A power conversion device includes first and second current detectors. A coil is connected a first power terminal through the first and second current detectors. A first switch has a source terminal connected to the coil and a second semiconductor switch has a drain terminal connected to the coil. A first diode is connected between a drain terminal of the first semiconductor switch and a second power supply terminal. A second diode is connected between a source terminal of the second semiconductor switch and the second power terminal. A capacitor is connected in parallel with the first and second diodes. A control circuit is configured to turn the first and second semiconductor switches on or off based on current detections of the first and second current detectors.

A power conversion system includes a first power conversion port including a three-level power factor correction device and a primary power conversion circuit, a second power conversion port including a three-level rectifier and a third power conversion port including a rectifier, the first power conversion port, the second power conversion port and the third power conversion port magnetically coupled to each other through a transformer.

An image display apparatus is disclosed. The image display apparatus includes a display and a power supply configured to supply driving voltage to the display, wherein the power supply includes a converter to convert input AC voltage into DC voltage and a controller to control the converter, the converter includes a first leg including a first switching device and a second switching device connected to each other in series and a second leg including a first diode and a second diode connected to each other in series, the first diode and the second diode connected to the first leg in parallel, and the controller controls on time of the first switching device to gradually increase from a first level to a second level for a first period for which the input AC voltage rises after a zero crossing point.

A power converting apparatus includes: a reactor including a first end and a second end, the first end being connected to an alternating-current power supply; a rectifier circuit connected to the second end of the reactor and including at least one switching element, the rectifier circuit converting an alternating-current voltage output from the alternating-current power supply into a direct-current voltage; and a detecting unit that detects a physical quantity indicating an operation state of the rectifier circuit, wherein the number of times of switching of the switching element is changed depending on the operation of the rectifier circuit.

The present description concerns a converter comprising an AC-DC conversion stage comprising a first thyristor, a first power supply circuit delivering a first reference voltage between a first node and a second node, and a second power supply circuit delivering a second reference voltage between third and fourth nodes, the cathode of the first thyristor being coupled to the first node of the first power supply circuit by a first switch and being connected to the fourth node, the second power supply circuit comprising a first rectifying element coupled to the second node of the first power supply circuit and coupled to the third node.

According to the integrated power conversion apparatus and method according to the exemplary embodiment of the present disclosure, the on-board battery charger (OBC), the lower voltage battery charger (LDC), and the traction converter (TC) are integrated to convert the power so that all the functions which need to be performed by the power conversion system of the related art can be performed. Further, the number of switches is reduced to increase a power density and not only the number of switches, but also the number of controllers is reduced to improve feasibility.

A control circuit for a power factor correction (PFC) circuit, the control circuit includes a multiplier having first, second, and third multiplier inputs and a multiplier output. The control circuit has an adder having first and second inputs and an output. The first input of the adder is coupled to the multiplier output. The control circuit further includes a root mean square (RMS) calculation circuit configured to determine a square of a root mean square of an input sinusoidal voltage. The RMS calculation circuit has an output coupled to the second multiplier input. An input voltage square calculation circuit is configured to determine a square of the input sinusoidal voltage. The input voltage square calculation circuit has an output coupled to the third multiplier input.

A totem-pole PFC circuit is provided. The totem-pole PFC circuit includes an inductor, a first bridge arm and a second bridge arm. The first bridge arm includes a first switch and a second switch connected in series. A first middle node connected between the first and second switches is coupled to a first terminal of an AC power source through the inductor. The second bridge arm connected to the first bridge arm in parallel includes a third switch and a fourth switch connected in series. A second middle node connected between the third and fourth switches is coupled to a second terminal of the AC power source. When a polarity of the AC power source is changed, a change time of a voltage on the second middle node is longer than a preset time not less than 20 μs.

A controller for a boost power factor correction (PFC) converter. The controller is configured to operate the boost PFC converter in multiple operating modes, including a continuous conduction mode (CCM), a transition mode (TM), and a hybrid mode in which the controller operates the converter in both CCM and TM within a same line cycle. An example controller includes a current control loop and a mode transition circuit. The current control loop is configured to compute an inductor current for each of first and second operation modes, based on a current sample taken, for example, during a boost synchronous rectifier conduction period of the converter. The mode transition circuit includes digital logic circuitry and is configured to generate a pulse indicating that one, two or all three of: zero-voltage switching (ZVS) has been achieved; the synchronous rectifier conduction period is active; and/or one of TM or hybrid mode is active.

An energy storage system can include a battery, a power converter comprising a first plurality of switching devices coupled to the battery and a second plurality of switching devices coupled between the first plurality of switching devices and an AC power system, and control circuitry that determines whether the AC power system is a single/split phase system or a three phase system and operates the first and second pluralities of switching devices accordingly. The control circuitry can include a microcontroller and a plurality of voltage sensors each configured to monitor a magnitude and a phase of a voltage to allow the control circuitry to determine whether the AC power system is a single/split phase system or a three phase system and whether the AC power system is connected with a line to line or line to neutral fault condition