Abstract: An efficient and cost effective bidirectional DC/DC converter reduces switch voltage stress via accelerated commutation allowing use of a low-cost passive clamp circuit in boost mode. The converter includes a primary circuit, transformer and secondary circuit. The primary circuit takes the form of a “full bridge converter,” a “push-pull converter,” or an “L-type converter.”. The primary circuit may include a dissipator such as a snubber circuit or small buck converter. A secondary side of the transformer is momentarily shorted by the secondary circuit by, for example, turning on at least two switches in the secondary circuit simultaneously for a minimal calibratable period when a pair of primary circuit controllers turn off to protect the primary circuit switches from voltage spikes during switching conditions.

Abstract: A method and system of controlling half-bridge DC—DC converters to achieve Zero Voltage Switching (ZVS) for at least one of the switches. The soft-switching half-bridge DC—DC converter system includes soft-switching for all switches by adding an additional branch with a switch and a diode across the primary side of an isolation transformer and by applying a Duty-Cycle Shifted PWM Control.

Abstract: A DC to DC switching power converter includes switching elements having capacitive gate control inputs, an energy storage element and driver circuitry. The driver circuitry generates a partial-swing switching signal to at least one of switching elements to achieve efficiency improvement by reducing the energy required to charge and discharge the capacitance of the gate control input. In one embodiment, the switching power converter is fabricated on a semiconductor die to generate an output voltage to one or more functional unit blocks on the die. Several power converters can be combined to form an on-die multiphase power converter.

Abstract: On the basis of: a first calculated value ic which is a product of a calculated value of a time of three-phase output voltages in a state where a positive bus, a negative bus, and a neutral line are connected respectively to three-phase phase output terminals, and a predicted neutral current value in the state; and second and third calculated values icx and icy which are products of a calculated value of a time of the three-phase output voltages that can take state 1 where two of the three-phase phase output terminals are connected to the positive bus or the neutral line, and a remaining one terminal is connected to the neutral line or the negative bus, and state 2 opposite to the state, and predicted neutral current values in states 1 and 2, a time ratio of state 1 and 2 during a PWM period is determined so as to make a current flowing through the neutral line close to zero, or a potential of the neutral line of the three-phase output voltages close to a voltage which is exactly the middle between voltages o

Abstract: A converter circuit with short-circuit current protection having a DC voltage circuit (1) is proposed, which DC voltage circuit (1) is formed by a DC voltage circuit subsystem (2.1), the DC voltage circuit subsystem (2.1) having a first energy store (3) and a second energy store (4), which is connected in series with the first energy store (3), and a fuse (5). Furthermore, the converter circuit has at least one pair of branches (6) provided for each phase (R, S, T) and connected in parallel with the DC voltage circuit (1), each pair of branches (6) having power semiconductor switches. In order to achieve a low-inductance converter circuit, the fuse (5) forms the connection between the first energy store (3) and the second energy store (4).

Abstract: A power supply including an inverter receiving a DC input signal from a DC input source (11). The inverter is comprised of two half bridges (S1A, S2A and S1B, S2B). Each inverter is driven by a signal source (13A, 13B), which outputs an AC signal. The output from each inverter is input to a first stage harmonic filter. The power supply includes an output circuit that includes first and second rectifiers (D1, D2) arranged about a point so that if the inverter attempts to drive the point beyond a predetermined first and second voltage, the respective rectifier conducts in order to return at least one of power and current to the DC input source. The output from the first harmonic filter (L1A, C1; L1B, C1) is output to a second harmonic filter (L2, C2) and is then output from the power supply.

Abstract: A method of controlling an inverter power generation apparatus adapted to stop an operation of an inverter by stopping supplying a drive signal to a switch circuit of the inverter when an overload continuation time exceeds a first setting time in the state where a load current detected by a load current detector is equal to or more than a first overload judgment value and equal to or less than a second overload judgment value, to stop the operation of the inverter when the overload continuation time exceeds a second overload judgment value set in accordance with an output voltage of the inverter in the state where the load current exceeds the second overload judgment value and the output voltage of the inverter is higher than a short circuit judgment value and to stop the operation of the inverter immediately when the load current exceeds the second overload judgment value and the output voltage of the inverter is equal to or less than the short circuit judgment value whereby the inverter can be positively pr

Abstract: For use in a power converter having a power switch and a synchronous rectifier device coupled between input and output thereof, a control circuit, method of disabling a synchronous rectifier device and power converter employing the control circuit and method. In one embodiment, the control circuit includes a synchronous rectifier controller, coupled to the output of the converter and the synchronous rectifier device, that senses time derivative of the output voltage and disables the synchronous rectifier when derivative is negative and greater than a predetermined magnitude.

Abstract: A power supply for performing arc-machining operation includes a primary rectifier connected to the commercial AC power source and an inverter coupled to the rectifier. A switching device is provided between the rectifier and the inverter. By controlling the power supplied from the rectifier to the inverter, the switching device prevents a large switching loss from occurring in the inverter.

Abstract: A switching power supply suitable for driving a load whose load current may fluctuate abruptly comprises a main circuit unit including a switching circuit for converting a DC input voltage to an AC voltage and an output circuit for rectifying the AC voltage to produce a DC output voltage, and a control circuit for controlling the operation of the main circuit unit, the transfer function of the control circuit assuming a first value when the load current supplied by the main circuit unit changes at a rate not exceeding a prescribed rate and assuming a second value exceeding the first value when the load current changes at a rate exceeding the prescribed rate. The switching power supply therefore exhibits markedly improved transient response when the load current changes at a rate exceeding the prescribed rate because the transfer function of the control circuit is increased relative to that under normal condition.

Abstract: An apparatus for protecting an inverter against over current is constructed of a plurality of switching devices connected between the positive and negative terminals of a DC power source. The apparatus has a plurality of detecting devices that convert the currents passing through the plurality of switching devices into voltages and generate detection outputs, a plurality of amplifier circuits, a plurality of comparing devices that supply the detection outputs of the detecting devices to the amplifier circuits and generate an abnormality output if an absolute value of a detection output exceeds a predetermined value, and a protecting device that interrupts the drive of all switching devices if any of the comparing devices issues an abnormality output.

Abstract: A power semiconductor module that automatically sets an optimum dead time without being affected by the switching characteristics or driving mode of individual power semiconductor devices. The power semiconductor module includes a pair of IGBTs disposed in an upper and lower arm, respectively, and driving circuits for driving IGBTs. The power semiconductor module includes current detecting circuits and zero current detecting circuits for detecting that the output current of each of the IGBTs has become nearly zero, an inverting circuit, upper arm driving circuit and lower arm driving circuit for generating actual driving signals for each IGBT, using the output signals of the zero current detecting unit and ON commands for the IGBTs of the other arms.

Abstract: A switching voltage converter in half bridge topology includes a control circuit for achieving a constant locking time for two power switches to switch between a TOP position and BOT position. The TOP switch is realized by one or more parallel-switched n-channel transistors and the BOT switch 3 is realized by one or more parallel-switched p-channel transistors. Both of the power switches are controlled by a gate driver. The reference potential of the gate driver is at the potential of the output signal Uout of the half bridge. The driver is controlled by a switching-signal producing unit at the same reference potential as the driver 1, whereby unit and driver can be directly connected to each other.

Abstract: An H-type motor bridge coil driver circuit is implemented with an electronic switch in each leg segment of an H-shaped circuit, this bridge circuit having its side legs each connected between a power supply and ground, with the inductive load of a motor coil being connectable as the cross leg of the H-shaped circuit. An alternate current path, voltage level stabilizing element may be connected across each leg segment electronic switch. A coil excess energy storage element may be connected to the coil nodes of the circuit, through alternate current path elements and utilized to temporarily store the discharging of the excess coil energy normally available because of the lagging nature of the motor coil current. This temporary storage element then may discharge this energy back to the power supply through a passive circuit element, and reverse polarity protection is included for the power supply.

Abstract: It is an object of the present invention to provide an inverter circuit including a power arm ensuring a high breakdown voltage and having low probability of malfunction. In a power arm element consisting of a switching element and a diode connected in inverse-parallel connection thereto, n free wheeling diodes (n≧2) connected in series are connected in inverse-parallel connection to a switching element (1b). A breakdown voltage between an anode and a cathode of each free wheeling diode is defined to be 1/n of a breakdown voltage of the switching element (1b). That is, the breakdown voltage of each free wheeling diode is reduced to 1/n to reduce a thickness of a n− drift region. A transient voltage characteristic during flow of a free wheeling current can be thereby kept low. The drop in the breakdown voltage is compensated with the n free wheeling diodes connected in series, to thereby ensure breakdown voltage of a degree approximately the same as that of the switching element.

Abstract: A power supply including an inverter receiving a DC input signal from a DC input source (11). The inverter is comprised of two half bridges (S1A, S2A and S1B, S2B). Each inverter is driven by a signal source (13A, 13B), which outputs an AC signal. The output from each inverter is input to a first stage harmonic filter. The power supply includes an output circuit that includes first and second rectifiers (D1, D2) arranged about a point so that if the inverter attempts to drive the point beyond a predetermined first and second voltage, the respective rectifier conducts in order to return at least one of power and current to the DC input source. The output from the first harmonic filter (L1A, C1; L1B, C1) is output to a second harmonic filter (L2, C2) and is then output from the power supply.

Abstract: In a power supply system for converting the output of a DC power supply having an earth capacitance to AC power, an input voltage from an input-voltage detector and an intermediate voltage from an intermediate-voltage detector are input to an input-ripple controller. The latter calculates the difference between ripple voltages of the two voltages. The input-ripple controller adjusts the size of a ripple command value, which indicates the ripple current that is to be input to a converter circuit, so as to null the difference between the ripple voltages. Furthermore, using a ripple reference waveform having a DC level, the input-ripple controller generates a ripple current waveform so as to null the average value of a full-wave rectified waveform synchronized to the output of an inverter circuit, and outputs the generated ripple current waveform to an output calculator.

Abstract: The invention is a scheme for high power isolated full-bridge boost DC/DC converters to minimize the effect of in-rush current during start-up. A single pulse width modulation controller (PWM) is possible for the present invention for not only start-up but also normal boost modes. A primary circuit can have a clamping switch or at least two choke diodes. The choke diode can include “push-pull” and “L”-type configurations. A resistor can be used to dissipate energy clamped from the voltage spike. A startup circuit can be used to eliminate the in-rush current experienced during start-up. The proposed start-up schemes have been experimentally verified using a 1.6 kW, 12V/288 V prototype. Since the present invention eliminates the need to match characteristics of multiple controllers, it significantly reduces the cost associated with implementing this type of technology.

Abstract: The invention relates to a DC—DC converter and a power supply unit formed thereby, with which a DC input voltage (Vdc) may be converted into two DC output voltages (U1, Usb) via a resonant switched-mode power supply. Via a circuit stage (M1, M2), a control circuit (C) generates a first AC voltage (VAC), which is converted via two resonant circuits with different transmission behavior and two rectifiers (G1, Gsb) in frequency-dependent manner into DC output voltages (U1, Usb). To achieve a standby mode, in which the first DC output voltage (U1) is designed to be very low and hardly any power is drawn on the output side, a second, thinner auxiliary circuit stage (M3, M4) is provided, which is coupled to the resonant circuits via an inductor (L2). The current consumption of the circuit in standby mode may be reduced considerably by appropriate dimensioning.

Abstract: A method and system for detecting the negative sequence of three phase grid-connected inverter systems utilizes, for example, computer hardware and/or computer software to remove a direct current component from a direct-axis current feedback for a three phase current of the inverter system to yield a pure alternating current waveform signal. A first low pass filter eliminates high frequency noise from the alternating current waveform signal while passing a negative sequence signal. The filtered signal is rectified to an absolute value, and a second low pass filter flattens the rectified signal to an output signal that is indicative of the magnitude of the negative sequence current.

Abstract: An uninterruptible power supply is provided that is capable of turning off an AC switch made up of thyristors as quickly as possible by using a power converter. A power is supplied from the utility power supply 3 to the load 9 through the AC switch 1 made up of antiparallelly connected thyristors. Under this condition, in the event that the power failure detection means 12 detects a power outage, if the current detection means 11a detects a current of a positive polarity, the reference sinusoidal voltage generation circuit 11 generates the high synchronous sinusoidal voltage Vref2 which is higher, by the voltage difference command value &Dgr;V, than the synchronous sinusoidal voltage Vref1 in phase with the utility power supply.

Abstract: New techniques are presented for increased power handling capability for model railroad decoders and other attached electronics when space and cooling limitations exist. Additionally, novel usage of existing electronic voltage measurements permit an improvement in Overcurrent fault detection and recovery. These techniques allow new designs with improved reliability and load current capacity.

Abstract: An inverter device includes a series circuit having first and second switch units connected in series and a pulse signal generator for generating a pulse signal, and supplies an alternating voltage to a load by alternately driving the first and second switch units to be turned on and off in accordance with the pulse signal while a direct voltage is applied to the series circuit.

Abstract: An efficient and cost effective bidirectional DC/DC converter reduces switch voltage stress via accelerated commutation allowing use of a low-cost passive clamp circuit in boost mode. The converter includes a primary circuit, transformer and secondary circuit. The primary circuit takes the form of a “full bridge converter,” a “push-pull converter,” or an “L-type converter.”. The primary circuit may include a dissipator such as a snubber circuit or small buck converter. A secondary side of the transformer is momentarily shorted by the secondary circuit by, for example, turning on at least two switches in the secondary circuit simultaneously for a minimal calibratable period when a pair of primary circuit controllers turn off to protect the primary circuit switches from voltage spikes during switching conditions.

Abstract: A controller for motor/generators is proposed which allows reductions in ripple current generated by an inverter driving a power-generating motor/generator and a vehicle-driving motor/generator. The control device for motor/generators has a first inverter which supplies a control current to a first motor/generator used mainly as an electrical motor, a second inverter which supplies a control current to a second motor/generator used mainly as a generator, a first PWM signal generating circuit which drives the switching elements of the first inverter based on a first carrier signal, a second PWM signal generating circuit which drives the switching elements of the second inverter based on a second carrier signal which has the same period of the first carrier signal.

Abstract: A phase control circuit which can stabilize voltage control when used in a switching regulator, and a switching regulator using such a phase control circuit are provided. A switching circuit for generating a first and a second output signals having opposite polarities based on a clock signal, is provided. A PWM latch circuit, reset by a reset signal, for generating a third and a fourth output signals which have phases controlled with respect to the first and the second output signals respectively by a set signal produced based on a control signal and come to have opposite polarities, is provided. A delay circuit for delaying the rising of each of the first through the fourth output signals before outputting each of the first through the fourth output signals is provided for each output signal.

Abstract: The voltage converter circuit has first and second input terminals, and first and second output nodes, and comprises: a first power switch connected between the first input terminal and the first output node; a second power switch connected between the first output node and the second input terminal; a first delay circuit having first and second terminals connected between the first input terminal and a control terminal of the first power switch; and a second delay circuit having first and second terminals connected between the first output terminal and a control terminal of the second power switch. Each delay circuit detects a variation in the voltage supplied on the respective first terminal and detects an operating condition of the respective power switch on the second terminal, and supplies to the control terminal of the respective power switch a switching on delay signal.

Abstract: A power supply including an inverter receiving a DC input signal from a DC input source (11). The inverter is comprised of two half bridges (S1A, S2A and S1B, S2B). Each inverter is driven by a signal source (13A, 13B), which outputs an AC signal. The output from each inverter is input to a first stage harmonic filter. The power supply includes an output circuit that includes first and second rectifiers (D1, D2) arranged about a point so that if the inverter attempts to drive the point beyond a predetermined first and second voltage, the respective rectifier conducts in order to return at least one of power and current to the DC input source. The output from the first harmonic filter (L1A, C1; L1B, C1) is output to a second harmonic filter (L2, C2) and is then output from the power supply.

Abstract: An asymmetrical full bridge DC-to-DC converter comprises an asymmetrical full bridge circuit which includes main switches and auxiliary switches, a capacitor connected in series to the branch circuit of the auxiliary switches, and a transformer having a primary winding and a secondary winding. The primary winding of transformer is connected to the common point of each leg of the full bridge. A rectification circuit is connected at the secondary winding of the transformer to obtain dc voltage output. In operation, an asymmetrical control method is applied for these main switches and auxiliary switches. Main switches and auxiliary switches turn on and turn off compensatively. A linear control characteristic of output voltage to switching duty cycle and an optimal reset of the transformer core is achieved by this invention.

Abstract: This invention is an efficient and cost effective bi-directional DC/DC converter that can effectively reduce the switch voltage stress (such as a semiconductor) with an accelerated commutation circuit, and thus allowing a low-cost passive clamp circuit to be used. Specifically, the invention is a method and system to accelerate commutation for passive-clamped isolated boost converters, which can also be a boost mode in a bi-directional DC/DC converter. A primary circuit has a snubber comprising a diode, a capacitor and an energy dissipater (such as a resistor or small buck converter). The primary circuit can be a “full bridge converter” or a “push-pull converter” or an “L-type converter” configuration. The commutation of the present invention protects the primary circuit switches from voltage spikes during switching conditions.

Abstract: The present invention discloses a power conversion apparatus comprising a control circuit for generating a switching signal at the timing allowing soft-switching to be achieved, and free from any occurrence of ripple. The power conversion apparatus includes a first main switch (Q1) and a second main switch (Q2) which are connected in series with each other. One of the ends of the first main switch is connected with the positive side of a DC power supply, and one of the ends of the second main switch is connected to the negative side of the DC power supply. A diode (D1, D2) is connected in parallel with each of the main switches so as to become reverse biased with respect to the DC power supply. A main-switch snubber capacitor (C1, C2) is connected in parallel with each of the main switches. A load is connected with the junction between the pair of main switches, and the main switches are controllably switched according a switching signal from a control circuit to generate an output.

Abstract: The present invention relates a current zero crossing detecting circuit including a PWM driving half bridge circuit, which generates an output signal (OUT) and a signal synchronous with the high impedance condition of said PWM driving half bridge circuit. Said inventive circuit has the characteristic of comprising detecting means (DFLIP, COMP) synchronous with said signal synchronous with the high impedance condition of said PWM driving half bridge circuit and said output signal (OUT), and said detecting means generating a direction signal (DIR_COR) showing the current direction flowing in said pulse width modulation circuit.

Abstract: The invention in the simplest form is an improved transformerless 3 phase power inverter topology and control method for power distribution systems. This 3 phase power inverter system provides the necessary output voltage and current waveform regulation, harmonic distortion rejection, very low output impedance, and ultra low DC offset of the output AC power, even when exposed to a high magnitude of the non-linear, single phase, or the unbalanced loading.

Abstract: A switching power supply is provided in two stages with the primary of the power transformer being in the first stage and the secondary in the second stage. The first stage includes an EMI filter connected to the input of a rectifier. The output of the rectifier is connected to a self oscillating, half-bridge, resonant inverter operating in open loop with the primary of the transformer to provide isolation from the power source. Feed-forward control is used to compensate for line variations, providing very small output voltage variation compared with input voltage variation. In the second stage, the secondary of the transformer provides an input to post regulator circuitry including a PWM control circuit to regulate the output current using the error signal representing the differences between the current sensed and the desired value.

Abstract: An uninterruptable power supply includes a rechargeable battery, having a positive terminal and a negative terminal, and a transformer. The transformer includes a battery side transformer winding having a first terminal, a second terminal and a third terminal; a load side transformer winding inductively coupled to the battery side transformer winding via a core; and a power supply side transformer winding that is inductively coupled to the battery side transformer winding via the core. An inverter bridge circuit couples the positive terminal of the battery to the first terminal of the battery side transformer winding and couples the negative terminal of the battery to the second terminal and the third terminal of the battery side transformer winding.

Abstract: When an over-current is detected as flowing in semiconductor devices of a power converter by a Hall CT (current transformer), an abnormality detection unit outputs an abnormality signal. If the abnormality signal is output from the abnormality detection unit, a gate breaking unit of a gate driving unit outputs a gate breaking signal to stop the power converter. At the same time, a gate ON unit maintains the gate signal of the semiconductor device that has become abnormal in the ON state and, after the current in the semiconductor device has become smaller than a specified value, the gate signal of the semiconductor device is rendered OFF by a gate constriction device. By this operation, the current flowing in the semiconductor device may be reduced prior to any gate breaking operation occurring.

Abstract: The present invention discloses an active clamp forward converter that reduces the charging voltage of clamp capacitors as well as the voltage applied to switching elements, making it possible to reduce the on loss of the switching elements while also enabling the size of the capacitance elements to be reduced. The active clamp forward converter comprises first and second FETs which respectively connects first and second ends of a primary coil of the transformer to positive and negative terminals of a direct current power supply, and third and fourth FETs which respectively connects the first and second ends to the negative and positive terminals of a direct current power supply via capacitors, wherein the pair of first and second FETs and the pair of third and fourth FETs are alternately switched on and off sandwiched about a period when both are off.

Abstract: A soft-switched full-bridge pulse-width modulated (“FB PWM”) converter includes a coupled inductor provides ZVS conditions over a wide range of input voltages and output loads. Further, the FB PWM converter of the present invention requires neither a large leakage inductance in the transformer, nor an external inductor, to achieve ZVS.

Abstract: In a driving apparatus of a power semiconductor element for conducting or interrupting a main current, first resistance variable for changing a first resistance according to a control voltage, and second resistance variable for changing a second resistance according to a voltage between a first and a second terminal are provided, and either one of a voltage of a control power supply or a voltage between the first and the second terminal is voltage-divided by the first resistance and the second resistance, and the divided voltage is applied to a control gate terminal at the time of conducting or interrupting the main current.

Abstract: The voltage converter circuit has first and second input terminals, and first and second output nodes, and comprises: a first power switch connected between the first input terminal and the first output node; a second power switch connected between the first output node and the second input terminal; a first delay circuit having first and second terminals connected between the first input terminal and a control terminal of the first power switch; and a second delay circuit having first and second terminals connected between the first output terminal and a control terminal of the second power switch. Each delay circuit detects a variation in the voltage supplied on the respective first terminal and detects an operating condition of the respective power switch on the second terminal, and supplies to the control terminal of the respective power switch a switching on delay signal.

Abstract: A switching device having a first and a second electronic switch connected in a half-bridge configuration and each having a control terminal for receiving a switching signal alternatively having a turn-on value and a turn-off value for taking the first and second electronic switches to an on state and to an off state, respectively; the switching device includes, for each switch, means for detecting the state of the switch and means for keeping the switching signal at the turn-off value for one of the electronic switches when the detected state of the other electronic switch is the on state.

Abstract: A voltage converter circuit with a self-oscillating half-bridge configuration has a first and a second input terminal, and a first and a second output terminal, and including: a first power switch coupled between the first input terminal and the first output terminal, a second power switch coupled between the first output terminal and the second input terminal, a first voltage sensor having a first and a second sensing terminals coupled between the first input terminal and a control terminal of the first power switch, and a second voltage sensor having a first and a second sensing terminals coupled between the first output terminal and a control terminal of the second power switch. Each voltage sensor detects a voltage variation supplied on its respective first sensing terminal and generates on the respective second sensing terminal an activation potential for the respective power switch.

Abstract: An inverter circuit includes a pair of switching devices coupled in series across high and low sides of a direct current bus. An output line is coupled between the devices for conducting controlled alternating current power produced by timed switching of the devices. A flyback diode is electrically coupled a in parallel with each switching device and is physically positioned adjacent to the opposite switching device in the pair. Conducting paths between each diode and the associated switching device are preferably physically positioned adjacent to conducting paths between the switching devices and the output line. The placement of the elements cancels or reduces parasitic inductance during switching. Three similar arrangements may be provided in parallel in a three phase inverter. The inverter may be incorporated into a power substrate including a rectifying circuit for converting alternating current power to direct current power to be applied to the bus.