Abstract: A power conversion device includes a power conversion controller that generates gate signals for controlling operation of a three-phase three-level inverter and of three single-phase inverters, based on sinusoidal phase voltage commands. In the power conversion controller, the sinusoidal phase voltage commands are divided into three-phase instantaneous voltage commands to be indicated to the three-phase three-level inverter, and mean voltage commands to be indicated to the respective three single-phase inverters. When the sum of the three-phase instantaneous voltage commands is a positive value, a common voltage component is superimposed on each of the three mean voltage commands to make the sum of the three mean voltage commands a non-positive value, and when the sum of the three-phase instantaneous voltage commands is a negative value, the common voltage component is superimposed on each of the three mean voltage commands, making the sum of the three mean voltage commands non-negative.

Abstract: A high-voltage generator may be provided. The high-voltage generator may include a rectifying unit, a grid-controlled unit, and a shielding device. The rectifying unit may be configured to rectify an electric current generated in the high-voltage generator. The grid-controlled unit may be configured to generate a high voltage and electrically connected to the rectifying unit. The grid-controlled unit may have a conductive surface that opposes the rectifying unit. The shielding device may be located between the rectifying unit and the conductive surface of the grid-controlled unit. The shielding device may be spaced apart from the rectifying unit and the conductive surface of the grid-controlled unit. The shielding device may be electrically connected to the rectifying unit.

Abstract: A self-oscillating converter includes a power transistor coupled to a primary winding for controlling current flow in the primary winding, and a turn-on circuit configured to turn on the power transistor for maintaining oscillation in the self-oscillating converter. The self-oscillating converter also includes a turn-off circuit configured to turn off the power transistor to maintain an on-time of the power transistor at a pre-set value for power factor correction, and modulate the on-time of the power transistor to regulate the output current in the load device.

Abstract: Disclosed are a control method and control system for a modular multilevel converter and a power transmission system. The control method includes calculating an actual capacitor voltage of the sub-module; calculating a reference capacitor voltage of the sub-module; dividing the plurality of sub-modules into a plurality of modules, reference capacitor voltages of the sub-modules in the same module are the same, and reference capacitor voltages of the sub-modules from different modules are different; sorting in the module to obtain a first voltage sequence; sorting among different modules to obtain a second voltage sequence; and determining the sub-modules to be switched on or switched off according to charging and discharging states of the sub-module, the first voltage sequence and the second voltage sequence, until an actual level of the bridge arm is consistent with a desired level, wherein the desired level changes using a first preset value as a step.

Abstract: In the present invention, in an electromagnetic device that uses a coil current, such as a motor, an initial value of a desired coil current waveform is inputted, a magnetic field analysis is performed for the electromagnetic device, a power supply voltage waveform which is derived from a magnetic vector potential acquired from the analysis is calculated, and a circuit coupled magnetic field analysis is performed by using a fundamental waveform component of the calculated power supply voltage waveform, thereby providing a power supply voltage waveform calculation method and a circuit coupled magnetic field analysis method for obtaining a steady solution more quickly than in the conventional technique.

Abstract: A method of short-circuiting a faulty submodule for a voltage-source power converter is disclosed. The submodule is based on a full-bridge, asymmetric full-bridge or half-bridge circuit design having power semiconductor switches with anti-parallel freewheeling diodes and optionally non-controllable semiconductor valves. The method 36 includes identifying a faulty semiconductor device and determining a failure mode selected from a short-circuit failure mode and an open circuit failure mode. The method further includes selecting a minimum number of power semiconductor switches suitable to provide a bypass path through the submodule depending on the identified faulty semiconductor device and the determined failure mode and driving the selected power semiconductor switches by a modified driving voltage compared to normal operation to cause them to break down in order to provide a durable, stable, low impedance short-circuit path between the AC voltage terminals of the submodule.

Abstract: A neutral arrangement is provided for a converter station of a direct current power transmission system that includes a first converter. The neutral arrangement includes surge arrestors and a group of neutral buses. Each surge arrestor is connected between a neutral bus and ground. The neutral arrangement includes a high voltage insulation zoom area having a first group of surge arrestors and a low voltage insulation zoom area having a second group of surge arrestors. The surge arrestors in the first group have a first arrestor reference voltage and the surge arrestors in the second group have a second arrestor reference voltage that is lower than the first arrestor reference voltage.

Abstract: This application discloses a phase alignment circuit and a method of a receive end, and a receive end. The receive end is located on an electric vehicle. The phase alignment circuit includes a phase measurement circuit and a controller. The controller is configured to: use, as an actual phase shift angle, a result obtained by subtracting a phase difference from a preset phase shift angle, and control a phase of a bridge arm voltage of a rectifier to lag behind the phase of the input current fundamental component by the actual phase shift angle. The controller outputs a drive signal for a controllable switching transistor of the rectifier by using the actual phase shift angle. Because a lagging phase caused due to filtering is compensated for, precision of synchronization between the bridge arm voltage and the input current can be increased.

Abstract: When a winding density represents the number of turns of a wire per unit length in a longitudinal direction of a core portion, a plurality of inductor regions having mutually different winding densities of the wire are arrayed in the longitudinal direction of the core portion, and a low-density inductor region with the winding density being relatively low is located between first and second high-density inductor regions with the winding densities being relatively high.

Abstract: An isolation transformer and an energy transfer device having an isolation transformer are disclosed. In an embodiments an isolation transformer includes an input winding, an output winding, a third winding, a capacitive element and a resistive element, wherein the capacitive element, the resistive element and the third winding are connected in series, and wherein the input winding, the output winding and the third winding are magnetically coupled.

Abstract: The invention relates to a modular multilevel converter (10) including a control module (12) for regulating the internal energy stored in the capacitors of the submodules of an arm of the converter, the control module being suitable for limiting the internal energy to below an upper limit and/or to above a lower limit, by using parameters measured on the DC power supply network (110) and on the AC power supply network (120) together with setpoints for the operating power of the converter.

Abstract: The present invention provides a method of MMC for HVDC. According to the present invention, there is provided a redundancy control method of an MMC for HVDC, wherein the MMC includes multiple converter arms each has multiple submodules in operation and redundancy modules for spares, the method including: checking whether a breakdown of a submodule in operation of a first converter arm among the multiple converter arms occurs in a case where the all redundancy modules of the first converter arm are applied in operation; and lowering an output voltage of each submodule of other converter arms in such a manner that a DC link voltage of each of the other converter arms is controlled to be equal to a DC link voltage of the first converter arm when the breakdown of the submodule of the first converter arm occurs.

Abstract: An object of the present invention is to reduce the size of a power conversion apparatus and to improve the reliability. The power conversion apparatus includes a power semiconductor module, a driver circuit board mounted with a driver circuit, an AC-side relay conductor for transferring the alternating current, and an AC connector. The power semiconductor module includes an AC-side terminal connected to the AC-side relay conductor, and a control-side terminal connected to the driver circuit board. The AC connector is provided on the opposite side of the power semiconductor module through the driver circuit board. The driver circuit board includes a transformer for transforming voltage from low to high and supplying the transformed voltage to the driver circuit, and a line for connecting the transformer and the driver circuit. Further, the driver circuit board forms a through hold provided on the side opposite to the transformer with the driver circuit interposed therebetween.

Abstract: A control system and a method for an on-board battery charger (OBC) of a vehicle generate a DC link voltage instruction through a proportional integral control that regards, as an instruction, a resonance switching frequency determined by a resonance capacitance and a resonance inductance of the LLC converter and allow the switching frequency of an LLC converter to operate at the resonance frequency, thus enhancing efficiency of the OBC.

Abstract: A high voltage direct current power transmission series valve group control device, is used for regulating a series circuit having two or more valve groups provided with controllable power semiconductors respectively. Each valve group is provided with a current regulation unit and a voltage regulation unit. The current regulation unit controls a direct current current flowing through a valve group corresponding thereto, and the voltage regulation unit controls a voltage across two ends of a valve group corresponding thereto. One valve group is selected from the series valve group as a master control valve group, while the others are taken as slave control valve groups. The master control valve group selects a trigger angle output by the current regulation unit to control same, and the slave control valve group selects a trigger angle obtained after the trigger angle transmitted from the master control valve group and an output value of the voltage regulation unit pass through a subtractor to control same.

Abstract: A power conversion device including: an energy storage unit which receives and stores voltage of a self-power-feeding device; and a bypass unit drive device which, when voltage of the self-power-feeding device becomes smaller than a predetermined lower limit value, causes a bypass unit to perform short-circuiting operation by power stored in the energy storage unit. Thus, by appropriately setting the above voltage lower limit value as a threshold value for the short-circuiting operation, it becomes possible to swiftly and reliably perform short-circuiting protection operation even if a cell converter has failed, thus it is possible to always safely continue the operation of the power conversion device.

Abstract: A power generation system includes at least one generator that generates a medium voltage direct current that has a positive DC voltage output and a negative DC voltage output. The system also provides a medium voltage DC (MVDC) cable system with a positive pole cable and a negative pole cable, wherein the positive pole cable is connected to the positive DC voltage output and the negative pole cable is connected to the negative DC voltage output. A substation is connected to the MVDC cable system and includes at least one DC/DC step-up converter to step-up the medium voltage direct current to a high voltage direct current.

Abstract: A high voltage transformer for cascade coupling wherein the high voltage transformer comprises a primary winding, a high voltage winding and a transformer core, and wherein the primary and high voltage windings encircles concentrically at least a part of the transformer core, and wherein the high voltage transformer is provided with a secondary winding, as the high voltage winding comprises one or more single layers connected in parallel.

Abstract: A multilevel AC/DC power converter device includes a high-frequency power converter including a first AC port and a low-frequency power converter including a second AC port and a DC port. A power converting method includes: serially connecting the first AC port of the high-frequency power converter and the second AC port of the low-frequency power converter; operating frequency of the low-frequency power converter synchronized with frequency of an AC power source and operating the high-frequency power converter with high-frequency PWM to generate a multilevel AC voltage; and controlling the multilevel AC voltage to obtain a current of an input AC port being sinusoidal and in a same phase with a voltage of the AC power source. Accordingly, the input power factor approaches unity and the low-frequency power converter supplies a DC voltage to a load via a DC output port.

Abstract: A power electronic building block includes a housing; a power module mounted within the housing; a controller mounted within the housing and coupled to the power module; a capacitor assembly coupled to the power module and mounted within the housing; an AC bus bar mounted within the housing; and a DC bus bar coupling the capacitor assembly to the power module and mounted within the housing.

Abstract: There is a control circuit comprising first and second DC terminals for connection to a DC network, the first and second DC terminals having a plurality of modules and at least one energy conversion element connected in series therebetween to define a current transmission path, the plurality of modules defining a chain-link converter, each module including at least one energy storage device, the or each energy storage device being selectively removable from the current transmission path to cause a current waveform to flow from the DC network through the current transmission path and the or each energy conversion element and thereby remove energy from the DC network, the or each energy storage device being selectively removable from the current transmission path to modulate the current waveform to maintain a zero net change in energy level of the chain-link converter.

Abstract: An interface device between an electrical network and energy consumer systems, including an input converter with a first winding connected on one side with a reverse blocking module and on the other with a first semiconductor chopper device, second and third windings having an end connected to output converters via first and second reverse blocking modules, and another end connected to the output converters, via a switching cell, a fourth winding having an end to be connected to the network, via a second semiconductor chopper device; and a control module for the semiconductor chopper devices. The interface device also includes a buffer capacitor having a first end connected to the output converters, and another end, to which a reference voltage is applied, isolated from the network; and a power reserve having an end to be connected to the network and another end connected to the fourth winding.

Abstract: A method and apparatus for controlling the output voltage of a boost converter including a number n of bridge devices connected in series, each bridge device including plural switches and a capacitor. The method and apparatus provide control of the switches according to a selected periodical matrix pattern including a number N of time intervals, N being a positive integer greater than 2, and in that in each time interval, the voltage between the input and the output of each ith bridge device with i from one to n, is equal to one of a null value, a number ki times a positive value, and minus the number ki times the positive value, the positive value being the result of the division of the output voltage of the boost converter including the n bridge devices by the number of time intervals N of the periodical matrix pattern.

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 high-efficiency high step-up ratio direct current converter with an interleaved soft-switching mechanism is provided. The direct current converter includes a voltage-multiplier circuit and an active clamping circuit. The voltage-multiplier circuit includes two isolating transformers, two main switches disposed on a primary side of the two isolating transformers, four diodes disposed on a secondary side of the two isolating transformers and four capacitors disposed on the secondary side of two isolating transformers, configured to boost a voltage of a direct-current power to a desired voltage value. The active clamping circuit, electrically connected to the voltage-multiplier circuit, includes two active clamp switches and a clamp capacitor to lower a voltage surge of the two main switches so that the two main switches and the two active clamp switches can be soft switched on.

Abstract: A cascaded electric power converter and a method of operating a cascaded electric power converter are disclosed. The cascaded converter includes: a converter cell including a cell capacitor and at least one phase leg having at least two electric valves, the at least one phase leg being connected in parallel to the cell capacitor; and a control system for controlling the switching of the electric valves of the at least one phase leg. The control system is configured to, upon detection of a need to by-pass the converter cell, control the switching of the electric valves in a manner so that the cell capacitor is short circuited via a phase leg, so as to obtain a current surge through the phase leg, thereby creating a permanent current path through the converter cell.

Abstract: A power conversion apparatus including a three-phase transformer interconnected to a three-phase power system, the three-phase transformer including a primary winding group that receives three-phase electric power of the three-phase electric power system, a first secondary winding group and a second secondary winding group that receive electric power transferred from the primary winding group, and a first converter group and a second converter group connected to the first and second secondary winding groups, respectively, the power conversion apparatus further including a DC output terminal group connected to at least one of other ends of the first to third converter arms provided in the first converter group, and connected to at least one of other ends of the fourth to sixth converter arms provided in the second converter group.

Abstract: Disclosed is a circuit arrangement for determining a temporal change of an output voltage of a half-bridge circuit during a dead time. In one embodiment, the circuit arrangement includes a first input for applying the output voltage. A capacitive network includes a first and a second circuit node capacitively coupled to the input, and having a terminal for a reference potential. A recharging circuit during the switched-on phase of one of a first and second switching elements, adjusts electrical potentials of the first and second nodes, the electrical potentials each being different from the reference potential. A comparator arrangement, during the dead time, determines a time difference between such times at which the electrical potentials at the first and second node each assume a given potential value, the time difference being a measure for the change with time of the output voltage.

Abstract: A boosting AC-to-DC converter An AC-to-DC converter may include a main rectifier, a first auxiliary rectifier, a second auxiliary rectifiers and a transformer assembly. The transformer assembly may include a set of primary windings arranged in a first multiphase configuration and connected to the main rectifier, a first set of secondary windings arranged in a second multiphase relationship and connected to the first auxiliary rectifier and a second set of secondary windings arranged in a third multiphase configuration and connected to the second auxiliary rectifier. The second multiphase configuration of the first set of secondary windings and the third multiphase configuration of the second set of secondary windings may be in phase shifting relationships relative to the first multiphase configuration of the set of primary windings.

Abstract: An embodiment of a power supply includes an input node, a converter stage, and an outlet. The input node is operable to receive an input AC signal having peak portions and non-peak portions. The converter stage is operable to generate a DC power signal from the input AC signal and to cause a first current to be drawn from the input node during at least the non-peak portions of the input AC signal. And the outlet is operable to carry the DC power signal. For example, such a power supply may be installed in a facility such as a residence, office building, or manufacturing plant, or the facility's existing power supply may be retrofitted, to provide one or more power outlets that each carry a respective power-factor-corrected (PFC) DC voltage. Because the outlet voltages are PFC voltages, the amount of wasted power dissipated in the facility power lines/wiring and in the main power lines from the power company may be significantly reduced, without requiring each piece of equipment (e.g.

Abstract: The present invention concerns a method for controlling an output voltage of a boost converter composed of n bridge devices connected in series, each bridge device being composed of plural switches and a capacitor, the switches being controlled by periodical patterns decomposed in time intervals.

Abstract: In a general aspect, a charge transfer includes a transformer including a plurality of primary windings and a plurality of galvanically isolated secondary windings, a first plurality of resonant converters having input terminals connected in series to an input power terminal and having output terminals connected to different primary windings of the plurality of primary windings, a second plurality of resonant converters having input terminals connected to different secondary windings of the plurality of secondary windings and having output terminals connected to a galvanically isolated power terminal, and a control system for controlling a transfer of electric charge between the input power terminal and the galvanically isolated output power terminal including controlling a first plurality of switches of the first plurality of resonant converters and a second plurality of switches of the second plurality of resonant converters in a zero current soft switching mode.

Abstract: Disclosed is a power conversion device, wherein among the optical fiber cables used in control/communication, at least the majority of high-voltage optical fiber cables with a dielectric strength against the output voltages of a plurality of cells can be eliminated and thus a low-voltage optical fiber cable with a dielectric strength against the output voltage of one cell can be used. Furthermore, here, the length required for the optical fiber cable can be reduced. A controller of the power conversion device comprising a plurality of cascade-connected cells comprises a central controller, and a cell controller with the same potential as each cell, the cell controller being installed in the vicinity of each cell, wherein the central controller and each cell controller are daisy-chained using an optical fiber cable.

Abstract: A power supply device includes a transformer, a rectification smoothing circuit having positive and negative output ends that rectifies and smoothes an induced voltage at a secondary winding of the transformer so as to generate a direct current voltage between positive and negative output terminals, a serial connection terminal to which another power supply device is connectable and is connected to the positive output end, the negative output terminal is connected to the negative output end, the reverse flow prevention rectifying device is connected between the positive output end and the positive output terminal, its forward direction faces toward the positive output terminal, and the bypass rectifying device is connected between the positive output end and the negative output end, its forward direction faces toward the positive output end. Therefore, a plurality of power supply devices are easily connected in series without providing external diodes for each power supply device.

Abstract: A method is described for controlling a plurality of parallel-connected power converters 20a, 20b, each of which operates in accordance with a pulse width modulation (PWM) strategy defined by an independent voltage carrier signal and an independently controllable modulating sinusoidal voltage signal which are used to generate a PWM command signal for each PWM strategy. The voltage carrier signals of the PWM strategies have the same switching period and desynchronisation of the PWM command signals causes an unwanted circulating current to flow between the power converters 20a, 20b. The method thus comprises providing the independently controllable modulating sinusoidal voltage signal of the PWM strategy of at least one of the plurality of power converters 20a, 20b with a dc voltage offset to modify the PWM command signal of the at least one power converter and thereby increase the synchronisation of the PWM command signals so that the magnitude of any unwanted circulating current is reduced.

Abstract: A modular direct-current power conversion system is applied to receive a DC input voltage and output a DC output voltage. The modular direct-current power conversion system includes a main board and a plurality of DC power conversion modules. The main board includes a primary surface, a voltage input terminal, a voltage output terminal, a plurality of insertion regions, and a plurality of pin holders. When the DC power conversion module is inserted on the main board, the DC input voltage is inputted via the voltage input terminal to the DC power conversion module. The DC power conversion module converts the DC input voltage into a DC output voltage, and the DC output voltage is outputted via the voltage output terminal.

Abstract: In the present invention, provided is a power conversion apparatus in which at least one energy storage element and at least one switching element are included, a plurality of series circuits of a transformer winding and an arm in which one or a plurality of at least two-terminal unit converters which depend on ON/OFF of the switching element and supply a zero voltage or a voltage depending on a voltage of the energy storage element are connected in series are connected in parallel, and a multi-phase power source or a multi-phase load is connected to another winding of the transformer, and the parallel-connection point is set as a DC terminal, and which includes means for controlling a current flowing through each of the arms to have a phase and amplitude different from each other.

Abstract: An input power circuit for a battery-powered device, such as a toy or consumer electronic device, includes a polarity correction circuit portion. The device includes a first input terminal and a second input terminal, a first output terminal and a second output terminal, and a diode with a forward voltage drop of about 0.5 volts or less. In embodiments, the polarity correction circuit portion is configured to provide a positive voltage polarity at the first output terminal and a negative voltage polarity at the second output terminal for any polarity of power at the first input terminal and the second input terminal. The polarity correction circuit portion can include a diode bridge, and the diode may include a Schottky diode or a germanium diode.

Abstract: According to one embodiment, an AC power system includes a first AC/DC converter to be coupled to a direct current (DC) load and a multi-phase AC power supply. The system further includes a second AC/DC converter coupled in parallel with the first AC/DC converter via an interphase transformer to the DC load and the multi-phase AC power supply. The system further includes a controller coupled to the first and second AC/DC converters, where the controller is configured to generate a gate trigger signal for firing each of the rectifiers for the first and second AC/DC converters. During a first power cycle, a rectifier of the first AC/DC converter is fired at a firing angle advanced to a firing angle of a corresponding rectifier of the second DC/DC converter. During a second power cycle, the rectifier of the first AC/DC converter is fired at a firing angle lagging to a firing angle of the corresponding rectifier of the second AC/DC converter.

Abstract: A power conversion device includes: a plurality of cascade-connection type single-phase power converters; and a central control unit that controls the plurality of the single-phase power converters, wherein each of the plurality of single-phase power converters has a single-phase power converter control unit, and the central control unit and the plurality of the single-phase power converter control units are connected via a communication means having a daisy-chain configuration, wherein the single-phase power converter control unit transmits and receives a control signal via the communication means having the daisy-chain configuration, as well as a specific pattern signal, other than a control signal frame, which can be distinguished from the control signal frame, and determines a communication error due to not receiving the specific pattern signal at the single-phase power converter control unit, or an inconsistency between the received signal and the specific pattern signal.

Abstract: A model for a silicon controlled rectifier includes three diode models connected in series, with the middle diode model being reverse biased. Each diode model corresponds to and can be configured to simulate DC operation of a junction in the silicon controlled rectifier. The model can be used to evaluate behavior of a circuit that includes the silicon controlled rectifier. For example, the circuit can include an electrostatic discharge protection circuit that includes the silicon controlled rectifier.

Abstract: A power conversion device includes at least two legs connected in parallel each of which includes at least two unit converters connected in series, wherein at least one of the legs is formed using at least two kinds of unit converters including a first type unit converter capable of outputting a unipolar voltage and a second type unit converter capable of outputting a bipolar voltage.

Abstract: A power converter enhances conversion efficiency from DC power to AC power. A first chopper circuit chops DC voltage from a photovoltaic panel at a system frequency producing a first square-wave whose voltage level changes positively. A second chopper circuit chops the first square-wave at a frequency double the system frequency producing a second square-wave whose voltage level changes negatively and adds the first square-wave and the second square-wave to produce a third square-wave that changes positively and negatively in a sine-wave manner. A third chopper circuit charges and discharges by chopping the third square-wave at a third frequency fixed by timing according to a difference between the third square-wave and a sine-wave voltage. PWM control is performed on the charge and discharge outputs such that the difference is corrected, producing a sine-wave voltage that continuously changes positively and negatively. A spike noise of an output voltage is suppressed.

Abstract: The invention is directed to a voltage rectifier (23) comprising at least two diode arrays (33, 34, 35, 36) each comprising plural diodes (33a, 33b, 33p, 34a, 34b, 35a, 35b, 35p, 36a, 36b, 36c, 36d, 36p) connected in series. The diode arrays are arranged in an enclosure (47). The diode arrays are arranged in a special arrangement for providing an even distribution of a field strength. According to an embodiment and with respect to the figures, the vertical distance between an enclosure (47) and the diode arrays (33, 34, 35, 36) increases when horizontally distancing from the direct current terminals. Further, the invention provides a voltage generator (21) and a voltage rectifier (23) having such a voltage rectifier.

Abstract: Systems and methods presented herein generally provide for the controlled voltage of bipolar electrical energy through the selected operation of power stages. In one embodiment, a system that provides electrical energy includes a power supply and at least two power stages coupled to the power supply. The power stages are operable to selectively output electrical energy. By selecting the number of power stages which are turned on at a given time the total voltage of the electrical energy is controlled at that time. The system may further include one or more controllers coupled to the power stages to control selection of the power stages and thereby vary the output voltage.

Abstract: A high voltage AC/DC or DC/AC power conversion system including a voltage source converter with at least two series-connected converter valve bridges, at least two reactors, where each of the reactors is connected to one of the AC phase terminals of the at least two bridges and at least one transformer connected to an AC supply voltage. In order to block a DC voltage from the at least one transformer, one of at least two capacitors is connected in series with each of the at least two reactors and is connected between the corresponding reactor and the at least one transformer.

Abstract: A converter cell module and a voltage source converter system. The converter cell module includes at least two switching elements, means for energy storage and an autotransformer. The autotransformer is arranged to bypass the converter cell module in the case of failure occurring in the converter cell module.

Abstract: An HVDC transmission system including a rectifier station and an inverter station each having a series connection of at least two converters. A by-pass DC breaker is connected in parallel with each converter. A control device is adapted to deblock a blocked converter by starting to control the converter at high delay angle and gradually decreasing the delay angle until substantially all DC current flows through the converter and to then control the by-pass breaker to open at substantially zero current, and to stop the operation of a converter by controlling the converter at gradually increasing delay angle until the voltage across the converter is substantially zero and to then control the converter to be blocked by firing a by-pass pair thereof and to then control the by-pass breaker to close for taking over all the DC current when the voltage between a neutral bus and a pole of a transmission line between the stations is to be increased and reduced, respectively.

Abstract: The invention relates to a power converter comprising, in particular, a rectifier comprising at least one switching leg provided with two transistors (T1-T6) connected in series. The transistors (T1-T6) are of the normally ON field-effect type, for example JFETs, and are each controlled by a gate control device (CT1-CT6). Each gate control device comprises, in particular: an output (OUT1) connected to the gate (G) of the controlled transistor, a voltage rectifier element connected between the output of the control device and an input (in1, in3) of the converter, a capacitor (C11) connected between the source (S) of the transistor and a point situated between the output of the control device and the voltage rectifier element.

Abstract: A method of on/off modulation of a very high frequency switching cell-based power converter includes receiving an input voltage signal to be applied to a plurality of series stacked very high frequency power converter cells for producing an output voltage and/or current, and controlling a portion of the plurality of series stacked high frequency power converter cells through on/off modulation of at least one of the plurality of series stacked high frequency power converter cells to control the output current and/or the output voltage.