Stability and other results of the rotating machine oscillator

✍ Scribed by C.V. Govinda Rao

• Publisher: Elsevier Science
• Year: 1959
• Tongue: English
• Weight: 713 KB
• Volume: 268
• Category: Article
• ISSN: 0016-0032
• DOI: 10.1016/0016-0032(59)90492-2

✦ Synopsis

A separately excited d-c. motor supplied from a d-c. series generator performs an unusual type of oscillation. For a reasonably clear understanding of the electromechanical phenomenon underlying this behavior, a nonlinear differential equation was developed and its complete solution was obtained by partially graphical and numerical methods. In particular Li~nard's method was adopted to examine the possibility of any periodic solutions. In this method periodic solutions are easily recognized by the presence of the so called "limit cycles," their number being equal to the number of such loops. Of these, one or more may give stable solutions and the rest unstable. In a set of investigations with which this paper is concerned two limit cycles in general were observed of which one and only one represents stable oscillations. The existence of these limit cycles itself was found to depend on various factors such as the polar movement of inertia, the shaft load, the brush shift, the circuit resistance and excitation. The paper confines itself to the discussion of the effects of variation of the first three factors and in the main the stability of oscillations. Any additional facts observed are also recorded.