Lee, Good comments. You and I could sit and discuss some parts of your comments; however, overall I thank we agree.
________________________________ From: Lee Hart <[email protected]> Sent: Saturday, November 12, 2016 7:23 PM To: ROBERT Subject: Re: [EVDL] Cheap L2 charging in parking places: Bolt EV's In Production ROBERT wrote: > Lee, I may have incorrectly stated the frequency of the EV1 induction > charging. I showed the nameplate data as "Charge Port CP7100, 475VAC > Peak, 22A AC Max, 400 Hz, 6.5 KW Max Output Power, Manf Date July 1996." > I should have showed "Charge Port CP7100, 475VAC Peak, 22A AC Max, 6.5 > KW Max Output Power. This is the info on the main nameplate. Hi Robert, Schott Power Systems made many of the EV1 Magnecharger parts and modules for GM and Hughes (including the one on the eBay link you provided). I worked for them at the time, designing battery chargers and power electronics. The "400 Hz" you referred to was the maximum AC input frequency. Though 60 Hz was normally used, it could also be used on 400Hz which is found in some military and aircraft systems. Hughes is a major in these markets, so it was normal for them to specify 400 Hz on things they designed. The Charge Port module in the eBay listing you provided is an example; it was built by Schott Power Systems. It's basically a rectifier and DC/DC converter. It takes high frequency AC from the car half of the paddle transformer, rectifies it, and converts it to the voltage commanded by the battery charge controller. The input frequency range for that particular module isn't the same as all modules. The frequency range varied, depending on the power level of the particular charging components. That particular one was for 6.6KW. They ranged from 3KW to 100KW. The CP7100 Charge Port had the half of the transformer that goes in the car, along with the associated mechanical parts and shielding. The rectifier was located in the separate Charge Port controller. Again, there were different ones, depending on what maximum power level the setup allowed. > Lee, I was making the following points in my e-mail concerning the > installation of a large number of EVSEs in a parking area: > > (1) (2) The installation will be very expensive... Our present EVSE setup is expensive and unreliable. But, it could be argued that the auto and utility companies *want* an expensive and unreliable system. It's a way to discourage EVs. > (3) The system will have a low utilization rate because vehicle will > be parked for an extended periods True, if each EVSE is a high-power setup, and gets used in a place where cars will get parked for long periods of time. > (4) System security is low because of scammers and no local oversight I'm not sure there is any real problem with scammers. Around here, we've had free outdoor AC outlets for 50+ years, and I've never heard of any problems with people "stealing" power. Sure, a homeless person might charge their cellphone from one of these outlets; but so what? The power used is a penny or less -- too small to charge for. PS: Putting that nice big expensive copper cord on every EVSE is an invitation for copper thieves. If they only provided NEMA receptacles, there wouldn't be anything to steal. > (5) Not a safe system because of a possible pool of water or vandalism. Well, we've mandated GFCIs for decades on all outdoor outlets. They seem to solve the safety problems. PS: Normal GFCI's have a 5ma limit. That's low enough to be safe for even children and the infirm. The auto companies have pushed for a 20ma limit instead. 20ma *probably* won't kill a healthy person, but certainly could a younger or less healthy individual. > Due to the above points, the installation of a large number of EVSEs in > a parking area (1) is not an efficient use of equipment, (2) has low > system security, (3) unsafe system and (4) is not a good use of capital. > > My suggestion to solve the problem was for everyone to charge at home > with a NEMA type outlet or use an induction type system in a parking area. I'm with you; the present EVSE model is not a good choice for widespread adoption. Regular NEMA outlets look like a better choice. > An induction type system reduces the installation cost because of a > reduction in the size of the electrical distribution system. With an > induction coupled system, the main source can sense the presence of a > vehicle or if a vehicle requires power; therefore, the main source can > be sized to the utilization rate. In fact, Schott did have a version of our 100KW charger that could charge multiple vehicles at once. It divided the power between them. An induction charging system will be *more* expensive than a conductive one. The Magnecharger was very expensive! But it was virtually hand-made, and seriously over-designed to high standards. I think that with mass production and reasonable design standards, a magnetic charging system could be only *slightly* more expensive than a conductive charging system. However, it would require tight cooperation between the car companies to keep them compatible. That is a FAR bigger problem than the engineering challenges. > This cannot be done with an EVSE system. Yes, it can. The regulations didn't expect it, but it could be made to work anyway. > The system is safer because it is not effected by water > and is secure from vandalism. The safety benefits are dubious, since the conductive systems don't energize the cable until after the connection is made. And the Magnecharger cable is just as vulnerable to theft and vandalism. The best setup is just to have a NEMA receptacle on the "charging station", and the cord and charger in the EV being charged. Unroll your own code, and plug it in. If it's stolen, your insurance would cover it like any other act of vandalism (like a broken window, etc.) > An X10 system (PowerLine Transmission) will not work in an industrial or > commercial environment The consumer-grade X10 was optimized to be cheap, not robust. But there *are* industrial-grade setups that work over the power line. > RF is not reliable in a structure with high levels of electrical noise It's reliable enough for a car parked right next to a charging station, with nothing but air between them. -- The reasonable man adapts himself to the world. The unreasonable man persists in trying to adapt the world to himself. Therefore all progress depends on the unreasonable man. -- George Bernard Shaw -- Lee Hart, 814 8th Ave N, Sartell MN 56377, www.sunrise-ev.com<http://www.sunrise-ev.com> The Sunrise EV2 Project<http://www.sunrise-ev.com/> www.sunrise-ev.com The Sunrise EV2 Project Homepage. Welcome! We are a group of dedicated electric vehicle enthusiasts whose goal is to create an affordable, high performance electric ... -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20161113/96fdda06/attachment.htm> _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org Read EVAngel's EV News at http://evdl.org/evln/ Please discuss EV drag racing at NEDRA (http://groups.yahoo.com/group/NEDRA)
