Volkswagen ID.4: Electric Motor Teardown and Analysis

hi everyone and welcome again to monroe uh monroe live um today we've got something that's a little bit different not often does a company ever give us one of their products and and say we can talk about it or take it apart and use it on our show today i'm going to be thanking the guys over at vw who who have let us have a look at the id4 electric motor now this is a this is a permanent magnet motor and i'm going to get into a lot of the details but in essence like i say that's very bold of vw i'm very happy that they let us do it um but we are going to tell the truth on this and that is the rule so there's nothing i'm going to be holding back they're not paying me and i'm definitely not paying them so we're going to go through this in detail in some detail to show you exactly what's going on with this particular strategy so the first thing i got to tell you is that this motor has been pulled apart and there's a short video that you're going to be able to have a look at that shows how all the different parts come from a part this uh this product um is different than most of the other guys the uh the strategy for volkswagen was to look at a a modular design that would allow them to use this motor wherever they want it so they have mounting uh mounting brackets and lugs that that will allow them to then take this motor and stick it into pretty much any uh suspension system that they want to try and uh and adapt this motor to so that's a different strategy than when tesla has where tesla has gone and tesla has put the the mount the motor mounts right inside the casting now this adds more pieces but it gives you a lot more diversity and with volkswagen being as big as they are they've got you know they have they have they're the biggest car company on the planet so with them if they want to try and retrofit something else or they want to use that motor let's say on a pickup truck they don't really need or want something that's going to look like this they want to try and stay with something that's got common mounts that they can mount the the rest of the suspension to so the um uh the strategy that they've got is great um and uh and we're kind of uh interested in looking at what happens when somebody's looking at a global market instead of a dedicated market like tesla is so we're going to be going in and looking at each individual area of this electric motor so that we can bring you the best possible amount of information okay so let's start out with the gearbox normally this is about the first thing that we're going to pull off and as you can see right along here you can see that there's this black stuff that's our tv rtv is used as a sealant here i'm kind of a big fan of our tv and and the reason for that is because you never get a leak path this is uh this is a good idea from the from the standpoint of closing this thing together but let's talk about the overall strategy so the big challenge for the big issue that that they had with the gearbox was they had to make sure that they could make the lightest most cost effective gearbox but they also wanted to make sure that it lasts the life of the vehicle service now i don't know what the vw's lifetime is tesla is shooting for a million miles but i'm not sure whether the rest of the car is going to be able to survive a million miles so at the end of the day we're looking at this product right here and we're seeing things that are different than everybody else alrighty so let's just pull this apart a little bit and have a look at what's going on inside so we're going to look at this shaft right here first this shaft fits into we're going to move over here this staff fits into this part of the electric motor so you've got a dead accurate alignment between the spline that you see in here the female spline and this male spline that you see on the other side now what does that do well that allows volkswagen to go with three bearings instead of four like on most of the regular products so you can see in here that there's one bearing down below normally there'd be another bearing somewhere here and then you'd have these two bearings they're kind of common now the next thing you notice is those bearings are quite small compared to what you get with tesla the tesla bearings are gigantic now this is uh this is one of these things where people make decisions this product is supposed to be for the life of the vehicle what what is their life versus what tesla's life is now tesla's head said in the past that they want to have a million miles that's a that's quite a lot so i'm not sure whether they're counting on the ball bearings to do that or whatever but this is a clever design because they can get rid of one of the one of the the bearings that normally would be in this type of an inch and i don't think i've ever seen one up till now that that has just the three bearings so what does all this stuff do for them well what it does is it reduces the amount of friction any time that you can reuse friction you're going to increase mileage and so from that standpoint this looks like a pretty good idea one of the big problems with reductions of bearings usually has something to do with noise and so to overcome these issues volkswagen did quite a bit of a testing especially when it comes to noise and acoustics they they wanted to make sure that this was going to be as quiet as it could possibly be and that's why there's the very tight tolerances between this shaft right here and the uh the female shaft that's on the uh or the female receptacle that's on the rotor so everything here looks pretty good we were pretty happy and volkswagen was very proud of what they did however um when we were looking at the product we found burrs so let's look under here and you can see that this is a what we would call a plunge cut and um it's fine except on the casting we found these burrs um volkswagen was not happy to hear about that and they're looking into it now this is a pretty good design as far as i'm concerned um it's a it's a cost-effective design for sure i like things like the rtv and and i like i like the fact that they could figure out how to get rid of another bearing this was uh to go to three bearings on a jet engine was a big big deal and um and when it was done a long time ago everybody else copied it i'm sure that everybody's going to be copying this okay let's move on to the cooling strategy now the cooling strategy on here is a little different than everybody else but before i do that let's talk about what materials were used so over here with these two uh these two components here these are high pressure uh die castings and they uh they pop up at 383 or 384 aluminum sometimes our our machine said it was three three a three sometimes it said it was three eight four the center section is a low pressure die casting and it's a three one oh five um that that particular component was looked at by volkswagen and and what they thought was maybe we could go to an extrusion um that extrusion turned out to be too much of an effort or an issue mainly because probably they had a lot of machining that they would have had to do and sometimes an extrusion will come out heavier but at the end of the day this is the way they went it seems to work really well for them and so i'm pretty i'm thinking that this is going to be pretty good for them the the strategy that they came up with where the um and we're going to show you this in a second but in essence the the coolant is going into the inverter this is the inverter and then from the inverter it's going into the motor so the inverter has turned out to be the number one issue that they want to try and cool first which is the right way to do business and then when you take the inverter and i'm not going to do this entirely but if you take the inverter and you pop it in place like so then what happens is these different outlets will connect together and it uh it it makes your it it mates all your different cooling um cooling attributes together so that's kind of like the overall strategy let me move this out of the way so i can get to a little more of the detail so let's look let's look at what we've got when we start we start seeing inside here so if we look inside again we're looking at the rtv that i showed you a second ago we we're looking at how they've sealed this thing off but the circulation i think is a lot more important than uh than than everything else so the coolant is going in through this port right here coming out in this slot and then heading into the low pressure die casting which is also the stator housing and we we we really liked is that as the coolant is flowing it's going through this passage connecting into this one going into that one turning around so it's cooling the whole outside basically with a racetrack or serpentine kind of actuation and then ultimately what happens is the hot coolant is now coming out here and heading back so again the brilliant part of this is they've eliminated an oil pump an oil filter a heat exchanger and and that's something that tesla has on board that these guys don't have they don't have to do it because if we look over here you can see this is the oil filter this is the pump and this is the heat exchanger that that tesla is using that the vw doesn't have so this is a good idea because you're eliminating um you're eliminating a system so in this particular case volkswagen has basically jumped ahead of tesla in uh getting rid of these three components so their objective when they were creating this uh this motor uh and gearbox assembly was to try and figure out how to do a simplified version of of the product and and keep that um keep that uh that cost down they also thought it'd be great if we could figure out how to do the inverter first because really and truly it's everything's about electronics the motor doesn't really care how hot or cold it's going to be it's all about this thing right here now the one thing that we did see that totally blew us away was these little tiny squirt holes so let me get over on this side so if we look right here so this little teeny tiny hole is i think the bleed so the coolant is going in through this port right here it goes all the way around the hole of the housing and then this is the out port which will go to the return line for the heating system for the cooling system so that little bump right there that little hole i believe is a bleed just to make sure that there's no air inside the system okay so let's move on now and i want to talk a little bit about the rotor and the stator the stator is this part right here and the first thing you're going to notice is that this does not look like that okay this is from a tesla and this is using um wire wrapping okay this is a hairpin design and quite frankly i like the hairpin design better because in essence i can get about a 60 fill versus a 46 percent fill over here with um with the the typical windings that you'd see an electric motor those kinds of things kind of tell me uh something else it means basically that i'm probably going to use a different kind of a magnet and that magnet is probably going to have less of something called dysposium in order to in order to make it work and dysposium and neoditium are the two most expensive parts of any magnet so if we have a look at that let's look at right now the the the way the motor is put together and in essence what they're using are four big long bolts this is the bolt right here and in essence you push it through and then you uh you run it down with a nut so our guys like this because it allows you to compress the laminates we'll talk more about laminates in a minute but it allows you to compress the laminates and the um and the magnets and and it allows you to do that at the end and then keep them tight because the laminates the magnets and the spinning all cause a force that wants to basically blow the electric motor to pieces by doing something like this with this long motor or sorry this long bolt you're holding it together and you're doing it in a cost effective way the problem is i don't like bolts i'm going to talk more about that in a little while one of our things is that i talk to our customers all the time about getting rid of threaded fasteners they're the highest and most problem problematic of all the different components you can put in any product so a second ago we were talking and um and the guys the electrical guys were telling me well they liked it and i already told you all the reasons why they liked it and i said all right i don't like the threaded fastener so how can i get around this problem well the way to do that is by using the something that would look like that rod shoving it through and when it comes out the other end you clamp everything up in a fixture and then you do something called radial riveting radial riveting works faster than a threaded fastener and it'll never come out never it's always going to be there whereas threaded fasteners if you looked at some of the other ones i've talked about as soon as they're side loading on these they start to undo and the reason i know that is because when i was at ford i i was in charge of the ceiling and fastening lab we had an engine division and we found that any side loading on a threaded fastener especially with a nut is a real problem so i like the idea of holding it together without any adhesive i don't much care for the idea of of using a threaded fastener and there's a way around it so that's free consulting for vw so let's talk about one other little aspect that we thought was interesting the the shaft uh the the rotor shaft is is not heat treated now this was uh this was a conscientious decision on vw's part because they said that if they put threads on here they would be easier to deform and they didn't like that idea so instead of having a bearing lock nut which is kind of like what everybody else does they put in the four bolts and that saved them from getting that shaft heat treated and i think that that could work that that's a lot of experimentation to make something like that happen so these are these bolts right here um when they're run down they're going to be going through the same process that i talked about before you run them down to torque and then you're going to squeeze it a little bit more which will put a load in this shaft that's going to allow them to to be into a plastic state and that'll hold it together even better so kudos for how they did it i would just do it differently do something here let's just uh pull off the cover plate and talk a little bit about the magnets right here i have the the magnetic array for the for the nissan leaf over here i've got the tesla model 3 and model y and over here we've got the delta arrangement that that volkswagen has decided to go with so you can see this looks a little like that but it's not the same and and quite frankly the one other thing that i thought was kind of interesting was let's have a look at the the green cloth here and this will tell us what um what it looks like like the magnetic array looks like in this vehicle now have a look at this see that pattern right there okay that pattern is done like that to get rid of noise okay noise abatement is a big thing with uh with electric motors if we look at the nissan product you can have a look here and you can see that there's only one only one offset if we look at the tesla you can see that they've got a small one at the beginning and the end and a long one in the center these two will equal that one in the center and that again is done for noise and performance i have never seen this before but you know what i like it because this this gradual offset anybody who's ever gone over a train track in the united states knows that when you hit that train track it go or when you hear the train going over where two uh train rails come together you'll hear the thunk the thunk if you go to any of the high speed trains like the ones in in china or japan or in europe they don't make any noise and the reason for that is because they're cut on a bias so america we cut them this way so they butt together but in europe and in japan and china they cut them on a bias and that bias allows the wheel to go over it more smoothly and that's kind of the same thing that's happening here with the uh with the the green cloth telling us this probably will be give it a little more performance but on top of that it's also going to help it out with noise and noise is a problem with electric motors so let's look down here at the um at the laminates now i've talked about these before we pulled out a couple of lan laminates we pulled out a couple of these things and and you can see here that this is where a magnet goes that's where a magnet goes and this is where a magnet goes so what's all this other stuff well this is called uh skeletonizing and all they're trying to do is get rid of whatever weight they possibly can it's a very good idea there's no reason in the world why they we need that extra that extra weight in order to make the laminates work and do their job so by getting rid of it um we've seen this on pretty much every motor but this is one that's uh that's kind of a done a very good job on skeletonizing so how do we hold this whole system together well right here we have one two three four five six seven eight nine nine threaded fasteners that basically go through this hole through the through the stator housing and into into the the front end of the gearbox okay so now we're gonna wrap this up by talking about the inverter but before i do that there's one thing i i wanna i wanna uh kind of bring the audience up on uh monroe associates we've worked on everything from barbie to the space station as far as designing new product one of the things that we found that changed the minds of people that um that that we work with is what we call the the good design principles card it's this thing right here in it uh on one side we've got some good design principles on the other side we've got some rules and regulations but in essence what we're looking at is we want to design the product so bob can put it together and bob is the blindfolded one-armed builder now why would i want to do that well because a robot is basically a blind one-armed idiot okay it only does one thing it picks something up it puts something down remember that ad where the big yeah kind of like that so a blind one-armed builder if he can put it together a robot can put it together and if the robot can put it together then a man can usually do it faster cheaper and better except for something called the 3ds dirty dangerous and drudgery so that's one aspect the second thing is this right here okay the the part value challenge there's basically just two rules does the part have to move i don't care if it does right now but in a new design could you get rid of that movement does a part have to move or does the part fundamentally have to be a different material okay when you ask those two questions you you wind up with penalty points if you can't say yes and in essence for us the part value challenge is telling us that that part should be either eliminated or combined with other parts another way that we've got to make things happen in a new way is right here these are the poor quality drivers if you look at almost anything that's modern you'll see that it probably snaps together in the olden days they use screws and why did we move to snaps because they're better people say oh no snap fit's not so good that's wrong and i can make anything snap together including wood parts so we can design now what we could never design in the past if we can just figure out how to get rid of fasteners and that threaded fasteners is what everybody usually says but really and truly it could be threaded fasteners it could be rivets anything that's a slave fastener is a problem so these are things that that we would normally do now i've said that i don't like some of the threaded fasteners that that i see on this product i think there's too many of them but let's look at everything that you've seen so far this product has simple vertical or straight down or top down assembly strategy this is great for bob the bob philosophy of being able to put it together with one hand behind your back and your eyes closed that's that's a great idea that's the kind of idea that we really want to have so i want i want to look at a product with that philosophy and when i look at this there's a lot of good things here so we're going to talk about the inverter so let me let me let me just show you the one thing that i kind of like it's hard to really show exactly what's going on so i've removed the the case over on this side so that you can see so i can expose the leads here to the electric motor and if we look at the way the inverter goes i showed you this once already but in essence in essence this is going to go right over the top of these two components down here so you're going to be able to drop the inverter on top it goes through the casing and then i can i can fasten those screws so that's good top down assembly but there's more so we look inside here and we might as well start right on the top um you'll notice that there's a lot of threaded fasteners for this like i said in germany they must be able to get threaded fasteners 10 a penny so so let's take off the the lid and when we flip it over you can see that there's something here this black thing this is an emi seal this basically is keeping any sort of electronic discharge in or out of this box you don't want to have that sort of thing and so we move that over there now i i like the idea that this is all vertically down i like a lot of what i see i mean everything here is vertical i like that that's good the problem is look at all the screws holding it in place uh i don't understand it this has got more threaded fasteners than anybody nobody has as many threaded fasteners as what we've got here so next thing that comes off is the top cooling plate and this is basically a heat sink that wicks away heat from the from all of the components down below here now we've got the um now we've got the next uh layer of the next layer of of componentry and under here you've got the cooling tray these are the pins so the coolant that we talked about that goes through the uh the electric motor comes in here flows around here that goes around these pins these pins then wick away the heat and that means that these igbts here aren't going to get terribly hot so we got this down now one of the things that that we really liked is this doodad right here let me just put this down this this is called a bleed resistor and the bleed resistor fits right here it's glued down so when i take when i take this board and put it over the top of the bleed resistor i only have to make these two connections down below now that's what that's what we have here on the vw this this is what we've got this is what we've got over on the uh on the uh nissan leaf this is a monster size and the leaf is a much smaller capacity electric motor now this is kind of interesting this is not my this is my least favorite this thanks this probably comes in second oops sorry this here's the the tesla here's the this probably comes in second for me this bleed resistor right here which is screwed down this could easily be a snap fit i can i can make snaps either on the plastic or into the aluminum and snap that in place with the glue it'll never come off never and by the way nobody's going to service these things but my favorite still is the bleed resistors that you find on a tesla and and then they have their own little thermal pad that goes over the top of them i like the idea of putting this kind of stuff on the boards because i know that it's going to be right all the time this requires manual assembly or robotic assembly depending on how fast you're making things let's take out the um the cooling tray again i like this uh i like this pro this uh this design because it's vertical down but it's also it's also cleverly done so let's take out the capacitor um sometimes i can get this sometimes i can't here let me do it this way so this is your capacitor and that's basically what makes the electric motor work then you've got a secondary capacitor that comes out and then you've got your bus bar that comes out now have a look at and then over here we have a we have the the connection that we we need to get to the electric motor over here is a is the connector that that comes through and then um basically it's uh it's bolted in place from the back side um when i first saw this i said how come there's no seal but the seal is on the is on the uh on the male connector the female is basically sealed off around this outside edge and around the inside edge so this is a good idea there's a lots of good ideas here that make me think that that vw did a great job my only complaint is holy mackerel i cannot believe how many threaded fasteners i i have never seen this many threaded fasteners on a product this size or this type i i i think that um i think that uh one thing we we should note is that dr deming used to say that with threaded fasteners if you put more of them in your quality is going to drop and the reason for that is because threaded fasteners are that's the wrong name these are called threaded un fasteners they're threaded on fasteners because at the end of world war ii everybody complained about componentry that was on different products from different parts of the world especially britain and and canada and australia where they were using things like acme and whitworth they had a hard time getting the bolts off they were too tight they didn't like that products would break and they had a hard time getting the bolts off well with a 60 degree inclined angle the angle of the thread is at 60 degrees and acme is at 15 which is a locking angle and whitworth it's just as bad eight i think eight degrees or whatever and square threads these things are made to stay together forever we don't use them we use a 60 degree threaded un fastener and that's what it does if it vibrates if it thermal cycles if it gets any side loading it undoes itself now how do i know that because i used to be the co-captain for ceiling and fastening at ford engine division and i can tell you for sure that that we ran a gazillion experiments and threaded fasteners are not your friend get rid of them i highly recommend that if they're going to do something like this there's only one way to hold these things in because these screws are too small to uh to go into yield so i would highly recommend that you glue them uh loctite something like that uh but if it was up to me i would figure out how to sandwich these things snap them in place and done that's it you aren't going to be tearing your car apart to change or fix an inverter i just don't think it's going to happen i think that this is just like your ignition module nobody fixes those either so with all of this what did we what did we find well on the upside there's a lot of good things here a lot of interesting product um they've done a great job on eliminating an oil filter a pump and a and a cooler i like the fact that they've they've gotten to use the uh the coolant as opposed to oil i kept saying oil there's probably going to be a lot of deletes that you're going to wonder what's going on but that's that's one of the things that that's happening there on the downside um i really wish uh uh that uh that i would have saw less less less less fasteners um i i think quite frankly that volkswagen did did a pretty good job so um and just for those folks who want to know we already tested the this is a low pressure die casting and it uses the same material as the housing so at the end of the day this is a very good example of the way a product should be designed i think a couple of exceptions but for the most part i like what i see uh thank you volkswagen again for for allowing us to film your uh your powertrain um and uh i'm not sure if they want this back but you can have it back but i don't think it's gonna work anymore so anyway until next time thank you again for watching monroe live and keep tipping those cashiers thank you and have a good night [Music] you

Channel: Munro Live

Views: 975,560

Keywords: EV, BEV, Sandy Munro, Munro, Electric Vehicle, Benchmarking, Electric, Insight, Lean Design, Design, Comparison, MunroLive, MunroLive.com, ElectricCars, Volkswagen, Voltswagen, ID.4, ID4, VW, VW ID.4, VW ID4, Review, Car Review, 2021 VW ID4, 2021, Automotive, Automotive Review, Motor, Electric Motor, PM Motor, Car, Teardown

Id: 3Bab6CttkEY

Length: 34min 54sec (2094 seconds)

Published: Mon Jun 07 2021

Reddit Comments

[u/akagordan]

He has a lot of complaints about the amount of fasteners, but maybe doesn’t know that VW has some absolutely insane vibration requirements. I’m an ME working on a next gen inverter for them and it’s tough.

Cool video though.

[u/TadaoBaba]

Super cool.

[u/frank_h1994]

Really cool to see. Liked the comparison a lot!