Abstract: A power converter is provided. The power converter includes at least one leg. The at least one leg of the power converter includes a plurality of switching units. The switching units are coupled with each other in a serial fashion. Further, in the power converter, the switching units are selected such that at least two switching units in the power converter have different operating voltages.

Abstract: The present invention is a system, apparatus and method of a PFC rectifier having a programmable output voltage that does not incur a drastic penalty in the overall size or volume of the device, or a significant degradation in efficiency. The PFC rectifier of the present invention may incorporate a two-stage solution for output voltage regulation. The present invention provides a topology of a small-size/volume PFC rectifier with a variable (i.e. programmable) output voltage and a complementary control method. The two-stage system of the present invention incorporates a smaller and lower cost capacitor than the bulky size and costly energy storage capacitors required in conventional prior art. The present invention also achieves tight output regulation. The two-stage topology of the present invention further achieves on-line efficiency optimization and significantly reduces the volume of the downstream stage over the prior art examples through dynamic adjustment of the downstream stage supply voltage.

Abstract: Embodiments disclosed herein describe the use of two inductors in a non-isolated power converter. The power converter receives power from a non-regulated power source, and converts the received power to regulated output signals. Each inductor in the power converter receives power provided from the non-regulated power source via a switch controlled by a controller, and provides a regulated output to a power converter load. A first regulated output provided by a first inductor can be representative of a second regulated output provided by a second inductor. In addition, a voltage feedback signal can be provided for use by the controller based on the first regulated output and/or the second regulated output.

Abstract: We describe a photovoltaic power conditioning unit comprising: both dc and ac power inputs; a dc link; at least one dc-to-dc converter coupled between dc input and dc link; and a dc-to-ac converter coupled between dc link and ac output. The dc-to-dc converter comprises: a transformer having input and output windings; an input dc-to-ac converter coupled between dc input and input winding; and an ac-to-dc converter coupled between output winding the dc link. The output winding has a winding tap between the first and second portions. The ac-to-dc converter comprises: first and second rectifiers, each connected to a respective first and second portion of the output winding, to the dc link and winding tap; and a series inductor connected to the winding tap. Rectifiers are connected to the winding tap of the output winding via the series inductor wherein the series inductor is shared between the first and second rectifiers.

Abstract: A power electronic converter for use in high voltage direct current power transmission and reactive power compensation which includes at least one converter limb including first and second DC terminals for connection in use to a DC network. The or each converter limb includes at least one first converter block and at least one second converter block connected between the first and second DC terminals. The or each first converter block includes a plurality of line-commutated thyristors and at least one first AC terminal for connection in use to an AC network. The or each second converter block includes at least one auxiliary converter including a plurality of self-commutated switching elements. The self-commutated switching elements are controllable in use to inject a voltage to modify a DC voltage presented to the DC side of the converter limb and/or modify an AC voltage and an AC current on the AC side of the power electronic converter.

Abstract: A method and an apparatus for controlling a grid-connected converter which includes a boost converter, a buck converter, and a current source inverter having an output CL filter. An input of the buck converter input is connected to an output of the boost converter, and an input of the current source inverter is connected to an output of the buck converter. The method includes controlling a boost converter input voltage, controlling a boost converter output voltage through control of a buck converter output voltage, and controlling the current source inverter to produce an AC current from the buck converter output voltage. The apparatus implements the method.

Abstract: Apparatus and methods in accordance with this invention provide a multi-cell power supply for receiving power from a source and delivering power at an output terminal to a load. The multi-cell power supply includes a first power cell coupled to the source, and a first current sensor circuit. The first power cell provides a first output current, and includes a first output terminal coupled to a reference node of the multi-cell power supply, and a second output terminal coupled to the output terminal. The first current sensor circuit includes a first current sensor and a power supply. The first current sensor is coupled to the first output terminal of the first power cell, and measures the first output current. The power supply is coupled to either the reference node or a floating ground node of the first power cell, and provides power to the first current sensor.

Abstract: A series-connected multi-level power conversion device according to an aspect of embodiments includes a multi-winding transformer and a power conversion unit. The multi-winding transformer has a relationship that n secondary windings respectively connected to n single-phase power converters in the same output phase have a voltage phase difference of 60/n degrees and a relationship that the m secondary windings respectively connected to the m single-phase power converters corresponding to the m output phases have a voltage phase difference of 60/m degrees.

Abstract: Converter control system coupled between a wind turbine generator and the electric power distribution grid, comprising at least two converter modules connected in parallel which are enabled/disabled by out-of-phase pulse-width modulation (PWM) patterns. The control device guarantees dynamic switching of the converter modules irrespective of the enabling or disabling of at least one converter module, constantly delivering electric power to the distribution grid.

Abstract: A technology is disclosed for controlling switching of power converters included in a power converting system. Phase angles are allocated to a plurality of sub-units corresponding to the power converters, and the respective sub-units create local switching carriers based on the allocated phase angles. The sub-units compare a reference AC voltage with the local switching carriers, and switch the power converters according to the result of the comparison.

Abstract: A direct current to direct current (DCDC) voltage converter is described comprising a controller and at least one converter circuit. The converter circuit comprises at least first and second inductors, each having an input and an output; a first input switch connected to the input of the first inductor; a second input switch connected to the input of the second inductor; and an output switch connected to the outputs of the inductors for selectively combining the outputs to form a parallel combination of the inductors or a series combination of the inductors. The controller generates signals for selectively connecting the first and second input switches and the output circuit between a pair of power supply input terminals and a pair of power supply output terminals. In response to appropriate signals from the controller, the converter circuit can be operated as a buck converter or a boost converter.

Abstract: A power supply device that is able to switch between rectifier circuits in accordance with the voltage of a multi-phase AC power supply, and able to accommodate different power supply voltages. The power supply device has rectifier circuits that include a first circuit that rectifies a line voltage of the AC power supply, converting it into a direct current voltage of a first predetermined value, when the voltage of the AC power supply is a predetermined value or less, and a second circuit that rectifies a phase voltage of the AC power supply, converting it into a direct current voltage of a second predetermined value, when the voltage of the alternating current power supply exceeds the predetermined value. The first and second circuits operate in such a way that the AC input current is of the same phase as the voltage of the AC power supply.

Abstract: A power conditioner that suppresses distortion in a waveform of a sinusoidal generated voltage includes a first and second group including two switches each connected in inverse parallel and in series. The power conditioner alternately turns on and off both switches in the first group at a prescribed chopping frequency and alternately turns on and off both switches in the second group at a PWM frequency higher than the chopping frequency. If control is performed with a dead-time provided in the on/off timing for both switches in each group, the power conditioner adjusts and controls the on/off duty for the second group switches to correspond to the effective on drive in one switch by each diode during the dead-time for each switch in the first group.

Abstract: With a power conversion device, it is possible to lengthen the lifespan of a mechanical switch by preventing an absorption by the mechanical switch of induction energy accumulated in a reactor when there is a problem. When a mechanical switch is turned off when there is a problem, an absorption by the mechanical switch of induction energy accumulated in a reactor is prevented by the energy accumulated in the reactor being released to a capacitor via a diode, thus enabling a lengthening of the lifespan of the mechanical switch.

Abstract: A power supply apparatus determines that an input AC voltage has reached a voltage at which a power supply control IC can start operating, based on the voltage at an auxiliary winding of a transformer included in a first converter. Note that since the first converter operates so as to maintain a constant voltage at the auxiliary winding, whether the input AC voltage has fallen to an operation lower limit voltage or lower cannot be detected by only monitoring the voltage at the auxiliary winding. The power supply apparatus monitors a second voltage that is proportional to the input AC voltage is generated from the voltage being applied to the primary side of a second converter. Accordingly, the power supply control IC starts and stops operating in accordance with the input AC voltage.

Abstract: An uninterruptible power supply includes plural power units, plural output capacitor units, a capacitor energy bleeder circuit, plural output units, a detecting unit and a controlling unit. The capacitor energy bleeder circuit is electrically connected to the plural output capacitor units. The plural output units are connected with each other in parallel to issue the output voltage to the power output side and avoid returning electrical energy from the power output side back to the capacitor energy bleeder circuit. The detecting unit is used for detecting operating statuses of the plural power units. The controlling unit is used for controlling operations of the plural power units and the capacitor energy bleeder circuit. In response to a to-be-interrupted status of a specified power unit, the controlling unit controls the capacitor energy bleeder circuit to discharge electrical energy of the output capacitor unit corresponding to the specified power unit.

Abstract: A power supply that provides a supply voltage to an integrated circuit (IC) includes high and low power regulators and a power management circuit. The high power regulator regulates the supply voltage at a first voltage level and the low power regulator is set to an inactive mode when the IC is in a RUN mode. When the IC transitions from the RUN mode to a STOP mode, the high power regulator stops regulating and the supply voltage is maintained at a second voltage level, while the lower power regulator is set to an active mode for regulating the supply voltage at a third voltage level. A fallback signal is generated when the supply voltage drops below a first threshold value after which the low power regulator is set in the inactive mode and the high power regulator is configured to regulate the supply voltage at a fourth voltage level.

Abstract: An energy conversion system and method perform active control of leakage current in multi-level grounded inverters. First and second subsystems each include positive and negative DC source terminals, at least first and second capacitors coupled between the positive and negative terminals to define a common bulk node for the respective subsystem, a DC/DC converter for regulating voltages across the capacitors, and an inverter. The inverters are coupled in parallel to an AC load. First and second grounding branches are homogenously coupled to terminals in the first and second subsystems, respectively, and to the same ground terminal. Control circuitry detects a leakage current value through the ground terminal, generates leakage current control signals for the respective DC/DC converters based at least in part on the detected leakage current value and a reference current value, and communicates the control signals to the DC/DC converters.

Abstract: Multi-level power converters are disclosed. In one embodiment, a multi-level power converter includes an input for receiving an input voltage and a converter output for providing a variable output voltage. The multi-level power converter includes a plurality of switching circuits. Each switching circuit is connected to the input in parallel with each other switching circuit. Each switching circuit includes an output. Each switching circuit is selectively operable to couple its output to the input voltage or a reference voltage. The multi-level power converter includes a parallel multi-winding autotransformer (PMA). The PMA includes a plurality of windings and a magnetic core having a plurality of magnetically connected columns. Each winding is positioned around a different one of the columns and has a beginning and an end. The output of each switching circuit is coupled to the beginning of a different winding. The end of each winding is connected to the converter output in parallel with each other winding.

Abstract: A voltage converting device includes first to third voltage converters, each including a capacitor, a pair of charge switches for charging the capacitor, a pair of first output switches for outputting a first output voltage through the capacitor, and a pair of second output switches for outputting a second output voltage through the capacitor. Via timing control of the switches, outputs of the first and second output voltages are substantially continuous and are prevented from floating.

Abstract: A power converter includes a booster circuit, an inverter circuit, a hysteresis control circuit, and a proportional-integral control circuit. The booster circuit boosts DC power of a DC power source. The inverter circuit converts the DC power outputted from the booster circuit into AC power and outputs the AC power to a system. The hysteresis control circuit controls the inverter circuit by hysteresis control so that the AC power can be outputted to the system when an AC voltage of the system is less than a DC voltage of the power source. The proportional-integral control circuit controls the booster circuit by proportional-integral control so that the AC power can be outputted to the system when the AC voltage of the system is larger than the DC voltage of the power source.

Abstract: Disclosed here is a grid-interactive photovoltaic generation system having power quality improvement and power saving functions. The grid-interactive photovoltaic generation system includes a solar cell array, a first inverter, and a second inverter. The solar cell array receives solar light and generates predetermined power. The first inverter converts the power, generated by the solar cell array, into power required by a grid line. The second inverter is connected to the first inverter, and steps down power, which will be supplied to a load, to an appropriate voltage.

Abstract: Apparatus and methods in accordance with this invention provide a multi-cell power supply for receiving power from a source and delivering power at an output terminal to a load. The multi-cell power supply includes a first power cell coupled to the source, and a first current sensor circuit. The first power cell provides a first output current, and includes a first output terminal coupled to a reference node of the multi-cell power supply, and a second output terminal coupled to the output terminal. The first current sensor circuit includes a first current sensor and a power supply. The first current sensor is coupled to the first output terminal of the first power cell, and measures the first output current. The power supply is coupled to either the reference node or a floating ground node of the first power cell, and provides power to the first current sensor.

Abstract: In the field of voltage source converters which provide high voltage direct current (HVDC) power transmission and reactive power compensation there is a need for an improved power electronic module which exhibits high efficiency, provides a safe failure mode, and is tolerant of faults. A power electronic module (30; 70), for use in a chain-link converter of a voltage source converter providing high voltage direct current power transmission and reactive power compensation, comprises a first set (32) of series-connected switching elements connected in parallel with an energy storage device (34). The first set (32) of series-connected switching elements includes a first latching switching element (38) and a first non-latching switching element (40).

Abstract: A power electronic converter for use in high voltage direct current power transmission and reactive power compensation comprises three converter limbs, each converter limb including first and second DC terminals for connection in use to a DC network and an AC terminal for connection in use to a respective phase of a three-phase AC network, each converter limb defining first and second limb portions being connected in series between the respective AC terminal and a respective one of the first and second DC terminals, each limb portion including at least one switching element being controllable in use to facilitate power conversion between the AC and DC networks, the power electronic converter further including a plurality of auxiliary units, each auxiliary unit being operably associated with the respective phase of the AC network, each auxiliary unit including at least one module including a voltage source, the limb portions being controllable in use to define at least one three-phase static synchronous compen

Abstract: A power supplying device having programmable current-balancing control includes at least two power modules in parallel. Each power module includes a power convertor, a current sensing component, a tuning circuit, a current-balancing control circuit and an output voltage controller. The power convertor provides power to a load via an output end. The current sensing component senses output current of the power convertor to generate a current sensing signal. The tuning circuit generates a tuning signal according to a control signaling from a communicating port. The current-balancing control circuit receives the current sensing signal and the tuning signal. The current-balancing control circuit generates a current-balancing signal according to the current sensing signal. The current-balancing control circuit generates a voltage control signal according to the tuning signal.

Abstract: A control method of a converter system includes: sampling a current of each three-phase winding to obtain a real-time current of each converter; obtaining a mean current by averaging the real-time current of each secondary converter and the real-time current of the primary converter, and transferring the mean current to each secondary converter; obtaining the differential-mode current corresponding to each secondary converter according to the mean current and the real-time current of each secondary converter; performing a circulation current control on the mean current and the differential-mode current of each secondary converter based on a d-q coordinate system to generate a mean-current conditioning signal and a differential-mode current conditioning signal, thereby controlling each secondary converter; and obtaining a sum of the differential-mode current conditioning signal of the secondary converters and negating the sum to obtain a differential-mode current conditioning signal of the primary converter, t

Abstract: A resonant power converter draws current from a source that provides a supply current. Multiple quasi-resonant converters are interleaved and each quasi-resonant converter receives the supply current and forms a phase-shifted current according to drive signals supplied by a controller. Each phase-shifted current includes a dead-time delay and is phase-shifted relative to the other phase-shifted currents. The dead-time delay is determined as a time value within a calculated dead-time delay range having a dead-time delay minimum and a dead-time delay maximum. The outputs of each quasi-resonant converter are added together thereby reducing the AC components of current. Two, three, or four quasi-resonant power converters can be interleaved, each forming phase-shifted currents that are phase-shifted relative to the other phase-shifted currents.

Abstract: The configurations of a parallel-connected resonant converter circuit and a controlling method thereof are provided in the present invention. The proposed circuit includes a plurality of resonant converters, each of which has two input terminals and two output terminals, wherein all the two input terminals of the plurality of resonant converters are electrically series-connected, and all the two output terminals of the plurality of resonant converters are electrically parallel-connected.

Abstract: An alternating current power supply device comprises a DC power supply for generating direct current power, a plurality of, e.g., three first DC/AC inverter to third DC/AC inverter which are arranged in parallel and electrically connected to the DC power supply, for converting the direct current power generated by the DC power supply into alternating current power and supplying the alternating current power to a load, and a control unit for controlling the driving of the first DC/AC inverter to the third DC/AC inverter. The capacitance A of the first DC/AC inverter is set to W/6, the capacitance A of the second DC/AC inverter is set to W/3, and the capacitance A of the third DC/AC inverter is set to W/2.

Abstract: An adaptive controller for a static compensator (STATCOM) to enhance voltage stability comprises an outer voltage regulator loop and an inner current regulator loop. Each of the outer loop and the inner loop comprises a proportional integral controller. The outer loop adjusts proportional and integral control gains of voltage regulator. The inner loop adjusts proportional arid integral parts of current regulator gains. The automatic adjustment of these regulator gains is adaptively determined such that the voltage at the controlled bus follows a desired voltage, reference curve over time returning to a desired steady-state condition under various disturbances such as changes in load and/or transmission network. Thus, the adaptive controller can achieve a plug-and-play feature for a STATCOM without human intervention.

Abstract: A voltage source converter for a HVDC power transmission system is disclosed. According to one aspect, the voltage source converter includes at least one phase element having series connected diodes configured to interconnect, in use, a DC network and an AC network. The voltage source converter further includes at least one auxiliary converter configured to act as a waveform synthesizer to modify the DC voltage presented to the DC side of one or more phase elements.

Abstract: The disclosure provides a power factor correcting (PFC) circuit, a power supply and a method of manufacturing a power converter. In one embodiment, the PFC circuit has a positive input terminal, an output terminal and a ground terminal and includes: (1) a power factor inductor coupled in series between the positive input terminal and the output terminal, (2) a main switch configured to periodically connect the power factor inductor to the ground terminal and (3) a clamping capacitor coupled to the power factor inductor and configured to provide zero turn-off loss for the main switch.

Abstract: Methods and systems for dropping and/or adding phases in multiphase regulators according to various aspects of the present invention may operate in conjunction with multiple output circuits configured to deliver power to a load and a controller. The controller may be connected to each of the output circuits, such as to drive the output circuits. The controller may be adapted to selectively disable and/or enable phases. For example, the controller may disable one output circuit without disabling another output circuit. In addition, the controller may smoothly reduce the power delivered to the load by the output circuit prior to disabling it, for example to control output glitches.

Abstract: A method and apparatus are provided for operating a converter circuit, which includes n input phase connections and p output phase connections, where n?2 and p?2, and (n·p) two-pole switching cells for switching at least one positive and negative voltages between the poles. Power semiconductor switches of the switching cells are driven a drive signal. To reduce undesired circulating currents and adjust the mean voltage deviation of capacitive energy storage of all the switching cells to zero, an inductance is connected into each series connection, with a switching cell together with an inductance in each case forming a phase module. For each phase module, the drive signal is formed from a reference signal based on the voltage across the phase module and from a voltage signal across the inductance. The voltage signal is formed from an intermediate setpoint value of the current through the phase module.

Abstract: A resistance compression network to shape an input impedance at a port for transferring energy to multiple loads at a first frequency includes first and second transmission line segments having outputs for coupling to first and second loads and having different electrical lengths at a first frequency and a compression port coupled to inputs of both the first and the second transmission line segments. Over a set of operating conditions of interest, an equivalent resistance looking into the compression port at the frequency varies over a first resistance range as equivalent resistances of the first and second loads vary over a second resistance range and a range ratio associated with the first resistance range is less than a range ratio associated with the second resistance range and the range ratio of a subject range is a ratio of a largest resistance value in the subject range to a smallest resistance value in the subject range.

Abstract: The present invention relates to a switch control device, a multi-channel converter including the same, and a switch control method thereof. A multi-channel converter includes at least two converters, and each converter includes at least one power switch. The multi-channel converter supplies the sum of the output power of at least two converters to the load. The switch control device generates at least two gate signals switching operation of each of at least one power switch of at least two converters. The switch control device modulates a switching frequency of at least one power switch according to the load, determines the number of phases of the multi-channel converter according to the load, and generates a gate signal for the phase difference corresponding to the number of the determined phases between at least two gate signals to be generated.

Abstract: The present invention relates to an electrical converter for power supply, which is constructed from individual modules. Each of the identical modules includes a module capacitor and can be switched by switching elements such that the module capacitors of the modules may be connected in series or in parallel, or a current flow takes place through the modules without charging or discharging the module capacitor. In this manner, the voltage can be connected across the terminals of the converter by a corresponding control of the switching elements in stages with low loss levels. According to the invention, the voltages of these capacitors are adjusted with respect to each other by load balancing prior to parallel connection of the capacitor modules so that the corresponding losses are minimized.

Abstract: A method of balancing reactive power at a power delivery system is disclosed. The method may include operating a power delivery system that may have a plurality of power cells that are electrically connected to a first transformer comprising one or more primary windings and a plurality of secondary windings such that each cell is electrically connected to one of the secondary windings and a plurality of the secondary windings are phase-shifted with respect to the primary windings. The method may further include controlling the reactive current flow at each power cell by calculating, at a first controller, a reactive current flow adjustment for at least one power cell so that reactive current flow is balanced among each of the plurality of power cells. Each cell may include a plurality of switching devices.

Abstract: An electronic driver circuit for LEDs and LASERs is provided for use in time-of-flight applications featuring a high efficiency of energy-conversion and a high precision of distance-measurements based on a dual conversion circuit. A voltage to voltage DC-DC conversion is hereby merged with a DC-voltage to pulsed-current booster, this booster operating at a time-of-flight modulation frequency. At the start of a new measurement cycle, the PWM signal for driving the DC-DC conversion is updated in response to currents observed during previous illumination periods.

Abstract: A voltage-regulating circuit according to the present invention includes a power conversion circuit, an input voltage detecting circuit and a feedback circuit. The power conversion circuit includes at least one switch element, wherein during operation of the at least one switch element, an input voltage is converted into a transition voltage. The input voltage detecting circuit is connected to the power conversion circuit for outputting a detected voltage signal corresponding to the input voltage. The feedback circuit is connected to the power conversion circuit and the input voltage detecting circuit for generating a feedback control signal. In such way, as the input voltage is changed, the feedback circuit will adjust to make the transition voltage changed as with the change of the detected voltage signal corresponding to the input voltage.

Abstract: An example power supply includes a first power converter, a second power converter, and a shared clamp reset circuit. The first power converter is adapted to convert an input to a first voltage output and includes a first diode and a first transformer having a first primary winding. The second power converter is adapted to convert the input to a second voltage output and includes a second diode and a second transformer having a second primary winding. The shared clamp reset circuit is included in the first power converter and is coupled to the cathode of the first diode. The shared clamp reset circuit also includes a clamp connection that is coupled to the cathode of the second diode. The shared clamp reset circuit is adapted to manage leakage inductance energy within the first transformer and within the second transformer.

Abstract: Between a direct-current power source and a connection point where a resonance current flowing in an opposite direction from a main current joins the main current from the direct-current power source in a resonant converter, there is provided a current blocking circuit which blocks the resonance current toward the direct-current power source. In consequence, it is possible to prevent the reverse charging of the direct-current power source with the resonance current which realizes soft switching in the resonant converter.

Abstract: A power system and a control method thereof are disclosed. The power system comprises: providing a plurality of power sources; electrically connecting a plurality of converters between the power sources and at least one load, wherein the converters are electrically connected to the power sources respectively in a one-to-one manner; and positive feed-forward controlling each of the converters by using a positive feed-forward control circuit electrically connected to one of the power sources in a one-to-one manner, for the use to protect the input voltage source from over-current drawing by reducing the input current of the converter when the source voltage drops, regardless constant output-voltage.

Abstract: In a control apparatus for an inverter generator having a first, second and third windings wound around an alternator driven by an engine, and first, second and third inverters adapted to convert alternating current outputted from the first, second and third windings into direct current and invert the converted direct current into single-phase alternating current in a desired frequency so as to supply to the electric load, there is provided with an actuator (stepper motor) to open and close a throttle valve of the engine, and it is configured to detect output powers (effective powers) of the first, second and third inverters, to determine a target engine speed based on the detected output powers, and to control an operation of the actuator so that the engine speed converges at the determined target engine speed.

Abstract: An inverter and a grid-connected power generation system are provided to efficiently reduce the electric energy loss due to a DC boosted circuit, improve the efficiency of a PV system, and increase lifetime of the inverter. The inverter comprises: a DC boosted circuit; an inversion circuit connected to a output end of the DC boosted circuit; and a bypass circuit, of which an input end is connected to a positive electrode input end of the DC boosted circuit, and an output end is connected to a positive electrode output end of the DC boosted circuit.

Abstract: A method is provided for operation of a converter circuit. The converter circuit has at least two phase modules, where each phase module has a first and a second sub-converter system, and the sub-converter systems for each phase module are connected in series with one another. Each sub-converter system includes a plurality of series-connected two-pole switching cells. In the method, the control signals for the switching cells are additionally formed from a damping signal. The damping signal is formed from a measured current through the respective sub-converter system and from a predeterminable resistance value, in order to attenuate undesirable currents in the sub-converter systems.

Abstract: A full bridge switching circuit includes a converter circuit including first and second converters. The first converter includes a first transformer and a first switching element part to control the first transformer in response to a first switching signal. The second converter includes a second transformer and a second switching element part to control the second transformer in response to a second switching signal. The first and second transformers are controlled by the first and second switching element parts to output first and second feedback signals, respectively. The full bridge switching circuit further includes a third switching element part having a third switching input connected to the first and second transformers, and an IC circuit to generate an OR signal by an OR operation of a first control signal generated from the first feedback signal and a second control signal generated from the second feedback signal.

Abstract: A control and driving device of a high voltage power supply (HVPS) of an electronic apparatus, such as an image forming apparatus, including an input to receive a signal supplied to the HVPS, a control and driving circuit to control and drive the signal received at the input, and an output to output the controlled and driven signal to a transformer of the HVPS, wherein the input, control and driving circuit, and output are integrated into one physical module.

Abstract: Each of master and slave switching power supply apparatuses (2m, 2s) has an IGBT (10m or 10s) switching-controlled by a PWN pulse signal produced, based on a clock signal, by a switching device driving PWM pulse output section (28m or 28s), to thereby provide DC power in parallel to a load (5). The clock signal produced in the master switching power supply apparatus (2m) is coupled to the slave switching power supply apparatus (2s) through a photocoupler (36m) in the master switching power supply apparatus (2m) and a photocoupler (38s) of the slave switching power supply apparatus (2s). Also, the clock signal developed at the output of the photocoupler (36m) is coupled through a photocoupler (38m) to the master switching power supply apparatus (2m). The photocouplers (36m, 38m, 38s) have the same delay characteristic.