Ferroresonance phenomena in transformer-capacitor compensators of combined action
- 1 — Associate Professor G.V. Plekhanov Saint Petersburg State Mining Institute
- 2 — Research assistant G.V. Plekhanov Saint Petersburg State Mining Institute
Abstract
Features of ferroresonance oscillations and methods of their elimination are considered on the example of transformer-capacitor system of longitudinal and transverse compensation used in power circuits of powerful electric motors, in power supply systems of ore-thermal and arc steelmaking furnaces. Based on the solution of Duffing's equation, the influence of current amplitude and system attenuation coefficient on the operating mode of transformer-capacitor has been determined. The stability area of the basic type of oscillations has been evaluated. It was found the existence of subharmonic oscillations and the influence of not only the amplitude but also the source phase on the appearance of anomalous modes caused by the relay effect and the phenomenon of self-modulation was revealed. It is shown that the elimination of ferroresonant oscillations is connected with maintenance of a magnetic circuit mode close to linear and with a choice of a damping coefficient from the condition of the maximum permissible value of the active resistance introduced into a line.