Posted on 01/18/2020 9:24:27 AM PST by Olog-hai
“I wonder about the power loss in those inductive coils and the battery they charge. Such coils are basically the primary windings of a transformer. The secondary is on board the train producing AC to the Power Electronics Unit. The power losses of a transformer Then consider the power loss (20%) with the Power Electronics Unit which converts the AC to the DC battery charging voltage along with the cooling fans and other parasitic loads. Then consider the power losses from charging the battery and its discharge losses.
In the big picture, consider the power losses (about 5%) from the infrastructure needed to deliver the power to those inductive charging coils.”
IEEE requires at least 85%. Current systems are nominally 90%. The goal is 95% to make it on par with corded systems.
Did you find your error?
“3.3kW, 6.6kW or 20kW are not rates. 20kw per hour or per minute or per day would be rates. 20kw is a total.
“
Joules is the ‘total’.
watt is the ‘rate’.
definition: (joule PER second)
the SI unit of power, equivalent to one joule per second, corresponding to the power in an electric circuit in which the potential difference is one volt and the current one ampere.
I found what you are writing about. I was using conventional methods of inductive charging for my thinking. The Oak Ridge National Laboratory developed last year an inductive system that has 97% efficiency. The breakthrough came when they used a high frequency alternating current on the transmitting coil. The technology permits the transmission of power across a wide gap. This opens the ultimate objective of charging vehicles as they run down special lanes at highway speeds.
https://insideevs.com/news/340478/120-kw-wireless-charging-proves-97-efficient/
No need to be rude. Have you been Nottingham?
OK, so you were correct. Now answer me this: how long will it take to charge the battery on a cab at any of these rates? BTW, were did you get those rates? I don’t see them in the article.
Other questions: durability? How long will those charging plates last? IIRC, I read of a road installed in Germany that was to charge cars as they drove along. I believe it was a failure due to rapid degradation of the surface.
“No need to be rude”
I wasn’t.
” Now answer me this: how long will it take to charge the battery on a cab at any of these rates? “
Depends on the charging rate and how much they need to top off. But much less than the time they will sit in line.
“IIRC, I read of a road installed in Germany that was to charge cars as they drove along. I believe it was a failure due to rapid degradation of the surface.”
IIRC, that was a road that collected solar power and was not connected to EV’s.
TexasGator wrote: “Depends on the charging rate and how much they need to top off. But much less than the time they will sit in line.”
Analysis?
“What is a charger of this size going to do to any other electronics in the vehicle? Any nearby electronics on pedestrians?”
Nothing.
0.5 x 10 / 22 x 60 = 13 min
Facetious comment. Lighten up.
I am surprised how entertaining this thread ended up being. Plus an informative discussion on the efficiency of induction and principals of ac to dc conversion. You just never know where a thread is going to go. I think maybe Texas Gator is invested in an electric car endeavor because he takes it rather personal if I may say.
TexasGator wrote: “0.5 x 10 / 22 x 60 = 13 min”
A bit more detail please.
0.5 kwhr/mile
So how far will that 13 minute charge take you?
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