thanks for the help everyone.
It has to be with a VFD, no way arround it, because of security reasons I was told.
I have no idea if the VFD can be driven by PWM, the person Iam working for says that it has to be a pure analog signal from 0..10v, rest he told me is that the VDF its from SEW brand, afaik its a popular brand.
I asked a old friends help and we made a circuit using a ua741 opamp, I can now get it to 10v, probleam is that a PWM value from arduino lower than 4v the Opamp or circuit doesnt scale to that.
A value higher than 128 in arduino I can get a correspondent in the output of the opamp, lower its always 4v on the output.
I would buy the DAC product that was announced before but being in portugal makes it harder to aquire it.