Engine braking when battery too full for Regen

[openair]

When the battery is too full to allow regen braking and the ice is used to engine brake is the behaviour of the brake pedal supposed to drastically charge? Have to push it significantly harder and some pulsing of the rate of deceleration behaviour with the pedal kept steady? Is the engine supposed to complete a warm up phase afterwards?

Edited November 2, 2016 at 04:26 PM by openair

[murphy]

The engine is not running in this mode.  No fuel is being fed to the cylinders.  It is being used as an air pump to provide back pressure to hold the car back.

[openair]

I didn't ask that. I understand that while it is actually engine braking it is not using fuel. However when the engine continued to turn after the vehicle came to a complete stop, only the white bar grew as i accelerated away from the stop and the instantaneous fuel guage and trip both showed fuel had been consumed it is definitely running.

 

Is the behaviour of the brake pedal supposed to be drastically different, having to push it much harder to get similar deceleration along with some pulsing in the rate of deceleration, during engine braking? Is the engine supposed to complete a warm up (20c, run for one minute) afterwards?

Edited November 2, 2016 at 06:26 PM by openair

[larryh]

The lCE will continue to run after engine braking until warmed up.  Regenerative braking no longer works.  It has to use the friction brakes so it will feel different.

[openair]

OK, thanks Larryh.

[rbort]

Agree with Larry, once the engine starts up, it will continue to run until it warms up.  You could pull over and power cycle the car to get rid of the engine.

 

If you had used the brake pedal only while the car's HVB was full, the engine would never start, the car is smart enough to stop doing regen and use the friction brakes.  I don't really feel anything different while braking, all you see is that the ^ arrow is gone from the battery even though you are braking.  That means the battery can't take any more regen.

 

If you shift to L to slow the car down, the engine will start up right away and it will burn fuel like you experienced, it will run and you're now on engine until it warms up.

 

Also if you use hill descent you can get the same effect.  If the battery is close to full, the safe bet is the brake pedal, that my friend won't start up the engine no matter what.

 

You can look at the battery charge level, while at 100% there are several options:

 

0.2/0.5 is the last option before 99% charge shows up.

0.1/0.4 the first number is 240v charge, the second is 120v.

0.1/0.3 same as above

0.1/0.2 same here, usually you see this when pulling away after charging is not 0.0/0.0.

 

If you are at 0.2/0.5, there is some room in the battery for L or hill decent.  Once you get close to 0.1/0.2 you're pretty much done.  You can use that as a knowledge factor for you of how charged the battery is between 99 and 100% indicated.

 

-=>Raja.

Edited November 4, 2016 at 11:53 PM by rbort