A study of the modified Kramer or asynchronous — Synchronous cascade variable-speed drive

  title={A study of the modified Kramer or asynchronous — Synchronous cascade variable-speed drive},
  author={M. M. Liwschitz and Lee A. Kilgore},
  journal={Electrical Engineering},
LARGE wind tunnels require a wide range of speed and accurate speed control and if their use factor is high, a high efficiency over the working range is desirable. Also minimum disturbance to the power system is important in many cases. To meet these requirements a speed-control system has been adopted which, while not new in principle, involved the solution of a number of interesting problems. The system as shown in Figure 1 consists of a wound-rotor driving motor (A) whose secondary winding… 

The development of variable-speed high-power drives for large wind tunnels

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SYNCHRONOUS machines, operating with a-c excitation on both stator and rotor are used in many applications, for example, as induction frequency converters, as power and instrument Selsyn drives, and

Damping and Synchronizing Torque of the Double-Fed Asynchronous Machine

  • M. M. Liwschitz
  • Engineering
    Transactions of the American Institute of Electrical Engineers
  • 1941
I. Introduction THE double-fed asynchronous machine has become important in recent times as fan drive with wide speed range. The system consists of five main machines and the fan (see figure 1). It

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The straight mathematical analysis of the damping problem on the synchronous machine leads to very complicated results. From these results, the conception of the phenomena occurring in the machine is

Variable-Speed Drive for United States Army Air Corps Wind Tunnel at Wright Field, Dayton, Ohio

THE machinery manufacturers are being required to solve many design and production problems in connection with our national-defense program. All electrical manufacturing companies are exerting