Abstract: An electric motor system includes a battery, an inverter, an electric motor, a zero-phase switching arm and a control unit. The inverter converts DC power output from the battery into three-phase AC power and outputs the three-phase AC power to the electric motor. A rotor of the electric motor rotates by the three-phase AC power output from the inverter. A neural point of the electric motor is connected to the zero-phase switching arm. A zero-phase current flowing through respective windings of the electric motor is adjusted by switching of the zero-phase switching arm. By this means, in the electric motor system, torque is generated at the rotor also using the zero-phase current as well as a three-phase AC current flowing through the respective windings.

Abstract: An electronic circuit arrangement for a fuel cell arrangement may include a first electrical voltage converter stage and a second electrical voltage converter stage. An electrical fuel cell voltage may be appliable to the first electrical voltage converter stage on an input side. The electrical fuel cell voltage may be convertible into a first electrical output voltage of the first electrical voltage converter stage via the first electrical voltage converter stage. The first electrical output voltage may be appliable to the second electrical voltage converter stage on an input side. The first electrical output voltage may be convertible into a second electrical output voltage of the second electrical voltage converter stage via the second electrical voltage converter stage. An electrical interconnection of the first electrical voltage converter stage and the second electrical voltage converter stage may be switchable between a first interconnection state and a second interconnection state.

Abstract: A power conversion circuit includes an input positive terminal, an input negative terminal, an output positive terminal, an output negative terminal, a first bridge arm, a second bridge arm, a transformer, a first resonant capacitor, a second resonant capacitor, a third resonant capacitor and a third resonant capacitor. The transformer includes a first winding, a second winding and a third winding. The plurality of switches in the first bridge arm and the plurality of switches in the second bridge arm are selectively turned on or turned off. The ratio of the input voltage to the output voltage can be adjustable by changing the turn numbers of the first winding, the second winding and the third winding.

Abstract: To improve cooling capability, power conversion apparatus 1 that converts a direct current voltage into an alternating current voltage includes: first substrate 100 on which power conversion circuit 2 is mounted; second substrate 200 on which driving circuit 3 that drives power conversion circuit 2 is mounted; and shield plate 300 that is disposed between first substrate 100 and second substrate 200, and first substrate 100 is a metal substrate.

Abstract: An inverter apparatus is disclosed in this application, which includes a plurality of protection units and a plurality of inverter units. For any protection unit, when a voltage at an input terminal of the protection unit is greater than a voltage at an output terminal of the protection unit, a path between the input terminal and the output terminal of the protection unit is in a forward conducted state; when the voltage at the output terminal of the protection unit is greater than the voltage at the input terminal voltage of the protection unit, the path between the input terminal and the output terminal of the protection unit is in a reverse cut-off state; and when a control terminal of the protection unit receives a first trigger signal, the path between the input terminal and the output terminal of the protection unit is in a reverse conducted state.

Abstract: A three-phase grid-connected inverter, a control system thereof and a control method therefor. The inverter is a three-phase three-leg grid-connected inverter, and a filter capacitor is connected to a negative electrode of a DC input bus to form a filter loop, so as to filter harmonic wave in the circuit, realizing high-quality grid-connected current at small power, without increasing an inductance value, so that the parallel inverter device in the system operates stably and thus is applicable to photovoltaic microinverters. Moreover, the three-phase three-leg grid-connected inverter operates in a discontinuous conduction mode, that is, in a switching cycle, the inductive current is reduced to 0, so that the switching loss of the three-phase three-leg grid-connected inverter is reduced.

Abstract: Blood pump for percutaneous insertion into a heart's ventricle comprising an electrical motor for driving the blood pump, the electrical motor comprising at least tree motor winding units, wherein each motor winding unit is individually connectable to a power supply via two separate phase supply lines connected to the respective motor winding unit terminals. Motor controller for driving and controlling the electrical motor of the blood pump, wherein the motor controller comprises corresponding phase supply line driving units for each motor winding units of the electrical motor of the blood pump which phase supply line driving units are connected via the corresponding two-phase supply lines with the corresponding motor winding unit. Blood pump system comprising the blood pump and the motor controller.

Abstract: A power converter includes a first contact, a second contact, a third contact, a fourth contact, a first ground contact, a second ground contact, a transformer, and a first switching element to a fifth switching element. The first switching element to the fifth switching element is controllable to switch on or off to form a first configuration and a second configuration, wherein the first configuration allows a power input to the first contact to be transmitted to the third contact through a first side of the transformer, and the second configuration allows a power input to the second contact to be transmitted to the fourth contact through the first side to a second side of the transformer, thereby to distribute the DC power in the same circuit structure.

Abstract: An electric motor drive device controls driving of a motor having open windings of two or more phases having end points that are open to each other. The switching arbitrator determines switching between a single-sided and dual-sided drive mode and arbitrates output of each of the inverters at a time of switching wherein output of the motor is continuous before and after the drive mode switching. The single-sided drive mode is a mode in which one of the two inverters performs switching drive. The dual-sided drive mode in which both the two inverters perform switching drive. The switching arbitrator gradually changes and increases the power level of the drive-start-side inverter from zero when the single-sided drive mode is switched to the dual-sided drive mode, and gradually changes and decreases the power level of the drive-end-side inverter to zero when the dual-sided drive mode is switched to the single-sided drive mode.

Abstract: A device for driving a plurality of motors, including an inverter connected to a DC terminal; a multi-phase motor connected to the inverter; and a single-phase motor serially connected to the multi-phase motor, wherein a number of frequency of current input to the multi-phase motor when driving the single-phase motor and the multi-phase motor at the same speed is smaller than the number of frequency of current input to the multi-phase motor when driving the single-phase motor and the multi-phase motor at different speeds. Accordingly, a plurality of motors can be simultaneously driven at different speeds, by using a single inverter.

Abstract: A power conversion module includes an input port, an output port, a full-bridge switching circuit, a magnetic device, an energy storage capacitor set and a rectifier circuit. The magnetic device includes a first coupled winding pair and a second coupled winding pair. The first coupled winding pair includes a first winding and a second winding, which are coupled to each other. The second coupled winding pair includes a third winding and a fourth winding, which are coupled to each other. The first winding and the third winding are connected between a first bridge arm and a second bridge arm of the full-bridge switching circuit. The energy storage capacitor set is electrically connected with the input port, and electrically connected with the first winding and the third winding. The rectifier circuit is electrically connected with the second winding, the fourth winding and the output port.

Abstract: A circuit for minimizing energy provided to a ground fault includes a source, a multiple switches, an output filter, and a controller. The switches include a first side pair of switches and a second side pair of switches configured to provide an output signal based on the source. The output filter includes one or more energy storage elements coupled to the first side pair of switches or the second side pair of switches. The controller is configured to receive a ground fault signal that indicates a fault has occurred and configured to generate a switch signal for the switches for a minimum energy state of the output filter and in response to the ground fault signal.

Abstract: A bidirectional DC-DC converter with three or more ports is described along with a method of operation thereof. The converter utilizes a common transformer for all ports and allows for power transfer from any port to any or all of the remaining ports. The converter may utilize a controller which implements variable-frequency control, delay-time control, and/or phase-delay control to achieve power transfer as desired between the converter ports. In some cases, power transfer between ports can operate similar to a series-resonant converter or a dual active bridge converter.

Abstract: To improve cooling capability, power conversion apparatus 1 that converts a direct current voltage into an alternating current voltage includes: first substrate 100 on which power conversion circuit 2 is mounted; second substrate 200 on which driving circuit 3 that drives power conversion circuit 2 is mounted; and shield plate 300 that is disposed between first substrate 100 and second substrate 200, and first substrate 100 is a metal substrate.

Abstract: An object is to obtain a power conversion device that can suppress the generation of noise due to coupling and achieve the size reduction of a substrate. In a power conversion device, a main circuit wire for connecting main circuit components to form a main circuit includes a first main circuit wire and a second main circuit wire wired so as to be separated from each other on a substrate. A control wire is wired between the first main circuit wire and the second main circuit wire so as to be insulated therefrom, and the first main circuit wire and the second main circuit wire are connected to each other via the main circuit component placed so as to be separated from the control wire in the thickness direction of the substrate.

Abstract: A system for charging a battery includes three sub-modules, each receiving a respective phase of a three-phase alternating current (AC) signal. The three sub-modules cooperate to transform the respective phases of the three-phase AC signal to a direct current (DC) signal by passing the respective phases of the three-phase AC signal through a respective semiconductor device configured to discontinuously modulate the respective phase of the three-phase AC signal to convert it to a DC signal provided to the battery to charge the battery.

Abstract: A system of driving and controlling a motor is provided. A main controller adjusts frequencies of all or some of pulse waves of an initial pulse width modulation signal to output a pulse width modulation signal according to instruction information. The adjusted frequency of each of the pulse waves is equal to a first preset frequency or a second preset frequency. When a motor driver drives the motor to stably rotate, the motor driver decodes each of the pulse waves having the first preset frequency into a first message and decodes each of the pulse waves having the second preset frequency into a second message. The motor driver arranges and combines all of the first messages and the second messages that are decoded from the pulse waves to obtain the instruction information. The motor driver executes an operation instructed by the instruction information.

Abstract: A multilink power converter with reduced winding voltage is disclosed. In the disclosed embodiments, multiple converters have their primaries or their outputs connected in series while using a single transformer winding connected to the converters' outputs through voltage blocking capacitors.

Abstract: A DC-DC power converter including: input terminals for receiving an input voltage; a pulse wave generator for generating a pulse wave; a transformer having a primary winding and a secondary winding and a magnetizing inductance; a DC blocking capacitor; a rectifier; a filter capacitor; at least one resonant inductor connected in series with the transformer; a resonant capacitor connected to the rectifier; output terminals; and a control unit for controlling operation of the pulse wave generator such when the duty cycle of the pulse wave voltage varies, high efficiency is maintained.

Abstract: Disclosed herein are a power converting apparatus and a home appliance having the same. The power converting apparatus according to an embodiment of the present invention includes an inverter having a plurality of upper switching devices and a plurality of lower switching devices, a plurality of upper gate drivers to output a gate drive signal to each of gate terminals of the plurality of upper switching devices, and a plurality of upper ON resistors disposed between the plurality of upper switching devices and the plurality of upper gate drivers, wherein resistance values of the upper ON resistors are different from each other. Thus, electromagnetic interference noise generated when the inverter is turned on or off may be attenuated without changing the switching frequency.

Abstract: A driver comprising a switched mode power supply, wherein said switched mode power supply comprises an existing coil, the driver circuit further comprises: a first power transmission antenna (42) formed as a first coil which is either the existing coil of the switched mode power supply or coupled to the existing coil of the switched mode power supply, said first power transmission antenna (42) is adapted for being magnetically coupled to a second power receiving antenna (44) thereby forming a wireless power transmitter.

Abstract: Disclosed herein is a method for controlling a trip event of an inverter by taking into account the temperature of the inverter. The method includes: sensing a change in temperature of the inverter for an overload current measurement time using the temperature sensing circuit; determining an amount of heat emitted from the inverter based on the change in temperature; determining an electrical energy of the inverter consumed for the overload current measurement time; determining a compensation reference time based on the amount of heat and the electrical energy; and comparing the compensation reference time with the overload current measurement time to trip the inverter. As a result, the actual temperature of the inverter measured when the inverter is in operation is reflected, so that the trip event of the inverter can be controlled more accurately.

Abstract: Disclosed herein is a low voltage direct-current (DC)-DC converter. The low voltage DC-DC converter includes a switching portion which includes a first switching portion and a second switching portion and changes a high voltage provided from a high voltage battery to an alternating current (AC) voltage, a transformer which converts the AC voltage output from the switching portion into a low voltage, and a switching portion zero voltage switching auxiliary circuit portion which is connected between the high voltage battery and the switching portion and operates when operations of the first and second switching portions change to consume residual energy in the switching portion.

Abstract: In a stand-by state where a power receiving device is not mounted on a power transmission device, ON/OFF of a switching element that applies an AC voltage to an active electrode and a passive electrode is controlled. A controller detects a potential difference between the active electrode and the passive electrode, and determines that the power receiving device is mounted on the power transmission device when the potential difference has changed. The controller starts ON/OFF control of switching elements and starts power transmission to the power receiving device from the power transmission device. With this, a power transmission device capable of achieving reduction in power consumption in the stand-by state and a wireless power transmission system including the same can be provided.

Abstract: At least one monitor circuit monitors a temperature of at least one monitored element of switching elements of a power conversion circuit. At least one arrival determination circuit determines that a temperature of at least one non-monitored element of the switching elements has increased and reached a passing temperature. Based on the temperature of the monitored element and arrival determination signals, a temperature estimating unit obtains a temperature difference by subtracting a current temperature of the monitored and non-monitored element at the arrival determination time from an output limitation temperature set for each of the monitored and non-monitored element, and estimates a limitation subject temperature of the monitored or non-monitored element having a smallest temperature difference among the temperature differences.

Abstract: A driver comprising a switched mode power supply, wherein said switched mode power supply comprises an existing coil, the driver circuit further comprises: a first power transmission antenna (42) formed as a first coil which is either the existing coil of the switched mode power supply or coupled to the existing coil of the switched mode power supply, said first power transmission antenna (42) is adapted for being magnetically coupled to a second power receiving antenna (44) thereby forming a wireless power transmitter.

Abstract: A semiconductor device that controls a motor driving device. The semiconductor device includes: a position detection section that detects changes in a turning position of a rotor provided at a motor and outputs detection signals corresponding to the changing turning position; a first switching section that, in accordance with the detection signals, outputs ground switching signals, which switch which end portion of a coil is connected to a ground side, to a first switching circuit; and a second switching section that, in accordance with the detection signals, outputs connection switching signals, which switch which end portion of the coil is connected to a driving power supply side, to a third switching circuit that controls the switching of connections between the end portions of the coil and the driving power supply side by a second switching circuit.

Abstract: A driver circuit (e.g., an LED driver circuit) provides power to a load (e.g. an LED light source) from a DC power rail. A self-oscillating LLC series resonant inverter is configured to connect to the DC power rail, receive DC power from the DC power rail, and provide an AC output signal. A current limiting circuit is connected to the self-oscillating LLC series resonant inverter. The current limiting circuit receives the AC output signal from the self-oscillating LLC series resonant inverter and provides an AC current signal as a function of the DC current provided to the load by the driver circuit. The rectifier circuit receives the AC current signal from the current limiting circuit and provides a DC current to the load.

Abstract: A driver circuit (e.g., an LED driver circuit) provides power to a load (e.g. an LED light source) from a DC power rail. A self-oscillating LLC series resonant inverter is configured to connect to the DC power rail, receive DC power from the DC power rail, and provide an AC output signal. A current limiting capacitor is connected to the self-oscillating LLC series resonant inverter. The current limiting capacitor receives the AC output signal from the self-oscillating LLC series resonant inverter and provides an AC current signal. The rectifier circuit receives the AC current signal from the current limiting capacitor and provides a DC current to the load.

Abstract: Provided is an apparatus and method for controlling medium voltage inverter, whereby a frequency outputted by the medium voltage inverter is fixed, in a case an instantaneous power interrupt occurs while the medium voltage inverter drives a motor, and a voltage level of an AC power generated by the medium voltage inverter is reduced and outputted in response to a predetermined deceleration slope to control the medium voltage inverter.

Abstract: There is provided an even-level inverter, including: a voltage-dividing circuit dividing input DC power into an even number of voltage levels; a plurality of switching devices connected to individual nodes of the voltage-dividing circuit having the even number of voltage levels; and a bidirectional switching device connected to the individual nodes of the voltage-dividing circuit through at least one of the plurality of switching devices and including at least two transistors. According to the present invention, the bidirectional switching device is implemented without a diode to thereby reduce conduction loss caused due to an anti-parallel diode included in the related art bidirectional switching device, and a neutral point of the voltage-dividing circuit is electrically separated from the switching devices to thereby control reactive power.

Abstract: The present application relates to a cascaded H-Bridge medium voltage drive, a power cell, and a bypass module thereof, wherein the bypass module is configured for bypassing a major circuit module of the power cell, while the major circuit module comprises a fuse, a rectifier, a bus capacitor and an H-Bridge inverter, two points led from the H-Bridge inverter being configured as a first output end and a second output end; a bypass circuit comprises a first bridge arm and a second bridge arm; a point led from the first bridge arm is configured as a first input end of the bypass circuit, a point led from the second bridge arm is configured as a second input end of the bypass circuit, and the first input end is electrically connected with the first output end, the second input end is electrically connected with the second output end.

Abstract: When a failure detection part detects a failure in an inverter circuit in a first power supply system, a drive control part stops the inverter circuit from driving a motor. An on/off control part turns off a first power supply relay of a power supply on/off part. Under a state that the inverter circuit stops a motor driving operation, a first coil set of the motor generates an induced voltage by rotation caused by an external force. The induced voltage is regenerated to a battery from the inverter circuit through a second power supply relay and a parasitic diode of the first power supply relay. Thus, circuit elements in the power supply system, which is failing, are protected from breaking down.

Abstract: A power converter includes an inverter unit that includes a plurality of semiconductor switching elements constituting upper and lower arms and converts DC power into AC power; a gate driving unit that outputs, to the inverter unit, a gate signal used to drive gates of the plurality of semiconductor switching elements; a driving control unit that supplies the gate driving unit with a switching control signal used for the gate driving unit to output the gate signal; a first abnormality detection unit that performs over voltage detection of the DC power and over current detection of the AC power and temperature detection of the upper and lower arms; and a second abnormality detection unit that detects abnormality of the plurality of semiconductor switching elements of the upper arm and lower arms, wherein the driving control unit includes a first protection circuit and a second protection circuit.

Abstract: The present invention provides a safe circuit that can prevent an arm short, when a half-bridge circuit is configured by using a normally-on switching element, and the half-bridge circuit is used as a driver circuit or an inverter circuit. In a driver circuit configured by a half-bridge circuit in which one of input and output terminals of a first switching element 14 is connected to a first power-supply voltage V1 on a high-voltage side, and the first switching element 14 and a second switching element 15 are connected in series, a normally-off third switching element 16 is inserted between the second switching element 15 and a second power-supply voltage V2 on a low voltage side. The third switching element 16 is turned off, when an operating voltage VH or VL supplied from control-circuit power supplies 13a and 13b is insufficient for the operation of a control circuit 11.

Abstract: An inverter device includes: an inverter circuit configured to perform ON/OFF operations with a preset duty cycle to convert a DC power into an AC power and output the AC power to an AC motor; and a controller configured to change a duty cycle of the ON/OFF operations.

Abstract: A circuit for protecting a controllable power switch is provided. The controllable power switch has a first power switch terminal connected to a first terminal, a second power switch terminal connected to a second terminal, and a power switch control terminal. Further, the circuit includes a diode with a first diode terminal and a second diode terminal, and a controllable control switch having a first control switch terminal connected to the first diode terminal, a second control switch terminal, and a control switch control terminal. A signal applied to the power switch control terminal is based on a signal at the second control switch terminal. Further a method for protecting a controllable power switch is described.

Abstract: A photovoltaic (PV) system is disclosed that provides dynamic regulation of the output of a PV array such that the inverter can safely operate without entering a voltage protection mode. The PV system includes a PV array that generates a direct current (DC) output from received solar radiation and a DC link coupled to the PV array to receive the DC output therefrom. The PV system also includes a DC-to-AC power inverter electrically coupled to the DC link to receive the DC output therefrom and invert the DC output to an AC output and a damping circuit electrically coupled to the DC link and positioned between the PV array and the DC-to-AC power inverter. The damping circuit includes a damping resistor and a damping switch.

Abstract: A power converter system includes a converter, a DC link, an inverter, a damping circuit, and a control system. The converter includes an input to couple to a power generation unit and an output to provide a direct current (DC) DC power output. The DC link includes a capacitor coupled to the converter output. A voltage across the capacitor defines a DC link voltage. The inverter includes an input coupled to the DC link. The damping circuit is coupled between the converter and the inverter in parallel with the DC link capacitor. The damping circuit includes a normally closed switching device, and a resistor coupled in series with the normally closed switching device. The control system is coupled to the damping circuit and configured to control the normally closed switching device as a function of at least one operating parameter of the power converter system.

Abstract: An electrical circuit for a power converter is described. The circuit has been provided with several semiconductor switches and capacitors used for operating the power converter. A brake resistance for lowering energy is provided and is connected to the semiconductor switches provided without the need for an additional switch. The operation of the power converter and the current flowing through the brake resistance can be controlled by means of the existing semiconductor switches.

Abstract: A system and method of discharging a bus capacitor of a bidirectional matrix converter of a vehicle are presented here. The method begins by electrically shorting the AC interface of the converter after an AC energy source is disconnected from the AC interface. The method continues by arranging a plurality of switching elements of a second energy conversion module into a discharge configuration to establish an electrical current path from a first terminal of an isolation module, through an inductive element, and to a second terminal of the isolation module. The method also modulates a plurality of switching elements of a first energy conversion module, while maintaining the discharge configuration of the second energy conversion module, to at least partially discharge a DC bus capacitor.

Abstract: When determining a fault current portion IF in a differential current idiff(t) measured by an inverter, an AC voltage uAC(t) applied to an AC output of the inverter is measured and a periodic reference function y(t) of alternating sign is generated as a function of the measured AC voltage uAC(t) in order to determine an AC fault current portion IFAC in the differential current idiff(t). The differential current idiff(t) is multiplied by the periodic reference function y(t), and the product of the differential current idiff(t) and the reference function (y(t)) is averaged over an integral number of periods of the reference function y(t). The reference function y(t), at least for one operating state of the inverter, is generated with a predefined phase offset with respect to the measured AC voltage uAC(t) and/or with a frequency which is an integer multiple of the frequency of the measured AC voltage uAC(t).

Abstract: In an electric power conversion system having a discharge control device capable of discharging a voltage charged in a capacitor to a voltage of not more than a predetermined voltage, a linear regulator decreases a voltage of the capacitor and outputs the decreased voltage to a drive unit at a bottom arm in a U phase. A flyback converter for discharging use inputs an output of the linear regulator, and outputs electric power to a drive unit at an upper arm in the U phase. When detecting that own vehicle collides with an obstacle, the discharge control device starts to execute discharge control of the capacitor by turning off a photo coupler and turning on the linear regulator.

Abstract: A method and apparatus for controlling and monitoring an H-bridge via a single communication path. The apparatus comprises a first control and monitor module coupled to a first switch within the H-bridge; and a first pulse transformer coupled to a first control signal to the first control and monitor module, wherein the first control and monitor module (i) generates, based on the first control signal, a first driver signal for operating a first switch of the H-bridge during DC/AC power conversion, (ii) monitors at least a portion of the H-bridge for at least one fault, and (iii) communicates, upon detecting the at least one fault, a first fault indication to a main controller of the H-bridge via the first pulse transformer.

Abstract: The present invention relates to a method for compensating a current of a DC/DC converter that detects an average value of a pulsatory current that is output as a chopping wave form from an inductor that is used in a DC/DC converter to compensate an offset value in real time. A method for compensating a current of a DC/DC converter can include analyzing a PWM signal for a switching DC-DC converter, if the PWM signal is on, comparing a delay time with a rise half cycle size between a detected current and a real current that is output by an inductor, calculating a current variation amount and determining an offset compensation value for compensating a current variation amount according to the comparison result of the rise half cycle size and the delay time, and applying the offset compensation value to compensate the detected current of the inductor.

Abstract: The present subject matter is directed to systems and methods for improving reliability of dual bridge doubly fed induction generators (DFIGs) by reducing the number of required components in the converters associated with such DFIGs. A converter is constructed using a pair of current conducting bridges wherein one of the current conducting bridges is controlled and the second is not controlled. The uncontrolled bridge may correspond to a pair of diodes while the controlled bridge may correspond to a pair of transistors, in particular, a pair of IGBT transistors.

Abstract: A switch driving circuit electrically opens and closes a switch circuit including two N-channel type semiconductor switching elements series connected in a reverse direction, thereby electrically opening and closing a path between a DC power supply and an inverter circuit. The switch driving circuit has a reference potential point in common with the inverter circuit and supplies an opening/closing control signal to the switch circuit. The switch driving circuit includes a half bridge circuit including two semiconductor switching elements series connected between a driving power supply and the reference potential point. Two protection diodes are connected in parallel to the semiconductor switching elements respectively. At least one current blocking diode is configured to block current from flowing from the reference potential point through the diode to the switching circuit side when the DC power supply is connected to the inverter circuit in reverse polarity.

Abstract: A current source inverter includes an inverter having arm units and AC terminals, the numbers of the arm units and AC terminals being adapted to an AC load connected to the AC terminals. An upper arm is connected between a positive DC terminal and the corresponding AC terminal and has an upper arm switch Q7 (Q2, Q3) and an upper arm diode. A lower arm is connected between a negative DC terminal 5 and the corresponding AC terminal and has a lower arm switch Q8 (Q5, Q6) and a lower arm diode. The apparatus also includes a smoothing reactor and a DC power source that are connected in series between the positive DC terminal and the negative DC terminal, and includes drivers to control ON/OFF of the upper and lower aim switches to output AC power. The switches Q7 and Q8 are each a normally-ON switch.

Abstract: A power supply topology is used in which a transistor is provided on the side of an output node of a rectifying circuit. An inductor is provided on the side of a reference node, a resistor is inserted between the transistor and the inductor, and one end of the resistor is coupled to a ground power supply voltage of a PFC circuit. The PFC circuit includes a square circuit which squares a result of multiplication of an input voltage detection signal and feedback information (output voltage of an error amplifier circuit). The PFC circuit drives on the transistor when a detection voltage developed at the resistor reaches zero, and drives off the transistor when the detection signal reaches an output signal of the square circuit.

Abstract: A voltage inverter capable of operating in the event of a short-circuit or open-circuit fault. The voltage inverter includes: a load having three phases, each phase having a first terminal and a second terminal; first and second cells each including three branches connected together in parallel, each branch including two switches connected in series and a mid-point positioned between the two switches, each first terminal of each of the phases being connected to one of the mid-points of the first cell and each second terminal of each of the phases being connected to one of the mid-points of the second cell; and a DC voltage source, the first and second cells each being connected to the DC voltage source via two electrical isolators.