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Future chevy volt range5/16/2023 ![]() It’s not clear to me how to game MM on this route. I’ll get a chance to test that this winter when I will have a 76 mile round trip with a 2000′ climb up to my turnaround point. According to Walter the window is more like 0.5- 1kwh. Bower : I remember during development we had a plot from GM that showed a bigger battery buffer zone or window than what GM ended up with. It's not clear to me how to game MM on this route. I'll get a chance to test that this winter when I will have a 76 mile round trip with a 2000' climb up to my turnaround point. As you can see from the plot SFC starts getting pretty bad above 3200 RPM or so. ie to switch out of MM on the steeper grades to avoid over reving the ICE. According to Walter the window is more like 0.5- 1kwh.Īs an alternative approach to mountain mode gaming I was thinking of using it as a shaving device. I remember during development we had a plot from GM that showed a bigger battery buffer zone or window than what GM ended up with. I seem to encounter many hills where the Volt uses the battery for half the small incline, but then the other half it needs to start revving the engine much higher.This seems to occur on many hills.If the window for charge/discharge were larger, this would be largely avoided and the end result MPG should be higher, I would think. Using this math model, I get a solution for condition 2 (above) which looks like this:Īs an aside, I think the Volt could be a lot more efficient if they increased the buffer during Charge Sustaining mode.That is, let it charge up more, and discharge more, so that the Volt can handle small hills (but larger than presently) without having to rev the engine higher mid-way through the small incline. This math model’s core is equations for road load, equations that describe the speed relationship and torque split of the planetary gear set, and also the engine map we have just discussed. Over the years I developed a simplified math model of the Volt. This operating mode has been observed by our own GM-Volt forum expert, saghost (Walter) using the Dashdaq data acquisition device. (Then after charging the battery to the top of its window shut the ICE off and run on the battery for a few miles.)Īs it turns out, the Volt chooses option 2. So what is the Volt to do? How should it be programmed to operate at this condition?ġ) Run in series mode and charge the battery with the ICE on its sweet spot, orĢ) Run with power split engaged AND charge the battery. Now notice what is happening at 50 mph: Bad SFC. Note that at 70-75 mph the road load is right on the sweet spot. To see some of these operating points, road loads (for a flat road) are overlaid on the map. The Volt doesn’t operate exclusively at this one sweet spot as many different power levels are required throughout its operating envelope. First, we see the engine’s “sweet spot” which occurs at 2,200 rpm.
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