Abstract: A switch mode power supply and method for operating the power supply and to the use of the same, wherein the switch mode power supply comprises a control for controlling a control element and is connected to a DC link of the converter, the switch mode power supply comprises a startup-delay such that control of the switch element is blocked until a predetermined start delay duration (T) has lapsed, where the start delay duration (T) is longer than the time span between DC link charging.

Abstract: Apparatus and system for powering an isolated gate driver. In one embodiment, the apparatus comprises a gate driver power supply unit (PSU), coupled to a transistor and to an isolated gate driver that couples control signals to the transistor, for (i) harnessing energy from commutation action across the transistor, and (ii) using the harnessed energy to power the isolated gate driver.

Abstract: A system interconnecting facility is connected to a power system, and includes a plurality of power converters connected to the power system, a plurality of transformers provided between the power system and the power converters, a plurality of switches provided between the transformers and the power converters, and a controller that controls the opening and closing of the switch. The controller outputs, to the switches, open and close commands in so that the number of closed switches is out of a closed switch number range where a harmonic voltage of the system interconnecting facility increases, based on a harmonic voltage containing rate characteristic that is a relation between the number of closed switches and a harmonic voltage containing rate of the system interconnecting facility. The system interconnecting facility is capable of suppressing a harmonic voltage even if a circuit structure differs depending on a situation.

Abstract: A wind power generation system including a doubly fed induction generator (DFIG) of a wind turbine is presented. The DFIG includes a rotor and a stator, a rotor-side conversion unit coupled to the rotor, a direct current (DC) link, and at least one line-side conversion unit coupled to the rotor-side conversion unit via the DC link and coupled to the stator of the DFIG. The at least one line-side conversion unit includes exactly one first converter, high frequency transformers, and second converters, where each of the second converters is coupled to the first converter via a respective high frequency transformer, and inverters, where each of the inverters is coupled to a respective second converter and includes an alternative current (AC) phase terminal.

Abstract: The disclosure relates to a contactor having electronic coil control for a magnet coil, the operation of keeping the pull-in power of the magnet coil constant being formed by current clocking, and having a safety-related output assembly of a programmable logic controller for the fault diagnosis of the contactor, the safety-related output assembly determining the flow of current flowing into the contactor and detecting a fault if a limit value is undershot and switching off. In the contactor disclosed herein, a connectable base load is integrated in the contactor.

Abstract: A network feedback unit feeds electrical energy from a voltage intermediate circuit into a three-phase network. The network feedback unit has: a buck converter unit having first and second buck converters, the first buck and second buck converters being connected in parallel with the input side of each electrically coupled to the voltage intermediate circuit; an inverter, with the input side electrically coupled to an output of the buck converter unit and the output side electrically coupled to the three-phase network; at least one filter capacitor arranged at the output of the buck converter unit or at the output of the inverter; and a controller unit to drive the first and second buck converter depending on a filter capacitor current such that the first and second buck converter contribute in equal parts to an output current of the buck converter unit.

Abstract: This bidirectional power conversion system for a single-phase electric load is intended to be connected to a continuous supply bus delivering a single supply voltage and deliver to the load an alternating output voltage substantially in a cradle form. It includes a set of intertwined converters able to jointly deliver a control voltage whose phase shift of its fundamental component with respect to the output voltage is intended to control the transfer of power between converters and the load, said converters being controlled in such a way that the amplitude of the average value of the control voltage corresponds to the amplitude of the alternating output voltage and in such a way that said control voltage has amplitudes capable of reducing the fluctuations of a current flowing between the voltage converters and the load.

Abstract: Techniques are described for ripple detection and cancellation in switching voltage regulator circuits. For example, in a switching voltage converter, a voltage is up-converted or down-converted by switching high side and low side switches and passed through a low-pass filter for averaging. While the act of switching can result in conversion of the voltage with good efficiency, it also typically generates ripples on the output voltage, which can be undesirable in some applications. Embodiments use the switching voltage, the output voltage, and a feed-forward loop to generate a current cancellation signal to have particular gain, timing, and polarity that effectively emulates the complement of the inductor ripple current. The cancellation current signal can be injected into the output node, such that the cancellation current signal sums with the inductor ripple current at the output node, thereby at least partially cancelling the effect of the inductor ripple current.

Abstract: A dual-output generator is configured to output two or more waveforms at different frequencies. In particular, the dual-output generator is configured to provide low-frequency output, which may be suitable for ultrasonic surgical instruments, and a high-frequency output, which may be suitable for electrosurgical instruments, while reducing the amplitude of all remaining frequencies other than the two selected low and high frequencies to about zero.

Abstract: A control system of a low voltage DC-DC converter is provided. The system includes a low voltage DC-DC converter unit that has a power semiconductor element and converts power supplied from a high voltage battery of a vehicle into power of low voltage. A switching frequency change unit changes a switching frequency of the power semiconductor element and a microcomputer generates a final PWM signal based on an input voltage value input from the high voltage battery and an output voltage value of the switching frequency change unit to apply a maximum duty command voltage to a PWM controller. The PWM controller applies PWM voltage to the power semiconductor element to thus operate the power semiconductor element at less than a maximum duty based on the maximum duty command voltage applied from the microcomputer.

Abstract: A motor controller and methods for operating a motor are described herein. The motor controller includes a high-frequency (HF) inverter having a direct current (DC) input stage and an alternating current (AC) output stage, the HF inverter operable at a switching frequency to generate a three-phase output having a fundamental frequency. The motor controller also includes a differential mode (DM) filter coupled in series with the output stage of the HF inverter and having a resonant frequency less than 10% of the switching frequency, the DM filter configured to reduce harmonic components of the three-phase output and generate a first filtered output. The motor controller further includes a common mode (CM) filter coupled in series with the DM filter, the CM filter configured to filter the first filtered output to generate a second filtered output having a reduced CM voltage to operate the electric motor with a reduced bearing current.

Abstract: Virtual oscillator control systems, devices, and techniques are provided. One example device includes a processor configured to implement a virtual oscillator circuit and output an oscillating waveform based on the virtual oscillator circuit and power electronics operatively coupled to the processor and configured to convert, based on the oscillating waveform, direct current (DC) electricity to alternating current (AC) electricity. The processor may be further configured to extract, from the virtual oscillator circuit, a virtual current based on an output current of the AC electricity, and output the oscillating waveform further based on an input voltage of the DC electricity.

Abstract: An electric vehicle control device includes: a main transformer to convert AC voltage input to an input winding thereof from an AC power source, and output converted AC voltage from each of a plurality of output windings; a plurality of converter main circuits, each connected to one of a plurality of secondary windings included in the output windings, to convert AC voltage output from connected secondary windings into DC voltage; and a plurality of converter controllers, each targeting for control one of the converter main circuits, to control by pulse width modulation the control-target converter main circuit, by comparing a signal wave and carrier wave. Each of the converter controllers determines a phase angle correction amount of the signal wave and/or the carrier wave, in response to operating state of a load supplied power through a predetermined output winding among the output windings.

Abstract: An alternating current step-down circuit comprises an AC input, a DC output, an AC output, a full-bridge rectification and filtering circuit, a flyback step-down circuit, a DC-DC step-down unit and an inverting unit. The AC input is connected with an input of the full-bridge rectification and filtering circuit; an output of the full-bridge rectification and filtering circuit is connected with an input of the flyback step-down circuit and an input of the DC-DC step-down unit, respectively; an output of the flyback step-down circuit is connected with the DC output, the input of the DC-DC step-down unit and an input of the inverting unit, respectively; an output of the DC-DC step-down unit is connected with the input of the inverting unit; and an output of the inverting unit is connected with the AC output.

Abstract: A power supply includes: a power converter that converts an input voltage by switching at a switch and supplies an output voltage and an output current to an output terminal connected to a load; a current detector that detects the output current or a current that changes with the output current and outputs a current detection signal whose voltage value changes with the output current; a signal corrector that inputs and corrects the current detection signal and generates and outputs a corrected current detection signal whose voltage value corresponds to the value of the output current; a matching circuit that inputs the corrected current detection signal and outputs to a balanced terminal; and a controller that inputs the corrected current detection signal and a balanced voltage signal generated at the balanced terminal and controls switching operations of the switch to reduce a difference between the two signals.

Abstract: A display interface circuit includes a first transistor and a second transistor electrically connecting in series between a first motherboard power and a display power. A first body diode of the first transistor has a current direction opposite a second body diode of the second transistor. When a display device powers up but a motherboard powers downs, a first control circuit turns on the first transistor and a second control circuit turns off the second transistor such that a current does not leak from the display power toward the first motherboard power due to the second body diode. When the display device powers down but the motherboard powers up, the first control circuit turns off the first transistor and the second control circuit turns off the second transistor such that the first motherboard power is not outputted to a video display interface due to the first body diode.

Abstract: A system and method for operating a drive system coupleable to one or more DC and AC electrical ports is disclosed. The drive system includes a DC link, at least one DC-DC converter, at least one DC-AC converter, a DC link capacitor, and a control system configured to control operation of one or more of the at least one DC-DC converter and the at least one DC-AC converter relative to one another based on operational parameters thereof. In controlling operation of one or more of the at least one DC-DC converter and the at least one DC-AC converter, the control system controls at least one of a switching frequency of the at least one DC-DC converter, a switching frequency of the at least one DC-AC converter, a DC-DC converter carrier signal phase, a DC-AC converter carrier signal phase, and a duty cycle of the at least one DC-DC converter.

Abstract: Duties of control for DC/AC and DC/DC conversion units are determined by considering electric influences of a filter circuit, a capacitor connected to a DC bus, and a DC reactor for an output voltage command value for supplying an AC voltage to a load. The DC/DC conversion unit is controlled to convert a DC voltage into a DC bus voltage waveform alternately having a period of a pulsating current waveform corresponding to the absolute value of the AC voltage and a period of the DC voltage as a pulsating current minimum value. The DC/AC conversion unit is controlled to perform step-down operation during the period of the DC voltage and thus perform conversion into a waveform of the absolute value of the AC voltage corresponding to the period of the DC voltage, and also to perform polarity inversion per one pulsating current cycle.

Abstract: A periodic disturbance suppressing control apparatus is designed to estimate and correct an inverse model of a transfer characteristic of a real system successively even in case of large condition change in the real system, and to realize a stable control system. A periodic disturbance of an object to be suppressed is outputted as a sensed periodic disturbance ISdn, ISqn of a direct current component. A difference between a signal obtained by multiplication of the sensed periodic disturbance ISdn, ISqn with a multiplier using a reciprocal Qn of a transfer characteristic, and a signal obtained by adding only a detection delay to a periodic disturbance suppressing command I*dn, I*qn, to estimate the periodic disturbance dI^dn, dI^qn. Thee periodic disturbance suppressing command is calculated by calculating a deviation between the estimated periodic disturbance dI^dn, dI^qn.

Abstract: Disclosed is a phase-shifted square wave modulation technique for single-phase and three-phase IM2DC applications in HVDC/MVDC systems. A square wave based modulation waveform is applied to each cell of IM2DC and compared to the phase-shifted carrier waveforms to generate device gate signals. As a result, a higher equivalent switching frequency can be achieved, and square wave based arm and AC link waveforms will be generated. In addition, power flow of IM2DC can be controlled by a phase shift angle of the square modulation waveforms between HVS and LVS. The converter cell capacitors can be reduced in size because they are only required to smooth high switching frequency ripple components. In addition, lower TDR can be achieved due to the higher power transferring capability of square waves.

Abstract: The present invention is concerned with pre-magnetizing a Modular Multilevel power Converters connected transformer in order to moderate inrush currents upon connecting the transformer to an electric grid. The invention takes advantage of the high amount of stored energy in MMC converters as compared to other converter types. This stored energy is used to pre-magnetize the converter-connected transformer, therefore no additional or dedicated pre-magnetizing hardware is required in addition to the charging hardware provided to charge the converter capacitors. As the transformer pre-magnetizing takes place subsequent to the converter charging, the converter charging circuit is not used to, and therefore does not need to be designed to, directly magnetize the transformer.

Abstract: A multiphase power supply includes several constant ON-time (COT) DC-DC converter integrated circuits (ICs), with each COT DC-DC converter IC providing an output voltage of a phase of the multiphase power supply. The COT DC-DC converter ICs are sequentially turned ON one after another in interleaved fashion. A COT DC-DC converter IC receives a control signal at a take pin and, in response, turns ON its output switch. The COT DC-DC converter IC generates another control signal at a pass pin. The next COT DC-DC converter IC turns ON its output switch in response to receiving the other control signal from the previous COT DC-DC converter IC.

Abstract: A power converter includes a transformation circuit configured to transform a rectified voltage, and a converter control unit configured to control a switching element of the transformation circuit. The converter control unit calculates a current command value based on a line voltage or the phase voltage, calculates a current deviation between the current command value and the reactor current, and calculates a switching command value from the current deviation. The converter control unit includes a plurality of integrators for the respective different phase angles of a power supply voltage. The integrator corresponding to a power supply phase angle is caused to accumulate the current deviation, and the integrator corresponding to a phase angle that is advanced by a set delay phase from the power supply phase angle is caused to output the control amount. A switching signal is generated with use of the control amount and the switching command value.

Abstract: We describe a power conditioning unit with maximum power point tracking (MPPT) for a dc power source, in particular a photovoltaic panel. A power injection control block has a sense input coupled to an energy storage capacitor on a dc link and controls a dc-to-ac converter to control the injected mains power. The power injection control block tracks the maximum power point by measuring a signal on the dc link which depends on the power drawn from the dc power source, and thus there is no need to measure the dc voltage and current from the dc source. In embodiments the signal is a ripple voltage level and the power injection control block controls an amplitude of an ac current output such that an amount of power transferred to the grid mains is dependent on an amplitude of a sinusoidal voltage component on the energy storage capacitor.

Abstract: A multi-mode controller applied to a power converter includes a detection range generation module and a gate signal generation unit. The detection range generation module is used for generating a comparison voltage according to a reference current, and generating a detection signal according to the comparison voltage and a first reference voltage. When the detection signal is disabled by a zero-crossing signal, the gate signal generation unit generates a gate control signal corresponding to a quasi-resonant mode of the power converter according to the zero-crossing signal; and when the detection signal is disabled by a continuous-conduction mode signal generated by the detection range generation module according to the comparison voltage and a second reference voltage, the gate signal generation unit generates the gate control signal corresponding to a continuous-conduction mode of the power converter according to the continuous-conduction mode signal.

Abstract: Disclosed herein are a method and an apparatus for generating a random PWM voltage reference signal for driving an inverter, which can more simply generate random position PWM (RPPWM) in which a position of an active vector is changed to achieve the same effect as when a switching frequency is changed.

Abstract: A circuit (4) for establishing a desired impedance value for a radio antenna (5) comprising a transistor (3) having an input (8) and an output terminal (6), and a printed radio frequency transformer comprising a first (1) and a second inductor (2), both inductors (1, 2) having a coupling factor value, and having a first and a second terminal (11, 12; 21, 22). The first terminal (11) of the first inductor (1) is adapted for connecting a radio antenna (5). The input terminal (8) of the transistor (3) is connected to the second terminal (12) of the first inductor (1), and the output terminal (6) of the transistor (3) is connected to the first terminal (21) of the second inductor (2), so that the desired impedance value (Z2) at the second terminal (22) of the second inductor (2) is determined by the inductance value of the second inductor (2).

Abstract: A gas turbine power generation system is configured by a gas turbine, a main power generator which is coupled to a rotor of the gas turbine through a rotation shaft, a rotation rectifier which converts a three-phase AC current into a DC current and transfers the DC current to a field magnet winding wire of the main power generator, an AC exciter which is configured by an armature winding wire, a d-axis field magnet winding wire, and a q-axis field magnet winding wire, and transfers the three-phase AC current generated at the armature winding wire to the rotation rectifier, an excitation device which drives the AC exciter at the time of start-up of the main power generator, and an excitation power supply which supplies a current to the excitation device.

Abstract: Controlling power consumption of a voltage regulator in a computer system that includes computer memory and the voltage regulator is configured to provide regulated source voltage to the computer memory includes: receiving, by a voltage regulator controller, memory margin statistics of the computer memory, the memory margin statistics including data describing operational tolerance of the computer memory to source voltage signal variations; and adjusting, by the voltage regulator controller, one or more operating characteristics of the voltage regulator in dependence upon the memory margin statistics.

Abstract: A system and method of controlling an electric motor using a motor drive controller are provided. The motor drive controller includes a rectifier configured to convert an AC input voltage to a DC voltage, a DC bus electrically coupled to the rectifier, an inverter electrically coupled to the DC bus and configured to generate an AC voltage to drive the electric motor, and a control unit. The control unit includes a sign calculation module configured to determine a polarity of each phase of a reference current command and a compensation module configured to generate a voltage compensation command signal using one of the determined polarities of the reference current command and a measured current, and one of a measurement of DC bus voltage and a constant DC bus voltage value, the voltage compensation signal compensating the drive controller to neutralize a deadtime effect.

Abstract: A matrix convertor includes a power convertor and a controller. The power convertor is disposed between a power system and a rotating electric machine, and includes a plurality of bidirectional switches. The controller is configured to control an exciting current flowing from the power convertor to the rotating electric machine so as to control a power factor on a side of the power system.

Abstract: Embodiments of the present invention relate to an a method, apparatus and computer program product for controlling the operation of a drive unit comprising a plurality of switching modules arranged to receive a DC electricity supply and generate an AC electricity supply for driving a load from the received DC electricity supply, the AC electricity supply being generated by the switching of the plurality of switching modules between a conducting state and a non-conducting state. The method comprises receiving one or more characteristics associated with each of the switching modules, comparing, for each switching module of the plurality of switching modules, a characteristic of the switching module with an equivalent characteristic associated with one or more other switching modules of the plurality of switching modules, and controlling a time period during which one or more of the plurality of switching modules are in the conducting state in accordance with a result of the comparison.

Abstract: A power stage for a DC-to-DC voltage converter includes a voltage input, a high-side n-channel transistor, a high-side p-channel transistor, and a low-side n-channel transistor. The voltage input is couplable to a supply voltage. The drain terminal of the high-side n-channel transistor is coupled to the voltage input and the source terminal is coupled to a first node that is couplable to an output stage of the DC-to-DC converter. The source terminal of the high-side p-channel transistor is coupled to the voltage input and the drain terminal is coupled to the first node. The drain terminal of the low-side n-channel transistor is coupled to the first node and the source terminal is coupled to a ground.

Abstract: Current metering for transitioning to low power operation in switching regulators is disclosed. In an exemplary embodiment, a method is provided that includes generating pulse width modulated charging cycles that enable current to flow to an inductor to adjust an output voltage, and detecting a skipped charging cycle. The method also includes determining whether a number of charging cycles are skipped over a time interval that begins when the skipped charging cycle is detected. The method also includes transitioning to a low power operating mode if it determined that the number of charging cycles have been skipped over the selected time interval. During the low power operating mode pulse frequency modulated charging cycles are generated that enable the current to flow to the inductor to generate the output voltage.

Abstract: Active droop current sharing among power supply units may regulate output currents of power supply units supplying shared current to a common load. The regulation may employ a combination of droop control and active current control. The shared current may be regulated such that each power supply unit provides a substantially equal share of the total current supplied. A current difference between two power supplies may be regulated to be within a desired maximum threshold for current difference.

Abstract: A self-balanced modulation method and a closed-loop magnetic flux rebalancing control method for parallel multilevel inverters. The combination of the two methods provides for balancing of the magnetic flux of the inter-cell transformers (ICTs) of the parallel multilevel inverters without deteriorating the quality of the output voltage. In various embodiments a parallel multi-level inverter modulator is provide including a multi-channel comparator to generate a multiplexed digitized ideal waveform for a parallel multi-level inverter and a finite state machine (FSM) module coupled to the parallel multi-channel comparator, the FSM module to receive the multiplexed digitized ideal waveform and to generate a pulse width modulated gate-drive signal for each switching device of the parallel multi-level inverter. The system and method provides for optimization of the output voltage spectrum without influence the magnetic balancing.

Abstract: Systems and methods may provide for a transient response apparatus that includes a single stage conversion module having a power input, a power output, and a control input, and a compensation module including a feedback input. The compensation module may be coupled to the power input, the power output and the control input of the single stage conversion module. Additionally, a feedback module may be coupled to the power output of the single stage conversion module and the feedback input of the compensation module. In one example, the feedback module includes a loop controller having a plurality of programmable inputs and an error output, and a modulus unit coupled to the error output of the loop controller and the feedback input of the compensation module.

Abstract: According to one embodiment, there is provided a control device of a neutral-point-clamped power converter apparatus including a converter configured to convert current which were obtained by passing a d-axis current and a q-axis current of a rotating coordinate system through a filter having a time constant which is greater than an inverse number of a fundamental wave frequency of a three-phase currents, to three-phase currents, and a controller configured to calculate, based on the three-phase currents converted, a zero-phase voltage instruction value for controlling voltages into which a DC input voltage is divided at a neutral point, as an instruction value which is superimposed on three-phase voltage instruction values.

Abstract: A control unit is for a bridge circuit. The control unit may include a signal generator configured to generate first and second periodic drive signals for the bridge circuit, and determine a switch-on duration of the first and second periodic drive signals based upon a first digital data value having a first resolution. The control unit may include a controller configured to receive a second digital data value having a second resolution. The second resolution may be greater than the first resolution. The controller may be configured to generate the first digital data value so that, over periods of the first and second periodic drive signals, the first digital data value corresponds to an average of the second digital data value.

Abstract: Provided is a power conversion device including: a conversion device for each phase which converts DC voltage inputted from a DC power supply, to voltage having an AC waveform to be outputted to each phase with respect to a neutral point of three-phase AC; and a control unit which controls these conversion devices. Each conversion device includes: a first converter which has a DC/DC converter including an isolation transformer, and a capacitor, and which converts the inputted DC voltage to voltage containing a pulsating DC voltage waveform corresponding to the absolute value of the AC waveform to be outputted; and a second converter which is provided at a stage subsequent to the first converter and has a full-bridge inverter, and which inverts the polarity of the voltage containing the pulsating DC voltage waveform, per one cycle, thereby converting the voltage to voltage having the AC waveform.

Abstract: A power circuit includes: first and second switching circuits coupled in parallel between an input terminal and an output terminal; a control signal generator that performs an ON/OFF control of the first and second switching circuits individually and generates a first control signal and a second control signal having different phases; a frequency converter that converts a frequency of the first control signal after converting a frequency of the second control signal; and a phase shifter that shifts the phase of the second control signal when a first interrupt is introduced as the first control signal is turned ON after the frequency converter has converted the frequency of the second control signal.

Abstract: An isolated power control device that includes an auxiliary isolated power circuit and a voltage level identification unit is provided. The auxiliary isolated power circuit includes a transformer module, a control module, and a switch module. The transformer module includes a primary side and a secondary side. The control module generates a switch control signal according to a primary side remote on/off control signal. The switch module is conducted according to the switch control signal to transmit an input auxiliary power signal to the primary side of the transformer module such that the auxiliary isolated power circuit generates a target voltage signal having a plurality of voltage levels. The voltage level identification unit receives the target voltage signal to output a secondary side remote on-off control signal to control a main isolated power device.

Abstract: A wind power conversion system includes plural first converting circuits and a second converting circuit. The plural first converting circuits perform a power converting task, and include respective first generator-side terminals and respective first network-side terminals. The first generator-side terminals are electrically connected with a wind power generator. The first network-side terminals are electrically connected with corresponding secondary windings of an isolating transformer. The second converting circuit includes plural second generator-side terminals and a second network-side terminal. The second network-side terminal is electrically connected with the corresponding secondary winding of plural secondary windings of the isolating transformer. The second generator-side terminals are serially connected with the corresponding first generator-side terminals of the first converting circuits.

Abstract: A method for detecting a phase imbalance of an electrical component in a machine due to an actual fault is provided. The method includes receiving electrical parameter values associated with a plurality of phases of an electrical component, detecting a phase imbalance in the plurality of phases, calculating an imbalance ratio of the plurality of phases, applying a plurality of conditions to the imbalance ratio and to the received input vector, the plurality of conditions being associated with an actual fault in the machine, and determining whether the detected phase imbalance is due to a controls induced imbalance in the machine or due to the actual fault in the electrical component of the machine when at least one of the plurality of conditions is met.

Abstract: A multi-stage quick charging system is proposed. The system uses an intermediate power battery as voltage supporting point so that a converter having a fraction of the output voltage may control the entire power flow towards or from the battery of a vehicle or an electrical power device. The intermediate battery comprises several stages in series, associated with respective small chargers allowing a management of the charge balancing of the stages of the intermediate battery, since the chargers may be controlled in order to separately vary the contribution of each stage.

Abstract: A control method for reducing second-order ripple is adapted to reduce second-order ripple on an input side of a DC-DC conversion device, wherein the input side of the DC-DC conversion device is coupled to a preceding voltage supply device, and an output side of the DC-DC conversion device is coupled to a DC-AC transforming device, characterized in that a voltage control device for controlling the preceding voltage supply device is designed according to a transfer function, and the transfer function is adjusted and controlled with an output voltage of the DC-DC conversion device and an amplitude voltage of pulse width modulation to reduce second-order ripple of an input voltage input to the input side of the DC-DC conversion device, thereby dispensing the need to increase circuits or increase capacitance of components and cutting costs.

Abstract: A power converter fixes, in one cycle of an alternating-current voltage output command, a gate pulse signal to always output a direct-current input positive side terminal voltage value of an inverter circuit in a period X1 centering on a phase angle ?1 for higher potential, fixes a gate pulse signal to always output a direct-current input negative side terminal voltage value of the inverter circuit in a period X2 centering on a phase angle ?2 for lower potential, and outputs a gate pulse signal in which a ratio of a period Y1, which is obtained by excluding the periods X1 and X2 from a period between the phase angle ?1 and the phase angle ?2, and the first period X1, and a ratio of a period Y2, which is obtained by excluding the periods X1 and X2 from a period between the phase angle ?2 and a phase angle ?1+360 [deg].

Abstract: A method of controlling an inverter includes receiving a target waveform for output voltage of an inverter phase, calculating a phase bias for an inverter phase using the target waveform, biasing the target waveform using the phase bias, and generating a switching device command signal by comparing the biased target waveform to a carrier waveform. The switching device command signal has a switching patter that reduces midpoint current in an inverter input lead and common mode voltage in an inverter output lead.

Abstract: A method controls a motor using pulse width modulation (PWM). The method involves measuring the PWM frequency; determining the carrier frequency of a set radio transmitter; and matching the PWM frequency to the carrier frequency of the radio transmitter in such a manner that an integer multiple of the PWM frequency corresponds to the carrier frequency or an integer multiple of the PWM frequency lies in the middle between two carrier frequencies.

Abstract: A circulating current and oscillating current suppressing method and parallel inverter driver system are disclosed. Each inverter driver outputs a suppressing three-phase current to a motor and has an entity inductance device and a virtual inductance device. The virtual inductance device receives and sums the suppressing three-phase current of the inverter drivers, and generates a compensated three-phase current according to the suppressing three-phase currents, an impedance of the motor and an ideal impedance value generated by a virtual inductance unit and the entity inductance device. Consequently, the oscillating current of the transition three-phase current outputted from a switch device of the inverter driver can be reduced.