[DRIVING] BMW Touring + phev motor & inverter

[0tik]

, but consensus on here seemed to be Prius motor alone would be under-powered. I wasn't sorry about that, as it is huge and weighs a ton.

Can you elaborate on that please? I wanted to try this but theres not much info on that. Wiki says mg1 and mg2 are rated for 45kw. That gives 90kw. Should be comparable to outlander rear motor.

[Romale]

Wiki says mg1 and mg2 are rated for 45kw. That gives 90kw. Should be comparable to outlander rear motor.

That's not so. The prius has mg1 = 18 kW, mg2 = 50 kW.

[FFMan]

Can you elaborate on that please? I wanted to try this but theres not much info on that. Wiki says mg1 and mg2 are rated for 45kw. That gives 90kw. Should be comparable to outlander rear motor.

i can't remember all the detail, you could read my project post, i think its discussed in there. Also at the time the dual drive of mg1 and mg2 was i think untested and when i saw the outlander motor it looked easier, neater and a lot lighter.

[0tik]

That's not so. The prius has mg1 = 18 kW, mg2 = 50 kW.

I mean there are no posts from people actually benchmarking it.

[FFMan]

I mean there are no posts from people actually benchmarking it.

i think was my issue at the time, it was was (and maybe still is) something of an unknown as a solution running both motors etc.

However if you are going down this route i have a pair of Prius inverters going for a song...

[FFMan]

at last i found the issue with the DCDC not working. When i removed the gearbox and motor from underneath a while back, i managed to miss out the ground cable to the charger when putting it all back together as i was working blind on parts of it. No wonder the charger didn't want to charge the 12v battery but was fine with charging the main batteries.

All fixed - back on the road, bar a few outstanding issues, and must reinstate and troubleshoot the cabin heating tomorrow.

Ramping down of the regen as the car slows work really well, I have different regen levels for each gear, but next i want a short ramp up on application of pedal just to smooth out the small jolt on initial application.

[FFMan]

All running ok, but i failed to get heater working properly at the weekend. Some water flow issue, so took all the pipe work out and will redesign the flow path this weekend.

Heater ramps up nicely but i think shuts down to protect itself after a minute or two.

I have a BMW bleed tap in the loop which helps but getting the air out i think is the issue to be cracked.

[arber333]

Heater ramps up nicely but i think shuts down to protect itself after a minute or two.

See here maybe it can help you some
viewtopic.php?p=65916#p65916

Also very important is clean 0x285 message. While at first i used several functions with 0x285 within. It didnt work well even when timer was set at 10ms. Then i created a separate hardware timer that is repeating 0x285 at 10ms without any distraction. Now heater works full power without interruption.
Code is for teensy 4.1 but you simply research how to condition a function to a HWtimer trigger.
BMS_status is a value to signify the mode car is in at the time

Code: Select all

// innitialize Timer for BMS heartbeat
IntervalTimer BMStimer;

//setup function
 BMStimer.begin(bmsComms, 10000);
 
 // function for 0x285
 void bmsComms()
{
    msg.id = 0x285;
    msg.len = 8;
    msg.buf[0] = 0x00;
    msg.buf[1] = 0x00;
    if (BMS_Status == 3) // charging
      {
    msg.buf[2] = 0xB6;
      }
    else if (BMS_Status == 5) //error state
      {
    msg.buf[2] = 0x00;
      }
    else 
      {
    msg.buf[2] = 0x14; // detup for drive
      }      
    msg.buf[3] = 0x39;
    msg.buf[4] = 0x91;
    msg.buf[5] = 0xFE;
    msg.buf[6] = 0x0E;
    msg.buf[7] = 0x10;
    Can2.write(msg);
}

[FFMan]

thanks for that. I'll ensure i get some decent water flow and then see how it behaves. At the moment i get no warm air so pretty sure its a circ problem. I had some right angle pipes in from when i had the prius inverter. The Outlander inverter is a different shape and clears a bit of obstruction from the matrix entry points which means i can ditch the right angles.

Fingers crossed.

[FFMan]

So i'm just about to declare this finished. The heating is working though could improve a bit, and today I fixed the charge leds on the type 2 socket, and took out the leds from the dash that i'd been unable to extinguish in code. Only one warning light remains but it has a purpose as a handbrake reminder so i'll try and turn it off in code with a bit more work.

Beginning to wonder if the E46 is harder than a later e90. My son just bought an e90 dash to hook up to the computer driving sim, and it appears to be all can, none of the k-bus and half analogue stuff of the 46. Watching the bigpie BMW with interest as it might be my next conversion.

[arber333]

So i'm just about to declare this finished.

Photos!!!

[FFMan]

Photos to follow soon.

Just a quick update, at the weekend i tapped into the cabin fan wiring so via a relay i can power it using pwn externally. This means i can fire-up the heater on a timer or remotely. In theory if the charger has been set to maintain a voltage, that will then kick in so i don't deplete the batteries with the pre-heating. Will test that over the next few days.

Only 5 packs of the front 6 are reporting in. Seems like a recurring issue, suspect a poor connection somewhere even though the oem connectors locate really well. Will need to investigate but the front pack has to come out which is a pain but doable in an hour.

Next planned is a ramp in to regen, say over 1 sec to reduce the jolt at high regen levels. Also thinking of a 2 stage regen, the first stage at the moment is triggered by an extra brake light switch and activates on the free play of the pedal. I am thinking if the driver presses harder to activate the mechanical brakes this could induce a higher level of regen as well as the brakes. I am thinking regen reclaims a reasonable amount as driving round my way is often accelerate to 50, then come to a stop and lights or roundabout.

[FFMan]

Short update on this project. The front pack BMS has a few issues. One module is lying about the value of a couple of cells, and pretty sure another module is overstating the voltage a tad as i manually checked and balanced them all. Have been looking at DIYBMS as an alternative as BMW modules are hard to come by.

In other news, the original coupler stripped. I knew it was wearing after the last gearbox removal, so prepped the replacement thinking it would be a job for the easter break. It didn't last that long. Let the wife down a mile from home, got towed back by a mate. Hoping the new couple will be a bit more forgiving, plus the latest VCU ramps up and down the regen more sympathetically, so it kinder on the drive train.

I'm guessing there must be some mis-alignment though got to say it isn't obvious.

I think MK3 coupler will be a star based coupler.

[Ev8]

Wow has that stripped the output shaft on the motor?

[FFMan]

Wow has that stripped the output shaft on the motor?

yep - in about 2k miles

[Ev8]

Wow any sign it was doing this was it noisy from the start? Makes me wonder what mine is doing 3k plus miles later

[FFMan]

no noise from the start, but it was a bit clunky as i didn't have the regen ramp up and down sorted.

according to my local gearbox guy, solid couplers can have issues, and on Land Rovers, the coupling has a life of about 50k miles

[FFMan]

Repurposed the rev counter to be eco gauge, an idea shamelessly copied from my mates Mercedes Evan.

Rev counter seemed a bit pointless and this works nicely.

[FFMan]

Touch wood but it is running well.

Managed to sort out the front BMS and balance the pack, and the new coupler is doing its thing. It's a daily driver for me or the wife as an overnight charge is 3p/mile - well happy at the moment.