Monday, January 28, 2008

More Controller Goodies

I now have most of the controller working on the proto board, but the new design has a duty range from 8% to 95% which is good enough for me. My problem I have right now is designing the proper current limiting circuit so I don't over load the motor. I also have some problems actually putting this circuit on real hardware as my solder is ancient and does not really work on the boards I am using. So I need to acquire new solder with rosin core and then I can put together a pleasant looking prototype and do some testing on the motor. I will have a before and after photos of the controller, before being the prot0 board version and after being the nicer looking version.

The semester at school has started up again, which means mother loads of work, but I think I will be able to use my resources to build other aspects of this controller, and maybe even the machine shop to build my adaptor plates, motor coupling and battery boxes.

Sunday, January 20, 2008


The EVC-X104 is what I am calling my custom controller. It stands for Electric Vehicle Controller Experimental #4. The first prototype (X101) was not very effective and had a very small Duty range. (Around 80 to 95%) The second (X102) was a slightly better design, but I under estimated the current draw of the motor at 12 volts on the bench, and I ended up fusing my protoboard to some components! The third version (X103) worked great, but was very simple and had no current limiting or any of the features I wanted in my EV, so I moved on to X104 to start to add the great features I want. As I right now, I have my PWM control system and my Basic Stamp controller. Using the Basic Stamp controller as the PWM system takes too much out of it, so I have made a dedicated PWM controler circuit, and the Basic Stamp is going to control the throttle, current limiting and LCD display. The LCD display will give info such as Volts, AMPS, estmated range left at the current speed and a basic battery monitoring system.

Here is the basic specs I want out of this controller:

24 to 84 Volts
350+ AMPS
Inexpensive to build
LCD Status w/Volt and AMP meter built in
Current limiting
Cruise Control
Low/High Temperature Shutdown

Wednesday, January 9, 2008

Motor Has Arrived!!

The motor has arrived, and I did a bench test and everything seems in order. The motor appears to be in a new condition like stated, and sounds like nothing is wrong. I tied it down to a bench, and then used jumper cables and connected them to the motor and a 12 volt deep cycle battery. The battery is pretty shot, it has been sitting in the basement for at least 4 years, and had a charge of 1.5 volts when I found it. I have been attempting to revive it, and now it holds 40% of its charge, but it might need a water fill up and a few days on the charger to get anything else out of it.

I also have been working on a PWM controller, and I have enough of it done to work on a small 12 volt fan. I will be scrounging for more parts, and I might take another trip to Radio Shack to pick up some higher amp transistors and regulators so I can hook this thing up to the K99 for a real test run.