Reactive Power Requirements of Grid Connected Induction Generator in a Weak Grid

: Induction generators are gaining the popularity due to its simplicity and no synchronization problem. However the major drawback of this machine is its additional reactive burden on the system, where it is connected. In this paper an attempt is made to explore the performance of a grid connected induction generator (GCIG) due to weak grid conditions i.e. voltage and frequency fluctuations. Iterative model developed by the authors is used to predict the reactive burden of the generator due to voltage and frequency fluctuations. The comparison between experimental and simulated results proves the validity of technique proposed. Further proposed modeling is also used to include the effects of saturation. Key-Words-: Grid connected induction generator, Iterative technique, Magnetizing reactance, Saturation, Weak grid Nomenclature E1=Air gap voltage per phase fs=System frequency I1 = Stator current per phase I2= Rotor current per phase Im= Magnetizing current per phase pf = power factor Pfw = Friction and windage losses. Pg = Air gap power. Pin = Input Power. Pm = Mechanical Power. Pout = Output power. Prcu = Rotor copper losses. Pscore = Stator core losses. Pscu = stator copper losses. R1 = Stator resistance per phase R2= Rotor resistance per phase referred to stator s=Operating Slip V1=Rated terminal voltage per phase or grid voltage X1= Stator leakage reactance per phase X2= Rotor leakage reactance per phase referred to stator Xm= Saturated magnetizing reactance per phase Xmu=Unsaturated magnetizing reactance per phase.