Vol 17, No 2 (2013) > Articles >

Determining the Air Gap Length of an Axial Flux Wound Rotor Synchronous Generator

Abdul Multi 1 , Iwa Garniwa 1 , Uno Sudibyo 1


  1. Department of Electrical Engineering, Faculty of Engineering, Universitas Indonesia, Depok 16424, Indonesia



The  air  gap  length  of  the  designed  axial  flux  wound  rotor  (AFWR)  synchronous  generator  is  determined  properly according to the design parameters. One of the distinct advantages of  an axial  flux (AF)  machine is  its adjustable air gap. An AF generator’s performance might be controlled by adjusting its air gap. The designed generator has a small-scale capacity that has 1 kW, 380 V, and 50 Hz. The windings are laid into slots made from laminated core. The slots are carved in the face of the stator and rotors. The generator has a single-double-sided slotted wound stator sandwiched between twin rotors. The effect of air gap changes on its  performance can be seen from the calculation results using the given equations. The results reveal electric quantities suited to the machine’s effective performance. The smaller the air gap,  the  greater  the  efficiency  and  power  factor  and  the  smaller  the  armature  current  and  voltage.  The efficiency  and armature current for 0.1 cm air gap are 85.30 % and 1.815 A, respectively.

Keywords: Synchronous generator, axial flux, wound rotor, air gap, efficiency
Published at: Vol 17, No 2 (2013) pages: 87-93

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