A wind turbine transformer resonance can occur due to high frequency transients at its terminal i.e.; under its energization through a length of cable. Occurrence of resonance can be addressed by a sophisticated transformer design procedure. The goal is to obtain an optimum design capable of controlling the frequency response of the winding in such a way to avoid occurrence of any resonance under transient conditions. Three insulation clearances parameters which are employed for the wind turbine transformer winding design have been investigated in design of a (800 kVA, 690/20,000 V) wind turbine transformer to determine effect of their variation on its frequency response. It is shown that the best way to control the frequency response is to adjust the distance between LV and HV windings while maintaining other clearances as short as possible; realizing limitations enforced by other insulation constraints. Multiple-design algorithm is also investigated and found to be effective in control of the amplification factor under resonance frequency condition. Finally a 20 kV/690 V-400 kVA dry type wind turbine transformer is employed to verify the promising features of this design methodology, through comparison of the frequency responses of the real transformer against the model.