Trip to the mainland for Dyno time.
Man oh man. Some times when things get hard they get REALY F-'N HARD!
So I spent tuesday ballancing the cells under the hood and loading all the things I could into the car including 6 spare IGBTs 4 spare driver boards 3 of which are to be sold to a customer. Loaded 4 extra Zero packs for more power if I got that far. Had 10 fuji 800a IGBTs sent directly to the tuning shop (Malone tuning) and they were over nighted from FUJI usa because the clowns down their sent me 10 of the wrong parts tuesday morning... I put my ocsilloscope and soldering iron in the car an everythign else I could think of. Went home and managed to get to bed at 10pm then got up a 4am to catch a 515 ferry....
Made it to Malone tuning at 8 am and plugged in to charge at my limited of 3kw while we got setup. First we went got a coffee (had 2.5-3hr to kill) then we started bolting the flange adapters to the hubs of the car and find the lug nuts my fancy wheels use dont work... So off to lordco then CDN tire to find a set of standard lug nuts. Back again to finish getting setup...
Finaly once we have it all setup on the dyno packs we try doing what is supposed to simulate a inertia run and the dyno tries to match the load of the motor we tried starting at 500 then 750 then 1000 then 4500 rpm before deciding that wont work as every time it created a horible osilation.
They then had to set it up to read HP at different RPM increments and it was set to spend x amount of time at every increment. This worked but scared me so I let off as it was taking for ever for a run to go from 4000-10000 rpm as we had it entered. We then tried one more and at 7400 rpm it triped a over current in the controller the hardware desat tripped and shut the car down. We let things cool but it would not turn on again... So that was rebuild number one.
Before the 2 main runs and tiny bit of fumbling around it was full at 465v... It took just over 2 hr to charge back up at 3kw to get to 465v Meaning we pulled over 6kwh out beating on it trying to dyno it... Which ended up how long it took me to rebuilt it the first time... From there i turned the power down from 750 phase amps to 450 phase amps thinking it should live for sure. I also tried using the inductance and resistance measuring option in the controller to let it try to measure the motor and it give me a number of 150 uH and 25 mOhm (the numbers I have had working for the 1/4 mile runs and the other dyno days are 60 uH and 20 mOhm) so I tried to make a run from 4k-10k with the new settings and it blew up at ~7400 rpm again. But this time we herd/saw a loud bang when it blew up which was the low side contactor exploading and it hit the hood denting it from the bottom then a big plasma ball and smoke come out. Luke Jackson and everyone said they have never seen that before.
So we shut it down and I disconnected the main disconnect in the middle of the pack to make it safer. I then messaged a couple people who I could think of in the vancouver area to see if they had contactors and Casey Mynott came to save the day. So while we waited for him I rebuilt the controller again this time though it was BAD I have never seen a IGBT blow apart like that and trust me I have killed over 100 IGBTs at this point. At first I was really thinking its the way the Dyno packs work. But Luke pointed out the contactor might have bounced and lost contact for a split second. Which is possible as these contactors have been welded many times and freed up with a hammer...
Non the less I got it all working put the old "tune" back into the controller and decided to cut my losses and bolted for the 10:45pm ferry which put me in bed at 2am.... I have to accept the universe doesnt want it to happen that day... Not sure why yet but I will do some more street tuning for now. Its a daily driver and I lay rubber all the time. 7500 rpm is 100kmh and at that speed it doesnt spin the tires with the settings I have been running it at meaning it should not really matter the dyno holding was it there to long.. But I also wondered if it was because there is no inertia meaning the motor could have been slowing or changing speed faster or slower then the controller is used of.
On my way home it run like a top laying rubber at will and passing cars at full power at 100km/h+ so the controller is set well I just know there is more power to be had. Once I get it sorted with the 600a parts I will try the 800a parts again. But I am on a budget as well and need to be cautious. Every time it blows its 2 IGBTs and 1 driver board for sure and thats Min $500 in parts.
The good news is the torque curve is flat with the new inductance/resistance settings so I will try that now that I am at home where its easier to fix.
This is all nothing new to me but I have settings that work amazing on the street and fairly well at the drag strip So I was really astounded that it failed so fast on the dyno.
Pushing forward... As always