1,000 Euro EV Build
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Does he use a 12v starter battery to move at slow speeds? Of course not, uses a Tesla module and cable spark. Love it.
Can't wait for the controller episode, that's where my budget build is currently stuck. I got a $20 donor vehicle, a free forklift motor, free 18650s I've spent 3 months testing one at a time, but I can't find anything cheap for controller and I'm about to settle for electric stoves burners in a water tank for speed control.
Can't wait for the controller episode, that's where my budget build is currently stuck. I got a $20 donor vehicle, a free forklift motor, free 18650s I've spent 3 months testing one at a time, but I can't find anything cheap for controller and I'm about to settle for electric stoves burners in a water tank for speed control.
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I was about to give you a bad time about your crude alignment job between the motor and transmission. But, if this is your idea of a low cost controller, alignment issues are the least of your problems!
However with this sense of adventure and only if it can be done safely, you might be game to be a tester. A lab rat so to speak. What about moving a heavy duty alligator clamp (like on the end of jumper cables) along a TBD diameter section of Nichrome or even steel or stainless steel wire/rod as a crude variable resistor. Maybe start with 2-3mm diameter X 30-40cm long. Be prepared for hot flying pieces of metal. Try it first outside the car with the wheels jack-up, like your first 12V test. VRs this size, rather than a straight rod, are usually a coil around a heat resistant core. With some trepidation, I say use your best judgement.
I've always wondered if this would be way to limp home with a dead controller, at reduced voltage, out in the wild with a brushed motor set-up.
However with this sense of adventure and only if it can be done safely, you might be game to be a tester. A lab rat so to speak. What about moving a heavy duty alligator clamp (like on the end of jumper cables) along a TBD diameter section of Nichrome or even steel or stainless steel wire/rod as a crude variable resistor. Maybe start with 2-3mm diameter X 30-40cm long. Be prepared for hot flying pieces of metal. Try it first outside the car with the wheels jack-up, like your first 12V test. VRs this size, rather than a straight rod, are usually a coil around a heat resistant core. With some trepidation, I say use your best judgement.
I've always wondered if this would be way to limp home with a dead controller, at reduced voltage, out in the wild with a brushed motor set-up.
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I mean, I knew you had plans with some left over IGBTs and whatnot...
But my own plans were to actually attempt a big cluster of liquid-cooled nichrome if I have to.
... Hence me waiting on every word from you about a cheap controller
Nichrome..
Thanks for demonstrating how easy it is to get traction from a DC series motor.
Getting sparks does mean more views, but a controlled way to deliver power is preferred.
Regen won't work, so all you need for a controller is a voltage (throttle) to PWM converter (SOT23, three or four parts), current and temperature feedback (LEM sensor,NTC), a power gate driver ( 1 TO220 device) and a mosfet/schottky power stage.
The driver is the feedback path for torque and speed control.
Thanks for demonstrating how easy it is to get traction from a DC series motor.
Getting sparks does mean more views, but a controlled way to deliver power is preferred.
Regen won't work, so all you need for a controller is a voltage (throttle) to PWM converter (SOT23, three or four parts), current and temperature feedback (LEM sensor,NTC), a power gate driver ( 1 TO220 device) and a mosfet/schottky power stage.
The driver is the feedback path for torque and speed control.
BTW, I think I can do a conversion for less than 200 Euro.
Using the starter motor of my current ICE ride. Add the simple DC series controller et voila.
Won't go faster than about 20km/h, so it's in the category agricultural vehicles up to 25km/h max speed.
Using the starter motor of my current ICE ride. Add the simple DC series controller et voila.
Won't go faster than about 20km/h, so it's in the category agricultural vehicles up to 25km/h max speed.
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Next episode :
https://www.youtube.com/watch?v=bzfdMME4o-Q
https://www.youtube.com/watch?v=bzfdMME4o-Q
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1,797 Posts
I knew this part of the build would be the tricky one for me.
I don't feel like, after watching this, that I know how to find and necessarily build a cheap speed controller. I appreciate that someone else can and did, but can't so much see my own path there.
In any case, can't wait to see the sheepshitmobile roll out
I don't feel like, after watching this, that I know how to find and necessarily build a cheap speed controller. I appreciate that someone else can and did, but can't so much see my own path there.
In any case, can't wait to see the sheepshitmobile roll out
Hi Damien
Just spent a productive couple of days going through your videos on this and the E39 build, thanks for sharing. I very rarely work on electronics over 3.3V these days but I've certainly been inspired to get off my arse and look at some options for my own E39 next time the engine fault light comes on.
If you're ever in NZ then PM me and I'll shout you a couple of beers.
Boz
Just spent a productive couple of days going through your videos on this and the E39 build, thanks for sharing. I very rarely work on electronics over 3.3V these days but I've certainly been inspired to get off my arse and look at some options for my own E39 next time the engine fault light comes on.
If you're ever in NZ then PM me and I'll shout you a couple of beers.
Boz
Im thinking about giving building this controller a go. I there any idots guide to the miller effect somewhere? I'm assuming, maybe incorrectly, that the resistor values need tweaking on a per build basis even if the same IGBTs are used so I'd need to get an oscilloscope.
I've converted a motorcycle with off the shelf parts, but my budget won't stretch to off the shelf for a car.
I've converted a motorcycle with off the shelf parts, but my budget won't stretch to off the shelf for a car.
I've been trying to understand what's going on with the IGBT's instead of just copying it, what I cannot figure out is what the battery + and motor + are not just connected together but are connected to collector 1 on the IGBT(s).
I can see how its switching on and off the connection between battery - and motor - according to the pwm to control the motor speed, I believe this is called low side switching.
I can see how its switching on and off the connection between battery - and motor - according to the pwm to control the motor speed, I believe this is called low side switching.
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