Jump to content
Kermit68

Some data to fine tune existing alpha model

Recommended Posts

Hi, last weekend I had some spare time that I used to run some consumption test with my I Pace (20" wheels, no pano roof, air suspension) that I would like to share as it could be useful to fine tune the existing ABRP I Pace model.

The test was a 300 km roundrip made of 3 legs (each way) of motorway @130 km/h, country roads @95 Km/h speed with some 600 m elevation gain and a final mountain road at variable speed from 40 km/h to xxx km/h with another 1100 m elevation gain. Temperature from 29C (motorway) to 16C (mountain top), no air con. Started fully charged and got back home with 9% left.
Very little traffic in the motorway so the car was running @130 km/h as set in the cruise for 99,9% fo the time.

Useful data I can report are:

- using a value of 245 Wh/Km @110 Km/h in ABRP I get a consumption estimation very much in agreement with the real data (about 1% more) and over 300 km I think it'a pretty good result and confirms the genral experience of I Pace owners that reference consumption acutally proposed as default (271 Wh/Km @110 Km/h) quite excessive.

- average consumption of 262 Wh/Km @130 Km/h measured over a 52 km leg (50m elevation loss, so close to negligible).

If helful I can report exacly my trip but I don't know how to do it: save the tirip in ABRP and share it or just a screen shot?

Link to comment
Share on other sites

@Kermit68 - The best way to tackle this, if you're so inclined, is to go for a drive on some flat road, and drive 10-20 minutes at each given speed, resetting your trip odometer for each and recording the efficiency.

If you can give me a few data points, for example:

  1. 30km/h
  2. 60km/h
  3. 90km/h
  4. 120km/h
  5. 150km/h (If safe)

That would be sufficient to define the range a little better.

Link to comment
Share on other sites

Ok, it's not an impossible task. My main problem is to find a flat path but once spotted not too far from my home it's feasible. Even @150km/h, tecnhnically speaking it's not legal in Italy but I would be a laier if I'd say I never drived the I Pace (or my motorbike) at that speed ... ?

I'll get back to you with some numbers soon.

Link to comment
Share on other sites

10 hours ago, Kermit68 said:

Ok, it's not an impossible task. My main problem is to find a flat path but once spotted not too far from my home it's feasible. Even @150km/h, tecnhnically speaking it's not legal in Italy but I would be a laier if I'd say I never drived the I Pace (or my motorbike) at that speed ... ?

I'll get back to you with some numbers soon.

Sounds great! I ought to put a section in the OP to ask for consumption info at different speeds, then people can knock one or two out and we can get a full model.

Link to comment
Share on other sites

Hi Jason, as promised I have some data for you. First some extra info:

  • all data collected after battery warm up (no less than 20 km run before starting the measurements)
  • all data have been collected at external temperatures between 29C and 31C, no air con on (it got a little hot in the car but I wanted "clean" data)
  • all data refers to an I Pace equipped with 20" summer tires and air suspensions (it is supposed to make some difference compared to spring coils above 105 km/h as with A/S the car lowers to improve efficiency)
  • all data have been collected on a loop path or corrected for minor elevation gain / loss (always less then 20 meters) using the formula E =m*g*h where E is the energy used/gained for elevation gain/loss, m = 2200 kg (estimated mass of the car), g = 9,81 m/s2 and h elevation gain / loss in meter. The result has been diveved by 3.6 E06 to convert from Joule to kWh.
  • I also measured the difference between odometer speed and real speed using a Garmin GPS

Here are the numbers:

Reported average speed Real average speed Consumption

Km/h                                Km/h                      W/Km

28                                      26                           127

60                                      56                           126

90                                      86                           181

120                                   115                          252

149                                   144                          354

I also have some extra data to get a better estimation of the real speed / measured speed (km/h) : 130 = 124 and 50 = 47

Final consideration: I'm pretty confident on the measues at 60, 90, 120 and 150 Km/h while for the 30 km/h my number can be not so accurate. I could not find a flat or semi flat road where I could drive @ 30 Km/h safely around Rome, so I had to comprimes a little bit and the number I report has been measure on a 2.5 km path, kind of short ...

Please let me know if you need more info from me.

Ciao

 

Edited by Kermit68
Link to comment
Share on other sites

On 9/11/2019 at 2:47 AM, Jason (ABRP) said:

Sounds great! I ought to put a section in the OP to ask for consumption info at different speeds, then people can knock one or two out and we can get a full model.

Hi Jason, did you have the time to give a look to the data I posted a few days ago?

Link to comment
Share on other sites

On 9/20/2019 at 4:03 PM, Kermit68 said:

Hi Jason, did you have the time to give a look to the data I posted a few days ago?

Thanks for the reminder, I added that into my model, and it was a very nice fit! Improved the curve by a lot (loses more range at high speeds than I originally estimated), though it did improve the reference consumption by 10Wh/km (1kWh/100km).

If anyone else would like to contribute similar data points I think we're getting close to bumping the I-Pace model to Beta.

Link to comment
Share on other sites

11 hours ago, Jason (ABRP) said:

Thanks for the reminder, I added that into my model, and it was a very nice fit! Improved the curve by a lot (loses more range at high speeds than I originally estimated), though it did improve the reference consumption by 10Wh/km (1kWh/100km).

If anyone else would like to contribute similar data points I think we're getting close to bumping the I-Pace model to Beta.

I'm glad the data were useful. I'll post on the UK and Italy I-Pace forum that you're looking for more data, I hope you'll gahter more.

One question about planning: since there is a difference between indicated speed by the odometer and the real speed, how I'm supposed to manage this when planning using ABRP? For example, if I set the reference speed in ABRP to 100% for planning, then on the highway where speed limit is 130 km/h should I set the cruise to 130 or to 137 which is the settings that actually makes me travel at real 130 km/h?

Link to comment
Share on other sites

On 9/10/2019 at 3:42 PM, Jason (ABRP) said:

@Kermit68 - The best way to tackle this, if you're so inclined, is to go for a drive on some flat road, and drive 10-20 minutes at each given speed, resetting your trip odometer for each and recording the efficiency.

If you can give me a few data points, for example:

  1. 30km/h
  2. 60km/h
  3. 90km/h
  4. 120km/h
  5. 150km/h (If safe)

That would be sufficient to define the range a little better.

Sorry for not exact data  but maybee my examples of driwing will help.

I have Ipace  FE , and alreaday 16 600 Km - AVG  25 kWh/100km (there was no winter time and realy few rain)

Temperature between 10-30°C

Last 4800 AVG 70 km/h avg 24,3 kWh/100 Km

Some trips

18°C Prague - Brno / Highway  211 Km AVG 100Km/h -- 28.5 kWh/100 Km

25°C HW 71 km AVG 97   -- 24,5 kWh/100Km

23°C Road 68 Km AVG 68 km/h -- 22,1 kWh/100km

25°C COMB 80%HW  108 km  AVG 91 -- 24,3 kWh

30°C HW 112 km AVG 106 km/h  -- 30,10 kWh

 

 

Edited by Adame
Link to comment
Share on other sites

19 hours ago, Jason (ABRP) said:

Thanks for the reminder, I added that into my model, and it was a very nice fit! Improved the curve by a lot (loses more range at high speeds than I originally estimated), though it did improve the reference consumption by 10Wh/km (1kWh/100km).

If anyone else would like to contribute similar data points I think we're getting close to bumping the I-Pace model to Beta.

Jason, I have some doubt about highway consumption after you updated the model. I simulate a trip from Rome to the Ionity station in Valdichiana Outlet village, 178 km. Based on the updated model I should get there with 28% SOC left. My experience was I got there with 36% SOC, AC on all the time (ext. temperature 38C), total trip time 1:44 vs the 1:41 planned, so very comparable. Are you sure about the corrections you made with my data?

Link to comment
Share on other sites

We intentionally add 10% buffer to the efficiency over actual data for all cars to account for normal variations in conditions, which would account for the 8%point difference.  It should be a better match to your actual consumption than before, as before the suggested reference consumption was a little higher (less efficient).

I'll add in @Adame's data when I have some time and see if I still get similar results.

Of course, if anyone wants to get more data points at highway speeds (the faster the better) that would help refine that region of the curve.

Link to comment
Share on other sites

I took my I-Pace from Noordwijk (NL) to Chur (CH), 987 km average Kilowatts 28,7 per 100km. Temp around 5C. The trip was 14,5 hours it took my wife only 9.5 with her ford Galaxy. The averaged loading speed was somewhere around 80kw/h. Not the 100 kw/h Jaguar promised me. I don’t have the latest update yet maybe this will help.  It rained the whole day but it was not very windy.

It took my brother also an I-pace driver 1 hour shorter het took the road which was suggested by abetterrouteplanner (Stuttgart – Ulm) I stayed on the 5 (Basel -Zurich).

I will drive home to Noordwijk on the 5th of January Then I will also take the Stuttgart-Ulm route.

 

Link to comment
Share on other sites

Hi Jason, as you probably already know, Jaguar is rolloing out a major update for the I-Pace named H264. In theory is should give better perfoprmance in cold temperatures but honestly I've not seen much difference in my test after the update, probably because winter in Italy is not cold enough (and this year is even warmer than the last years ...) so I'm not sure if this will make any difference for your planning algorithm. On the other hand there is a specific change that probably you should take into account for your model: JLR has changed the zero set point of the SoC by reducing the buffer at the very low end of the discharge status of the battery. This has changed the number of kwh that the software is using to calculate the SoC so if before the H264 update it was commonly accpted that 100% SoC meant about 82 kwh available, now the number is more like an 84 or even 85 kwh. I don't know if this is going to affect your model calculation for the residual SoC calculation, but I though you should be aware of that.

Ciao, Alessandro

Link to comment
Share on other sites

On 1/5/2020 at 2:42 PM, Kermit68 said:

Hi Jason, as you probably already know, Jaguar is rolloing out a major update for the I-Pace named H264. In theory is should give better perfoprmance in cold temperatures but honestly I've not seen much difference in my test after the update, probably because winter in Italy is not cold enough (and this year is even warmer than the last years ...) so I'm not sure if this will make any difference for your planning algorithm. On the other hand there is a specific change that probably you should take into account for your model: JLR has changed the zero set point of the SoC by reducing the buffer at the very low end of the discharge status of the battery. This has changed the number of kwh that the software is using to calculate the SoC so if before the H264 update it was commonly accpted that 100% SoC meant about 82 kwh available, now the number is more like an 84 or even 85 kwh. I don't know if this is going to affect your model calculation for the residual SoC calculation, but I though you should be aware of that.

Ciao, Alessandro

This is great information, we've updated the efficiency numbers for the same software update, but weren't aware that the capacity had been expanded as well.  Do you have a source on that, or perhaps could you take measurements of some kind to determine the newly available capacity?

Link to comment
Share on other sites

6 hours ago, Jason (ABRP) said:

This is great information, we've updated the efficiency numbers for the same software update, but weren't aware that the capacity had been expanded as well.  Do you have a source on that, or perhaps could you take measurements of some kind to determine the newly available capacity?

As far as I now, JLR has not reported the new number as well as they never officially reported the previous one. Most if not all I-Pace owners with Android phone are using an app called Wattcat developed by a very nice and clever Norwegian guy that among many other info it is reporting not the SoC % but also the available kwh. Since the info is coming from JLR api we always consider that pretty accurate and the numbers I was reporting to you (84 or 85 kwh) after full recharge are coming from that. My car is 6 months old, it has 8000 km and it has been fast charged only 3 times so I'm assuming battery degradation should be negligible and now it's consistently getting between 83.5 and 85 kwh at the end of the charge. At least for my experience the average is closer to 84 than to 85, so to be conservative I'd use that one. Other owners on the uk I pace forum are reporting similar numbers and nobody has reported anything above 85 kwh. I do understand it's not an official number nor something coming from scientific experiment but I guess that for the purpose of estimating the range 84 kwh should be close enough to reality considering that range is affected by many other factors on which we may even a worst estimation (wind, real battery degradation,  effects of temperature on battery for example ).

In any case, if you like me to run some particular test just let me know. I really appreciated your work and being supportive is the minimum I can do.

Link to comment
Share on other sites

There is no extra battery capacity as such. What they did was move the point at which the car reported “zero miles” lower. Nobody knows the exact figures outside of Jaguar but let’s say it used to say you had zero miles left at 4 kWh, now it says zero miles at two kWh instead (made up numbers for demonstration only). You could always access that 4 kWh before but that was your buffer where you could still drive even though the car was reporting zero miles. Now you get less miles after the car goes to zero, but no actual extra battery capacity at all. The top buffer (which is the only way they could unlock more actual capacity) has remained unchanged. 

Link to comment
Share on other sites

On 2/5/2020 at 11:29 AM, Abu Dhabi Dude said:

There is no extra battery capacity as such. What they did was move the point at which the car reported “zero miles” lower. Nobody knows the exact figures outside of Jaguar but let’s say it used to say you had zero miles left at 4 kWh, now it says zero miles at two kWh instead (made up numbers for demonstration only). You could always access that 4 kWh before but that was your buffer where you could still drive even though the car was reporting zero miles. Now you get less miles after the car goes to zero, but no actual extra battery capacity at all. The top buffer (which is the only way they could unlock more actual capacity) has remained unchanged. 

I agree. Nobody is talking about "extra battery capacity" but rather that zero SOC reported by the car has changed. This may have an effect on Jason model as it gives an indication of the SOC level you should arrive and leave the charger.

Link to comment
Share on other sites

24 minutes ago, Abu Dhabi Dude said:

Just wanted to say that after doing a test route with the app for my video review I am amazed at how good the iPace model is now. It was incredibly accurate. Great job!

Are you using the default 263 wh / km @110 Km/h or a lower value? I'm asking because for me the "magic" number is rather 250 wh / km. Just curious ... ?

 

Link to comment
Share on other sites

1 hour ago, Kermit68 said:

Are you using the default 263 wh / km @110 Km/h or a lower value? I'm asking because for me the "magic" number is rather 250 wh / km. Just curious ... ?

 

I intentionally used the default setting for the test. I have the 22” wheels and it worked out to be almost exactly correct. The test was done on a motorway drive, mainly at 70 mph with a stretch at 60 and another stretch at 50 and a short 30 mph limit before reaching the fast road. Mainly 70 limits though. 
 

PS I know they changed the model recently. The default figure is now 406 kWh/100 miles (used to be 413 I think). Not sure what the km value is for that but I’m pretty sure it’s less than 263 now. I think 406 is around 250. 

Edited by Abu Dhabi Dude
Link to comment
Share on other sites

23 hours ago, Abu Dhabi Dude said:

I intentionally used the default setting for the test. I have the 22” wheels and it worked out to be almost exactly correct. The test was done on a motorway drive, mainly at 70 mph with a stretch at 60 and another stretch at 50 and a short 30 mph limit before reaching the fast road. Mainly 70 limits though. 
 

PS I know they changed the model recently. The default figure is now 406 kWh/100 miles (used to be 413 I think). Not sure what the km value is for that but I’m pretty sure it’s less than 263 now. I think 406 is around 250. 

I tried right now both the old website and the new abrp website and they are both using 263 wh / km @110 km/h. But I'm always changing it to 250 for my planning so no big deal even though I would like to see the model further tuned and passed at a beta stage.

Link to comment
Share on other sites

They only have one model for the iPace. The range varies according to wheel size. Maybe the model is set up for 22” wheels (which I have) and consumption needs to be adjusted for the smaller one? Just a thought. Not sure what wheels you have. 

Edited by Abu Dhabi Dude
Link to comment
Share on other sites

11 minutes ago, Abu Dhabi Dude said:

They only have one model for the iPace. The range varies according to wheel size. Maybe the model is set up for 22” wheels (which I have) and consumption needs to be adjusted for the smaller one? Just a thought. Not sure what wheels you have. 

Actually we were both right. I switched in my preferences from metric to British units  and I got 406 wh / mi as you told me. 406 / 1.609 (1 mile is 1.609 km) equals to 252. Maybe it's just a problem of data non correctly updated.

My car has 20" btw.

Link to comment
Share on other sites

Lol! That explains a lot! Thanks for working it out. Did seem weird. I’ve just checked in my app and I’m the same. If I set “British” in the settings menu for units then it goes to 406. If I set metric it goes to 263. I found 406/252 was pretty much perfect. The 263 I think is the old value but I can’t figure out why it would be different depending on what setting you pick. Easily fixed though now we’ve pinned it down. 

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


×
×
  • Create New...