Paul & Sabrina's cheap DIY 144v motor controller

[MPaulHolmes]

Oh! Hondo's controller broke, so we need to figure out what happened. He said it looks like a mosfet may have blown. He's mailing it to me, so we'll get to the bottom of it. It may have had something to do with a heater somehow. I'll take pictures and post them here. It will be interesting to see if it's somehow related to a grounding issue, or maybe I just did a crappy soldering job? I can't wait to find out!

[dave koller]

Well am done reading the thread - whew!
Great job by all... It is a collection of trial and error - failure and fix - Great Humor and slight of hand

I did most of what you have done in software, in hardware lol for my build and, of course, I added voice ( robot building habit ) -

Adam - you would like my wifi robot and mouse control interface with video cam.

Jack - I have a new respect for your controller I did not see on DIY forum.

Ben - I was the first guy to identify your vacuum pump at MREA

Paul - I have dialup here in the northwoods but I managed to "track" your progress by looooooong downloads of video lol... A great job!!

What a ride.....

[sawickm]

Originally Posted by MPaulHolmes

For the LEM, I'm going to use a surface mount lem that just has to be calibrated by spacing it away from the bus bar just right. Then it picks up the magnetic field of the bus bar. My friend that did the layout for the controller is going the surface mount LEM route, and it's working really really well for him. It's nice to have such creative friends!

Paul,

Is your friend using a Sentron CSA-1V Current Sensor as the LEM replacement CSA-1 it is an 8 pin SOIC package too.

I suggested that part to Adam awhile ago, it can handle 2000A. Sentron even has a reference design PCB that attaches directly to the busbar.

-Mark

[MPaulHolmes]

Hi Sawickm! Yes, that's exactly the type of hall sensor my friend is using. Well, I'm not 100% sure if it's the identical part number, but it's the same company. I ordered 10 of a similar part, but from LEM, and those suckers should be here in a week or 2. I can't wait! ya!

[sawickm]

Hey Paul,

I thought that was the part you were talking about!

I can’t wait to see you interface those to the controller! I’ll bet that you ordered them from GMW Associates - Sentron CSA-1V Hall Effect IC - Price list . At $4.95 each in 10 qty they are a good buy. The AN_121KIT is the off the shelf PCB that mounts directly to the busbar at $35.00.

It would be nice if the CSA-1V circuit could be mounted on the power PCB behind the B+ busbar.

[MPaulHolmes]

Actually, I'm going to be super sneaky, and make my own little etching with the mill. My friend had to mount his 0.3" above his bus bar to get a range of 600 amp. We'll see what happens. Mine isn't actually the Sentron, but from the LEM company. They are basically the same thing though, but I'm sure will calibrate differently.

[sawickm]

Originally Posted by MPaulHolmes

Mine isn't actually the Sentron, but from the LEM company. They are basically the same thing though, but I'm sure will calibrate differently.

Paul,

The spec for the Sentron CSA-1VG says that it is functionally similar to the LEM FHS 40-P/SP600 and the Melexis MLX91205. All three of them are SOIC8 packages, but I'm not sure how they differ when calibrated.

-Mark

[steiner]

Paul,

Will the 1000 amp version still use the same control board?

I need to build a 1000 amp controller that will drive a seperatly excited motor. The field coil only needs 50 amps so I thought about building your controller for the armature and adding a small second controller to drive the field. I am just not sure if the small controller needs variable current as a function of pedal position or just off and on as the pedal is pressed. I don't plan on doing any field weakening but I do want it to be an H-bridge to allow reversing without a contactor.

[MPaulHolmes]

No the control board will be different. You have to use a different microcontroller that has multiple pwm outputs and programmable dead time. I'm going to use a dsPIC30F4011, which has 40 pins available for whatever. It's going to have CANbus and RS-232 serial interface. I can't wait to test CAN to like 1Mbps. It's important to send messages like "display the letter r" in a femtosecond. hahaha.

Also, it will have 4 isolated dc-dc supplies instead of just 1 like it is now. The high side and low side have to have their own isolated supplies.

[jackbauer]

Paul , how difficult would it be to configure an unused pin on the mega168 (perhaps one of the pins on the icsp header) to go high when the throttle is pressed and go low at zero throttle? Its for my shunt field control setup i'd rather not have the shunt continuously drawing 4 amps when stopped or at zero throttle.