For Transfer Of Power Via A High Voltage D.c. Link (i.e., Hvdc Transmission System) Patents (Class 363/35)
  • Patent number: 10570885
    Abstract: Controlling a wind turbine during a grid fault where the grid voltage drops below a nominal grid voltage. After detection of a grid fault, the total current limit for the power converter output is increased to a total maximum overload current limit. Depending on whether active or reactive current generation is prioritized, an active or reactive current reference is determined. The active current reference is determined in a way so that a reduction in active power production due to the grid voltage drop is minimized and based on the condition that the vector-sum of the active output current and the reactive output current is limited according to the total maximum overload current limit, and a maximum period of time is determined in which the power converter can be controlled based on the active/reactive current references. Afterwards the power converter is controlled based on the active and reactive current references.
    Type: Grant
    Filed: September 27, 2018
    Date of Patent: February 25, 2020
    Assignee: VESTAS WIND SYSTEMS A/S
    Inventors: Ciprian Biris, Uffe C. Merrild, Leif Svinth Christensen, Martin Ansbjerg Kjær
  • Patent number: 10574055
    Abstract: A system includes a converter configured to be coupled between an energy storage unit and a grid and a control circuit configured to detect frequency and voltage variations of the grid and to responsively cause the converter to transfer power and reactive components to and/or from the grid. The control circuit may implement a power control loop having an inner frequency control loop and a reactive component control loop having an inner voltage control loop. The control circuit may provide feedforward from the inner frequency control loop to the inner voltage control loop to inhibit reactive component transfer in response to a voltage variation deviation of the grid due to a power transfer between the energy storage unit and the grid.
    Type: Grant
    Filed: December 22, 2015
    Date of Patent: February 25, 2020
    Assignee: Flexgen Power Systems, Inc.
    Inventors: Mengbin Yang, Pasi Taimela, Tony Olivo, Robert William Johnson, Jr., Gopalakrishnan Balakrishnan
  • Patent number: 10523149
    Abstract: A motor control device includes: a PWM count computation unit that computes a PWM count for each of three phases for each current control cycle; a PWM count setting unit that sets the PWM count for each phase in the current control cycle as a PWM count for each PWM cycle in the relevant current control cycle for the corresponding phase; and a common mode noise reduction unit that changes the PWM count in a PWM cycle for at least one phase, of two of the three phases other than one particular phase, such that a current that flows through a stray capacitance because of an output voltage for the one particular phase is canceled out with a current flowing through the stray capacitance because of an output voltage for the at least one of the two other phases in at least one PWM cycle in the current control cycle.
    Type: Grant
    Filed: November 9, 2018
    Date of Patent: December 31, 2019
    Assignee: JTEKT CORPORATION
    Inventor: Hiroshi Sumasu
  • Patent number: 10498142
    Abstract: A device for extinction angle control of a high voltage direct current (HVDC) system, includes: a converter reactive power calculator calculating a reactive power variation amount of a converter included in the HVDC system, depending on firing angle control of the converter; an alternating current (AC) system short circuit level calculator calculating a short circuit level of an AC system by applying the reactive power variation amount to a short circuit level formula of the AC system connected to the HVDC system; an extinction angle variation value calculator calculating an extinction angle variation value of the converter, corresponding to the short circuit level; and an extinction angle controller controlling an extinction angle of the converter, depending on an extinction angle control value reflecting the extinction angle variation value.
    Type: Grant
    Filed: November 24, 2016
    Date of Patent: December 3, 2019
    Assignee: KOREA ELECTRIC POWER CORPORATION
    Inventors: Seong-Doo Lee, Soon-Ho Choi, Chur-Hee Lee
  • Patent number: 10483758
    Abstract: A control apparatus and corresponding control method use per-unit filtering in a plurality of power-sharing controllers, to obtain a power-sharing command signal for respective ones among a plurality of different energy storage units in a hybrid energy storage system. The hybrid energy storage system includes two or more types of energy storage units and the power-sharing command signal for each energy storage unit is obtained by filtering an input signal using a filter having a filter response that is tailored to the energy storage characteristics of the energy storage unit. The input signal reflects load variations on the electrical grid and may be locally generated or provided by a remote node. While the power-sharing control loops used for each energy storage unit advantageously may be the same in terms of architecture and implementation, each loop uses tailored, dedicated filtering and, possibly, individualized values of one or more other control parameters.
    Type: Grant
    Filed: January 8, 2014
    Date of Patent: November 19, 2019
    Assignee: ABB Research Ltd.
    Inventors: Jiaqi Liang, Li Qi
  • Patent number: 10447028
    Abstract: A converter apparatus and methods of operation thereof are disclosed. In an example, a converter unit of a bipole converter apparatus comprising a neutral connection having a breaker switch is disclosed. In the event of a DC fault, the fault condition may be monitored and it is determined whether a breaker switch operation condition is met. The breaker switch is opened when the breaker switch operation condition is met. In one example, the breaker switch operation condition may comprise a current level.
    Type: Grant
    Filed: March 30, 2016
    Date of Patent: October 15, 2019
    Assignee: General Electric Technology GmbH
    Inventors: Robin Gupta, Robert Whitehouse, Carl Barker
  • Patent number: 10283965
    Abstract: A method for incorporating a non-operating station into an operating system in a multi-terminal flexible DC transmission system. The method includes selecting a STATCOM operation mode for the non-operating station; opening a bypass switch at an AC side and connecting a charging resistor to an AC line; closing the AC incoming-line breaker, and pre-charging a converter valve of the non-operating station through the resistor; closing the bypass switch after the pre-charging; selecting a constant-DC voltage control mode for the non-operating station to perform deblocking; controlling the difference between a non-operating station DC voltage value and an operating system direct voltage value to be within an allowable range; closing the pole-connection device at the DC side of a converter of the non-operating station; and switching the non-operating station from the STATCOM operation mode to a DC operation mode, and incorporating the non-operating station into the operating system.
    Type: Grant
    Filed: April 18, 2014
    Date of Patent: May 7, 2019
    Assignees: NR ELECTRIC CO., LTD, NR ENGINEERING CO., LTD
    Inventors: Yunlong Dong, Gang Li, Jie Tian, Nannan Wang, Chao Liu
  • Patent number: 10181799
    Abstract: Disclosed in the present invention is a hybrid back-to-back direct current transmission system. The system includes an LCC converter and a VSC converter in a back-to-back connection, and a first changeover switch, a second changeover switch, a third changeover switch and a fourth changeover switch. The first changeover switch is connected to a first alternating current system and the LCC converter; the second changeover switch is connected to the first alternating current system and the VSC converter; the third changeover switch is connected to a second alternating current system and the VSC converter; and the fourth changeover switch is connected to the second alternating current system and the LCC converter. In forward power delivery, the first changeover switch and the third changeover switch are closed; and in reverse power delivery, the second changeover switch and the fourth changeover switch are closed.
    Type: Grant
    Filed: January 19, 2017
    Date of Patent: January 15, 2019
    Assignees: NR ELECTRIC CO., LTD, NR ENGINEERING CO., LTD
    Inventors: Nannan Wang, Wenqiang Zhao, Yongping Wang
  • Patent number: 10146211
    Abstract: A variable magnetization machine controller including a hysteresis control component configured to receive an ideal magnetization state signal, output an actual magnetization signal based on the ideal magnetization state signal for control of a variable magnetization machine, and modify the actual magnetization state signal in accordance with an error value between the ideal magnetization state signal and the actual magnetization state signal.
    Type: Grant
    Filed: September 12, 2013
    Date of Patent: December 4, 2018
    Assignees: Nissan Motor Co., Ltd., Wisconsin Alumni Research Foundation
    Inventors: Takashi Fukushige, Chen-yen Yu, Robert D. Lorenz
  • Patent number: 10141743
    Abstract: The present invention discloses a Bipolar VSC-HVDC and UPFC Hybrid Topology and its operation method. The first control circuit includes a positive and a negative circuit at the series side, in which the VSC converter can operate in bipolar mode; the second control circuit includes a positive and a negative circuit, in which the VSC converter can operate in bipolar mode; the third control circuit is the same as the second control circuit in terms of structure; the positive electrode and negative electrode of the second control circuit are connected to the DC bus via a DC breaker respectively; the other end of the DC transmission line is connected to the third control circuit via a DC breaker.
    Type: Grant
    Filed: November 30, 2016
    Date of Patent: November 27, 2018
    Assignees: State Grid Jiangsu Electric Power Research Institute, State Grid Corporation of China
    Inventors: Peng Li, Jinjiao Lin, Xiangping Kong, Lei Gao, Haosheng Huang, Xinyue Gong, Yubo Yuan
  • Patent number: 10122180
    Abstract: A bus conditioner for an electrical power system having at least one bus couplable to an electric power generation device driven by a prime mover includes a first energy storage device, a bi-directional power converter including a first converter input electrically connected to the first energy storage device and a converter output for connection to the bus, and a controller operatively coupled to the bi-directional power converter. The controller is configured to maintain a substantially constant load on the power generation device by commanding the power converter to divert excess power into the first energy storage device or use energy from the first storage device to provide power to the bus.
    Type: Grant
    Filed: October 8, 2015
    Date of Patent: November 6, 2018
    Assignee: PARKER-HANNIFIN CORPORATION
    Inventors: Donald Neuhaus, Velimir Nedic
  • Patent number: 10123450
    Abstract: Some embodiments include a high voltage direct current (HVDC) power generator system for information technology (IT) racks. The HVDC power generator system can include a three-phase alternating current (AC) transformer having a primary winding and a plurality of secondary windings. A plurality of three-phase bridge rectifier circuits can be electrically coupled respectively to the plurality of secondary windings. The HVDC power generator system can include output terminals for powering its load. A first string of bridge rectifier circuits can be in series with each other and a first inductor. A second string of bridge rectifier circuits can be in series with each other and a second inductor. The first and second strings can be electrically coupled in parallel to the output terminals.
    Type: Grant
    Filed: May 12, 2016
    Date of Patent: November 6, 2018
    Assignee: Facebook, Inc.
    Inventor: Pierluigi Sarti
  • Patent number: 10116229
    Abstract: The multilevel cascade hexagonal voltage source converter with isolated DC sources has a plurality of polyphase stages, each stage having AC inputs corresponding to a number of phases, and a numerically identical plurality of n outputs, cascaded by connection of the outputs of one stage to the inputs of a next stage. Each stage has plural DC-to-AC converters corresponding to the number of phases, and connected to one of the AC inputs, each having a connection for receiving DC power, and amplifying its AC outputs with the received DC power. The DC-to-AC converters are connected by split inductors, with each split inductor providing an output at a center tap terminal. The inductor half-segments are cross-connected with inductive cross-coupling links inductively connected to the inductor half-segments at opposite sides of the polyphase ring connection. The middle terminals of the n split inductors provide n AC outputs for its respective polyphase stage.
    Type: Grant
    Filed: September 19, 2017
    Date of Patent: October 30, 2018
    Assignee: KING SAUD UNIVERSITY
    Inventors: Abdulrahman Abdullah Ali Alshammaa, Abdullah Mohammed Ali Noman, Khaled Ebraheem Addoweesh, Ayman Abdullah Abdulaziz Alabduljabbar, Abdulrahman Ibrahim Alolah
  • Patent number: 10097002
    Abstract: Embodiments are generally based on employing a power transmission line in a HVDC link to provide auxiliary power to one of the ends of the HVDC link for facilitating a black start thereof when the HVDC link is de-energized, i.e. when at least one of the HVDC converter stations is de-energized and there is no transmission of power between inverter and rectifier HVDC converter stations on each side of the HVDC link. A relatively small amount of power can be conveyed towards one of the HVDC converter stations via the power transmission line so as to provide power to any auxiliary system(s) of the converter station, for example prior to a black start of the converter station being carried out.
    Type: Grant
    Filed: June 30, 2015
    Date of Patent: October 9, 2018
    Assignee: ABB SCHWEIZ AG
    Inventors: Göran Brorsson, Hongbo Jiang, Marcin Szewczyk, Mats Hyttinen, Michal Lazarczyk, Pawel Dawidowski, Radoslaw Jez, Wojciech Piasecki
  • Patent number: 10084387
    Abstract: The present invention discloses an LCC and MMC series-connected HVDC system with DC fault ride-through capacity, comprising rectifier and inverter linked by DC transmission line; Both the positive pole and the negative pole of the rectifier and the inverter consist of line-commutated converter and modular converter in series-connection; the modular converter adopts one MMC or several parallel-connected MMCs. The present invention has the advantage of low cost, low power loss and high reliability of the LCC, as well as flexible control, low harmonics and AC voltage support of the MMC. Further, the present invention is able to deal with DC fault by itself, hence additional DC fault clearing equipment is not needed. As a result, the present invention is suitable for the field of long-distance large-capacity power transmission and has broad development potential.
    Type: Grant
    Filed: April 11, 2016
    Date of Patent: September 25, 2018
    Assignee: ZHEJIANG UNIVERSITY
    Inventors: Zheng Xu, Shijia Wang, Huangqing Xiao
  • Patent number: 10056820
    Abstract: A system includes a current source rectifier which has a plurality of switches configured to receive an input current from an AC voltage source and to receive a plurality of control signals. The switches are configured to produce a rectified output current based on the input current and the control signals. The system also includes a rectifier controller configured to receive a current sense signal indicative of the rectified output current and to generate the control signals based at least in part on the current sense signal, where the control signals cause the current source rectifier to attenuate at least one of a plurality of harmonic frequencies in the rectified output current.
    Type: Grant
    Filed: November 5, 2015
    Date of Patent: August 21, 2018
    Assignee: DRS POWER & CONTROL TECHNOLOGIES, INC.
    Inventors: Robert M. Cuzner, Ashish R. Bendre, William R. Kranz
  • Patent number: 10044193
    Abstract: A voltage at a point of common coupling (PCC) between a photovoltaic (PV) system and a power grid is regulated by a controller having a gain determined according to a gain function that is a function of a time. The gain function is determined based on an error between the voltage measured at the PCC and the reference voltage, and the gain is updated according to the updated gain function and a current instance of time. The controller generates a modulating signal using the updated gain and the voltage at the PCC is regulated according to the modulating signal.
    Type: Grant
    Filed: July 25, 2016
    Date of Patent: August 7, 2018
    Assignee: Mitsubishi Electric Research Laboratories, Inc.
    Inventors: Mouhacine Benosman, Chun Wei
  • Patent number: 9997919
    Abstract: An apparatus for operating a distributed generator in connection with a power system includes an input unit which receives a parameter calculated using power system information and a voltage and a current at a point of common coupling with the distributed generator, with which the distributed generator is connected, a calculation unit which calculates an operating power factor instruction value and an active output instruction value using the parameter and the voltage and current at the point of common coupling with the distributed generator input to the input unit, and a control communication unit which determines and transmits the operating power factor instruction value and the active output instruction value according to the voltage at the point of common coupling with the distributed generator input to the input unit and an admissible voltage upper limit at the point of common coupling with the distributed generator to the distributed generator.
    Type: Grant
    Filed: September 27, 2013
    Date of Patent: June 12, 2018
    Assignee: KOREA ELECTRIC POWER CORPORATION
    Inventors: Seong Soo Cho, Won Wook Jung, Il Keun Song, Sang Ok Kim, Joon Ho Choi
  • Patent number: 9985434
    Abstract: A multi-terminal DC power system includes: a DC network connecting together multiple terminals. Each terminal is represented by one of: a voltage source converter having a capacitor at an interface to the DC network, wherein a difference between a converter-side current and a network-side current charges the capacitor, and a current source converter having an inductor at an interface to the DC network, wherein a difference between a converter-side voltage and a network-side voltage drives current through the inductor. A local controller for each terminal directly controls the converter-side current of each voltage source controller and the converter-side voltage of each current source converter, independent of the terminals, leaving network-side currents and voltages to be determined by the network, resulting in simplified terminal control and avoidance of the need for high-speed communication among all terminals at all times.
    Type: Grant
    Filed: February 25, 2014
    Date of Patent: May 29, 2018
    Assignee: RENSSELAER POLYTECHNIC INSTITUTE
    Inventor: Jian Sun
  • Patent number: 9966777
    Abstract: A modular multilevel converter for hybrid energy storage includes a battery. Three phases are connected in serial to the battery and in parallel to one another, each phase having two arms of sub-modules and buffer inductors. Each of the sub-modules includes a half-bridge and an ultracapacitor. A control module is configured to control the battery output power and ultracapacitor output power independently.
    Type: Grant
    Filed: July 17, 2015
    Date of Patent: May 8, 2018
    Assignee: NEC Corporation
    Inventors: Feng Guo, Ratnesh Sharma
  • Patent number: 9960599
    Abstract: A thyristor controlled LC (TCLC) compensator for compensating dynamic reactive power in a power grid system, with an advantage of mitigating harmonic current injection from solid-state switches during switching on or off is provided. Exemplarily, the TCLC compensator is shunt-connected to the three-phase power grid and comprises an electronic controller, a coupling inductor (Lc), a first branch of circuit with a parallel inductor (LPF) and a solid-state switch, and a second branch of circuit with a parallel capacitor (CPF), wherein the coupling inductor (Lc) is connected in series with a parallel combination of the first and second branch of circuit. The electronic controller for the TCLC compensator is configured in accordance to the generalized instantaneous reactive power theory for improving the response speed instead of using traditional average reactive power concept.
    Type: Grant
    Filed: June 6, 2017
    Date of Patent: May 1, 2018
    Assignee: University of Macau
    Inventors: Lei Wang, Man-Chung Wong, Chi-Seng Lam
  • Patent number: 9937807
    Abstract: The battery charger comprises: two output terminals (BS1, BS2) between which a battery (102) is designed to be connected; two input terminals (BE1, BE2) designed to be connected to an electrical network (110); two inductors (L.A, L.C) respectively connected to the first input terminal (BE1) and to the second input terminal (BE2); two switching arms (BA, BC) for respectively connecting the inductors (LA, LC) selectively to the first output terminal (BS1) and to the second output terminal (BS2); a control device (120) designed for controlling the switching arms (BA, BC) so as to draw from the electrical network (110) a mains current (iR) in phase with the mains voltage (uR). The battery charger further comprises: a smoothing capacitor (C) connected to the second output terminal (BS2); and a connection device (112) for connecting the smoothing capacitor (C) to the second input terminal (BE2). The control device (120) is further designed to control at least the second switching arm (B.sub.
    Type: Grant
    Filed: April 15, 2016
    Date of Patent: April 10, 2018
    Assignee: Valeo Systemes de Controle Moteur
    Inventors: Luis de Sousa, Bruno Condamin, Boris Bouchez, Pierre-Alexandre Chauvenet, Benedicte Silvestre
  • Patent number: 9941772
    Abstract: The present invention provides a marine propulsion system that is suitable for any civilian and military marine vessels and which offers operational flexibility. The marine propulsion system includes a pair of ac busbars, each in parallel connection with a power converter. The respective power converters each connected in parallel to a propulsion motor.
    Type: Grant
    Filed: October 14, 2010
    Date of Patent: April 10, 2018
    Assignee: GE Energy Power Conversion Technology LTD.
    Inventor: Eric Anthony Lewis
  • Patent number: 9929667
    Abstract: Provided herein is a fusion energy extraction circuit (FEEC) device having a grid-tied bidirectional converter and a resonant converter. The resonant converter can include an inverse cyclotron converter with two or more or quadruple plates and a plurality of circuit switches. The bidirectional converter can include a three-phase grid-tied converter. The FEEC device is capable of decelerating plasma particle beams, thereby extracting the energy from the deceleration, converting the extracted energy to electric energy, and sending the electric energy to a power grid.
    Type: Grant
    Filed: April 13, 2016
    Date of Patent: March 27, 2018
    Assignee: THE REGENTS OF THE UNIVERSITY OF THE CALIFORNIA
    Inventors: Keyue Smedley, Frank J. Wessel, Mingying Gu, In Wha Jeong
  • Patent number: 9876393
    Abstract: The present invention discloses a direct current (DC) voltage control method. The present invention further discloses an apparatus for implementing the method. With the present invention, DC voltage oscillation of a system, which is caused when a DC voltage primary control station stops running, may be reduced.
    Type: Grant
    Filed: September 25, 2014
    Date of Patent: January 23, 2018
    Assignees: NR ELECTRIC CO., LTD, NR ENGINEERING CO., LTD
    Inventors: Yunlong Dong, Jie Tian, Haiying Li, Dongming Cao
  • Patent number: 9870593
    Abstract: A system, method and controller for managing and controlling a micro-grid network. The system includes a plurality of energy resources including at least one dispatchable energy resource and at least one intermittent energy resource, wherein the at least one of the energy resources is an energy storage element and at least one of the intermittent energy resources is responsive to environmental conditions to generate power, a controller configured to record operational constraints of the energy resources, obtain an environmental condition prediction and generate a component control signal based on the environmental condition prediction and the operational constraints corresponding to the energy resources. The controller is further configured to receive a network disturbance signal and generate a dynamic control signal based on such disturbances.
    Type: Grant
    Filed: December 5, 2012
    Date of Patent: January 16, 2018
    Assignee: HATCH LTD.
    Inventors: Mohammad Sedighy, Mohamed Zakaria Kamh, Amgad El-Deib, Reza Iravani, Abdelrahman Abbas Hagar
  • Patent number: 9825554
    Abstract: A voltage source converter comprises first and second DC terminals for connection to a DC network, and at least one limb connected between the first and second DC terminals. The or each limb includes: a phase element including two parallel-connected sets of series-connected switching elements connected in an H-bridge to define first and second diagonal switching pairs, a respective junction between each set of series-connected switching elements defining an AC terminal for connection to an AC network; and a sub-converter configured to be controllable to act as a voltage waveform synthesizer. The voltage source converter further includes a controller to operate the sub-converter to selectively synthesize a driving commutation voltage to modify a DC side current at a DC side of the H-bridge to minimize any differences in magnitude and direction between the DC side current and an AC side current at an AC side of the H-bridge.
    Type: Grant
    Filed: March 4, 2015
    Date of Patent: November 21, 2017
    Assignee: GENERAL ELECTRIC TECHNOLOGY GMBH
    Inventors: David Reginald Trainer, Omar Fadhel Jasim, Jonathan Charles Clare
  • Patent number: 9819187
    Abstract: A power supply device for HVDC controller is provided. The power supply device comprises: a first High Voltage Direct Current (HVDC) converter unit connected to an active power grid; a second HVDC converter unit connected to a passive power grid, the second HVDC converter unit being capable of receiving first DC power from the first HVDC converter unit by being connected to the first HVDC converter unit via a Direct Current (DC) transmission line; and an HVDC controller, arranged in the second HVDC converter unit, for receiving the first DC power, applied from the first HVDC converter unit to the second HVDC converter unit, by being connected to the DC transmission line that connects the first HVDC converter unit with the second HVDC converter unit.
    Type: Grant
    Filed: December 24, 2014
    Date of Patent: November 14, 2017
    Assignee: HYOSUNG CORPORATION
    Inventors: Jung-Soo Park, Hong-Ju Jung, June-Sung Kim
  • Patent number: 9780658
    Abstract: An intermediate voltage circuit current converter having two current converter sections arranged in series on the direct voltage side is disclosed. The current converter section has a capacitor connected in parallel with two bridge modules that are connected in series with each other. The output of the current converter section is located on the series connection between the two bridge modules and the outputs of the two current converter sections are connected to a further bridge module. Each bridge modules comprises a series connection of two power semiconductor units. The intermediate potentials on the connection between the two power semiconductor units in each of the bridge modules are electrically connected to one another by a further capacitor, and the intermediate potential of the further bridge module provides the phase connection of the intermediate voltage circuit current converter for a given phase of the intermediate voltage circuit current converter.
    Type: Grant
    Filed: September 29, 2015
    Date of Patent: October 3, 2017
    Assignee: SIEMENS AKTIENGESELLSCHAFT
    Inventors: Hans-Günter Eckel, Sidney Gierschner
  • Patent number: 9735697
    Abstract: A converter performs full-wave rectification on a single-phase voltage, thus outputting a rectified voltage across DC power supply lines. An inverter receives the rectified voltage and then supplies a three-phase AC current to an inductive load. Between the DC power supply lines is connected a charge and discharge circuit. The charge and discharge circuit includes a buffer circuit and a boost circuit. The buffer circuit includes a series connection between a capacitor and a switch. The boost circuit, which may be configured by a boost chopper, includes a switch, a reactor and a diode. The charge and discharge circuit provides and receives part of pulsations of the power input to the converter between the DC power supply lines.
    Type: Grant
    Filed: August 27, 2014
    Date of Patent: August 15, 2017
    Assignee: DAIKIN INDUSTRIES, LTD.
    Inventor: Kenichi Sakakibara
  • Patent number: 9735580
    Abstract: 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 W1 and W2 transmitting the DC power obtained from the rectifier through conversion to the inverter; 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 controlling the operations of the rectifier and the inverter based on the first active power measured and the second active power measured, wherein the first control unit senses oscillation generated in the HVDC transmission system and generates a control signal for damping the sensed oscillation to control one or more of the rectifier and the inverter.
    Type: Grant
    Filed: April 24, 2015
    Date of Patent: August 15, 2017
    Assignee: LSIS CO., LTD.
    Inventors: Gum Tae Son, Ho Hwan Park
  • Patent number: 9627979
    Abstract: In a method of operating a dual mode DC-DC converter having first and second bridge converters connected via a transformer, a capacitor in series with each winding of the transformer, and an inductance, wherein each bridge converter includes a number of switches operating under the control of a controller, in a first mode of operation, the switching of the number of switches is controlled in a manner to transfer DC electrical power from the first bridge converter to the second bridge converter, or vice versa. In a second mode of operation, one switch of each bridge converter is maintained in a closed state and one switch of each bridge converter is maintained in an open state while the switching of the other of the number of switches of the first and second bridge converters is controlled in a manner to transfer DC electrical power from the first bridge converter to the second bridge converter, or vice versa.
    Type: Grant
    Filed: October 3, 2014
    Date of Patent: April 18, 2017
    Assignee: Bombardier Transportation GmbH
    Inventors: Alireza Safaee, Konrad Woronowicz
  • Patent number: 9614455
    Abstract: 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.
    Type: Grant
    Filed: April 24, 2015
    Date of Patent: April 4, 2017
    Assignee: LSIS CO., LTD.
    Inventors: Gum Tae Son, Ho Hwan Park
  • Patent number: 9590485
    Abstract: A resonance suppression device, in which power loss and apparatus capacitance are reduced by outputting a compensating current only while a voltage resonance is being generated, and which suppresses resonance generated by connection of a power apparatus to a power system. In one embodiment, the device includes a capacitance change detector that detects a change of an electrostatic capacitance (impedance) connected to the power system. When the resonance detector detects the resonance, a current command value generator generates the current command value on the basis of harmonic components included in a current supplied from the power apparatus to the power system. When the impedance change detector detects a change of the impedance, the current command value generator generates the current command value so as to reduce the compensating current.
    Type: Grant
    Filed: September 10, 2015
    Date of Patent: March 7, 2017
    Assignee: FUJI ELECTRIC CO., LTD.
    Inventors: Toru Jintsugawa, Kenya Murakami
  • Patent number: 9584036
    Abstract: We describe a photovoltaic power conditioning unit comprising: both dc and ac power inputs; a dc link; at least one dc-to-dc converter coupled between dc input and dc link; and a dc-to-ac converter coupled between dc link and ac output. The dc-to-dc converter comprises: a transformer having input and output windings; an input dc-to-ac converter coupled between dc input and input winding; and an ac-to-dc converter coupled between output winding the dc link. The output winding has a winding tap between the first and second portions. The ac-to-dc converter comprises: first and second rectifiers, each connected to a respective first and second portion of the output winding, to the dc link and winding tap; and a series inductor connected to the winding tap. Rectifiers are connected to the winding tap of the output winding via the series inductor wherein the series inductor is shared between the first and second rectifiers.
    Type: Grant
    Filed: November 10, 2014
    Date of Patent: February 28, 2017
    Assignee: SolarCity Corporation
    Inventor: Paul Garrity
  • Patent number: 9553526
    Abstract: In a converter for converting energy from a generator to a power network, wherein the converter comprises multiple power modules, wherein each power module includes at least two power cells and a transformer for connecting the power cells to the power network, wherein each power cell includes a phase input, a phase output, a transformer output connected to the transformer, a rectifier circuit and an inverter, the transformer (T) of a power module (4.1, . . . , 4.n) includes one generator-side winding (10) for each of the power cells (5) and exactly one common grid-side winding for balancing an energy flow through the power cells (5) of a power module (4.1, . . . , 4.n).
    Type: Grant
    Filed: January 23, 2014
    Date of Patent: January 24, 2017
    Assignee: DET INTERNATIONAL HOLDING LIMITED
    Inventors: Kilian Noetzold, Michael Bragard, Karsten Fink, Richard Griessel, Ralf Wegener
  • Patent number: 9515575
    Abstract: A controller of a power conversion apparatus according to an embodiment causes a chopper and an inverter to generate an alternating-current (AC) voltage including first and second parts of an AC voltage waveform and causes the inverter to output the AC voltage. The chopper generates the first part having an absolute value higher than a voltage of a DC power supply, and the inverter generates the second part having an absolute value lower than the voltage of the DC power supply. The controller is configured to alternately turn on the first and second switching elements in a period during which the controller controls the chopper to generate the first part of the AC voltage waveform.
    Type: Grant
    Filed: April 29, 2015
    Date of Patent: December 6, 2016
    Assignee: KABUSHIKI KAISHA YASKAWA DENKI
    Inventors: Tetsumi Narita, Masato Higuchi, Yasuhiko Kawanami, Hidenori Hara, Takamitsu Katsuki
  • Patent number: 9502991
    Abstract: The present invention discloses a hybrid converter and a wind power generating system, the hybrid converter including a voltage source converter, a line commutated converter and a line commutated converter, a positive DC terminal of the voltage source converter is connected to a negative DC terminal of the line commutated converter, a positive DC terminal of the line commutated converter is connected to a positive DC transmission line, a negative DC terminal of the voltage source converter is connected to a positive DC terminal of the line commutated converter, and a negative DC terminal of the line commutated converter is connected to a negative DC transmission line. The present invention features a self-commutating capability, can be directly connected to a wind farm to convert wind power to DC power, and is able to improve rated voltage and rated power of the hybrid converter, technology of each component thereof is mature, and system reliability thereof is high.
    Type: Grant
    Filed: February 25, 2014
    Date of Patent: November 22, 2016
    Assignee: HUAZHONG UNIVERSITY OF SCIENCE AND TECHNOLOGY
    Inventors: Weixing Lin, Jinyu Wen, Shaorong Wang, Shijie Cheng
  • Patent number: 9502903
    Abstract: Example energy management systems and methods are described. In one implementation, a system includes an inverter and a combiner module coupled to the inverter. The combiner module receives DC signals from multiple DC sources and delivers a DC output signal. A control module manages a voltage and a current associated with the DC output signal delivered by the combiner module.
    Type: Grant
    Filed: January 13, 2014
    Date of Patent: November 22, 2016
    Assignee: McCalmont Corporation
    Inventors: Aaron William McCalmont, David Thompson McCalmont
  • Patent number: 9500696
    Abstract: Provided is a synthetic test circuit for synthetic-testing a thyristor valve in high voltage direct current (HVDC). A resonant circuit applies forward DC current, a reverse DC voltage, and a forward DC voltage to synthetic-test the thyristor valve. A current generation unit generates DC current that is above a reference current value to supply the generated DC current into the resonant circuit. A voltage generates unit generating a DC voltage that is above a reference voltage value to supply the generated DC voltage into the resonant circuit. The resonant circuit includes a charging auxiliary valve for charging a gate driver of the thyristor valve.
    Type: Grant
    Filed: July 3, 2014
    Date of Patent: November 22, 2016
    Assignee: LSIS CO., LTD.
    Inventors: Jun Bum Kwon, Teag Sun Jung, Seung Taek Baek, Wook Hwa Lee, Yong Ho Chung
  • Patent number: 9490693
    Abstract: 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.
    Type: Grant
    Filed: April 13, 2015
    Date of Patent: November 8, 2016
    Assignee: Alstom Technology Ltd.
    Inventors: David Trainer, Colin Charnock Davidson, Nnamdi Okaeme
  • Patent number: 9379633
    Abstract: A method to control a voltage source converter (CON1; CON2) in a HVDC system comprises the step of controlling a frequency and a voltage amplitude of an AC voltage (UV1; UV2) generated by the voltage source converter (CON1; CON2) independently of the conditions in an AC network (N1; N2) connected to the voltage source converter (CON1; CON2). This method is performed by a control unit of a HVDC system. In a special embodiment, the method forms the basis of a method to black start an AC network, where the AC network comprises transmission lines and is connected to at least two AC power stations, where one of the at least two AC power stations is connected via a HVDC system to the AC network.
    Type: Grant
    Filed: July 22, 2013
    Date of Patent: June 28, 2016
    Assignee: ABB TECHNOLOGY LTD.
    Inventor: Ying Jiang-Häfner
  • Patent number: 9331481
    Abstract: A power transmission system is provided. The power transmission system includes at least one power substation for receiving power from a power source, and a Direct Current (DC) cable for transferring the power from the power source to the power substation. The DC cable includes a plurality of segments individually or in combination forming a path to route the power to the power substation. The system further includes at least one segment switch unit electrically coupled to each segment. At least one of the segment switch units includes a shorting switch element for providing a short circuit path to prevent the power from the power source to be routed to a respective segment in response to a shorting command, and a disconnect switch element for disconnecting the respective segment in response to a disconnect command.
    Type: Grant
    Filed: August 31, 2012
    Date of Patent: May 3, 2016
    Assignee: General Electric Company
    Inventors: Piniwan Thiwanka Bandara Wijekoon, Christof Martin Sihler, Simon Herbert Schramm
  • Patent number: 9325251
    Abstract: A system for delivering power to an offshore load is disclosed. The system may include an on-land source of three-phase power, an on-land AC-to-DC power conversion module, a DC transmission line, and an offshore DC-to-AC power inverter. The on-land AC-to-DC power conversion module may be configured to convert the three-phase power to DC power. The DC transmission line may have a source end and a load end, where the source end is configured to receive DC power from the on-land AC-to-DC power conversion module. The offshore DC-to-AC power inverter may be configured to receive DC power from the DC transmission line, convert the DC power to three-phase AC power, and deliver the three-phase AC power to an offshore load.
    Type: Grant
    Filed: August 29, 2013
    Date of Patent: April 26, 2016
    Assignee: SIEMENS AKTIENGESELLSCHAFT
    Inventors: John Channing Bousfield, III, Mukul Rastogi, Elena V. Koneva
  • Patent number: 9300132
    Abstract: A power generation system includes at least one generator having at least two sets of stator windings, an active rectifier comprising power cell based modular converters associated with each set of generator windings. Each set of windings is connected to an AC voltage side of the associated active rectifier, with each active rectifier having a positive DC voltage output and a negative DC voltage output. The DC voltage outputs of active rectifiers are connected to each other in series. A medium voltage DC (MVDC) collection network comprises positive pole cables and negative pole cables, wherein each positive pole cable is connected to the positive DC voltage output of a first active rectifier and each negative pole cable is connected to the negative DC voltage output of a last active rectifier. A substation receives the negative and positive pole cables of the MVDC collection network for further transformation and transmission.
    Type: Grant
    Filed: February 2, 2012
    Date of Patent: March 29, 2016
    Assignee: ABB RESEARCH LTD
    Inventors: Jiuping Pan, Hongrae Kim, Jun Li, Jing Xu, Jyoti Sastry, Waqas Arshad
  • Patent number: 9077201
    Abstract: An uninterruptible power supply device including a rectifier circuit rectifying output power of an inverter. At a first startup of the inverter, output power of the rectifier circuit is supplied to an electric double-layer capacitor. At second and subsequent startups of the inverter, output power of one of a converter and the rectifier circuit is selectively supplied to the electric double-layer capacitor. Therefore, by controlling the inverter, the electric double-layer capacitor can be precharged easily with a simple configuration.
    Type: Grant
    Filed: May 29, 2009
    Date of Patent: July 7, 2015
    Assignee: TOSHIBA MITSUBISHI-ELECTRIC INDUSTRIAL SYSTEMS CORPORATION
    Inventors: Kazumasa Matsuoka, Katsumi Ikeda
  • Patent number: 9065299
    Abstract: 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.
    Type: Grant
    Filed: June 18, 2010
    Date of Patent: June 23, 2015
    Assignee: Alstom Technology LTD
    Inventors: David Trainer, Colin Charnock Davidson, Nnamdi Okaeme
  • Patent number: 9048694
    Abstract: Connection schemes for offshore power generation with an internal collection grid include a power generation system which includes a plurality of generator-rectifier subsystems. The scheme further includes a medium voltage DC (MVDC) collection network with positive pole cables and negative pole cables connected to the DC outputs of the generator-rectifier subsystems. At least one offshore substation includes a positive bus bar and a negative bus bar correspondingly connected to the positive pole cables and negative pole cables of the MVDC collection network and a plurality of main DC-DC converters. Each main DC-DC converter includes multiple modules connected to the MVDC bus bars and each module has a positive and a negative output such that the modules' outputs are serially connected to one another. The schemes may also include a high voltage DC (HVDC) transmission system connected to the modules' outputs and at least one DC/AC converter at an onshore substation.
    Type: Grant
    Filed: February 1, 2012
    Date of Patent: June 2, 2015
    Assignee: ABB RESEARCH LTD
    Inventors: Jiuping Pan, Li Qi, Jun Li, Muhamad Reza, Kailash Srivastava
  • Publication number: 20150145252
    Abstract: The present invention discloses a hybrid converter and a wind power generating system, the hybrid converter comprising a voltage source converter, a line commutated converter and a line commutated converter, a positive DC terminal of the voltage source converter is connected to a negative DC terminal of the line commutated converter, a positive DC terminal of the line commutated converter is connected to a positive DC transmission line, a negative DC terminal of the voltage source converter is connected to a positive DC terminal of the line commutated converter, and a negative DC terminal of the line commutated converter is connected to a negative DC transmission line. The present invention features a self-commutating capability, can be directly connected to a wind farm to convert wind power to DC power, and is able to improve rated voltage and rated power of the hybrid converter, technology of each component thereof is mature, and system reliability thereof is high.
    Type: Application
    Filed: February 25, 2014
    Publication date: May 28, 2015
    Inventors: Weixing Lin, Jinyu Wen, Shaorong Wang, Shijie Cheng
  • Patent number: 9042129
    Abstract: An integrated power quality control system includes a transformer with a primary winding, a secondary winding and a compensation winding wound on a magnetic core. A power electronic converter in the system provides a reference voltage to the compensation winding for injecting a series voltage in the secondary winding of the transformer. A controller is utilized to generate a reference control voltage for the power electronic converter based on a power quality control requirement.
    Type: Grant
    Filed: November 15, 2012
    Date of Patent: May 26, 2015
    Assignee: General Electric Company
    Inventors: Pinwan Thiwanka Bandara Wijekoon, Ara Panosyan, Manoj Ramprasad Shah