openinverter forum

Hi Friends, I'm "working" on swapping Leaf Gen2 (2013) motor/inverter into an NB Miata (1999). I gave myself a year, and am about 4 months in. I bought the Leaf Gen2 Community Edition, think I have it assembled and installed properly, but am having UDC issues similar to @E46driver here. Here's what I've done so far:

• Had a pro tie CAN slew rate pin to ground with 10k
• Installed latest firmware
• Wired a testbox, with 4 on/off toggles (ON, brake, tbd1, tbd2), 1 momentary button (start), 1 3-way rocker (fwd, off, rev), dial potentiometer, 12v-5v buck converter
• Wired/Pinned a connector for the inverter (less brake out and BMS in), currently have 12v, 5v, ground, start, fwd, rev, brake wired to testbox
• Identified +/- control wires for Leaf contactor assembly (B-, pre+, B+)

Before I went further, I wanted to calibrate UDC. But right now, I can't get past the first udcofs calibration. Schematics and Instructions and Issac96 both lay out same steps:

Code: Select all

set udcgain 1
set udcofs 0

Now make sure the input to the sensor board is disconnected. Get the value of udc and write it to udcofs:

Code: Select all

get udc
500.00
set udcofs 500

E46driver ended up with offset of 299. I feel I have a similar problem as his initial offset was 3842 and mine is 4092! Both extremely high, barely within range, and probably wrong!

E46driver found some bad connections at the headers, so I have gone back and verified all the pins at the connector, double checking gnd, 12v, and 5v feeds. I've gone back to the Leaf and mini boards, and checked conductivity of header pins from front to back, and to adjacent pins. I'm very confident in the mini board as I had those cleaned up by the pro who installed the 10k resistor for CAN. The Leaf adapter board I am mostly confident in. Connectivity was good front to back (is there a better way to check?) and all pins were isolated except 2. These were the right two pins on the left connector (I can't find a board map, not sure how to identify it.)

I followed @Johu's suggestion to @Renegate2020 and triple checked the pin running to R2 and R5. It seems fine, but I didn't follow the other suggestions as I'm not comfortable with the micro-soldering. I could try to check voltage at that pin, but I don't know what it would mean or how to fix if it was an issue.

I appreciate any insight in something additional to check, I'm just not sure where to go. I'd like to get this right before connecting HV (plan to test and calibrate at about 70V). Any help would be most appreciated! Thank you!

Unfortunately I have nothing to add to the linked thread. Nissans voltage PWM is either not working or lost somewhere on the way. If you have a scope try finding the signal right on Nissans gate drive board and then follow it towards the main board.

johu wrote: ↑Sun Nov 13, 2022 9:47 am Unfortunately I have nothing to add to the linked thread. Nissans voltage PWM is either not working or lost somewhere on the way. If you have a scope try finding the signal right on Nissans gate drive board and then follow it towards the main board.

Thanks Johu. I don't have a scope, but I'll see what I can do. I assume signal correlates with voltage, and 0%=0V. Which means I'll need some voltage to trace out the signal..?

It is PWM, fixed frequency around 500 Hz and it has an offset , so it's a few % duty cycle even at 0V

... hence "udcofs"...

Went and double checked my very amateur soldering, and looks like I missed a short on on the UDC feed. UDC is measuring 297, feel like I'm back on track, just embarrased.... more to follow as I continue my wiring and calibrations

Thanks for letting us know anyway

oh man, I hate to revive this thread but... UDC is not picking up voltage anymore. I had this working, but had moved on to other things waiting for some parts to arrive. Five months later, I'm not sure what happened. The nice UDC plot showing the capacitors discharging is gone; UDC now looks like a sine wave. I haven't opened up the inverter again to look, because I don't know what I'm looking for. I've tried to go back to what I think was the original parameter load, and just started over with calibrating UDC. I must have tweaked something somewhere...

What can I provide the forum to help describe what's going on? I'll start with parameter file that I thought was good.

ok, now I've lost the WiFi link... and 5V out the plug is only 2.3V... might have a 5V issues, probably due to my poor soldering skills. I've been practicing, have some better tools, think I'll open things up and take some readings from the actual board.