A switched capacitor voltage converter circuit includes: a switched capacitor converter and a control circuit; wherein the control circuit adjusts operation frequencies and/or duty ratios of operation signals which control switches of the switched capacitor converter, so as to adjust a ratio of a first voltage to a second voltage to a predetermined ratio. When the control circuit decreases the duty ratios of the operation signals, if a part of the switches of the switched capacitor converter are turned ON, an inductor current flowing toward the second voltage is in a first state; if the inductor current continues to flow via a current freewheeling path, the inductor current flowing toward the second voltage becomes in a second state. A corresponding inductor is thereby switched between the first state and the second state to perform inductive power conversion.

A controller IC for a resonant switched capacitor converter includes a drive circuit and a frequency controller. The frequency controller controls a switching frequency based on an output voltage of the resonant switched capacitor converter.

A power converter includes: a switching transistor, a transformer, a control circuit; the control circuit is configured to determine a target voltage in a process that the switching transistor is driven to conduct; the target voltage can represent a voltage change of an input terminal of the switching transistor; when the target voltage starts to drop but is higher than a reference voltage, drive a control terminal of the switching transistor with a first driving current; when the target voltage decreases to be lower than the reference voltage, drive the switching transistor with a second driving current; the second driving current is higher than the first driving current; the switching transistor is driven by the first driving current for part or all of the time before entering the Miller plateau stage, and is driven by the second driving current after starting to enter the Miller plateau stage.

A cascaded power electronic transformer and a method for controlling the same are provided. The method includes: calculating electrical angles θ.sub.i1 and θ.sub.kps of an s.sup.th transformer and a compensation electrical angle θ.sub.j of a j.sup.th transformer; adding the compensation electrical angle θ.sub.j to the electrical angle θ.sub.kps of the j.sup.th transformer, to obtain a compensated electrical angle θ.sub.kps of the j.sup.th transformer; and calculating a square wave of a bridge arm voltage of each of the m primary converters and the r secondary converters of the s.sup.th transformer based on the electrical angle θ.sub.i1 and the electrical angle θ.sub.kps of the s.sup.th transformer after compensation.

A switched-capacitor DC/DC converter, a switching-mode power supply, and a control method. The switched-capacitor DC/DC converter includes a controllable switch and n switched capacitor modules, where the n switched capacitor modules are connected in series to form a voltage conversion branch circuit, and the voltage conversion branch circuit is connected to the controllable switch in series. n is an integer greater than or equal to 1. When the DC/DC converter implements different voltage conversion ratios, n may be different values. The converter can implement voltage step-down or voltage step-up, and does not include a transformer inside.

A power converter includes two arms for each phase between DC terminals, and each arm is formed by connecting a plurality of converter cells in series. A control device includes an arm voltage command generation unit which generates, for each arm, an arm voltage command for the plurality of converter cells. The arm voltage command is generated by superimposing a zero-phase-sequence voltage command having a frequency component that is three times an AC fundamental frequency. Phase adjustment of the zero-phase-sequence voltage command is performed on the basis of voltage of a DC capacitor in the converter cell and the arm voltage command.

Provided is a control circuit configured to control a switching element of a switching power source, the control circuit comprising: a first protection unit configured to stop a principal current flowing through the switching element when the principal current of the switching element has exceeded a first threshold value; and a second protection unit configured to stop the principal current of the switching element over a longer time period than the first protection unit when the principal current has exceeded a second threshold value larger than the first threshold value. The first protection unit may shorten a pulse width of a control pulse in one cycle of an oscillation signal, and the second protection unit may fix the switching element to the off-state over a plurality of cycles of the oscillation signal.

A method for operating a hybrid rectifier includes an AC input, a DC output and a thyristor rectifier arranged in a first path, and a transistor rectifier arranged in a second, parallel path. The method includes when a DC voltage at the DC output of the hybrid rectifier is below a voltage threshold value, operating the hybrid rectifier in a first operating state in which the transistor rectifier is isolated from the DC output and connected to the AC input and the thyristor rectifier is connected both to the AC input and to the DC output. When the DC voltage at the DC output of the hybrid rectifier reaches or exceeds the voltage threshold value, operating the hybrid rectifier in a second operating state in which the thyristor rectifier and the transistor rectifier are each connected to the AC input and to the DC output.

A power converter includes: a converter including four switching elements in full bridge configuration, the converter converting alternating-current power supplied from an alternating-current power supply into direct-current power; a reactor provided between the alternating-current power supply and the converter; a smoothing capacitor connected between direct-current terminals of the converter; an alternating-current voltage detector detecting an alternating-current voltage output from the alternating-current power supply; an alternating current detector detecting a current flowing through the reactor; and a control circuitry controlling a switching operation of the switching elements. The control circuitry controls the switching elements such that a potential fluctuation due to the switching operation is reduced between a P terminal of the converter and an L terminal of the alternating-current power supply, or between a G terminal of the converter and an N terminal of the alternating-current power supply.

An electric power converter includes: an electric power conversion unit configured to convert electric power that has been input, and output the converted electric power; and a control unit configured to control, based on a reference function, an electric power conversion characteristic of the electric power conversion unit, wherein the reference function includes plural droop functions that have been defined according to input values, have drooping characteristics different from one another, and have been connected to each other, and the control unit is configured to control the electric power conversion characteristic by control schemes that are different from one another and are according to the drooping characteristics of the droop functions.