Abstract: The present document relates to a power converter comprising an inductor, a first stage, and a second stage. The first stage may be coupled between an input of the power converter and the inductor, and the first stage may comprise a first flying capacitor. The second stage may be coupled between the inductor and an output of the power converter, and the second stage may comprise a second flying capacitor. A second terminal of the first flying capacitor may be connected to a first terminal of the inductor, and a first terminal of the second flying capacitor may be connected to a second terminal of the inductor.

Abstract: A current sourced control topology is provided for an AC motor controller that eliminates many of the problems associated with prior art motor controllers that use voltage source inverter (VSI) technologies. By controlling the output of AC current sources such as synchronously controlled down converters to directly drive each motor phase, significant efficiency gains and a reduction in electromagnetic interference is achievable.

Abstract: A DC-DC converter includes an inductor, a rectifier module, a first bridge arm topology and a second bridge arm topology and a third bridge arm topology in parallel as well as a capacitor, wherein the first bridge arm topology includes a first switching tube and a fourth switching tube in series, the second bridge arm topology includes a second switching tube and a fifth switching tube in series, and the third bridge arm topology includes a third switching tube and a sixth switching tube in series; the inductor has one end connected to a coupling point formed by connecting the first switching tube and the fourth switching tube in series, and the other end connected to a coupling point formed by connecting the second switching tube and the fifth switching tube in series.

Abstract: A method for controlling a dual-fed induction generator (DFIG) connected to a power grid in response to a high-voltage grid event includes receiving, via a controller, a frequency signal of the power grid. The method also includes filtering the frequency signal via a filtering assembly so as to determine whether certain types of grid conditions are present in the power grid. The filtering assembly includes a first filter connected in parallel with a second filter. The first filter has a bandwidth that is greater than the second filter. Further, the method also includes comparing output signals of the first and second filters of the filtering assembly to one or more frequency thresholds. Moreover, the method includes controlling the DFIG based on the comparison.

Abstract: A system and method of operating a pumped storage power plant using a double fed induction machine with a frequency converter in a rotor circuit is disclosed. A current target value for the rotor current frequency is determined based on a target power to be transmitted between an electrical grid and the double fed induction machine depending on measured actual operating variables. A current inadmissible synchronous deadband is determined depending on variables characterizing a current state of the pumped storage power plant. The synchronous deadband is determined by a permissible minimum required rotor current frequency or speed difference of the rotor speed from the synchronous speed for the stationary operation. The converter is controlled to generate voltages and currents with the current target value of the rotor current frequency if the current target value of the rotor current frequency or speed does not fall in the current inadmissible synchronous deadband.

Abstract: Power supplies together with related over voltage protection methods and apparatuses. A power supply has a transformer including a primary winding and an auxiliary winding. A power switch is coupled to the primary winding and a sensing resistor coupled between the power switch and a grounding line. A multi-function terminal of a controller is coupled to the sensing resistor. A diode and a first resistor is coupled between the auxiliary winding and the multi-function terminal.

Abstract: An illustrative device includes a first silicon-controlled rectifier (SCR) and a second silicon-controlled rectifier (SCR) connected in anti-parallel and a first commutation module, which includes a first voltage source, a first diode, and a first self-commutating semiconductor switch. The device also includes a second commutation module including a second voltage source, a second diode, and a second self-commutating semiconductor switch. The first voltage source, the first diode, and the first self-commutating semiconductor switch of the first commutation module are connected in series. The second voltage source, the second diode, and the second self-commutating semiconductor switch of the second commutation module are connected in series. The first SCR, the second SCR, the first commutation module, and the second commutation module are connected in parallel. The commutation modules are configured to apply reverse bias voltages to the first and second SCRs to turn off the SCRs.

Abstract: A power converter includes first to fourth terminals, a transformer including primary and secondary windings, an inverter connected between the first and second terminals and the primary winding, a converter connected between fifth and sixth terminals, and a controller. The converter includes first to eighth switch circuits each including a diode and a switch connected in parallel. When a voltage between the fifth and sixth terminals has first polarity, the controller controls the first switch circuit to be in on-state during a first on-period and controls the fifth switch circuit to be in on-state during a second on-period completely including the first on-period. When the voltage between the fifth and sixth terminals has second polarity, the controller controls the second switch circuit to be in on-state during a third on-period and controls the sixth switch circuit to be in on-state during a fourth on-period completely including the third on-period.

Abstract: In a method for controlling a cycloconverter having six converter branches connected in series, in which converter branches electrical energy stores are provided, the energy transfer from a first three-line network into a second three-line network or vice versa is controlled according to energy demand criteria, energy supply criteria, and/or reactive power criteria for converter operation control. The amount of electrical energy stored in each converter branch or an electrical variable that characterizes the amount of electrical energy is controlled to a predetermined setpoint range for energy converter control.

Abstract: In a switching regulator, a control circuit includes a reference command value generation portion and an additional command value generation portion. The reference command value generation portion generates a reference command value based on a deviation of an output voltage from a predetermined command voltage. The additional command value generation portion generates an additional command value based on a difference between an outflow electric energy and an inflow electric energy. The outflow electric energy is a value reflecting a supply power from the capacitor to the load, and the inflow electric energy is a value reflecting a supply power from the reactor to the capacitor. The control circuit controls an operation ratio of a switching circuit based on the reference command value and the additional command value.

Abstract: A three phase step-up autotransformer construction is discussed herein. The passive 12-pulse AC-DC converter offers simplicity, high reliability and low cost solution to AC-DC power conversion. The autotransformer is a component of the passive 12-pulse AC-DC converter. The autotransformer converts three-phase AC power into six-phase AC power. With appropriate vector design, the autotransformer may be configured to draw a near sinusoidal 12-pulse current waveform from the three-phase voltage source. The six-phase output may be configured to drive a rectifier (non-linear) load.

Abstract: A circuit for turning OFF a thyristor. The circuit includes at least one first circuit element configured to provide a high reverse turn-OFF voltage to the thyristor gate for a predetermined period of time. Immediately following the predetermined period of time, at least one second circuit element provides a normal reverse turn-OFF voltage to the thyristor gate. The normal reverse turn-OFF voltage is substantially lower than the high reverse turn-OFF voltage.

Abstract: The present invention relates to nonlinear and time-variant signal processing, and, in particular, to methods, systems, and apparatus for adaptive filtering and control applicable to switching power supplies.

Abstract: Disclosed is a method for controlling a permanent magnet synchronous motor to maximize use of voltages of a battery by voltage phase control within weak magnetic flux area and to achieve compensation for a torque error through a torque compensator when driving the permanent magnet synchronous motor for hybrid vehicles. In particular, the method controls a permanent magnet synchronous motor so that voltage use can be maximized in a weak magnetic flux area by using voltage near maximum voltage through voltage phase control utilizing magnetic flux-based map data receiving a torque command and motor speed/batter output voltage as inputs and torque error can be compensated using a torque compensation filter when a motor constant is changed in the weak magnetic flux by a circumstance parameter, when the permanent magnet synchronous motor mounted in a hybrid vehicle and an electric vehicle is driven.

Abstract: A device for producing an alternating current output voltage from a high-frequency, square-wave input voltage comprising, high-frequency, square-wave input a matrix converter and a control system. The matrix converter comprises a plurality of electrical switches. The high-frequency input and the matrix converter are electrically connected to each other. The control system is connected to each switch of the matrix converter. The control system is electrically connected to the input of the matrix converter. The control system is configured to operate each electrical switch of the matrix converter converting a high-frequency, square-wave input voltage across the first input port of the matrix converter and the second input port of the matrix converter to an alternating current output voltage at the output of the matrix converter.

Abstract: A converter has converting groups with a first stage connected to input lines thereof and a second stage connected to output lines. The first and second stages have positive and negative branches that are connected together.

Abstract: A converter bridge arm suitable for high-voltage applications and an application system thereof. The converter bridge arm comprises an energy storage capacitor (C) and a plurality of reverse-conducting switches, and is formed by serial connection of an upper telescopic arm (Bu), a lower telescopic arm (Bd) and an inductor (Lb). The upper telescopic arm (Bu) and the lower telescopic arm (Bd) are respectively formed by cascading connection of a plurality of units. The converter bridge arm has a simple modular structure, is easy to control, reliable and convenient for starting a high-voltage circuit, has self-balancing voltage sharing effect, and can operate without a transformer and has the characteristic of power bidirectional flow, does not require high-voltage isolation auxiliary power supply, has the advantages of suitability for high-frequency operation and electromagnetic compatibility, and can remarkably reduce the dimension of a filter.

Abstract: A matrix converter control apparatus includes three AC switches each including a first and a second switching elements connected in series. The first and the second switching devices each: have a first terminal, a second terminal, and a gate terminal; pass a current between the first terminal and the second terminal when a first voltage which is a voltage of the gate terminal with reference to a voltage of the first terminal is higher than a threshold voltage; interrupt a current flowing from the second terminal to the first terminal when the first voltage is lower than the threshold voltage; and pass a current from the first terminal to the second terminal when the first voltage is lower than the threshold voltage and the voltage of the gate terminal is higher than the threshold voltage with reference to a voltage of the second terminal.

Abstract: Methods and apparatus provide for: a rectification circuit operating to convert a source of AC power into a final DC power source; a rectification filtering capacitance operating to at least partially smooth a voltage of the final DC power source, which exhibits a voltage sag and recovery characteristic in response to time-variant current drawn therefrom; a power amplification circuit drawing power from the final DC power source and producing an output signal, for driving a speaker, having audible characteristics influenced by the voltage sag and recovery characteristic of the final DC power source; and a control circuit operating to continuously vary, in response to user input, one or more parameters of the voltage sag and/or recovery characteristic of the final DC power source.

Abstract: A power supply includes a power source having at least one power source output, and a plurality of drivers connected to the at least one power source output. At least one of the plurality of drivers includes a bridge network having a first switch, a second switch and a bridge network output. The first switch is connected between the at least one power source output and the bridge network output. The second switch is connected between the bridge network output and a ground. The bridge network further includes at least one control input connected to the second switch. The bridge network is adapted to change a state of the first switch based on a state of the second switch.

Abstract: In an induction motor group control system, magnetic energy recovery switches (3) are connected in series to an induction motor (2) directly driven by a commercial power supply, and a plurality of induction motor control devices (10) enabling voltage control and reactive power control of the induction motor 2 are employed to control generation of reactive power so as to maximize a power factor of the entire plurality of AC loads including the induction motor or compensate variations in voltage of an AC power supply (1).

Abstract: A sensorless induction motor control device with a function of correcting a slip frequency wherein a slip frequency estimation unit estimates the slip frequency from at least one kind of current flowing through the motor. A voltage command value calculation unit calculates a D-phase voltage command value and a Q-phase voltage command value which are used for controlling a voltage applied to the motor using a Q-phase current command value calculated based on a difference between a speed estimation value, which is calculated using an estimation value of the slip frequency, and an externally supplied speed command value. An ideal voltage command value determination unit determines an ideal voltage command value using the speed command value and the Q-phase current command value. An actual voltage command value calculation unit calculates an actual voltage command value using the D-phase voltage command value and the Q-phase voltage command value.

Abstract: An electric power converter facilitates performing soft switching in the two-way electric-power-conversion operation thereof, and reducing the manufacturing costs thereof and the losses caused therein, The electric power converter includes a first switching device; a second switching device; a first series circuit including capacitor, a diode, the primary winding of transformer, and a third switching device; a second series circuit including a capacitor, a fourth switching device, the primary winding of transformer, and a diode; a third series circuit including a diode and the secondary winding of transformer; and a voltage clamping element connected in parallel to the primary winding of transformer. The first series circuit is connected in parallel to the first switching device, and the second series circuit is connected in parallel to second switching device. The third series circuit is connected between the DC output terminals.

Abstract: A sensorless controlling apparatus for controlling a brushless motor includes a speed calculator for calculating speed of a rotor ?, an angle calculator for calculating rotor angle ? at a predetermined time interval, and an angle controller for calculating correction angle ?? based on the current value of a d-axis current (d-axis current value id), thereby controlling the rotor angle ?. The angle calculator uses the correction angle ?? calculated by the angle controller, the speed ? calculated by the speed calculator, a predetermined time, and the rotor angle ? calculated by the angle calculator at a predetermined time to calculate the rotor angle at the predetermined time interval. Thus, the rotor angle ? calculated by the angle calculator is converged on the true angle of the rotor.

Abstract: Switching device for linking various electrical voltage levels in a motor vehicle, in which a drive voltage level has an electric drive machine which may be actuated by a power converter, and a drive energy accumulator which is associated with an intermediate circuit, and in which the drive voltage level is connected to a vehicle electrical system voltage level by an electrical converter. The electrical converter is designed as a coupling circuit which is connected at the drive side to at least one node point of a winding circuit of the electric drive machine and to a voltage potential relative to the intermediate circuit. The coupling circuit is connected at the vehicle electrical system side to the vehicle electrical system via a switching unit which has at least one non-diminishing, finite impedance.

Abstract: A remote battery charger, comprising a DC-to-DC converter, able to accept a first DC current with a voltage of less than 13 VDC and able to produce, from said first DC current, a second DC current of at least a 15 amps at a voltage of at least 13.5 VDC, provided an adequate first DC current level. Also, the charger includes a current acceptance reduction input, whereby when said input is activated said DC-to-DC converter reduces its acceptance of said first DC current.

Abstract: A matrix converter for converting a polyphase alternating current into a desired alternating output current includes at least two stages; a plurality of controllable bidirectional switches, converts m phases of the polyphase alternating current into alternating output current with n (n<m) phases of a load; and a controllable bidirectional switch controlling each phase of the polyphase alternating current in at least one stage of the converter.

Abstract: A control method for a PWM cyclo-converter is provided in which a voltage can be accurately generated even when a voltage command is small. In the PWM cyclo-converter, the turning on and off operations of two-way semiconductor switch are repeated at intervals of short time. As switching patterns, within the intervals of short time, a first terminal of output side terminals outputs in order a maximum potential phase P, an intermediate potential phase M and the maximum potential phase N, a second terminal of the output side terminals outputs in order the maximum potential phase P, the intermediate potential phase M, a minimum potential phase N, the intermediate potential phase M and the maximum potential phase P, and a third terminal of the output side terminals outputs in order the intermediate potential phase M, the minimum potential phase N and the intermediate potential phase M.

Abstract: A power converting apparatus and a power converting method for driving a high voltage AC motor at a variable speed. Conventional invertor systems cannot solve technical subjects such as energy conservation, resource conservation, miniaturization, efficiency promotion and voltage and current waveform distortion suppression for improvement in environment needed by the market, and cannot solve another technical subject of improvement in redundancy such that, upon failure, operation is performed with a normal part.

Abstract: A portable power unit is provided. A desired waveform signal indicative of a desired waveform having a desired frequency is generated. Switching control of a variable control bridge circuit is performed based on the desired waveform signal to cause the variable control bridge circuit to generate an alternating current output. A waveform of the alternating current output is detected to generate an output waveform signal indicative of the detected waveform of the alternating current output. A power factor is detected by comparing the desired waveform signal and the output waveform signal to generate a power factor signal indicative of the detected power factor. Voltage of the alternating current output is controlled based on the power factor signal.

Abstract: In a vehicle braking system, integral control and isolation valves are used to individually control the brake line pressure to each wheel brake and to provide pedal isolation for each brake channel. The system is operable on a single fluid or a separated fluid system with an integrated power source. Full proportional anti-lock braking and traction control is provided to each selected wheel independently. The system is applicable as a two, three or four channel base brake system.

Abstract: A power conversion apparatus comprises an inverter circuit for converting DC power into AC power which has a first frequency; a transformer connected to the inverter circuit. A cyclo converter circuit having a bidirectional switch controls a direction in which an electric current passes and converts the output from the transformer into AC power which has a second frequency. A switching signal generating circuit generates a switching signal for controlling the polarity of the bidirectional switch of the cyclo converter circuit in such a manner that the output voltage from the inverter circuit does not encounter a short circuit.

Abstract: A three-phase converter for polyphase induction motors has an input transformer with primary windings and at least two secondary windings associated with each primary winding, and controlled power semiconductors. Groups of power semiconductors are connected to the secondary windings such that the power semiconductors operate in series with the motor phases.

Abstract: A DC-to-AC electric power converting apparatus includes: an inverter circuit for converting DC electric power into AC electric power; a transformer connected to the inverter circuit; a cyclo-converter circuit for converting the frequency of the output from the transformer; a carrier signal generator for generating a carrier signal of a predetermined frequency; an inverter switching circuit for generating a signal for controlling the inverter circuit in synchronization with the carrier signal; a reference voltage signal generating circuit for generating a reference signal for the AC voltage to be transmitted from the cyclo-converter circuit; a first switching signal generating circuit for generating a switching signal in accordance with the reference voltage signal supplied from the reference voltage signal generating circuit and the carrier signal supplied from the carrier signal generator; and a cyclo-converter switching circuit for generating a signal for controlling the cyclo-converter circuit in accordanc

Abstract: A digitally-controlled cycloconverter converts a multiple-phase power signal of variable frequency into a single-phase or multiple-phase signal of a lower selected frequency. The cosinusoidal algorithm is utilized to determine the firing delay times, with the analog reference wave used in that algorithm being created from a digitized hardware table. The cosinusoidal algorithm is further simplified by defining the relationship between the analog reference wave and the cosinusoidal timing waves in terms of a two-part piecewise linear relationship which is incorporated into a digital algorithm. The digital algorithm is implemented on a system employing a high-power microprocessor having hardware multiplication and division capability, allowing the algorithm to be used with supply voltages having frequencies about those previously used for cycloconversion. The control logic involved with the firing of a series of thyristors is simplified by utilizing pulse transformers.

Abstract: An AC motor drive apparatus of this invention is constituted by an AC power source, a first circulating current type cycloconverter having an output terminal coupled to the AC power source, a phase-advanced capacitor coupled to an input terminal of the first cycloconverter, a second circulating current type cycloconverter having an input terminal coupled to the phase-advanced capacitor, and an AC motor coupled to an output terminal of the second cycloconverter. The first cycloconverter controls a current supplied from the AC power source to be a sine wave in the same phase as that of the power source voltage, so that a voltage crest value of the phase-advanced capacitor becomes substantially constant. The second cycloconverter supplies a sine wave current of a variable frequency to the AC motor.

Abstract: Three terminal, six and twelve pulse unrestricted frequency changing circuits are provided by inserting controllable bidirectional switching circuits between open star configured coils in multiple phase windings of isolation transformers. Where the switched winding are secondaries of the isolation transformer, interphase transformers are provided between each pair of three pulse circuit groups and additional interphase transformers are required between six pulse circuit groups to provide a three terminal output. Where the switched windings are primary windings of the isolation transformer, the secondary windings are electrically connected in series with each other to provide the three terminal output.

Abstract: A self-extinguishing element such as a gate turn-off thyristor (GTO) is used for each arm of the inverter. A capacitive load is connected to the output terminal of the inverter. In a region where the output frequency of the inverter is low, the self-extinguishing element is forcibly commutated. In a high-frequency region, where the output frequency of the inverter is higher than that in the low-frequency region, the capacitive load causes the self-extinguishing element to be load-commutated.

Abstract: A frequency converter is provided for a three-phase electric motor and has input connections for a multi-phase alternating current electric supply source, and output connections for connection to a three-phase electric motor. A SCR bridge including a plurality of SCRs interconnects the input connections and the output connections. A trigger circuit is connected to the SCR bridge for selective firing of the SCRs, in response to timing pulses generated upon zero crossing of the input means phases. Logic circuits interconnecting said timing pulse generators and the trigger circuits for effecting selective sequential firing of the SCRs at the zero crossings. Firing of said SCRs is respectively terminated by natural commutation. In one embodiment of the invention single phase current is converted to multiphase current.

Abstract: A three-phase matrix converter including switches having snubber circuits associated thereto, is provided with a common voltage clamp capacitor for limiting the voltage applied to the snubber capacitor, and energy is accumulated in the clamp capacitor which is controllably dissipated, in particular by providing energy to auxiliary elements of the overall system.

Abstract: A supply device connected to a 3-phase mains supply for an ozonizer comprising at least two capacitive discharge elements (7, 8). The device comprises two single-phase step-up voltage transformers (1, 2) having air gaps (5, 6) connected in a Scott circuit and connected between the 3-phase mains supply and said discharge elements (7, 8).

Abstract: Power is fed to a plurality of loads by a respective plurality of circulating current type cycloconverters connected to an ac power supply. A power compensating capacitor common to the cycloconverters is provided at the ac power receiving-end to deliver a leading reactive power to the ac power supply. Further, each cycloconverter is provided with means for delivering a circulating current and means for delivering a circulating current command value to the circulating current control means. A lagging reactive power corresponding to the leading reactive power by the power factor compensating capacitor is delivered to the ac power supply. The power factor compensating capacitor may be configured so that its capacity is variable by changing the number of stages connected. In addition, the circulating current command value may vary depending upon the peak value of the current flowing in each cycloconverter.

Abstract: A control system for a cycloconverter of the circulating current type produces an ac current of a variable frequency. The cycloconverter is configured to connect a power factor compensating capacitor at its receiving-end, thus to control a lagging reactive power due to a circulating current flowing in the cycloconverter so as to cancel a leading reactive power due to the power factor compensating capacitor. Such a control is carried out under the condition of an operation below the rated load. In contrast, under the condition of an operation above the rated load, a control is effected so that the circulating current flowing in the cycloconverter is substantially kept constant.

Abstract: A three phase voltage system, balanced and sinusoidal, is converted into another one, having the same properties, but with amplitude, frequency and phase changed, by means of sequential sampling of all input phases. The desired output system is synthetized through a matrix of electronic switches, which are operated sequentially by control pulses having a duration proportional to the instant value of a linear combination of sinusoidal waveforms and with a duty cycle modulated accordingly to the required output parameters.

Abstract: In an unrestricted frequency changer (UFC) the control pulses are generated by the intersection of a reference ramp of controllable slope and frequency with a succession of timing ramps characterizing the succession of phase voltages at the input of the UFC, whereby by increasing the slope and exceeding the peaks of the timing waves the sinusoidal shape of the output becomes trapezoidal and by increased slope increasingly close to a square-shaped wave, thus maximizing the output voltage at high frequency of operation.

Abstract: A high response motor controller is disclosed which operates directly from a multi-phase AC power line without a DC link. The controller directly converts power from a fixed frequency multi-phase input to a D.C. or variable frequency output current. The output frequency is not limited by the AC power line frequency and the switching frequency is independent of the AC power line frequency. Controlled switching devices are connected between the multi-phase power input line and the power output line. Analog input signals are compared with signals representative of actual motor currents to produce current error signals. These current error signals control the conduction state of the controlled switching output transistors by a two state modulation process.

Abstract: a multiphase AC current of one frequency is converted to a multiphase current of another frequency by a frequency changer having its output terminals terminated by a load having the impedance characteristics of a voltage source. In this arrangement the multiple phases of a practical AC current source such as a synchronous generator are connected directly to each load phase, even where the bidirectional switches of the UFC are arranged in pulse groups or a bridge configuration.

Abstract: A circulating current of a cycloconverter in each phase is distributed and controlled in such a way that a circulating current in a phase having a large absolute value of a load current is small, and the circulating current of a phase having a small absolute value of the load current is large. Therefore, the reactive power is so compensated that the sum of lagged reactive powers of the phases and advanced reactive power of a phase advancing capacitor cancel out each other.

Abstract: An ozonizer power feeding device comprising a multiphase power source having at least one terminal for each phase, a thyristor circuit coupled to the terminals of the power source and including at least two thyristors for each phase connected at one side thereof in an anti-parallel configuration to a respective terminal of the source, a transformer having at least one primary coil coupled to the other sides of the anti-parallel connected thyristors and a secondary coil adapted to be connected to an ozonizer for feeding power to the ozonizer, and a joint control unit coupled to each of the thyristors for controlling the conduction time thereof in dependence on the waveforms provided at the terminals of the source in order to derive a composite waveform applied to the transformer primary, wherein the composite waveform has a high frequency than that of any of the phases of the power source, thereby increasing ozone production which is proportional to the frequency of the applied power.

Abstract: The firing pulses to the nonload carrying bank only of the naturally commutated thyristor power circuit of a static power converter are retarded to reduce or eliminate the interbank circulating current. In one form of the invention, half wave rectified load current signals are summed with the output waveform reference signal applied to the positive and negative bank firing pulse generators in a sense to retard the pulses in the nonload carrying bank. In another form of the invention, the inversion end stops are used to generate the retarded firing pulses in the nonload carrying bank.