DC Vs. AC – The Next Generation

It seems there are some new developments in the home conversion EV field, and I thought it would be a good idea to chronicle some of them.

DC

Paul and Sabrina’s EV Open-Source controller, the “ReVolt” (Warning: Massive thread!) has come on leaps and bounds, and is now capable of massive voltages and (perhaps more importantly) amperages, and now has a nicely modularised design so you can build and use your own custom power section to the standard controller board. It runs with both MOSFETs and IGBTs, and can be extended quite a bit. It also features real-time data readout and parameter adjustment.

AC

Not content with building a fantastic DC controller in the ReVolt, Paul and Sabrina are at it again, this time coming up with a 3-phase AC controller. It’s in the early stages at the moment, but the thread there also seems to be becoming a stopping off point for everyone making their own AC controller, which is good news! With this new controller, cheap AC motors already designed for EV use (Like the surplus Ford/Siemens motors out there, or a Toyota Highlander Hybrid axle).

Conversions of note

Gavin Shoebridge (AKA KiwiEV) may just be on the brink of starting KiwiEV 2, and I for one am rooting for him all the way. And if you haven’t already, you too can help! Not only is Gav’s e-book informative, it is practical and entertaining, with videos accompanying his experienced advice. He did a great job with KiwiEV 1, and you can learn from his mistakes. And when he does start KiwiEV 2, I will be following him every step of the way.

My own EV conversion

Erm… Yeah. If/When the Saskatchewan Government decides to finally take our old Chevy Corsica, and give us the $350 that’s promised under the “Retire your ride” scheme, I’ll have $350 (maybe) towards starting an EV.

“Why not use the Corsica?” I hear you ask (Well, I would if you did… you know what I mean…). Well, here’s an abridged list of things that need to be fixed on the Corsica before it’s really road-worthy:

• New springs/shocks/struts all round
• New brakes discs and pads, front and rear
• New transmission (Automatic, if converting to EV, will need to be switched to Manual)
• New power steering pump/lines
• New engine (Not applicable if converting to EV)
• New exhaust system (Also not applicable for EV conversion)
• New tyres (and possibly new rims)
• Patched/repaired bodywork
• Lots of rust removal
• New drivers seat mounts
• Underbelly patching

With this LONG laundry-list of faults, it would be considerably cheaper just to ditch the car and start anew with something else. So what is my ideal setup?

• Lithium Ion (LiFePO4) cells for main power storage
• Super/Ultracapacitor pack for load smoothing, improved regen and acceleration
• AC direct-drive system
• 400+V system voltage, handling peak power loads of 3,000A (Mainly from Ultracap pack)
• 260Ah capacity (minimum)
• Battery heating/cooling system (‘cause it gets MIGHTY COLD here in the Great White North)
• Optional demountable genset (For long distance travel, preferably diesel)
• 240V AC charging, at as high an amperage as I can get here, with the option of 110V opportunity charging (Block heater plugins, for example, would be a great way to sip some capacity as you shop)

I haven’t mentioned chassis, mainly because I am torn in that regard. On the one hand, something like an S10 would be easy to convert, and while it’s not the most aerodynamic of vehicles, it would certainly get the job done. On the other hand, something like a Mazda 3, or a Pontiac Wave, would be good for carrying capacity (Large dog + crate = need for fairly large “cargo” capacity) combined with light weight for better range. Though for sheer bragging rights, finding a Lotus Elise glider, or an RX8 to convert would just be too sweet, but unfortunately also too limiting (2 seats, and virtually no cargo area makes it difficult to justify), even as a daily driver. Where would you put the groceries, after all?

Of course, being in a rented house, in the hood, with a barely-1 car garage, and with a distinct lack of tools or experience, makes this all very pie-in-the-sky thinking at the moment. But you never know, if we get that lottery win, who knows what might happen?