| Entries |
| Document | Title | Date |
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| 20080205093 | Apparatus for Electrical Power Transmission - A device for the transmission of electrical energy includes at least one current converter. Each current converter has phase elements with respective arrangements of circuit elements that comprise at least two switchable power semiconductors each and at least two free-wheeling diodes, each connected in parallel thereto, and energy storing means. The transfer properties in or between power distribution networks are improved with the novel device. The device is provided with means for controlling the current converter in such a manner that the zero crossing, the amplitude and/or the instantaneous values of an alternating current of a transfer network that can be connected to the device and/or the direct current of a direct current line that connects at least one current converter to a direct current source, and/or the direct voltage and the direct current of at least three interconnected current converters can be controlled. | 08-28-2008 |
| 20080212342 | Control Method for Direct-Current Transmission - In a method for controlling a rectifier and an inverter, which are connected together by a direct current circuit, a measuring direct current voltage and respectively, a measuring direct current are measured at at least one measuring point of the direct current circuit and are transmitted to a direct current control for controlling the rectifier and/or an inverter control for controlling the inverter. The direct current control controls the rectifier in such a manner that a total of a difference direct current voltage and a differential direct current is minimal and the inverter control of the inverter is controlled in such a manner that the difference between the differential direct current of the differential direct current voltage is minimal. The method is reliable and is economical. Accordingly, the desired flow of the direct current control and the desired flow of the inverter control are identical. | 09-04-2008 |
| 20090168468 | Converter Station - A converter station for connecting an AC system to a bipolar HVDC transmission line. A DC neutral arrangement is provided with first DC breakers enabling breaking of a first current path from a neutral bus of one pole of the transmission line to a neutral bus of another pole at bipolar operation of the station for isolation of a faulty section and changing to monopolar operation/metallic return thereof. The DC neutral arrangement has in the first current path at least two first DC breakers connected in series and adapted to act as a backup for each other would the other thereof fail to break the first current path upon a control to isolate a faulty section by changing from bipolar to monopolar operation. | 07-02-2009 |
| 20090196077 | ENERGY MANAGEMENT SYSTEM AND CONTROL METHOD USING THE SAME - The present disclosure relates to an energy management system (EMS) and a method using the same, wherein the EMS comprises, a communication module receiving a channel information of a high voltage direct current (HVDC) system via a network; a circuit realization unit obtaining a connection information among constituent elements symbolizing the constituent elements among each node in electrical symbols by sequentially following pre-set nodes of the HVDC system, and forming the HVDC system by connecting the symbolized constituent elements using electrical lines by using the channel information of HVDC system received by the communication module; a system analyzing unit analyzing an operation mode of the HVDC system through the connection information among the constituent elements of the HVDC system obtained by the circuit realization unit; and a controller managing and controlling the HVDC system by giving an energy management command in response to the operation mode analyzed by the system analyzing unit. | 08-06-2009 |
| 20090201702 | Converter Station - A converter station for connecting an AC system to a bipolar HVDC transmission line. A DC neutral arrangement includes first DC breakers enabling breaking of a first current path from the neutral bus of one pole to the neutral bus of the other pole at bipolar operation of the station for changing to monopolar operation thereof for isolation of a faulty section of the system while establishing a current path to electrode line connecting members for diverting the current from the one pole thereto. A separate connecting member is provided for each of the electrode lines. A connector is configured to connect each neutral bus to an optional of the two electrode line connecting members. | 08-13-2009 |
| 20090219737 | TRANSMISSION SYSTEM AND A METHOD FOR CONTROL THEREOF - 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. | 09-03-2009 |
| 20090279328 | HVDC SYSTEM AND METHOD TO CONTROL A VOLTAGE SOURCE CONVERTER IN A HVDC SYSTEM - A method to control a voltage source converter in a HVDC system includes controlling a frequency and a voltage amplitude of an AC voltage generated by the voltage source converter independently of the conditions in an AC network connected to the voltage source converter. The method is performed by a control unit of an HVDC system. The method may form a basis of a method to black start an AC network. The AC network includes transmission lines and is connected to at least two AC power stations. One of the at least two AC power stations is connected via a HVDC system to the AC network. | 11-12-2009 |
| 20090296428 | CONTROL AND SUPPLY SYSTEM - In accordance with at least some embodiments, a maritime well system includes a sea-surface control unit. The maritime well system also includes a sea-bed control unit coupled to the sea-surface control unit by a sub-sea cable configured to carry a direct current (DC) voltage output from the sea-surface control unit at least 30 kilometers to the sea-bed control unit. The maritime well system also includes a sub-sea tree coupled to the sea-bed control unit via a connecting line configured to carry a converted voltage output from the sea-bed control unit to the sub-sea tree. In accordance with at least some embodiments, the cross-sectional area of the sub-sea cable is designed to carry a predetermined amount of power to the sea-bed control unit as DC power and is at least 10 times smaller than a cross-sectional area needed for carrying the predetermined amount of power to the sea-bed control unit as alternating current (AC) power. | 12-03-2009 |
| 20090303758 | CONVERTER - A converter for converting alternating voltage into direct voltage and vice versa in a converter station of a high voltage transmission system including a series connection of a plurality of converter valves. The converter has connections to transformers on both of two opposite sides of the converter valves. | 12-10-2009 |
| 20090303759 | DC filter and voltage source converter station comprising such filter - The resistors of a filter block in a voltage source converter station are connected with a floating neutral point. | 12-10-2009 |
| 20090316446 | TRANSMISSION SYSTEM - A HVDC transmission system including at one end of a bipolar HVDC transmission line a converter station for connecting the transmission line to an AC system. The station has two converters and a DC neutral arrangement in common to the converters. The DC neutral arrangement has a separate electrode line connecting member connecting to electrode lines. The electrode lines are dimensioned to be able to at monopolar operation of the converter station transmit substantially full current to an electrode station through the remaining one or ones of the electrode lines at disconnection of an arbitrary of the electrode lines. | 12-24-2009 |
| 20100046255 | HVDC SYSTEM - An HVDC network including a first station including a first converter, a second station including a second converter, each converter including non-extinguishable semiconducting elements. A first transmission conductor and a second transmission conductor. The first station includes a first switching arrangement. | 02-25-2010 |
| 20100085783 | METHOD AND SYSTEM TO INFLUENCE THE POWER GENERATION OF AN ADJUSTABLE SPEED GENERATOR - A method and a system to influence the power generation of at least one adjustable speed generator. The system includes a first voltage source converter connected to a local AC bus. The local AC bus is provided with power by the at least one adjustable speed generator. A second voltage source converter connected to an AC grid. A DC link is connected between the first and the second voltage source converter. At least one control unit controls the first and the second voltage source converters. The at least one control unit performs the method to control the AC voltage in the local AC bus via the first voltage source converter and to modify a reference value for the AC voltage magnitude of the local AC bus in dependence on the AC voltage magnitude of the AC grid. | 04-08-2010 |
| 20100091527 | TAPPING POWER FROM A HVDC TRANSMISSION SYSTEM - An apparatus for tapping electric energy from an HVDC power transmission system includes at least one voltage source converter. The apparatus includes an intermediate ac network containing the voltage source converter, and a switching arrangement for disconnecting the intermediate ac network in dependence on the transmission direction of the HVDC power transmission system. | 04-15-2010 |
| 20100091528 | METHOD AND ARRANGEMENT TO REVERSE THE POWER FLOW OF A DIRECT CURRENT POWER TRANSMISSION SYSTEM - A direct current power transmission system includes a first and a second converter station that are coupled to each other via a direct current link. Each converter station includes a first or second line commutated converter, respectively. Before power reversal the first converter is operated as a rectifier and the direct current is controlled in the first station, while the second converter is operated as an inverter and in the second station the extinction angle of the second converter or the direct voltage is controlled. After power reversal, the first converter is operated as an inverter and the second converter as a rectifier. During power reversal a change is carried out in the first station from control of the direct current to control of the extinction angle of the first converter or to control of the direct voltage, which is performed in synchronization with a change in the second station from control of the extinction angle of the second converter or from control of the direct voltage to control of the direct current. | 04-15-2010 |
| 20100232190 | CONVERSION OF AC LINES TO HVDC LINES - An electric power transmission system includes at each end of a high voltage direct current transmission line including three conductors, a converter station for conversion of an alternating voltage into a direct voltage for transmitting direct current between the stations in all three conductors. Each station has a voltage source converter and an extra phase leg connected between the two pole conductors of the direct voltage side of the converter. A third of the conductors is connected to a midpoint between current valves of the extra phase leg. An arrangement is adapted to control the current valves of the extra phase leg to switch for connecting the third conductor either to the first pole conductor or the second pole conductor for utilizing the third conductor for conducting current between the stations. | 09-16-2010 |
| 20110080758 | PLANT FOR TRANSMITTING ELECTRIC POWER - A plant for transmitting electric power comprises a direct voltage network for High Voltage Direct Current and at least one alternating voltage network connected thereto through a station. The station comprises at least one Voltage Source Converter adapted to convert direct voltage into alternating voltage and conversely. In the direct voltage network at least one parallel connection of at least one semiconductor device of turn-off type and a resistor is connected in series with a direct voltage line of the direct voltage network. | 04-07-2011 |
| 20110096575 | PLANT FOR TRANSMITTING ELECTRIC POWER - A plant for transmitting electric power through HVDC comprises two converter stations interconnected by a bipolar direct voltage network and each connected to an alternating voltage network. Each converter station has a Voltage Source Converter with switching cells each including at least one energy storing capacitor. The Voltage Source Converters are configured to utilize a direct voltage having a higher magnitude for a first of the poles than for a second thereof with respect to ground. | 04-28-2011 |
| 20110141773 | HVDC CONNECTION OF WIND TURBINE - A method and apparatus for connection of a wind driven turbine generator to an HVDC transmission line is provided that does not require transformation of the wind generated AC voltage to a nominal AC distribution grid frequency. An AC output from the turbine generator is increased in level and converted to HVDC for direct application to a HVDC transmission line. The wind turbine generated AC may be first increased in frequency via a matrix converter and then rectified or may be first rectified and increased in level by a high-voltage DC-DC converter circuit and then applied directly to the HVDC transmission line. | 06-16-2011 |
| 20110170320 | TRANSMITTING ELECTRIC POWER INTO A BORE HOLE - A system for transmitting electric power into a bore hole, the system having an electric transmission line extending through the bore hole between an electric power source and a receiving station, wherein the receiving station includes frequency increasing means for increasing the frequency of the electric current supplied through the electric transmission line, voltage converter means for changing the voltage of the electric current supplied to it via the frequency increasing means, connecting means for supplying the frequency-increased electric current to the voltage converter means, and means for connecting an electric load to the receiving station. | 07-14-2011 |
| 20110310641 | METHOD OF UPGRADING A PLANT FOR TRANSMITTING ELECTRIC POWER AND SUCH A PLANT - A plant for transmitting electric power through HVDC includes two converter stations interconnected by a monopolar direct voltage network and each having an alternating voltage side for feeding electric power from one of said alternating voltage sides to the other. Each station has a line commutated converter. The plant is upgraded by making the direct voltage network bipolar, providing each station with a Voltage Source Converter and providing two switches for both line commutated converters or both Voltage Source Converters and a device configured to control said four switches. | 12-22-2011 |
| 20120026760 | DC VOLTAGE COMPENSATION IN A MULTI-TERMINAL HVDC POWER TRANSMISSION NETWORK - In a multi-terminal HVDC power transmission network comprising at least three HVDC converter stations interconnected by at least two transmission lines, where at least one of the transmission lines is a long line, an active voltage source device is series connected to one of the transmission lines, which maintains the DC voltage of the transmission lines of the network to be within a predefined voltage range by injecting an additional DC voltage in series with the one transmission line. | 02-02-2012 |
| 20120033461 | CONTROLLING A HIGH-VOLTAGE DIRECT-CURRENT (HVDC) LINK - The present disclosure is directed to a High Voltage Direct Current (HVDC) link with Voltage Source Converters VSC and interconnecting two power systems. A model-predictive control with a receding horizon policy is employed for controlling the outer loop of a two-loop or two-layer control scheme or setup for the HVDC link. The two-loop control scheme takes advantage of the difference in speed of the dynamics of the various system variables of the HVDC link and the interconnected power systems. Model-based prediction representative of the interconnected power systems' behavior enables comparison of the future effect of different control inputs applied within the control scheme, while taking into account any physical, safety and operating constraints. It is valid for a complete operating range, e.g., it avoids performance degradation when moving away from the nominal operating point of the control scheme for a HVDC link. | 02-09-2012 |
| 20120033462 | POWER FLOW CONTROL IN A MESHED HVDC POWER TRANSMISSION NETWORK - A meshed HVDC power transmission network comprises at least three HVDC converter stations interconnected in a first closed path by at least three transmission lines. A first DC power flow control device is series connected to a first of the at least three transmission lines. That first DC power flow control device takes its power from the first transmission line and balances the DC current distribution in the first closed path. | 02-09-2012 |
| 20120033463 | POWER CONDITIONING UNIT - The present invention relates to a power conditioning unit for delivering power from a dc power source to an ac output, particularly ac voltages greater than 50 volts, either for connecting directly to a grid utility supply, or for powering mains devices independent from the mains utility supply. We describe a power conditioning unit for delivering power from a dc power source to an ac mains output, the power conditioning unit comprising an input for receiving power from said dc power source, an output for delivering ac power, an energy storage capacitor, a dc-to-dc converter having an input connection coupled to said input and an output connection coupled to the energy storage capacitor, and a dc-to-ac converter having an input connection coupled to said energy storage capacitor and an output connection coupled to said output, wherein said energy storage capacitor has a capacitance of less than twenty microfarads. | 02-09-2012 |
| 20120039099 | POWER CONDITIONING UNIT - The present invention relates to a power conditioning unit for delivering power from a dc power source to an ac output, particularly ac voltages greater than 50 volts, either for connecting directly to a grid utility supply, or for powering mains devices independent from the mains utility supply. We describe a power conditioning unit for delivering power from a dc power source to an ac mains output, the power conditioning unit comprising an input for receiving power from said dc power source, an output for delivering ac power, an energy storage capacitor, a dc-to-dc converter having an input connection coupled to said input and an output connection coupled to the energy storage capacitor, and a dc-to-ac converter having an input connection coupled to said energy storage capacitor and an output connection coupled to said output, wherein said energy storage capacitor has a capacitance of less than twenty microfarads. | 02-16-2012 |
| 20120069610 | CONVERTER - A multilevel voltage source converter for high voltage DC power transmission and reactive power compensation. The voltage source converter includes at least one phase element including a plurality of semiconductor switches to interconnect a DC voltage and an AC voltage. The voltage source converter also includes at least one auxiliary converter to act as a waveform synthesizer to modify the DC voltage presented to the DC side of the phase element. | 03-22-2012 |
| 20120081932 | CONTROL METHOD AND SYSTEM FOR REDUCING THE COMMON-MODE CURRENT IN A POWER CONVERTER - The invention relates to a control method and system intended to reduce the common-mode current in a power converter which comprises a rectifier stage ( | 04-05-2012 |
| 20120092904 | COORDINATED CONTROL OF MULTI-TERMINAL HVDC SYSTEMS - Multi-terminal HVDC systems and control methods therefore are disclosed. Methods for controlling multi-terminal HVDC systems having a plurality of converter stations may include receiving a plurality of measurements from a plurality of measurement units disposed on the HVDC system, identifying from the measurements a disruption within the HVDC system, monitoring the measurements to identify a steady-state disrupted condition for the HVDC system, calculating a new set point for at least one of the plurality of converter stations, which new set point may be based on the steady-state disrupted condition and the measurements, and transmitting the new set point to the at least one of the plurality of converter stations. In some examples, the HVDC systems may include an HVDC grid interconnecting the plurality of converter stations and a controller communicatively linked to the plurality of measurement units and the plurality of converter stations. | 04-19-2012 |
| 20120250371 | CONTROLLING AN INVERTER DEVICE OF A HIGH VOLTAGE DC SYSTEM FOR SUPPORTING AN AC SYSTEM - The invention concerns a method of controlling an inverter device, a control device as well as an inverter device and a direct current power transmission system. The direct current power transmission system is provided for connection to an AC voltage bus of an AC power system and comprises the control device and the inverter device that converts between DC power and AC power. The control device receives measurements of the voltage (V | 10-04-2012 |
| 20120281441 | CIRCUIT FOR CONVERTING A DIRECT CURRENT VOLTAGE TO AN ALTERNATING CURRENT VOLTAGE - A circuit for converting a direct current voltage into an alternating current voltage includes a buck converter, a resonant DC voltage/DC voltage converter, a DC voltage/AC voltage inverter, and a DC link capacitor. The buck converter generates a DC current according to an input voltage generated by a voltage source operating at an optimal operation point. The resonant DC voltage/DC voltage converter converts the input voltage to a DC voltage according to a switch clock and a resonant frequency determined by a resonant capacitor and a resonant inductance of the resonant DC voltage/DC voltage converter. The DC voltage/AC voltage inverter converts the DC voltage and outputs an AC voltage to an AC power supply network. The DC link capacitor adjusts power outputted by the DC voltage/AC voltage converter to regulate the DC voltage. | 11-08-2012 |
| 20120300510 | METHOD AND APPARATUS FOR CONTROLLING A DC-TRANSMISSION LINK - A method for controlling a DC-transmission link for transmitting electric power from a power production unit connected to an AC-DC converter at a first side of the DC-transmission link to a utility grid connected to a DC-AC converter at a second side of the DC-transmission link is provided. The method includes: obtaining a DC voltage signal indicative of a DC voltage at the DC transmission link; controlling the AC-DC converter such that an AC voltage at an AC side of the AC-DC converter is adjusted based on the DC voltage signal. Further, an apparatus for controlling a DC-transmission link is provided. | 11-29-2012 |
| 20120327693 | HIGH VOLTAGE DIRECT CURRENT GENERATION AND TRANSMISSION BY A WIND TURBINE - A wind turbine including a synchronous generator that converts rotary motion of a hub or rotor of the wind turbine to a variable frequency alternating current (AC) power. The wind turbine further includes a primary power system located within the wind turbine that transforms the variable frequency AC power to high voltage direct current (HVDC) power and provides the HVDC power to a load over an HVDC transmission line. A method corresponding to the flow of power through the wind turbine and a wind park comprised of a plurality of the wind turbines are also provided. | 12-27-2012 |
| 20130010504 | POWER CONVERTER AND INTEGRATED DC CHOKE THEREFOR - A power conversion system and a DC link choke therefore are presented, in which a continuous core structure is provided with first and second legs around which four or more windings are located, with one or more shunt structures providing a magnetic flux path between intermediate portions of the first and second legs. | 01-10-2013 |
| 20130044522 | LOW WEIGHT 3-PHASE 5-OUTPUT WIRE POWER CONVERSION SYSTEM FOR MICRO-GRID - A power conversion system eliminates output transformers and replaces them with a zig-zag transformer and a filter that provides a 3-phase 5-wire system with significantly reduced weight and size as compared with conventional systems. The zig-zag transformer may have a low zero sequence impedance. The power conversion system also ensures operational safety by detecting various types of ground faults. | 02-21-2013 |
| 20130128629 | HYBRID 2-LEVEL AND MULTILEVEL HVDC CONVERTER - A voltage source converter is used in high voltage direct current power transmission and reactive power compensation. The voltage source converter comprises first and second DC terminals for connection in use to a DC network, three phase elements and at least one auxiliary converter connected between the first and second DC terminals, each phase element including a plurality of primary switching elements and at least one AC terminal for connection in use to a respective phase of a multi-phase AC network, the plurality of primary switching elements being controllable in use to facilitate power conversion between the AC and DC networks, the or each auxiliary converter being operable in use to act as a waveform synthesizer to modify a first DC voltage presented to the DC network so as to minimise ripple in the DC voltage. | 05-23-2013 |
| 20130128630 | METHOD OF CONTROLLING THE POWER INPUT TO A HVDC TRANSMISSION LINK - Disclosed is a method of controlling the power input to a HVDC transmission link, which HVDC transmission link is connected to an AC power plant via a first voltage source converter and to AC grid via a second voltage source converter, which method includes using the second voltage source converter to perform voltage control of the HVDC transmission link during a no-fault mode of operation of the grid; monitoring a HVDC transmission link parameter to detect an unbalanced fault; and using the first voltage source converter to regulate the output of the AC power plant on the basis of the monitored HVDC transmission link parameter in the event of an unbalanced fault. Also described are a control module for controlling the power input to a HVDC transmission link; a voltage source converter for a power plant; and a power generation and transmission arrangement. | 05-23-2013 |
| 20130128631 | NEUTRAL POINT CLAMPED CONVERTER CONTROL SYSTEMS AND METHODS - A control system includes first and second fundamental control units for generating first and second fundamental commands, and a compensation control unit. The compensation control unit includes first and second calculation elements and a comparator for comparing first and second modulation indexes. When the first modulation index is less than the second modulation index, the first calculation element generates a first source-side compensation command. When the first source-side compensation command is not sufficient to balance the neutral point voltage, the first calculation element further generates a first line-side compensating command. When the first modulation index is greater than the second modulation index, the second calculation element generates a second line-side compensation command. When the second line-side compensation command is not sufficient to balance the neutral point voltage, the second calculation element further generates a second source-side compensating command. | 05-23-2013 |
| 20130141950 | POWER CONVERTER AND INTEGRATED DC CHOKE THEREFOR - A power conversion system and a DC link choke therefore are presented, in which a continuous core structure is provided with first and second legs around which four or more windings are located, with one or more shunt structures providing a magnetic flux path between intermediate portions of the first and second legs. | 06-06-2013 |
| 20130170255 | APPARATUS FOR CONTROLLING THE ELECTRIC POWER TRANSMISSION IN A HVDC POWER TRANSMISSION SYSTEM - An apparatus for controlling the electric power transmission in a high voltage direct current, HVDC, power transmission system includes at least one HVDC transmission line for carrying direct current, DC. The apparatus includes a first converter for converting alternating current, AC, to direct current and/or direct current to alternating current, and a second converter for converting direct current to alternating current and/or alternating current to direct current, each of the first and second converters having an AC side for output and/or input of alternating current and a DC side for output and/or input of direct current. The first converter is connectable via its DC side to the HVDC transmission line, the AC side of the second converter is connected to the AC side of the first converter, and the second converter is connectable via its DC side to a DC source. The apparatus is adapted to control the direct current of the HVDC transmission line by introducing a DC voltage in series with the HVDC transmission line. A HVDC power transmission system includes the above-mentioned apparatus. | 07-04-2013 |
| 20130182467 | CONVERTER - A voltage source converter comprising three phase elements defining a star connection in which a first end of each phase element is connected to a common junction; at least two converter limbs, each converter limb including first and second DC terminals for connection in use to a DC network and an AC terminal connected in series with a second end of a phase element, each converter limb defining first and second limb portions, including a chain-link converter, each chain-link converter including chain-link modules; and a third DC terminal connected to the common junction of the star connection to define an auxiliary connection, wherein in use a current is injected into the auxiliary connection to modify a voltage of each chain-link module in each limb portion. | 07-18-2013 |
| 20130208514 | CONVERTER FOR HVDC TRANSMISSION AND REACTIVE POWER COMPENSATION - A power electronic converter for use in high voltage direct current power transmission and reactive power compensation comprises a plurality of switching elements interconnecting in use a DC network and one or more AC networks, the plurality of switching elements being controllable in use to facilitate power conversion between the AC and DC networks, wherein in use, the plurality of switching elements are controllable to form one or more short circuits within the power electronic converter so as to define one or more primary current flow paths, the or each primary current flow path including a respective one of the AC networks and the power electronic converter and bypassing the DC network. | 08-15-2013 |
| 20130258724 | HIGH VOLTAGE DIRECT CURRENT SYSTEM - A high voltage direct current system is presented. The system includes at least three high voltage direct current terminals. Furthermore, the system include at least two transmission lines configured to operatively couple the at least three high voltage direct current terminals. Moreover, the system includes a power flow control device operatively coupled to at least one end of one or more of the at least two transmission lines and at least one of a local grid and another power flow control device. Methods to perform the method for power flow control are also presented. | 10-03-2013 |
| 20130279210 | Power Conditioning Units - We describe a power conditioning unit with maximum power point tracking (MPPT) for a dc power source, in particular a photovoltaic panel. A power injection control block has a sense input coupled to an energy storage capacitor on a dc link and controls a dc-to-ac converter to control the injected mains power. The power injection control block tracks the maximum power point by measuring a signal on the dc link which depends on the power drawn from the dc power source, and thus there is no need to measure the dc voltage and current from the dc source. In embodiments the signal is a ripple voltage level and the power injection control block controls an amplitude of an ac current output such that an amount of power transferred to the grid mains is dependent on an amplitude of a sinusoidal voltage component on the energy storage capacitor. | 10-24-2013 |
| 20130279211 | Modular Multilevel Converter - A power electronic converter for use in high voltage direct current power transmission and reactive power compensation includes at least one converter limb, which includes first and second DC terminals and an AC terminal. Each converter limb defines first and second limb portions connected in series between the AC terminal and a respective one of the first and second DC terminals. Each limb portion includes a chain-link converter connected in series with at least one primary switching element. Each chain-link converter includes a plurality of modules connected in series, and each module includes at least one secondary switching element connected to at least one energy storage device. Each primary switching element in each limb portion of a respective converter limb selectively defines a circulation path which carries a DC circulation current to regulate the energy level of at least one energy storage device in a respective chain-link converter. | 10-24-2013 |
| 20130301313 | HVDC SYSTEM AND METHOD TO CONTROL A VOLTAGE SOURCE CONVERTER IN A HVDC SYSTEM - A method to control a voltage source converter (CON | 11-14-2013 |
| 20130322131 | CASCADED CONVERTER STATION AND CASCADED MULTI-TERMINAL HVDC POWER TRANSMISSION SYSTEM - A cascade converter station and a multi-end cascade high-voltage direct current (HVDC) power transmission system. The converter station includes a low-voltage end converter station ( | 12-05-2013 |
| 20140092650 | POWER TRANSMISSION SYSTEMS - An offshore wind farm includes a plurality of wind turbines connected to an onshore converter station by means of a distributed power transmission system. The power transmission system includes a series of offshore converter platforms distributed within the wind farm. Each converter platform includes a busbar carrying an ac voltage for the converter platform and to which the wind turbines are connected. Each converter platform also includes one or more converter transformers connected to the busbar and a series of one or more converter modules. The power transmission system includes dc transmission lines which deliver generated power back to the onshore converter station. | 04-03-2014 |
| 20140133196 | CONVERTER - A power electronic converter, for use in high voltage direct current power transmission and reactive power compensation, comprises at least one converter limb including first and second terminals being connectable to a DC network and a third terminal, the or each converter limb defining first and second limb portions connected in series between the third terminal and a respective one of the first and second terminals, each limb portion including a chain-link converter, each chain-link converter including a plurality of modules connected in series, each module including at least one primary switching element connected to at least one energy storage device, each converter limb being controllable to selectively define a circulation path carrying an AC circulation current for presentation to the DC network to minimise DC ripple in a DC voltage presented to the DC network. | 05-15-2014 |
| 20140146582 | HIGH VOLTAGE DIRECT CURRENT (HVDC) CONVERTER SYSTEM AND METHOD OF OPERATING THE SAME - A high voltage direct current (HVDC) converter system includes at least one line commutated converter (LCC) and at least one current controlled converter (CCC). The at least one LCC and the at least one CCC are coupled in parallel to at least one alternating current (AC) conduit and are coupled in series to at least one direct current (DC) conduit. The at least one LCC is configured to convert a plurality of AC voltages and currents to a regulated DC voltage of one of positive and negative polarity and a DC current transmitted in only one direction. The at least one current controlled converter (CCC) is configured to convert a plurality of AC voltages and currents to a regulated DC voltage of one of positive and negative polarity and a DC current transmitted in one of two directions. | 05-29-2014 |
| 20140146583 | HVDC CONVERTER WITH NEUTRAL-POINT CONNECTED ZERO-SEQUENCE DUMP RESISTOR - A power electronic converter ( | 05-29-2014 |
| 20140177292 | MULTILEVEL VALVE FOR VOLTAGE SOURCED CONVERTER TRANSMISSION - A method for transforming electric power from high voltage AC voltage and AC current to high voltage DC voltage and DC current and from high voltage DC voltage and DC current to high voltage AC voltage and AC current. The method includes passing the power through voltage sourced converters whose legs are comprised all or in part with 3 step ladder bridge modules connected in series. | 06-26-2014 |
| 20140233277 | DIRECT CURRENT POWER DELIVERY SYSTEM AND METHOD - A power transmission system includes a first unit for carrying out the steps of receiving high voltage direct current (HVDC) power from an HVDC power line, generating an alternating current (AC) component indicative of a status of the first unit, and adding the AC component to the HVDC power line. Further, the power transmission system includes a second unit for carrying out the steps of generating a direct current (DC) voltage to transfer the HVDC power on the HVDC power line, wherein the HVDC power line is coupled between the first unit and the second unit, detecting a presence or an absence of the added AC component in the HVDC power line, and determining the status of the first unit based on the added AC component. | 08-21-2014 |
| 20140247629 | CONVERTERS - A converter, and in particular a current source converter, including a bridge having an AC terminal for each of one or more AC lines, and first and second DC terminals. A converter arm is connected between each respective AC terminal and the first DC terminal, and between each respective AC terminal and the second DC terminal. Each converter arm includes a first power semiconductor switching device capable of being turned ‘on’ and ‘off’ by gate control and having a recovery time. The converter is adapted to be operated in one or more inverting modes. | 09-04-2014 |
| 20140268926 | HIGH VOLTAGE DIRECT CURRENT (HVDC) CONVERTER SYSTEM AND METHOD OF OPERATING THE SAME - A high voltage direct current (HVDC) converter system includes a line commutated converter (LCC) configured to convert a plurality of AC voltages and currents to a regulated DC voltage of one of positive and negative polarity and a DC current transmitted in only one direction. The HVDC converter system also includes a buck converter configured to convert a plurality of AC voltages and currents to a regulated DC voltage of one of positive and negative polarity and a DC current transmitted in one of two directions. The LCC and the buck converter are coupled in parallel to an AC conduit and are coupled in series to a DC conduit. The HVDC converter system further includes a filtering device coupled in parallel to the buck converter through the AC conduit. The filtering device is configured to inject AC current having at least one harmonic frequency into the AC conduit. | 09-18-2014 |
| 20140268927 | VOLTAGE CONVERTER SYSTEMS - A voltage converter system includes a first DC-AC voltage converter that converts a first DC voltage signal to a first AC voltage signal. A DC link converts the first AC voltage signal to a second DC voltage signal. A second DC-AC voltage converter converts the second DC voltage signal to a second AC voltage signal. In another configuration a DC-AC voltage converter converts a DC voltage signal to a first AC voltage signal. An AC-AC voltage converter converts the first AC voltage signal to a second, lower-frequency AC voltage signal. In yet another configuration a first voltage converter portion converts a DC voltage signal to pulses of DC voltage. A second voltage converter portion converts the pulses of DC voltage to a relatively low-frequency AC voltage signal. The voltage converter system is selectably configurable as a DC-AC voltage converter or an AC-DC voltage converter. | 09-18-2014 |
| 20140307488 | CONTROLLER FOR CONTROLLING A POWER CONVERTER - A controller is provided for controlling a power converter that converts electrical input power of a wind turbine into electrical output power provided to a grid. The power converter includes grid-side and turbine-side converter parts. The controller comprises an input terminal for receiving a voltage reference signal associated with a predefined grid voltage and a frequency reference signal associated with a predefined grid frequency, and a network bridge controller adapted to control power conversion of the grid-side converter part. The network bridge controller includes a modulator for modulating gate drive command signals in the grid-side converter part based on a reference voltage and a reference angle derived from the voltage reference signal and the frequency reference signal. The modulator is adapted to modulate the gate drive command signals to maintain the predefined grid voltage and the predefined grid frequency in the power converter in case of failure within the grid. | 10-16-2014 |
| 20140347897 | HIGH VOLTAGE DIRECT CURRENT TRANSMISSION AND DISTRIBUTION SYSTEM - A direct current to alternating current inverter sub-system is for a HVDC distribution system. The DC to AC inverter sub-system includes an enclosure and a DC to DC galvanically isolated buck converter having a DC input electrically connectable to a HVDC cable and a DC output. A DC to AC inverter includes a DC input electrically connected to the DC output of the DC to DC galvanically isolated buck converter and an AC output electrically connectable to an AC transmission line. The DC to AC inverter is mounted in an enclosure with the DC to DC galvanically isolated buck converter, in order that the DC output of the DC to DC galvanically isolated buck converter is directly electrically connected within the enclosure to the DC input of the DC to AC inverter. | 11-27-2014 |
| 20140347898 | MODULAR MULTI-LEVEL POWER CONVERSION SYSTEM WITH DC FAULT CURRENT LIMITING CAPABILITY - A power converter module is provided. The power converter module includes a first converter leg and a second converter leg. The first converter leg includes a first switching unit and a second switching unit coupled in series. The second switching unit is disposed in a reverse orientation with respect to an orientation of the first switching unit. The second converter leg includes a third switching unit and a diode coupled in series. The third switching unit is disposed in a reverse orientation with respect to the orientation of the first switching unit. The power converter also includes a first energy storage device operatively coupled between the first converter leg and the second converter leg. The power converter module further includes a second energy storage device operatively coupled between the first converter leg and the second converter leg. | 11-27-2014 |
| 20140362618 | POWER ELECTRONIC CONVERTER - A power electronic converter for high/medium voltage direct current power transmission and reactive power compensation comprises a primary converter unit and an auxiliary converter unit, the primary converter unit including at least one primary converter limb including first and second DC terminals for connection in use to a DC network and an AC terminal, the or each primary converter limb defining first and second limb portions, each limb portion including at least one primary module, the or each primary module including at least one primary switching element connected to an energy storage device, the auxiliary converter unit including at least one auxiliary converter limb including at least one auxiliary module including a plurality of auxiliary switching elements connected to the energy storage device of a corresponding primary module in the first limb portion of a respective primary converter limb, the primary switching elements of the primary modules being controllable in use to switch the respective energy storage device in and out of circuit to generate a voltage waveform at the respective AC terminal. | 12-11-2014 |
| 20140362619 | HVDC Converter - An AC-AC converter system includes transformer arrangements and HVDC converter units on primary and secondary sides of the system, respectively. The system exhibits first and second three-phase AC networks, and the converter units are interconnected via a DC connection. By integrating at least part of two transformer arrangements in one transformer unit, a cost efficient transformer configuration can be achieved. | 12-11-2014 |
| 20150009724 | Solar Power Conditioning Unit - The present invention relates to a power conditioning unit for delivering power from a dc power source to an ac output, particularly ac voltages greater than 50 volts, either for connecting directly to a grid utility supply, or for powering mains devices independent from the mains utility supply. We describe a power conditioning unit for delivering power from a dc power source to an ac mains output, the power conditioning unit comprising an input for receiving power from said dc power source, an output for delivering ac power, an energy storage capacitor, a dc-to-dc converter having an input connection coupled to said input and an output connection coupled to the energy storage capacitor, and a dc-to-ac converter having an input connection coupled to said energy storage capacitor and an output connection coupled to said output, wherein said energy storage capacitor has a capacitance of less than twenty microfarads. | 01-08-2015 |
| 20150009725 | POWER CONVERSION CIRCUIT - A converter to which an alternating current is inputted from an AC power supply rectifies the alternating current to output it to a DC link. An inverter is connected through the DC link to the converter and converts a direct current into an alternating current to output it to a load. A leakage current detector outputs a detection current corresponding to a leakage current leaking from the load. A compensating current output end is connected to a location where the leakage current leaks, and outputs a compensating current compensating for the leakage current in response to the detection current. A switch sets whether to input the detection current to the compensating current output section or not. | 01-08-2015 |
| 20150124496 | METHOD FOR CHARGING A DC LINK OF A WIND TURBINE POWER ELECTRONIC CONVERTER - The present invention relates to a method for charging a DC link of a power converter included in a wind turbine generator, the wind turbine generator comprising a generator side converter connected to an electrical generator and a grid side converter connectable, or connected, to an electrical grid through a grid circuit breaker, and a converter controller arranged to control at least the DC link, the DC link having a DC voltage level, the wind turbine generator comprising a wind turbine rotor arranged to rotate the electrical generator, wherein the method comprises rotating the wind turbine rotor whereby the electrical generator generates electrical power, rectifying the electrical power through at least one diode of the generator side converter in order to pre-charge the DC link to a DC voltage level, closing the grid circuit breaker when the DC voltage level is greater than a threshold level. The invention also relates to a wind turbine generator with a converter controller for controlling pre-charging of a DC link. | 05-07-2015 |
| 20150131342 | MULTI TERMINAL HVDC CONTROL - An exemplary Multi-Terminal High Voltage Direct Current (MTDC) system includes at least three terminals, where each terminal including a Voltage Source Converter (VSC) controlled by a VSC controller. A method for controlling the MTDC system includes providing a converter schedule including at least one of a desired power flow value and a DC voltage; determining, by a MTDC master controller, a present state of the MTDC system including a dynamic topology of the MTDC system; determining, by the MTDC master controller, based on the present state of the MTDC system, based on the schedule and based on MTDC system constraints, VSC controller parameters including droop settings for local control by the VSC controllers; and transmitting the VSC controller parameters to the VSC controllers. | 05-14-2015 |
| 20150295507 | THYRISTOR BASED VOLTAGE SOURCE CONVERTER - A voltage source converter includes a number of valves, the valves including switching elements with anti-parallel diodes provided in a bridge for switching between two states. The bridge is provided in at least one phase leg that stretches between two direct current poles and has at least one midpoint, which is connected to an alternating current terminal. The switching element of at least one valve is a thyristor. The converter further includes a commutation cell associated with the valve, where the commutation cell is controllable to reverse-bias the valve if it is to stop conducting current. | 10-15-2015 |
| 20150303819 | SYSTEM AND METHOD FOR POWER CONVERSION - A method used to control the operation of a converting device such that it can provide multi-level output voltage for loads. This method comprises at least the steps of: determine whether the load which the converter is providing electricity for is operating under the first condition or the second condition; generate the first pulse signal after determining that this load is operating under the first condition, select at least one of at least three different current paths, such that when the converter is selecting any of the current paths, it can provide output voltage at the same level; as well as generate the second pulse signal after determining that this load is operating under the second condition, such that the converter can perform the regular energy conversion operations. | 10-22-2015 |
| 20150311813 | TRANSFORMER APPARATUS - An apparatus for connecting a converter to an AC voltage grid has a grid connection for connection to the AC voltage grid and a converter connection for connection to the converter. The grid connection and the converter connection can be connected to one another via two transformers that are connected in parallel with one another and which, in addition to a primary winding and a secondary winding, are equipped with a tertiary winding. At least one switch is connected in series with each transformer. A connection unit is connected to the tertiary windings of each of the transformers and is configured to connect the tertiary windings to one another. | 10-29-2015 |
| 20150333642 | HIGH VOLTAGE DIRECT CURRENT TRANSMISSION SYSTEM AND CONTROLLING METHOD THEREOF - Provided is a high voltage direct current transmission system including a power transmission part converting AC power into DC power; a power receiving part converting DC power into AC power; and a DC power transmission part transferring the DC power converted in the power transmission part to the power receiving part, wherein one of the power transmission part and the power receiving part includes a measuring part measuring an AC voltage; an AC voltage control unit generating a first reactive power control signal based on the measured AC voltage and a reference AC voltage; a reactive power control unit generating a second reactive power control signal based on the first reactive power control signal and a reference reactive power signal; and a power control unit controlling reactive power of the power transmission part or the power receiving part based on the second reactive power control signal. | 11-19-2015 |
| 20150333643 | HVDC TRANSMISSION SYSTEM - A high voltage direct current (HVDC) transmission system is provided. The high voltage direct current (HVDC) transmission system includes: an integrated measurement panel; and an HVDC transmission device, wherein the HVDC transmission device is configured to: receive, from the integrated measurement panel, compensation values for compensating for the voltage values output through the first to Nth potential transformers, compensate for the voltage values output through the first to Nth potential transformers by using the received compensation values, and measure the actual voltage values by using the compensated voltage values. | 11-19-2015 |
| 20150333644 | APPARATUS AND METHOD FOR DESIGN OF HIGH VOLTAGE DIRECT CURRENT TRANSMISSION SYSTEM - Provided is an apparatus for an insulation design. The apparatus for an insulation design, which performs the insulation design of a high voltage direct current (HVDC) transmission system, includes an HVDC transmission system operation information acquisition unit, a design specification acquisition unit, a design requirement acquisition unit, and an HVDC transmission system design unit. | 11-19-2015 |
| 20150333645 | APPARATUS AND METHOD FOR INSULATION DESIGN OF HIGH VOLTAGE DIRECT CURRENT TRANSMISSION SYSTEM - Provided is an apparatus for an insulation design. The apparatus for the insulation design, which performs the insulation design of a high voltage direct current (HVDC) transmission system, includes a first insulation modeling unit, an insulation level calculation unit, a second insulation modeling unit, and a rated insulation level calculation unit. | 11-19-2015 |
| 20150333646 | APPARATUS AND METHOD FOR INSULATION DESIGN OF HIGH VOLTAGE DIRECT CURRENT TRANSMISSION SYSTEM - Provided is an apparatus for an insulation design. The apparatus for the insulation design, which performs the insulation design of a high voltage direct current (HVDC) transmission system includes a contingency state voltage calculation unit, a case analysis performance unit, and a rated insulation level calculation unit. | 11-19-2015 |
| 20150333647 | HIGH VOLTAGE DIRECT CURRENT TRANSMISSION SYSTEM AND CONTROL METHOD THEREOF - A high voltage direct current (HVDC) transmission system is provided. The high voltage direct current (HVDC) transmission system includes: a rectifier converting alternating current (AC) power into DC power; an inverter converting the DC power into the AC power; a DC transmission line transmitting, to the inverter, the DC power obtained through conversion by the rectifier; a first active power measurement unit measuring first active power input to the rectifier; a second active power measurement unit measuring second active power output from the inverter; and a first control unit detecting an abnormal voltage state on the DC transmission line based on the first and second active power measured. | 11-19-2015 |
| 20150333648 | HIGH VOLTAGE DIRECT CURRENT TRANSMISSION SYSTEM AND CONTROL METHOD THEREOF - A high voltage direct current (HVDC) transmission system is provided. The high voltage direct current (HVDC) transmission system includes a rectifier converting alternating current (AC) power into DC power; an inverter converting the DC power into the AC power; DC transmission lines W | 11-19-2015 |
| 20150333649 | MODULAR MULTI-LEVEL CONVERTER - Provided is a modular multi-level converter including a plurality of sub-modules including switching elements, a plurality of sub-control units respectively controlling the plurality of switching elements included in the plurality of sub-modules, and a central control unit which determines switching operation conditions of the plurality of sub-modules, and transmits control signals corresponding to the determined switching operation conditions to the plurality of sub-control units. Each of the plurality of sub-control units acquires state information on the sub-module controlled thereby and transmits the acquired state information to the central control unit. | 11-19-2015 |
| 20150333650 | DATA PROCESSING DEVICE AND METHOD FOR HIGH VOLTAGE DIRECT CURRENT TRANSMISSION SYSTEM - A data processing device is provided. The data processing device in a high voltage direct current (HVDC) transmission system includes a measurement module measuring a voltage or current for one or more points in the HVDC system; and a data processing and control unit generating measurement data units using measurement values measured at the measurement module and performing serial transmission on the generated measurement data units through time division multiplexing (TDM), wherein the data processing and control unit includes a plurality of data unit generation parts, and each of the plurality of data unit generation parts outputs a transmission completion signal representing that the transmission of a measurement data unit is completed. | 11-19-2015 |
| 20150333651 | DATA PROCESSING DEVICE AND METHOD FOR HIGH VOLTAGE DIRECT CURRENT TRANSMISSION SYSTEM - A data processing device in a high voltage direct current (HVDC) transmission system is provided. The data processing device includes a measurement module measuring a voltage or current for one or more points in the HVDC system; a data processing unit generating measurement data units using measurement values measured at the measurement module; and a communication module using wavelength division multiplexing to transmit the measurement data units to the outside through one optical fiber, wherein the optical fiber includes a plurality of cores. | 11-19-2015 |
| 20150349655 | DEVICE AND METHOD FOR CONNECTING AN ELECTRIC POWER GENERATOR TO AN HVDC TRANSMISSION SYSTEM - A device for connecting an electric power generator to an HVDC transmission system is provided, the device having (a) a first unit for converting an AC output voltage from the electric power generator to a DC input voltage for the HVDC transmission system, the first unit having a transformer and a full-bridge rectifier, and (b) a second unit for generating control voltages and/or control currents in the transformer and/or in the electric power generator, the second unit having a PWM full-bridge converter adapted to receive the AC output voltage from the electric power generator or an AC voltage based on said AC output voltage. Furthermore, a system and a method are provided. | 12-03-2015 |
| 20150381069 | DATA PROCESSING DEVICE FOR HIGH VOLTAGE DIRECT CURRENT TRANSMISSION SYSTEM AND METHOD THEREOF - Provided is a data processing device of a high voltage direct current (HVDC) transmission system including: a measuring module measuring voltage and current at one or more points in the HVDC transmission system; a data processing part generating measured data units by using the measured values received from the measuring module; and a communication module transmitting the plurality of measured data units to the outside by using a wavelength division multiplexing method. | 12-31-2015 |
| 20160006243 | HUB - A hub for transferring power between DC systems. The hub comprises N modules, each for connection to a respective DC system of voltage V | 01-07-2016 |
| 20160013649 | CONTROL CIRCUIT | 01-14-2016 |
| 20160013653 | CONVERTER STATION WITH DIODE RECTIFIER | 01-14-2016 |
| 20160036341 | POWER GRID FREQUENCY FLEXIBLE OPERATION SYSTEM AND METHOD USING THE SAME - A power grid frequency flexible operation system is provided. The system comprises a generating unit, which includes a base-load unit and a peak-load unit; a high voltage direct-current (HVDC) transmission unit, which transmits the power generated in the generating unit as direct current (DC) power; and a load, which is supplied with the power generated by the generating unit; wherein the high-voltage direct current (HVDC) transmission unit comprises a converter, which transforms to direct current (DC) power, alternating current (AC) power generated in the generating unit and having a first frequency variation allowance range; an inverter, which is connected to the converter and transforms the direct current (DC) power to alternating current (AC) power having a second frequency variation allowance range, wherein the first frequency variation allowance range is larger than the second frequency variation allowance range. | 02-04-2016 |
| 20160036342 | POWER CONVERSION DEVICE - Semiconductor switching elements are individually inserted between a plurality of power conversion units provided in parallel with each other through a DC link portion and a DC power supply unit for supplying DC power to each of the power conversion units to restrict the DC power supplied to the respective power conversion units. A control circuit monitors a short-circuit current occurring in each of the power conversion units and turns off the semiconductor switching element connected to the power conversion unit where the short-circuit current flows to stop the power supplied to the power conversion unit. | 02-04-2016 |
| 20160049880 | HIGH-VOLTAGE DIRECT CURRENT CONVERTER - The present invention relates to a high-voltage direct current (HVDC) converter comprising: a 12-pulse diode rectifier having two three-phase bridge diode rectifiers connected in series to rectify, to 12 pulses, alternating current (AC) power inputted from a point of connection on the sea; and a voltage-source converter connected in series to a lower end of the 12-pulse diode rectifier, wherein the voltage-source converter controls a voltage of the AC power inputted from the point of connection on the sea and a DC link voltage of the voltage-source converter. | 02-18-2016 |
| 20160072400 | Universal Power Conversion Methods - Methods and systems for transforming electric power between two or more portals. Any or all portals can be DC, single phase AC, or multi-phase AC. Conversion is accomplished by a plurality of bi-directional conducting and blocking semiconductor switches which alternately connect an inductor and parallel capacitor between said portals, such that energy is transferred into the inductor from one or more input portals and/or phases, then the energy is transferred out of the inductor to one or more output portals and/or phases, with said parallel capacitor facilitating “soft” turn-off, and with any excess inductor energy being returned back to the input. Soft turn-on and reverse recovery is also facilitated. Said bi-directional switches allow for two power transfers per inductor/capacitor cycle, thereby maximizing inductor/capacitor utilization as well as providing for optimum converter operation with high input/output voltage ratios. Control means coordinate the switches to accomplish the desired power transfers. | 03-10-2016 |
| 20160072407 | CONVERTER - A voltage source converter includes a converter limb having limb portions separated by an AC terminal and extending between DC terminals, each limb portion including a primary switching element to switch the limb portion into and out of circuit. The converter further includes an auxiliary limb. The primary switching element of each limb portion is switchable to switch the auxiliary limb into and out of circuit with the corresponding limb portion. The converter further includes a control unit to, in one mode, inject a circulation current that flows in one direction in one of the limb portions and minimize a current flowing in the opposite direction in that limb portion. Each primary switching element switches the respective limb portion into or out of circuit following the minimization of the limb portion current by the circulation current. | 03-10-2016 |
| 20160079879 | Method For Controlling Of A Modular Converter - A method for controlling a modular converter, having a plurality of M converter cells, including an active AC-to-DC converter operable in one of a plurality of modes; a DC-to-DC converter; a secondary side of said AC-to-DC converter and a primary side of said DC-to-DC converter connected in parallel with a DC-link capacitor, wherein the primary sides of the converter cells are connected in series, with a first converter cell connected to a line, preferably a medium voltage line, providing an AC line voltage an M-th converter cell connected to a ground; operated by a method placing the converters in bypassed, active or diode mode. | 03-17-2016 |
| 20160099652 | HIGH VOLTAGE DIRECT CURRENT TRANSMISSION SYSTEM - A high voltage direct current (HVDC) transmission system is provided. The high voltage direct current (HVDC) transmission system includes: a first power transceiving part consuming power generated by a power generation part, storing the generated power, and outputting the generated power or stored power to a second power transceiving part; a second power transceiving part consuming power generated by a power generation part, storing the generated power and outputting the generated power or stored power to the first power transceiving part; and a control part controlling the power transmission and reception of the first power transceiving part and the second power transceiving part. | 04-07-2016 |
| 20160099653 | POWER FLOW CONTROLLER WITH A FRACTIONALLY RATED BACK-TO-BACK CONVERTER - A power flow controller with a fractionally rated back-to-back (BTB) converter is provided. The power flow controller provide dynamic control of both active and reactive power of a power system. The power flow controller inserts a voltage with controllable magnitude and phase between two AC sources at the same frequency; thereby effecting control of active and reactive power flows between the two AC sources. A transformer may be augmented with a fractionally rated bi-directional Back to Back (B TB) converter. The fractionally rated BTB converter comprises a transformer side converter (TSC), a direct-current (DC) link, and a line side converter (LSC). By controlling the switches of the BTB converter, the effective phase angle between the two AC source voltages may be regulated, and the amplitude of the voltage inserted by the power flow controller may be adjusted with respect to the AC source voltages. | 04-07-2016 |
| 20160111967 | POWER CELL BYPASS METHOD AND APPARATUS FOR MULTILEVEL INVERTER - Multilevel inverters, power cells and bypass methods are presented in which a power cell switching circuit is selectively disconnected from the power cell output, and a bypass which is closed to connect first and second cell output terminals to selectively bypass a power stage of a multilevel inverter, with an optional AC input switch to selectively disconnect the AC input from the power cell switching circuit during bypass. | 04-21-2016 |
| 20160118907 | SEMICONDUCTOR SWITCHING STRING - A semiconductor switching string includes a plurality of series-connected semiconductor switching assemblies, each having a main semiconductor switching element that includes first and second connection terminals. The main semiconductor switching element also has an auxiliary semiconductor switching element electrically connected between the first and second connection terminals. Each semiconductor switching assembly also includes a control unit configured to switch on a respective auxiliary semiconductor switching element to selectively create an alternative current path between the first and second connection terminals whereby current is diverted to flow through the alternative current path to reduce the voltage across the corresponding main semiconductor switching element. The or each control unit is further configured to switch on the auxiliary semiconductor switching element when the voltage across the corresponding main semiconductor switching element differs from a voltage reference derived from the voltage across all of the main semiconductor switching elements. | 04-28-2016 |
| 20160134118 | HIGH VOLTAGE DIRECT CURRENT TRANSMISSION AND DISTRIBUTION SYSTEM - A direct current to alternating current inverter sub-system is for a HVDC distribution system. The DC to AC inverter sub-system includes an enclosure and a DC to DC galvanically isolated buck converter having a DC input electrically connectable to a HVDC cable and a DC output. A DC to AC inverter includes a DC input electrically connected to the DC output of the DC to DC galvanically isolated buck converter and an AC output electrically connectable to an AC transmission line. The DC to AC inverter is mounted in an enclosure with the DC to DC galvanically isolated buck converter, in order that the DC output of the DC to DC galvanically isolated buck converter is directly electrically connected within the enclosure to the DC input of the DC to AC inverter. | 05-12-2016 |
| 20160149507 | SYSTEM AND METHOD FOR UNIFIED COMMON MODE VOLTAGE INJECTION - A power conversion system includes at least one multi-level power converter and a controller coupled to the at least one multi-level power converter. The controller includes a first CMV injection module and a second CMV injection module. The first CMV injection module generates a first CMV signal for modifying at least one voltage command to achieve a first function in association with operation of the power conversion system. The second CMV injection module generates a second CMV signal based at least in part on a three-level CMV limit either for modifying the at least one voltage command or for further modifying the at least one modified voltage command to achieve a second function in association with operation of the power conversion system. | 05-26-2016 |
| 20160149508 | INSULATION DESIGN APPARATUS OF HIGH VOLTAGE DIRECT CURRENT TRANSMISSION SYSTEM - An insulation design apparatus performing the insulation design of a high voltage direct current (HVDC) transmission system is provided. The insulation design apparatus includes a first insulation model generation unit; a second insulation model generation unit; an insulation verification unit, wherein the second insulation model generation unit selects the positions of each facility, device and arrester of the HVDC transmission system through a system single line diagram to select a representative facility in the HVDC transmission system, divides the HVDC transmission system into the plurality of regions based on the selected representative facility, and generates an insulation model for each region. | 05-26-2016 |
| 20160156276 | SYSTEM AND METHOD FOR OPERATING POWER CONVERTERS | 06-02-2016 |
| 20160164296 | MODULE - A module for use in a voltage source converter includes: first and second terminals; an energy storage device; at least one switching element to switch the energy storage device into or out of circuit with the terminals to selectively provide a voltage source; and a voltage-limiting component and/or a resistive element. The switching element(s) are switchable to selectively form a current path that passes through the voltage-limiting component and/or the resistive element and are further switchable to selectively switch the energy storage device into or out of circuit with the voltage-limiting component and/or the resistive element. The module includes electrical blocks including first and second pairs of electrical blocks connected in parallel with the energy storage device in a full-bridge arrangement. Each of the electrical blocks include a switching element, and one of the electrical blocks includes the voltage-limiting component and/or the resistive element. | 06-09-2016 |
| 20160172990 | A POWER CONVERTER | 06-16-2016 |
| 20160172991 | CONVERTER ARRANGEMENT | 06-16-2016 |
| 20160197558 | POWER CONVERTER | 07-07-2016 |
| 20160197559 | POWER CONVERSION SYSTEM AND CONTROLLING METHOD THEREOF AND WIND TURBINE POWER GENERATION SYSTEM | 07-07-2016 |
| 20160254669 | COORDINATED CONTROL OF MULTI-TERMINAL HVDC SYSTEMS | 09-01-2016 |
