Pulse and Glide

[tom1l21]

Is there a reason that you can't glide past 41mph? If I'm on a main road that is either 35 mph or 40, I can't really pulse and glide without slowing everyone down. What are you thoughts on this? Am I doing something wrong?

[Frayadjacent]

The engine turns on above 42mph.

[bestmapman]

Hi Tom,

Above 41 MPH the ICE always is spinning so as not to overspeed MG1.

[bestmapman]

Here is a good introduction on how the HSD works. If after reading it, don't be scared to ask more questions.

[SageBrush]

It's the difference between gliding and coasting. Neither use fuel, but coasting has the additional energy consumption of free-spinning the engine. According to hobbit, this takes about 2 kW. When you consider that it only takes about 5 kW to move the car at ~ 40 mph on level ground, increasing energy use 40% to go one or two mph faster is painful -- at least to the mpg frugalista.

Wondering where the power is coming from, if not from burning fuel ? The car's momentum and/or battery charge.

[tom1l21]

Originally Posted by bestmapman

Here is a good introduction on how the HSD works. If after reading it, don't be scared to ask more questions.

Man that is a lot of data and a lot to understand for a noob like myself. Makes sense though that you can't glide over 41. How do most people P&G when the speed limit is 35mph? I seem to remember from a previous thread that the two optimal driving modes are "glide" (no arrows,99mpg) and "pulse" (orange arrows going into generator and wheels, and green arrows going into battery). I find that if I accelerate or "pulse", that I will get both arrows going into the generator and wheels from the engine, and arrows going from the generator into the wheels. But, if I take off of some of the acceleration, I'll again get just the arrows going from the engine to the wheels, and green arrows going into the battery. Is the latter acceleration better? I guess it is acceleration without the aid of the battery. Is this the correct acceleration to strive for?

[JimboK]

In a 35 MPH zone with a lot of impatient drivers who can't pass, P&G's usefulness is limited. My first priority is safety. Then I try to strike a balance between fuel economy and courtesy. If traffic is right on my rear at 35 MPH with no chance to pass, then I usually resign myself to going with the flow. If traffic is a little lighter, then I might glide down to the low 30s and pulse up to 40.

I also use terrain to my advantage when possible. Here in central VA we have gently rolling hills. Depending on the incline, I often can pulse up and glide down with little to no change in speed.

Part of my driving strategy also is seeking alternative routes that might be more favorable for P&G than the primary one -- lower speed limit, lighter traffic, more chances for traffic to pass, fewer red lights or stop signs, etc.

As for acceleration, I reiterate what I said in the other thread: Just aim to keep your iMPG above half your vehicle speed during ICE-on conditions and the arrows will take care of themselves, while the ICE is running within efficient ranges.

[andyprius]

Originally Posted by tom1l21

Is there a reason that you can't glide past 41mph? If I'm on a main road that is either 35 mph or 40, I can't really pulse and glide without slowing everyone down. What are you thoughts on this? Am I doing something wrong?

Altho the computer is limiting P&G at 41mph, one can get good mpg at higher speeds when the battery is blue to green, even when arrows show ICE on. Good mileage means anything above 50 mpg. Just change your P&G technique to 40-50mph or 50-60mph. Again it all depends on conditions and SOC of HV Bat.