Paul & Sabrina's cheap DIY 144v motor controller

[princeton]

Originally Posted by ElectricZX2

If Ben decides to pass up the opportunity I have a car with a 9 inch motor and 132 volts in it that has a dead curtis 1231c in it. I promise that when I kill it I won't dance on the ashes .

It warms my heart to see that people are willing to destroy something for a good cause. Actually, I'm a bit worried about the motor and battery used for the test since my controller doesn't have any current limiting. If the motor gets bogged down, it might burn up the brushes. I can build another controller for about $400 in parts but a motor or battery pack might cost someone a lot more than I have invested.

[Georgia Tech]

Hey guys!
whats the updates on the Synchronous controller? Yall got boards back yet?

[MPaulHolmes]

hahaha. OK, I got a weeee bit distracted by the AC controller. It won't take much to change the layout for the SR board. But this is an excellent opportunity to debug the SR board to, since the AC board is all of them rolled into one.

[Georgia Tech]

I thought some of these vendors would sample me parts to give to you but I have not heard back from them.... What do you need debugging?

[The Toecutter]

I know someone near me who purchased this kit.

He assembled the control board; the yellow error light flashes when he tries to drive a single MOSFET with it for testing, and he cannot figure out why the yellow light is blinking. Further, he downloaded RTD explorer to his machine, and the program refuses to respond when the potentiometer is used to simulate acceleration.

I checked the controller over and it looks to have been assembled and wired correctly. Everything is in the proper location, and the soldering job was very clean. None of the components have ever smoked or burned. We spent the day trying to trouble shoot it.

He has not yet connected the control logic to the power setup. He has simply tried to drive a small MOSFET, and has not had any luck due to the error light blinking.

What do you think is the most likely culprit for the error?

[MPaulHolmes]

The lights flash rapidly only when throttle or current is out of the expected range. The control board gate driver output should not be connected to anything just yet. I'm not an RTD Explorer expert, so I can't really help there, but you can measure the resistance of your 5k 2 wire pot. Zero throttle should be close to 0 ohms. Full throttle should be close to 5k Ohms. Now, one reason the current sensor could not be working is if the 4 wires that go to the sensor aren't wired in the right order to the control board. Could you guys take a picture of the 4 current sensor wires connected to the control board, and a picture of the 4 wires to the current sensor?

[The Toecutter]

When should the control board gate driver output be connected?

Does the control board have to be connected to the power board in order to test if the control board is working properly?

Also, on the pdf file showing the assembly process, you never specify where the ground wires from PH1 to PH2 go to. Do those need to be connected to the ground on the ground on the power board before testing can be done?




I'm interested in purchasing one of these myself, and upgrading it to match the high voltage capabilities of my motor. Also, how is current limiting done with this device? Is it programmable by chance?

[MPaulHolmes]

Hello! See page 32. Wait 3 hours to download it, then go to page 32. haha

Page 39 has a picture of it after it's soldered. Page 44 shows where the 2 ground wires poke through the control mounting board, and where they get soldered to the control board. Sorry about some of the pictures. It's green ground wires in some of the pictures, and blue in others. The pictures are a collection of a few controller assemblies, since the process evolved as I went along. Then they magically become yellow ground wires in the next picture down. But it's the same ground wires. They are the ones that get soldered to PH1 and PH2.

The control board doesn't have to be connected, but it can be connected to the power section while testing it. It just makes it a little easier to troubleshoot if the gate resistors aren't all soldered already.

There's hardware current limiting, which is adjustable from about 495amp to 775amp. The software current limit isn't user settable, since Fran thought that would be a good way to blow things up. hehe. It could be made user adjustable though.

[The Toecutter]

Is the adjustable limit for both motor and battery current simultaneously?

I presume that if I use higher voltage MOSFETs(or go to IGBTs), and the necessary components to make them work, there will be no issues using the control board? I want 216V/500A.

I looked at pages 8 and 9 of the updated guide you posted. When I go back there tomorrow, I will check his board to make sure they are in the right order. If we don't solve the error light issue, I will come back with more questions.

what times are appropriate for which to contact you by phone?

[MPaulHolmes]

The overcurrent circuit monitors only motor amps, but battery amps are motor amps times pwm duty.

No higher voltage issues with the control board that I am aware of. The only possible issue I can think of is the separation distance between the power ground and control ground. I don't think that will be a problem though. There's nothing like actually trying it.

Let's see, good phone times are in the afternoon after work. Like after 3 or so. We sometimes are out of the house to Costco to get pizza or something.