Study on novel twelve-phase synchronous generator rectifier system

As for interior configuration of generator, six phase Y-Y armature windings is essentially equivalent to twelve-phase symmetrical windings displaced in turn by 30deg. Novel twelve- phase synchronous generator-rectifier system is developed in this paper. Characteristic of output voltage is analyzed in detail according to the star graph of slot potential, and then the design principle of armature windings in twelve-phase synchronous generator is provided. Utilizing the design of full-pitch-winding, the top-width angle of phase voltage waveform may greater than 120deg electric angle. It can be seen through theoretical analysis that the number of conductive rectifier diodes is not less than four. Based on a permanent magnet synchronous generator, field-circuit coupled models of twelve-phase rectifier system and six-phase Y-Y rectifier system are established separately in the Maxwell2D plus Simplorer soft environment, and the finite element analysis is accomplished. The analysis results validate the design principle of armature windings. Moreover, the number of rectifier diodes in twelve-phase synchronous generator-rectifier system is as same as that of six-phase Y-Y rectifier system, the current stress of rectifier diodes is reduced by half at least.