Patents by Inventor Michel Pieter Alfons VERHULST

Michel Pieter Alfons VERHULST 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).

  • Variable speed drive system, method for operating a variable speed drive system and method for refrigerating a hydrocarbon stream
    Patent number: 9479103
    Abstract: A variable speed drive system employing an electric motor and a frequency converter arranged between an AC power source and the electric motor is operated. The frequency converter functions to convert AC power obtained from the AC power source at a source frequency to converted power at a variable drive frequency. A mechanical assembly can be coupled to the electric motor. Electric modulation circuitry is provided interacting with the frequency converter. It is arranged to impose fluctuations, independently from any torsional excitation in the mechanical assembly and the AC power source, in the inter-harmonic frequencies of inter-harmonic currents generated in the frequency converter.
    Type: Grant
    Filed: August 29, 2013
    Date of Patent: October 25, 2016
    Assignee: Shell Oil Company
    Inventor: Michel Pieter Alfons Verhulst
  • VARIABLE SPEED DRIVE SYSTEM, METHOD FOR OPERATING A VARIABLE SPEED DRIVE SYSTEM AND METHOD FOR REFRIGERATING A HYDROCARBON STREAM
    Publication number: 20150303855
    Abstract: A variable speed drive system employing an electric motor and a frequency converter arranged between an AC power source and the electric motor is operated. The frequency converter functions to convert AC power obtained from the AC power source at a source frequency to converted power at a variable drive frequency. A mechanical assembly can be coupled to the electric motor. Electric modulation circuitry is provided interacting with the frequency converter. It is arranged to impose fluctuations, independently from any torsional excitation in the mechanical assembly and the AC power source, in the inter-harmonic frequencies of inter-harmonic currents generated in the frequency converter.
    Type: Application
    Filed: August 29, 2013
    Publication date: October 22, 2015
    Inventor: Michel Pieter Alfons VERHULST