Volvo XC60 Alternator Control - Brake Energy Regeneration

[Wardair]

I am looking for information on when the 'Brake Energy Regeneration Mode' was introduced to the XC60 Alternator Control and what models this function is operative on and can it be switched on/off with VIDA?
My current understanding is that from 2010 Volvo introduced a Battery Monitoring Sensor and this is used to check Battery SoC and on some vehicles when the battery is above a certain percentage the Alternator Control changes from 'Conventional Charging' to 'Brake Energy Regeneration, Quick' (in daytime only) 'Brake Energy Regeneration, Slow No Discharge' is the mode used during the night.
Can anyone provide a link to further technical information on this feature?

Still reading and learning. My concern with this is there is a large discharge on acceleration which looks like the Alternator is used as a motor to assist engine, is this true?

Here is a great video showing the function in action:-
https://www.youtube.com/watch?v=6-GfTlLmNjU

[Clan]

Originally Posted by Wardair

I am looking for information on when the 'Brake Energy Regeneration Mode' was introduced to the XC60 Alternator Control and what models this function is operative on and can it be switched on/off with VIDA?
My current understanding is that from 2010 Volvo introduced a Battery Monitoring Sensor and this is used to check Battery SoC and on some vehicles when the battery is above a certain percentage the Alternator Control changes from 'Conventional Charging' to 'Brake Energy Regeneration, Quick' (in daytime only) 'Brake Energy Regeneration, Slow No Discharge' is the mode used during the night.
Can anyone provide a link to further technical information on this feature?

Still reading and learning. My concern with this is there is a large discharge on acceleration which looks like the Alternator is used as a motor to assist engine, is this true?

Here is a great video showing the function in action:-
https://www.youtube.com/watch?v=6-GfTlLmNjU

No the alternator is not used as a motor except in the D6 hybrid. There are very comprehensive details of Brake energy Regeneration in VIDA .

[johnnyoro]

Hi I think from about 2010 volvo started fitting so called smart alternators and the fluctuating charge current is caused by this .
My car does the same and as you say once the battery has reached a certain soc the alternator then just tops it up when the engine is on the overrun. Similarly when you apply power the alternator cuts out to reduce the load .
Just Another way of helping to reduce emmisions
Hope this helps

[Wardair]

Hi Clan and Johnnyoro
Thanks for your reply.
I do not have VIDA but my Diag Tool does show live data streams and when the Alternator is in 'Brake Regeneration, Quick' mode on my car there are very large battery discharge currents when accelerating hence my question.
I did read somewhere that the direct drive alternators are actually used as motors to briefly assist the engine during acceleration is this true?

[johnnyoro]

Hi you are probably thinking of the mild hybrids that use the alternator as a motor at times

[Wardair]

Can anyone explain why there is a 50A battery discharge when the vehicle accelerates, that is a a lot of power (600W) more than is needed just to run the vehicle?
It certainly looks strange to me if Alternator Charge Mode 2 is just turning the alternator off on acceleration.
Alternator Charge mode 3 (nighttime) has the comment 'no discharge' so what exactly is the different between mode 2 and mode 3?

[Clan]

Originally Posted by Wardair

Can anyone explain why there is a 50A battery discharge when the vehicle accelerates, that is a a lot of power (600W) more than is needed just to run the vehicle?
It certainly looks strange to me if Alternator Charge Mode 2 is just turning the alternator off on acceleration.
Alternator Charge mode 3 (nighttime) has the comment 'no discharge' so what exactly is the different between mode 2 and mode 3?

760 watts = 1 hp

[Wardair]

Hi Clan,
I am aware of electrical power to hp conversion but my question was does the car need 600 watts to run and take 50A from the battery without any alternator input?
With no extra electrical items (heated mirrors rear screen etc) on other than lights?
If so then the alternator is just turned off and on plus Alternator Charge Voltage Request is increased during overun/braking when Brake Energy Regeneration,Quick mode is operative.

Just trying to understand what is clearly an interesting charging philosophy and it does raise the question of what type of battery should be fitted (start/stop capable)?

[Clan]

Originally Posted by Wardair

Hi Clan,
I am aware of electrical power to hp conversion but my question was does the car need 600 watts to run and take 50A from the battery without any alternator input?
With no extra electrical items (heated mirrors rear screen etc) on other than lights?
If so then the alternator is just turned off and on plus Alternator Charge Voltage Request is increased during overun/braking when Brake Energy Regeneration,Quick mode is operative.

Just trying to understand what is clearly an interesting charging philosophy and it does raise the question of what type of battery should be fitted (start/stop capable)?

There are many heavy power using components on the car these days, the Alternators are well over 100 Amps . the power steering rack, the NTC Electric heater element, Heated rear Window, heated screen , the electric fan has a huge motor on it. Hopefully they are not all needed at the same time but that has to be allowed for. There are or more modules in the car, each may take very little but everything adds up. Just standing with the ignition on needs a 25A power supply to keep it all going when doing VIDA work. I believe the alternator charges fully with foot off the throttle and when braking, that is why a battery does not charge up from flat in the cat. With a good battery which maintains fully charged the system works fine, but first signs of sulphating it can not get their without fully charging external.

The alternator will compensate immediately for any extra load you turn on or is needed eg power steering ....

Regarding the type of battery there are AGM and Advanced flooded Mat , I just use the correct part Number from Volvo.

[GMcL]

Originally Posted by Wardair

Hi Clan,
I am aware of electrical power to hp conversion but my question was does the car need 600 watts to run and take 50A from the battery without any alternator input?
With no extra electrical items (heated mirrors rear screen etc) on other than lights?
If so then the alternator is just turned off and on plus Alternator Charge Voltage Request is increased during overun/braking when Brake Energy Regeneration,Quick mode is operative.

Just trying to understand what is clearly an interesting charging philosophy and it does raise the question of what type of battery should be fitted (start/stop capable)?

If you take a look at this Varta website it explains the difference between charging a standard lead acid battery and AGM/EFB for start-stop.

https://batteryworld.varta-automotiv...ults-interpret

The graph shows a dip after starting with a regular battery SLI shows a dip and the alternator immediately returning to full charge, with start-stop the system allows the battery to drain down before charging back to 80%-ish allowing headroom for charging while braking or on overrun.

600W could be your car stereo blasting out your bangin' chunes.