A RANDOM SUBSYNCHRONOUS RESONANCE IN A TURBINE GENERATOR SET

The electrical arc furnace (EAF) load is the largest load in power systems. Since electromechanical interactions between electrical loads and turbine-generator are seldom discussed, this paper investigates the torsional vibrations in turbine-generator shafts and blades subject to real and reactive power variations from a large-scale EAF plant. The transient power fluctuation of the load is randomly dramatic; nevertheless, most of the frequencies of the induced voltage flicker, generator delivering power and even electromagnetic torque are subsynchronous. Therefore such a continued stochastic disturbance can impose random subsynchronous resonant stresses on turbine mechanisms.