Patents by Inventor Gerardo Escobar

Gerardo Escobar has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 9344005
    Abstract: Exemplary embodiments are directed to methods and systems for producing a three-phase current to a three-phase output. Switching converters are used to generate a positive current, a negative current, and an intermediate current. The system is configured such that the produced positive current follows a path of a highest phase of a sinusoidal three-phase signal at a given time, the produced negative current follows a path of a lowest phase of the three-phase signal at the given time, and the produced intermediate current follows a path of a phase of the three-phase signal between the highest and the lowest phase at the given time. The produced currents are switched to each phase conductor of the three-phase output in sequence so that phase currents of the three-phase current are formed in the output conductors.
    Type: Grant
    Filed: February 21, 2014
    Date of Patent: May 17, 2016
    Assignee: ABB RESEARCH LTD.
    Inventors: Ngai-Man Ho, Gerardo Escobar, Francisco Canales
  • Patent number: 9331563
    Abstract: Exemplary embodiments are directed to an snubber circuit and a power converter having an active circuit. The snubber circuit includes a series connection of a first diode and a first inductor connected between a first interfacing point and a first connection point, a second diode connected between a second connection point and a second interfacing point, a series connection of a third diode and a second inductor between a third interfacing point and the second connection point, a switching device connected between the first connection point and the third interfacing point, and a first capacitor connected between the first connection point and the second connection point. The first, the second, and the third diode are forward-biased along a path between the first interfacing point and the second interfacing point and through the third interfacing point.
    Type: Grant
    Filed: April 1, 2014
    Date of Patent: May 3, 2016
    Assignee: ABB RESEARCH LTD
    Inventors: Tin-Ho Li, Ngai-Man Ho, Gerardo Escobar, Jonathan Bradshaw
  • Patent number: 9331486
    Abstract: An exemplary method and apparatus for detecting islanding conditions of a distributed grid are disclosed, wherein transfer of power through a power electrical unit is controlled on the basis of a control reference. The apparatus includes a first stage and a second stage performing a respective portion of the method. The first stage injects a reactive component to the control reference, and, for at least one electrical quantity of the grid, determines a change in the quantity induced by the injected component, and determines, on the basis of the change in the electrical quantity, whether to move to the second stage of the method.
    Type: Grant
    Filed: November 5, 2012
    Date of Patent: May 3, 2016
    Assignee: ABB RESEARCH LTD
    Inventors: Gerardo Escobar, Sami Pettersson, Leonardo-Augusto Serpa, Ngai-Man Ho, Antonio Coccia, Alexandre Oudalov, Adrian Timbus
  • Patent number: 9030854
    Abstract: An exemplary method and an apparatus implementing the method for an arrangement having a three-phase, multi-level inverter, an output LCL-filter connecting the inverter to a grid, and a virtual-ground connection between the LCL-filter and the neutral point of the DC-link. The method includes determining a zero-sequence component of an LCL-filter inverter-side current, calculating a zero-sequence damping and balancing voltage term based on the LCL-filter inverter-side current zero-sequence component and voltages over the two halves of the DC-link, and adding the zero-sequence damping and voltage balancing term to the output voltage reference.
    Type: Grant
    Filed: June 7, 2013
    Date of Patent: May 12, 2015
    Assignee: ABB Research Ltd
    Inventors: Gerardo Escobar, Sami Pettersson, Ngai-Man Ho
  • Patent number: 8929108
    Abstract: A method and an apparatus for controlling a grid-connected converter which includes a boost converter, a buck converter, and a current source inverter having an output CL filter. An input of the buck converter input is connected to an output of the boost converter, and an input of the current source inverter is connected to an output of the buck converter. The method includes controlling a boost converter input voltage, controlling a boost converter output voltage through control of a buck converter output voltage, and controlling the current source inverter to produce an AC current from the buck converter output voltage. The apparatus implements the method.
    Type: Grant
    Filed: February 21, 2013
    Date of Patent: January 6, 2015
    Assignee: ABB Research Ltd
    Inventors: Gerardo Escobar, Ngai-Man Ho, Sami Pettersson
  • Publication number: 20140313627
    Abstract: Exemplary embodiments are directed to an snubber circuit and a power converter having an active circuit. The snubber circuit includes a series connection of a first diode and a first inductor connected between a first interfacing point and a first connection point, a second diode connected between a second connection point and a second interfacing point, a series connection of a third diode and a second inductor between a third interfacing point and the second connection point, a switching device connected between the first connection point and the third interfacing point, and a first capacitor connected between the first connection point and the second connection point. The first, the second, and the third diode are forward-biased along a path between the first interfacing point and the second interfacing point and through the third interfacing point.
    Type: Application
    Filed: April 1, 2014
    Publication date: October 23, 2014
    Applicant: ABB Research Ltd
    Inventors: Tin-Ho LI, Ngai-Man Ho, Gerardo Escobar, Jonathan Bradshaw
  • Publication number: 20140241016
    Abstract: Exemplary embodiments are directed to methods and systems for producing a three-phase current to a three-phase output. Switching converters are used to generate a positive current, a negative current, and an intermediate current. The system is configured such that the produced positive current follows a path of a highest phase of a sinusoidal three-phase signal at a given time, the produced negative current follows a path of a lowest phase of the three-phase signal at the given time, and the produced intermediate current follows a path of a phase of the three-phase signal between the highest and the lowest phase at the given time. The produced currents are switched to each phase conductor of the three-phase output in sequence so that phase currents of the three-phase current are formed in the output conductors.
    Type: Application
    Filed: February 21, 2014
    Publication date: August 28, 2014
    Applicant: ABB Research Ltd
    Inventors: Ngai-Man HO, Gerardo ESCOBAR, Francisco CANALES
  • Patent number: 8751177
    Abstract: An exemplary method and arrangement for estimating the frequency and the positive sequence of a fundamental component of a measured three-phase voltage are disclosed (???).
    Type: Grant
    Filed: March 30, 2011
    Date of Patent: June 10, 2014
    Assignee: ABB Research Ltd.
    Inventors: Gerardo Escobar, Antonio Coccia, Leonardo-Augusto Serpa, Sami Pettersson, Yales De-Novaes
  • Patent number: 8704499
    Abstract: A method and apparatus of tracking the maximum power point of a photovoltaic module. The method includes measuring an output voltage of the photovoltaic module, determining an output voltage of the inverter connected to the photovoltaic module, and measuring output current of the inverter connected to the photovoltaic module. A variable relating to energy of the capacitor is defined using the measured PV module output voltage, and a second harmonic component is extracted from the defined variable. A second harmonic component of the module output power is estimated using the defined variable, measured output current of the inverter, and the determined output voltage of the inverter. The estimated and extracted second harmonic components are multiplied, and a DC component is extracted from the product. A control signal for controlling the inverter connected to the photovoltaic module is formed by using the extracted DC component in a PI algorithm.
    Type: Grant
    Filed: September 14, 2011
    Date of Patent: April 22, 2014
    Assignee: ABB Research Ltd.
    Inventors: Gerardo Escobar, Tuomas Pulli, Matti Karppanen
  • Publication number: 20140043014
    Abstract: A phase-locked loop and method for estimating a phase angle of a three-phase reference signal is disclosed, which includes an adaptive quadrature signal generator configured to calculate an estimated first state and an estimated second state of a model of an unbalanced three-phase system at a fundamental frequency of the reference signal on a basis of the reference signal and an estimated fundamental frequency; a reference frame transformation block configured to calculate a direct component and a quadrature component in a rotating reference frame synchronous with an estimated phase angle on a basis of the fundamental positive sequence component and the estimated phase angle, and configured to determine an estimate of an amplitude of the fundamental positive sequence component on the basis of the direct component; and an estimator configured to determine estimates of the estimated fundamental frequency and the estimated phase angle on the basis of the quadrature component.
    Type: Application
    Filed: August 12, 2013
    Publication date: February 13, 2014
    Applicant: ABB Technology AG
    Inventors: Ngai-Man HO, Gerardo ESCOBAR, Sami PETTERSSON
  • Publication number: 20130329471
    Abstract: An exemplary method and an apparatus implementing the method for an arrangement having a three-phase, multi-level inverter, an output LCL-filter connecting the inverter to a grid, and a virtual-ground connection between the LCL-filter and the neutral point of the DC-link. The method includes determining a zero-sequence component of an LCL-filter inverter-side current, calculating a zero-sequence damping and balancing voltage term based on the LCL-filter inverter-side current zero-sequence component and voltages over the two halves of the DC-link, and adding the zero-sequence damping and voltage balancing term to the output voltage reference.
    Type: Application
    Filed: June 7, 2013
    Publication date: December 12, 2013
    Inventors: Gerardo ESCOBAR, Sami PETTERSSON, Ngai-Man HO
  • Patent number: 8553434
    Abstract: A method of controlling the grid-side current of a single-phase grid-connected converter having an LCL filter connected between the output of the converter and the grid includes measuring a grid voltage and at least one signal in a group of signals consisting of a grid-side current, a converter-side current and a capacitor voltage, estimating the fundamental component of the grid voltage, forming a grid-side current reference, a converter-side current reference and a capacitor voltage reference for the grid-side current of the LCL filter, forming estimates for the non-measured signals in the group of signals, forming a grid-side current difference term, a converter-side current difference term and a capacitor voltage difference term, and controlling the output voltage of the converter based on the grid voltage, a formed injection term and a formed estimate of the harmonic distortion term to produce a grid side current corresponding to the current reference.
    Type: Grant
    Filed: February 18, 2011
    Date of Patent: October 8, 2013
    Assignee: ABB Research Ltd
    Inventors: Antonio Coccia, Gerardo Escobar, Leonardo-Augusto Serpa, Mikko Paakkinen, Sami Pettersson
  • Publication number: 20130229839
    Abstract: A method and an apparatus for controlling a grid-connected converter which includes a boost converter, a buck converter, and a current source inverter having an output CL filter. An input of the buck converter input is connected to an output of the boost converter, and an input of the current source inverter is connected to an output of the buck converter. The method includes controlling a boost converter input voltage, controlling a boost converter output voltage through control of a buck converter output voltage, and controlling the current source inverter to produce an AC current from the buck converter output voltage. The apparatus implements the method.
    Type: Application
    Filed: February 21, 2013
    Publication date: September 5, 2013
    Applicant: ABB Research Ltd.
    Inventors: Gerardo ESCOBAR, Ngai-Man Ho, Sami Pettersson
  • Publication number: 20120242152
    Abstract: An exemplary method is disclosed for searching a global maximum power point in an arrangement comprising a series connection of photovoltaic power sources. The method can include determining a value of a reference by adding an increment to a previous value of the reference, wherein the value of the increment is determined on the basis of the power produced by the power sources.
    Type: Application
    Filed: March 22, 2012
    Publication date: September 27, 2012
    Applicant: ABB Research Ltd
    Inventors: Gerardo ESCOBAR, Ngai-Man Ho, Sami Pettersson, Leonardo-Augusto Serpa, Antonio Coccia
  • Publication number: 20120239215
    Abstract: A method and apparatus are provided for detecting islanding conditions for distributed generators connected to a grid. The method includes estimating a grid impedance, and inducing, on the basis of the estimated grid impedance, a variation on a value of a first electrical quantity of the grid. The method also includes monitoring a grid response to the variations, and determining islanding conditions on the basis of the monitored response.
    Type: Application
    Filed: March 14, 2012
    Publication date: September 20, 2012
    Applicant: ABB RESEARCH LTD
    Inventors: Adrian Timbus, Alexandre Oudalov, Gerardo Escobar, Leonardo-Augusto Serpa
  • Publication number: 20120069602
    Abstract: A method and apparatus of tracking the maximum power point of a photovoltaic module. The method includes measuring an output voltage of the photovoltaic module, determining an output voltage of the inverter connected to the photovoltaic module, and measuring output current of the inverter connected to the photovoltaic module. A variable relating to energy of the capacitor is defined using the measured PV module output voltage, and a second harmonic component is extracted from the defined variable. A second harmonic component of the module output power is estimated using the defined variable, measured output current of the inverter, and the determined output voltage of the inverter. The estimated and extracted second harmonic components are multiplied, and a DC component is extracted from the product. A control signal for controlling the inverter connected to the photovoltaic module is formed by using the extracted DC component in a PI algorithm.
    Type: Application
    Filed: September 14, 2011
    Publication date: March 22, 2012
    Applicant: ABB RESEARCH LTD
    Inventors: Gerardo Escobar, Tuomas Pulli, Matti Karppanen
  • Publication number: 20110241652
    Abstract: An exemplary method and arrangement for estimating the frequency and the positive sequence of a fundamental component of a measured three-phase voltage are disclosed (???).
    Type: Application
    Filed: March 30, 2011
    Publication date: October 6, 2011
    Applicant: ABB Research Ltd
    Inventors: Gerardo Escobar, Antonio Coccia, Leonardo-Augusto Serpa, Sami Pettersson, Yales De-Novaes
  • Publication number: 20110221420
    Abstract: A method of controlling the grid-side current of a single-phase grid-connected converter having an LCL filter connected between the output of the converter and the grid. The method includes measuring a grid voltage (vS) and at least one signal in a group of signals consisting of a grid-side current (i0), a converter-side current (i1) and a capacitor voltage (vC0).
    Type: Application
    Filed: February 18, 2011
    Publication date: September 15, 2011
    Applicant: ABB Research Ltd.
    Inventors: Antonio COCCIA, Gerardo Escobar, Leonardo-Augusto Serpa, Mikko Paakkinen, Sami Pettersson
  • Publication number: 20110103118
    Abstract: A non-isolated DC-DC converter assembly includes a boost converter and a ?uk converter connected together in a specific way. The non-isolated DC-DC converter assembly allows for grounding of a source and load at the same time, and provides a complete adjustability of the output voltage of the non-isolated DC-DC converter.
    Type: Application
    Filed: November 2, 2010
    Publication date: May 5, 2011
    Applicant: ABB Research Ltd.
    Inventors: Leonardo-Augusto SERPA, Mikko Paakkinen, Francisco Canales, Gerardo Escobar, Antonio Coccia
  • Patent number: 7904495
    Abstract: A repetitive controller scheme with negative feedback and feedforward introduces infinitely many poles on the imaginary axis located at the resonant peaks. The feedforward introduces zeros, which produce notches located in between two consecutive resonant peaks. The latter has the advantage of making the controllers more selective, in the sense that the original overlapping (appearing at the valleys) or interaction between consecutive resonant peaks is removed by the notches. This would allow, in principle, peaks of higher gains and slightly wider bandwidth, avoiding, at the same time, the excitation of harmonics located in between two consecutive peaks. A negative feedback compensator with feedforward is especially useful when only the compensation of odd harmonics is required, but not the even harmonics, like in many power electronic systems. In contrast, the positive feedback controller would try to reinject, and indeed amplify, any small noise, which has components on the even frequencies.
    Type: Grant
    Filed: September 22, 2005
    Date of Patent: March 8, 2011
    Assignee: Instituto Potosino De Investigacion Cientifica y Tecnologica
    Inventors: Jesus Leyva Ramos, Gerardo Escobar