.L at the level of I.sub.N after t.sub.Pulse has expired.

A split drive transformer (SDT) and use of such a transformer in a power converter is described. The power converter includes a power and distributor circuit configured to receive one or more input signals and provides multiple signals to a first side of the SDT. The SDT receives the signals provided to the first side thereof and provides signals at a second side thereof to a power combiner and rectifier circuit which is configured to provide output signals to a load. In some embodiments, the SDT may be provided as a switched-capacitor (SC) SDT. In some embodiments, the power converter may optionally include a level selection circuit (LSC) on one or both of the distributor and combiner sides.

In some embodiments, an inductor-inductor-capacitor (LLC) converter includes a transformer having a primary winding, a secondary winding, and an auxiliary winding. The primary winding is coupled to a primary side circuit and the auxiliary winding has a first winding portion coupled between a first terminal and a middle terminal, and a second winding portion coupled between the middle terminal and a second terminal. The LLC converter further includes a first diode coupled between the first terminal and a first node, a second diode coupled between the second terminal and the first node, and a switch coupled between the first node and a reference voltage terminal. The middle terminal of the auxiliary winding is coupled to the reference voltage terminal.

A power converter circuit includes a power stage that includes a transformer and a switch. The switch can be controlled in response to a PWM signal to provide a primary current through a primary winding of the transformer to induce a secondary current in a secondary winding of the transformer to generate an output voltage. The power stage includes a switching node between the switch and the primary winding having a switching voltage. The circuit also includes a switching controller configured to generate the PWM signal in response to a ramp signal. The ramp signal can have an amplitude of a slope that is proportional to a decay rate of a magnetizing current of the transformer and generated in response to feedback from the power stage. The switch can be activated in response to the switching voltage having an amplitude of approximately zero volts based on the amplitude of the ramp signal.