Designing an Autotransformer

Hello, im trying to design an autotransformer using the simpowersystem toolbox but not having any luck. Does anyone know if this is possible using the multi-winding transformer element or some other element?

Thanks

Brandon

[Erlan Mynbai]

I also wanted to create an autotransformer if it turns out I'll say

[xinjie li]

i also need to create a 500kV three-phase autotransformer to power flow calculation. If there is any solution, please notify us. Thank you very much.