[ausev] DIY controller?

[Charlesvsi at aol.com]

Basic functions off the top of my head:
 1. sensors monitoring the relationship between accelerator pedal and  phase, 
amplitude,etc. of current going into motor, while monitoring phase shift  of 
back emf  that indicates how fast electric motor armature is going  around. 
2.  And algorithm that limits current to maximum current drawn  from 
batteries, and that monitors the voltage of batteries, (Ideally separate  readings for 
each cell of batteries ) . 
 
3. Then there is regeneration when accelerator pedal is let up some amount,  
recharging batteries begins, how much current and how fast to charge to 
maintain  long life and not overheat ( temperatures of cells monitored too since 
battery  life is reduced when at high temperatures).
 
4. And relationship between pressure on and position and rate of  change of  
accelerator and brake pedals. All related to actual speed of  vehicle to apply 
an algorithm to get maximum regeneration charge current but  with an override 
by brake pedal  if brakes are needed hard down to prevent  a crash.
 
5. A display system that shows charge voltage level of  battery pack, rpm of 
electric motor,vehicle speed in mph, forecast of miles to  go before needing 
charge. 
 
6.A circuit to calculate and warn about level of voltage in every cell of  
battery so they do not ever get discharged too low and flip over and get  
negative charge when charging. Displays to show all this data including  red flag 
warnings etc.
 
7.  A circuit monitoring electric motor speed  and temperature so  it does 
not overheat and run too fast, melting solder, destroying itself, and  displays 
showing all of the above when needed to warn driver to  not do something, etc. 
 
8. The charging circuit from 120 or 240 vac transformed to maximum voltage  
needed for battery charge, rectified to DC, and then circuits monitoring and  
then reducing ac input to not over charge batteries. And  a display  to show 
that it is all working. 
 
Probably more, but these are the same elements needed in Aircraft auto  
pilots, except we only need input and control on one horizontal axis instead of  3 
axis for airplaines.
 
9.  Probably a yaw or turn sensor to keep vehicle from turning too  fast with 
power on to roll over, based on the amount of unsprung weight on  wheels and 
axles, and the springing and shock absorber dynamics so it does not  yaw 
itself off of the road. 
 
I worked on the design of the B52 and Boeing 727 autopilots, but that was  in 
the 60's, so I probably don't remember a few details. 
Good luck with the controller. 
 
 
 
Chuck Simms


In a message dated 6/14/2008 8:42:41 A.M. Central Daylight Time,  
evehicle4me at hischopsticks.org writes:

What are  the "basic functions" that a controller needs to manage?


Quoting  Charlesvsi at aol.com:

> Good luck on DYI, We have a Honda Civic  Hybrid, I'm amazed at all the  
things
> the computer does so  well.
>  I was in Process Control Computer Systems for 38  years,  The control
> software is very complicated, especially in  life or  death   
> applications like cars.
>  Hopefully you can find some inexpensive  controller, with  sensors   
> etc, and menu
> driven software, so it will  run  all the basic functions, you will just h
ave
> to provide  specific information  about your vehicle etc.
> Have fun.  C.
>
> Chuck  Simms
>




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