Go Back   EcoModder Forum > EcoModding > Fossil Fuel Free
Register Now
 Register Now
 

Reply  Post New Thread
 
Submit Tools LinkBack Thread Tools
Old 01-21-2017, 11:13 AM   #3011 (permalink)
EcoModding Lurker
 
Join Date: Oct 2016
Location: INDIA
Posts: 11
Thanks: 26
Thanked 0 Times in 0 Posts
Quote:
Originally Posted by motorulf View Post



Yeah, i am only using 25 volts right now, is that too low?
You are using 25v as HV and running a 208Vac 3PH motor? What kind of batteries are you using?

  Reply With Quote
Alt Today
Popular topics

Other popular topics in this forum...

   
Old 01-21-2017, 03:27 PM   #3012 (permalink)
PaulH
 
MPaulHolmes's Avatar
 
Join Date: Feb 2008
Location: Maricopa, AZ (sort of. Actually outside of town)
Posts: 3,832

Michael's Electric Beetle - '71 Volkswagen Superbeetle 500000
Thanks: 1,368
Thanked 1,202 Times in 765 Posts
Looking at the code, I think the current command of Id = 300 (normalized value) and Iq = 300 might not be enough to get your motor turning. I used that value on my smaller motor and it worked OK, but I think you might need to change yours to 500 or 600 or 1000 or whatever. It's in RunRotorTest(). I probably should change that to an actual current rather than the normalized so it would work with all motor sizes.
__________________
kits and boards
  Reply With Quote
The Following User Says Thank You to MPaulHolmes For This Useful Post:
motorulf (01-21-2017)
Old 01-21-2017, 03:48 PM   #3013 (permalink)
EcoModding Lurker
 
motorulf's Avatar
 
Join Date: Dec 2016
Location: northern sweden
Posts: 33
Thanks: 17
Thanked 20 Times in 17 Posts
OK, here are the DIFF-files for my reverse function hack.
I used source code from Jan-06-2017.
Paul, may i attach that version of source code here?

Diff.zip

It uses the ICSP header for input and the LED output as an indicator.
No settings for reverse-amps, so you get full power backwards.
Use this at your own risk!!




I forgot to add the resistance...
Put resistor values as suggested here, it worked good for me:
Quote:
Originally Posted by thingstodo View Post
I would add a couple of resistors on the board, and one in series with the switch, to limit the max current into the micro.

Perhaps a 22K from Vcc (whether that is 5V or 3.3V) or your top trace on the board to the PIC pin or middle trace on the board. A 10K resistor from the PIC pin, or middle trace on your board, to Gnd, the bottom trace on your board. This one is shown as 'some resistor. That sets up a voltage divider for about 1/3 of Vcc on the input pin, which should read as 0 or OFF.

The switch would go in series with a 2K2 resistor - top trace to your switch .. green wire ... which is now wired in parallel with the 22K resistor. That sets up the PIC pin for about 85% of Vcc and should read as 1 or ON.

These resistor values are ones that I typically use. They limit current under 3 mA and are easy to buy. I didn't look up the specs on the PIC, but I don't expect any issues with low current into the PIC pin.
This was a comment to this:

Making it:

Last edited by motorulf; 01-21-2017 at 03:56 PM.. Reason: adding more stuff
  Reply With Quote
The Following 2 Users Say Thank You to motorulf For This Useful Post:
kalidasbala (01-22-2017), MPaulHolmes (01-21-2017)
Old 01-21-2017, 04:08 PM   #3014 (permalink)
EcoModding Lurker
 
motorulf's Avatar
 
Join Date: Dec 2016
Location: northern sweden
Posts: 33
Thanks: 17
Thanked 20 Times in 17 Posts
Quote:
Originally Posted by kalidasbala View Post
Btw, is there a formula to calculate the precharge resistor value? Also can I use an automotive relay (12v).
The precharge resistor value is a function of capacitance, time and voltage.
I dont have a formula though. Or... i found this
Use a relay that can handle the voltage. I dont think a 12v relay will do the job

Quote:
Originally Posted by kalidasbala View Post
You are using 25v as HV and running a 208Vac 3PH motor? What kind of batteries are you using?
I was using a:

Then i used 3 in series, making it 75 volts.
I use them only for testing, for my convenience...

Last edited by motorulf; 01-21-2017 at 04:14 PM..
  Reply With Quote
The Following 2 Users Say Thank You to motorulf For This Useful Post:
kalidasbala (01-22-2017), MPaulHolmes (01-21-2017)
Old 01-21-2017, 04:18 PM   #3015 (permalink)
PaulH
 
MPaulHolmes's Avatar
 
Join Date: Feb 2008
Location: Maricopa, AZ (sort of. Actually outside of town)
Posts: 3,832

Michael's Electric Beetle - '71 Volkswagen Superbeetle 500000
Thanks: 1,368
Thanked 1,202 Times in 765 Posts
oh yes! precharge resistor/capacitance/time. You need to figure out the RC time constant for your setup. Like this:

Let's say you are using 1000uF of bus capacitance, and you are using a precharge resistor that is 500 Ohms (just random values). Also, let's say you are using 400v for your battery bank.
Things to consider:

1. The precharge relay will have to be able to make 400v/500Ohm = 0.8 amps.

2. The time you need to wait is 5*R*C seconds. So,
5*500Ohm * 0.001Farad = 2.5 seconds. (0.001 Farad = 1000 microfarad)

3. The energy that your precharge resistor must be rated for is:
Energy = 0.5 * C * V * V = 0.5 * 0.001Farad * 400v * 400v = 80 Joules

That's a lot of energy for a resistor. You need a pulse handling resistor like the king of surge resistors, the Ohmite pulsEater (I love that name!):
http://www.mouser.com/ProductDetail/...0Td1E32eWcg%3d

That can handle way more than 80 Joules, so it would be very safe. If a resistor doesn't list its pulse rating in Joules, I would say you should probably not use it.
__________________
kits and boards
  Reply With Quote
The Following 2 Users Say Thank You to MPaulHolmes For This Useful Post:
kalidasbala (01-22-2017), motorulf (01-21-2017)
Old 01-22-2017, 03:27 PM   #3016 (permalink)
EcoModding Lurker
 
Join Date: Jul 2011
Location: Slovenia
Posts: 70
Thanks: 0
Thanked 20 Times in 13 Posts
Paul, I have such trouble with my original inverter on my day to day car that i am thinking of putting your inverter in my car. Just until i prepare everything for leaf motor to work.
Since your inverter clearly works with ACIM motors, would ordinary optical encoder (like computer mouse) work with your inverter for ACIM? I have 60 holes single pulse optical encoder allready on my car.
Encoder is this HC-020K Double Speed Measuring Module With Speed Encoder Kit | eBay
It is powered by 5V and signal is open collector pulse. Would it work with only channel A?

You can see it made here
https://mazdamx3ev.wordpress.com/201...nkoder-senzor/

tnx

A
  Reply With Quote
Old 01-23-2017, 11:33 AM   #3017 (permalink)
Master EcoModder
 
Join Date: Sep 2010
Location: Saskatoon, canada
Posts: 1,488

Ford Prefect - '18 Ford F150 XLT XTR

Tess - '22 Tesla Y LR
Thanks: 749
Thanked 565 Times in 447 Posts
Quote:
Originally Posted by arber333 View Post
I have 60 holes single pulse optical encoder allready on my car.
Encoder is this HC-020K Double Speed Measuring Module With Speed Encoder Kit | eBay
It is powered by 5V and signal is open collector pulse. Would it work with only channel A?
I have a small bit of information for this:

Open collector works fine - the pull-up resistor needs to be sized to allow the voltage to rise to 4.5V before it is 'pulled down' by the open collector. That's my experience using a 24V encoder, separately powered from the inverter. My other motor has a 64 ppr encoder so 60 pulses per revolution should be OK.

I lost a wire, either A or B channel, while the motor was operating and the inverter got quite confused. It ended up stopping but the deceleration was not smooth.

If you only have one channel, the inverter will not be able to tell which direction the motor is turning. I think Paul is paying attention to that now, for the regenerative braking. But it may not be a big change to disable the direction monitoring?
__________________
In THEORY there is no difference between Theory and Practice
In PRACTICE there IS!
  Reply With Quote
The Following User Says Thank You to thingstodo For This Useful Post:
MPaulHolmes (01-23-2017)
Old 01-23-2017, 11:44 AM   #3018 (permalink)
PaulH
 
MPaulHolmes's Avatar
 
Join Date: Feb 2008
Location: Maricopa, AZ (sort of. Actually outside of town)
Posts: 3,832

Michael's Electric Beetle - '71 Volkswagen Superbeetle 500000
Thanks: 1,368
Thanked 1,202 Times in 765 Posts
The quadrature encoder interface requires A and B. I had done a virtual high resolution encoder using a single pulse from a tesla using the change notification pin, but Tesla's resolution is only like 36 ticks I think. The problem with 60 might be the high frequency that the change notification interrupt gets called as the motor frequency gets high. I'll have to look at that and see if it's practical.
__________________
kits and boards
  Reply With Quote
Old 01-23-2017, 12:32 PM   #3019 (permalink)
EcoModding Lurker
 
Join Date: Jul 2011
Location: Slovenia
Posts: 70
Thanks: 0
Thanked 20 Times in 13 Posts
Quote:
Originally Posted by MPaulHolmes View Post
The quadrature encoder interface requires A and B. I had done a virtual high resolution encoder using a single pulse from a tesla using the change notification pin, but Tesla's resolution is only like 36 ticks I think. The problem with 60 might be the high frequency that the change notification interrupt gets called as the motor frequency gets high. I'll have to look at that and see if it's practical.
I am speaking of ACIM motor.
You could make direction of rotation fixed. Like CW determines forward and CCW is reverse. Then if we need to install motor the wrong way we just swap phase wires, motor wont know the difference. That way we could use only signal A. Maybe you could make a menu in code so we can select encoder no. 4 as 1ch encoder?

A
  Reply With Quote
Old 01-23-2017, 12:48 PM   #3020 (permalink)
PaulH
 
MPaulHolmes's Avatar
 
Join Date: Feb 2008
Location: Maricopa, AZ (sort of. Actually outside of town)
Posts: 3,832

Michael's Electric Beetle - '71 Volkswagen Superbeetle 500000
Thanks: 1,368
Thanked 1,202 Times in 765 Posts
The software changes for getting the change notification pin to generate a virtual high resolution encoder are fairly significant, so it might mean having a separate file for that.

__________________
kits and boards
  Reply With Quote
Reply  Post New Thread


Thread Tools


Similar Threads
Thread Thread Starter Forum Replies Last Post
Paul & Sabrina's cheap DIY 144v motor controller MPaulHolmes Open ReVolt: open source DC motor controller 7381 08-02-2023 10:55 PM
Paul & Sabrina's Cheap EV Conversion MPaulHolmes Fossil Fuel Free 542 11-12-2016 09:09 PM
Contest! Name Paul & Sabrina's controller MetroMPG Forum News & Feedback 120 10-22-2011 01:59 PM



Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Content Relevant URLs by vBSEO 3.5.2
All content copyright EcoModder.com