PERFORMANCE AND ANALYSIS OF SYNCHRONOUS GENERATOR AND INDUCTION GENERATOR USING DIFFERENT TECHNIQUE

Abstract

A synchronous generator can generate both real and reactive power if sufficient amount of field and prime mover input is given. If the load at the consumer end varies the field and prime mover input has to be varied proportionally so as to keep the voltage and frequency to a rated level. Owing to the advantage like simplicity, less maintenances, brushless construction, low cost selfprotection ability and capability to generate power while driven at variable speed induction generators are preferred over conventional synchronous generator while considering power generation of renewable energy sources. If an induction generator is made to run at fixed prime mover input and out while connected to synchronous generator in parallel with it then the induction generator is bound to follow the synchronous generator. So in this case the induction generator is mostly used for supplying extra amount of real power to meet the consumer end load demand and thus facilitates synchronous generator to increase the power demand when connected in parallel to it. The major drawback of the induction generator is its poor voltage regulation. This is due to its unbalance of reactive power supplied by the excitation capacitors and that demanded by the load and the machine. Unbalance of reactive power supplied by excitation capacitor and also unbalanced demand of reactive power by load and machine causes poor voltage regulation in case of induction generator. So to have good voltage regulation an excitation control system for synchronous generator is designed to supply reactive power as the reactive power demand of the load changes. As the consumer end load changes the output frequency also changes. To maintain the frequency to a fixed value, frequency sensitive load controller is used and they vary in such a way that the two generators will see as if the loads connected at the ends are constant. This dissertation work presents simulation of parallel operation of synchronous and induction generator associated with ELC for maintaining the frequency as constant and along with the excitation controller so as to have constant voltage output.