Abstract: A direct current (DC) to DC power converter includes a first converter for converting a first DC bus voltage into a first high frequency AC voltage and a second converter for converting a second high frequency alternating current (AC) voltage into a second DC bus voltage. The DC to DC converter also includes a resonant circuit for coupling the first bus converter and the second bus converter and a controller for providing switching signals to the first converter and the second converter to operate the power converter in a soft switching mode. The resonant circuit includes a high frequency transformer coupled between the first converter and the second converter and an auxiliary converter coupled in series with a first resonant inductor and the high frequency transformer. The resonant circuit further includes second inductor coupled across a first winding of the high frequency transformer. An auxiliary voltage generated by auxiliary converter is added in series with an output voltage of the first converter.

Abstract: A control circuit reduces switching loss by periodically stopping switching elements, and reduces the difference between the time for which positive switching elements are in on state and the time for which negative switching elements are in on state. The control circuit includes a command value signal generator generating command value signals Xu1, Xv1, and Xw1 from line voltage command value signals Xuv, Xvw, and Xwu, and includes a PWM signal generator generating PWM signals by the command value signals Xu1, Xv1, and Xw1. The command value signals Xu1, Xv1, and Xw1 are continuously at “0” for a predetermined period, and are continuously at “2” for another period. This enables reducing the difference between the period for which the PWM signals are low and the period for which they are high.

Abstract: A power supply circuit includes a DC-DC converter and a choke coil. The choke coil includes a pair of coils wound in mutually opposite directions, and the coils are connected between a DC power source and the DC-DC converter. In the choke coil, a self-resonating frequency in a common mode is higher than a self-resonating frequency in a normal mode. In the choke coil, a normal mode impedance at the highest frequency in an AM band is higher than a common mode impedance at the lowest frequency in an FM band.

Abstract: The invention relates to a method for operating a power converter (1), preferably a solar inverter, for feeding a load current (Iload) into a grid (3). The method includes the steps of determining the load current (Iload), monitoring an output voltage (Uout) of the power converter (1), and controlling the load current (Iload), to avoid that the output voltage (Uout) exceeds a voltage limit (Uout,lim), wherein the voltage limit (Uout,lim) is adjusted in dependency of the load current (Iload). Furthermore the invention relates to a corresponding power converter (1) for connecting to a grid (3), preferably it relates to a solar power converter. This power converter (1) includes a load current sensor (142), an output voltage sensor (143) and a load current controller (141).

Abstract: A method and apparatus for providing multi-phase power. In one embodiment, the apparatus comprises a cycloconverter controller for determining a charge ratio based on a reference waveform; and a cycloconverter, coupled to the cycloconverter controller and to a multi-phase AC line, for selectively coupling an alternating current to each line of the multi-phase AC line based on the charge ratio.

Abstract: A switching control circuit of a power converter according to the present invention comprises an input circuit and a clock generator. The input circuit is coupled to receive a feedback signal for generating a switching signal. The clock generator generates a clock signal to determine a switching frequency of the switching signal. The feedback signal is correlated to an output of the power converter. The switching signal is coupled to switch a transformer of the power converter for regulating the output of the power converter. The pulse width of the switching signal is reduced before the switching frequency of the switching signal is changed from a low frequency to a high frequency.

Abstract: A comparator circuit includes a first comparator arranged to compare an input signal with a reference voltage so as to generate a first comparison signal, a second comparator arranged to compare the input signal with a variable reference voltage so as to generate a second comparison signal, a variable reference voltage generator arranged to generate the variable reference voltage, and a logic unit arranged to output one of the first comparison signal and the second comparison signal as a comparison signal. The logic unit outputs the first comparison signal as the comparison signal while controlling the variable reference voltage generator to sweep the variable reference voltage until the first comparison signal and the second comparison signal exhibit desired response behaviors, and moves to a state capable of outputting the second comparison signal as the comparison signal after the sweep of the variable reference voltage is completed.

Abstract: A frequency jittering control circuit includes a frequency jittering circuit, a feedback compensation circuit, a comparator and a control circuit. The frequency jittering circuit generates a frequency jittering signal. The feedback compensation circuit generates a feedback compensation signal in response to the frequency jittering signal and an output signal. The comparator outputs a comparison output signal according to the feedback compensation signal and an oscillation signal. The control circuit outputs a frequency jittering control signal for switching a main switch in a power supply apparatus, according to the comparison output signal, such that the power supply apparatus correspondingly generates the output signal.

Abstract: A hybrid rectifier that works as either a hybrid full bridge or a voltage doubler. Under 220 V AC input condition, the hybrid rectifier operates in full bridge mode, while at 110 V AC input, it operates as voltage doubler rectifier. The hybrid rectifier may be used with a DC-DC converter, such as an LLC resonant converter, in a power supply. With this mode switching, the LLC converter resonant tank design only takes consideration of 220 V AC input case, such that the required operational input voltage range is reduced, and the efficiency of the LLC converter is optimized. Both the size and power loss are reduced by using a single stage structure instead of the conventional two-stage configuration.

Abstract: A converter is provided. The converter includes a first DC/DC converter, a non-isolated DC/DC converter and a control circuit. The first DC/DC converter includes a transformer, a primary side inverter and a secondary side rectifier. The primary side inverter and a secondary side rectifier are operable at multiple operating modes. The control circuit determines an operating mode for the primary side inverter or the secondary side rectifier, and controls the primary side inverter or the secondary side rectifier to change its respective operating mode.

Abstract: Each phase arm of a power conversion device includes at least one converter cell connected in series. For each converter cell, an element driving unit is provided which turns on one switching element in the converter cell as a startup element. The element driving unit is supplied with power from a DC capacitor, and when voltage of the DC capacitor exceeds startup voltage Vsh, turns on the startup element. Thus, at the time of startup of the power conversion device, the DC capacitor in each converter cell is initially charged to desired voltage.

Abstract: An electric power conversion device includes a first arm and a second arm each including converter cells. The converter cell of the first arm is a first converter cell having a full-bridge configuration including an energy storing element and semiconductor switching elements. The converter cell of the second arm is a second converter cell having a half-bridge configuration including an energy storing element and semiconductor switching elements. Thus, short-circuit current between DC terminals is suppressed.

Abstract: A method of controlling a switching regulator includes detecting current-limit events indicating a maximum current threshold has been exceeded. A compensation voltage is adjusted in response to the detected current-limit events, where the compensation voltage defines a duty cycle of the switching regulator. A time is detected for which no current-limit events have been detected and the value of the compensation voltage is adjusted to increase the duty cycle of the switching regulator in response to the detected time exceeding a time step threshold.

Abstract: A system that includes a regulator unit is disclosed. The regulator unit includes first and second phase units whose outputs are coupled to through first and second coupled inductors, respectively, to a power supply node of a circuit block. The first phase unit may be configured to discharge, for a first period of time, the power supply node through the first inductor in response to determining a sense current is greater than a demand current. The operation of the second phase unit may follow that of the first phase unit after a second period of time has elapsed.

Abstract: A power converter circuit includes a transformer. The transformer includes a primary winding and a secondary winding. A primary circuit is coupled to the primary winding. A secondary circuit is coupled to the secondary winding. The primary circuit and the secondary circuit are referenced to different ground voltage potentials that may vary with respect to each other. During operation, the primary circuit controls input of energy to the primary winding of the transformer. The secondary circuit receives the energy through the secondary winding and uses it to produce an output voltage to power a load. The secondary circuit receives and/or generates state information at one of multiple different levels. The secondary circuit controls a flow of current through the secondary winding to convey the state information as feedback to the primary circuit. The primary circuit analyzes a voltage at a node of the primary winding to receive the feedback.

Abstract: The present invention relates to a power conversion device in the power electronics field. An object of the present invention is to provide a technique of determining whether a switching element operates normally or not from a gate monitor signal of a power conversion device, and predicting a sign of a failure by obtaining the temperature of the switching element from a transient state of the switching voltage of the power conversion circuit as a component of the power conversion device without using a new signal path.

Abstract: An inverter device comprises a first stage circuit, a second stage circuit and a control module. The first stage circuit comprises a first switch module and a charge-discharge module. The second stage circuit comprises a second switch module and a filter module. The control module outputs a first control signal for controlling the first switch module to turn on/off and a second control signal for controlling the second switch module to turn on/off. The control module obtains an input current from the first stage circuit, and adjusts the input current according to a predetermined current value. In addition, the control module obtains an output power from the AC output terminal, and adjusts the duty cycle of the first control signal according to the output power and a predetermined output power.

Abstract: A method comprises connecting a first resonant converter and a second resonant converter in parallel, detecting a first signal indicating a first soft switching process of the first resonant converter and a second signal indicating a second soft switching process of the second resonant converter and adjusting a first switching frequency of the first resonant converter by a first control circuit and a second switching frequency of the second resonant converter by a second control circuit until a load current flowing through the first resonant converter is substantially equal to a load current flowing through the second resonant converter.

Abstract: A converter includes: a first transistor (Q1) connected between a first output terminal (T1) and an input terminal (T0); a second transistor (Q2) connected between the input terminal (T0) and a second output terminal (T2); first and second diodes (D1, D2) connected in anti-parallel to the first and second transistors (Q1, Q2), respectively; and a bidirectional switch that is connected between the input terminal (T0) and a third output terminal (T3) and that includes third and fourth transistors (Q3, Q4) and third and fourth diodes (D3, D4). The first and second diodes (D1, D2) and the third and fourth transistors (Q3, Q4) each are formed of a wide band gap semiconductor. The third and fourth diodes (D3, D4) and the first and second transistors (Q1, Q2) each are formed of a semiconductor other than the wide band gap semiconductor.

Abstract: One direct current to direct current converter disclosed herein can implement three control modes: a predefined control mode in which an outer phase-shift angle is determined based on a predefined process, a current control mode in which the outer phase-shift angle is determined based on a predefined reference current profile and a DC current output, and a voltage-current control mode in which a reference current value is determined using a reference voltage value and a DC voltage output. The soft starting process can start from the predefined control mode and later switch to the current control mode followed by the voltage-current control mode or directly switch to the voltage-current control mode. The soft starting process can also start from the current control mode and later switch to the voltage-current control mode.