A switched current source circuit, comprising first and second voltage source nodes; a load; a current source; and capacitor switching circuitry comprising a load node, a capacitor and a plurality of switches configured, based on a control signal, to adopt a biasing configuration followed by an active configuration, wherein in the biasing configuration, the load node is conductively connected to the second voltage source node to bias a voltage level at the load node, and the capacitor is connected so that it at least partly charges; and in the active configuration, the load node is conductively connected via the load to the first voltage source node, and via the capacitor to the current source to increase a potential difference between the first voltage source node and the load node.

There is provided a fuel cell system. This fuel cell system comprises a fuel cell configured to generate electric power using reactive gases; a voltage sensor configured to measure a voltage output from the fuel cell; a converter configured to boost an input voltage that is input from the fuel cell; and a controller configured to control the converter. In the case where the voltage output from the fuel cell to the converter is to be boosted after a changeover of an operating state of the fuel cell system from an intermittent operation to an ordinary operation, when a duty ratio D1 calculated by Mathematical Formula I is greater than a duty ratio D2 calculated by Mathematical Formula II, the controller causes the converter to boost the voltage output from the fuel cell at the duty ratio D2.

[00001]$\begin{array}{cc}\left[\mathrm{Math}..Math.1\right].Math.& \\ D.Math..Math.1=1-\frac{\mathrm{Vltrg}}{\mathrm{VH}}& \left(I\right)\end{array}$

where VH (V) denotes a value of output voltage that is output from the converter, and Vltrg (V) denotes an estimated value of voltage that is output from the fuel cell,

[00002]$\begin{array}{cc}\left[\mathrm{Math}..Math.2\right].Math.& \\ D.Math..Math.2=1-\frac{\left(\mathrm{Vl}+\mathrm{Vlmrg}\right)}{\mathrm{Vhul}}& \left(\mathrm{II}\right)\end{array}$

where Vl (V) denotes a measured value of voltage of the fuel cell by the voltage sensor, Vlmrg (V) denotes a cor

A chopped current input electrical energy converter includes at least one conversion module (K1, K2) generating at least one first output signal (V.sub.out1) and one second output signal (V.sub.out2) and including: a transformer (10), an input switching stage (20) controlling the transfer of electrical energy to the transformer (10), and at least one first output stage (30) and one second output stage (40), the first output stage (30) generating the first output signal (V.sub.out1), and the second output stage (40) generating the second output signal (V.sub.out2); the level of the first output signal (V.sub.out1) reflected at a primary winding (11) of the transformer (10) is greater than the level of the second output signal (V.sub.out2) reflected at the primary winding (11) of the transformer (10).

Disclosed is a method and apparatus. The method includes detecting an operating state of a current source converter that comprises a current source rectifier (1), a current source inverter (2), and an inductor circuit (3) connected between an output (p, n) of the current source rectifier (1) and an input (q, r) of the current source inverter (2); and dependent on the detected operating state, operating the current source converter in a first operating mode or a second operating mode. Operating the current source converter in the first operating mode comprises operating the current source rectifier (1) in a 2/3 mode and operating the current source inverter in a 3/3 mode, and operating the current source converter in the second operating mode comprises operating the current source inverter (2) in the 2/3 mode and operating the current source rectifier in the 3/3 mode.

In one embodiment, a circuit comprises a charge pump. A gain control circuit is configured to detect an input voltage and generate a gain control signal to change a gain of the charge pump to maintain the output voltage of the charge pump in a voltage range. A voltage to frequency converter is configured to detect the input voltage and change a frequency of a frequency control signal applied to the charge pump based in the detected input voltage to maintain the frequency in a frequency range so that the output voltage of the charge pump is maintained in the voltage range.

System and method for detecting a power. For example, a system for detecting a power includes: a first signal converter configured to receive a first signal and generate a pulse-width-modulation signal based at least in part on the first signal; a second signal converter configured to receive a second signal and generate a voltage signal based at least in part on the second signal; and a low-pass filter configured to receive the pulse-width-modulation signal and the voltage signal and generate a power detection signal based at least in part on the pulse-width-modulation signal and the voltage signal; wherein: the first signal is either an input current or an input voltage; the second signal is either the input current or the input voltage; and the first signal and the second signal are different.

A controller for a power converter, a corresponding power converter and a corresponding method are provided. The controller for a power converter includes a rectifier configured to receive an alternating current input signal and output rectified half waves, an output capacitor and a current control device is coupled between the rectifier and the output capacitor. After reaching a first maximum voltage, power flowing is gradually reduced, and later the current provided to the output capacitor is gradually ramped up.

A power receiving device performs a power supply control including repeatedly performing: first rectification mode in which in response to detection of an energization of a first bridge circuit, a first high-side and a second low-side switches are turned on and a first low-side and a second high-side switches are turned off; and second rectification mode in which in response to detection of an energization of a second bridge circuit, the first low-side and the second high-side switches are turned on and the first high-side and the second low-side switches are turned off, and a power adjustment control including: first commutation mode in which the first high-side switch is turned off and the first low-side switch is turned on during the first rectification mode; and second commutation mode in which the second high-side switch is turned off and the second low-side switch is turned on during the second rectification mode.

System and method for detecting a power. For example, a system for detecting a power includes: a first signal converter configured to receive a first signal and generate a pulse-width-modulation signal based at least in part on the first signal; a second signal converter configured to receive a second signal and generate a voltage signal based at least in part on the second signal; and a low-pass filter configured to receive the pulse-width-modulation signal and the voltage signal and generate a power detection signal based at least in part on the pulse-width-modulation signal and the voltage signal; wherein: the first signal is either an input current or an input voltage; the second signal is either the input current or the input voltage; and the first signal and the second signal are different.

A circuit arrangement for a current converter has a half bridge with two series-connected power semiconductor switches in each case. The half bridge has a module with a power semiconductor switch in each case, a first DC voltage terminal, a second DC voltage terminal and an AC voltage terminal. A capacitor is connected in parallel with the half bridge and has a first and second capacitor terminals. A first busbar connects the first DC voltage terminal to the first capacitor terminal, and a second busbar connects the second DC voltage terminal to the second capacitor terminal. The first and the second busbars are arranged as to be spatially parallel and electrically insulated from each other. The circuit arrangement has a resistor connected in series with the capacitor, wherein the resistor is arranged in the first and/or second busbar.