Who do I get higher arrival charge than specified?

[Björn S]

I'm trying to understand when/why ABRP plans routes with higher arrival charge than I specify in the settings.

Here's an example from a Model 3 plan from Stockholm to Skellefteå with 5% arrival charge set (link):

First it tops up in Gävle in order to be able to reach Sundsvall with 5% left. All good. Then it charges to 53% in Gävle, which means it reaches Örnsköldsvik with a 10% charge. Why?

As I understand it, a shorter charge in Sundsvall would save time both in Sundsvall (due to shorter charge) and Örnsköldsvik (due to higher charge speed at low %).

The only explanation I can think of is that ABRP estimates a much lower charge speed at <10% than at >10% (and at >70%). Is that what is happening?

[Bo-ABRP]

ABRP finds a route by optimizing the total time, charging+driving+overhead. Getting to a charger in a modern Tesla with less than 10% is usually not a good idea, timewise, so ABRP will typically avoid that. There is no cost to getting to the destination at very low SoC %, so it will always arrive with the lowest allowed SoC. 

The ABRP optimizer is currently slightly granular and will typically optimize the time in steps of 5% charging - which is why it sometimes jumps from 10% to 15% arrival SoC if that turns out to be (slightly) better.

[Björn S]

I tried changing arrival charge (both charger and destination) to 4% and the schedule changed in a rather unexpected way:

[Björn S]

That makes sense. Thanks!

[MikeUSA]

On 11/18/2018 at 3:06 AM, Bo (ABRP) said:

ABRP finds a route by optimizing the total time, charging+driving+overhead. Getting to a charger in a modern Tesla with less than 10% is usually not a good idea, timewise, so ABRP will typically avoid that. There is no cost to getting to the destination at very low SoC %, so it will always arrive with the lowest allowed SoC. 

The ABRP optimizer is currently slightly granular and will typically optimize the time in steps of 5% charging - which is why it sometimes jumps from 10% to 15% arrival SoC if that turns out to be (slightly) better.

 

On 11/18/2018 at 3:06 AM, Bo (ABRP) said:

ABRP finds a route by optimizing the total time, charging+driving+overhead. Getting to a charger in a modern Tesla with less than 10% is usually not a good idea, timewise, so ABRP will typically avoid that. There is no cost to getting to the destination at very low SoC %, so it will always arrive with the lowest allowed SoC. 

The ABRP optimizer is currently slightly granular and will typically optimize the time in steps of 5% charging - which is why it sometimes jumps from 10% to 15% arrival SoC if that turns out to be (slightly) better.

How do I specify a minimum SoC of 20%??

[Jason-ABRP]

7 hours ago, MikeUSA said:

How do I specify a minimum SoC of 20%??

Settings > Goal Arrive Charge
Settings > Charger Arrive Charge

Goal arrive charge is your final charge when you reach your destination, so you can set it to a higher value if you want to be able to drive around there.  Charger Arrive Charge is how much you want to have left at each stop. 

[MikeUSA]

THANKS!!!

[SteveD]

Goal arrive charge and charger arrive charge seem to be referring to the same thing.  How are they different?  I don't want to arrive with less that 20% charge and don't mind charging longer with less stops.  What is the ideal charge to have when leaving a place? 65-75%?

Edited May 9, 2019 by SteveD

[Jason-ABRP]

21 hours ago, SteveD said:

Goal arrive charge and charger arrive charge seem to be referring to the same thing.  How are they different?  I don't want to arrive with less that 20% charge and don't mind charging longer with less stops.  What is the ideal charge to have when leaving a place? 65-75%?

They're different in case you want to arrive at your final destination (Goal arrive charge) at a much higher SoC than your interim stops (charger arrive charge).  Let's say you're driving to a friend's house, and you want to make sure you have enough charge to floor it and give them the real EV experience for a bit once you get there, you might set your goal arrive charge to 50%, but your charger arrive charge to your standard 20%.

Your ideal charge to leave anywhere depends on your vehicle's charge curve.  We take that into account and find the ideal % to leave each charger accounting for distance, speed, how far off the route you have to go to find your next chargers, and a host of other factors.