Abstract: A power supply circuit, a compensation circuit and a harmonic distortion compensation method thereof are disclosed. The power supply circuit includes a rectifier and filter module, a main power stage module, a voltage waveform detection module and a compensation module. The rectifier and filter module converts an AC voltage into a DC voltage. The main power stage module receives the DC voltage and provides power to a load. The voltage waveform detection module is configured to detect a waveform of the DC voltage and derive, from the waveform, information about each cycle of the DC voltage. The compensation module is configured to generate a compensation signal based on the information about each cycle of the DC voltage and trigger the main power stage module to perform compensation operation based on the compensation signal. The compensation operation is performed to accomplish total harmonic distortion compensation of the power supply circuit.

Abstract: Aspects of direct current (DC)-DC converters with an integrated matrix transformer and multiphase current doubler rectifiers are described. In some examples, a DC-DC converter can include a matrix transformer that has multiple magnetically integrated transformer components that are magnetically integrated using transformer components that share a top plate and a bottom plate. A multiphase current doubler rectifier can include multiple synchronous rectifiers corresponding to the plurality of transformer components of the matrix transformer.

Abstract: A power supply system includes a first saturable reactor electrically connected to a first AC phase input, to a second AC phase input, and to a third AC phase input. The first saturable reactor is electrically connected to a first DC output. A second saturable reactor is electrically connected in parallel with the first saturable reactor to the first AC phase input, to the second AC phase input, and to the third AC phase input. The second saturable reactor is electrically connected to a second DC output. A reactor controller can be operatively connected to the first saturable reactor and to the second saturable reactor to regulate DC output voltage to the first and second DC outputs.

Abstract: A circuit includes a transistor, with a resonant tank coupled between a DC supply node and a first conduction terminal of the transistor. A gate driver generates a gate drive signal for biasing a control terminal of the transistor to cause it to conduct current through the resonant tank. Control circuitry monitors a voltage across the transistor to determine that the transistor is an overvoltage condition if that voltage exceeds a threshold, and monitors a current through the transistor to determine that the transistor is an overcurrent condition if that current exceeds a threshold. If overvoltage is determined, the control circuitry causes the gate driver to pull up the gate drive signal. If overcurrent is determined, the control circuitry causes the gate driver to pull down the gate drive signal. If either overvoltage or overcurrent is present, a pulse width of the gate drive signal is reduced.

Abstract: A voltage doubling circuit that increases input voltage to higher output voltage connected to a variable frequency drive. The voltage doubling circuit can include a power input that receives the input voltage from a power source and a first capacitor bank and a second capacitor bank connected with the power input. A current-limiting surge suppressor is positioned between the power input and the first capacitor bank and the second capacitor bank. The current-limiting surge suppressor includes a first current-limiting path and a second bypass path. A drain, when operable, dissipates the charge of the first capacitor bank and the second capacitor bank. A variable frequency drive (VFD) is operable in response to the higher voltage output from the first capacitor bank and the second capacitor bank.

Abstract: A current fed high-frequency isolated matrix converter and the corresponding modulation and control schemes are provided. The converter includes a current source full-bridge converter, a high-frequency transformer, a matrix converter, and a three-phase filter. An optimized space vector modulation solution is used for controlling the converter, and by comparing magnitudes of three-phase filter capacitor voltages to determine an action sequence of space vectors, switch tubes are turned on at zero voltage. A current source full-bridge circuit adopts a commutation strategy of a secondary clamping, and by calculating a leakage inductive current commutation time, full-bridge switch tubes are turned off at zero current to achieve safe and reliable commutation, and having advantages of a low system loss, a high efficiency, and a high power density.

Abstract: To provide a voltage converter configured to suppress individual variation in voltage conversion ratio and configured to achieve a high voltage conversion ratio. A voltage converter comprising a reactor, a switching element, a diode, a current sensor, and a controller, wherein the controller detects a current value of the reactor several times in a switching period; wherein the controller calculates an estimated execution ON time length from a transition of a current value of the reactor detected in the switching period; wherein the controller calculates a difference between the estimated execution ON time length and a command ON time length instructed by the controller; and wherein, by using the difference, the controller corrects the command ON time length of the time when performing any of subsequent ON commands in a range not exceeding a predetermined command ON time upper limit value.

Abstract: The invention relates to an elevator comprising at least one elevator car moved by at least one elevator motor, which elevator motor is driven by a frequency converter controlled by a control device of the elevator, the frequency converter comprising a rectifier bridge, an inverter bridge and a DC link connected in-between, the inverter bridge being connected to the elevator motor and the rectifier bridge being connected to AC mains via three phase supply lines comprising an LCL-filter and a mains switch.

Abstract: A converter and a power supply system are disclosed, and relate to the power electronics field, to resolve a problem that a sampling circuit in an OBC circuit is relatively complex. The converter includes an alternating current unit, a switching unit, a conversion unit, a direct current unit, and a controller. The alternating current unit includes a U line, a V line, a W line, and an N line. The N line is connected to a ground of the controller, so that the controller can be directly connected to the U line, the V line, and the W line, to collect a voltage of the U line, a voltage of the V line, and a voltage of the W line. This simplifies the sampling circuit.

Abstract: In an example, a system comprises a boost power factor correction (PFC) converter that includes a thermistor, an inductor, and a transistor and a PFC controller coupled to a common node. The PFC controller includes a comparator coupled to a threshold voltage source and to a terminal of the transistor. A first flip-flop is coupled to the comparator and to a control terminal of the transistor. A zero current detector is coupled to the inductor. A timer is coupled to the comparator and to the zero current detector. A second flip-flop is coupled to the timer and to the control terminal of the transistor. An AND gate is coupled to the first and second flip-flops. The circuit includes third and fourth flip flops.

Abstract: A control method of a switching circuit, a control circuit of the switching circuit, and the switching circuit are provided. The switching circuit includes an inductor or a transformer. An operational amplification is performed on an output feedback voltage and a first reference voltage of the switching circuit to obtain a compensation voltage. The compensation voltage controls an on-time of a main switch of the switching circuit. When the current of the inductor or the transformer drops to a threshold, after a time, the main switch is switched from off to on, and the output feedback voltage controls the time. When the output feedback voltage is higher than a first threshold voltage, the compensation voltage is pulled down. When the output feedback voltage is lower than a second threshold voltage, the compensation voltage is pulled up.

Abstract: A method and an apparatus are presented which enable the identification of a capacitor fault in a given string of a capacitor bank, based on the computation of the string impedance by measuring the string AC current and voltages, where each string includes a plurality of capacitor elements connected in series. The method consists of measuring the string capacitive impedance and comparing this value with a previously measured capacitive impedance of the same string. If a difference between these two values is obtained, which exceeds a given threshold for a certain duration, a fault is recorded.

Abstract: An output filter for a power conversion system having a plurality of power converters connected in parallel, the output filter including a magnetic core and a plurality of filtering windings each wound around a corresponding one of a plurality of segments of the magnetic core and corresponding to one of the plurality of power converters, each of the plurality of filtering windings including a free-end configured for connection to an output of a corresponding one of the plurality of power converters and a second end, the second ends of all of the filtering windings being electrically connected to each other in a common connection; at least one additional winding wound around the additional segment of the magnetic core, the additional winding having a free-end for being connected to an electrical grid and a second end connected to the common connection.

Abstract: A power conversion apparatus includes: a converter including switching elements and configured to convert an AC voltage supplied from an AC power supply through a switch unit into a DC voltage; a filter provided between the switch unit and the converter and including reactors and capacitors, the filter being configured to remove noise; and a control unit configured to discharge electric charge stored in the capacitors by setting the switching elements into an ON state after opening the switch unit.

Abstract: A power conversion apparatus includes: a converter converting AC voltage supplied from an AC power supply via a switch unit, into DC voltage; a smoothing capacitor smoothing the DC voltage output from the converter; a resistor suppressing electric current flowing into the smoothing capacitor; a switch short-circuiting the both ends of the resistor; a filter including reactors and capacitors and that removes noise; and a control unit controlling opening and closing of the switch unit and the switch. The control unit changes the switch unit from the open state to the closed state with the switch in an open state if the voltage across the smoothing capacitor is lower than a voltage threshold, and changes the switch unit from the open state to the closed state with the switch in an closed state if the voltage across the smoothing capacitor is equal to or greater than the voltage threshold.

Abstract: A power converter includes a full-bridge conversion circuit. The full-bridge conversion circuit includes a first leg and a second leg. The first leg includes at least two switches coupled to each other at a first node, and the second leg includes at least two switches coupled to each other at a second node. The power converter further includes an AC filter. The AC filter includes a first inductor, a second inductor and a capacitor. The first inductor includes a first end coupled to the first node and a second end could be couple to a grid. The second inductor includes a first end coupled to the second node and a second end could be couple to the grid. The capacitor includes a first end coupled to the second end of the first inductor and a second end coupled to the second leg. The first end of the capacitor is electrically coupled to the second end of the first inductor during a cycle of an AC voltage of the grid.

Abstract: An energization evaluation test equipment for an input filter of a large capacity PWM converter by reducing the power supply capacity to the equipment under test is provided. The energization evaluation test is equivalent to an actual load test. An equipment under test has an input filter connected to an output terminal of an AC power source and a PWM converter connected to an output terminal of the input filter to convert an AC power source to a DC power source.

Abstract: A device for harvesting electrical energy includes a rectifier and a control device. The rectifier includes a first charging circuit for harvesting energy from a positive voltage of an energy harvester, and a second charging circuit for harvesting energy from a negative voltage of the energy harvester. The charging circuits include a common coil and a common electronic switch. Furthermore, each of the charging circuits includes a capacitor and a blocking element. Because the charging circuits use the coil jointly, the device is designed in a simple and compact manner. In addition, the energy harvesting is efficient, due to the one-stage AC-DC conversion and due to a maximum power point tracking function of the control device.

Abstract: A light emission control device controls a first switching element of a light source circuit including a first resistor, a light emitting element, and the first switching element coupled in series between a first power supply node and a second power supply node set to a lower potential than the first power supply node. The light emission control device includes a second detection circuit that compares a first potential difference between both ends of the first resistor with a determination value, a light emission control circuit that outputs a first control signal that controls on/off of the first switching element, and a logic determination circuit that determines whether or not the first switching element is short-circuited.

Abstract: A controlling device (100) for executing either one of a current vector control and a voltage phase control such that supply power to an electric machine (9) is controlled in accordance with an operating state of the electric machine (9) calculates a voltage command value for the voltage phase control based on a voltage norm command value indicative of a magnitude of a supply voltage to the electric machine (9) and a voltage phase command value indicative of a phase of the supply voltage. The controlling device (100) calculates a state amount of either one of magnetic flux generated in the electric machine (9) and a parameter correlated to the magnetic flux, based on a current supplied to the electric machine (9) and changes the voltage norm command value in accordance with the state amount.

Abstract: A method for controlling a three-phase Vienna rectifier, including a plurality of controlled power switches, each associated with an electrical phase; the method including: transforming three provided reference line voltages into three phase voltages; calculating a homopolar component to be injected according to the sign of the phase voltage values and to the average value of the phase currents of the three-phase Vienna rectifier; calculating “modulating” values for each phase of the three-phase Vienna rectifier according to the calculated homopolar component to be injected and the three phase voltages; and generating six signals for switching the controlled power switches, according to the sign of the phase currents of the three-phase Vienna rectifier and the “modulating” values that were calculated.

Abstract: A switched capacitor array having a plurality of capacitors arranged in a plurality of branches having different numbers of capacitors, and a plurality of switches connected to selectively couple the capacitors across the input or the output may be used for powering a variety of loads. A switched LED array may be dynamically configured based on a voltage supplied thereto, which may be supplied by a switched capacitor array. A lighting apparatus may be provided with first and second blocks, each block comprising a switched capacitor array, a switched LED array, and a control system.

Abstract: A power converter is electrically connected with an AC power supply via a switch, and is configured with a plurality of unit converters (5) connected in series. A drive circuit (40, 42) drives a plurality of switching elements (11 to 14) of a main circuit (30). An interface circuit (48) outputs a detection value of a voltage sensor (46) to a control device (4). If a bypass switch (7) is turned off when the power converter is activated, each of the plurality of unit converters (5) charges a capacitor (15) using power supplied from the AC power supply. When the power converter is activated, a power supply (50) supplies a power supply voltage to the voltage sensor (46) and the interface circuit (48), prior to the drive circuit (40, 42). The control device (4) turns off the switch when the detection value of the voltage sensor (46) of at least one of the plurality of unit converters (5) is more than or equal to a predetermined value.

Abstract: A linear motor comprises a stator, the stator comprising multiple drive coils and an intermediate circuit electrically conductively connected to each drive coil, the intermediate circuit being configured to exchange energy with each drive coil. The drive coils are arranged along the running rail, where at least one slide comprising a magnet acting as a rotor of the linear motor is movably arranged on the running rail. A controller is configured to independently control each drive coil, so that electrical energy is fed from the intermediate circuit into the drive coils, if a measured intermediate circuit voltage is greater or equal to a predetermined intermediate circuit voltage threshold value, where those drive coils are excluded from the feed-in of the electrical energy which are instantaneously being used for driving or braking the at least one slide and/or have a thermal load which exceeds a predetermined thermal load threshold value.

Abstract: Provided is a method for suppressing common-mode current of neutral line in T-type three-level three-phase inverter, the method of the present disclosure can effectively suppress LC filter resonance contained in the currents of a circulation neutral line and inversion side of a inverter, reduce the common-mode leakage current of the inverter, and improve the performance of the inverter.

Abstract: A filtering arrangement for a system including a power electronics device and an external power storage/discharge element, which power electronics device includes a power module and a three-phase filter between the AC power terminals of the power module and the supplying AC power grid, and which power module includes a DC intermediate power bus, and which three-phase filter between the AC power terminals and the supplying AC power grid includes two three-phase inductors, and which external power storage/discharge element has two DC power terminals which are connected to the DC intermediate power bus of the power electronics device. The filtering arrangement includes a common mode inductor which is connected between the DC power terminals of the external power storage/discharge element and the terminals of the DC intermediate power bus of the power module.

Abstract: A hybrid Cascaded H-Bridge (CHB) converter includes a selective harmonic current mitigation pulse width modulation (SHCM-PWM) unit coupled to an input current and providing an output signal SWSHCM, a phase shift pulse width modulation (PSPWM) unit coupled to the input current and providing an output signal SWPS, a modulation selector coupled to the output signal SWSHCM of the SHCM-PWM unit and the output signal SWPS of the PSPWM unit and providing an output signal SW, and a CHB converter coupled to the output signal SW of the modulation selector. The modulation selector can select one of the output signals (SWSHCM and SWPS) as the output signal SW based on the input current. The hybrid technique is for cascaded multilevel converters which utilizes asymmetric SHCM to mitigate the harmonics generated from PS-PWM to meet harmonic limits with a smaller number of switching transitions and smaller inductance than the conventional PS-PWM technique.

Abstract: A constant on-time isolated converter comprises a transformer with a primary side and a secondary side. The primary side is connected to an electronic switch and secondary-side is connected to a load and a processor. The processor is connected to a driver on primary side through at least one coupling element and to the electronic switch. The processor receives an output voltage or an output current across the load generating a control signal accordingly. The driver receives the control signal through the coupling element and accordingly changes the ON/OFF state of the electronic switch, regulating the output voltage and the output current via the transformer, where the duration of the ON/OFF state of the electronic switch is determined between the moment control signal changes from negative to positive and the moment it changes from positive to negative to achieve a high-speed load transient response.

Abstract: A retrofit Light Emitting Diode, LED, tube to be used in a multi lamp luminaire system is presented, which LED tube comprises a controllable switch circuit arranged to short circuit the LED array of the LED tube such that the LED array does not emit light and such that the current path in the multi lamp luminaire system is not interrupted.

Abstract: In an apparatus for controlling a DC-AC converter including a reactor and a plurality of drive switches and configured to convert DC power supplied via input terminals into AC power and supply the AC power to an AC power source connected to output terminals. In the apparatus, a current corrector is configured to set a current correction value including a harmonic component for a frequency component of a supply voltage of the AC power source that has minima at zero crossings where the supply voltage is zero and superimpose the current correction value on a sinusoidal commanded current generated based on the supply voltage of the AC power source, thereby generating a commanded current after correction. A current controller is configured to operate the drive switches using peak current mode control to control the reactor current to the commanded current after correction.

Abstract: A hybrid Cascaded H-Bridge (CHB) converter can include a selective harmonic current mitigation pulse width modulation (SHCM-PWM) unit coupled to an input current and providing an output signal SWSHCM, a phase shift pulse width modulation (PSPWM) unit coupled to the input current and providing an output signal SWPS, a modulation selector coupled to the output signal SWSHCM of the SHCM-PWM unit and the output signal SWPS of the PSPWM unit and providing an output signal SW, and a CHB converter coupled to the output signal SW of the modulation selector. The modulation selector can select one of the output signals (SWSHCM and SWPS) as the output signal SW based on the input current.

Abstract: The invention relates to a system for generating electric power, comprising: an alternator (1) for coupling with a drive system (7), supplying an AC voltage to an output bus (10); a reversible AC/DC converter (2) in which the AC bus (6) is connected to the output bus (10) of the alternator (1); an electricity-storage element (3) connected to the DC bus (9) of the converter (2); a controller (4) arranged to react to a transient state of load-shedding or charging impact by controlling the converter (2) so as to collect energy on the output bus (10) of the alternator (2) and to store same in the storage element (3) in the case of load-shedding, and to collect energy in the storage element (3) and to inject same into the output bus (10) in the case of charging impact, the converter (2) being controlled so as to inject currents to compensate for harmonic currents into the AC bus (10) of the alternator (1).

Abstract: A method of operating a power supply having a PFC stage and an LLC converter coupled to the PFC stage includes: operating the PFC stage in CCM in a steady-state mode of the power supply using a current mode controller, by implementing a current control loop which has AC input voltage measurements as an input; operating the PFC stage in DCM for at least part of a burst mode of the power supply using a voltage mode controller, by implementing a voltage control loop which does not have AC input voltage measurements as an input; and modifying the voltage control loop if an output of the voltage mode controller in burst mode and which is proportional to power in average current mode control falls outside a predetermined range.

Abstract: The present disclosure relates to a snubber circuit which comprises a static snubber unit, connected in parallel with the switch, for balancing a static voltage sharing across a switch when the switch is in a state of turn-on or turn-off; and a dynamic snubber unit for balance a dynamic voltage sharing across the switch when the switch is in a process of turn-on or turn-off, comprising a dynamic voltage sharing capacitor connected in parallel with the switch and having a relationship between a capacitance and a voltage of the dynamic voltage sharing capacitor; and a controller for controlling the capacitance of the dynamic voltage sharing capacitor to be in a predetermined working area of capacitance rising while the voltage across the switch is increasing. The present disclosure also relates to a power semiconductor device.

Abstract: An MMC includes arms configured with one unit converter or a plurality of cells connected in series. The main circuit of the cell includes a switching element and a DC capacitor. The power supply of the cell lowers voltage of the DC capacitor to generate power supply voltage to be supplied to the control circuit of the cell. The power supply includes a power supply circuit configured to convert input voltage provided between first and second input terminals from the DC capacitor into power supply voltage, a thyristor connected between the first and second input terminals electrically in parallel with the power supply circuit, a current-limiting resistor connected between terminals of the DC capacitor electrically in series with the thyristor, and a control unit configured to fire the thyristor when input voltage applied to the power supply circuit exceeds a threshold voltage.

Abstract: A power converter is provided. The power converter is used to drive a load. The power converter includes an energy storage element for storing a converted power. The power converter provides a determination signal according to a level of an input power, and provides a first notification signal to the load according to the determination signal. The power converter provides a control signal and an enable signal when receiving a second notification signal from the load. The power converter selectively provides the enable signal according to the determination signal, and selectively absorbs a power of the energy storage element according to the enable signal.

Abstract: A control circuit for controlling a Switch-Mode Power Supply (SMPS) includes a current conduction duration determining circuit, an integrator circuit, a feedback circuit, a sawtooth generator circuit, and a gate control circuit. The current conduction duration determining circuit produces a duration signal according to a duration of a current of the SMPS. The integrator circuit produces an integrator output corresponding to an integral over time of a magnitude of the current. The feedback circuit produces a comparison voltage according to an output voltage of the SMPS. The sawtooth generator circuit produces a sawtooth signal using the comparison voltage and duration signal, such as by dividing the comparison voltage by the duration signal. The gate control circuit generates a gate signal for controlling a power switch of the SMPS according to a comparison of the sawtooth signal to the integrator output. The SMPS may be a Power Factor Correction circuit.

Abstract: A power factor correcting device that controls switching of a converter that converts AC voltage inputted via a circuit with a capacitor through which reactive current flows into DC voltage calculates the magnitude of the reactive current based on the magnitude of the AC voltage inputted to the converter and the capacitance of the capacitor and corrects a power factor including the circuit, calculates a target value for a phase delay of the AC current with respect to the AC voltage based on the calculated magnitude and the magnitude of the AC current inputted to the converter or the magnitude of the DC power outputted from the converter, and calculates an operation amount for delaying the phase of the switching based on the calculated target value.

Abstract: A resonator circuit includes: a first inductive element and a second inductive element that is connected to the first inductive element in series; a first capacitive element, connected to a first end of the first inductive element and a first output end of the resonator circuit; and a set of second capacitive elements connected in series, the set of second capacitive elements having one end connected between the first and second inductive elements and having another end connected between the second inductive element and a second output end of the resonator circuit. The intermediate end of the set of second capacitive elements is used as a third output end of the resonator circuit.

Abstract: A PFC circuit according to the invention is connected to a grid, includes an input filter and a rectifier connected to a converter. A control circuit generates the reference current for the current regulator of the converter that controls its input current. Thereby, the reference current is generated by adding an offset current (I0) to a standard reference current and adapting the magnitude of the standard reference current to compensate for a change of the input power resulting from the addition of the offset current (I0). However, due to the addition of the offset current (I0) the magnitudes of some lower harmonic components of the input current of the power supply unit are increased and the magnitudes of some higher harmonic components of the input current are decreased such that the power supply may draw more current from the grid.

Abstract: A reactive power compensator includes a plurality of phase clusters each including a plurality of cells, and a controller configured to control the plurality of phase clusters. When an energy error is generated in each of the plurality of phase clusters, the controller performs control to compensate for the energy error by generating an offset signal having a zero sequence component based on an error energy value of each of the plurality of phase clusters.

Abstract: An augmented power converter may include a motor drive circuit. The motor drive circuit may include a motor drive transformer to convert a two-phase DC voltage to a three-phase output voltage for operating an electrical device. The motor drive circuit may also include a power control component for each phase of the two-phase voltage.

Abstract: The present invention discloses a high power factor phase-cut dimming power supply system, which includes an alternating current power supply, a phase cutting dimmer, a high power factor phase-cut dimming power supply, an LED lamp, or an LED light. The high power factor phase-cut dimming power supply includes an anti-interference circuit that corresponds to and adaptively connect with each other, an active power factor correction circuit, a power conversion circuit, a dimmer current maintaining circuit, a signal conversion circuit, a photoelectric coupler, a PWM signal amplifying circuit and a field effect transistor. The present invention provides a high power factor phase-cut dimming power supply. It has advantages of a high power factor, a load power without any limitation, a high efficiency, an output power as high as several hundred watts. It can be widely used in the field of high power factor phase-cut dimming power supply.

Abstract: A first capacitor is connected between first and second power supply lines. A reactor is connected in series with the first power supply line or the second power supply line. A single-phase AC voltage is applied to a rectifying circuit. The rectifying circuit, which includes the first capacitor and the reactor, outputs a rectified voltage to the first and second power supply lines. A buffer circuit includes a second capacitor provided between the first and second power supply lines. The buffer circuit discharges the second capacitor at a controllable duty ratio. A booster circuit boosts the rectified voltage to charge the second capacitor. A DC current to be input to the booster circuit is reduced more as a voltage across the reactor is higher.

Abstract: A bridgeless PFC boost converter has either a single switching cell or two identical switching cells configured to operate 180 degrees out of phase. A switching cell includes first and second transistor switches coupled to opposing ends of an input AC voltage source, and first and second rectifying diodes, one rectifying diode coupled in series to each of the two transistor switches. A boost inductor is coupled to a junction node between each transistor switch and rectifying diode series. Either a third rectifying diode or a third transistor switch is coupled to a junction node between the input AC voltage source and the first transistor switch. Either a fourth rectifying diode or a fourth transistor switch is coupled to a junction node between the input AC voltage source and the second transistor switch. The rectifying diodes are coupled an output capacitor. Two switching cells can be interleaved.

Abstract: An LED driver of an LED tube includes: an AC-to-DC converting module converting an AC voltage received from a ballast into an intermediate DC voltage that is smaller than or equal to a predetermined threshold voltage, and a DC-to-DC converting module converting the intermediate DC voltage into a DC output voltage for driving LEDs of the LED tube.

Abstract: Circuit and apparatus for improving operating features characteristics of DC power supplies implementing three Phase transformer devices of the type such as 12-step and 24-step transformers. The circuit and apparatus reduces harmonic AC input current while providing almost unity power factor for DC power supply outputs intended for aircraft or marine applications where size and weight are concerns. The circuit includes a passive series connected nonlinear resonant LC circuit connected at each phase of the input to the three phase transformer With the three phase transformer having the added series nonlinear resonant LC circuit, the power supply is enhanced with current limiting for the entire transformer, rectifier and load, due to load shorting, input voltage transients, transformer winding short circuit or rectifier failure. Further, such apparatus provides limiting of power inrush currents during voltage application or turn on, while also providing EMI filtering.

Abstract: A voltage converter system comprises a plurality of voltage conversion circuits, each of the voltage conversion circuits includes a reactor and a switching element, a controller, and a single current sensor connected with the reactors of two voltage conversion circuits and configured to be used in common by the two voltage conversion circuits in order to measure the reactor current. When only one voltage conversion circuit out of the two voltage conversion circuits is driven as an object circuit, the controller repeatedly performs a correction amount learning process. When the measured current value approaches the target value to be within a predetermined range or when the correction amount learning process has been performed a predetermined number of times, the controller changes the object circuit from the one voltage conversion circuit to the other voltage conversion circuit, and repeatedly performs the correction amount learning process.

Abstract: An electronic device includes a controller configured to regulate one or more voltages or currents of a power converter. The controller is configured to receive an input voltage of the power converter, determine whether the power converter is operating in a first mode of operation or a second mode of operation based at least in part on the input voltage, generate a multiplier reference signal for the power converter based on whether the power converter is operating in the first mode of operation or the second mode of operation, and adjust an input current of the power converter based at least in part on the multiplier reference signal. Adjusting the input current includes correcting the input current to be substantially identical in form to the input voltage.

Abstract: A method of controlling a single-phase voltage source AC/DC converting circuit has internal equivalent impedance as seen from an AC terminal, for converting power from a DC voltage source connected to a DC terminal to single-phase AC power or for converting single-phase AC power from a single-phase AC source connected to the AC terminal to DC power in accordance with a pulse width of a gate signal generated based on a PWM command.