Patents by Inventor Alexander Nuss

Alexander Nuss 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).

  • Method and apparatus for determining a fault current portion in a differential current
    Patent number: 8854846
    Abstract: When determining a fault current portion IF in a differential current idiff(t) measured by an inverter, an AC voltage uAC(t) applied to an AC output of the inverter is measured and a periodic reference function y(t) of alternating sign is generated as a function of the measured AC voltage uAC(t) in order to determine an AC fault current portion IFAC in the differential current idiff(t). The differential current idiff(t) is multiplied by the periodic reference function y(t), and the product of the differential current idiff(t) and the reference function (y(t)) is averaged over an integral number of periods of the reference function y(t). The reference function y(t), at least for one operating state of the inverter, is generated with a predefined phase offset with respect to the measured AC voltage uAC(t) and/or with a frequency which is an integer multiple of the frequency of the measured AC voltage uAC(t).
    Type: Grant
    Filed: October 15, 2013
    Date of Patent: October 7, 2014
    Assignee: SMA Solar Technology AG
    Inventors: Alexander Nuss, Christian Bode, Wilfried Groote
  • Method and Apparatus for Determining a Fault Current Portion in a Differential Current
    Publication number: 20140043880
    Abstract: When determining a fault current portion IF in a differential current idiff(t) measured by an inverter, an AC voltage uAC(t) applied to an AC output of the inverter is measured and a periodic reference function y(t) of alternating sign is generated as a function of the measured AC voltage uAC(t) in order to determine an AC fault current portion IFAC in the differential current idiff(t). The differential current idiff(t) is multiplied by the periodic reference function y(t), and the product of the differential current idiff(t) and the reference function (y(t)) is averaged over an integral number of periods of the reference function y(t). The reference function y(t), at least for one operating state of the inverter, is generated with a predefined phase offset with respect to the measured AC voltage uAC(t) and/or with a frequency which is an integer multiple of the frequency of the measured AC voltage uAC(t).
    Type: Application
    Filed: October 15, 2013
    Publication date: February 13, 2014
    Inventors: Alexander Nuss, Christian Bode, Wilfried Groote