Kers and ACC

[Dragonfly]

Given the discussion about the use of KERS when using Adaptive Cruise Control, can anybody confirm if MG4 uses KERS when using adaptive cruise control??

 

[Nerdy]

Also can anyone confirm if this is correct:

The salesman told me that the MG4 doesn't have any regenerative braking when using the brakes ie has traditional brakes, not blended brakes

 

[shaunuk]

It does regen in adaptive cruse, the numbers go negative as a percentage, seems to max out at -17%

 

[Dragonfly]

It does regen in adaptive cruse, the numbers go negative as a percentage, seems to max out at -17%

Thanks that's almost enough reason to change my order to an MG4 while waiting for the ZS

 

[t3rminalV]

Also can anyone confirm if this is correct:

The salesman told me that the MG4 doesn't have any regenerative braking when using the brakes ie has traditional brakes, not blended brakes

The power meter in ours definitely goes negative when using the brakes.

 

[DrAndyPerry]

It seems to be a setup like the model 3.... Come off the accelerator and you get full regen, brakes are then additional physical help but you don't get extra regen when brakes are applied.

This is unlike the Zoe where the first part of the regen is off the accelerator and the first part of the brake pedal is more regen, the brake calipers only but if you push harder on the brakes.

FWIW the tesla / MG4 way is my preferred way.

 

[t3rminalV]

It seems to be a setup like the model 3.... Come off the accelerator and you get full regen, brakes are then additional physical help but you don't get extra regen when brakes are applied.

This is unlike the Zoe where the first part of the regen is off the accelerator and the first part of the brake pedal is more regen, the brake calipers only but if you push harder on the brakes.

FWIW the tesla / MG4 way is my preferred way.

Im not sure to be honest. If I let off the accelerator completely in max regen, the power meter goes negative but if I then press the brakes, it goes much further negative than it does with no pedal inputs at all.

 

[siteguru]

That puzzles me - how can friction brakes increase regen? (Unless the brake switch coming on activates a regen+ mode?)

 

[t3rminalV]

Not sure to be honest, I'll be heading out for lunch in a little bit so will try and gather some data.

 

[DrAndyPerry]

That puzzles me - how can friction brakes increase regen? (Unless the brake switch coming on activates a regen+ mode?)

This is what happens in some other cars.

I've seen some momentary erratic numbers on the power meter at show speeds when touching the brakes but I don't think this was a regen+ model.

Interested in what other people think when they apply the brakes gently.

 

[t3rminalV]

Okay, just got back from the lunch run.

• I accelerated to 20mph (couldn't realistically get much faster due to where I was driving) and held there for a few seconds to get the power meter as close to zero as possible.
• I then ceased all pedal input on the accelerator and left the break alone - car was in regen level 3.
  • This resulted in the car slowing down on regen alone and the power meter showing -15 while slowing down.
• Accelerated to 20mph again as above.
• This time I let go of the accelerator until the power meter read -15 again and then started manually breaking with the pedal.
  • Doing this I was able to get the power meter down to about -25 but this seems to be where it maxed out regardless of how hard I was breaking.
• Repeated both of these tests three or four times each with essentially identical results.

 

[DrAndyPerry]

Ooh, interesting. I'll try this too.

 

[siteguru]

Page 189 of the manual says this:

IBS supports brake energy regeneration. When the brake
pedal is pressed for braking, the IBS will determine the
driver's demand for braking force. The drive motor will
convert the vehicle's kinetic energy into electrical energy,
which is stored in the high voltage battery when the vehicle
is decelerating. This process can improve the range of the
vehicle.

So it looks like @t3rminalV's observations are correct.

Note: page 186 talks about Regen.

 

[lfc958]

Science at its best , Book theory proven by practical experimentation