CPW GSG vs PSG (P=Power Line)

Hi everybody

i ve a question about simulating a coplanar Power-Signal-Ground structure in HFSS.
i m not sure how to assign a fixed potential of say 1V to the power line and subsequently define a lumped port.

moreover, should the boundary be radiation around the structure (λ/4 from each side)?

i would appreciate some guidance

Thanks

HFSS simulates AC signals, and the AC component of 1V is 0. So just treat the PSG like a GSG.