The Dynamics of Capacitive Compensated Grid Connected Squirrel Cage Induction Generators

A wind energy system connected to a series compensated line is studied. The series compensation enhances the power transfer capability but could lead to various forms of oscillations and probable instabilities. Computer simulation is used to show the dynamics of the system and establishes a safe operating region for the studied system. The qd per unit dynamic model of the system is developed while the turbine - generator sub - system is modeled also in per unit using the two mass mechanical model. Simulation studies and steady state analysis of the system are performed including the small signal eigenvalue analysis. It is shown that at high negative slip, the electromagnetic torque and hence the available power increases with increasing level of compensation. However, as the slip decreases to zero, the electromagnetic torque converges to a common value irrespective of the compensation level. For stable operation, increasing compensation level, required an increasing slip.