Abstract: A zero voltage switching circuit includes a zero voltage switching unit which forms a full-bridge circuit at the primary side of a converter and comprises a plurality of switches for zero voltage switching; an adjustable inductor which performs zero voltage switching in resonance with a parasitic capacitor of the zero voltage switching unit, and is adjusted according to control of a control unit; and the control unit which controls inductance of the adjustable inductor according to an input voltage of the zero voltage switching unit or an electric current flowing in the adjustable inductor.

Abstract: There are provided a plurality of drive circuits (103 U, 103 L) for driving respective plural switching devices constituting upper arms and lower arms, a power supply circuit for supplying a power supply to the plurality of drive circuits, and a discharge circuit for discharging a capacitor. The power supply circuit includes a first transformer (201U) for the upper arms, and a second transformer (201L) for the lower arms, which include a primary winding connected in parallel to a DC power supply. The first transformer and the second transformer include a secondary winding for supplying a power supply to the drive circuits and for supplying a power supply to a low-voltage circuit (110). Each of the first transformer and the second transformer includes a feedback winding for outputting the voltage output to the drive circuits, to a power supply control IC. The discharge circuit (120) is driven by a power supply supplied from the feedback winding.

Abstract: A smoothing capacitor is forcibly discharged, in a state where a battery is disconnected from a high-voltage circuit, first discharge control is initiated to consume electric charges of the smoothing capacitor by an in-vehicle component via a DC/DC converter. Thereafter, when a voltage of the smoothing capacitor is reduced and reaches a specified threshold, second discharge control is executed to forcibly discharge the electric charges in an active discharge circuit. In the case where continuous forced discharge occurs, delay control to delay execution timing of the second discharge control is further executed.

Abstract: Methods and apparatus which use a microinverter comprising integrated neutral forming function for off-grid facilities are provided herein. For example, a microinverter configured for use with an AC storage system comprises switching circuitry connected at an AC output of the microinverter, a three-line connector connected at the AC output and comprising a neutral line connected between two lines configured to connect to at least one of a single phase grid system or a split phase grid system, wherein the neutral line is connected to the microinverter at a point that maintains a mid-way voltage between the two lines voltage.

Abstract: A power inverter, such as a synchronous buck power inverter, that is configured with a high frequency switching control having a (PWM) controller and sensing circuit. Controller provides a low frequency oscillating wave to effect switching control on a synchronous-buck circuit portion that includes a plurality of switches to invert every half cycle of the frequency provided by controller. The inverting process thus creates a positive and negative transition of the oscillating wave signal. A low frequency switching stage includes a further plurality of switches configured to operate as zero voltage switching (ZVS) and zero current switching (ZCS) drives Charge on an output capacitor is discharged to zero on every zero crossing of low frequency switching stage and advantageously discharges energy every half cycle. During this discharge of energy, the zero crossing distortion in the low frequency sine wave is greatly reduced.

Abstract: A soft switching sub-circuit forming part of or for use with a circuit. The soft switching sub-circuit comprises a bridge switching circuit. The soft switching sub-circuit is configured and operable to provide a varying current output that tracks output current from the bridge switching circuit to create a substantially zero current through at least one switch component of the bridge switching circuit to enable soft switching.

Abstract: A voltage source converter includes first and second DC terminals which have at least one converter limb extending therebetween. Each limb portion includes a chain-link converter that extends between an associated AC terminal and a corresponding one of the first or the second DC terminal. Each chain-link converter also includes a chain-link converter controller which is programmed to control a series of connected chain-link modules. The voltage source converter additionally includes a voltage source converter controller which is arranged in operative communication with each chain-link converter controller to coordinate operation of the chain-link converters. Each chain-link converter controller is further programmed to reconstruct from a received modulation index demand the chain-link converter voltage reference, which the chain-link converter it is controlling is required to produce, by multiplying the received modulation index demand by a total voltage sum established at a first time instant.

Abstract: A power conversion device is provided, and includes a major circuit part, and a control device; the major circuit part includes a power conversion part converting, into AC power, power that is input, and a filter circuit causing the AC power output from the power conversion part to approach a sine wave; the control device controls power conversion by the major circuit part by controlling an operation of the power conversion part; the control device includes an overcurrent suppression controller; the overcurrent suppression controller calculates instantaneous value voltage output command values of the phases of the AC power output from the power conversion part to suppress an overcurrent at the output end of the major circuit part. Accordingly, a power conversion device and a control device of the power conversion device are provided in which the generation of an overcurrent can be suppressed even when a voltage-controlled operation is performed.

Abstract: A power control apparatus, comprising: a first wiring and a second wiring connected to a power source; a first capacitor connected to the first wiring and the second wiring; an electrical component including a plurality of switches connected in parallel with the first capacitor through the first wiring and the second wiring; and a second capacitor which is connected to one of the first wiring and the second wiring and is connected to a reference potential portion having a constant potential, wherein an impedance of a first conducting path between another side connection point, which is connected to the first capacitor, of the other one of the first wiring and the second wiring and the power supply not through the first capacitor, is higher than an impedance of a second conducting path between the another side connection point and the second capacitor through the first capacitor.

Abstract: A switch circuit, a mixer, and an electronic device, where the switch circuit includes a first metal oxide semiconductor (MOS) transistor, a second MOS transistor, a third MOS transistor, and a fourth MOS transistor, both a gate of the first MOS transistor and a gate of the fourth MOS transistor are connected to a first port, and both a gate of the second MOS transistor and a gate of the third MOS transistor are connected to a second port; and a lead between the gate of the first MOS transistor and the first port, a lead between the gate of the second MOS transistor and the second port, a lead between the gate of the third MOS transistor and the second port, and a lead between the gate of the fourth MOS transistor and the first port all have an equal length. In this way, linearity is relatively high.

Abstract: A semiconductor device includes: a semiconductor element that converts DC electric power into AC electric power; a DC terminal that transmits DC electric power; an AC terminal that transmits AC electric power; a sealing member that seals the semiconductor element, at least a part of the DC terminal, and at least a part of the AC terminal; and at least one floating terminal that is arranged between the DC terminal and the AC terminal.

Abstract: The present disclosure discloses a sub-module hybrid MMC with low full-bridge ratio and a DC fault processing method thereof. The hybrid MMC prevents the energy at the AC side from entering a DC system by artificially creating three-phase interphase short circuit at the AC side of a converter in the DC fault processing process, which greatly reduces the ratio of full-bridge sub-modules required for DC fault processing. Moreover, the hybrid MMC has the same DC fault processing speed as the sub-module hybrid MMC with high full-bridge. The duration of the artificially created three-phase interphase short circuit fault in the fault processing process does not exceed 30 ms, which will not have a great impact on the AC system.

Abstract: A three-level converter includes a first power switch, which has a first end connected to a first DC input end and a first end of a third power switch. A second end of a second power switch is connected to a second DC input end and a second end of a fourth power switch. A connection point between a second end of the first power switch and a first end of the second power switch is a first AC output end. A connection point between a second end of the third power switch and a first end of the fourth power switch is a second AC output end. Fifth and sixth power switches are connected in series between the first AC output end and a neutral end. A seventh power switch is connected between the second AC output end and a connection point between the fifth and sixth power switches.

Abstract: A motor drive system for an electrified vehicle includes a DC source, such as a battery, and an inverter, which includes one or more phase drivers, each configured to switch current from the DC source to generate AC power upon one or more output terminals using a hybrid of two or more different solid-state switches, each having a corresponding voltage rating. A nine-switch inverter includes three phase drivers, each including high, low, and middle solid-state switches, with Si-MOSFET high and low switches having a first voltage rating of half of the rated voltage of the system, and with Gallium Nitride (GaN) transistors rated to block a full rated voltage of the system used for the middle switches. A delay driver synchronizes timing between two different solid-state switches by energizing control terminals at different rates. The inverter can be operated using near-state pulse-width modulation (NSPWM) to reduce switching losses.

Abstract: A distributed power system including multiple DC power sources and multiple power modules. The power modules include inputs coupled respectively to the DC power sources and outputs coupled in series to form a serial string. An inverter is coupled to the serial string. The inverter converts power input from the serial string to output power. A signaling mechanism between the inverter and the power module is adapted for controlling operation of the power modules.

Abstract: A direct current (DC) power secondary distribution system is provided. The system comprises at least one first conversion unit and a one or more second conversion units. The first conversion unit receives alternating current (AC) electrical voltage from a distribution transformer of an AC power distribution system and converts the AC electrical voltage to DC electrical voltage output. The one or more second conversion units are connected downstream of the first conversion unit, and each second conversion unit converts the DC electrical voltage output from the first conversion unit to a respective AC electrical voltage output for a respective one or more loads. The one or more loads may be associated with a household.

Abstract: The disclosure is directed to a power module that includes at least one power substrate, a housing arranged on the at least one power substrate, and a first terminal electrically connected to the at least one power substrate. The first terminal includes a contact surface located above the housing at a first elevation. The power module includes a second terminal including a contact surface located above the housing at a second elevation different from the first elevation, a third terminal electrically connected to the at least one power substrate, and a plurality of power devices electrically connected to the at least one power substrate.

Abstract: Provided is a hybrid modular multilevel converter (HMMC) based on a neutral point clamped (NPC) topology and having an ABC N-phase structure. The HMMC includes N pairs of identical upper and lower arms, each upper and lower arm being composed of X submodules and Y sets of switches. The switches within each set are cascaded and connected in series, each of the submodules is formed of full-bridge silicon (Si) insulated-gate bipolar transistor (IGBT) converters, and at least one of the set of switches is formed of IGBTs of opposite polarities.

Abstract: Provided is a hybrid modular multilevel converter (HMMC) based on a neutral point pilot (NPP) topology and having an ABC N-phase structure. The HMMC includes N pairs of identical upper and lower arms, each upper and lower arm being composed of X submodules and Y sets of switches. The switches within each set are cascaded and connected in series, each of the submodules is formed of full-bridge silicon (Si) insulated-gate bipolar transistor (IGBT) converters, and at least one of the set of switches is formed of IGBTs of opposite polarities.

Abstract: A virtual and parallel power extraction method by using time division, comprising an alternating current load (1), a load end time-division power extraction control device (2), a switch end time-division power extraction control device (3), and a switch end power supply load (4). The alternating current load (1) is connected in parallel with the load end time-division power extraction control device (2); the switch end time-division power extraction control device (3) is connected in parallel with the switch end power supply load (4); a combination body formed by connecting the alternating current load (1) with the load end time-division power extraction control device (2) in parallel and the combination body formed by connecting the switch end time-division power extraction control device (3) with the switch end power supply load (4) in parallel are together connected in series in an alternating current circuit.

Abstract: A method for switching off power semiconductor switches in a bridge circuit having first through sixth power semiconductor switches. The method includes a switch-off process for establishing a final switch configuration in which all power semiconductor switches in the bridge circuit are in a switched-off state. Over the course of the switch-off process, a switch configuration is established in which the fifth power semiconductor switch and the sixth power semiconductor switch are concurrently in a switched-on state, while the first power semiconductor switch and the fourth power semiconductor switch are in a switched-off state. Also disclosed is a bridge circuit having a control circuit configured to carry out such a method. In addition, an inverter that includes at least one bridge circuit of this type is also provided.

Abstract: A control substrate capable of effectively reducing noise input to a plurality of MOSFETs is provided. The control substrate includes at least three parallel snubber circuits (132, 134, and 135). Each of the parallel snubber circuits (132, 133, and 134) is connected in parallel with each of U-phase MOSFETs (126a and 126b), V-phase MOSFETs (127a and 127b), and W-phase MOSFETs (128a and 128b).

Abstract: A coupled inductor includes first and second magnetic rails, a plurality of connecting magnetic elements, and a plurality of windings. The first and second magnetic rails are separated from each other in a first direction, and the first magnetic rail has a first cross-sectional area A1 as seen when viewed in the first direction. Each connecting magnetic element is disposed between the first and second magnetic rails in the first direction. The plurality of connecting magnetic elements collectively have a second cross-sectional area A2 as seen when viewed in the first direction, and a ratio of A2/(A1?A2) is at least 1.5. A respective winding is wound at least partially around each connecting magnetic element.

Abstract: Semiconductor device A1 includes: first terminal 201A and second terminal 201B; first switching element 1A including first gate electrode 12A, first source electrode 13A and first drain electrode 14A; and second switching element 1B including second gate electrode 12B, second source electrode 13B and second drain electrode 14B. First switching element 1A and second switching element 1B are connected in series to each other between first terminal 201A and second terminal 201B. Semiconductor device A1 includes first capacitor 3A connected in parallel to first switching element 1A and second switching element 1B between first terminal 201A and second terminal 201B. First switching element 1A and second switching element 1B are aligned in y direction. First capacitor 3A overlaps with at least one of first switching element 1A and second switching element 1B as viewed in z direction. These arrangements serve to suppress surge voltage.

Abstract: An inverter device includes a converter circuit and a filter. The converter circuit converts a DC input voltage into an AC intermediate voltage based on six control signals, and includes first and second converters. Each of the first and second converters includes three switches, two diodes and a coupled inductor circuit. The switches of the first converter operate respectively based on three of the control signals. The switches of the second converter operate respectively based on the other three of the control signals. The filter filters the AC intermediate voltage to generate an AC output voltage.

Abstract: A power converter includes an inverter circuit connected between the positive and negative terminals of a DC power supply, three single-phase bridge circuits each connected in series between an AC terminal of one of different phases of the inverter circuit and a motor, and a power conversion controller that generates gate signals to control operations of the inverter circuit and the three single-phase bridge circuits based on phase voltage commands. When a semiconductor switching element of the single-phase bridge circuits fails, the power conversion controller sets the output voltage of the single-phase bridge circuit of a phase to which the faulty semiconductor switching element belongs to zero to continue operation.

Abstract: The present disclosure concerns a method and a circuit for controlling first and second switches electrically in series, wherein one or a plurality of crossings of a voltage threshold by a voltage across the first switch cause a conductive state of the second switch.

Abstract: A power conversion device converts a direct-current power on the DC side of the power conversion device to an alternating-current power by an inverter circuit having a plurality of semiconductor switching elements, and outputs the AC power from the AC side of the power conversion device. A current detector detects a reactor current output from the inverter circuit. As overcurrent detector detects overcurrent in a control mode in which the reactor current is caused to follow a reactor current command value, control circuit starts an overcurrent mode in which a time period where the reactor current monotonically decreases is provided. In the overcurrent mode, whether to switch the overcurrent mode to the normal control mode is determined based on the reactor current or in accordance with a timing corresponding to a zero-cross point of a voltage or current on the AC side.

Abstract: The present application provides a power component of a three-level converter, a three-level converter and a wind turbine. The power component of the three-level converter includes: a first NPC bridge arm unit including a plurality of first NPC bridge arms connected in parallel; a second NPC bridge arm unit including a plurality of second NPC bridge arms connected in parallel; and a third NPC bridge arm unit including a plurality of third NPC bridge arms connected in parallel. The number of the second NPC bridge arms is the same as the number of the first NPC bridge arms, and the number of the third NPC bridge arms is determined based on the ratio of the loss of the first NPC bridge arm to the loss of the third NPC bridge arm.

Abstract: A method for feeding electrical power into an electrical supply network using an inverter-controlled infeed unit is provided. The infeed unit has an inverter arrangement with a plurality of inverters to generate an output power and feed same into the network. Each inverter has an associated isolating switch to galvanically isolate the respective inverter from the network. Each inverter has a circuit composed of switches to generate an output current using pulsed actuation. Each inverter generates a variable partial power, and the output power is a sum of all partial powers. Depending on the output power, one or more of the inverters are operated as active inverters that respectively generates a partial power. The other inverters are operated as passive inverters that do not generate a partial power. One or more of the passive inverters are operated as blocked inverters and remain galvanically connected to the network.

Abstract: A bridge circuit includes a first leg and a second leg arranged in parallel between the first node and the third node. A clamp circuit includes a third leg including a first bidirectional switch disposed between a fourth node that is a midpoint of the first leg and a fifth node that is a midpoint of the second leg. A first reactor is connected with the fourth node and a sixth node, and a second reactor is connected with a fifth node and a seventh node. A fourth leg includes a second bidirectional switch disposed between the second node and the fourth node or the fifth node.

Abstract: Systems, apparatuses, and methods are described for discharging an input voltage by utilizing discharge circuitry configured to produce a relatively constant discharge voltage value/output voltage, a relatively constant discharge current value/output current, or a relatively constant discharge power value/output power. The discharge circuitry may include at least one power device, such as a DC to DC converter.

Abstract: A source-network coordination type direct-current (DC) circuit breaker based on pre-charged capacitors for an MMC based DC grid is provided. The MMC based DC grid is provided with four converter stations, each having two converters, which are in loop connection through a double-loop DC overhead line. Two ends of each DC line connecting the converters are separately equipped with DC circuit breakers for isolating a fault of the DC line. An MMC active voltage adjusting control strategy is matched with pre-charged capacitor voltage in the self-adaptive mode to provide a beneficial breaking condition for a quick mechanical switch branch, so that the fault line is effectively cut off.

Abstract: A system and method for combining power from DC power sources. Each power source is coupled to a converter. Each converter converts input power to output power by monitoring and maintaining the input power at a maximum power point. Substantially all input power is converted to the output power, and the controlling is performed by allowing output voltage of the converter to vary. The converters are coupled in series. An inverter is connected in parallel with the series connection of the converters and inverts a DC input to the inverter from the converters into an AC output. The inverter maintains the voltage at the inverter input at a desirable voltage by varying the amount of the series current drawn from the converters. The series current and the output power of the converters, determine the output voltage at each converter.

Abstract: A system and method for combining power from DC power sources. Each power source is coupled to a converter. Each converter converts input power to output power by monitoring and maintaining the input power at a maximum power point. Substantially all input power is converted to the output power, and the controlling is performed by allowing output voltage of the converter to vary. The converters are coupled in series. An inverter is connected in parallel with the series connection of the converters and inverts a DC input to the inverter from the converters into an AC output. The inverter maintains the voltage at the inverter input at a desirable voltage by varying the amount of the series current drawn from the converters. The series current and the output power of the converters, determine the output voltage at each converter.

Abstract: A method relating to control of a system including a single-phase three-level quasi-Z type source inverter connected to an LC filter which is in turn connected to a load, the inverter including first and second bridge arms, each including a plurality of switches, the method including the steps of (a) for each of a plurality of consecutive sampling periods (i) determining the duration of a shoot-through period for the next sampling period during which the inverter is in shoot-through mode; (ii) choosing a configuration of the switches for the next sampling period (iii) at the end of the sampling period setting the switches in the chosen configuration for the next sampling period; and (b) at a time during the next sampling period and for the duration of the shoot-through period setting the switches such that the inverter is in shoot-through mode.

Abstract: A method for operating a multi-level bridge power converter includes providing a plurality of switching devices of the power converter in one of a neutral point clamped topology or an active neutral point clamped topology. The method also includes providing a plurality of deadtimes for the switching devices. Further, the method includes selecting one of the deadtimes for each of the switching devices such that at least two of the switching devices operate according to different deadtimes. Moreover, the method includes operating the switching devices at the selected deadtimes to allow a first group of the switching devices to switch slower than a second group of the switching devices such that the first group of the switching devices satisfy safe operating requirements while the second group of the switching devices switch faster than the first group.

Abstract: An uninterruptible power supply (UPS) is provided that includes a split direct current (DC) link having a first capacitor coupled between a positive DC link terminal and a first node, and a second capacitor coupled between the first node and a negative DC link terminal. The UPS also includes a rectifier coupled to an input of the split DC link and a controller coupled to the rectifier. The rectifier includes first, second, and third legs, wherein each leg is configured to convert a first alternating current (AC) voltage received from an AC source into a DC voltage to be provided to the split DC link, and a fourth leg configured to balance DC link voltages of the first and second capacitors. The controller is configured to maintain functionality of the rectifier during at least one of a partial utility power outage, a full utility outage, and a failure of at least one of the first, second, third, and fourth legs.

Abstract: A circuit comprising a first power node for connection to a positive voltage of a DC link, a second power node for connection to a negative voltage of the DC link and a mid-point power node for connection to a mid-point voltage of the DC-link, the circuit further comprising a three-level neutral point clamped converter module and a brake resistor connection.

Abstract: Various embodiments according to the present invention relate to a power conversion device and method, the device comprising: a converter; a capacitor unit including a plurality of capacitors for storing input voltage input thereto; a switch unit connected to the capacitor unit and including a plurality of switches for selectively connecting at least one capacitor among the plurality of capacitors to the converter; and a controller connected to the capacitor unit and the switch unit, wherein the controller determines at least one capacitor satisfying a specified condition, among the plurality of capacitors, sets at least one switch among the plurality of switches to be turned on, the at least one switch corresponding to the at least one capacitor, and sets at least another switch among the plurality of switches except for the at least one switch, to be turned off, so that the at least one capacitor and the converter are electrically connected and configured to allow at least partial voltage of the input volta

Abstract: An inductive driver circuit with improved speed of clamping down a powered solenoid element, which solenoid exhibits inductive properties, for purposes of rapid shut down of the solenoid.

Abstract: An electronic device includes a first voltage conversion unit that divides an input voltage and outputs the divided voltage, a detection unit that detects the input voltage, and a control unit that controls the voltage division ratio of the first voltage conversion unit such that the output voltage of the first voltage conversion unit decreases as the input voltage increases.

Abstract: A method manages a fault on a DC voltage side of a converter assembly including a modular multistage converter with switching modules having semiconductor switches and an energy store. Some switching modules are a first type and others are a second type. During operation, a positive switching module voltage, negative switching module voltage or zero voltage are generated at terminals of switching modules of the first type, and a positive switching module voltage or zero voltage are generated at terminals of switching modules of the second type. Upon detecting a DC voltage side fault, switching modules of the first type are actuated such that the polarity of their energy store voltages corresponds to the polarity of a fault current, and energy stores of switching modules of the first type are charged to a voltage exceeding their rated voltage. A converter assembly carrying out the method is also provided.

Abstract: The power supply device includes a first winding, a second winding, a third winding, a fourth winding, a first AC-DC conversion unit, a second AC-DC conversion unit, a first power supply terminal and a second power supply terminal. The first and second windings are disposed on a secondary side of a multi-pulse transformer, and coupled to an input of the first AC-DC conversion unit. The first power supply terminal is coupled to an output of the first AC-DC conversion unit. The third and fourth windings are disposed on the secondary side of the multi-pulse transformer, and coupled to an input of the second AC-DC conversion unit. The second power supply terminal is coupled to an output of the second AC-DC conversion unit. Phases of output voltages of the first winding, the third winding, the second winding and the fourth winding are successively shifted left or successively shifted right for 15°.

Abstract: Systems and methods presented herein provide for multivariable model predictive control of a multistep plant. In one embodiment, a model predictive controller (MPC) includes a model of the multistep plant. The MPC is operable to linearize at least two steps of the multistep plant into cycle steps based on the model, to process an output signal from the multistep plant, and to independently control the cycle steps based on the output signal to optimize an output of the multistep plant.

Abstract: A control system for a multiphase electric motor comprises processing means arranged to determine a pattern of PWM voltage waveforms to be applied to respective phases of the motor, the processing means assigning different PWM patterns for use with different motor positions. In use for a given rotational position of the motor the processing means is normally adapted to apply PWM waveforms according to the assigned PWM pattern unless a different PWM pattern is currently in use at that time, except that in the event that the demanded voltage waveforms cannot be achieved with the current PWM pattern the processing means is adapted to force the PWM pattern to change. Upon the rotor moving into a different position associated with a different assigned pattern the processing means forces the PWM pattern to change to the assigned PWM pattern.

Abstract: A power supply device includes a storage battery, a capacitor unit connected to the storage battery, a power converter including three phases connected to the storage battery in parallel, a control device configured to control a switching on and off of switching elements included in the three phases respectively, a first connection terminal connected to a P terminal of a DC charger and located between first and second switching elements in any one of the three phases, and a second connection terminal connected to an N terminal of the DC charger and located between third and fourth switching elements in another one of the three phases.

Abstract: Disclosed is a rectifying device provided with a standby power reduction function. When a voltage of unsmoothed DC power, which is output from a rectifying unit that rectifies AC power, is lowered to be equal to or smaller than a discharge reference voltage at a time around a zero-crossing point of the AC power, the present invention can instantaneously discharge a capacitor, which has been charged with the unsmoothed DC power, to be synthesized with the unsmoothed DC power, and thus supply stable DC power to a load without using an electrolytic capacitor. In particular, the present invention can adjust a resistance value of a surge prevention switch connected in series with the capacitor to control a current amount flowing through the capacitor, and thus can prevent a surge voltage from being generated when charging and discharging the capacitor.

Abstract: A power conversion device may include a first inverter to which one end of each phase winding of a motor is coupled, a second inverter to which the other end of each phase winding is coupled, and a switch circuit having at least one of a first switch element that switches between connection and disconnection of the first inverter to and from a ground, a first protection circuit being coupled in parallel to the first switch element, and a second switch element that switches between connection and disconnection of the second inverter to and from the ground, a second protection circuit being coupled in parallel to the second switch element.

Abstract: A method for controlling shutdown wave blocking of a multilevel inverter circuit and an application apparatus for applying the method are provided. After a shutdown command is issued, the multilevel inverter circuit is controlled to switch between a free state and a specific turn-on state. The free state is a state in which all switch tubes in the multilevel inverter circuit are turned off. The specific turn-on state is a state in which voltage stress withstood by a switch tube, on which clamping protection is not performed, in the multilevel inverter circuit is zero by controlling a specific combination of switch tubes in the multilevel inverter circuit to be turned on.