Resources Contact Us Home
Coordinated load commutated inverter protection system

Image Number 19 for United States Patent #4475150.

A fault protective system for a load commutated inverter motor drive including an AC to DC source side converter coupled from an AC source to a DC to AC load side converter via a DC link circuit and wherein the load side converter supplies AC power of varying magnitude and frequency to the synchronous motor load. A pair of microcomputers interlinked by a common digital memory respectively control the inverters and interface with hardware type sensor means for detecting the occurrence of a plurality of different types of faults. Additionally, a number of stored instructional sets or programs are respectively included in both microcomputers to detect by software means another plurality of faults. The detection of a fault on either side of the link circuit is communicated to the respective computer which subsequently communicates with the other microcomputer to effect a coordinated protective action in response to thyristor cell failures, circuit failures, and abnormal operating conditions. Cell failure faluts include those instances where a thyristor cell actually fails due to an open or short circuit as well as those cases where a cell fails to commutate properly due to firing strategy problems. Cirucit failures include open and short circuits both in the supply line and the motor leads, while abnormal operating conditions involve such things as low line voltage or excessive motor voltage.

  Recently Added Patents
Data feed management
Active matrix substrate, method for manufacturing same, and liquid crystal display apparatus
Computer-implemented method of constructing a stock index using index rotation
Power management implementation in an optical link
Controller for flexible and extensible flow processing in software-defined networks
Direct chemical vapor deposition of graphene on dielectric surfaces
Method and assembly for determining the temperature of a test sensor
  Randomly Featured Patents
Distribution marketing piece
Process for dimerizing olefins
Wrinkle-preventing passive roller system for printing machines
Filter insert for a storm drain
Method of manufacturing injection molding manifold having a melt passage with an elbow
Informing a user of a content management directive associated with a rating
Audio processing method and sound field reproducing system
Air jet sieve device
Lightweight conditioning roll