St Patrick's Day Research

The EV is never far from my mind nor from the thoughts of others. Recently, I started leaning more toward buying the controller, instead of dabbling in my own design. You see, there is a California tax credit (IRS Form 8910 and 8834) that definately provide an EV deduction for 2006 and will hopefully continue into 2007 and beyond. If I keep working on my own controller and fail to complete it by the end of 07, then I run the risk of wasting money on my own design when I could have purchased Otmar's Zilla outright. Alas, I now have tunnel vision on a 40-phase IGBT controller. I just can't shake the idea of building it or cooling it. Ponder a controller consisting of N x 555 PWM drivers, one for each IGBT. Each 555 is dT = (1/(N-1))*(1/18,000) seconds out of phase with the previous 555 PWM driver. Each PWM driver is further inhibited by a single thermocouple that zeroes the output if the IGBT temperature exceeds a threshold. See this circuit.

On the subject of cooling, thanks again to the EV Forum for offering up great ideas. After much discussion, it sounds like Flourinert, Mineral Oil, Distilled Water are the top three heat transfer liquids.

On the topic of adaptors, I received a great deal of advice from Cliff Wiley, who converted a Ghia using a Prestolite MTC-4001. Jim Schinnerer send the link ($650) and this for adaptor sources. Jim also recommends that one "spend more on batteries and less on the motor." Electro Automotive in Northern California has a long history of supplying EV parts and has several links to adaptors and their prices ($750). It is not entirely clear to me why (or if) the Electro Automotive adaptor is worth $100 more than the EVparts adaptor.

On the topic of batteries, dhavranek sent me a link to his EV at http://home.comcast.net/~dhavranek/, which looks great. He used 8V T890s and recommends against it, due to their volume. I am still looking for an alternative to Optima Yellow tops. NiCad? NiMH?

On the topic of motors, Jim Husted of Killacycle fame send me a link related to his excellent work. I am a big fan of Jay Donnaway's Ghia conversion, which contains Jim's Gamera 9. Jim is not too far from Prineville, Oregon, so I hope he can help with a refurb by July 4, 2007.