Abstract: A method for reducing electromagnetic interference in a flyback converter includes activating a first switch to generate a primary current therein. The first switch is deactivated to generate a secondary current from a magnetic flux generated by the primary current. The magnetic flux is removed by the generation of the secondary current. A second switch is activated with a first voltage pulse to limit an excess voltage across the first switch. The excess voltage is generated in response to the deactivation of the first switch. A second switch is activated with a second voltage pulse to limit a voltage oscillation across the first switch. The voltage oscillation occurs after the removal of the magnetic flux. A first pulse width of the first voltage pulse is increased by a first jitter delay. A second pulse width of the second voltage pulse is increased by a second jitter delay.

Abstract: In a control apparatus for a power conversion apparatus, a spectrum changing unit changes a spectrum of at least one of bus harmonic components and switch harmonic components so as to meet at least one of a separation condition and a reduction condition. The bus harmonic components are harmonic components superimposed on a voltage of the bus in accompaniment with on-off operations of switches configuring at least one power conversion apparatuses. The switch harmonic components are harmonic components included in a switching pattern of switches configuring the remaining at least one power conversion apparatus. The separation condition is that the frequencies of both harmonic components are separated by a predetermined value or more. The reduction condition is that an amplitude of at least one harmonic component is reduced when the difference between the frequencies of both harmonic components is less than the predetermined value.

Abstract: The present invention relates to an inverter device for a microgrid, and a method for controlling the same, the inverter device including: a waveform detector detecting a voltage waveform and a current waveform applied to a load; a control unit determining whether a sine wave appears based on the detected voltage waveform and the detected current waveform and performing voltage control or low order harmonic compensation depending on a determination result; and a switch generating a voltage waveform in a form of the sine wave by being turned on/off depending on a control signal received from the control unit and supplying the generated voltage waveform in the form of the sine wave to the load.

Abstract: System and method for protecting a power converter. An example system controller for protecting a power converter includes a signal generator, a comparator, and a modulation and drive component. The signal generator is configured to generate a threshold signal. The comparator is configured to receive the threshold signal and a current sensing signal and generate a comparison signal based on at least information associated with the threshold signal and the current sensing signal, the current sensing signal indicating a magnitude of a primary current flowing through a primary winding of a power converter. The modulation and drive component is coupled to the signal generator.

Abstract: The power supply apparatus includes a detecting unit that has a first detecting device, a second detecting device and a third detecting device, detects a current flowing into the primary winding, and outputs a voltage corresponding to the current, and a control unit that controls a switching operation of the switching element, an output voltage which the detecting unit outputs to the control unit includes a first output voltage at which the control unit stops an operation of the switching element at a time of the second state, a second output voltage at which the control unit stops the operation of the switching element at a time of the first state, a third output voltage at which the second detecting device is brought into a conducting state, and a fourth output voltage at which the third detecting device is brought into a conducting state.

Abstract: An embodiment of a resonant converter includes having resonant circuitry having inductive and capacitive elements configured to create electrical resonance when an input voltage is applied and a synchronous rectifier coupled between at least a portion of the resonant circuitry and an output of the resonant converter. The synchronous rectifier includes a diode, and an electrical switch. Control circuitry is configured to operate the electrical switch such that the electrical switch is turned on when there is substantially no voltage across the diode and current flow in the diode is positive in a direction from anode to cathode.

Abstract: A method for controlling a DC-DC converter including an energy accumulation element, an energy storage element and a switching element, said control method including the following steps implemented by a control unit: a step of generating a control signal for the switching element with a duty cycle ? that is a function of information relating to the output electrical conditions of said converter; a step of controlling said switching element by means of said control signal; a step of compensating said control signal for a continuous conduction mode; a step of compensating said control signal for a discontinuous conduction mode; and a step of estimating the current operating mode of said converter in order to control the implementation either of the compensation step or of the compensation step as a function of the estimated current operating mode. The invention further relates to a DC-DC converter for implementing said control method.

Abstract: A controller controls power between a source and a load with a link capacitor. (a) A switch vector is selected based on load and source values, a capacitor voltage value, and a switch state selection mode. The switch vector identifies an on or off configuration for load and source switches during a subcycle that allow or do not allow current flow between the link capacitor and the load switch or source switch. (b) The state of the load and source switches is controlled in the on configuration or in the off configuration based on the selected switch vector. (c) It is determined that it is time to select a next switch vector. (a) to (c) are repeated for each subcycle of the determined number of switching subcycles. At least one load switch and at least one source switch are simultaneously in the on configuration during at least one subcycle.

Abstract: System and method for protecting a power converter. An example system controller for protecting a power converter includes a signal generator, a comparator, and a modulation and drive component. The signal generator is configured to generate a threshold signal. The comparator is configured to receive the threshold signal and a current sensing signal and generate a comparison signal based on at least information associated with the threshold signal and the current sensing signal, the current sensing signal indicating a magnitude of a primary current flowing through a primary winding of a power converter. The modulation and drive component is coupled to the signal generator.

Abstract: An isolated switching power converter is provided wherein a secondary side is valley mode switched to transmit data to a primary side. This provides secondary side regulation without the need for an optocoupler. Data communication between the primary and secondary sides of switching power converters is presented.

Abstract: A direct current to direct current converter includes a first voltage converting circuit which converts an input voltage into a first power supply voltage, a control block which stores information about voltage levels of a second power supply voltage, receives an external control signal, and generates a voltage level selection signal indicating a first one of the voltage levels, a second voltage converting circuit which converts the input voltage into the second power supply voltage having the first one indicated by the voltage level selection signal, and an abnormal state detector which detects an abnormal state of a display panel, and provides a current limit signal to the control block when the abnormal state is detected. In response to the current limit signal, the control block generates the voltage level selection signal indicating a second one of the voltage levels regardless of the external control signal.

Abstract: A grid connection power conversion device is provided in which an amplitude of an output voltage from an inverter is increased stepwise from 0, after start-up of the power conversion device, to adjust the amplitude of the output voltage from the inverter to match an amplitude of a commercial system voltage as detected, and thereafter the inverter is connected to the commercial power system to start grid-connected operation. This makes it possible to prevent the voltage applied to a capacitor provided between the inverter and the commercial power system from abruptly increasing from 0V to the commercial system voltage at the start-up of the power conversion device, thereby making it possible to reduce an inrush current to the capacitor at the start-up without using an inrush current prevention circuitry.

Abstract: A method for controlling a DC-to-DC converter includes: (a) regulating a magnitude of an output voltage of the DC-to-DC converter according to a magnitude of a reference voltage; (b) in response to a command to enter the unregulated operating mode, allowing the magnitude of the output voltage to fall; and (c) adjusting the magnitude of the reference voltage to track the magnitude of the output voltage. A controller for a DC-to-DC converter includes reference and switching modules. The reference module generates a reference voltage, such that: (a) a magnitude of the reference voltage is fixed, in a regulated operating mode, and (b) the magnitude of the reference voltage tracks a magnitude of an output voltage of the DC-to-DC converter, in the unregulated operating mode. The switching module controls a power stage of the DC-to-DC converter to regulate the magnitude of the output voltage, in the regulated operating mode.

Abstract: In this invention we introduce the concept of a fundamental switching cell with complimentary switchers s and a controlled dead time which is one of the embodiments of this invention. This fundamental switching cell can be used in isolated DC-DC Converter applications and also used for totem pole bridgeless power factor correction applications. One of the main embodiments of this invention describes a circuit wherein such a fundamental switching cell is used to transfer the power across a transformer towards secondary while providing power factor correction for the input line current while extracting the energy from the line and steering the low frequency ripple of the input current towards the bulk capacitor and regulating the voltage in the secondary of the transformer.

Abstract: A semiconductor device includes a voltage hold circuit that raises a second boosted voltage with rise of an output voltage of a booster circuit that generates a first boosted voltage and then maintains the second boosted voltage at a point when the output voltage reaches a hold voltage level after that, and a first switch that short-circuits a first output terminal through which the first boosted voltage is output and a second output terminal through which the second boosted voltage is output until the output voltage reaches the hold voltage level.

Abstract: Disclosed are AC-DC voltage converter circuits and methods for low standby power consumption. In one embodiment, a method can include: (i) detecting operating states of an input power supply, where the input power supply is received by a safety capacitor and provided to a switching power supply circuit after being rectified and filtered; (ii) removing a phantom load when the input power supply operates in a normal operating state; (iii) loading the phantom load when the input power supply operates in an under voltage lock out state; and (iv) when the input power supply operates in the under voltage lock out state, using energy stored in the safety capacitor to supply power to a load of the switching power supply circuit and the phantom load, and disabling a power stage circuit until a voltage of the safety capacitor is reduced to less than a safety threshold value.

Abstract: A signal transmission circuit transmitting abnormality signals from a primary side circuit to a secondary side circuit is provided, in which the primary side circuit includes switching elements driven by drive circuits, the secondary circuit including a receiving unit receiving the abnormality signals transmitted from the primary side circuit. The signal transmission circuit includes: a plurality of isolation elements that electrically isolate the primary side circuit and the secondary side circuit, and allows the abnormality signals to be transmitted therethrough; and a logic circuit that receives the abnormality signals from the isolation elements, outputting a predetermined signal indicating an occurrence of an abnormality when at least one of the switching elements shows the abnormality.

Abstract: An AC capable power amplifier arrangement is realized that includes a buck converter with a power inductor, two buck switches, and alternately a buck-boost converter using four switches, each driving an output polarity steering set of four switches. The polarity steering switches convey the converter output current to output terminals that connect to a load with a capacitor connected in parallel. A differential receiver is connected to the output terminals to provide negative feedback. A mixer receives an input voltage signal, an output of the differential receiver, and output from a triangle wave generator. A set of two comparators for buck amplifier conversion, or four comparators for buck-boost amplifier conversion, each receives an output of the mixer. Each of the comparators produces a respective output for driving the converter switches through simple steering logic interfaces between the comparators, the converter components and a polarity steering output stage.

Abstract: A method and corresponding system for operating an inverter includes setting an input voltage (UPV) of the inverter by an input-side DC-DC converter and/or an output-side inverter bridge, wherein the input voltage (UPV) corresponds to an MPP voltage (UMPP) at which a generator connectable on the input side outputs a maximum electrical power, and determining a first temperature value (TDCDC) in the DC-DC converter and a second temperature value (TDCAC) in the inverter bridge.

Abstract: An auto-calibrated current sensing comparator is provided. A secondary dynamic comparator shares the same inputs and acts to adjust a calibration control of the current sensing comparator. The calibration control may be in the form of adjusting the offset of the current sensing comparator or adjusting a propagation delay that is added to its output.