Abstract: A switching branch for a three-level inverter, comprising a first and second switch (S1, S2) in series between a positive DC pole (P) and an AC pole (AC), a first and second diode (D1, D2) parallel to the first and second switches, a third and fourth switch (S3, S4) in series between a negative DC pole (N) and the AC pole, a third and fourth diode (D3, D4) parallel to the third and fourth switches, a fifth diode (D5) between a neutral DC pole (M) and a point between the first and second switches, a sixth diode (D6) between the neutral DC pole and a point between the third and fourth switches, a fifth switch (S5) and a seventh diode (D7) in series between the neutral DC and AC poles, and a sixth switch (S6) and an eighth diode (D8) in series between the neutral DC and AC poles.

Abstract: A soft-start circuit for a switching regulator (e.g., a buck converter) in which the soft-start circuit supplies a DC ramp voltage to the switch regulator's pre-driver such that the pulsed gate voltage supplied to power switch during the initial soft-start operating phase includes a series of pulses having amplitudes that respectively gradually change (e.g., sequentially increase from 0V to the system operating voltage), whereby the regulated output voltage passed from the power switch to the load is gradually increased at a rate that prevents voltage overshoot and inrush current. The DC ramp voltage is generated, for example, by a current source that begins charging a capacitor at the beginning of the initial soft-start operating phase. This arrangement allows a constant-frequency ramp signal generated by a single oscillator to be shared by multiple switch regulators that are fabricated on an IC chip.

Abstract: A power supply system includes: a switching power supply; a control device; an auxiliary power supply circuit, which is connected in parallel with the switching power supply with respect to an AC power supply, which includes an electricity storage unit for storing electricity by charging current fed from the alternating current power supply, and which feeds power to the control device; and a first switching unit for switching a connection state of the auxiliary power supply circuit to the alternating current power supply. The control device is configured to, upon starting up the switching power supply, switch the first switching unit into a state where the auxiliary power supply circuit is separated from the alternating current power supply.

Abstract: Disclosed are an isolated power converter and a switching control signal using the same. In the isolated power converter, the positions of the power switch and the primary winding are exchanged, and the feedback voltage detection and secondary current zero-crossing detection are carried out in accordance with the voltage across the primary winding. Thus, primary side control can still be implemented without employment of an auxiliary winding.

Abstract: The disclosure relates to a voltage generator for providing an output voltage in accordance with a received target signal, the voltage generator comprising: a resonant converter configured to receive an input voltage, the resonant converter comprising: a first switch; a second switch connected in series with the first switch between the input voltage and ground (GND); a resonant tank associated with the second switch; an output capacitor coupled to the resonant tank and configured to provide an output voltage; and a rectifier configured to allow charge to flow in a single direction between the resonant tank and the output capacitor; and a controller configured to receive the target signal and to set an operating parameter of the resonant converter in accordance with a difference between an output value which is related to the output voltage and the target signal.

Abstract: A power supply apparatus includes a power supply section and a control section. The power supply section includes a first switch which performs switching of power-supply output, an inductor and a capacitor which form an LC circuit that resonates current flowing through the first switch, and a second switch which changes capacitance of the capacitor. The control section finds in advance a correspondence between a time ratio of a switching pulse of the first switch and a resonance frequency which matches an edge of a switching pulse having each time ratio, and controls switching of the second switch so as to resonate the LC circuit at a resonance frequency corresponding to a time ratio at operation time.

Abstract: A switch controller for a variable output voltage power converter includes a pulse width modulator (PWM) output producing a pulsed signal for driving a power converter switch. A mode selector output is connected to a multiplier. A period selector output is connected to the multiplier and to a PWM input. The multiplier output is connected to another PWM input. A comparator output is connected to a period selector input. The period selector outputs a nominal cycle time to the PWM when an operating on-time state is greater than a minimum operating on-time. The period selector outputs an updated cycle time greater than the nominal cycle time when the operating on-time state is less than the minimum operating on-time causing the PWM to output a pulsed signal with the updated cycle time and a duty cycle equal to a duty cycle of an immediately preceding pulsed signal.

Abstract: There is provided a device in which superimposition of noise radiated from a circuit is reduced, and a noise reducing effect of a filter is ensured. A DC-DC converter according to the present invention includes a transformer, a high voltage-side switching circuit section, a low voltage-side switching circuit section, a noise filter circuit section electrically disposed between the low voltage-side switching circuit section and the low voltage-side circuit section, a metallic case that houses the transformer, the high voltage-side switching circuit section, the low voltage-side switching circuit section, and the noise filter circuit section, a drive circuit board having a drive circuit that drives the low voltage-side switching circuit section, and a metallic base board having the drive circuit board mounted thereon. The case has a metallic partition wall connected to the case. The partition wall is disposed between the low voltage-side switching circuit section and the noise filter circuit section.

Abstract: An object is to suppress deterioration of a high-voltage side battery regardless of the magnitude of a load current. Provided is a control device of a DC-DC converter that is constituted by a primary side circuit that is electrically connected between an input side and a transformer, and a secondary side circuit that is electrically connected between an output side and the transformer. The control device includes a command generating unit 325 that sets an output current limiting value to a predetermined value on the basis of a detected input voltage, a duty generating unit 330 that calculates a duty configured to turn ON/OFF a switching element on the basis of the output current limiting value and a detected output current, and a switching signal generating unit 335 that generates a switching signal on the basis of the duty. The duty generating unit 330 generates the duty so that an output current is limited to the output current limiting value or less.

Abstract: A switched mode power supply (SMPS) comprising a controller configured to control switching of the SMPS to regulate an output voltage at an output of the SMPS based on a feedback signal that indicates the output voltage, and a voltage droop control circuit. The voltage droop control circuit comprises a voltage droop control signal generator that detects a voltage drop across a component of the SMPS that is indicative of a current flowing through the output of the SMPS during operation. The voltage droop control signal generator is an active device arranged to generate, based on the detected voltage drop, an output voltage droop control signal for causing the controller to adjust the regulation of the output voltage. The voltage droop control circuit further comprises a reference voltage generator arranged to bias at least one of the first and second inputs of the voltage droop control signal generator.

Abstract: A converter circuit with short-circuit protection can include a plurality of phase legs having a series connection of normally-on switches, between voltage rails of a DC voltage link, a DC link capacitor, and AC voltage connection points between the normally-on switches. A phase-to-phase short-circuit protection circuit includes a parallel connection of a resistive component and a controllable switch. The phase-to-phase short-circuit protection circuit including a first terminal connected to an AC voltage connection point and a second terminal forms an input or an output of the converter circuit; and a controllable switch is connected in series with the DC link capacitor. Upon lack of control of the normally-on switches the controllable switch of the at least one phase-to-phase short-circuit protection circuit and the controllable switch of the phase leg short-circuit protection circuit are adapted to be controlled to a non-conductive state.

Abstract: A control circuit with deep burst mode for power converter according to the present invention comprises a load detection circuit and a PWM circuit. The load detection circuit generates a switching control signal in response to a feedback signal. The feedback signal is correlated to a load condition of the power converter. The PWM circuit generates a switching signal to regulate an output of the power converter in response to the switching control signal and the feedback signal. The control circuit performs a deep burst mode to switch the switching signal only one time during each deep burst period when the load condition of the power converter is a very light-load. Therefore, switching loss is reduced so that the power consumption of the power converter is also reduced.

Abstract: This disclosure relates to radio frequency (RF) power converters and methods of operating the same. In one embodiment, an RF power converter includes an RF switching converter, a low-drop out (LDO) regulation circuit, and an RF filter. The RF filter is coupled to receive a pulsed output voltage from the RF switching converter and a supply voltage from the LDO regulation circuit. The RF filter is operable to alternate between a first RF filter topology and a second RF filter topology. In the first RF filter topology, the RF filter is configured to convert the pulsed output voltage from a switching circuit into the supply voltage. The RF filter in the second RF filter topology is configured to filter the supply voltage from the LDO regulation circuit to reduce a ripple variation in a supply voltage level of the supply voltage. As such, the RF filter provides greater versatility.

Abstract: A power conversion apparatus, including a transformer, a switch, an analog controller, a digital controller, and a voltage converter-based feedback circuit, is provided. The primary side of the transformer is coupled to an input voltage, and the secondary side of the transformer is coupled to an output voltage provided to a load. The switch intermittently transmits the input voltage to the primary side of the transformer. The analog controller is disposed at one of the primary side and the secondary side of the transformer and configured to control the operation of the switch in response to an analog feedback signal. The digital controller is disposed at the other one of the primary side and the secondary side and configured to generate a digital feedback signal. The voltage converter-based feedback circuit is configured to convert the digital feedback signal to the analog feedback signal based on a voltage conversion characteristic thereof.

Abstract: A circuit for a hybrid voltage source converter suitable for high voltage DC power transmission and reactive power compensation. The circuit comprises an assembly of electrically interconnected elements (Elements 1 to 20) including a plurality of first elements (Elements 1 to 6) and a plurality of second elements (Elements 7 to 20). Each of the first and second elements is configurable to be bypassed, to be disconnected or to include a circuit arrangement of one or more electronic components to construct, in use, a hybrid voltage source converter including at least one first element and at least one second element and in which the circuit arrangement included in the or each first element is different to the circuit arrangement included in the or each second element.

Abstract: System and method for regulating a power converter. The system includes a first signal processing component configured to receive at least a sensed signal and generate a first signal. The sensed signal is associated with a primary current flowing through a primary winding coupled to a secondary winding for a power converter. Additionally, the system includes a second signal processing component configured to generate a second signal, an integrator component configured to receive the first signal and the second signal and generate a third signal, and a comparator configured to process information associated with the third signal and the sensed signal and generate a comparison signal based on at least information associated with the third signal and the sensed signal.

Abstract: A switching power-supply device includes: a first series circuit including a first switching element; and a second switching element, a second series circuit including a third switching element and a fourth switching element; and a control unit that, while making frequencies of switching signals of the first series circuit and the second series circuit be the same, performs control of turning on-and-off the first switching element and the second switching element, alternately, with dead time at which the first switching element and the second switching element become off and turning on-and-off the third switching element and the fourth switching element, alternately, with dead time at which the third switching element and the fourth switching element become off, wherein the control unit controls a phase difference between the switching signal of the first series circuit and the switching signal of the second series circuit.

Abstract: An AC-to-DC converter involves a rectifier, an inductor, a storage capacitor, a switch, and a microcontroller. In a capacitor pre-charge operation, the periodicity and voltage amplitude of an AC supply voltage are determined. Based on this, the microcontroller identifies one of a plurality of stored sequences. Each sequence is a list of values. The microcontroller turns off the switch on AC supply voltage zero crossings and turns on the switch in accordance with the values. As a result, a sequence of identical pulses of charging current flows into the storage capacitor. Each pulse passes in a current path from the rectifier, through the inductor, through the capacitor, through the switch, and back to the rectifier. During the pre-charge operation, the microcontroller does not measure the capacitor voltage and use that to calculate when to the turn the switch on next, but rather the sequence of precalculated stored values is used.

Abstract: A sampling circuit of the power converter according to the present invention comprises an amplifier circuit receiving a reflected voltage for generating a first signal. A first switch and a first capacitor are utilized to generate a second signal in response to the reflected voltage. A sample-signal circuit generates a sample signal in response to a falling edge of a switching signal. The switching signal is generated in accordance with a feedback signal for regulating an output of the power converter. The feedback signal is generated in accordance with the second signal. The sample signal is utilized to control the first switch for sampling the reflected voltage. The sample signal is disabled once the first signal is lower than the second signal. The sampling circuit precisely samples the reflected voltage of the transformer of the power converter for regulating the output of the power converter.

Abstract: System and method for protecting a power conversion system. An example system controller includes a protection component and a driving component. The protection component is configured to receive a feedback signal, a reference signal, and a demagnetization signal generated based on at least information associated with the feedback signal, process information associated with the feedback signal, the reference signal, and the demagnetization signal, and generate a protection signal based on at least information associated with the feedback signal, the reference signal, and the demagnetization signal. The demagnetization signal is related to multiple demagnetization periods of the power conversion system, the multiple demagnetization periods including a first demagnetization period and a second demagnetization period.