Comparative analysis of technical and economic characteristics of generator sets on the basis of synchronous and asynchronous generators

The paper considers one of the ways of  improving the technical and economic performance of ship autonomous electrical plants by using asynchronous generators with capacitor excitation instead of traditional generator sets with synchronous generators.   The following advantageous characteristics of an asynchronous generator in comparison with a synchronous one are defined. An asynchronous generator has smaller dimensions and weight as well as a simpler construction of the squirrel-cage rotor; there are neither multiturn rotor windings, nor sliding contacts and rotating semiconductor elements, nor current insulation on the rotor, which increases the limiting heating temperature and provides high limit speeds of the rotor. The higher efficiency of an asynchronous generator due to the small value of rotor resistance ensures its economy.  The asynchronous generator has a sinusoidal waveform of the generated voltage, symmetry of the three-phase voltage at an uneven load. Rapid attenuation of currents in the case of loss of excitation ensures the safety of short-circuit modes for the asynchronous generator. The regulation of capacitive excitation of an asynchronous generator along the stator circuit allows the creation of high-speed and invariant voltage stabilization systems. Simplicity and safety of paralleling, absence of rotor oscillations at significant changes in the load ensure the stability of parallel operation in multimachine power plants.