Regen and Active Cruise Control

[Dragonfly]

Has anyone noticed that when you use ACC, you don't get any negative values on the power meter, I can't say for sure, but that implies that it is not using the KERS for regen. However going down a hill, or when someone pulls into the space, you can feel it pull back, but still no negative power reading.

I did feel it was slightly more efficient on the battery, than when I drove manually, but didn't generate as much power back, even when running in petrol mode.

 

[PAULinTHAILAND]

Think you're right, but haven't seen any official to confirm it.

 

[VenumX]

My guess is ,... for the ACC to work correct and SAFE,.. it will always use the brakes and will never depend on braking by using the regen ability,... thats just my guess

I dont have the car yet,.. but if it was my system it wouldent rely on regen braking while using acc,.. thats not safe....

Greetz

 

[jem111111]

I noticed that as well , but I only use acc in traffic ,(which is great and relaxing once you get to trust it will break lol ),so I wouldn't expect much regen anyway.

 

[hermitdave]

One thing I noticed with cruise control in general especially with Leaf30 was they of user a few % more each time.

Braking system should always regen irrespective of whether friction brakes are being activated or not.

MG are relatively new in this field

 

[Dragonfly]

Having had a play with ACC, while on the hybrid screen, I can confirm that it never regens, however there also appears to be more "surplus" power diverted to the battery when in "Auto Mode", obviously no surplus power in EV mode.

What that amount to, is 11% power regenerated when I drive, 9% using ACC on the same 25 mile section of road, in similar conditions.

 

[VenumX]

So the ICE is just making power that gets transferred to the battery ?

 

[VenumX]

Now that I think about it...why would it even regenerate while braking when it can generate more power just by the engine itself.....?

 

[Dragonfly]

Yes, it appears as though then engine is generating more power than it requires for motion, and is using this to generate electricity for the battery. I suspect this is done because it has a target battery level it is aiming for. Maybe I should try doing the same with a full battery at some point.

It should always regen when braking, when the traffic ahead stops, or someone pulls into the gap, the ACC will use the brakes to slow the vehicle, I'm not saying it shouldn't brake, but should also use regen, more efficient braking, less wear on brake pads, and generates a small amount of power aswell.

 

[hermitdave]

I’ve only used Leaf30 and Outlander. Both regen while on cruise control. Outlander was better at it than Leaf30.

Leaf30 tends to use more power when in CC. With Outlander you could have B2 -normal to B5.

in both cases, the brakes are hybrid by design and regen is triggered irrespective of friction brakes

 

[Dragonfly]

in both cases, the brakes are hybrid by design and regen is triggered irrespective of friction brakes

That is the behaviour I would have expected.

 

[BarryH]

Yep, it's the way it's designed. I believe it is because it's ported over from an ICE car which doesn't of course have any Regen. It's possible that future models will have regen. However, the lake of regen will make very little difference to the overall efficiency I've found. The correct scenario for Adaptive Cruise Control (ACC) is on motorway/A Road cruising where there would be very little opportunity for regen in any case. The other scenario is where you are in traffic-jam traffic and for most people, this is only a small proportion of their drive time.

 

[Ian Morton]

Has anyone noticed that when you use ACC, you don't get any negative values on the power meter, I can't say for sure, but that implies that it is not using the KERS for regen. However going down a hill, or when someone pulls into the space, you can feel it pull back, but still no negative power reading.

I did feel it was slightly more efficient on the battery, than when I drove manually, but didn't generate as much power back, even when running in petrol mode.

Nope. It uses the brakes. Has always been the case unfortunately.

 

[Phil752]

Has anyone noticed that when you use ACC, you don't get any negative values on the power meter, I can't say for sure, but that implies that it is not using the KERS for regen. However going down a hill, or when someone pulls into the space, you can feel it pull back, but still no negative power reading.

I did feel it was slightly more efficient on the battery, than when I drove manually, but didn't generate as much power back, even when running in petrol mode.

didn't think there was any Regen, when in Active Cruise Control

 

[Deleted member 3150]

This is my personal interpretation- It’s the same on the ZS, regen and cruise don’t mix. The cruise control would be at constant odds with regen a bit like putting you foot on the break pedal. Think about it and it makes sense.

Also look at how the HS operates with 3 operating modes for battery management. Default, medium and high. You will see often the engine is on and idling in hybrid mode while the electric motor is doing the driving, as you move up the modes the engine is used more to recharge the battery. The design of a hybrid utilises mild regen compared to the ZS because regen and heavy petrol engines are at odds with each other. Coasting works better than rapid deceleration as a petrol engine has less torq and uses more fuel to recuperate velocity. The battery is also smaller on the hybrid and takes longer to recharge. I’m new to the HS but my Merc was the same, expect to lose your battery charge and never get it all back on a long journey, you can only save charge by using the higher recharge modes of medium and high. But these will burn more fuel however allowing more saved battery capacity for reaching urban areas. It’s a game of roulette getting that right. My mission is to end all hybrid journeys with zero battery.

 

[Dragonfly]

I can see your thinking working in a perfect world, however sometimes braking is needed, or can be better used. I have a regular 30mile drive I do, and 20ish miles are on dual carriageway. 2 situations where regen would help. 1 someone pulls into the gap, 2 downhill sections.

When I drive I get 2% more energy generated, than using the acc over the same dual carriageway section. While this is hardly going to save the planet, it does show the difference.

 

[hermitdave]

I can see your thinking working in a perfect world, however sometimes braking is needed, or can be better used. I have a regular 30mile drive I do, and 20ish miles are on dual carriageway. 2 situations where regen would help. 1 someone pulls into the gap, 2 downhill sections.

When I drive I get 2% more energy generated, than using the acc over the same dual carriageway section. While this is hardly going to save the planet, it does show the difference.

I, over time with Leaf 30 realised that Speed limit works better than Cruise Control. Leaf 30 has hybrid batteries braking and so did Outlander.

I believe this issue is a design issue - MG / SAIC are relatively new and over iterations they will adopt hybrid braking

 

[Dragonfly]

Yes I find the same in the leaf, but the HS has adaptive cruise control, which I prefer over the speed limiter.

 

[jem111111]

Is it me , or have others changed the way they drive slightly .
What I find I'm doing is using the regen to slow down as much as I can ( obviously using the brakes when I have to ) as its a good feeling that I'm slightly recharging the battery.
Obviously you have to be aware what's behind you as when the regen kicks in , it does not put the brake lights on , alerting drives behind you, you are slowing down.

 

[Dragonfly]

Yes read the road ahead, back off, and coast to the traffic light/slower car etc. I learnt this with the Leaf, and now do the same in the MG This is another reason, why a human can out regen the ACC even if it did use regen.