Abstract
A shaft generator system, which consists of a shaft generator, a rectifier, an externally commutated thyristor inverter, an ac reactor, and a synchronous condenser, is being increasingly used mainly in large ships. Conventional type of the shaft generator system has a fundamental drawback of involving a large amount of harmonics in the output voltage waveform.
In this paper novel and simple circuit configurations are proposed to realize a shaft generator system without output voltage distortion. In order to cancel out the subtransient inductance of the synchronous condenser, by which voltage distortion is caused in the event of commutation of inverter, we propose a new system equipped with a duplex reactor instead of ac reactor. A set of system equations for the proposed system is then given, and the steady-state characteristics of the system are discussed. The effectiveness of the proposed system was confirmed with the experimental investigations. The apparent power of the duplex reactor is also discussed.
