In this DC/DC converter, a first controller calculates a first operation value on the basis of a difference between output voltage Vout and a first calculated value calculated on the basis of a detection value of voltage of the charge/discharge capacitor. A second controller calculates a second operation value on the basis of a difference between a charge/discharge capacitor voltage target value Vcf* and charge/discharge capacitor voltage Vcf. In control blocks, addition and subtraction of the first and second operation values are performed, and the conduction rates for switching elements are controlled, to control the output voltage and a charge/discharge capacitor voltage, thereby preventing application of overvoltage to the switching elements.

A voltage balance control device and a voltage balance control method for a flying-capacitor multilevel converter are provided. A current direction forecasting unit acquires a voltage change amount of any selected flying capacitor of the flying-capacitor multilevel converter, and receives a feedback signal of two adjacent switch elements corresponding to the selected flying capacitor. A computing result is generated according to an average value or a cumulative value of the feedback signal in the adjusting period. After multiplication and/or division is performed on the voltage change amount and the computing result, the current direction can be forecasted according to the obtained sign. Consequently, the voltage balance of the flying capacitor of the flying-capacitor multilevel converter can be achieved.

A circuit includes first and second transistors, a capacitor, and a controller. The controller is coupled to the control inputs of the first and second transistors. The controller configured to, during a first mode and in accordance with a first time-varying duty cycle, turn on and off the first transistor while turning on the second transistor when the first transistor is off. The controller is also configured to, during a second mode following the first mode, and in accordance with a second time-varying duty cycle, turn on and off the first transistor while turning on the second transistor when the first transistor is off.

A power supply has a multi-level DC-DC converter and a battery pack with two or more cells provided in series. The switching DC-DC converter provides a regulated voltage at an output. The converter has an energy storage element. The switching regulator is designed to selectively operate in two or more different modes. It switches between a first mode where one cell is connected (between battery and inductor of the converter), and the converter functions like a single cell buck converter and a second mode where two cells are connected in series and the converter functions like a two series cell buck converter. In general, any number of cells and modes can be provided, with successive cells being connected in series in each mode.

A circuit including: a control system for a three-level buck converter, the three-level buck converter including multiple input switches, each of the input switches receiving one of a plurality of different pulse width modulated signals, the control system including: a first clock signal and a second clock signal, the second clock signal being a phase-shifted version of the first clock signal; ramp generating circuitry receiving the first and second clock signals and producing first and second ramp signals, respectively, from the first and second clock signals; a first comparing circuit receiving the first ramp signal and producing a first one of the pulse width modulated signals therefrom; and a second comparing circuit receiving the second ramp signal and producing a second one of the pulse width modulated signals therefrom.

A multilevel converter comprising a first switching branch connected between a positive DC-link terminal and an AC output terminal and comprising series-connected first and second switching elements, a second switching branch connected between the AC output terminal and a negative DC-link terminal and comprising series-connected third and fourth switching elements, a third switching branch connected between a DC-link neutral point and a connection point of the first and the second switching elements, a fourth switching branch connected between the DC-link neutral point and a connection point of the third and the fourth switching elements, the fourth switching branch being completely independent from the third switching branch, and a flying capacitor connected between the connection point of the first and the second switching elements and the connection point of the third and the fourth switching elements.

One example includes a half-bridge switching circuit system. The system includes a first plurality of switches arranged between a first rail voltage and an output on which an output voltage is provided and a second plurality of switches arranged between a second rail voltage and the output, the first and second pluralities of switches being controlled via a plurality of switching signals. The system also includes a plurality of flying capacitors arranged to interconnect the first and second pluralities of switches, and further includes a plurality of snubber circuits that are each arranged in parallel with a respective one of the plurality of flying capacitors, the first plurality of switches, and the second plurality of switches.

A power converter, includes a first terminal and a second terminal which are connected to a direct current; a third terminal connected to an alternating current; N multi-level bridge arms connected in parallel to the first terminal and the second terminal, where the N multi-level bridge arms work in a parallel-interleaved manner, each multi-level bridge arm of the N multi-level bridge arms includes an alternating current node, and multiple time-varying levels are generated at the alternating current node, where the multiple levels are more than two levels; and a coupling inductor, including N windings coupled by one common magnetic core, where one end of each winding of the N windings is connected to an alternating current node of one multi-level bridge arm of the N multi-level bridge arms, and the other end of each winding of the N windings is connected to the third terminal.

The present invention relates to a multiple output boost DC-DC power converter generating two, three or more separate DC output voltages, and to a multi-level power inverter and an alternating current generator both employing the multiple output boost DC-DC power converter.

An intermediate voltage circuit current converter having two current converter sections arranged in series on the direct voltage side is disclosed. The current converter section has a capacitor connected in parallel with two bridge modules that are connected in series with each other. The output of the current converter section is located on the series connection between the two bridge modules and the outputs of the two current converter sections are connected to a further bridge module. Each bridge modules comprises a series connection of two power semiconductor units. The intermediate potentials on the connection between the two power semiconductor units in each of the bridge modules are electrically connected to one another by a further capacitor, and the intermediate potential of the further bridge module provides the phase connection of the intermediate voltage circuit current converter for a given phase of the intermediate voltage circuit current converter.