Many thanks Tim,
That's exactly what I need to know, I have come across a remark that said the solar wind can also be very low (it even stopped for 2 days in 1999?), I guess there is a plot somewhere in your links that shows the speed of the solar wind over the last decades, I'll have a look.
What happens at the heliosphere with the charged particles, is it a barrier, or will there be an acceleration? The Sun has a radial field, but I remember a "dancing skirt" animation where the neutral sheet (if the solar wind is charge neutral how can there be a neutral sheet?) is shown to change over time. What causes the drag on the field lines and again what happens at the outer boundary.
Another question is about current in the interplanetary region; we know there are charged particles and we know there is magnetism, but are there currents, in other words: do Birkeland currents or Birkeland ropes exist?
Thanks,
Louis.