Patents by Inventor Ngai Man Ho

Ngai Man Ho 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).

  • 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
  • Patent number: 8488351
    Abstract: An exemplary non-isolated DC-DC converter for a solar power plant, can be adapted to connect to a full-bridge inverter. The converter includes positive and negative input terminals, and positive and negative output terminals. A plurality of switches, diodes, inductors and capacitors are connected in a circuit configuration to the input and output terminals. A control means is connected to the circuit for controlling the switching of a first, second, and third switch between an open and closed state.
    Type: Grant
    Filed: March 17, 2011
    Date of Patent: July 16, 2013
    Assignee: ABB Research Ltd.
    Inventors: Leonardo-Augusto Serpa, Francisco Canales, Ngai-Man Ho, Antonio Coccia
  • 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: 20110228578
    Abstract: An exemplary non-isolated DC-DC converter for a solar power plant, can be adapted to connect to a full-bridge inverter. The converter includes positive and negative input terminals, and positive and negative output terminals. A plurality of switches, diodes, inductors and capacitors are connected in a circuit configuration to the input and output terminals. A control means is connected to the circuit for controlling the switching of a first, second, and third switch between an open and closed state.
    Type: Application
    Filed: March 17, 2011
    Publication date: September 22, 2011
    Applicant: ABB Research Ltd.
    Inventors: Leonardo-Augusto Serpa, Francisco Canales, Ngai-Man Ho, Antonio Coccia
  • Patent number: 7411359
    Abstract: Dimming of an electrical lamp of the type driven by a ballast is provided by a reactive power device in series between the AC supply and the ballast. The reactive power device provides a variable auxiliary voltage out of phase by 90 or 270 degrees with the current such that a smaller magnitude voltage is applied to the lamp. The dimming device has a switch to enable/disable dimming. When the switch is enabled, the voltage applied to the lamp is controlled by a half-bridge inverter with a pair of totem pole power electronic switches, along with a pair of DC series capacitors and a low-pass filter.
    Type: Grant
    Filed: August 26, 2004
    Date of Patent: August 12, 2008
    Assignee: e.Energy Double Tree Limited
    Inventors: Shu-hung Henry Chung, Ngai Man Ho, Shu-Yuen Ron Hui