From: Andy Fierman <andyfierman@si...>  20110627 13:31:25

Oops. My misunderstanding. If K=1 is invalid then an ideal AC transformer cannot be made using the mutual inductors. Hence, isn't that a case for keeping the ideal DC transformer? Then an ideal AC transformer can be realised by putting an inductor across the primary. Even so this is not a complete solution because any dc resistance added to this inductor would then generate a DC output from the secondary for a DC input to the primary. Would a preferred solution not be to allow the range for K to =+1 and 1? I know QUCS is not SPICE but most other simulators allow k=+/1. Cheers, Andy. signality.co.uk On 27 June 2011 14:13, Carsten Koegler <ckoegler@...> wrote: > Hi Andy, > >> I have found on QUCS 0.0.16 that the mutual inductor model will not >> allow k=1 even though the error message when setting k=1 states that >> k=1 is valid: >> >> "checker error, value of `k' (1) is out of range `]1,1[' in `MUT:Tr1'". >> > > The error message states, that 1 and 1 are invalid. The endpoint of the interval are excluded. > see > http://en.wikipedia.org/wiki/Interval_(mathematics) > > Carsten > 