self-exciting oscillation
Also known as self-induced oscillation, self-excited oscillation, self-excited vibrations, auto-oscillations
thumb|300px|Schematic representation of a self-oscillation as a positive feedback loop. The oscillator V produces a feedback signal B. The controller at R uses this signal to modulate the external power S that acts on the oscillator. If the power is modulated in phase with the oscillator's velocity, a negative damping is established and the oscillation grows until limited by nonlinearities.
~7 min read
Article
13 sectionsContents
- History of the subject
- Mathematical basis
- Examples in engineering
- Railway and automotive wheels
- Central heating thermostats
- Automatic transmissions
- Steering of vehicles when course corrections are delayed
- SEIG (self-excited induction generator)
- Self-exciting transmitters
- Examples in other fields
- Population cycles in biology
- See also
- References
thumb|300px|Schematic representation of a self-oscillation as a positive feedback loop. The oscillator V produces a feedback signal B. The controller at R uses this signal to modulate the external power S that acts on the oscillator. If the power is modulated in phase with the oscillator's velocity, a negative damping is established and the oscillation grows until limited by nonlinearities.
Self-oscillation is the generation and maintenance of a periodic motion by a source of power that lacks any corresponding periodicity. The oscillator itself controls the phase with which the external power acts on it. Self-oscillators are therefore distinct from forced and parametric resonators, in which the power that sustains the motion must be modulated externally.