Abstract: A switched-mode power supply unit includes a mains input connecting the power supply to a primary supply voltage; an input circuit including a shared electrical path connected to the mains input and including a first mains filter, a first electrical path, connected in series with the shared electrical path, including a second mains filter, a second electrical path connected in series with the shared electrical path and connected in parallel with the first electrical path, and a first switching element that opens the first electrical path; a supply output that provides a filtered primary supply voltage; a switched-mode converter coupled to the supply output that converts the filtered primary supply voltage to a secondary supply voltage; and a control circuit that selectively switches the power supply unit to a first mode of operation with a high power output or a second mode of operation with a reduced power output.

Abstract: There is provided a filter for receiving a rectangular or stepped source voltage to be filtered and for providing an output voltage, the filter including means arranged to determine the output voltage in dependence on the frequency components of the source voltage within the filter passband, and independent of output current drawn.

Abstract: Phaseback DC choke includes a common core, a first coil formed about the common core, and a second coil formed about the common core in parallel opposing configuration relative the first coil. A DC circuit including a Phaseback DC choke is also provided.

Abstract: The invention provides a switching power supply device such that the occurrence of noise is reduced by jitter control of a switching frequency. The switching power supply device includes a switching power supply device main body wherein a predetermined output direct current voltage is obtained by switching an input alternating current voltage using a switching element, a switching control unit that controls the switching frequency in accordance with a feedback voltage that indicates the difference between an output set voltage and the output direct current voltage, a jitter control unit that applies jitter to the switching frequency, and a jitter amplitude control unit that changes jitter amplitude caused by the jitter control unit in accordance with the feedback voltage.

Abstract: A power electronic converter (30)is for use in high voltage direct current power transmission and reactive power compensation, the power electronic converter (30) including three phase elements (32) defining a star connection (36) and a converter unit (34) including first and second DC terminals (50,52) for connection in use to a DC network (56) and three AC terminals (54), the converter unit (34) including a plurality of switching elements (70,74) controllable in use to facilitate power conversion between the AC and DC networks (44,56), the power electronic converter (30) further including a third DC terminal (78) connected between the first and second DC terminals (50,52), the third DC terminal (78) being connected to a common junction (40) of the star connection (36) to define an auxiliary connection (82), the auxiliary connection (82) including at least one dump resistor (84) connected between the common junction (40) and the third DC terminal (78), wherein the switching elements (70,74) of the converter

Abstract: A power factor correction apparatus is applied to an alternating-current voltage apparatus and a rear end circuit. The power factor correction apparatus includes a power factor correction unit, a control unit, and a ripple detecting unit. The power factor correction unit is electrically connected to the rear end circuit and the alternating-current voltage apparatus. The control unit is electrically connected to the power factor correction unit. The ripple detecting unit is electrically connected to the rear end circuit, the power factor correction unit, and the control unit. The control unit is informed by the ripple detecting unit to control the power factor correction unit to adjust the power factor after the ripple of the signal outputted from the power factor correction unit is detected by the ripple detecting unit.

Abstract: A compensating system for a power system includes a compensator including semiconductor switch means, which compensator has phase legs which on a first side of the compensator defines AC inputs for connection to a respective phase of the power system. The phase legs are connected in wye connection at a second side of the compensator, which wye connection has a neutral point. A filter arrangement at a first side thereof is connected to the neutral point of the wye connection and at a second side is connected to the AC inputs to thereby form a circuit with the compensator. The filter arrangement is arranged such that the circuit acts essentially as an open circuit for positive sequence currents or voltages and negative sequence currents or voltages, and as a closed circuit for zero-sequence currents.

Abstract: A multiple inverter with neutral line inductor and an active power filter system are disclosed. In the disclosure, the multiple inverter comprises at least two inverter units connected in parallel, the midpoint of the direct current bus in each inverter unit is connected to the neutral line N through the respective neutral line inductor. The multiple inverter can suppress the ripple produced by the neutral line current without increasing the direct current bus capacitor.

Abstract: In one aspect, reduced power consumption and/or circuit area of a discrete time analog signal processing module is achieved in an approach that makes use of entirely, or largely, passive charge sharing circuitry, which may include configurable (e.g., after fabrication, at runtime) multiplicative scaling stages that do not require active devices in the signal path. In some examples, multiplicative coefficients are represented digitally, and are transformed to configure the reconfigurable circuitry to achieve a linear relationship between a desired coefficient and a degree of charge transfer. In some examples, multiple successive charge sharing phases are used to achieve a desired multiplicative effect that provides a large dynamic range of coefficients without requiring a commensurate range of sizes of capacitive elements. The scaling circuits can be combined to form configurable time domain or frequency domain filters.

Abstract: A noise filter is assembled to an electric power conversion device and has a metal housing casing and two capacitors connected to an external terminal of the device through which an electric power conversion circuit is connected to an external device. The two capacitors, the housing casing and the external terminal make a current loop. A magnetic flux of an alternating magnetic field generated in a part of the electric power conversion circuit penetrates in a first area and a second area formed in the current loop. A first induced noise current is induced in the current loop when the magnetic flux of the generated magnetic field penetrates in the first area. A second induced noise current is induced in the current loop when the magnetic flux penetrates in the second area so that the first induced noise current flows in a reverse direction to the second induced noise current.

Abstract: In a power converter, a housing is grounded. A power converter circuit is installed in the housing and configured to perform power conversion of input power into output power. An external terminal is electrically connected to the power converter circuit for connection of an external device to the power converter circuit. A first capacitor has first and second electrodes. The first electrode of the first capacitor is connected to the external terminal, and the second electrode thereof is connected to the housing. A second capacitor has first and second electrodes. The first electrode of the second capacitor is connected to the external terminal, and the second electrode thereof is connected to the housing. The first capacitor, the external terminal, the second capacitor, and the housing is arranged to provide a conductive loop.

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

Abstract: A power conversion device has a power module that switches the ON/OFF state of a switching element and converts and outputs input power, a metal housing that houses the power module, and a conductive member connected to the housing. The conductive member is connected to the housing at a position having a length of n?/4 from the open end. More specifically, “n” is an odd number of 1 or greater, “?” is the wavelength of noise generated by switching the switching element ON or OFF.

Abstract: A control method is used in a power factor corrector. Firstly, a current command signal from a computing circuit is received. Then, the current command signal is compared with an input signal of the power conversion circuit, so that a current error signal is generated. If the power factor corrector is operated in a transition interval between the first mode and the second mode, an addition operation is performed on the unadjusted current error signal, a feedforward signal and the adjusted current error signal, thereby generating a current control signal. A switch control signal is generated according to the current control signal. A switching element of a power conversion circuit is controlled according to the switch control signal. Consequently, the harmonic distortion of the input current is inhibited.

Abstract: A controller for controlling a power converter is described. The controller includes an input configured to receive at least one grid feedback signal, a filter, and an output. The filter is configured to receive the at least one grid feedback signal and generate an output signal that does not deviate by more than a predefined amount from the at least one grid feedback signal. The output is configured to provide a voltage command signal to the power converter that is based at least partially on the output signal.

Abstract: Various enhancements to grid-interactive inverters in accordance with embodiments of the invention are disclosed. One embodiment includes input terminals configured to receive a direct current, output terminals configured to provide an alternating output current to the utility grid, a controller, an output current sensor, and a DC-AC inverter stage comprising a plurality of switches controlled by control signals generated by the controller. In addition, the controller is configured to: generate control signals that cause the switches in the DC-AC inverter stage to switch a direct current in a bidirectional manner; measure the alternating output current; perform frequency decomposition of the output current; and generate control signals that cause the switches in the DC-AC inverter stage to switch current in a way that the magnitude of a plurality of unwanted current components is subtracted from the resulting output current.

Abstract: Processes, machines, and articles of manufacture that may management power conversion as provided. This may include circuit topology or management that serves to improve power conversion efficiency from a DC waveform to an AC waveform. This circuit topology or management may include considering and managing the voltage across a DC-link capacitive bus and the phase angle output of an AC waveform in order to influence or improve power conversion characteristics or efficiency.

Abstract: Systems and methods for suppressing resonances in power converters are provided. A power converter (100) includes an input stage (101) configured to receive alternating current (AC), an output stage (102) configured to output alternating current (AC), a first direct current (DC) bus (106) coupling the input stage (101) to the output stage (102), a second DC bus (108) coupling the input stage (101) to the output stage (102), a first capacitor leg (110) coupling the first DC bus (106) to the second DC bus (108) and a second capacitor leg (112) coupling the first DC bus (106) to the second DC bus (108). The first DC bus (106), the second DC bus (108), the first capacitor leg (110), and the second capacitor leg (112) form a current loop (130) having an effective inductance, and at least one resistor (140,142) configured to suppress a resonance of the power converter (100), wherein the resonance is based at least in part on the effective inductance of the current loop.

Abstract: An electronic apparatus is removed from a power supply apparatus and that can be certified by detecting a secondary-side transformer coil by a no-load detecting unit. The no-load detecting unit is configured to turn off an output switch unit and a power factor correction and pulse width modulation controller. An intermittent driving unit is configured to drive a start unit once a pre-determined time. The start unit is configured to drive the power factor correction and pulse width modulation controller. A load detecting unit is configured to detect that the electronic apparatus is connected to the power supply apparatus. The load detecting unit is configured to drive the intermittent driving unit. The intermittent driving unit is configured to drive the start unit. The start unit is configured to drive the power factor correction and pulse width modulation controller.

Abstract: The invention relates to an active filter device for a power supply comprising a source having a source of current iS and a voltage VE, a power converter presenting an input inductor L, a power switch T controlled by a chopper signal and delivering an output voltage VS, and a load, the device being characterized in that it includes an active filter converter (10) for generating at its output a compensation current minus harmonics of the source current due to the chopping, in response to an input signal representative of the chopping of the power converter.

Abstract: A power conversion apparatus, comprising: a power conversion circuit comprising an AC source; a power conversion unit with DC terminals and AC terminals; a filter inductor unit including first and second terminals, the first terminals of the filter inductor unit being connected to the AC source, the second terminals of the filter inductor unit being connected to the AC terminals of the power conversion unit; a common mode noise suppression circuit comprising a capacitive impedance network including first and second terminals; an impedance balancing network including first and second terminals; the second terminals of the capacitive impedance network are connected to the first terminals of the impedance balancing network, the first terminals of the capacitive impedance network are connected to the first terminals of the filter inductor unit, and the second terminals of the impedance balancing network are connected to the DC terminals of the power conversion unit.

Abstract: A controller for a load drive system which can reduce a ripple current which flows in a smoothing capacitor even when an inverter is PWM controlled with a two-phase modulation includes a converter for changing an output voltage of a DC power supply, an inverter for transforming a DC voltage outputted from the converter into a three-phase AC voltage to be applied onto a load and a smoothing capacitor provided in parallel between the converter and the inverter includes an inverter controller for PWM controlling the inverter with a two-phase modulation and a converter controller for PWM controlling the converter.

Abstract: A converter arrangement has at least one AC voltage connection, at which an alternating current can be fed in or drawn, and at least one DC voltage connection, at which a direct current can be fed in or drawn. The converter arrangement contains at least two series circuits connected in parallel. The external connections of the series circuits form the DC voltage connections of the converter arrangement. Each of the series circuits is connected in parallel and contains in each case at least two submodules connected in series, each of the submodules containing at least two switches and a capacitor. An energy store is to be connected to the capacitor of at least one of the submodules, wherein a filter is connected electrically between the capacitor and the energy store.

Abstract: An inverter and an active power filter system have been disclosed in the invention, so that the application range of the inverter under the occasions of different capacitor requirement can be widened, the cost can be decreased, and the efficiency can be improved. The technical scheme is: an auxiliary capacitor module can be added on the traditional inverter structure and connected in parallel selectively with the capacitor in the inverter. In a system without connecting an external auxiliary capacitor module, the value of capacitance can be designed to be smaller to satisfy the application under normal occasions. If the device operates under the occasions having large harmonic current or having large neutral line current, the ripple current on the capacitor will be larger so that large capacitance will be required to satisfy the life requirement, therefore, the problem can be solved by a method of installing an auxiliary capacitor module.

Abstract: An embodiment common mode noise reduction apparatus comprises a common mode choke, a balance inductor, a first capacitor and a second capacitor. The common mode choke is placed between an input dc source and a primary side network of an isolated power converter. The balance inductor is coupled between an upper terminal of a primary winding of the isolated power converter and a negative terminal of the input dc source. The first capacitor is coupled between the upper terminal of a primary side of a transformer and an upper terminal of a secondary side of the transformer of the isolated power converter. The second capacitor is coupled between a lower terminal of the primary side of the transformer and a lower terminal of the secondary side of the transformer of the isolated power converter.

Abstract: Provided is a maximum power point (MPP) tracker for a PV cell inverter, and a PV cell inverter. The MPP tracker decouples output power oscillations from the input power generation and extracts maximum available power from the PV cell. The PV cell inverter uses the MPP tracker and generates a sinusoidal output current from the MPP tracker output. The sinusoidal output current may be fed to a power distribution grid. The PV cell inverter may use a pulse width modulation technique to cancel harmonics in the sinusoidal output current. The circuits use a minimum number of components and avoid use of large electrolytic capacitors.

Abstract: A multiple inverter and an active power filter system are disclosed in the invention, said multiple inverter can decrease the volume and harmonics, increase the efficiency and decrease the cost, and can be applied to various occasions. The technical scheme is: the filter assembly in the multiple inverter is installed at the output inductor of the multiple inverter for filtering the harmonics.

Abstract: The invention provides a digital active EMI filter that removes, minimizes, or reduces unwanted interference (i.e., EMI noise) generated by a power circuit such as, for example, a power converter. Digital active filtering includes digital sampling of the incident noise signal amplitude and frequency, discrete time conversion of the EMI noise source, processing (e.g., inverting) the digital signal, and then constructing an analog output signal (i.e., an EMI compensation signal) which is injected to the input of the power circuit. A digital EMI filter as described herein may be used in both differential-mode and common-mode configurations, and overcomes limitations of passive and active analog EMI filters.

Abstract: The present invention relates to a near zero current-ripple inversion circuit including top and bottom cells, a transformer (T1) comprising primary windings (P1, P2) and a secondary winding (S1), and at least one middle cell connected in series between the top and bottom cells. The top cell comprises two capacitors (C1, C2) and a switch (Q1) each connecting to the middle cell, and an inductor (Lr1) and the primary winding (P1) connected in series between the capacitor (C1) and switch (Q1), wherein the switch (Q1) is connected to the capacitors (C1, C2) respectively. The bottom cell comprises a capacitor (C3) and a switch (Q2) each connecting to the middle cell, and an inductor (Lr2) and the primary winding (P2) connected in series between the capacitor (C3) and switch (Q2), wherein the primary winding (P2) is connected to the middle cell, and the capacitor (C3) and switch (Q2) are connected.

Abstract: A duty ratio/voltage conversion circuit that converts the duty ratio of an input signal into voltage level and outputs the voltage level includes: an input terminal to which the input signal is input; a first CR integrating circuit that integrates the input signal; a load resistor a first end of which is connected to an output point of the first CR integrating circuit, and a second end of which is grounded; and an output terminal connected to the load resistor. The first CR integrating circuit includes a first pathway that has a first resistor, and a second pathway in which a phase inversion portion, a second resistor and a first capacitor are connected in series, and is a parallel circuit in which first and second ends of the first pathway are connected to first and second ends, respectively, of the second pathway.

Abstract: First windings of a first common mode transformer and second windings of a second common mode transformer are connected in series via connection lines. The windings are connected to an AC power supply via connection lines. The first windings are connected to a three-phase motor via connection lines, a converter, and an inverter. High-frequency leakage currents flowing in the connection lines are detected as a common mode voltage by a winding for common mode voltage detection. An output voltage is inputted via a filter to a voltage amplifier unit that amplifies the output voltage, and the amplified voltage is applied to a winding via a capacitor in substantially a same direction as a direction of the common mode voltage. As a result, leakage currents are reduced by induced voltages on the windings.

Abstract: A power line filter including a socket, a housing, a plurality of filter elements and a ground inductor is disclosed. The socket includes at least one power pin and a ground pin. The housing is assembled with the socket, and includes a first receptacle and a second receptacle. The opening direction of the first receptacle is opposite to the opening direction of the second receptacle. The plurality of filter elements is disposed in the first receptacle. At least one of the filter elements is electrically connected to the power pin. The ground inductor is disposed in the second receptacle and electrically connected to the ground pin.

Abstract: An inverter with galvanic separation including a resonant converter and an upstream mounted boost chopper is intended to provide galvanic separation in the context of a variable input and output voltage as it exists in photovoltaic systems, with the efficiency being intended to be optimized over the entire input voltage range. This is achieved in that a boost chopper or a buck chopper is mounted upstream of the resonant converter.

Abstract: A method of assembling a testing apparatus for a full-power converter assembly includes coupling an electric power supply apparatus to an electric power grid. The method also includes coupling a direct current (DC) generation apparatus to the electric power supply apparatus. The method further includes coupling an electric power grid simulation device to the DC generation apparatus. The method also includes coupling a full-power converter assembly test connection to the electric power grid simulation device.

Abstract: A noise reduction unit includes a plurality of cores each having formed therein a through hole, a plurality of wires connected to a noise source and each wound around the corresponding core through the through hole, and a core supporting member that supports the plurality of cores. The core supporting member supports the plurality of cores in such a manner that the plurality of cores is disposed parallel to each other along a through direction of the through holes and spaced apart from each other with a predetermined gap in the through direction.

Abstract: A low-loss compact and a method for producing the compact are provided. A method for producing a compact by using coated soft magnetic powder that includes coated soft magnetic particles constituted by soft magnetic particles and insulating coatings coating outer peripheries of the soft magnetic particles includes a raw material preparation step and an irradiation step. In the raw material preparation step, a raw compact is prepared by press-forming coated soft magnetic powder. In the irradiation step, part of a surface of the raw compact is irradiated with a laser. Irradiating a part of a surface of a raw compact with laser increases the number of disrupted portions of conductive portions where constituent materials of the soft magnetic particles at the surface of the raw compact have become conductive to each other, and the loss of the compact can be decreased.

Abstract: The present invention relates to an electrical device for charging accumulator means (5), said electrical device comprising: a motor (6) connected to an external mains (11); an inverter (2) connected to the phases of said motor (6); and switching means (4) integrated into the inverter (2), said switching means (4) being configured to permit said motor (6) to be supplied and to permit the accumulator means (5) to be charged by the inverter (2). According to the invention, said electrical device further includes, for each phase of said motor (6), an RLC low-pass filter (18) connected, on the one hand, to the mid-point (16) of the phase of said motor (6) and, on the other hand, to ground.

Abstract: A power conversion apparatus is disclosed in the present application. The power conversion apparatus comprises: a power converter comprising an energy-storage magnetic component, and a filter comprising an inductor component and a two-port network connected the energy-storage magnetic component and the inductor component, wherein a series resonance is formed by the two-port network and a mutual inductance which is formed by a coupling between the energy-storage magnetic component and the inductor component.

Abstract: A switching power supply transmits power between a single front end including electromagnetic interference filtering and power factor correction circuits to an output end at a high voltage and high frequency from which any desired DC voltage or waveform may be readily and directly derived with high efficiency in order to reduce size and weight of components including transformers at the output end and allow greater variety of connection wiring of reduced weight and volume to be used. The high frequency is limited at the low frequency end by the frequency at which significant power can be transferred through, for example, a ferrite core or other transformer of sufficiently low volume to accommodate closely spaced loads or power converters and at the high frequency end by the wavelength in the connection wiring such that 1/10 wavelength is greater than one thousand feet.

Abstract: A pulse width modulation controller and method for output ripple reduction of a jittering frequency switching power supply detect the current of a power switch of the switching power supply to generate a current sense signal, and adjust the gain or the level of the current sense signal according to the switching frequency of the power switch to adjust the on time of the power switch, to reduce the output ripple of the switching power supply caused by the jittering frequency of the switching power supply.

Abstract: Embodiments of the invention can provide systems, methods, and apparatus for converting direct current (DC) power to alternating current (AC) power. According to one embodiment, a system for converting DC power to AC power can be provided. The system can include a DC power source that provides a first DC power signal to a converter. Coupled to the converter can be a controller for transforming the first DC power signal into a plurality of AC power signals. The controller can also phase shift at least one of the plurality of AC power signals and combine the phase shifted AC power signal with at least one of the other of the plurality of AC power signals to provide a second DC power signal. The controller can also convert the second DC power signal to an AC power signal.

Abstract: An electrical power system includes an alternating current (AC) power source configured to output an AC signal, a single phase pulse-width modulated (PWM) rectifier coupled to the AC power source and to an electrical load; a DC link capacitor coupled in parallel to the load and the PWM rectifier; and an active ripple energy storage circuit. The active ripple energy storage circuit has a first terminal, a second terminal and a third terminal, the active ripple energy storage circuit being coupled in parallel to the electrical load, the PWM rectifier and the DC link capacitor via the first terminal and the second terminal, the third terminal being coupled to the second terminal, the active ripple energy storage circuit being configured to selectively absorb and discharge at least part of the ripple energy.

Abstract: Power conversion systems and control techniques are presented in which a bus transient control component bypasses selected phases of a rectifier during a protective mode of operation to reduce common mode voltages or currents.

Abstract: A ripple compensation apparatus comprises a ripple detection unit to detect a ripple on a dual DC bus, a waveform generation unit to generate a modulated waveform based on a base waveform and the detected ripple, and a multi-phase control signal generation unit to receive the modulated waveform and to generate at least one pulse width modulated control signal based on the modulated waveform.

Abstract: In one aspect the invention relates to an electrical circuit for use with a generator having an output port, the circuit to modify one of an electric current or voltage from the generator. The circuit includes a rectifier to convert the alternating current from the generator to direct current, the rectifier having a first port and a second port, the rectifier first port in communication with the output port of the generator; and a direct current to alternating current inverter to convert the direct current from the rectifier to alternating current, the inverter having a first port and a second port, the first port of the inverter in communication with the second port of the rectifier. In one embodiment, the generator is a linear alternator positioned within an energy converting apparatus comprising a Stirling engine having a piston such that motion of the piston drives the linear alternator.

Abstract: A method for controlling an alternating current (AC) output of a photovoltaic (PV) device, and an AC PV device are introduced herein. The method includes: receiving solar radiant energy by using a PV cell array and then converting the solar radiant energy into a direct current (DC) energy output; and selecting an arrangement and combination sequence of the PV cells by using a control module, to vary a voltage according to a timing (frequency), so that a sine-like wave output is obtained at an output terminal.

Abstract: Systems and methods described herein provide for high speed power factor correction which can overcome or substantially alleviate the problems associated with changes in the operating conditions of a load or other transient events. The present technology senses the present state conditions of a signal to quickly and accurately determine the presence of an overtone component within the signal. The expected value of the overtone component is then determined based on the sensed state of the signal. Power factor correction is then performed to suppress the overtone utilizing a control signal formed based on the expected value of the overtone. By performing power factor correction based on the expected value, the present technology can provide high speed power factor correction which is not limited by the delay introduced by an adaptive feedback loop.

Abstract: A method of controlling at least one voltage converter having a plurality of cells in series, comprising an AC part and a DC part, characterized in that the AC input voltage (Vei) of each cell is determined directly by the use of a high speed current control loop relating to the AC part and a lower speed voltage control loop relating to the cells, the method including choosing the following voltage control law: ? i = C i 2 ? ( 2 R pi ? C i ? Z i + ? ? t ? Z i ? ? _ ? ? ref - K 1 ? Zi - K 2 ? Zi ? sign ? ( E Zi ) ) where: K1zi and K2zi are positive adjustment gains; Ci is the continuous capacitance of the capacitor Ci of each cell; Rpi is the losses associated with each cell; Zi—ref is the reference value of Zi=(UDCi)2, UDCi; being the direct voltage across the capacitor Ci; and EZi is such that EZi=Zi?Zi—ref.

Abstract: A power converter includes first and second circuit modules, a first capacitor, a second diode and a control module. The first circuit module includes a switching element in parallel with a first diode. The second circuit module includes a first inductor and the first circuit module. The inductor is in series with the first circuit module. The first capacitor is in parallel with the second circuit module. The second diode includes a first terminal and a second terminal, where the first terminal is in series with the second circuit module and the first capacitor, and the second terminal is coupled to a second power terminal. The control module varies one or more of the first capacitor and the first inductor based on at least one of a current of a load circuit or an input voltage. A resonating waveform is generated by a resonant circuit of the second circuit and is used by the control module to turn off the switching element under zero-current and zero-voltage conditions.

Abstract: The present invention includes: an inverter 1 configured to perform pulse wide modulation on an output from a DC power source 5; a first capacitor pair 41 provided at an input side of the inverter and including two capacitors serially connected to form a neutral point; a second capacitor pair 42 provided at an output side of the inverter and including two capacitors serially connected to form a neutral point; a bypass path g for a leakage current formed by connecting the neutral point of the first capacitor pair and the neutral point of the second capacitor pair to each other; at least one common mode choke coil 3 provided between the first capacitor pair and the second capacitor pair and configured to suppress a common mode current generated in the inverter; and an output filter 2 configured to convert a voltage, which is outputted from the inverter and subjected to the pulse wide modulation, into a voltage in a sine wave form.