Make Mine Electric Porche Speedster replica


EV conversion classes: [index]

DAY nine: Oct 11 th, 2008 - Saturday.

[Sorry - no photos- forgot my camera again...!]

Day nine of the Santa Rosa Junior College Course -

Half way through and today we only had about half the class there. Since there were so few people there, and it seemed to get even less as the day wore on we didn't get a chance to check in at the end of the day. Everybody just sort of dribbled out.

However as far as I could see from sticking my nose under the hoods of the other cars this is what seemed to be happening:

Don's car:
Through a bit of good luck, they have acquired 20+ 3.2v Lithium Ion Phosphate batteries. Work was started designing and building frames to hold the batteries. The motor would need to be rebuilt, but may not be worth it. The car is still up on stands just to make it easier to work on, but all non-eve suspension, brake and steering work is now complete.

Team Harley :

Took the day off as the principals were in Los Angeles.

Team Michelle:

We appear to have revived at least 10 of the batteries through overcharging, the drawing them down again. It is a long and slow process but has the aim of saving Micheles thousands of dollars worth of new batteries.

>>> cont next column >>>

<<< Back to day eight

Team woody:
Continued wiring up the switches. Now the gnition switch can be turned on, and if the main consol switch is put into reverse, the reverse light comes on and the buzzer sounds - Whoopee!. Also a button when pressed on the "dashboard" will cause the brake-light to come on. This was mainly just to ensure that we had a working light. Eventualy, when the motor is regenerating power, it should also cause the brake light to come one. Apparently, the regeneration draws so much inertia out of the vehicle's motion, that it is much the same as hitting the brakes. Peter reports that in his own car he rarely needs to touch the brakes.

Peter has found a Battery Management System (BMS) that simply ensures that two batteries next to each other are brought to the same voltage. By adding this to every pair, there is a cascading effect that ensures that every battery in the entire pack ends up at the same voltage. Different voltages in the batteries major problem in Michelle's car as we found we checked them on the first day.

The Team also fitted an adaptor plate and flywheel pressure plate to the AC motor. This is much more fiddly as than it should be because the method of joining the output shaft to the flywheel it such that it can introduce a wobble. Multiple attempts and measurements with a dailometer had to be taken. Ideally the work should take place on a solid and exact work surface, whereas we had the motor balanced on wooden blocks. However, the lesson was well learned.

Ed's Car:
The main panel holding all the relays was installed and all the wiring worked on. The Controller is in, and it is starting to look like a real EV under the hood. The batteries were being charged in parallel to bring them all up to the same level.

On to day ten>>>

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