Title :
A Study of the Modified Kramer or Asynchronous-Synchronous Cascade Variable-Speed Drive
Author :
Liwschitz, M.M. ; Kilgore, L.A.
Author_Institution :
The Polytechnic Institute of Brooklyn, Brookly, N. Y.; Consulting engineer for Westinghouse Electric and Manufacturing Company, East Pittsburgh, Pa.
fDate :
5/1/1942 12:00:00 AM
Abstract :
Several large wind-tunnel drives recently built have involved a system of speed control which has seldom been used commercially, and a number of new problems had to be solved. The system consists of a wound-rotor induction motor whose slip rings are connected to a synchronous motor driving a variable-speed d-c generator which feeds a constant-speed d-c-a-c set putting the major part of the secondary power back into the line. This drive is found to be very efficient and particularly suited to very large fan or pump drives where a wide range of speed is required. The problems of steady-state and dynamic stability are discussed and some novel methods of analysis given.
Keywords :
Automatic control; Automatic generation control; Feeds; Frequency synchronization; Induction generators; Induction motors; Power generation; Synchronous motors; Velocity control; Voltage control;
Journal_Title :
American Institute of Electrical Engineers, Transactions of the
DOI :
10.1109/T-AIEE.1942.5058524