On 28/07/2014 09:21, Huge wrote:
On 2014-07-28, John Williamson wrote:
On 28/07/2014 02:06, The Natural Philosopher wrote:
On 27/07/14 23:49, Tim Watts wrote:
I thought it was more the issue that you cannot phase lock France and
the UK? So DC is a natural choice if you have to re-invert it. And if
you have to do that, might as well transmit in DC too.

Not saying your reason is not a good reason - I just thought it was a
secondary reason to a fairly immutable primary problem.

No. I visited the first link to france at the UK end and the issue is
primarily one of losses

'we can draw an arc for 30 minutes off the capacitance in that cable'

To drive that capacitance takes a LOT of out of phase current and that
suffers resistive losses.

Big ones

The main AC losses are inductive and leakage by capacitance to ground,
not resistive.

That's what they told me when I took a group of trainee electrical
engineers to the site a few decades ago. The guy was actually quite
surprised when none of them could answer the question he asked of why
they did it the way they do, but the coach driver could.

The coach driver had done the tour before ...


No, the coach driver is the son of an electrical engineer who
specialised in the heavy stuff, and had been playing with electronics
since he was about 11 years old.

--
Tciao for Now!

John.