Patents by Inventor Ryszard Malewski

Ryszard Malewski 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: 4914382
    Abstract: A high voltage measuring circuit for broadband measurement of transient signals occurring in high voltage apparatus. The measuring circuit is housed in a shielded housing having an input sensing circuit for connection to a capacitive grounded tap of the high voltage apparatus. The sensing circuit is connected to an output circuit through an electrical shielded connection. The measuring circuit generates output signals which are replicas of the transient signals appearing on the bushing of the high voltage apparatus. The broadband of the measuring circuit extends over a frequency range of from about 1 Hz to 1 MHz and has a signal level higher than background noise.
    Type: Grant
    Filed: October 27, 1988
    Date of Patent: April 3, 1990
    Assignee: Hydro-Quebec
    Inventors: Jean Douville, Ryszard Malewski, Louis Lavallee
  • Patent number: 4825153
    Abstract: In order to minimize the effect of return current flow on a current measuring shunt, the present invention proposes a shunt having a compensation circuit to compensate for the asymmetrical effect of such return currents. Such compensation is provided by two measuring circuits which are to measure the voltage drop across the shunt, and each circuit is located in a median plane of the shunt. The path of each of these measuring circuits is optimized and established in the calibrated configuration of the shunt. These parallel measuring circuits also have their inputs and outputs connected together respectively. Particularly, the present invention relates to shunts having a tubular or rectangular configuration and including such compensation circuits.
    Type: Grant
    Filed: March 4, 1987
    Date of Patent: April 25, 1989
    Assignee: Hydro-Quebec
    Inventors: Ryszard Malewski, Marc Leclerc
  • Patent number: 4743846
    Abstract: In order to reduce errors between the measured current by a rectangular shunt and the shunt output signal voltage, such errors being due primarily to skin effect and the proximity of the shunt to the current circuit to be measured, the present invention proposes a shunt having a measuring system which compensates for these error causing effects. The shunt utilizes a measurement circuit following a path which reduces the difference between the potential produced across the shunt and the form of a current which passes therethrough. The path of the measuring circuits starts from the center of the resistive material of the shunt and progresses towards the outer surface of the resistive material in accordance with a function which is non-monotonic and which can even follow a curved path. More particularly, the shunt has a rectangular geometry to permit the maximum heat dissipation which is produced by the shunt in its continuous operating mode under ambient conditions.
    Type: Grant
    Filed: March 18, 1987
    Date of Patent: May 10, 1988
    Assignee: Hydro-Quebec
    Inventors: Marc Leclerc, Ryszard Malewski, Jean-Paul Thivierge