Smart Roadster (with Prius Gen3 Inverter and Outlander Rear Motor)

Tell us about the project you do with the open inverter
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Re: Smart Roadster

Post by Pete9008 »

Just checked and according to the Oak Ridge report the Gen3 Inverter normally works with bus voltages of up to 650V!

Must admit I do feel a little hesitant about going to higher voltages, just can't think of any good reason why so keen to hear all views?
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Re: Smart Roadster

Post by arber333 »

Pete9008 wrote: Wed May 11, 2022 4:24 pm
arber333 wrote: Wed May 11, 2022 4:13 pm I would not advise to go over 104S. I did and i am at the end of my inverter comfort zone. And i only charge to 4v per cell. Most inverters just shut down higher than 400V. I know outlander does...
The inverter is the Prius Gen3 which I thought could work with bus voltages of up to 600V? Are there any other components that can cause problems at higher voltages?
Ah OK.
Well the higher the voltage the more EMI. You would need to shield cables better. Maybe also twist both HV cables...
You would need to buck HV voltage down to some 300V for the Prius DCDC converter to function.
What kind of charger do you intend to you use?

If you implement fast charging you will definitely benefit from higher battery voltage.
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Re: Smart Roadster

Post by Pete9008 »

Good point on the EMI. My inverter to motor cables should only be around 50cm and will be screened so hopefully will be OK? Battery cable could be a little longer but hopefully less critical.

The plan would be to use the Prius boost/buck stage to buck down the battery voltage to power the DC/DC when running. It will also to be used as a charger. With the higher cell count the battery voltage would always be higher than rectified mains so allowing the buck/boost to always be boosting when charging. Initially it would just be single phase 3/7kW charging although fast charging would be a possibility in the future (currently there are no fast chargers near enough me for it to be worth it!).

Having read up a bit on pack voltages it seems that OEMs are starting to move to 800V packs so I'm a little more comfortable about it. I'll limit charge voltage to keep the pack voltage below 500V (3.9V per cell, around 85%). The BMW contactors are only rated to 500V which is closer than I'd like (as I can envisage an inverter fault with a fully charged pack at high speed could caus unwanted regen which could push the voltage over the limit) so I will add an extra higher voltage contactor with opens before the BMW ones just to make sure.

The higher voltage should help extract a little more from the motor, increase the available pack power for a given battery current and increase the motor speed where field weakening starts. There is a risk of the motor not being happy with the higher voltage but the Outlander motors are cheap enough to try it and see.

I think the current plan is a 128cell main battery pack in the back of the car. This will be about the limit (or possibly just over!) what will physically fit and also about on the limit of weight that I think can be added over the rear axle. This will give 16kWh (around 11kWh usable) which is plenty for day to day use (hopefully 60-70mile range) but a little lower than I would like for the occasional longer trip. What I'd like to do to address this is to add a secondary removable pack of another 64cells (8kWh) in the front of the car which would add another 30miles to the range. This second pack would not connect to the main DC bus but would instead go through the Prius inverter buck/boost stage. The buck/boost would be controlled to keep the SOC of the two packs balanced.

This is possibly a little over complicated but does offer a few benefits:
1) With the secondary pack removed I retain the front storage compartment (the Smart Roadster doesn't have much luggage space to start with an I'm reluctant to lose any of it).
2) I don't always have to lug around the extra weight of the secondary pack.
3) The secondary pack, when not in the car, can live in the garage connected up to the solar panels being used as a solar battery. The car's likely to be out during the day and I would hate to waste the solar power during the day and then pay to charge over night.

And a few disadvantages:
1) Weight, if the secondary pack is a single piece it would weigh 60kg - too much to lift in and out without a hoist. It could be two separate packs but that adds further complexity.
2) It is the wrong side of the buck/boost to be able to charge it using the buck/boost. It should be possible to have a multistage charge process or alternatively a separate charger could be integrated into the secondary pack. The later would fit well with using it as a solar battery.

The secondary pack is probably a separate second stage to the build as everything should work just fine without it.
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Re: Smart Roadster

Post by johu »

Pete9008 wrote: Thu May 12, 2022 5:11 am The BMW contactors are only rated to 500V which is closer than I'd like (as I can envisage an inverter fault with a fully charged pack at high speed could caus unwanted regen which could push the voltage over the limit) so I will add an extra higher voltage contactor with opens before the BMW ones just to make sure.
This is the voltage the contactor can break, in my understanding the contactor should NEVER be opened during operation. So while it's closed it doesn't see any voltage anyway. An emergency stop or BMS emergency shutdown should rather be realized via triggering the emcy_stop input of the inverter or cutting power to the inverter.
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Re: Smart Roadster

Post by Pete9008 »

Thanks for the feedback and I get what you're saying, opening the contactor unexpectedly and with load would cause the inverter all sorts of grief and wouldn't do the contactor much good either. Opening it under load is not something that I would ever plan on happening but I would like to know that in an emergency it will definitely open and pushing the voltage limits doesn't help here.

I've had a look at the datasheets for a few HV contactors and they do seem to be rated for breaking load current (but it does massively reduce the life). Where I think the problem comes is if the voltage is too high, if it is they can't extinguish the arc and everything gets a bit hot and melty, hence my thought about adding an extra higher voltage contactor just to make sure!

Any thoughts on the rest of the idea, is 500V likely to cause problems for any other reasons?
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Re: Smart Roadster

Post by Pete9008 »

johu wrote: Sat May 14, 2022 5:04 pm
Pete9008 wrote: Thu May 12, 2022 5:11 am The BMW contactors are only rated to 500V which is closer than I'd like (as I can envisage an inverter fault with a fully charged pack at high speed could caus unwanted regen which could push the voltage over the limit) so I will add an extra higher voltage contactor with opens before the BMW ones just to make sure.
This is the voltage the contactor can break, in my understanding the contactor should NEVER be opened during operation. So while it's closed it doesn't see any voltage anyway. An emergency stop or BMS emergency shutdown should rather be realized via triggering the emcy_stop input of the inverter or cutting power to the inverter.
Just twigged, this is the flyback voltage again isn't it. If you try to break the current flowing in an inductor it will generate a flayback voltage to try and keep it flowing, if the motor is running this is likely to be larger than the rating of any available contactor!

Thanks for the heads up.
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Re: Smart Roadster

Post by Pete9008 »

No progress on the car as I still need to create space in the workshop. No progress on the PCB as it needs a good check before sending out and I haven't been in the right frame of mind.

I have however finished my CAN analyser tool:
CAN_Dongle1.JPG
CAN_Dongle2.JPG
It's based on an Arduino Due board running GVRET (see the excellent how to here https://openinverter.org/wiki/CAN_bus_with_Arduino_Due) and it works very nicely with the SavvyCAN software. So far I have been impressed with both. One thing worth mentioning if following the wiki how to, pins 11 and 12 on the Due need pulling low if bus forwarding isn't wanted (if they are left open all messages received on bus0 are forwarded to bus1 and vice versa). I've added a couple of switches on mine to allow this to be selected without opening the box.

I've also been on the lookout for a reasonably priced battery powered scope for a while. All the ones I've seen have either been pretty cheap and nasty, have overly optimistic specs, only single channel or too expensive. Came across this one earlier in the week https://www.amazon.co.uk/Oscilloscope-M ... B08ZHV4CS1, had a look at the comments on eevblog which seemed reasonable and so ordered one. It arrived today and first impressions are that it's not bad at all, it has a pretty good refresh rate, 2channels and seems to achieve the claimed sample rate and bandwidth. It also has a built in DMM which appears to agree with my Fluke and a built in sig gen (only 5MHz square, 20MHz sin and +-2.5V output but still useful). Not sure I believe the quoted accuracies, and before running the built in auto calibration routine a couple of the ranges had a fairly big DC offset, but once that was done it actually looks like a pretty good little scope. The biggest downside is it not having the usual scope controls so adjusting the settings is a bit of a pain. It also only comes with one fairly rubbish scope probe which is pretty poor for a 2channel scope!. It's definitely not a replacement for a desktop scope but as something to use on the car I think it will work well.

Just need some space in the workshop now and I can get started on the Roadster!
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Re: Smart Roadster

Post by Pete9008 »

Progress :D Well sort of

The car that has been blocking the space in the workshop passed it's MOT this morning so hopefully can get it moved soon. Clean pass too which I'm pretty happy about as it had been in storage for the last 25years and pretty much every component in the braking system had either seized or was leaking!

Next job is to get the Roadster into the shop, corner weight it to see what the limits are on added weight, and see what is needed to get it through an MOT.
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Re: Smart Roadster

Post by Romale »

Pete9008 wrote: Wed May 11, 2022 2:21 pm
What I'm really after here is views from anyone that has a relatively light car running the Outlander rear motor/box on how the package performs and what kind of acceleration is seen, particularly at say 40-60mph. Also interested in thoughts from people with gearboxes on their cars, do you ever change gear or does it always get left in the same one?
here I did smart using a native gearbox and an outlander engine


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Re: Smart Roadster

Post by Romale »

in a city where the limit is 50 km/h, I used only the second gear, where the limit is 80 km/h, I drove on the third and only on the tracks turned on the fourth and fifth gears
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Re: Smart Roadster

Post by Pete9008 »

Romale wrote: Wed Jun 01, 2022 9:48 pm here I did smart using a native gearbox and an outlander engine
I like that, nice work!

What battery voltage are you running and which inverter? Also any more details on your motor to gearbox adaptor?
Romale wrote: Wed Jun 01, 2022 9:53 pm in a city where the limit is 50 km/h, I used only the second gear, where the limit is 80 km/h, I drove on the third and only on the tracks turned on the fourth and fifth gears
How do you find the acceleration in each gear? Any idea what kind of 0-60 time you get?

Final question - do you know what torque that Smart gearboxes and driveshafts can take? I've looked but can't find any information on them anywhere.
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Re: Smart Roadster

Post by Pete9008 »

Still not got the car in the workshop. Noticed on the way back from the MOT for the car currently in the workshop that the engine temperature was low, turned out that it had the wrong thermostat fitted so that was an easy fix. What wasn't so easy was that while fixing it I noticed that the in car heater heat exchanger, the oil to water cooler and a couple of other hoses were all blocked. It's taken a couple of days to get it all cleared out and working but it now seems happy. The final issue was a blockage in the T for the vent pipe which meant it didn't bleed properly. It's amazing how much a little bit of air can affect the efficiency of the cooling system!

On the Roadster I have picked up this AC compressor for a good price (think it may have been wrongly been catalogued as an ICE compressor):
Compressor.JPG
Question - Are they all this large - I was expecting something about 2/3 this size!

Not really a problem as it will just fit in the space where the 12V battery currently is but if there are smaller/lighter alternatives available I would be tempted to change.

The other thing I'm wondering is whether to use it just for cooling or whether to try and use it in reverse cycle as well for heating. I realise that AC heating will only work if the ambient is a few degrees above 0C but that covers over 90% of the time. I'm also wondering whether motorised AC expansion valves will allow flow both ways if set to wide open, if so it would simplify the reverse cycle plumbing quite a bit. Any thoughts/comments on this welcome.
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Re: Smart Roadster

Post by Romale »

Pete9008 wrote: Fri Jun 03, 2022 8:15 am What battery voltage are you running and which inverter? Also any more details on your motor to gearbox adaptor?
I used three modules from Chevy bolt (30s 180ah), the kelly KHB 800 amp series controller and rewired the motor winding to the triangle connection to increase the rotation speed by 1.73 times. I also removed the resolver and made a holl emulator sensor on the as5074 chip.
at the time when I was making this car, I did not know how to control motors in the standard version at high voltage, so so.
but even at a relatively low voltage, I had good acceleration and decent torque.
the transition plate was cut out of a piece of aluminum without any drawings, I just attached a smart to the gearbox, outlined the contour and cut it out with a grinder. on the motor side, a piece of Mitsubishi's native gearbox was used for the sake of a gear worn on the motor shaft and its high-quality large bearing (it was replaced with a closed type) this gear was turned on a lathe and an tig welding washer was welded to the crankshaft emulator of the smart internal combustion engine, so the clutch was also preserved and the gearshift was very convenient.
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Re: Smart Roadster

Post by Pete9008 »

Romale wrote: Fri Jun 03, 2022 11:14 am the transition plate was cut out of a piece of aluminum without any drawings, I just attached a smart to the gearbox, outlined the contour and cut it out with a grinder. on the motor side, a piece of Mitsubishi's native gearbox was used for the sake of a gear worn on the motor shaft and its high-quality large bearing (it was replaced with a closed type) this gear was turned on a lathe and an tig welding washer was welded to the crankshaft emulator of the smart internal combustion engine, so the clutch was also preserved and the gearshift was very convenient.
So do you still have the Smart clutch, is the Outlander bearing there mainly to support the crankshaft emulator and clutch?

Do you still use the Smart electronics to control the clutch and gear change? How did the Smart electronics cope with removal of the engine?

I was wondering whether to remove the clutch and couple the motor directly to the gearbox input shaft (by welding the clutch centre plate to the outlander gear). It might mean that gear changes are only possible when stationary but I think I can live with that. By the sound of it on the road you tend to leave it in one gear most of the time?
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Re: Smart Roadster

Post by Romale »

Pete9008 wrote: Fri Jun 03, 2022 1:34 pm
Do you still use the Smart electronics to control the clutch and gear change? How did the Smart electronics cope with removal of the engine?

I was wondering whether to remove the clutch and couple the motor directly to the gearbox input shaft (by welding the clutch centre plate to the outlander gear). It might mean that gear changes are only possible when stationary but I think I can live with that. By the sound of it on the road you tend to leave it in one gear most of the time?
This car had a manual gearshift, Mitsubishi's native bearing served as a support when squeezing the clutch, so as not to create pressure on the motor axis. And I don't have this car anymore, I did this work on the client's order, but I know that it is still in use.

I prefer to keep the native clutch, it makes switching a lot easier in the conditions of the city and the highway.
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Re: Smart Roadster

Post by Pete9008 »

Good news and bad news...

Good news - the Roadster is in the workshop, I've had a good look over it and it seems fairly sound. MOT is booked for Friday (front struts could do with replacing but hopefully they are good enough for another year - front and back would all get replaced during the conversion whatever)

Bad news - I also weighed it :(

As standard, with occupants and a full tank of fuel, the car only has a spare luggage capacity of 30kg :o (and neither my wife or I are particularly heavy!)

Once all the ICE bits are out and the lightest EV parts added I could only fit 12kWh of battery pack and that would only leave a 16kg spare for luggage. This would give a range of around 60miles. Not really enough.

When combined with the facts that it is post 2001, so currently couldn't be tax free, and insurance quotes are higher than expected (£350/annum) the conversion will never pay back financially. Plus with the reduced battery capacity comes reduced performance so it may be disappointing to drive too. Overall it's not looking too good.

Options as I see it are:

1) Ignore the plated gross weight and add more batteries. Not comfortable with this.

2) Find lighter batteries. The BMW packs are 6.5kg/kWh, tesla for example are as low as 4.4. Significantly better but I can't find a configuration that would work with voltage and capacity.

3) Sell the Roadster and look for something else. The later MR2 would be a better choice (can buy a 2000year model, heavier engine to remove and more luggage capacity as standard, don't leak like the Smart!) but is even less practical and I just can't get exited about them.

Anyone got any suggestions on batteries that can get nearer 5kg/kWhr and can be configured for ~400V and 16kWH? Ohh - and ideally don't cost a fortune!
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Re: Smart Roadster

Post by mjc506 »

A few thousand 18650 cells and a spot welder?

Any scope for reducing weight by replacing non-structural stuff (plastics, bonnet, boot cover etc) with carbon? Lighter seats? Probably a fair bit of money for minimal gains though :-(
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Re: Smart Roadster

Post by marcexec »

Lithium 12V battery? Might as well throw the lead out...
Lighter wheels? probably difficult to get, though.
Back to the Outlander drivetrain -gearbox weight +axle fabrication

Best of luck either way!
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Re: Smart Roadster

Post by Pete9008 »

mjc506 wrote: Wed Jun 08, 2022 11:11 am A few thousand 18650 cells and a spot welder?
Pretty much my conclusion! Briefly considered it but no. Did look to see whether Tesla packs could be modified and it seems they can be but it's not something I'd be comfortable doing myself (the chance of a bit of swarf ending somewhere it shouldn't is too high!).
mjc506 wrote: Wed Jun 08, 2022 11:11 am Any scope for reducing weight by replacing non-structural stuff (plastics, bonnet, boot cover etc) with carbon? Lighter seats? Probably a fair bit of money for minimal gains though :-(
The Smart's weight is already pretty well cut down here, it already has plastic body panels and rear windows. It even has 3 stud wheels and non-vented front disks presumably to save weight. It has the leather seats which have a reputation for being heavier but which are also heated and from a range point of view I think the heating is worth the extra weight. They are also fairly comfy while I find a lot of after market seats pretty uncomfortable. Using carbon would be nice but the gains are probably not worth it in terms of cost. All worth thinking about though.
marcexec wrote: Wed Jun 08, 2022 2:52 pm Lithium 12V battery? Might as well throw the lead out...
Lighter wheels? probably difficult to get, though.
Back to the Outlander drivetrain -gearbox weight +axle fabrication
Definitely! I'd pretty much decided to keep the Roadster gearbox before weighing the car but it's going to have to go. The lead 12V battery is going too, need the space for the electric AC pump. I know what you're thinking - the AC pump is heavy and reduces range. Agree completely here but I get terrible hay fever in the spring/early summer so open top motoring is a non starter and since the coupe version of the Roadster is a bit of a greenhouse the AC is staying!

So where does this leave things?

Well first it passed its MOT this morning :D The strut I was a worried about is a bit rusty but still sound so not even an advisory. The only thing anywhere close to an advisory was the seal around the fuel filler cap which is just showing slight signs of starting to crack, but that will be going in the bin if I convert it anyway!

So the big question, do I continue with the conversion or do I sell it (at a good profit too now it has a MOT) and look for something else?
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Re: Smart Roadster

Post by Pete9008 »

I think I know the answer but I think I'm going to run through the argument here just to get it clear in my head, and also to see if I still feel the same way once I see it in black and white.

Roadster Cons
1 It's tiny, you do feel a little vulnerable driving it.
2 Reasonable luggage volume but will have virtually no luggage capacity left following conversion (10-15kg with 2 occupants)
3 It's a soft top (see comments above on hayfever). Which leaks! Would much prefer a permanent hardtop. Removable hard tops are available but for silly money (~1k second hand!) and still leak!
4 Noisy! mainly exhaust and engine though.

Roadster Pros
1 I quite like it, it's fairly fun, feels quick even when you're not going that fast.
2 The handling is a nice compromise, it soaks up bumps well enough but corners nicely and is very precise.
3 Reminds me a lot of a Mk2 CRX (one of my favourite previous road cars and my current track day toy)
4 My wife has now had a go in it and has decided she quite likes it too!

Seeing it written down above makes me realise that the cons are pretty much all logical and can be fixed by choosing another car. All the pros are emotional and may well be lost by moving to another car. Logically I should switch to another car.

But I'm not going to!

The only way I can stay interested in a project is if I enjoy it and that only happens if I'm emotionally invested in the result - I need to believe that the end product is worth all the time/effort. When researching possible cars there were three main candidates, the Smart Roadster, MR2 Roadster, 1st gen SLK. The MR2 and SLK would probably be better conversion candidates, more space, more luggage capacity, more practical, fewer leaks!; the trouble is I just can't get excited about them - so it's going to have to be the Smart. Plus TBH pro point 4 above probably counts for as much as all the others combined (especially as she's in charge of the credit card)!

So the plan:
1 Fix a few bits and pieces - fix iffy heater fan and door switch, new dampers (the current ones are ok but tired, the ride/handling is good but could be better)
2 Run the car for a couple of months. Take CAN logs and try to figure out the comms protocols
3 Pull out the rear subframe and weigh everything. I think my numbers may be a little pessimistic (or at least I'm hoping so), the Smart engine weight I have may be dry weight, it might not include ancillaries, etc.
4 If the weights indicate I can fit at least 12kWh of battery in, and I think I can, then go ahead with the conversion, if not put it back together until batteries improve!
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Re: Smart Roadster

Post by Pete9008 »

Question -

I've come across the idea that 8kWh of battery is roughly equivalent to 1gallon of petrol - if you car did 30mpg in your typical driving style before conversion then 8kWh of usable battery capacity will give you 30miles of range using similar style of driving following conversion (assuming similar vehicle weight before and after?).

This seems to tie in well with my range calculations but wondered how it compares with everyone real world experience?

I suppose that the main problem is that some ICE car engines are more efficient than others (particularly comparing old with new) but it if it came somewhere close it would be a nice simple metric as it's independent of driving style, car size, weight, etc
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Re: Smart Roadster

Post by marcexec »

Glad to hear you're pushing on!
Maybe these projects help with some ideas about range?

https://www.autoweek.nl/reviews/artikel ... kw-2004-2/ // https://translate.google.com/?sl=auto&t ... =translate

https://eveurope.eu/en/projects/smart-roadster/

for petrol consumption check out this German DB:
https://www.spritmonitor.de/de/uebersic ... owerunit=2
(ignore the EV, likely a ForTwo)
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Re: Smart Roadster

Post by Pete9008 »

marcexec wrote: Mon Jun 13, 2022 8:38 am Glad to hear you're pushing on!
Maybe these projects help with some ideas about range?

https://www.autoweek.nl/reviews/artikel ... kw-2004-2/ // https://translate.google.com/?sl=auto&t ... =translate

https://eveurope.eu/en/projects/smart-roadster/

for petrol consumption check out this German DB:
https://www.spritmonitor.de/de/uebersic ... owerunit=2
(ignore the EV, likely a ForTwo)
Thanks for the links. There is quite a big variation in fuel economy there (35-72mpg) but the average of 53 is in line with what I'm hoping for :)

Been fixing a few more issues with the Roadster, one door lock and the heater blower weren't working but sorted now. You always know it's not going to be an easy repair when you find someone has been there before you and you have to spend most of your time removing the previous 'repairs'! Also coded up a spare key fob as the Smarts have a habit of randomly losing key programming and I only had the one key.

Ordered a few more bits the first of which has arrived:
I-Pace Valve Block.JPG
Air con valve block from an I-Pace, hopefully it will provide two heat exchangers complete with expansion valves and solenoid valves to control them plus a pair of what I'm hoping can be used as refrigerant flow control valves. Still need to figure out the control interface but I'll start a new thread to cover that. When I have a chance I'll also sketch out what I have in mind for the AC (I'm hoping to achieve both cabin and battery heating and cooling from it without too much plumbing complexity). It may not work but even if I only use a few of the bits of the above it's still worth the cost.
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Re: Smart Roadster

Post by arber333 »

Pete9008 wrote: Wed May 11, 2022 4:24 pm
arber333 wrote: Wed May 11, 2022 4:13 pm I would not advise to go over 104S. I did and i am at the end of my inverter comfort zone. And i only charge to 4v per cell. Most inverters just shut down higher than 400V. I know outlander does...
The inverter is the Prius Gen3 which I thought could work with bus voltages of up to 600V? Are there any other components that can cause problems at higher voltages?
DCDC, AC compressor, charger, electric heater... practicaly everything HV needs higher rating.
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Re: Smart Roadster

Post by Pete9008 »

arber333 wrote: Sat Jun 18, 2022 2:59 pm
Pete9008 wrote: Wed May 11, 2022 4:24 pm
arber333 wrote: Wed May 11, 2022 4:13 pm I would not advise to go over 104S. I did and i am at the end of my inverter comfort zone. And i only charge to 4v per cell. Most inverters just shut down higher than 400V. I know outlander does...
The inverter is the Prius Gen3 which I thought could work with bus voltages of up to 600V? Are there any other components that can cause problems at higher voltages?
DCDC, AC compressor, charger, electric heater... practicaly everything HV needs higher rating.
Agreed, if I do use a higher voltage then I'd either have used the Prius buck/boost block, or MG1 and external inductor and cap, to drop it down to a lower voltage for all these parts.

However, having now weighed the car I very much doubt that I can get enough cells in there to cause a problem and I think it's going to be limited to the standard 96 cells. This means the AC and heater can run directly off the pack and also simplifies the BMS. What I'm still considering though is having an auxiliary, removable pack that can be fitted to add extra capacity. This would run at a lower voltage and use the buck/boost block to supplement the main battery pack.

The main issue I'm struggling with at the moment is charging. With a higher pack voltage I had planned to also use the buck/boost block in boost mode as a charger. Unfortunately, with the lower pack voltage this doesn't seem possible (the buck/boost block can only boost in the forward direction or buck in the reverse direction). Not sure what to do here but it might mean using a separate OEM charger which I'm not keen on - more weight, more cost, more space - but probably a better overall solution. The alternative is to add an extra IGBT block on the input to the buck/boost block to allow it to buck in both directions but it would be difficult to control it well enough (especially as I'd like to include some degree of power factor correction which complicates things further).

Basic plan:
Phase 0 - Run car and take CAN logs for a couple of months till the current insurance expires.
Phase 1 - Basic operation - battery, motor, basic charging. AC and heating mechanically installed but not operational. Hopefully this year.
Phase 2 - add control system and wiring for HVAC to get it operational. Improved charging.
Phase 3 - if range proves inadequate add auxiliary battery pack.
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