Tesla Model 3 Torn Down, Hacked and Set On a Dynamometer, Exposing Unusual Tech Details (electrek.co)

Rei writes: With an estimated 8,670 Model 3s delivered, a race is on as competitors and owners work to figure out its limits and explore the tech behind it. Many-time Tesla teardown expert "Ingineerix" has posted a series of videos and discussed his findings on Reddit. Among them: what appears to be the industry's first switched reluctance motor, a massive "smuggling compartment" allocated for a future front-wheel motor, no physical fuses (all solid-state), significant wiring harness length reductions via the use of multiple body controllers, a swappable crash energy absorption system, a liquid-cooled compute unit, and redundant controllers for all safety-related systems. He followed up by posting a screenshot of the car tricked into "factory mode" to reveal its internal specs, including a 1200A max discharge current, 370kW max discharge power, and a 76 kWh pack with 72,5kWh usable. Meanwhile, Munro and Associates tore down a Model 3 for an undisclosed, "not Tesla" client, releasing a video criticizing its build quality and for difficulty in accessing the HV cables in the event of an accident (Munroe's claims were dismissed by Ingineerix). Meanwhile, engineers from German automakers were extremely impressed by what they found during their teardown -- particularly the power electronics system, which they described as "compact, expandable, fully integrated, modular, easily accessible, well-protected, reasonably priced and astonishingly clever in many details." Other owners have been putting their cars on dynamometers to measure their power. Drag Times suffered some skid and measured a conflicting 281 / 327.6 hp with 552 lb-ft torque. Contrarily, Tesla Repair Channel found consistent readings around 250hp when starting from 30mph, but consistently around 390 hp when starting from 10mph. The reason for the discrepancy is not yet clear.

Comments

Re, the motor:

[Rei]

To expand a bit on the motor: it should be clarified that it's not a normal switched reluctance motor (SRM), but rather a PMSRM (permanent magnet switched reluctance motor).

Reluctance is used to some extent in many hybrid EV motors, in the form of "IPM" - interior permanent magnet motors. These are a hybrid of a conventional surface permanent magnet motor (SPM) and a SRM, allowing for high power at high speeds that SPMs don't allow for, as well as reducing magnet sizes (and thus rare earth consumption). By contrast, a PMSRM is a SPM that incorporates permanent magnets into the stator; they don't move and are readily cooled, while sculpting and enhancing the field to increase torque density and help control torque ripple.

It's a new type of motor, combining extreme efficiency, high torque density, and reliability over that offered by an IPM. Getting a PMSRM to work smoothly is an impressive job.

Re:Re, the motor:

[psmoot]

Reality check: if you are living in a 220k home you ARE part of the 1% in the world.

If you earn $32,000 (or 30,000 euros or 2 million rupees), you're in the global 1%. I think that puts you at something like the 80% percentile in the US. The US is very, very rich, globally speaking. What's your point?

I just checked some home stats. The median new US house in 2015 was something like 2,400 square feet (about 220 square meters). I didn't find data on existing houses. The median price for all houses was $188,000 so a $220,000 house is above average but not outrageously so. (I think that buys a 500 square foot studio condo in SF Bay Area, where I live. I really gotta move.)

Re:But I read it lacks basic quality elsewhere

[Rei]

But from what I have read from owners

You clearly haven't been hanging out on the Model 3 Owners Club. It's amazing the disconnect between how certain individuals seems to want to portray it, and how non-selection-biased random owners describe their vehicles. Or, for that matter, photograph them. I watch person after person get their invite, pick up their car, and then rave at how amazing it is... then I check out the latest article to show up about the Model 3 on Google News where they act like everyone's car is held together by gaffer tape and they're furious.

To put it another way: "I just picked up my new (insert-topic-of-interest) and it was perfect!" doesn't go viral in the same way that "I just picked up my new (insert-topic-of-interest) and there was something wrong with it!". Seriously, for example, the rash of coverage over the person who had a dead 12V battery. Literally the only dead 12V battery that's ever been reported in a Model 3, and there were dozens of articles written about it - despite the fact that Tesla sent a guy to his house to take care of his battery for him.

Or more directly: check out some of the teardown videos linked in TFA. Does any of that look like poor build quality to you? One thing that's neat is you'll notice blue markings on a number of the bolts; that's common in the aerospace industry, but rarely in the automotive industry. Those are witness marks. They're used to double check that bolts were tightened to the proper tightness.

That's not to say that there haven't been some issues. Things that actually have been problems, at least over certain points in time:

  * There used to be frequently a small sag in the hood, going a several millimeters out of alignment with the sides at its middle. It's been fixed in recent vehicles.

  * While handling has gotten extensive praise, some people who don't like a stiff "sports suspension" feel have been complaining about that. Tesla is reportedly working to soften the suspension some.

  * Noise, while quiet by ICE standards, is relatively high by EV standards. Namely, road noise (connected to the aforementioned stiff suspension) and wind noise (worse than the S). But both have been reducing with recent VINs.

  * There's some issues that relate to preference. Some people don't like the Aston Martin-style door handles, while others aren't bothered by them. Some people think the door and frunk hood needs to be shut too hard, while others prefer the solid feel. Etc. So whether they're "defects" depends on your personal preference.

There are some GUI issues as well, but they decrease with each over-the-air update, as well as getting new features. At the top of the most-requested features list that hasn't been implemented yet is moving cruise control speed from the GUI to the right steering wheel control (akin to volume control and station selection are on the left steering wheel control). There have also been a couple issues related to it not remembering various types of infotainment / preference settings between drives; most (but not all) of these issues have since been patched.

Probably a couple other things I'm forgetting.

Re:Nurburgring fiasco.

[Rei]

Regrettably they can't, because the system shuts down due to overheat.

Completely different powertrain. The AC induction motor couldn't handle max power for more than a couple minutes because the rotor would overheat from induction currents. There's no induction currents in a PMSRM. Heating is in the stator, which is trivially cooled.

but what about towing a two-axle mobile stable with two horses in it, steep uphill?

Meh, even Tesla's current induction motor fleet does that sort of stuff just fine. Watch Björn Nýland's videos, he tows huge things through mountains all the time.

Your post is well appreciated (I don't know why you were marked down to -1, that's unfair), but it's premised on obsolete technology. Motor technology is advancing fast, and Tesla has invested a huge amount of money into it.