openinverter forum

Hi Everyone, If you have used Ver2 kit with an Enova Motor, can you please tell me what current I can expect during test start-up, using 36v (3x 12v batteries) on bus? I have connected the motor so that I can do an initial test run and protected with 30A fuse - it blows straight away on start. I'm a bit wary about increasing further as I don't want to bust anything.
Any advice is welcome...... Steve

Hi Steve. Post your parameters so we can see if its those Peter

Hi Peter, thanks for your quick reply. I'm using the basic parameters in the firmware and following the instruction sheet. Is that what you need ? I'm still in the test stage with my kit, but once the driver cards were connected, I seemed to have a pretty good sine wave on each IGBT output.
Thanks.... Steve

Hi Steve. Yes the basic settings. Boost, Fweak, Fmin, Fmax, Ampnom, throttle min, max, etc. I have the Enova motor but using the CombiV8 control and Enova power stage. Maybe I can help by setting mine up same and see what happens. Peter

Hi Peter, the parameters are as loaded with mods to fweak, ampnom and fslipspnt as per the instruction sheet. I've done everything to the letter and, as far as I can see, it should run at 10Hz. Thank you for you offer to set yours up. That's really good of you. I'll need to find the figures from the list first.
Many thanks ... Steve

Hi Peter, I've found the parameters listed as follows-

boost 1700, fweak 90, fmin 1, fmax 200, ampnom 0, fslipspnt 0. (for test, ampnom 100, fslipspnt 10, fweak 10 )

I hope this helps. Cheers.... Steve

Hi Steve. I would suggest lowering ampnom to 5 and raising fslipspnt and fweak to 100 and slowly raise throttle watching dc current. Where are you based ?

Thanks Peter, I'll give that a go and post results. We've been in contact before. - a while ago. I'm located not far from Rugby, near J18 M1. I will be travelling to your neck of the woods sometime soon to visit my daughter and granddaughter in Sale - now that we're allowed out
Will be in touch soon .... Steve

Hi, this is an update to previous posts - before trying out Peter's advice, I decided to do some (more) checks.
I appears that I have voltage on the bus ( and caps). Running the inverter (start 2 etc..) I have waveforms - the same on all IGBTs.... but I also have approx 3.8 volts across the bus connections - no batteries connected. I'm not sure where this voltage is coming from.... Any ideas ? I thought it might be the deadtime so I increased it from 63 to 150 - it made no difference.
Any thoughts are more than welcome.
Thanks..... Steve

Hi Steve. Try using 24v on the bus with a series resistance (to limit current) and use 3x 12v lamps connected in wye formation on the phase outputs just to see if switching a load and varying throttle shows the system is working.

Thanks Peter, I will try that. As I am not that far along in the test sequence, my throttle is not yet hooked up, but I will do it and see what happens.
Any thoughts on voltage on bus ? duff IGBT leaking ?? That's the only thing connected to the bus with any voltage in it (except for the voltage sensor which I disconnected to see). When inverter halted you can see the caps discharging on the voltmeter.

We be in touch..... Thanks again ...... Steve

Hi again everyone, It seems that I had more than one problem with this - and many thanks to all who offered advice.
The first thing - I bought a new scope - one that gives me proper waveforms. Then I found there was no output from one opto-isolator.
I replaced that and it works (but I messed up a couple of solder pads doing it. I'll need to replace the board for the final job).
I now get 6 lots of square waves from the driver boards..... but.... there's no dead time between the top and bottom outputs - even though I set "deadtime" to various values up to 200. I get the same sort of wave from the Igbt bus even with no voltage applied. Applying 12v to the bus, I get stable outputs on the phases (still no deadtime apparent on scope). I'm obviously doing something wrong here. I've posted some screen shots of traces. Comments please. Thanks....Steve

A). from driver output,
download/file.php?mode=view&id=9255

and B) from phase output using 12v bus.
download/file.php?mode=view&id=9253

The bottom output should be inverted to the top output. I don't think you're scoping right. Also at that time base it will be hard to see dead time.

Hi johu, thanks for your quick response. I'm still learning how to use this scope, so bear with me. Maybe I need to trigger differently?
I'll check a different timebase to give a better view. Thanks for your advice ..... Steve

Hi johu, I've looked again at the traces for the driver boards. Traces are similar for each board and this is what I get -
1st. 2 pics Driver Board Input at 5uS and 10uS both 2v/div.
2nd. 2 pics Driver Board Output Top/Bot Gate.
From what you say, this is what I should have. I think I see deadtime in operation here.
Thanks again for your advice - now more testing..... Steve

Hi Everyone, Just an update on this saga - Today, tested inverter output with bulbs, as Peter suggested - Lights worked !. Connected Enova motor and that worked too (10Hz) . Problem must have been the defective Opto-driver ic on Gtop on C driver board.
Next job .... order batteries.
Thanks to everyone who gave advice, it was much appreciated...... Steve